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This application claims the benefit of Korean patent application No. 1996-41342, filed Sep. 20, 1996, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of fabricating a multi-domain liquid crystal cell, and, more particularly, to a simplified method of fabricating the wide viewing angle liquid crystal cell.
2. Discussion of Related Art
A twisted nematic liquid crystal display (TN LCD) has a contrast angular problem, i.e., the transmittance in each gray level depends on the viewing angle. This contrast angular dependence is especially strong in the up and down directions, and is caused by the electrically induced liquid crystal (LC) director configuration.
To solve this angular dependence problem, a multi-domain LCD such as a two-domain TN LCD (TDTN LCD) and a domain-divided TN LCD (DDTN LCD) have been introduced. In the TDTN LCD, each pixel has two director configuration domains, where the two pretilted directions are in opposing directions. Applying a gray level voltage to this LCD, the LC directors in two domains are tilted in opposite directions. These configurations average the up and down directions transmittance. In the DDTN LCD, materials having different pretilt angles, such as organic or inorganic materials, are alternately aligned in the each pixel. The aligning process results in each aligned area (i.e., each domain) having a pretilt angle different from that of the neighboring domain.
In the multi-domain liquid crystal cell discussed above, the most useful aligning method is the so-called rubbing method. In the rubbing method, the alignment layer, which consists of polyimide-coated layers, is mechanically rubbed with a rubbing cloth, etc., so that microgrooves are created on the surface of the alignment layer. The periodic topology of mechanically grooved LCD-substrates minimizes the elastic deformation energy of liquid crystals by forcing the director to align parallel to the microgrooves. In the rubbing method, however, the defect of the microgrooves causes random phase distortion and light scattering, so that the image quality deteriorates. Further, the rubbing process generates dust and discharge on the alignment layer causing the damage to the substrate and resultant yield deterioration.
A new method called the photo-alignment method was recently introduced in order to overcome the substrate damage problem.
FIGS. 1A-1E are views showing the fabrication method of the dual-domain (or two domain) cell using the photo-alignment process. In the figure, the hatched region of the substrate indicates the region blocked by the opaque mask, and the arrow in the substrate indicates alignment direction. The arrow above the substrate indicates the irradiation direction of the light.
First, the first domain I of the photo alignment material-coated substrate is blocked by the opaque mask. Then the substrate is exposed to vertical linearly polarized light having a first polarization direction, in order to define the first degenerated alignment direction in the second domain II, as shown in FIG. 1A. Subsequently, as shown in FIG. 1B, the substrate is exposed to oblique linearly polarized light having a second polarization direction which is perpendicular to the first polarization direction in order to select one direction of the first degenerated direction. As a result, the first alignment direction is formed in the second domain II.
Thereafter, the first domain I is uncovered, and the second domain II is covered with the mask. The substrate is exposed to vertical linearly polarized light having a third polarization direction perpendicular to the first polarization direction to define the second degenerated alignment direction, as shown in FIG. 1C. At this time, the degenerated second alignment direction is perpendicular to the first alignment direction. Subsequently, the substrate is exposed to oblique light in order to select one degenerated direction, as shown in FIG. 1D. FIG. 1E is a view showing the dual domain cell where the alignment directions of the domains are fully determined, after removing the mask. As shown in FIG. 1E, the alignment directions in the first and second domains are perpendicular to each other.
This process is again carried out for a second substrate, and then the two substrates are combined to form a dual-domain liquid crystal cell.
The alignment process of a multi-domain cell, such as a dual domain cell, however, is complex and costly, since eight exposure processes and four masking processes are needed.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a method of fabricating a liquid crystal cell that substantially obviates one or more of the problems due to the limitations and disadvantages of the related art.
An object of the present invention is to provide a method of fabricating a wide viewing angle liquid crystal cell in which domains of the alignment layer absorb different amount of the energy during single exposure of the alignment layer to define a different alignment direction in each domain.
To achieve these an other advantages, and in accordance with the purpose of the present invention, as embodied and broadly described, the method of fabricating a liquid crystal cell includes the steps of:
(a) dividing a first substrate coated with a photo-alignment material into a plurality of domains;
(b) exposing the first substrate to a vertical light, whereby different domains of the first substrate absorb different amounts of energy; and
(c) exposing the first substrate to light at an oblique angle.
In another aspect of the present invention, there is provided a method of fabricating a multi-domain liquid crystal cell including the steps of:
(a) coating a substrate with a photo-alignment material;
(b) covering the substrate with a mask, the mask including a plurality of transparent mask sections, a plurality of partly transparent mask sections, and a plurality of opaque mask sections, the sections corresponding to a plurality of domains on the substrate;
(c) exposing the substrate to vertical light polarized in a first polarization direction so as to define degenerated alignment directions of domains of the substrate corresponding to the plurality of transparent mask section and the plurality of partly transparent mask sections,
(d) exposing the substrate to oblique light so as to select one alignment direction of the degenerated alignment directions;
(e) covering the substrate with another mask, such that the domains of the substrate having one alignment direction already selected are covered by opaque sections of the another mask, and remaining domains of the substrate not having one alignment direction already selected are covered either by transparent sections of the another mask or partly transparent sections of the another mask;
(f) exposing the substrate to vertical light polarized in a second polarization direction so as to define different degenerated alignment directions of the remaining domains; and
(g) exposing the substrate to oblique light so as to select one alignment direction of the different degenerated alignment directions.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
Additional features and advantages of the present invention will be set forth in the description which follows, and will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure and process particularly pointed out in the written description as well as in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention that together with the description serve to explain the principles of the invention.
In the drawings:
FIGS. 1A-1E are views showing the conventional fabricating method of the dual domain liquid crystal cell;
FIG. 2 is a graph showing the relation of the pretilt angle and the absorption energy or the alignment layer according to the present invention;
FIGS. 3A-3D are views showing the fabrication method of a two-domain LCD cell; and
FIGS. 4A-4F are views showing the fabrication method of a four-domain LCD cell.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
In the present invention, polysiloxane-based materials are used as an alignment layer, while polyvinylcinnamate is used as a conventional alignment material (see, e.g., the HASHIMOTO method disclosed in SID 95 DIGEST, p. 877). In the HASHIMOTO method, since the pretilt angle produced by the exposure is about 0.1-0.3 degree, which is very small, the desired pretilt cannot be obtained. In the present alignment materials, however, the pretilt angle depends upon the ultraviolet (UV) energy absorbed by the material, as shown in FIG. 2, so that the pretilt angle can be controlled appropriately.
FIGS. 3A-3D are views showing the first embodiment of the present invention using a mask having half-transparent mask section for fabricating liquid crystal call, specifically a DDTN liquid crystal cell. That is, the half-transparent mask 33 covers the first domain I of the alignment layer 32 on a substrate 31 to block it during exposure process, as shown in FIG. 3A. As a result, the first domain I absorbs only a part of the irradiated light, while the second domain II, which is not covered by a mask, absorbs the total irradiated light, such as, for example, ultraviolet light. This means that the first and second domains absorb different amounts of ultraviolet energy. The side of the pretilt angle depends upon the ultraviolet energy absorbed by the alignment layer, as shown in FIG. 2. With this exposure, the degenerated directions are formed in the first and second domains I and II.
Subsequently, when the alignment layer 32 is obliquely exposed to the ultraviolet light, a degenerated direction is selected, as shown in FIG. 3B. Thus, parallel alignment directions having different pretilt angles are formed in the first and second domains, as shown in FIG. 3C. FIG. 3D is a view showing the DDTN liquid crystal cell with the upper and lower substrates fabricated by the above photo-alignment process attached together.
In the structure of FIG. 3D, the alignment directions of each domain are parallel, but the pretilt angle is different for each domain. Accordingly, the domain having a large pretilt angle is facing the domain having a small pretilt angle, so that the viewing angle directions compensate each other for each domain and the two substrates.
FIGS. 4A-4F are views showing the second embodiment of the present invention. In this embodiment, the liquid crystal cell is a four-domain liquid crystal cell. In this figure, the angled line portion, the cross-hatched portion, and the clear portion indicate the half-transparent mask section 33b, the opaque mask section 33c, and transparent mask section 33a of the mask 33 respectively.
First, the substrate is covered by the mask 33. The first domain is covered by the half-transparent mask section 33b of the mask, the second domain II is covered by the transparent mask section 33a, the third and fourth domains III and IV are covered by the opaque mask section 33c, as shown in FIG. 4A. The transmittance of the half-transparent mask section 33b is about 30-80%. Subsequently, the substrate is vertically exposed to polarized light, such as ultraviolet light having a first polarization direction, in order to define the first degenerated alignment direction. As shown in FIG. 4B, the substrate is again exposed to oblique polarized light having a second polarization direction perpendicular to the first polarization direction, in order to define the first degenerated direction, which is approximately parallel to the exposure direction of the light. For this exposure, non-polarized light may be used. FIG. 4C shows the alignment direction of the first and second domains after the first exposure process. In the first and second domains, the alignment directions perpendicular to the first polarization direction are formed. However, since the third and fourth domains are covered by the opaque mask section 33c, no alignment direction is formed. The alignment directions of the first and second domain are parallel to each other, but the pretilt angles are different because of the difference in the absorption energy. In other words, the pretilt angle of the second domain is smaller than the pretilt angle of the first domain.
Thereafter, the first and second domains I and II, in which the alignment directions are already formed, are blocked with the opaque mask section 33c of the mask 33, the third and fourth domains III and IV are respectively covered by the half-transparent and transparent mask sections 33b and 33a. When the substrate is vertically exposed to polarized light having a third polarization direction parallel to the first polarization direction of the first exposure process, the second degenerated alignment directions perpendicular to the polarization direction are determined. Subsequently, the substrate is obliquely exposed to the polarized light having a fourth polarization direction in order to select one direction of the second degenerated directions, which is parallel to the exposure direction of the light. By the above second exposure process, the alignment directions are formed in the third and fourth domains III and IV, as shown in FIG. 4E. Like the alignment directions of the first and second domains I and II, the alignment directions of the third and fourth domains III and IV are parallel to each other but the pretilt angles are different. That is, the pretilt angle of the fourth domain IV is smaller than the pretilt angle of the third domain III because of difference of the UV energy absorbed by each domain.
FIG. 4F is a view showing the 4-domain liquid crystal cell of the present invention. As shown in this figure, the alignment directions of the first and second domains I and II having different pretilt angles are parallel to each other, and the directions of the third and fourth directions III and IV having different pretilt angles are also parallel to each other. Further, the alignment directions of the first and second domains I and II are perpendicular to the alignment directions of the third and fourth domains III and IV.
These alignment direction-determined substrates are then used as the upper and lower substrates, so that a 4-domain liquid crystal cell is assembled.
In the above process, the DDTN liquid crystal cell is fabricated with four exposure processes and two masking processes. Further, the 4-domain liquid crystal cell is fabricated with eight exposure processes and four masking processes. Thus, the wide viewing angle liquid crystal cell can be fabricated using a simplified process and at a lower cost.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | A method of fabricating multi-domain liquid crystal cell includes the steps of providing first and second substrates, the first and second substrates being coated with photo-alignment layer, covering the substrate with a mask which has a plurality regions having different transmittances, exposing the substrate to vertical light having a first polarization direction, and exposing the substrate to oblique light. The photo-alignment materials include polysiloxane-based materials. | 6 |
FIELD OF THE INVENTION
The present invention generally relates to object oriented computer programming and in particular to methods and systems of handling java class versioning.
BACKGROUND ART
During runtime, class files are loaded into a memory device when an instance of a class is created. In particular, a first class file can be loaded into the memory device. Thereafter, if another class file calls the first class file but expects that the first class file is an updated version but is actually not an updated version, a software exception error can undesirably occur.
Versioning techniques available today mostly rely on development best practices to ensure backward compatibility. When developing a new version of a Java class, it is up to the developer to maintain backward compatibility, to make sure that class signatures match, to check whether modification of existent code may impact other applications relying on the current class version.
Prior art solutions are known for handling java class versioning. U.S. Pat. No. 7,207,002 discloses techniques for serializing objects (such as Java objects), and deserializing those objects, in a manner that enables contents of the objects to be preserved following changes to definitions of the object structures. Objects are serialized. The serialized objects thereby capture class definition information for the class definition which was in effect when the object was serialized. Subsequently, if the class definition is changed, it is possible to deserialize the information from the markup language document to an object that uses the new class definition, without requiring access to a programming language specification of the now-obsolete class definition.
US20060218538 discloses a method for converting an object. In one embodiment, information is obtained from an object that identifies a first version of code associated with the object.
Using the obtained information, a minimized class and converter class are identified for converting the object from a first format associated with the first version of code to a second format associated with a second version of the code. The minimized class is utilized to read the object in the first format and the converter class is utilized to convert the read object into the second format. The use of such a converter handles cases where an object needs to be transferred between two software applications of different versions.
These solutions both refer to the serialization of Java objects, when these objects are transferred from one Java runtime to a different one, using a different version of the object class. However, these solutions do not allow for handling java class versioning at a same runtime.
SUMMARY
In order to address these and other problems, there is provided a method of handling a selected object class in an object-oriented environment during runtime, a computer program, a computer readable medium and a system. Additional embodiments are defined in the appended dependent claims.
Accordingly, the invention does not involve serialization. Indeed, according to the invention, an object is migrated inside the same runtime environment, when different versions of a class are coexisting because loaded through different libraries. Java classes version mismatch is now handled at runtime, while existing solutions refer to the serialization of Java objects (when these objects are transferred from one Java runtime to a different one, using a different versions of the object class).
With the invention, multiple versions of the same class can coexist inside a same Java Virtual Machine (JVM). A class can be associated to a version number. A minimal class version can be specified by client code at import level. According to the invention, the class loader is modified to check the called (or required or invoked or accessed) version (number) and load a new one if needed. Multiple versions of the same class may coexist because their internal name is extended with the version number. When creating a new object, the highest class version is used by default but the class definition pattern is extended by appending a version number to the name of the class in the form “:x”. This enables the coexistence of multiple class versions. It is another advantage of the invention to extend the Java import statement to specify the called (or required or invoked or accessed) class version, or a range of versions. According to certain embodiments of the invention, there is also enabled the loading of multiple versions of the same class at runtime. This avoids the dissemination of code in different class versions.
It is another advantage to migrate existing objects to a higher class version, on necessity and at runtime. Indeed, according to certain embodiments of the invention, an object is promoted or migrated from one class version to another class version at runtime. More specifically, a minimal class version is checked and an object is promoted or migrated from one class version to another class version if a higher class version is required. Further, pointers are provided by the older/basic object to previous version and next version of an object. The older object is kept accessible after the object migration. An object can thus be dynamically promoted at runtime. The Class version is checked at every object access or invocation. If the client code needs a higher version, a new object is created from the old one using the interface method promote ( ). It is thus an advantage of the invention to extend an old version of a class to enable upward compatibility between versions.
Another advantage of the invention is to leverage compiler validation mechanisms to ensure the considered and desired compatibility. Further, a java class compiler is provided with the features of validating the various versions of a java class and of extending the inheritance definition to support multiple versions with the same class name. The compiler is modified to embed in the generated byte code the actual version of a class to load. Multiple versions of the same class may then coexist because their internal name is extended with the version number. When creating a new object, the highest class version is used by default. It is another advantage of the invention to extend the inheritance definition to support class versions. This allows a class to explicitly extend a previous version of the same class. This further ensures backward compatibility of the multiple class versions and avoids code dissemination.
It is an advantage of the invention to detect differences between the old version and the new version. It is a further advantage to migrate an existing object to a higher version by adding only the missing parts (i.e. differences between the old version and the new version).
Further advantages of the invention will become clear to the skilled person upon examination of the drawings and detailed description. It is intended that any additional advantages be incorporated therein.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which like references denote similar elements, and in which:
FIG. 1 shows an exemplary java application comprising class files;
FIG. 2 is a flowchart illustrating a migration and promotion mechanism according to certain embodiments of the invention;
FIG. 3 illustrates the promotion of objects;
FIG. 4 illustrates an examplary promotion of objects;
FIG. 5 illustrates a java compiler which extends the definition of inheritance to support multiple versions with the same class name;
FIG. 6 illustrates the inheritance mechanism at compilation time and at runtime, in accordance with certain embodiments of the invention;
FIG. 7 illustrates a client view;
FIG. 8 shows coexistence of the different class versions;
FIG. 9 shows the migration step of the runtime Java object migration on class version upgrade.
DETAILED DESCRIPTION
The present invention provides a method and a system for handling class versioning in an object-oriented programming language.
The following description will be made with reference to Java environment, Java classes and Java class files, for illustrative purpose only. However, the skilled person will readily understand that the invention is also applicable to any equivalent language or object environment, including in particular any alternative to Java and any type of classes or class files.
To facilitate understanding of the detailed description of a certain preferred embodiments, there follow definitions of certain expressions used thereinafter:
Java is a programming language originally developed Sun Microsystems. Java applications are typically compiled to byte code that can run on any Java virtual machine (JVM) regardless of computer architecture (“write once, compile it once, and run it anywhere”).
A Java Virtual Machine (JVM) designates a set of computer software programs and data structures which use a virtual machine model for the execution of other computer programs and scripts. The model used by a JVM accepts a form of computer intermediate language commonly referred to as Java byte code. The JVM is a crucial component of the Java Platform. The JVM enables unique features such as Automated Exception Handling which provides ‘root-cause’ debugging information for every software error (exception) independent of the source code. The JVM is distributed along with a set of standard class libraries which implement the Java API (Application Programming Interface). The virtual machine and API have to be consistent with each other and are therefore bundled together as the Java Runtime Environment.
A Java byte code represents the form of instructions that the Java Virtual Machine executes. This language conceptually represents the instruction set of a stack-oriented, capability architecture.
Class libraries designate reusable code which is typically provided as a set of dynamically loadable libraries that applications can call at runtime. In computer science, a library is a collection of subroutines or classes used to develop software. Libraries contain code and data that provide services to independent programs. This allows code and data to be shared and changed in a modular fashion. Most libraries are not executables. Executables and libraries make references known as links to each other. Because the Java Platform is not dependent on any specific operating system, applications cannot rely on any of the pre-existing OS libraries. Instead, the Java Platform provides a comprehensive set of its own standard class libraries containing much of the same reusable functions commonly found in modern operating systems. The Java class libraries serve three purposes: they provide a set of functions to perform common tasks; they provide an abstract interface to tasks that would normally depend heavily on the hardware and operating system (for example network access tasks); when some underlying platform does not support all of the features a Java application expects, the class libraries work to gracefully handle the absent components, either by emulation to provide a substitute, or at least by providing a consistent way to check for the presence of a specific feature. Java libraries are the compiled byte codes of source code developed by the JRE implementor to support application development in Java. There are: core libraries, integration libraries, User Interface libraries, etc.
For purposes of understanding, the term “class” refers an object-oriented class. The term “class file” refers to an executable file or object instantiated from a class. The term “class name” refers to an identifier utilized to identify a class, such as a class “A” for example. The term “version number” refers to a version number associated with a class or class file. A class file can have a class file name formed utilizing a class name and a version number. For example, a class file named D — 00.01.02 belongs to a class “D” with a version number of 00.01.02.
For the sake of clarity and simplicity, when referring to the expression “version” the term “number” may be omitted (in particular when discussing about comparisons of versions). An “older” version conveys the meaning of “less recent”; it corresponds most of the time to a version number which is “inferior” than the one considered at present time. To the contrary, a version number which is “superior” (or greater than) indicates or conveys the meaning of “more recent”. It is observed that version numbering may correspond to an arbitrary choice since other naming conventions may be chosen. Consistency of the labeling only matters in this perspective. An assessment of the “age” (older/newer) or the “novelty” or the “up-to-date” characteristics of an object may be assessed by various means, such as hash comparisons or length of messages/contents/lines of codes (by way of example) or database of reference retrieval, etc.
Java is a trademark of Sun Microsystems. Other company, product or service names may be the trademarks or service marks of others.
FIG. 1 shows an exemplary java application comprising class files.
The Java application comprises a main class file 100 and additional class files 110 , 120 , 130 , 111 , 112 , 121 , 122 , 1111 , 1112 and 1301 .
A class file is a set of compiled files of associated routines within the Java source file 100 . As shown, the class file includes a class file 100 referred to as “main.class”, a class file 110 referred to as “A.class”, a class file 111 referred to as “D.class”, a class file 112 referred to as “E.class”, a class file 1111 referred to as “F.class”, a class file 1112 referred to “G.class”, a class file 120 referred to as “B.class”, a class file 121 referred to as “F.class”, a class file 122 referred to as “G.class,” a class file 130 referred to as “C.class”, and a class file 1301 referred to as “H.class”.
During operation, the Java application executes the class file main.class that utilizes the following class files: A.class, B.class and C.class. The class file A.class calls the class files D.class and E.class. The class file B.class calls the class files F.class and G.class. Further, the class file D.class calls the class files F.class and G.class. As shown, some class files may be used by different classes. For example, the class files F.class and G.class are utilized by both the D.class and B.class.
A first mechanism to handle java class versioning is to consider data indicating highest version of a class file.
More specifically, a called class file table is loaded with data indicating a highest version of a class file of the software application.
A first class version dependency file associated with a first class file is further retrieved. The first class version dependency file has both a first class name and a first version number associated with a second class file that is called by the first class file. A first record to the called class file table having both the first class name and the first version number associated with a second class file is then added.
A second class version dependency file associated with a third class file is further retrieved. The second class version dependency file has both a second class name and a second version number associated with a fourth class file called by the third class file. If the second class name is identical to the first class name in the called class file table and the second version number is higher than the first version number, then the first record in the called class file table with the second class name and the second version number associated with the fourth class file are updated.
FIG. 2 is a flowchart illustrating a migration and promotion mechanism according to certain embodiments of the invention.
At step 200 , the version of the class is specified. Then, at step 210 , the minimal class version is specified at class import declaration. Step 220 automatically takes, at object creation, the highest class version, and then, at step 230 , when accessing/invoking an object, its minimal class version is checked. A promote may be performed if needed.
The above mechanism enables a migration between versions. A specific Java interface “Promotable” containing a method “promote( )” is implemented to convert object from older class versions to the new one.
The Class loader may be modified. It checks if a called or required class level is available and loads it if needed.
The Object access or invocation is modified. When needed, there is converted existing objects from older class version to the new one through a call to the promote method. The basic class Object is extended to provide pointers on previousVersion and nextVersion of each object.
FIG. 3 illustrates the promotion of objects.
The interface <<Promotable>> allows migrating objects from a version to another as defined by the exemplary code below:
public interface Promotable
{
/** Promote an older object to this class version.
** This method initializes this object with the content
of an existing object of the same
** class but with a previous version.
** @param obj Object with older class version
*/
void promote (Object obj);
}
The above example defines an object promotion mechanism.
At runtime, every object access or invocation causes a check against the minimal called version. This checking step is generated or performed by the compiler, only when a particular class version is called (or required or invoked or accessed).
If there is a version mismatch, a new object is created on top of the old one to contain data added in the higher class version. Its interface method promote ( ) is called to perform the migration (following link “nextVersion”). The old object is still accessible by existing clients. Links “previousVersion” and “nextVersion” are updated in the new object to allow further version changes if needed. To keep or maintain compatibility, typical implementation still refers to “previousVersion” to access or invoke elements that are existing in it.
Class attributes should be accesses through getters/setters. If an object has been promoted, it is referred to the ancestor to set/get data that is available in both versions. The implementation of the promote method should sets the reference to the ancestor.
FIG. 4 illustrates an examplary promotion of objects, comprising an element 400 which is the initial version of a class Person, and an element 410 which represents a new version of this class (which implements a mechanism for promoting an existing object with older class version).
The element 420 provides an example of source code creating an instance named p 1 of the initial version of the class Person represented by element 421 . The object instance itself is represented by element 422 .
The element 430 is another piece of source code that explicitly references a newer version of the class person and where the instance created at step 420 (variable p 1 ) is referenced. This triggers the migration of the older object into a new one. A new instance is created, represented by 432 , which reference the newer version of the class represented by 431 . As this object has been promoted, the Java Virtual Machine automatically calls the method promote( ) in the new object 432 , passing as parameter the older version of the object. Links between old and new instance 445 are established, allowing both of them to coexist and to preserve existing references.
The element 440 is a piece of code which represents the creation of a new object instance directly using the new class version represented by element 431 . In this case, the object represented by element 442 is directly created with the class 431 , with no promotion mechanism invoked.
The method according to certain embodiments of the invention therefore allows for handling a selected object class in an object-oriented environment during runtime. Upon version mismatch (between expected and accessed object classes), an object class is generated from an older version version of the object class by invoking a promote interface method migrating object class from a version to another and extending the selected object class by updating pointer links to a previous version and to a next version of said object class. This enables to maintain backward compatibility and accessibility of multiple valid concurrent class versions. The older object class is maintained accessible after the object migration.
A same object can be exchanged or accessed by different programs, although the object has different versions. The older version of the object is an object of the same nature as other objects; the most recent object has got a link or pointer or another characteristics designating the older version.
All versions (past and present versions) are “maintained accessible”. This last expression conveys the meaning, in addition to its common sense, that the different versions are stored in memory and that they are able to be retrieved or reconstructed. The term “memory” primarily encompasses non-persistent memory means (RAM for example), but it also designates forms of persistent storage means (hard drive, flash memory, etc)
FIG. 5 illustrates a java compiler which extends the definition of inheritance to support multiple versions with the same class name.
The inheritance mechanism according to certain embodiments of the invention provides an extension of the class definition pattern. This mechanism further adds the possibility to append an optional version number to the name of the class in the form “:x”, which enables the coexistence of multiple class versions.
This inheritance mechanism further provides an extension of the inheritance definition to support class versions. This allows a class to “extend” a class with similar name with lower version number or no version at all. This enables the backward compatibility of the multiple class versions and avoids code dissemination. It also minimizes efforts on the developer side by leveraging compiler validation.
The inheritance mechanism according to certain embodiments of the invention also provides an extension of the import statement pattern to support versioning. It provides the developer with the ability to request a particular version of the class by specifying the number in the form “:x”. If no version number is supplied on the import statement, the highest version available on the build path is assumed.
According to the invention, the compiler is also enhanced to support the extensions described previously. Versioned classes are treated as individual classes and there is applied a traditional inheritance.
The element 500 is an example of source code where a new version of the class MyClass is defined by extending an older version. The distinction between the two versions of the same class is realized by appending an optional string “:<version_id>” at the end of the class name. If this version id is not given after the class name, the compiler takes by default the most recent version of the class, with the higher version number.
Element 510 focuses on the import directive that allows to optionally specifying a particular version of MyClass. If the version id is not given, the compiler uses the most recent version of the class.
Element 520 and 530 focus on the fact that both older and newer versions of the class are coexisting in the system. It is always possible to explicitly reference a particular version by appending the version id, and the inheritance mechanism assures the compatibility of newer version with older ones.
FIG. 6 illustrates the inheritance mechanism at compilation time and at runtime, in accordance with certain embodiments of the invention.
The element 600 represents the initial version of the class Person. The element 610 is an implementation of a first version “Person:1.1” implemented on top of Person. Element 620 represents an instance of this class “Person:1.1” as created in a Java runtime environment, containing all attributes and methods of Person and extensions of “Person:1.1.”.
Element 630 is a more recent version of Person, named “Person:1.2”, built by extending “Person:1.1”. Element 640 shows its representation in the Java runtime, including all attributes and methods from the initial class Person, and also extensions provided in “Person:1.1” and “Person:1.2”. But for the JVM and a compiler using this last version, this class “Person:1.2” can be accessed using only the atomic name Person.
FIG. 7 illustrates a client view.
The element 700 represents the last version of the class Person, named “Person:1.2” in the previous example, including all methods getPhone( ), getAddress( ), and getName( ). The figure shows how this class extends the class “Person:1.1” represented by the element 710 , itself extending the class Person represented by 720 .
On the client side, element 740 is an example of source code that only references the class Person. As the highest version available is the “version 1.2”, then all the features of this class (the three methods) are available to the client.
FIGS. 8 and 9 illustrate a further embodiment of optimizing the migration of existing object instances when a new version of a class is loaded. According to this embodiment, a particular way to define a new class version is provided which allows identifying only the differences between old and new class version. The JVM is modified to allow object migration only by adding these missing parts to existing objects that stay unchanged. This lead to a considerable saving of time and space spent in object migration.
FIG. 8 shows coexistence of the different class versions.
The figure shows the creation step of the runtime Java object migration on class version upgrade.
The element 801 is a first version of the class Person that has been loaded by the JVM. Element 800 represents an instance of this class, created either using explicit reference to the full class name including the version (Person:1), or created using the atomic class name “Person” but before loading a more recent version.
The element 811 is the source code of a newer class Person:2 extending the previous version “Person:1”. The element 810 represents an instance of this new class “Person:2”, that may be created using the atomic class name “Person” as “Person:2” is the most recent class version at that time.
A dynamic class upward migration is simplified by adding only class extension to existing objects. A class extending another one may add new attributes (extensions to memory footprint). Alternatively it may add or replace methods.
Defining a new version of a class by extending the previous one allows guaranteeing upward compatibility between versions. It also allows identifying what are the added elements of the objects.
Upgrading an existing object can be done by adding only new elements. A new separate memory block is allocated to handle added attributes (if any). Alternatively, new methods are invoked instead of old ones.
When a newer class version is loaded, it coexists with older version. Newly created object instances are created with the latest class version. Existing object instances may be migrated by adding only missing elements: for example, new attributes (extensions to memory footprint) or new (or replaced) methods. Existing objects are kept in memory as they are.
FIG. 9 shows the migration step of the runtime Java object migration on class version upgrade.
Element 901 is a first version of the class Person. The element 900 represents a first instance of the class Person created in the Java runtime.
After this creation, a new version “Person:2” of the class Person is loaded, represented by the element 911 . The element 910 represents a new instance of this new class Person, created with the same code than for element 900 , but which lead to a new memory representation that includes adds of “Person:2”.
The element 920 is an instance of the new class “Person:2” that is a migration of the existing instance of “Person:1” represented by 900 . Contrarily to the previous case represented by 910 , only the missing attributes are present in the object descriptor, plus a reference to the ancestor which allows getting values of existing fields directly in the older object. This allows also to maintain existing references to the previous object 900 but to make it viewable in a promoted way as a “Person:2”.
The invention can take form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc. In a high performance system, a hardware implementation of embodiments of the invention may prove advantageous for example.
Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. | There is disclosed a method of handling a given object class in an object-oriented environment, wherein it comprises, in response to the invocation of the given object class during runtime, the steps of: determining if the version associated with the given object class differs from a predefined minimal version and if so: (a) generating a new version of the object class from the previous version of the object class by invoking an interface method migrating an object class from a version to another; (b) extending the new object class by updating pointer links to the previous version of the given object class. The previous version of the object class may be maintained accessible after the object migration. | 6 |
FIELD OF THE INVENTION
The present invention relates to an accessory for a recreational board such as a snowboard or a surf board, for example.
BACKGROUND OF THE INVENTION
During the past few years great interest has arisen in the use of snowboards for healthful recreation. Concomitant with that interest, substantial strides have been made in the engineering and manufacturing of snowboards. As a result, high quality and lightweight snowboards have been developed and these devices are now quite popular. In turn, the costs of these devices has increased. A need has arisen to provide a method for securing these devices when unattended to discourage theft. The present invention meets this need in offering such a securing device.
Because of its light weight, compactness, and resistance to tampering and cutting, the cable, and especially the helically coiled cable, combined with a lock, is a desirable method of securing snowboards and the like to fixed structure. The present invention provides a bracket which allows the securing of the snowboard to a fixed object by use of a cable, or other means.
Heretofore, no suitable means were available for securing a snowboard to a fixed object while unattended. Prior art devices designed for skis are inadequate for securing snowboards due to dimensional differences between skis and snowboards.
U.S. Pat. No. 5,675,999 to Carlstrom presents one solution to this problem. Carlstrom provides a snowboard lock which comprises two opposing arms.
The present invention however, offers improvements to Carlstrom's device in that it is designed for greater compactibility and ease of carrying. The device of the present invention accomplishes this improvement by addition of a hinge in the securing arms thereby folding the arms. Another preferred embodiment of the present invention offers an accessory which provides a carrying strap for greater portability of the snowboard.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide a shackle accessory in the form of a bracket for attaching a securing means such as a cable, with or without a lock, to a snowboard.
It is another object of the present invention to provide such a bracket which is light weight and easy to use.
It is yet another object of the present invention to provide a bracket which folds into a convenient shape for carrying when not in use.
It is yet another object of the present invention to provide a bracket which provides ease of construction and design which lends itself to ease of attachment to and removal from the snowboard.
It is a still further object of the present invention to provide a bracket for a snowboard which also comprises a strap which can be used as a carrying handle.
It is a still further object of the present invention to provide a modified bracket for a snowboard which also comprises a cable to attach the snowboard to a fixed object which cable can also be used as a carrying strap or handle.
It is a still further object of the present invention to provide a modified bracket for a snowboard which also comprises a cable or strap to attach the snowboard to a fixed object which cable or strap can be adjustable in length to serve as a carrying strap for carrying the board over the shoulder or shortened to serve as a handle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the bracket of the present invention in use holding a snowboard in phantom.
FIG. 2 shows the bracket of the present invention when fully folded, for maximum compactability and ease of portability.
FIG. 3 shows the bracket of the present invention being unfolded from its configuration of FIG. 2 toward its configuration of FIG. 4.
FIG. 4 shows the bracket of the present invention being further unfolded from its configuration of FIG. 3 toward its configuration of FIG. 1.
FIGS. 5 and 6 show a modified bracket of the present invention which also comprises a strap which can be used for carrying the board by a handle or over the shoulder.
DETAILED DESCRIPTION
Turning more specifically to FIG. 1, a preferred embodiment of a bracket 2 of the present invention is shown in use. A snowboard is shown in phantom. The bracket 2 of the present invention is intended to fit around the snowboard between the bindings, near the center of the board. When in use, the bracket 2 is unfolded to create locking arms which fit around the snowboard. Hinge 12 is unfolded to create locking arm 8a, 8b (referred to as locking arm 8 when in this position)and hinge 14 is unfolded to create locking arm 4a, 4b (referred to as locking arm 4 when in this position). Locking arms 4,8 are of suitable length so that the width of the snowboard will fit inside the bracket. Hinges 12 and 14 are designed to open 180 degrees. Locking arms 4 and 8 are connected to spacer 22 at hinge 18 and hinge 16, respectively. The spacer is of suitable length to accommodate the thickness of the snowboard. Hinges 18 and 16 are designed to open 180 degrees also. Holes 6, 10 are situated near the end of each locking arm, which end is opposite to the end of each locking arm which is connected to spacer 22. Holes 6, 10 are situated so as to line up when the device is in the closed position. When holes 6,10 are lined up, they can receive locking means such a coiled cable, or the like, so as to secure the snowboard to a fixed object such as a ski rack or tree, for example.
Attention is drawn to FIGS. 2, 3, and 4 to illustrate the device of the present invention when not in use. FIG. 4 shows how the bracket folds to a compact shape which facilitates portability of the device. When fully folded, the bracket is dimensioned so as to fit inside a "fanny pack" or other small personal bag. Locking arms 4 and 8 are each folded at hinges 14 and 12 respectively. Locking arm 8a is folded toward locking arm 8b, and locking arm 4a is folded toward locking arm 4b. The locking arms thus folded are then folded toward each other at hinges 18 and 16. To employ the device from the folded position, simply unfold the locking arms away from each other as indicted by the arrows in FIG. 4.
FIG. 2 illustrates the device when fully folded. FIG. 3 shows the step of unfolding the folded locking arms 4, 8 away from each other. All surfaces which are in contact with the snowboard can be covered with a layer 20 of foam or other shock absorbent material which protects the surface of the board and also serves to hold the board in frictional contact with the bracket of the present invention.
In another embodiment of the present invention a carrying strap is provided which allows the user to carry the board over the shoulder. This embodiment is shown in use in FIG. 5. FIG. 6 illustrates the component parts of this embodiment when not in use.
The bracket of the present invention may be made of any suitable material including metal, plastic or wood. Suitable metals include aluminum or steel, for example. Suitable plastics include nylon, lexan, or other thermoplastic material. To protect the board from abrasion, all surfaces which are in contact with the board should be covered with shock-absorbent material such as foam. The entire bracket can also be dip-coated in plastic, if desired.
It has therefore been shown that the present invention provides a shackle accessory for securing a snowboard, with or without a lock to a fixed object. Furthermore, it has been shown that the bracket so provided is simple in construction and design and lends itself to ease of construction, simplicity of attachment to the snowboard, and is also simple and efficient to use.
It is clear that the present invention is well adapted to carry out the objects and to attains the ends and advantages mentioned herein as well as those inherent in the invention. While the invention has been particularly shown, described and illustrated in detail with reference to specific preferred embodiments and modifications thereof, it should be understood by those skilled in the art that the foregoing and other modifications are exemplary only, and that equivalent changes in form and detail may be made therein without departing from the true spirit and scope of the invention as claimed, except as precluded by the prior art. | A device for securing a snowboard is provided including a shackle accessory in the form of a bracket for attaching a securing mechanism, with or without a lock, to a snowboard. The bracket of the present invention collapses for ease of portability. Also provided is an alternate embodiment wherein the securing mechanism can be used as a carrying strap. | 8 |
FIELD OF THE INVENTION
The present invention generally relates to obstruction detection devices, and more specifically, to an obstruction detection device for use with a truss fabrication system.
BACKGROUND OF THE INVENTION
Truss fabrication systems typically include a truss assembly table and a gantry press. The truss assembly table includes several groups of planks forming the top of the table, and accessways or walkways spaced intermittently between the groups of planks providing operators access to portions of the table spaced from its edges. Operators place truss members and connector plates on the truss assembly table in predetermined configurations to form particular trusses. After the truss members and connector plates are placed on the table, the gantry press travels along the truss assembly table to press the connector plates into the truss members, joining them together. The gantry press typically includes a roller or hydraulic platen mounted on a gantry that engages the connector plates and presses them into the truss members. The gantry has wheels that run on rails or guides extending along the sides of the table or on the floor next to the table for guiding the gantry along the table.
Obstruction detection devices are mounted on the gantry press to detect whether obstructions are present on the table that may damage the press or be damaged by the press. For example, conventional obstruction detection devices for truss fabrication systems include push rods, light curtains, or light beams mounted on the gantry press above the table planks. If a push rod is contacted by an obstruction on the table, the push rods mechanically or electrically trigger a shut-off switch to stop the gantry press, preventing the obstruction from being contacted by the press. Similarly, if a light curtain or light beam is interrupted by an obstruction on the table, a shut-off switch is triggered to stop the gantry press and prevent the obstruction from being contacted by the press. However, if an obstruction is located beneath a level of the table planks, such as an operator bent over in a walkway extending between the planks of the table, the conventional push rods, light curtains, and light beams will not detect the obstruction. If an obstruction in a walkway rises to a level above the table planks after the push rods, light curtains, or light beams pass but before the roller passes, the roller may pinch the obstruction between the roller and truss members and/or connector plates positioned on the table planks, damaging the roller or the obstruction. Thus, there is a need for an obstruction detection device capable of detecting obstructions positioned in the walkways between the planks of the table.
SUMMARY OF THE INVENTION
In one aspect, an obstruction detection device for use with a truss fabrication system including a table having spaced accessways includes a support structure configured for movable attachment to a table having spaced accessways. An obstruction sensor is connected to the support structure and configured to detect obstructions in the spaced accessways of the table. The obstruction sensor has an activated state and a deactivated state. A control system is operatively connected to the obstruction sensor to activate and deactivate the obstruction sensor in response to a position of the obstruction sensor relative to the spaced accessways. The control system activates the obstruction sensor when the obstruction sensor is aligned with one of the spaced accessways of the table and deactivates the obstruction sensor when the obstruction sensor is out of alignment with the spaced accessways of the table.
In another aspect, a truss fabrication system includes a truss assembly table having a first side rail, a second side rail, and at least one accessway. A gantry press is movably mounted on the truss assembly table. A first obstruction detection device is mounted on the gantry press. A second obstruction detection device is mounted on the gantry press opposite the first obstruction detection device. Each of the first and second obstruction detection devices includes a support structure attached to the gantry press for movement with the gantry press along the truss assembly table. An obstruction sensor is connected to each support structure and configured to detect obstructions in the at least one accessway of the table. The obstruction sensor has an activated state and a deactivated state. A control system is operatively connected to each obstruction sensor for activating and deactivating the obstruction sensor in response to a position of the obstruction sensor relative to the at least one accessway. The control system activates the obstruction sensor when the obstruction sensor is aligned with the at least one accessway of the table and deactivates the obstruction sensor when the obstruction sensor is out of alignment with the at least one accessway of the table. A controller is configured to stop movement of the gantry press along the truss assembly table when an obstruction is detected in the at least one accessway of the table by the obstruction sensor.
In yet another aspect, a method of detecting obstructions in an accessway of a truss assembly table includes activating an obstruction sensor when the obstruction sensor moves into alignment with an accessway of a truss assembly table. The obstruction sensor is deactivated when the obstruction sensor moves out of alignment with the accessway of the truss assembly table.
Other objects and features will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective of a truss fabrication system having obstruction detection devices according to a first embodiment of the present invention;
FIG. 2 is a perspective of an obstruction detection device according to the first embodiment;
FIG. 3 is a fragmentary detail of FIG. 2 , showing an arm of the obstruction detection device;
FIG. 4 is a fragmentary detail of FIG. 1 , illustrating a first position of the obstruction detection device;
FIG. 5 is a fragmentary detail similar to FIG. 4 , illustrating a second position of the obstruction detection device;
FIG. 6 is a perspective of a truss fabrication system having obstruction detection devices according to a second embodiment of the present invention; and
FIG. 7 is a fragmentary detail of FIG. 6 , illustrating an obstruction detection device according to the second embodiment.
Corresponding reference characters indicate corresponding parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to drawings and more particularly to FIG. 1 , a truss fabrication system is indicated in its entirety by the reference number 20 . The system 20 generally includes a truss assembly table (generally designated by 22 ), a gantry press (generally designated by 24 ), and an obstruction detection device (generally designated by 26 ). The obstruction detection device 26 generally includes a frame 28 (broadly, a support structure), upper obstruction sensors 30 , lower obstruction sensors 32 , and control sensors 34 a , 34 b , as will be explained in further detail below.
As further illustrated by FIG. 1 , the truss assembly table 22 has a support 40 , supporting a plurality of parallel elongate planks 42 extending across the support, perpendicular to a direction of gantry press 24 travel. The planks 42 provide a substantially planar working surface for holding structural members (not shown) and connector plates (not shown) in a desired configuration. The structural members (e.g., stick lumber) and connector plates can be arranged in a desired configuration on the planks 42 to form a truss as generally known in the art. Track tubes or rails 44 extend along sides of the support 40 for guiding the gantry press 24 . The support 40 , planks 42 , and rails 44 are omitted at intervals along the table 22 to form accessways or walkways 50 in the table 22 . The accessways 50 allow operators access to locations on the table 22 remote from its edges for properly positioning structural members and connector plates.
The gantry press 24 moves relative to the truss table 22 . As mentioned previously, the truss table 22 includes rails 44 for guiding the press 24 as it moves along the table. The gantry press 24 has conventional drive wheels (not shown) for moving the press back and forth along the table 22 . The press 24 also includes a conventional roller or hydraulic platen (not shown) for pressing connector plates into the structural members to form trusses. The roller is rotatably mounted for rotation on the gantry press 24 and extends entirely across the table 22 . The drive wheels and roller are connected in a conventional manner to one or more motors (not shown). A controller 52 is operatively connected to the drive wheels and roller to control movement of the gantry press along the rails 44 and rotation of the roller. Because the features of the gantry press 24 described above are conventional, they will not be described in further detail. Those skilled in the art will appreciate that the gantry press 24 can have other configurations, such as being guided by floor rails, without departing from the scope of the present invention.
Referring to FIGS. 1-3 , the obstruction detection device 26 is mounted on the gantry press 24 so the device moves with the press along the rails 44 of the truss assembly table 22 . In the first illustrated embodiment, the truss fabrication system 20 has an obstruction detection device 26 mounted on opposite sides of the gantry press 24 . As mentioned previously, each obstruction detection device 26 includes a frame 28 , upper obstruction sensors 30 , lower obstruction sensors 32 , and control sensors 34 a , 34 b . The frame 28 includes a horizontal upper element 60 having a vertical arm 62 extending downward from each end. Although the frame 28 may be made of other materials without departing from the scope of the present invention, in one embodiment the frame is made of aluminum. In the illustrated embodiment, the frame 28 is mounted on top of the gantry press 24 , but the frame may be mounted on other portions of the gantry press without departing from the scope of the present invention.
Referring to FIG. 3 , the obstruction detection device 26 includes an upper obstruction sensor 30 positioned above the table 22 to detect obstructions above the table. The corresponding upper sensors 30 of each detection device 26 are aligned, forming a light curtain or detection plane extending entirely across the table 22 . When light passing between the sensors 30 is interrupted, the sensors send a signal to the controller 52 indicating an obstruction is present. The upper sensor 30 is positioned high enough above the planks 42 so structural members on the table 22 are not in the detection plane formed between the sensors. When an obstruction is detected, the upper sensor 30 sends a signal to the controller 52 to stop the motor system, thereby stopping the gantry press 24 traveling before the press contacts the obstruction. Although other sensors may be used without departing from the scope of the present invention, in one embodiment the upper sensor 30 is a model MLD520-T2L/MLD520-R2L sensor available from Leuze Electronic. In the illustrated embodiment, the arms 62 are pivotable relative to the upper element 60 so the upper sensors 30 move out of alignment with each other when either of the arms contacts an obstruction positioned immediately beside the table 22 so the gantry press 24 stops traveling. As will be appreciated by those skilled in the art, whenever the gantry press 24 is traveling, the leading pair of upper sensors 30 (relative to gantry press direction of travel) is operational to signal the controller 52 and stop the gantry press when the sensors senses obstructions to prevent damage to the obstruction or gantry press. In some embodiments, the trailing pair of upper sensors 30 is not energized to reduce power consumption. In other embodiments, the trailing pair of upper sensors 30 is energized but is ignored by the controller 52 . The direction of travel determines which sensors are active and which sensors are ignored. If an object is detected while the gantry is traveling, the gantry will stop and the electrical system will prevent the gantry from moving again in the first direction. The gantry will be permitted to travel in a second direction opposite from the first direction without the operator resetting the system until an obstruction is encountered in the second direction. Permitting travel in the second direction allows the operator to move the gantry away from a detected obstruction to clear the area. Once a direction has been disabled, the operator must perform a reset and acknowledge that the area has been cleared for the required travel direction. As will also be appreciated, dampers or gas springs 64 are mounted between the arms 62 and upper element 60 to prevent the arms from freely pivoting as the gantry press 24 moves.
As further illustrated in FIG. 3 , the obstruction detection device 26 includes a lower obstruction sensor 32 positioned below the planks 42 of the table 22 to detect obstructions in the accessways 50 of the truss assembly table 22 . The corresponding lower sensors 32 of each detection device 26 are aligned, forming a light curtain or detection plane extending entirely across the table 22 . Although other sensors may be used without departing from the scope of the present invention, in one embodiment the lower sensor 32 is a model MLD520-T1/MLD520-R1 sensor available from Leuze Electronic. As will be appreciated by those skilled in the art, obstructions below the table 22 are physically blocked from contacting the gantry press 24 by the planks 42 except in the accessways 50 where obstructions can rise as the gantry press 24 passes to contact the press without breaking the light curtain formed between the upper sensors 30 . To avoid sensing obstructions below the table 22 outside of the accessways 50 and unnecessarily stopping the gantry press 24 , the leading pair of lower sensors 32 is only operational to signal the controller 52 and stop the gantry press when those sensors are moving across the accessways. In some embodiments, the trailing pair of lower sensors 32 is not energized for sensing objects to reduce power consumption. In other embodiments, the trailing pair of lower sensors 32 is energized but is ignored by the controller 52 . In the latter case, the direction of travel determines which set of sensors are actively armed for detection, as described above in relation to the upper sensors 30 .
Referring still to FIG. 3 , two control sensors 34 a , 34 b mounted on brackets 70 extend from each arm 62 of the frame 28 . The control sensors identified as 34 a are spaced farther from the gantry press 24 than the control sensors identified as 34 b . The control sensors 34 a , 34 b are positioned on opposite sides of the lower sensor 32 . The corresponding control sensors 34 a , 34 b of each detection device 26 are aligned to detect a particular feature on the table 22 as will be explained below. Although other sensors may be used without departing from the scope of the present invention, in one embodiment each control sensor 34 a , 34 b is a model GM705S sensor available from IFM Efector, Inc. The leading and trailing control sensors 34 a , 34 b , respectively, associated with a particular pair of lower sensors 32 control when that pair of control sensors is operational to signal the controller 52 to stop the gantry press 24 . The control sensors 34 a , 34 b are operatively connected to the lower sensors 32 and are configured to detect when the lower sensor is aligned with an accessway 50 of the truss assembly table 22 . The control sensors 34 a , 34 b detect when the lower sensors 32 are aligned with an accessway 50 by detecting the presence of a target. In one embodiment, the target is a top surface of the side rail 44 of the truss table 22 , but the control sensors 34 a , 34 b can be configured to detect the presence of other targets without departing from the scope of the present invention.
As shown in FIG. 1 , the obstruction detection device 26 may include cover plates 72 mounted on the arms 62 to protect the sensors 30 , 32 , 34 a , 34 b from physically contacting obstructions to prevent the sensors from becoming misaligned.
Referring to FIGS. 4 and 5 , operation of the obstruction detection device will be described. As shown in FIG. 4 , when the leading control sensor 34 a detects the presence of the rail 44 , it sends a signal to deactivate or mute the lower sensor 32 to prevent the obstruction sensor from stopping the gantry press 24 when the frame 40 of the table 22 breaks the light curtain. Referring to FIG. 5 , when the trailing control sensor 34 b enters one of the spaced accessways 50 of the side rail 44 , it sends a signal to activate or unmute the lower sensor 32 so the lower sensor can then detect obstructions in the accessways 50 of the table 22 , and signal the controller 52 to stop the gantry press 24 if an obstruction is detected.
FIGS. 6 and 7 illustrate a second embodiment of an obstruction detection device 126 . The obstruction detection device 126 is similar to the obstruction detection device 26 described above, except for the differences pointed out below. In this embodiment, the obstruction detection device 126 includes upper obstruction sensors 130 , lower obstruction sensors 132 , and control sensors 134 a , 134 b mounted on collapsible bumpers 128 (broadly, support structures).
The obstruction detection device 126 is configured for use on the truss assembly table 22 , as described above in reference to the obstruction detection device 26 . The obstruction detection device 126 is mounted on the gantry press 24 so the device moves with the press along the rails 44 of the truss assembly table 22 . In the illustrated embodiment, the obstruction detection device 126 includes four collapsible bumpers 128 mounted on the gantry press 24 . Each collapsible bumper 128 includes a support 160 mounting the bumper to the gantry press 24 and a bumper flag 162 , as will be described in further detail below. Although the collapsible bumpers may be made of other materials without departing from the scope of the present invention, in one embodiment the bumpers are made of aluminum.
Referring still to FIGS. 6 and 7 , the obstruction device 126 , like the obstruction detection device 26 , includes an upper obstruction sensor 130 positioned above the table 22 to detect obstructions above the table. The corresponding upper sensors of opposed collapsible bumpers 128 are aligned, forming a light curtain or detection plane extending entirely across the table 22 . When light passing between the sensors 130 is obstructed, the sensors send a signal to the controller 52 indicating that an obstruction is present. The upper sensors 130 are positioned high enough above the planks 42 so structural members on the table 22 are not in the detection plane formed between the sensors. When an obstruction is detected, the upper sensors 130 send a signal to the controller 52 to stop the motor system, thereby stopping movement of the gantry press 24 before the press contacts the obstruction. Although other sensors may be used without departing from the scope of the present invention, in one embodiment the upper sensor 130 is a model PA46-2-500-Q2-NO1-PN sensor available from Omron Scientific Technologies, Inc.
In the illustrated embodiment, a scanner 168 is mounted on each side of the gantry press 24 at or near the center of the press. The scanners 168 can be used in addition to the upper sensors 130 , or in some cases can be used instead of the upper sensors. The scanners 168 scan at least about 180 degrees on each side of the gantry press 24 to detect obstructions. If an obstruction is detected, the scanners 168 send a signal to the controller 52 to stop the motor system, thereby stopping movement of the gantry press 24 before the press contacts the obstruction. Although other scanners may be used without departing from the scope of the present invention, in one embodiment each scanner 168 is a model 0532C-BP scanner available from Omron Scientific Technologies, Inc. It is understood that the scanners 168 could also be used with the obstruction detection device 26 in addition to or instead of the upper sensors 30 .
In the embodiment of FIGS. 6 and 7 , each bumper 128 is collapsible so the bumper flag 162 breaks the light curtain or detection plane of the upper sensors 130 when the bumper contacts an obstruction positioned immediately beside the table 22 so the gantry 24 stops moving. A gas spring 170 mounted to the support 160 permits movement of the bumper 128 relative to the gantry press 24 . The bumper flag 162 is positioned relative to the upper sensor 130 such that minimal movement of the flag towards the gantry 24 will break the light curtain of the upper sensors and signal the controller 52 to stop the gantry. As will be appreciated by those skilled in the art, whenever the gantry press 24 is moving, the leading (relative to the gantry press direction of travel) pair of upper sensors 130 is operational to signal the controller 52 to stop the gantry press when the sensors sense obstructions to prevent damage to the obstruction or gantry press. In some embodiments, the trailing pair of upper sensors 130 is not energized to reduce power consumption. In other embodiments, the trailing pair of upper sensors 130 is energized but is ignored by the controller 52 . The direction of travel from the controller 52 determines which sensors are actively looking for an obstruction and which sensors are ignored. If an object is detected while the gantry travels in a first direction, the gantry will stop and the electrical system will be disabled from traveling again in the first direction. The gantry will be permitted to move in a second direction opposite from the first direction without the operator resetting the system until an obstruction is encountered in the second direction. Permitting the gantry to move in the second direction allows the operator to move the gantry away from a detected obstruction to clear the area. Once a direction has been disabled, the operator must perform a reset to acknowledge the area has been cleared for the required travel direction.
As further illustrated in FIG. 7 , the obstruction detection device 126 includes a lower obstruction sensor 132 positioned below the planks 42 of the table 22 to detect obstructions in the accessways 50 of the truss assembly table 22 . The lower obstruction sensor 132 of the obstruction detection device 126 works as described above with reference to the lower obstruction sensor 32 of the obstruction detection device 26 . The corresponding lower sensors 132 on each bumper 128 are aligned, forming a light curtain or detection plane extending entirely across the table 22 . If the collapsible bumper 128 contacts an obstruction and collapses, the corresponding lower sensor 132 moves out of alignment with the other sensor, breaking the light curtain extending between the lower sensors. The light curtain between the lower sensors 132 is also broken by an obstruction positioned between the sensors. Although other sensors may be used without departing from the scope of the present invention, in one embodiment the lower sensor is a model MLD520-T1/MLD520-R1 sensor available from Leuze Electronic. As will be appreciated by those skilled in the art, obstructions below the table 22 are physically blocked from contacting the gantry press 24 by the planks 42 except in the accessways 50 where the obstructions can rise as the gantry press passes to come in contact with the press without breaking the light curtain formed between the upper sensors 130 . To avoid sensing obstructions below the table 22 outside of the accessways 50 and unnecessarily stopping the gantry press 24 , the leading pair of lower sensors 132 is only operational to signal the controller 52 and stop the gantry press when those sensors are moving across the accessways. In some embodiments, the trailing pair of lower sensors 132 is not energized for sensing objects to reduce power consumption. In other embodiments, the trailing pair of lower sensors 132 is energized but is ignored by the controller 52 . In the latter case, the direction of travel determines which set of sensors are actively armed for detection, as described above in relation to the upper sensors 130 .
Referring still to FIGS. 6 and 7 , two control sensors 134 a , 134 b are mounted on each bumper 128 . The control sensors 134 a , 134 b can be mounted on a bracket (not shown) mounted to a front plate 172 of the bumper 128 , to the support 160 , on the front plate of the bumper, or any combination thereof. The control sensor 134 a is spaced farther from the gantry press 24 than the control sensor 134 b . The control sensors 134 a , 134 b are positioned on opposite sides of the lower sensor 132 . The corresponding control sensors 134 a , 134 b of opposing bumpers 128 are aligned to detect a particular feature on the table 22 . Although other sensors may be used without departing from the scope of the present invention, in one embodiment each control sensor 134 a , 134 b is a model GM705S sensor available from IFM Efector, Inc. The leading and trailing control sensors, 134 a , 134 b , respectively, associated with a particular pair of lower sensors 132 control when that pair of control sensors is operational to signal the controller 52 to stop the gantry press 24 . The control sensors 134 a , 134 b are operatively connected to the lower sensors 132 and are configured to detect when the lower sensor is aligned with an accessway 50 of the truss assembly table 22 . The control sensors 134 a , 134 b detect when the lower sensors 132 are aligned with an accessway 50 by detecting the presence of a target. In one embodiment, the target is a top surface of the side rail 44 of the truss table 22 , but the control sensors 134 a , 134 b can be configured to detect the presence of other targets without departing from the scope of the present invention
As illustrated, the front plates 172 of each bumper 128 protect the sensors 132 , 134 a , 134 b from physically contacting obstructions to prevent the sensors from becoming misaligned or physically damaged. A cover plate 174 can also be included to protect the upper sensors 130 from physically contacting obstructions.
The operation of the obstruction detection device 126 is similar to the operation of the obstruction detection device 26 described above. When the leading control sensor 134 a detects the presence of the rail 44 , it sends a signal to deactivate or mute the lower sensor 132 to prevent the obstruction sensor from stopping the gantry press 24 when the frame 40 of the table 22 breaks the light curtain. When the trailing control sensor 134 b enters one of the spaced accessways 50 of the side rail 44 , it sends a signal to activate or unmute the lower sensor 132 so the lower sensor can then detect obstructions in the accessways 50 of the table 22 , and signal the controller 52 to stop the gantry press 24 if an obstruction is detected.
Having described the invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims.
When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above products and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | An obstruction detection device for use with a truss fabrication system including a table having spaced accessways. The obstruction detection device includes a support structure configured for movable attachment to a table having spaced accessways. An obstruction sensor is connected to the support structure and configured to detect obstructions in the spaced accessways of the table. The obstruction sensor has an activated state and a deactivated state. A control system is operatively connected to the obstruction sensor to activate and deactivate the obstruction sensor in response to a position of the obstruction sensor relative to the spaced accessways. The control system activates the obstruction sensor when the obstruction sensor is aligned with one of the spaced accessways of the table and deactivates the obstruction sensor when the obstruction sensor is out of alignment with the spaced accessways of the table. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a thin film transistor-array (TFT-array) to be used in the liquid crystal display in, for example, active matrix type liquid crystal display and method of manufacturing the same, and a liquid crystal display provided with the same.
The conventional active matrix type liquid crystal display adopts a twisted nematic system for grasping the liquid crystal between two opposite transparent insulating substrates, each of the substrates having a transparent electrode being formed on the surface, and for applying the electric field to the liquid crystal in a direction vertical to the substrate to drive the liquid crystal for effecting the display.
FIG. 11 shows the sectional view of the liquid crystal panel of the active matrix type liquid crystal display adopting the conventional twisted nematic system. Referring to the drawing, reference numeral la is a transparent insulating substrate such as glass substrate or the like, reference numeral 2 is a gate electrode provided with gate line formed on the transparent insulating substrate 1a, reference numeral 5 is a gate insulating film, reference numeral 6 is an amorphous silicon formed on the gate electrode 2 through the gate insulating film 5, reference numeral 7 is an amorphous silicon, with impurities such as phosphorus or the like doped into it, formed on the amorphous silicon 6, reference numerals 9 and 10 are a source line and a drain electrode, with a source electrode for composing the semiconductor element together with the amorphous silicon 6, formed on the amorphous silicon 7 with impurities being doped into it, reference numeral 11 is a passivation film composed of transparent insulating film such as silicon nitride, silicon oxide or the like, reference numeral 26 is a pixel electrode electively connected with the drain electrode, reference numeral 19 is an alignment film. A TFT substrate 20 is composed of the above described elements. Also, reference numeral 23 is an opposite substrate with a black matrix 21, an overcoat layer 22 and an counter electrode 27 formed on the transparent insulating substrate 1a. Reference numeral 24 is a liquid crystal, and reference numeral 25 is a light polarizing plate. In the liquid display adopting the twisted nematic system, the electric field, vertical in direction to the transparent insulating substrate la face, is applied to the liquid crystal 24 grasped between the TFT substrate 20 and the opposite substrate 23.
But the liquid crystal display adopting the twisted nematic system has problems on the displaying in that the contrast is considerably lowered when the visual angle direction has been changed, and the gradation level has been inverted when the multi-gradation has been displayed.
In the liquid crystal displaying apparatus of active matrix type, a system of making the direction of the electric field to be applied to the liquid crystal parallel in direction to the substrate face. For example, Asia Display '95, pp. 577 to 580 by Mr. Ohta and others show that the contrast is hardly lowered when the visual angle direction has been varied, and the gradation level has been hardly inverted when the multi-gradation display has been effected in accordance with the system adopted.
A method of forming two electrodes with two types of layers of the source drain line layer and the gate electrode layer, shown by Asia Display '95, pp. 707 to 710 by Mr. Ohta and others, and a method of forming two electrodes together with the use of the source drain wiring layer, disclosed in Japanese Unexamined Patent Publication No. 128683/1995, are proposed as the method of forming two electrodes to be formed on the thin film transistor integrating apparatus for applying the electric field to the liquid crystal in a direction parallel to the substrate face.
A system for applying the electric field upon the liquid crystal in a direction parallel to the substrate face requires the electric field strong for driving the liquid crystal. When the voltage of, for example, 5 V is applied on the electrode, the electric field strong enough to drive the liquid crystal fully is obtained only when the electrode spacing is made approximately 4 μm through 6 μm. Also, when dispersion is caused in the space between the electrode for forming the electric field, dispersion is caused in the brightness on the display of the liquid crystal display by changing in the strength of the electric field to cause the uneven display, and further the variation amount of the strength of the electric field to the change amount of the electrode spacing becomes larger as the electrode spacing becomes narrower, thus increasing the dispersion in the brightness on the display.
Some methods are not effective which have been conventionally proposed as a method of forming two electrodes for forming the electrode field in a direction parallel to the substrate face. For example, a method of forming two electrodes with different layers had problems in that it was difficult to form with good precision the electrode interval of few micro meters level because of the alignment error between the layers, or the boundary of the divided exposure portion was visually recognized, because the shift amount of alignment error between the layers was different for each divided region in the formation of the liquid crystal display panel by the divided exposure.
Also, in a method of forming with the source drain line layer together with two electrodes, there is required thickness sufficient enough to cover the difference between the layers, because the source drain line was formed on the uneven face due to the gate electrode or the like formed in the lower layer although a problem to be caused due to shift of the alignment error between the layers was not caused. Thus, it was difficult to form with precise the electrode interval of few micro meters level, because the thickness of the two electrodes to be formed at the same time became thicker and the patterning of the high precision was hard to effect. Also, a problem in that the panel aperture ratio for determining the brightness of the display of the liquid crystal displaying apparatus was not obtained was caused because it was difficult to form the width of the electrode narrower.
Accordingly, an object of the present invention is to provide a TFT-array which is equal within the substrate in the strength of the electric field in a direction parallel to the substrate face and is small in the area of the line and the electrode portion by formation of the electrode with high precision for forming electric field in the direction parallel to the substrate face.
Also, another object of the present invention to provide a liquid crystal display which is hardly lowered in contrast when the visual angle direction has been changed and is hardly inverted in the gradation level in the multi-gradation displaying, and is even in display and higher in aperture ratio by adoption of a system for making the direction of the electric field to be applied upon the liquid crystal parallel to the substrate face by the mounting of the TFT-array which is equal within the substrate in the strength of the electric field in a direction parallel to the substrate face, and is small in wiring and the electrode portion.
SUMMARY OF THE INVENTION
The TFT-array of the present invention comprises a substrate, a gate electrode, a first and second electrode provided on the substrate simultaneously with the gate electrode, an insulating film formed on the gate electrode, the first and the second electrode, a semiconductor layer formed on the gate electrode in such a manner that the insulating film is interposed between the semiconductor layer and the gate electrode, a pair of electrodes, either of which is connected with the first electrode or the second electrode, said pair of electrodes defining a semiconductor element together with the semiconductor layer.
It is preferable that the first electrode and the second electrode are arranged so that they are comb-shaped respectively and are opposed to each other.
Also, a common line for forming a storage capacitance is formed on the gate electrode side, and another common line for applying the voltage upon the first electrode or the second electrode is formed on the opposite side with the regions forming the electric field in a direction parallel to the substrate being grasped.
It is preferable that the common line for forming the storage capacitance and another common line for applying the voltage upon the first electrode or the second electrode is electrically connected to at least one first electrode or second electrode.
It is preferable that the low resisting material is connected with at least either of the line for applying the voltage upon the gate electrode, the first electrode or the second electrode or the common line for forming the storage capacitance.
It is preferable that all the insulating film or part of it is removed which is formed on the region for forming the electric field in the direction parallel to the substrate face.
In accordance with the present invention, there is also provided a method of manufacturing a TFT-array including steps of:
simultaneously forming the gate electrode, the first electrode and the second electrode, with the same material, on the substrate,
forming the gate insulating film on the gate electrode, the first electrode and the second electrode,
forming a semiconductor layer through the insulating film on the gate electrode, and
forming a pair of electrodes for composing semiconductor element together with the semiconductor layer.
Also, the common line for forming a storage capacitance is formed simultaneously with the same material as those of the gate electrode, the first electrode and the second electrode.
Also, a step is included of coating the low resisting member on at least either of the wiring for applying the voltage upon the gate electrode, the first electrode or second electrode, and the line for forming the storage capacitance.
Also, the liquid crystal display of the present invention is provided with a transparent insulating substrate, a TFT-array of the above construction formed on the transparent insulating substrate, an opposite substrate for grasping the liquid crystal material together with the transparent insulating substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view showing one pixel element of the TFT-array of the invention;
FIG. 2(A) to 2(E) are each sectional view showing the manufacturing step of portions taken along a line of A--A of FIG. 1;
FIG. 3 is a plan view of one pixel element portion of the TFT-array showing one embodiment of the invention;
FIG. 4 is a plan view of one pixel element portion of the TFT-array showing another embodiment of the invention;
FIG. 5 is a plan view of one pixel element portion of the TFT-array showing still another embodiment of the invention;
FIG. 6 is a plan view of one pixel element portion of the TFT-array showing yet another embodiment of the invention;
FIGS. 7(A) to 7(F) are each sectional view showing the step of manufacturing the portion along a line of B--B of FIG. 6;
FIG. 8 is a plan view of one pixel element of the TFT-array showing one embodiment of the invention;
FIGS. 9(A) to 9(C) are each sectional view of a portion taken along a line of C--C of FIG. 8;
FIG. 10 is a sectional view showing the liquid crystal panel of the liquid crystal display of the invention; and
FIG. 11 is a sectional view of the liquid crystal panel of the conventional liquid crystal display.
DETAILED DESCRIPTION
Embodiment 1
TFT-array in one embodiment of the present invention, and a liquid crystal display with the same mounted on it will be described hereinafter. FIG. 1 is a plan view showing one pixel element of the TFT-array of the present invention. FIG. 2 is a sectional view showing the manufacturing step of portions taken along a line of A--A of FIG. 1. Referring to the drawings, reference numeral 1 is a substrate. Reference numeral 2 is a gate electrode provided with gate line formed on the substrate 1. Reference numerals 3 and 4 are a pixel electrode and an counter electrode for forming the electric field in a direction parallel to the substrate 1 face, formed simultaneously with the gate electrode 2, on the substrate 1, each having comb-shaped, and being arranged to oppose each face. Reference numeral 5 is a gate insulating film formed on the entire face on the gate electrode 2, the pixel electrode 3 and the opposite electrode 4. Reference numeral 6 is an amorphous silicon formed on the gate electrode 2 through the gate insulating film 5. Reference numeral 7 is an amorphous silicon, with impurities such as phosphorus or the like doped into it, formed on the amorphous silicon 6. Reference numeral 8 is a contact hole formed in the gate insulating film 5 on the drain side electrode 3. Reference numerals 9 and 10 are the source line and drain electrode formed on the amorphous silicon with impurities doped into it with the drain electrode 10 being electrically connected with the pixel electrode 3 formed through the contact hole 8.
Reference numeral 11 is a passivation film composed of transparent insulating film such as silicon nitride, silicon oxide or the like. Reference numeral 12 is common line for applying the voltage upon the opposite electrode 4, which is formed on the side opposite to the gate electrode 2 with the region where the electric field is formed being grasped. Also, the storage capacitance for retaining the voltage by the pixel electrode 3 and the counter electrode 4 is formed by the superposition between the end portion of the electrode on both the ends within one picture element of the opposite electrode 4 having the comb-shape and the drain electrode 10. The TFT-array is formed so that the picture elements composed of the above described elements are arranged in matrix shape.
The method of manufacturing the TFT-array in the present embodiment will be described hereinafter. At first, as shown in FIG. 2(A), the gate electrode 2, and the pixel electrode 3 and the counter electrode 4 for forming the electric field in a direction parallel to the substrate 1 face are formed, on the substrate 1, of film as thick as approximately 0.03 μm through 0.6 μm with the use of either of the single layer film composed of either of Cr, Al, Mo, Ta, Cu, Ti, W, Al--Cu, or alloy among them, or transparent conductive material such as ITO or the like, or multi-layer film laminated with them. An etching method wherein the patterns section becomes rectangular may be also used although the taper etching method where the pattern section becomes trapezoidal was used as an etching method of pattern-forming at the same time the gate electrode 2, the pixel electrode 3, and the counter electrode 4.
As shown in FIG. 2(B), the gate insulting film 5, the amorphous silicon 6 and the amorphous silicon 7 with impurities being doped into it are deposited successively, and the amorphous silicon 6 and the amorphous silicon 7 with impurities doped being into it are etched at the same time with the use of the etching resist formed by the photo-lithography so as to form in the position above the gate electrode 2 the pattern of the amorphous silicon 6 and the amorphous silicon 7 with impurities being doped into it. The gate insulating film 5 is formed with the use of either of the silicon nitride and silicon oxide, film oxide of the gate electrode 2 material, or multi-layer film laminated with them. Also, micro-crystal silicon or the like with impurities such as phosphorus being doped into it may be also used, instead of amorphous silicon 7 with impurities being doped into it.
As shown in FIG. 2(C), a contact hole 8 is formed in the gate insulating film 5 on the pixel electrode 3. Then, the either of the single layer film composed of either of Cr, Al, Mo, Ta, Cu, Ti, W, Al--Cu, Al--Si--Cu or alloy among them, or transparent conductive material such as ITO or the like, or the either of multi-layer film laminated with them is filmed as shown in FIG. 2(D) so as to form the source line 9 and the drain electrode 10, by the patterning, which are divided into two in such a manner as to be spaced with each other on the pattern of the amorphous silicon 7 with impurities being doped into it. At this time, the drain electrode 10 is electrically connected with the pixel electrode 3 through the contact hole 8. Thereafter, the amorphous silicon 7 with impurities being doped into it is removed in etching with the portion covered by the source wiring 9 and the drain electrode 10 remaining. Finally, transparent insulating film such as silicon nitride or silicon oxide or the like is formed on the entire face as the passivation film 11 as shown in FIG. 2 (E). By the above described steps, the TFT-array can be formed which has the pixel electrode 3 and the counter electrode 4, on he substrate 1, for causing the electric field in the direction parallel to the substrate 1 face.
A TFT-array may be also formed in connection with the method of forming the channel-passivation tin film transistor, with the passivation film (channel passivation film) of silicon nitride or the like on the amorphous silicon 6 (channel portion) being interposed, instead of the channel-etched thin film transistor, although the present embodiment shows a case where the method of forming the thin film transistor integrating apparatus for forming the electrode for forming the electric field in the direction parallel to the substrate 1 face simultaneously with the gate electrode 2 is combined with the method of forming the channel etching type thin film transistor.
According to the present invention, a TFT-array can be formed, which is equal within the substrate 1 in the strength of the electric field in a direction parallel to the substrate 1 face and is small in the area of the electrode portion of the electric field forming region. This is because the precision of the interval value between the electrodes is not reduced due to the shift between the uneven lower layer and the superposition between the layers, because the pixel electrode and the counter electrode 4 for forming the electric field in the direction parallel to the substrate 1 face are formed simultaneously on the substrate 1 or finer formation can be made with the thinner film of the pixel electrode 3 and the counter electrode 4, because the electrodes are formed on the flat substrate 1.
Embodiment 2
FIG. 3 is a plan view of one pixel element portion of the TFT-array showing Embodiment 2 of the present invention. Referring to the drawing, reference numeral 13 is an electric field voltage formed by the pixel electrode 3 and the counter electrode 4, common line for forming the storage capacitance for retaining the voltage to be applied upon the liquid crystal in the liquid crystal display, which are formed on the substrate 1 simultaneously with the gate electrode 2. The same parts as those in FIG. 1 are designated with the same reference numerals in FIG. 3 with no description of the same parts being given. Also, as the method of manufacturing the TFT-array in the present embodiment is the same as in Embodiment 1, the description thereof will be omitted.
In Embodiment 1, the pattern of the end portion of the counter electrode 4 was necessary to be made larger due to increase the storage capacitance, because the storage capacitance was formed by the superposition between the end portion of the counter electrode 4 and the drain electrode 10. Or the counter electrode 4 could not make the line width narrower, because the load to be applied upon the line 12 for applying the voltage upon the counter electrode 4 was large due to the formation of the storage capacitance in the counter electrode 4.
The present embodiment allows the pixel electrode 3, the drain electrode 10 of a portion connected with the thin film transistor portion to be superposed through the contact hole 8 on the common line 13 and sufficient storage capacitance to be easily formed by the formation of the common line 13 for forming the storage capacitance on the side same as that of the gate electrode 2 with respect to the region where the electric field is formed and between the gate electrode 2 and the pixel electrode 3. Also, in the counter electrode 4, the load to be applied upon the line 12 for applying the voltage upon the counter electrode 4 becomes small because of no storage capacitance formed. The width of the line 12 can be made narrower. In the liquid crystal display, the aperture ratio for determining the brightness of the display can be increased. In the present embodiment, sufficient storage capacitance can be easily obtained.
Embodiment 3
Although the common line 13 for forming the storage capacitance is provided independently in Embodiment 2, the line defect is not caused because of the connection with the counter electrode 4 by the electric connection of the common line 13 with one line shaped electrode within the counter electrode 4 having the comb-shape even when either of the common line 13 or line 12 for applying the voltage upon the counter electrode 4 is disconnected. The counter electrode 4 to be connected with the common line 13 may be plural.
Also, as shown in FIG. 5, the line 12 for applying the voltage upon the counter electrode 4 is not necessary to be connected with the line 12 of the adjacent pixel element with the electric connection of the common line 13 with at least one line shaped electrode within the counter electrode 4 having the comb shape.
According to the present embodiment, the crossing portion between the line 12 and the source line 9 can be reduced and the disconnection and the short between layers due to the difference of the lower layer, thereby improving the yield, because the diffuse property of the line is increased due to the connection between the common line 13 and the line 12 for applying the voltage upon the counter electrode 4 or the line 12 for applying the voltage upon the counter electrode 4 is not connected with the line 12 of the adjacent pixel element.
Embodiment 4
FIG. 6 is a plan view of one pixel element portion of the TFT-array showing Embodiment 4 of the present invention. FIG. 7 is a sectional view showing the step of manufacturing the portion along a line of B--B of FIG. 6. In the drawing, reference numeral 14 is a line for making the gate electrode 2 lower in resistance, reference numeral 15 is line for making the common line 13 lower in resistance, reference numeral 16 is a line for making the line 12 lower in resistance which applies the voltage upon the counter electrode 4, with the line 14, 15 and 16 being formed simultaneously on the substrate 1. The same parts shown in FIG. 3 are designated with the same reference numerals in FIG. 6 with no description thereof being given.
A method of manufacturing the TFT-array in the present Embodiment will be described hereinafter. At first, the single layer film composed of either of Cr, Al, Mo, Ta, Cu, Ti, W, Al--Cu and Al--Si--Cu, and alloy among them, and transparent conductive material such as ITO or the like, or either of multi-layer films laminated with them is used to film at the same time as shown in FIG. 7(A) so as to form the line 14 for making the gate electrode 2 lower in resistance, line 15 for making the common line 13 lower in resistance, the line 16 (not shown) for making the line 12 lower in resistance for applying the voltage upon the counter electrode 4. An etching method where the pattern section becomes rectangular may be also used although the taper etching method where the pattern section becomes trapezoidal is used as an etching method in the simultaneous pattern-forming of the lines 14, 15 and 16.
Then, the gate electrode 2, the common line 13, the line 12 (not shown) for applying the voltage upon the counter electrode 4, the pixel electrode 3 and the counter electrode 4 for forming the electric field in a direction parallel to the substrate 1 face are formed simultaneously with the use of the single layer film composed of either of Cr, Al, Mo, Ta, Cu, Ti, W, Al--Cu, and Al--Si--Cu, and alloy among them, and transparent conductive material such as ITO or the like, or either of multi-layer films laminated with them is filmed as shown in FIG. 7(B) in shape so that the gate electrode 2 includes line 14 for making the gate electrode 2 lower in resistance, the common line 13 includes the line 15 for making the common line 13 lower in resistance, the line 12 for applying the voltage upon the counter electrode 4 includes line 16 for making the line 12 lower in resistance. The film of the layer is made as thin as possible so that the pixel electrode 3 and the counter electrode 4 may be formed in pattern with high precision. Also, the taper etching method may be also used, although the etching method of making the pattern end portion vertical is used as an etching method in the pattern formation.
Then, as shown in FIG. 7(C), the pattern of the amorphous silicon 6 and the amorphous silicon 7 with impurities being doped into it are formed in the position above the gate electrode 2 by successive deposition of the gate insulating film 5, the amorphous silicon 6 and the amorphous silicon 7 with impurities doped into it, and simultaneous etching of the amorphous silicon 6 and the amorphous silicon 7 with impurities being doped into it with the use of the etching resist formed by the photo-lithography. The gate insulating film 5 is made as thick as approximately 0.1 μm through 1.0 μm with the use of either of silicon nitride and silicon oxide, and the film oxide of the material of the gate electrode 2 and multi-layer film laminated with them. Also, micro-crystal silicon or the like with impurities such as phosphorus or the like may be also used, instead of amorphous silicon 7 with impurities doped into it.
As shown in FIG. 7(D), the contact hole 8 is formed in the gate insulating film 5 on the pixel electrode 3. The single layer film composed of either of Cr, Al, Mo, Ta, Cu, Ti, W, Al--Cu and Al--Si--Cu, and alloy among them, and transparent conductive material such as ITO or the like, or either of multi-layer film laminated with them is filmed as thick as approximately 0.1 μm through 1.0 as shown in FIG. 7(E) so as to form the source line 9 and the drain electrode 10 which are divided into two in such a manner as to be spaced with each other on the pattern of the amorphous silicon 7 with impurities doped into to it by the patterning. At this time, the drain electrode 10 is electrically connected with the drain side electrode 3 through the contact hole 8. Thereafter, the amorphous silicon 7 with impurities doped into it is removed with the portion covered with the source line 9 and the drain electrode 10 remaining. Finally, as shown FIG. 7(F), the transparent insulating film such as silicon nitride, silicon oxide or the like is formed on the entire face as a passivation film 11.
In the present embodiment, the TFT-array in connection with the channel-passivated thin film transistor forming method, instead of the channel etch type thin film transistor although the embodiment shows the combination between a TFT-array forming method for forming simultaneously with the gate electrode 2 the electrode forming the electric field in the direction parallel to the substrate 1 face and the channel etch type thin film transistor forming method.
The same effect is obtained by the formation of the gate electrode 2, the line 12 for applying the voltage on the counter electrode 4, and the line low in resistance in the lower layer of the common line 13 as even in the construction of the TFT-array in Embodiment 1 or Embodiment 2 although in the present embodiment is explained with the construction of the TFT-array of the Embodiment 3.
According to the present embodiment, the pattern width of the line portion where low resistance is necessary can be made smaller in a condition where the pixel electrode 3 and the counter electrode 4 for forming the electrode field in a direction parallel to the substrate 1 face where the high-precision and fine pattern formation is required, because the line low in resistance can be formed by the use of the low resistance material and the thicker film only in the line portion where the line resistance is necessary to be made smaller.
Embodiment 5
FIG. 8 is a plan view of one pixel element of the TFT-array showing Embodiment 5 of the invention. FIG. 9 is a sectional view of a portion taken along a line of C--C of FIG. 8. Referring to the drawing, reference numeral 17 is a removing portions of the gate insulating film 5 and the passivation film 11 in a region where an electric field is formed in the direction parallel to the substrate 1 face with respect to the pixel electrode 3 comb-shaped, and the counter electrode 4 opposite to each other. The same parts in FIG. 8 are designated by the same reference numerals in FIG. 6 with no description of the same parts being given. As the method of manufacturing the TFT-array in the present embodiment is the same as those in Embodiment 4, the description thereof is omitted.
The driving voltage for strengthening the electric field is required to be raised or the space between the drain side electrode 3 and the counter electrode 4 is required to be narrowed so that much higher precise pattern formation is required, because the strength of the electric field to be formed by the pixel electrode 3 and the counter electrode 4 is damaged by the formation of the gate insulating film 5 and the passivation film 11 on the pixel electrode 3 and the counter electrode 4 for forming the electric field. In the TFT-array in the present embodiment, the strength of the electric field is prevented from being damaged by the removing of the gate insulating film 5 and the passivation film 11 on the drain side electrode 3 and the counter electrode 4 for forming the electric field.
The TFR-array in the embodiment is etching removed in the gate insulating film 5 and the passivation film of the removing portion 17 which is the region where the electric field is formed after the formation of the passivation film 11 in the TFT-array formed as in the Embodiments 1, 2, 3 and 4. There are a method of removing all the gate insulating film 5 and the passivation film 11 as shown in FIG. 9(A), a method of removing with one portion of the gate insulating film 5 remaining after the removing of the passivation film 11 as shown in FIG. 9(B), a method of forming passivation film 18 thinner after the removing of the gage insulating film 5 and the passivation film 11 as shown in FIG. 9(C), as the construction of the removing portion 17.
The present embodiment can form the electrode field efficiently with the same driving voltage and without narrowing the space between the pixel electrode 3 and the counter electrode 4, because the strength of the electric field to be formed is not damaged by the removing of the gate insulating film 5 and the passivation film 11 on the pixel electrode 3 and the counter electrode 4 in a region where the electric field in the direction parallel to the substrate 1 face is formed.
Embodiment 6
FIG. 10 is a sectional view showing the liquid crystal panel of the liquid crystal display with the TFT-array of the present invention being mounted on it. Referring to the drawing, reference numeral 1a is a transparent insulating substrate such as glass substrate or the like. Reference numeral 19 is an alignment film. Reference numeral 20 is a TFT substrate. Reference numeral 21 is a black matrix. Reference numeral 22 is an overcoat layer. Reference numeral 23 is an opposite substrate. Reference numeral 24 is a liquid crystal. Reference numeral 25 is a polarization plate. The same parts in FIG. 10 are designated with the same reference numerals in FIG. 1 with no description of the same parts being given.
The alignment film 19 is entirely formed to construct the TFT substrate 20 after the formation of the TFT-array on the transparent insulating substrate 1a by the same method of Embodiment 1 through Embodiment 5. The black matrix 21 for shielding the light which causes the inferior display, the overcoat layer 22, the alignment film 19 are sequentially formed on the other transparent insulating substrate 1a to construct the opposite substrate 23. The TFT substrate 20 and the opposite substrate 23 formed in this manner are opposed to each other to construct the liquid crystal panel by the impregnating of the liquid crystal 24 between them and the pasting of the polarization plate 25 on the outside of both the substrates.
The present embodiment can provide the liquid crystal display, which is hardly lowered in contrast when the visual angle direction has been changed, is hardly inverted in the gradation level when the multi-gradation has been displayed, is even in display and is high in aperture ratio because of the adoption of a system where the direction of the electric field for applying upon the liquid crystal 24 is made parallel to the substrate face by the mounting of the TFT-array which is equal within the substrate in strength of the electric field in the direction parallel to the transparent insulating substrate 1a face, and is small in the area of the line and the electrode portion.
As described above, the present invention can provide a TFT-array which is equal within the substrate in strength of the electric field in a direction parallel to the substrate face and is smaller in the area of the line at the electrode portion, because the electrode can be formed finer with high-accuracy for forming the electric field in the direction parallel to the substrate face.
Also, the present embodiment can provide the liquid crystal display, which is hardly lowered in contrast when the visual angle direction has been changed, and is hardly inverted in the gradation level when the multi-gradation has been displayed, is even in displaying, and is higher in aperture ratio because of the adoption of a system where the direction of the electric field for applying upon the liquid crystal is made parallel in direction to the substrate face by the mounting of the TFT-array which is equal within the substrate in strength of the electric field in the direction parallel to the transparent insulating substrate face, and is smaller in the area of the line and the electrode portion.
While only certain presently preferred embodiments of the invention have been described in detail, as will be apparent with those familiar with the art, certain changes and modifications can be made without departing from the spirit and scope of the invention as defined by the following claims. | A TFT-array including a substrate, a gate electrode, a first and second electrode provided on the substrate simultaneously with the gate electrode, an insulating film formed on the gate electrode, the first and the second electrode, a semiconductor layer formed on the gate electrode in such a manner that the insulating film is interposed between the semiconductor layer and the gate electrode, a pair of electrodes, either of which is connected with the first electrode or the second electrode, said pair of electrodes defining a semiconductor element together with the semiconductor layer. | 6 |
This is a continuation-in-part of copending application Ser. No. 07/851,624 filed on Mar. 16, 1992, now abandoned.
TECHNICAL FIELD OF THE INVENTION
This invention relates to arrythmia reverting devices and, more particularly, to an improved method and apparatus for detecting an arrhythmia and providing electrical therapy to shock the heart back to normal sinus rhythm.
DESCRIPTION OF THE PRIOR ART
Many advances have recently been made in implantable pacemaker/defibrillator devices which allow these devices to recognize an abnormally functioning heart and to provide therapy in the form of one or more electrical discharges into the heart in order to shock the heart back to normal sinus rhythm. One example of such a device is disclosed in U.S. Pat. No. 3,952,750 issued to Mirowski, et al.
Despite such advances, there is still room for improvement in this field. In particular, the device must be capable of accurately identifying the presence of an abnormal heart rhythm; e.g., ventricular tachyrhythmia, ventricular fibrillation, etc. Moreover, not only is it imperative that the device recognize the presence of the arrhythmia accurately, but it is essential that the arrhythmia be confirmed prior to aggressive electrical therapy being delivered to the heart. Specifically, there is normally a period of time of up to 30 seconds from the time a ventricular tachyrhythmia or fibrillation is detected until the shock is delivered to the heart. The arrythmia could, for example, spontaneously revert during this time. The presence of the arrythmia must therefore be accurately confirmed at the end of this period of time, just prior to delivery of the electrical therapy.
Although it is difficult to detect and confirm arrythmias, the confirmation step is particularly troublesome when compared with initial detection. This is because large random variations in the magnitude of the ECG signal occur during the time period between detection and confirmation. If the amplitude of the ECG signal produced by the abnormal heartbeat decreases by too much, the device may determine that the arrythmia has reverted when it really hasn't. Conversely, if the ECG amplitude of the normal heartbeat increases even though the arrythmia reverts, the device will over-sense and confirm the presence of an arrythmia when, in fact, the arrythmia is no longer present.
Additionally, even in the initial detection step, problems with changing body resistance, lead characteristics, etc., hinder accurate measurements of ECG signals. Any error in the detection or confirmation of an abnormal heart rhythm results in either unnecessary electrical shock being delivered to the heart, or electrical therapy not being delivered when such therapy is needed.
It can be appreciated from the above that the need to accurately detect and confirm arrhythmias requires accurate and adaptive sensing and measurement of ECG signals. Indeed, the Williams et al. article, entitled "Automatic Implantable Cardioverter-Defibrillator Related Complications," Journal of the American College of Cardiology, Vol. 15, No. 2, abstract, page 55A February 1990, reports that 0.6% of deaths associated with implantable cardioverter defibrillators were due to sensing failure, and that 4.9% of non-fatal complications were due to over-sensing. More simply put, the implantable device must be capable of (1) accurately detecting an arrythmia even though the measured ECG signal resulting from such an arrythmia may be larger or smaller than the ECG signal from a previous arrythmia; and (2) accurately confirming an arrythmia even though the ECG signal may greatly and rapidly vary in amplitude from the time of detection until confirmation.
One technique for addressing the second of the above problems is described in U.S. Pat. No. 4,940,054 entitled "Apparatus and Method for Controlling Multiple Sensitivities in an Antitachyrhythmia Device", to Richard Grevis and Norma Gilli. In this device, the gain of the sensing system is increased prior to the confirmation point. This increase in gain increases the probability of confirmation. A potential problem with this arrangement is that if spontaneous reversion occurs after detection and prior to confirmation, but the normal sinus rhythm produces a signal which is slightly greater than normally expected, the detector may confirm the arrhythmia, even though such arrhythmia is no longer present. Such false confirmation results in unnecessary, and indeed possibly harmful, electrical shocks being delivered to the heart.
An additional prior art system addressed to the above problems is described in U.S. Pat. No. 4,819,643 to J. Menken. The Menken arrangement provides for automatic gain control of the signal being utilized to detect and confirm an arrhythmia. As the amplitude of the ECG signal varies, the gain of an amplifier detecting the ECG signal varies inversely. Thus, decreases in ECG amplitude are compensated for by increases in gain. However, even the Menken system does not fully solve the problem, as explained by Bardy et al. in the article, "Failure of the Automatic Implantable Defibrillator to Detect Ventricular Fibrillation", American Journal of Cardiology, Vol. 58, Nov. 15, 1986, pp. 1107-1108. Specifically, even though automatic gain control is present in the device, the gain cannot be adjusted fast enough to follow rapid fluctuations in the amplitude of electrocardiac responses which occur between detection and confirmation. Such rapid fluctuations are often present, for example, during ventricular fibrillation (VF). Indeed, Bardy et al. conclude the article by stating that there is a "limitation of an arrhythmia-sensing algorithm that depends on automatically adjusting the gain of an electrical signal to detect VF while that signal may be changing rapidly in magnitude".
In addition to the above systems, there are prior arrangements that have attempted to utilize digital storage techniques in conjunction with implantable pacing systems, although none are directed to the sensitivity adjustment problem. U.S. Pat. No. 4,716,903 to Hansen et al. ("Storage in a Device Memory") discloses an implantable device which utilizes digital storage and a compression algorithm so that a representation of an ECG signal may be stored and analyzed at a later time by a physician. Australian Pat. No. 8,823,170, issued to H. Lagergren and entitled "Pacemaker System", teaches the storage of an ECG signal on a rolling basis so that a finite window of samples is always available in memory. Finally, U.S. Pat. No. 4,913,146 issued to R. Decote, Jr. ("Cardiac Sense Amplifier with Pattern Recognition Capabilities") discloses a device which processes a filtered ECG signal by utilizing a microprocessor. From the processed and filtered signal, a set of cardiac waveform descripters is derived. These waveform descripters may then be stored in memory as a template. When another template taken at a later time differs from the stored template by a sufficient amount, it is determined that an arrhythmia or other abnormality is present.
SUMMARY OF THE INVENTION
The above problems of the prior art are overcome and numerous other advantages achieved in accordance with the present invention which relates to an improved apparatus for processing stored samples of an electrocardiogram (ECG) signal to more accurately detect and reconfirm the presence of an arrhythmia. Specifically, upon detection of an arrythmia by a relatively simple detection means, data samples representing a portion of an ECG signal are stored in random access memory (RAM). The portion of the ECG signal stored is large enough to contain several R-waves, i.e., at least two. A second and more precise algorithm operates on the stored samples utilizing advanced signal processing techniques which are well known in the art. The second algorithm is used to confirm the arrythmia just prior to delivering electrical shock to the heart. By utilizing a conventional technique to detect the arrythmia, power is conserved. The more precise and complex confirmation algorithm, which requires higher power consumption, is utilized only to confirm the arrythmia after detection, thereby minimizing overall power consumption.
In another embodiment, the signal processing algorithm may also be utilized to adjust the sensitivity of the arrythmia detector. For example, once a day, the algorithm can be utilized to count heartbeats for a period of time while the arrythmia detector does the same. If the arrythmia detector detects fewer heartbeats than the algorithm, the sensitivity of the arrythmia detector is increased. Conversely, the sensitivity of the arrythmia detector is decreased if it detects more heartbeats than the signal processing algorithm. Thus, the algorithm is utilized to improve operation of the arrythmia detector.
Advantageously, the confirmation algorithm is more precise than the conventional detection means in that the algorithm can better adjust for rapid signal amplitude variations, variations in lead resistance, etc. By storing a digital representation of a plurality of R-waves and performing a detailed analysis, not necessarily in real-time, a much more accurate determination of ECG activity can be obtained than that obtained from a conventional detection technique.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a microprocessor based system for implementing the method of the present invention;
FIG. 2 is an exemplary flow diagram showing the major steps of an algorithm for implementing the present invention; and
FIG. 3 is an additional flow diagram showing other portions of a preferred algorithm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram of an implantable pacing device in accordance with the invention. The device includes numerous amplifiers, detection modules, and other electronic components to be described hereafter. Additionally, the pacing device includes a high-energy shock system (HESS)17 for delivering defibrillating shocks to the heart when necessary.
Sensing amplifier 5 receives signals from conductors 3a and 3b, and amplifies the difference therebetween. This difference is processed by band-pass filter 7 to remove slow drifts and attenuate the amplitude of T waves in the signal from the sensing and pacing leads. The band-pass-filtered signal is then supplied to selectable gain amplifier 8,the gain of which is controlled by microprocessor 10 in accordance with theresult dictated by a signal processing algorithm.
Amplifier 12 is also arranged to receive signals from conductors 3a and 3b through sensing amplifier 5. Amplifier 12 provides the amplified signal todelta modulator 11 which samples the signal and provides a plurality of digital samples to microprocessor 10. A finite window of samples is provided for use by microprocessor 10 in the signal processing algorithm for determining the proper gain adjustments to be made to amplifier 8 and for detecting the arrythmia. Delta modulator 11 is also utilized to provide the samples to be processed for confirmation, as described below.
The pacing system also includes conventional elements such as a pacing module 4, working memory 18, and a power source 19. Telemetry means 16 is any of a variety of well-known arrangements of circuitry for telemetrically communicating with a physician's equipment located externalto the patient's body. Finally, high-energy shock system (HESS) 17 may be invoked as needed in order to provide defibrillating electrical shocks to the cardiac tissue via leads 2a and 2b if the pacing device determines that such shocks are needed.
Turning now to FIG. 2, shown therein is a flow chart which may be used in programming microprocessor 10 in order to implement the invention. The following description of FIG. 2 discusses how the algorithm is utilized toconfirm the arrythmia.
During normal sinus rhythm, the system is in a monitoring state. The delta modulator 11 is not sampling ECG signals, and the shock capacitors included in the HESS are not charged. The microprocessor may optimally be put in a standby mode during this time so that power consumption may be significantly reduced.
The flow chart in FIG. 2 is entered from the monitoring state upon the detection of a possible arrhythmia at block 21 by a primary detector (not shown) in the detection module 6. The settings and algorithm used by the primary detector are selected so that the detector is very sensitive, detecting all arrhythmias and numerous rhythms that are benign and do not need therapy. At decision block 22, a decision is made as to whether or not the rhythm detected as possible arrhythmia. If it is not a pssible arrhythmia, the program loops back to the input of block 21. If the rhythmdetected by the primary detector 21 is a possible arrhythmia, a "snapshot" of the electrocardiogram is acquired at block 23 and stored in the RAM memory of the microprocessor 10, and an arrhythmia analysis algorithm is initiated at block 24. The length of the snapshot portion of the electrocardiogram is determined by information from the primary detector. The memorized portion of the ECG signal is also stored in a separate part of microprocessor memory for later recall by, and display to, operators ofthe apparatus. In block 24, the snapshot is analyzed by the microprocessor and software algorithms as a secondary detector to determine whether a true arrhythmia is present. This arrhythmia analysis or secondary detection algorithm is significantly more specific than the primary detector. Following the analysis of the snapshot in block 24, a decision is made at block 25 regarding whether or not an arrhythmia is present in the snapshot. If no arrhythmia is present in the snapshot, the program loops back to the input of the primary detector block 21, returning the program to a monitoring state. If an arrhythmia is present in the snapshot, the program proceeds to block 31. The proper therapy required toend the arrhythmia and revert the heart to normal sinus rhythm is determined in accordance with a therapy strategy algorithm at block 31. For example, the therapy strategy algorithm may determine the parameters for the train of pacing impulses to be delivered to the heart, or the required energy for reverting the arrhythmia. Proper determination of the therapy to be delivered depends upon, among other things, the nature of the arrhythmia detected by detection module 6 of FIG. 1. A variety of well-known therapy strategies and algorithms are presently in use; the particular algorithm utilized may vary from system to system.
If the therapy strategy algorithm determines at decision point 32 that a defibrillating shock should be delivered to the heart, block 33 is enteredvia branch 32a and the defibrillation capacitors begin to charge. As the defibrillation capacitors begin to charge, the delta modulator 11 is activated and begins providing samples of electrocardiac activity for a predetermined time window. The time window is long enough to include multiple R-waves, and is represented in FIG. 2 by block 34, labelled "acquire ECG snapshot".
After an ECG snapshot is acquired, i.e., the predetermined time window has elapsed, all samples from delta modulator 11 are input to the arrhythmia analysis algorithm and processed accordingly as indicated in block 35. There are two main parts to the arrhythmia analysis algorithm. The first part extracts significant events from the sampled signal, as may be done utilizing the method given in co-pending U.S. patent application Ser. No. 851,524, filed Mar. 16, 1992. It is emphasized, however, that any method of extracting events may be utilized without violating the scope of the invention.
The second part of the algorithm is utilized to determine the present cardiac rhythm. This may be done utilizing a variety of straightforward techniques. For example, if N events are detected as represented by the samples in the window of time of the ECG snapshot and the snapshot is Y units wide, it can be determined that an event is occurring every Y/N timeunits. As cardiac rhythm increases toward tachyrhythmia and ultimately to VF, Y/N becomes smaller. Accordingly, it can be determined whether particular arrhythmias are present by comparing Y/N to a predetermined setof thresholds.
It is preferable that the ECG snapshot be acquired and analyzed at such time that the analysis is completed just prior to completion of the charging of the shock capacitors. For example, if the shock capacitors take 30 seconds to charge and the ECG snapshot takes 4 seconds to acquire and 10 seconds to analyze, then the system should begin acquiring the ECG snapshot just a little less than 16 seconds after the arrythmia is detected In that case, the 14 seconds for acquisition and analysis will conclude 30 seconds after detection. Since the shock capacitors begin charging immediately after detection and take 30 seconds to charge, the system will be fully charged just when the arrythmia is confirmed.
After the arrhythmia analysis algorithm is run, a decision is made at decision point 36 as to whether or not an arrhythmia is present in the analyzed ECG snap-shot. For example, the arrhythmia analysis algorithm could determine that ventricular tachycardia is present, ventricular fibrillation, etc.
If the arrhythmia analysis algorithm determines that normal sinus rhythm ispresent in the ECG snap-shot, the tachyrhythmia is deemed to have spontaneously reverted and processing proceeds along decision branch 36b and returns to the monitoring mode in which the system existed prior to the detection of an arrhythmia, as shown at block 37. Optionally, the episode may be logged in memory for later analysis by the physician who may read the data from memory telemetrically. Furthermore, prior to returning to monitoring mode, any charge on the shock capacitors is dissipated, the HESS is placed in the off state, and all elements return to a low power consumption mode.
If the presence of tachyrhythmia is confirmed at decision point 36, processing proceeds along branch 36a to decision point 38. Decision point 38 is, in effect, a simple programming loop which continues to cycle around upon itself thereby allowing time for the shock capacitors to charge. After such charge has occurred, control is transferred to block 50which delivers a shock to the heart in an attempt to revert the tachyrhythmia. After the shock is delivered, control is transferred to block 39 where the processor acquires another ECG snapshot. After this snapshot is acquired, the arrhythmia analysis algorithm is repeated at block 40 in order to determine whether the tachyrhythmia has reverted. Decision point 41 then transfers control to monitoring mode block 37 via branch 41a if the tachyrhythmia has reverted. The steps executed in monitoring mode 37 are the same as those previously described, e.g., lowerpower consumption, etc. If the analysis algorithm run at block 40 indicatesthat the shock delivered at block 50 was not successful in reverting the tachyrhythmia, then decision point 41 transfers control back up via branch41b to block 31 and the process of formulating a therapy strategy thereby repeats.
Having examined the sequence of steps executed when it is determined at decision point 32 that a shock should be delivered to the heart, the following discussion addresses the sequence of steps executed when it is determined that no shock should be delivered but, rather, that antitachyrhythmia pacing (ATP) should be administered instead. In this situation, branch 32b from decision point 32 is taken, and the proper ATP parameters are programmed into pacing module 4 of FIG. 1 as shown at block42. Before delivering ATP to the heart, blocks 43 and 44 acquire and analyze an ECG snapshot for the purpose of reconfirming the presence of the tachyrhythmia. Decision point 48 returns the system to the monitoring mode via branch 48a and block 37 if the tachyrhythmia is no longer present, i.e., spontaneous reversion has occurred.
If decision point 48 confirms the tachyrhythmia, branch 48b is taken and control is transferred to block 45 in order to deliver ATP. Blocks 46 and 47 then serve to determine whether or not the arrhythmia is still present,as previously described for block 39 and 40. Finally, decision point 49 returns the system to the monitoring mode via branch 49a and block 37 if the ATP has been successful in reverting the arrhythmia, but transfers control to block 31 via branch 49b for re-administering therapy if the ATPhas been unsuccessful.
FIG. 3 is a flow diagram of a gain adjustment algorithm which is utilized to adjust the gain of selectable gain amplifier 8 of FIG. 1 or, equivalently, the sensitivity of the arrythmia detector 6. The algorithm shown by the flow chart in FIG. 3 is run at regular infrequent intervals, e.g., once a day or less, and is used to allow the non-real-time signal processing to assist in adjusting subsequent initial detection of an arrythmia. Of course, the actual interval used could be selected by the physician and even varied using telemetric means.
When a timer (not shown) indicated that the proper amount of time has passed for a gain adjustment process to occur, the system will first checkto assure that no type of therapy, such as that described with reference toFIG. 2, is currently being delivered. Thus, the gain adjustment process canonly be invoked from the monitoring mode. The gain adjustment process is entered at block 70 of FIG. 3 by a signal from the timer. Control is transferred to block 71 which acquires an ECG snapshot in the manner previously described. The delta modulator used to acquire the ECG snapshotfor gain adjustment of amplifier 8 may be the same delta modulator as previously described. After an ECG snapshot is acquired, control is transferred to block 72 in order to run a gain check algorithm to determine whether the gain in amplifier 8 must be increased or decreased. One example of a gain check algorithm, although quite simplistic, is to simply count the number of heartbeats detected by the detection module 6. If the therapy strategy algorithm detects many more heartbeats than the detection module 6, it is assumed that the gain of the detection module 6 is too low. If there are many more detects from the detection module, a decision is made that the gain of the detection module is too high.
The algorithm used to extract events from the snapshot for the purpose of gain verification may be the same algorithm used for arrhythmia analysis. If decision point 73 determines the gain of amplifier 8 is acceptable, it transfers control to block 75 via branch 73a and the system returns to themonitoring mode. If, however, the gain is not correct, control is transferred to decision point 74 via branch 73b. Decision point 74 then increases or decreases the gain accordingly, utilizing branch 74a, block 77 and branch 78a in connection with increasing the gain, and utilizing branch 74b, block 76 and branch 78b in connection with decreasing the gain.
The gain of amplifier 8 may be increased or decreased in fixed steps. Each time it is determined that the gain should be raised or lowered, the gain is increased or decreased by one step. The steps are made small enough so as to avoid an unstable system which oscillates about the target gain point but which never stabilizes.
It is noted that the details of spectrum analysis, digital signal processing, and other related fields have not been described in detail herein. However, any of the multitude of algorithms available may be utilized in analyzing and extracting information from an ECG snapshot. Forexample, the original signal from which the delta values were derived couldbe reconstructed and a correlation used to match the resulting ECG to a template. A template could be one of a library of templates corresponding to different rhythms which may have similar rates but which respond most favorably to different electrotherapies. This would allow different therapies to be delivered for arrhythmias which have similar rates but different shapes. Other techniques may be used on the ECG snap-shots, suchas Fourier analysis, noise filtering, etc. The well-known text, Digital Signal Processing, by Oppenheim and Schafer (Prentice Hall, Englewood Cliffs, N.J.), describes a variety of still other signal processing techniques which may be utilized with the present invention. Not only can the signals be processed in non-real-time, but they may also be processed out of order. | An improved implantable pacemaker/defibrillator device in which a first and relatively simplistic technique is employed to detect an abnormal heart rhythm and a second more precise algorithm is utilized for the more difficult problem of confirming the arrythmia. Since the complex, higher power consuming device is utilized only for confirmation, overall power consumption is minimized. Optionally, the precise algorithm may be utilized periodically to adjust the sensitivity of the detection circuitry. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a Continuation-in-Part of U.S. patent application Ser. No. 10/775,459, filed on Feb. 10, 2004, by the same inventor, for MULTI-USE FLUID COLLECTION AND TRANSPORT APPARATUS, and for which priority under 35 USC 119(e) and 120 is hereby claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates generally to devices and constructs used to enhance subterranean drainage from building structures and entrenchments, such as walls, footings, foundations, as well as drainage from under garage and basement floors, where overburden of concrete exacerbates the collection of water. Specifically, this invention embodies a drain assembly improvement using a simplified support matrix that may be used with membranous covers, stone or other adjuncts. The matrix can sustain great overburden and is inherently pliable enough to be rolled and used as a flexible drain assembly (or “blanket-drain”) over and around structures that would otherwise have to be served by more cumbersome and costly drainage systems.
[0005] 2. Discussion of Relevant Art
[0006] It has long been a practice, in the construction industry, to provide some form of drainage to subterranean structures. Ground water seepage remains a problem in most non-arid regions of the world; and, building footings, garage floors (multi-level) and walls, facing surface and subsurface waters, have been most susceptible to water incursions. Many drainage devices have been provided, as well as adjuncts thereto, in order to provide adequate carry-off or transport of these undesired waters. Other patents, secured by the instant inventor, adequately cover the use of membranous coverings, such as filter fabric and impermeable sheeting. This paper will deal primarily with supporting structures for use with such coverings and expand on the basic concepts disclosed in the earlier, priority document.
[0007] Five disclosures are germane to this discussion, relative to the extant art: U.S. Pat. No. 3,965,686 ('686), issued Jun. 29, 1976, entitled DRAIN SHEET MATERIAL; U.S. Pat. No. 4,995,759 ('759), issued Feb. 26, 1991, entitled DRAINAGE TUBE CONSTRUCTION; U.S. Pat. No. 6,527,474 ('474), issued Mar. 4, 2003, entitled PAVEMENT DRAIN; U.S. Pat. No. 4,019,326 ('326), issued Apr. 26, 1977, entitled NONWOVEN HORIZONTAL DRAINAGE SYSTEM; and, U.S. Pat. No. 5,152,892 ('892), issued Oct. 6, 1992, entitled SPIRAL FILTER ELEMENT. All of these patents show, to some degree, the functionality of the coiled or spiral element in providing a conduit for fluids and having a relatively low or limited deformation character. However, it is in the careful study of each disclosure that one perceives, albeit suitability for intended purpose, its limitations when compared to the ready adaptability of the instant invention.
[0008] Issued to Saito et al., '686 details a compound sheet apparatus wherein a plurality of coils or internally strengthened tubules are parallel-arrayed, embedded in a non-woven fibrous material and disposed between two thin sheets of filter fabric. The apparatus' outer sheets are both porous and not suitable for placement against vertical walls. Most limiting is the necessity for the fibrous “filling” in which the tubules are embedded. When used for the specific purpose shown in '686, and notwithstanding the “filling”, the apparatus appears to enjoy some flexibility; however, it seems intuitive that doubling the thickness of the “sandwich” would render such flexibility problematical. A characteristic of its construction, the use and dependence upon flow direction-constraining fibers, obviates a bi-directional emplacement of the apparatus on surfaces that may change in pitch direction or present a configuration that will not allow the use of a constrained-flow device.
[0009] A single-purpose drainage tube, for use in entrenchments, is shown in '759. The apparatus consists of a length of drain formed by a fixed tangential connection of parallel, equal-length sections of tubing, on a longitudinal axis that is perpendicular to the axes of the sections. The tubing consists of corrugated pipe; and, the assembly is completed by enveloping the above apparatus in a filter fabric. Although more stylized emplacements can be conceived for the apparatus, it appears that in the vertical drainage mode, turning of corners is impossible because the longitudinal fixation denies flexibility, as defined and required by the instant inventor.
[0010] Although not intended to flex, the pavement drain member of '474 is remarkable in that it is essentially a plain resin coil, albeit composed of two arcuate strands in fixed adjacency. The coil possesses a minimal gap between each annular section so as to obviate infusion of macadam, when it is set onto the asphalt medium. Water will infuse readily into the coils and be transported from the tarmac base. The primary motivation for the use of a stylized resin coil is to provide a structure having high overburden sustainability, a tunnel-like effect for transporting fluids and a possession of pseudo-homogeneity with the tarmac. The latter characteristic obviates coil interference during destruction (by grinding) of the tarmac.
[0011] The subsurface soil drainage system of '326 employs a porous mat, of non-woven fibers, in which is centrally embedded a tunnel-shaped agglomeration of heat-spun filaments of spiral or coil geometries. Subsurface waters, infusing the mat, are carried off through the tunnel of filaments, thus draining the surrounding soil. This apparatus requires a considerable thickness (and amount) of non-woven mat, making it unsuitable for the purposes of draining most structures. It also appears to lack the degree of flexibility required by the instant inventor.
[0012] Final to this review of relevant art is patent '892, for a spiral filter element possessing a special expansion-compression character. It is essentially a filter-covered spring, the coils of which are formed so that the gaps between the (analogical) annuli gradually increase in size from one coil end to the other. This predisposition of the element assures that, when vertically and operatively oriented, each discrete section of the coil is capable of sustaining the mass of the coil sections above it. Placed in a horizontal position, the spring gap variations of this element would defeat its purpose in any planar filtration ensemble.
[0013] Although for the most part, structure and soil draining, with concomitant filtration, is still performed using tiles, large amounts of stone and paper/fabric overlay (such as in drywell and septic usages), it is the instant inventor's contention that conscientious builders should transition to more efficient, effective and reliable draining and filtering modalities.
[0014] The instant invention provides an easily manipulated, flexible device that can be emplaced both adjacent to and beneath concrete structures and earthen constructs, as well wrapped about articles such as pipes, cylinders, corners and generally planar surfaces.
INCORPORATION BY REFERENCE
[0015] Because they show both the present state of the art in drainage devices having an internally channeled structure, as well as disclosing filtering adjuncts or various stand-off mechanisms, U.S. Pat. Nos. 3,965,686, 4,995,759, and 6,527,474, with the aforesaid priority application, are hereby incorporated by reference.
DEFINITIONS
[0016] Generally throughout this disclosure, words of description and claim shall have meanings given by standard English usage; however, certain words—preponderantly nouns—will be used that may have a more stylistic (in bold-face) meaning and are defined as follows:
arrangement—herein, the placement of basic support elements of the invention that will compose a duct-like member; array—the order of two or more members, not necessarily planar; blanket-drain—a term of art used herein to refer to the assembly/ensemble for, or method of, providing below grade/structure drainage using the inventor's preferred and alternate planar array embodiments; construct—generally, an article or a building structure; continual—having intermittent, or periodic, breaks or discontinuities; continuous—having no breaks or discontinuities; continuum—suggesting a continuity of some feature, such as a covering; cross-link—the attribute of joining/communicating between support elements or members of the invention; coupling—herein, a physical fixed, rigid or movable linking of elements or members of the invention; duct—a unit used for fluid transport, having generally an axially void, elongated, skeletal appearance, and typifying the member of the invention; element—the basic constituent of the invention having a particular geometry (shape) that has ordinarily a central void, the void optional in arcuate or curved elements, and wherein the element itself comprises one or more of the geometries; gang(ing)—a group(ing) of elements, of any shape, into one or more configurations in order to arrange the resultant members into other than purely planar arrays; hoop—an element having (particularly) a generally circular geometry, also ring and annulus(lar) and, concatenated in a coil member; integral—necessary to complete or in itself complete; longeron—a longitudinal element that connects parts of a series, such as the centrally void, geometrical (elemental) parts of the invention; member—a part of the invention consisting of an arrangement of its constituent elements, generally in-line; membrane or membranous—of or pertaining to a porous/non-porous, thin sheet of material, irrespective of its composition, as opposed to mat or matted; nodule—a projection of indefinite shape that can be, simply, a detent or dimple; permeable—the quality of allowing a fluid, to pass through; polyform—any form, assembly or construct using support elements or members of the invention; quasi-tubular—the character of a support member that emulates a duct, but only to the extent that it is skeletal, elongated and sustains an axial void; rigid—a physical property of an object wherein the object substantially resists deflection in a particular dimension (direction) or plane; sandwich—the configuration made by placing one planar surface over, but set apart from a second surface, and wherein either may be virtual or referenced as face(s); skeleton(tal)—the arrangement of elements of the invention manifesting a multi-aperture character; stagger(ed)—the arrangement of members in a parallel posturing so that the elements of each may interleave with the other/others; Standoff—a spacing support element or device that facilitates the setting apart of articles, e.g., membranes or stone; stringer—generally, but not necessarily, an elongated structure that effects connection between the members (Cf. longeron); support—generally used as an adjective with elements and members of the invention; tubule—item (member) of the invention having a duct-like, skeletal appearance; unitary—having wholeness, as in a single unit or monolith composed of plural members.
[0046] The above listing is not exhaustive. Certain other stylized terms, used previously or hereafter, are defined at the time of their first usage or placed in quotation marks and used with conventional wording.
BRIEF SUMMARY OF THE INVENTION
[0047] The deficiencies and limitations of the earlier art, namely complexity, cost and, in most instances, inflexibility are overcome by providing an inexpensive, easily applied innovation that facilitates collection and removal (transport) of subsurface or sub-structural waters. Additionally, a continued rollup or wrap-around capability of the instant drainage assembly enhances it greatly in respect of packaging and shipping, as well as use in the field.
[0048] Critical to the synthesis of the invention is the use of discrete elements, of a generally circular (hoop) or common geometric definition. These elements are concatenated, to form a coil, or are placed in a coaxial arrangement along a membrane (fixed thereto) or integral with, and along, at least one longeron. Both of these constructs give the resultant (member) a duct-/tunnel-like or quasi-tubular/conduit shape and, when arrayed by parallel alignment or cross-linking, emulate a planar/blanket article that possesses excellent flexibility, provides exceptional overburden support and facilitates fluid transport, after its passage through the spacings in, about and between the elements.
[0049] Defined, in only the general sense, as planar/sandwich morphology, the invention consists of an array of the strong, firm, non-biodegradable members that are, in a pristine sense, configured as supportive, stand-off elements that optionally bear a porous (or impermeable) membranous covering of geo-textile filter fabric (or sheet plastic) on at least one face of the array. Depending on the use of this relatively flexible assembly, the other face of the array may bear the same type of membranous covering or no covering at all, save for an optional mesh. The latter (mesh) is employed, at a manufacturer's discretion, to enhance the structural integrity of the assembly and is apparent in but one modality of the invention as a crosshatch, or network, of longerons and/or stringers.
[0050] Members may also be fixed to the covering(s) by any adhesive suitable for a permanent, water-impervious and non-biodegradable existence; many are available throughout the automotive, construction and plastics industries.
[0051] With the invention, there is acquired not only a device that has unlimited in-ground use, with high overburden sustainability, but one retaining a high degree of flexibility that allows wrapping about an article/structure or compact rolling-up, for ease in handling, storage and shipment.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0052] Of the Drawings [Caveat—the following illustrations are for explanation only and no sizes nor dimensions should be inferred unless explicitly stated]:
[0053] FIG. 1 is a representation of the preferred embodiment for a standoff or support member of the invention;
[0054] FIG. 2 a representation of an alternate to the preferred embodiment of the standoff or support member of the invention;
[0055] FIG. 3 is a drawing of the FIG. 2 member having a structural reinforcement, termed a longeron;
[0056] FIG. 4 is a plan view of the FIG. 1 member, in-place and adjacent a compounded version (“doublet”) thereof;
[0057] FIG. 5 is an end elevation of the FIG. 4 assembly;
[0058] FIG. 6 is a plan view of the FIG. 2 member, in-place and adjacent a doublet version of the FIG. 3 member;
[0059] FIG. 7 is a plan view of an optional arrangement of one or both elemental embodiments of FIGS. 1-3 ;
[0060] FIG. 8 is an illustration of the confection technique for a small section of the invention sandwich assembly;
[0061] FIG. 9 is a drawing of a model of the invention, diminutive only in its surface area;
[0062] FIG. 10 is a sectionalized end elevation of the FIG. 9 model;
[0063] FIG. 11 is a sectionalized end elevation of the FIG. 9 model, bearing an optional partial covering;
[0064] FIG. 12 is an end view depicting the ability of the FIG. 9 device to negotiate an around-the-corner emplacement;
[0065] FIG. 13 shows an alternate construction of the preferred embodiment requiring no coupling membrane;
[0066] FIGS. 14A and 14B depict, respectively, the support elements preparatory to their engagement with a longeron of an adjacent member and a detail of the discrete element; while, FIG. 14C presents an end elevation of the FIG. 13 construct;
[0067] FIG. 15 shows the construct of FIG. 8 employing stringer(s), in lieu of coupling membrane(s);
[0068] FIG. 16 depicts a modification, a further compounding, of the FIG. 4 “doublet”, and FIG. 17 an end elevation thereof;
[0069] FIGS. 18 and 19 are correlative illustrations, respectively, of the FIGS. 16 and 17 modification in the staggered arrangement of compounded members;
[0070] FIG. 20 illustrates an arbitrary poly-formation of invention;
[0071] FIGS. 21 and 22 depict end elevations of suggested support elements (geometric shapes) of the invention, with optional bracing features;
[0072] FIG. 23 presents an end elevation of stacked members of the invention; and,
[0073] FIGS. 24 and 25 show, respectively, a plan view and end elevation of the FIG. 2 member in a compound construct.
DETAILED DESCRIPTION OF THE INVENTION
[0074] Before commencing this description, the reader is referred to the DEFINITIONS, given above. The materials of construction are well known in the industry and no further mention will be made of them other than that the filter fabric is in common usage, in sheet (“membrane”) and mat forms, and the support or stand-off members may be composed of any strong, non-biodegradable resin or polymeric, such as polyamide, polyester or polyvinyl chloride. In short, the physical characteristics of the materials comprising the standoff members should be heat-melt formable to facilitate manufacture by extrusion, casting or injection molding processes. The heat melt character also facilitates fusing of the various elements.
[0075] Referring now to FIG. 1 , there is depicted, in the preferred embodiment, a support/standoff member 10 of the invention. It is, substantially, a duct-like or quasi-tubular item comprised of a series of hoop or ring elements 12 that are axially aligned on and integral with a longeron 14 . The member is generally produced by injection molding as a unitary item. The particular annular shape is chosen because of its resistance to deformation likely to be caused by centripetal forces, such as overburden of soil or concrete.
[0076] The alternate support/standoff member is shown in FIG. 2 , and is described simply as a coil 20 . As is readily apparent, a series of hoops/annuli 22 are, by the nature of a coil, axially aligned, but not discretely closed. Although being made of similar material, the coil lacks the inherent strength of the preferred embodiment support member 10 because there is no structure to confine any one annulus to its median plane 23 . To compensate for a hoop's tendency to contract or expand out of it's median plane, the FIG. 3 modification is made. Therein, a longeron 24 ′, peculiar to the coil 20 , is added. Whereas the coil is readily made by extrusion techniques, the element of FIG. 3 requires secondary processes that require its alternate embodiment nomenclature, in the instant invention. As was discussed in the above discussion of relevant art, a coil without an intermediate support, such as the filler medium of U.S. Pat. No. 3,965,686, will simply be unable to sustain the great overburdens anticipated in most subsurface emplacements. It is, however, desirable and used where feasible, because of its inherent flexibility—generally as a cross-linking (entwinement) element or when adequately constrained (see FIGS. 7 and 24 ).
[0077] FIG. 4 introduces an optional use of the support member 10 D, also referred to as a “doublet”. The doublet is a cohesion of two member units 10 generally, but not necessarily, along their respective longerons 14 . Here, in plan view, the doublet is postured proximate the member unit 10 and parallel to it. Although not shown here, this unit may be axially rotated 180° and the hoops of the unit interleaved with those of the doublet. This arrangement is known as “staggered array”. It will be seen in the FIG. 12 description, concerning around-the-corner emplacements.
[0078] FIG. 5 presents an end elevation of the FIG. 4 array. The members 10 / 10 D may be arrayed in either unit, doublet or mixed assemblage; likewise they may be in parallel, staggered or non-staggered registry, so long as a close proximity is maintained, i.e., there are no intervening or intermediate constraints, such as filler materials. FIG. 6 shows a coil doublet 20 D, in plan view. It, along with its unit of FIG. 2 or 3 enjoys almost the same versatility and may be mixed with them, or with the preferred embodiment 10 in standoff arrays.
[0079] The aforesaid versatility is clearly seen in FIG. 7 , where a highly supportive standoff array 30 , comprised of a mix of the preferred embodiment 10 (in parallel arrangement), is cross-linked with the alternate embodiment 20 . The coil usage, in this array, neither uses nor requires the strengthening longeron. Other arrangements may be made of either embodiment, with the coil modality free of, or bearing, the longeron 14 ( 24 ′). In a production run, the actual arrangement of the hoop members 10 / 20 , as well as their mix and size, will be selected according to the function to be performed. For example, where a “pour through” of concrete is desired, spacing of elements to create voids in the array may be provided. A (small) model of such spacing S is depicted in the figure. Such a provision would, of course, necessitate removal and sealing of any covering, over and under the array at the selected void areas; such would be done in production or at the site of installation.
[0080] From a production standpoint, FIG. 8 shows the assembly of one aspect of the invention 40 (see, FIG. 9 : 40 ) to be straight forward: (1) the desired covering membrane 42 is laid or run out to receive, along desired and discrete portions thereof, a suitable adhesive A for fixing support members 10 ( 20 ) to it; (2) the adhesive is disposed on the membrane, in the selected array pattern; (3) the support members are joined to the membrane on the adhesive; (4) additional adhesive AA is deposited on the tops of the fixed members; and, (5) another layer of membrane is folded E( 40 ) over or otherwise placed onto the ensemble to complete the assembly. Such an assembly process is familiar to manufacturers.
[0081] Depiction is seen, in FIG. 9 , of a model of the assembled invention 40 . In this partial cut-away drawing, the supports/stand-offs are a mix of the preferred embodiment, in unit 10 and doublet 10 D modes. The membranous covering 42 is a geo-textile filter fabric, now used throughout the industry; it envelops the array. In some installations, and depending on the sizing of the production models, it may be desirable to concatenate the arrays of the invention 40 . This being the case, a connector 50 is provided to mate a tubular member with its corresponding member in the concatenated array (not shown). The connector consists of a straight tube 52 , a plastic or resin, that is designed to fit snuggly into the tubular members' hoops 12 ( 22 ). To assure that the tubes are not easily retracted during installation manipulation, a number of detents 54 are provided around the ends of the tube. Too deep an insertion, into the member, is precluded by the presence of a flange 56 , circumscribing the middle of the tube 52 . In most instances of use, an installer requiring concatenation to ensure continuity of fluid passage through the arrays, need only open ends of the invention, thereby creating “flaps”. Concatenation, using only a few of the connectors, can then be finished by sealing the flap ends over the adjoining assemblies. Alternatively, connectors need not be used if the covered, abutting ends of an assembly 40 are taped over with a durable, non-biodegradable adhesive or sealing tape.
[0082] Remaining drawings, FIGS. 10-12 , illustrate two options featured in the invention 40 / 40 A, with FIGS. 10 and 11 directed to covering options, and FIG. 12 , to a standoff arrangement. It will be noted that FIG. 10 shows the invention 40 , enveloped in the filter covering 42 over the top and bottom of the quasi-tubular array, which is comprised of unit 10 and doublet 10 D members. For the sake of clarity, no adhesive or alternate stand-off(s) are shown, in any of these three drawings, but it should be reckoned that any of the aforementioned features of the invention are, or could be, used.
[0083] FIG. 11 discloses another option in the invention 40 A. Here, a partial membranous covering of filter fabric 42 is complemented by a non-biodegradable, water impervious membrane 43 . This option finds utility, particularly, when the invention 40 A is to be placed onto a surface that is to be sealed against water infusion, e.g., outside basement walls. The amount of actual overlap O/L depends on a particular usage, manufacturers preferences and the membrane bonding techniques to be used.
[0084] FIG. 12 shows an end elevation of the invention featuring yet another optional arrangement of standoff/support members 10 and 10 D. The inventor's specifications call for a parallel arrangement of quasi-tubular supports in near or close proximity, that is, eschewing any filler medium between adjacent supports and yet fully contemplating a physical communication between these members (ibid. FIG. 7 ). In FIG. 12 , the referenced optional arrangement is termed a parallel, interleaved I/L disposition. The arrangement is simply an alternating, forward-back (“staggered”) placement of the supports, of either type (two doublets shown) throughout the array, in pre-selected periodicity. This option facilitates an easier folding or bending of the invention around a corner, thus allowing sharper turns in its placement. Of course, adjustments in either adhesive application (fixture) or membrane looseness may be necessary for such a feature; but they are well within the competence of modern manufacturers.
[0085] It should be recognized that the fundamental aspects of this invention can be realized with, for example, quasi-tubular stand-offs of different nomenclature, such as rigid, perforated pipes/tubules/rods—but, flexibility may be lost to some degree; a trade-off for the ability to sustain heavier overburdens (see, e.g., FIG. 20 and description).
[0086] The clear advantage of using the standoff elemental structures of the invention is seen in the fact that the gap between adjacent hoop planes ( FIG. 2 : 23 ), of either embodiment, can exceed the nominal thickness of the discrete hoops. Such advantage is not shared by the multitude of extant drain tubes. Also, reading this disclosure, one may rightly infer that the planar array ( FIG. 7 ) may take on any planar geometry, flex to the degree allowed by stand-off size and arrangement, and be covered by both permeable/non-permeable membranes, on either one or both faces of the array. Used not merely to facilitate around-the-corner installation, as depicted in FIG. 12 , the interleaved element arrangement, in either embodiment 10 / 20 , is used by the inventor to augment the support members' strength. This strengthening becomes necessary under very high overburden conditions and, as an option, provides a dual function to the interleaving practice.
[0087] Having discussed the fundamental aspects of the invention, it becomes incumbent upon this inventor to offer the reader some insight as to the versatility inherent in the use of the invention's tubule/duct members 10 / 20 , as well as their hybridizing potential with rods, perforate tubes and other drainage adjuncts. The latter portion of this disclosure is therefore directed to the combinational modalities that become apparent once the invention is understood.
[0088] Turning now to FIGS. 13-14C , the basic interlinked mode 60 of members 10 is acquired by encirclement of the longeron 14 (hoop) of one member 10 by the elements 12 of the adjacent member; the end elevation of this modality being shown in FIGS. 14A (open) and 14 C (closed). The hoop elements are made in the manner of a book ring binder, in that they are a relatively thick, but bendable polymer. As shown in FIG. 14B , the hoop elements 12 are afforded breaks to facilitate opening, for the potential encirclement of a longeron 14 of another member ( FIG. 14A ). Subsequently, the elements are closed and a snap-in detent 15 is inserted into depression 13 , thus securing the encirclement.
[0089] FIG. 15 is an illustration depicting an array 40 (M) akin to that of FIG. 8 , but lacking the coupling membrane—in favor of stringer 14 ′ coupling. The number, as well as dimensions, of stringers used will depend on manufacturers and users objectives. This embodiment will find high value in installations that require in situ preparation of the drainage system. This matrix can be cut and stacked, after many a fashion, and covered with stone and/or fabric. The various options shown in FIGS. 16-20 are particularly suitable for such installations.
[0090] Referring specifically to FIGS. 16 and 17 , there are seen, respectively, a modification 10 (M) of the FIG. 4 “doublet” and an end elevation thereof In orthogonal extension from off the common longeron 14 , the uniquely distinct, multiple element 12 nonetheless has the same characteristics as a singular geometric shape of the FIG. 4 article. The multiple elements can be made by casting, molding or by stamping and cementing/fusing C/F the individual shapes or members. FIGS. 18 and 19 differ from the previous two drawings only in that one of the elemental arrangements is staggered with respect to the other. In both variations of this modification, the elements can be readily extended by concatenating the geometric shapes outward in their same (common) plane. As will be seen in the following drawing, one is not restricted to a simple planar array, nor a single type element.
[0091] The flexibility in design and assembly of this invention can be better appreciated with reference to FIG. 20 . Here an end elevation of a poly-formation (“polyform”) 10 (P) of the invention reveals a “U” formation of the elements 12 ′. Using the invention to its fullest potential, and in keeping with all disclosure made herein, one readily sees that the various elements and members can be had to form many varied formations such as “L”, “T”, “U”, “V”, “W”, “X” and “Y” patterns and combinations thereof; these patterns effect “oblique-planar” structures and can be formed using cementing or fusing C/F.
[0092] Aside from the fact that, in FIG. 20 one planar array is no longer co-planar the other, but in an angular relationship (oblique plane) therewith, a very great distinction is presented in the geometric shapes themselves. The preferred embodiment, arrays of coils or tubules, the latter using elements created by employing geometric shaped articles, is by now quite familiar. Although a plan view is not shown, FIG. 20 and its description suffice to explain, in conjunction with the invention structures now known, namely FIGS. 8-12 , how the familiar three-dimensional matrix plane (ordinary planes or oblique intersecting) is acquired using other structures, with or without the heretofore disclosed elements/members. FIG. 23
[0093] The reader's attention is called to the members R/D of FIG. 20 . As an option, these may be solid discs (the D) used with the ring or hoop shapes 12 . Moreover, in a totally different modality, these R/D members are polymeric rods (the R), to be used in conjunction with the shown G/T elements, which consist of tubules 10 (the G) or perforated tubing (the T). The resultant array is essentially planar, somewhat less flexible, capable of sustaining much greater overburden than the designs of FIGS. 1-19 .
[0094] Turning now to FIGS. 21 and 22 , there is shown, respectively, a circular or arcuate element 12 and a rectilinear. The novelty shown here is the structural reinforcements 13 , which may be indicated when the invention is designed to sustain heavy burdens such as rock/stone or concrete.
[0095] FIG. 23 discloses employment of the devices of FIGS. 21 and 22 using members of the invention 10 , but crafted with two longerons 14 and the interleaving technique. This stacking of elongated members contemplates a larger scale installation in ditches, against subsoil walls and the like. The invention appears here in a more massive form and is usually assembled member-by-member, in situ; thus, the elements bear reinforcement structures 13 .
[0096] Final to this disclosure, FIGS. 24 and 25 show in plan view and end elevation, respectively, an embodiment 70 alternate to the preferred, using the plain coil 20 . Two or more such coils are intertwined by a spiral threading of one through the other. The result is a flexible, adjustable planar matrix characteristic of the invention. As with all embodiments herein, this also may be cloaked with the earlier designated membranous covers.
[0097] Improvements of this invention and applications thereof, according to the disclosure, are commended to the field consistent with the appended claims. | A non-biodegradable, unitary drainage device of flexible character. The invention features a monolithic, skeletal construct consisting of stacked, planar or poly-formational arrays of quasi-tubular, tube or rod supports, termed “stand-off” elements. Actual positioning of the supports in their arrays is varied, with parallel interleaving, cross-linking and intertwining of supports to acquire varying degrees of strength and flexibility. Depending on specific function to be performed, optional covering sheet(s) of differing materials, that provide either particulate filtering or fluid impermeability (sealing), may be used with the various matrices. A different modality is also shown, wherein rods are mixed with tubules or perforated tubes to acquire the analogous structures, for use with great overburdens of stone or soil. | 4 |
PRIOR APPLICATION
The present invention claims priority from, and is a continuation application of, U.S. patent application Ser. No. 10/670,545 filed Sep. 24, 2003, which is related to, and claims the benefit of U.S. Provisional Patent Application Ser. No. 60/420,712 filed Oct. 23, 2002, which is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
The disclosures of the foregoing applications are herein specifically incorporated by this reference in their entirety. The present invention claims the benefit of U.S. Provisional Application Field of the Invention.
The present invention relates, in general, to distribution and sales channel management for goods and services and, more particularly, to software, systems and methods for improving the resolution and usefulness of data related to direct and indirect sales channel participants and activities used for channel management.
RELEVANT BACKGROUND
Efficient distribution of products is fundamental to an effective economy. As used herein, “products” include both goods and services. In many cases, distribution makes up a significant if not majority portion of the final cost. Hence, efficient distribution leads to higher profits and lower consumer prices. Moreover, efficient distribution tends to lead to higher consumer satisfaction and greatly reduced waste of resources, time, and money used to distribute the products. Various alternative distribution channels have been implemented to address the limitations of the retail channel. In direct sales channel a supplier creates their own marketplace and sells directly to the consumer. This gives the supplier a great deal of control and promises to reduce distribution costs. However, direct sales are a poor substitute when the marketing costs of reaching consumers and drawing them into the marketplace are sizable. As a result, the marketplace created by direct sales channels tends to be orders of magnitude smaller than the marketplace created by distribution channels.
Both consumers and businesses purchase products through distribution channels. Business-to-consumer channels and business-to-business channels are similar with the notable exception that business-to-business channels typically lack a retail outlet where goods/services are exchanged directly with a purchaser. In addition, business-to-business transactions often require a higher level of expertise and increased interaction between the seller and buyer. As a result, business-to-business channel participants rely more heavily on an efficient and accurate distribution channel. In both cases, however, many channel participants such as the producer, sales personnel, distributors, and the like may lose visibility of the activities of other participants. For example, it remains difficult for a manufacturer or producer to obtain information about the purchaser when a product is delivered to a post office box, loading dock, or first to a channel partner, who in turn delivers the products or services to a customer at a later time. After the initial transaction, the producer loses visibility of important distribution channel details.
The process of distribution generally involves actions taken to get products into a relevant marketplace where a consumer or end user makes a purchase decision. Sales and marketing personnel often initiate a transaction by taking and scheduling customer orders for goods and services. Production, stocking, product movement, and shipping activities occur to fulfill orders, but these activities often occur independently and in anticipation of orders. Hence, an order may be fulfilled by a shipment from any of a number of warehouse locations, and a salesperson or producer must rely on information from the distribution site to know where, when, and how order fulfillment occurs. Distribution channels may be multiple-tier (e.g., distributors and resellers) and, as a result, further obscure information relating to the end-customer from other channel participants.
At the same time, a customer may have several apparent identities. Many businesses operate under several names, or names that are abbreviated in different ways, and so will appear as different businesses to a distribution channel. Frequently, a business will have multiple delivery addresses either for different locations, or to implement internal distribution channels. For example, a corporate headquarter's address may have little or no relation to a loading dock address used for deliveries, or a post office box address used for customer returns. As a result, a salesperson may be dealing with one business apparent identity while a shipper or warehouse is dealing with a separate apparent identity. Hence, it may be difficult to match captured information to information used by sales/marketing personnel, producers, and other channel participants.
Because the distribution chain may obscure some data about the end-customer, the supplier loses a great deal of information related to buyer behavior. For example, a direct sales person responsible for an account may be unaware of sales made to a subsidiary of the customer that uses a different name, or is at a different address than the main account address known to the sales person. Such information would be useful to manage sales representative compensation, future production, product design, and marketing efforts, as well as to determine sales achievement levels for various organizational entities to determine whether business objectives were met. Hence, suppliers share the desire for product distribution solutions that make precise data about distribution chain events available to interested parties.
SUMMARY OF THE INVENTION
Briefly stated, the present invention involves a system for managing a product distribution channel involving a plurality of participants acting as producers, consumers, and conduits for the distribution channel. At least one of the plurality of participants is imprecisely identified. Spatial information records are combined with captured channel information to specifically identify the channel participant who is imprecisely identified.
In another aspect, the present invention involves a method for gathering data from a distribution channel in which a transaction record related to a distribution channel event is generated. The transaction record comprises transaction data identifying at least one channel participant. The transaction record is processed by geocoding location data within the transaction data to determine a spatial identifier for the transaction record. A reference record database is accessed using the spatial identifier to identify one or more reference records having spatial data that is similar to the spatial identifier associated with the transaction record.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows information relationship in a distribution environment in which the present invention is implemented;
FIG. 2 illustrates exemplary data records suitable for processing in accordance with the present invention;
FIG. 3 shows a functional block diagram of an information resolver according to an embodiment of the present invention; and
FIG. 4 illustrates relationships in a matching process in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides, among other things, a system and method that enables customer or channel participant “roll-up” for accounting and aggregation purposes. Although a significant focus is to provide channel information with greater precision and granularity, it should be appreciated that such precision enables one to aggregate channel information with greater accuracy to manage information with less granularity. This allows transactions to be identified with higher-level organizations (through business rules) that can be determined through relationships in the business information reference data.
The greater precision allows for clustering of business information by any organizational node in a corporate tree identified through reference database relationships. The present invention provides for clustering/association/aggregation of transactions based on common business identities at any level of a tree, for the purposes of sales aggregation, behavior analysis, product traffic analysis, etc.
FIG. 1 illustrates information relationships in an exemplary distribution system that supports product distribution from a producer/manufacture 101 to various customers 102 . Transaction information, designated by an encircled “i” in FIG. 1 , comprises various types of information captured by channel participants such as resellers 103 and distributors 104 . Although not illustrated, channel information may be captured directly by producer/manufacturer 101 themselves in which case the data resolution enhancement processes and mechanisms, in accordance with the present invention, may be implemented by producer/manufacturer 101 internally.
Transaction information may comprise electronic data interchange (EDI) messages, flat files of a standardized or proprietary format, database records, spreadsheets, XML records, or other available format for communicating information about transactions. The transaction records contain some identification of the customer name, and some locality or location information, as well as implementation specific information (e.g., model number, sub-account information, pricing, etc.) about one or more transactions that are associated with the transaction record. Significantly, the present invention does not require that the customer name and/or location information be entirely accurate or high in precision. One feature of the present invention is an ability to compensate for common errors and deficiencies in the transaction record by improving the resolution of the data as described below.
Some of the difficulties encountered in channel information capture include improper and inconsistent coding or formatting. For example, in electronic data interchange (EDI) systems a common difficulty is that state abbreviations appear in a postal code field. EDI records may lack “sell-from” information, invoice dates, and the like. The nature of this data thus makes it difficult to match the EDI record with other records maintained by channel participants such as sales records attributed to a particular market segment or sales person. Also, many distributors 104 and resellers 103 may use a single customer identification for multiple customer locations, which again makes the records difficult to match with other channel information. A large percentage of records have systematic errors introduced by coding procedures and/or typographical errors introduced by data entry personnel.
Other errors include incorrect sold-to names that identify an individual at a business rather than the business itself, or identify a subsidiary or other business related to the customer. Business names are often entered in a very inconsistent manner with abbreviations, department names/numbers, truncation, and other techniques used that may be convenient to a particular channel participant (e.g., a delivery person) but make the records difficult to interpret and match to other channel information.
FIG. 2 illustrates common errors in channel information records that make precise identification of a customer difficult. Similar errors occur in identifying other channel participants such as resellers 103 and distributors 104 . FIG. 2 illustrates this with transaction records involving educational institutions. Each line item in FIG. 2 represents an exemplary transaction record, although the form and content of transaction records is expected to vary widely. The first transaction record involves The Johns Hopkins University. However, because all of the records suffer a systemic error in that the letter “s” was replaced with the letter “x”, the entity name is uncertain. Moreover, the address indicates a particular branch of the university, and does not correspond to the administrative or business address. In accordance with the present invention, these deficiencies are overcome by using the location information (e.g., address, postal code, city/state information and the like) to select one or more reference records from a database of known information. This spatial matching using location information may identify one or several business entities in the area. Lexical matching against this relatively small subset of candidate businesses will likely identify a single reference record associated with The Johns Hopkins University Hospital, which is the business identity that is in fact involved in the transaction represented by the transaction record in FIG. 2 .
In the second transaction record in FIG. 2 , in addition to the systemic typographical error, the business name is identified as a department, with the institution name (i.e., Arizona State University) abbreviated. This record is further confused by the placement of the state code in the postal code field, which is a common error. Again, the present invention uses the available location information to select candidate businesses and then can use lexical matching to narrow the candidate businesses to one or a very few businesses with a high probability of being a proper match. The third record illustrates a transaction record in which the ship-to address is missing completely, while the final record illustrates a situation in which the business name itself is truncated to a degree that it, at best, ambiguously identifies the channel participant.
Returning to FIG. 1 , gateway 106 provides a mechanism for communicating channel data to resolver 105 . Gateway 106 may comprise a special-purpose gateway processor such as an EDI gateway machine or a more general purpose mechanism such as a file transfer protocol (“FTP”) directory that is monitored by resolver 105 . In other alternatives, gateway 106 comprises a web site where data can be entered or off-loaded using any available data transfer technique. Gateway 106 may receive data as files, XML documents, electronic mail, or other message format.
The present invention involves a resolver 105 , which may be implemented in hardware, software, or hybrid systems, that processes transaction records to specifically identify the customers, distributors, resellers, or other participants that are imprecisely identified by the transaction record. An imprecisely identified participant means that through error or design, the transaction record cannot be matched with certainty to a known business entity. This uncertainty may be caused, for example, by typographical errors in the record, use of a trade name or trademark rather than the business entity name, inaccurate or missing address data, and the like. It is not necessary that all transaction records be imprecise because so long as even a small percentage of records are imprecise, the record cannot be used by itself to reliably identify the participant. In other words, even a low percentage of imprecise transaction records casts doubt on the veracity of all of the transaction records, even those transaction records that specify the associated business entity exactly and accurately.
Resolver 105 receives transaction records and parses the records to identify business name information. Resolver 105 also identifies the location information within a transaction record. Resolver 105 implements several processes alone or in combination with each other to improve resolution of the transaction record. These processes include 1) geocoding the location information from a transaction record; 2) using the geocode information to identify or select one or more candidate reference records from a pre-established reference record database; 3) lexical processing of business name and/or address information obtained from a transaction record; and 4) matching the transaction record to a reference record database. In this manner, the present invention uses both spatial analysis/matching and lexical analysis/matching to create an association between a transaction record (which may contain errors) to reference records (which presumably contain fewer errors and higher resolution).
In many cases the processes performed by resolver 105 , shown in greater detail in FIG. 3 , cooperate to identify and select a single candidate reference record that can be matched to the transaction record. However, it is recognized that it is not always possible to automatically resolve an ambiguous or erroneous transaction record to a single reference record. Accordingly, it may be necessary for subsequent automatic and/or manual processes to be engaged to finally select a single reference record or otherwise improve the resolution of the transaction record to a satisfactory level. In this manner, the present invention will operate to either automate or assist in the process of matching transaction records to reference records.
The geocoding process may be implemented by a process or series of processes that transform data that indicates a real-world geographic location to a code or value (e.g., latitude/longitude) that is representative of that real-world geographic location. Hence, a street address can be transformed by a variety of algorithmic and look-up table methods into a latitude/longitude associated with that address. Similarly, a zip code, phone number, city, state, and other information can be transformed into a geocode value. The geocoding process does not have to generate a specific point location as it may define a zone of locations of any size and shape around a particular set of location information. Hence, while the examples herein suggest using a street-level accuracy for the geocoding process, it is contemplated that in some applications the accuracy may be defined to a zip-code-level, neighborhood-level, or city-level and still be useful in accordance with the present invention.
It should be noted that the reference records include location information such as geocodes as well. Unlike conventional raw business data that may be obtained, for example, from Dun and Bradstreet or other business information providers, a reference record is processed to associate a geocode (or a zone defined by a pattern of geocodes) with the business data. Even where the business data includes some location information such as an address, or even a latitude/longitude, it may be desirable to process the provided information such that each record is associated with reliable, accurate location information As both the transaction record and reference record are associated with geocodes, the geocode can be used to link a transaction code to one or more reference records. For example, when a spatial zone is associated with the reference record, a search of reference records to obtain a list of reference records in which the geocode of the transaction record falls within the zone of a reference record may be used.
In cases where the geocode matching described above results in more than one reference record match, the present invention further contemplates lexical matching of information in the transaction record to business information in the reference record to further refine the set of reference records. Lexical matching refers to any of a variety of matching techniques that leverage knowledge of the rules, syntax, and content expected in a particular data type. For example, lexical matching of company names can take advantage of knowledge of common company abbreviations and acronyms such as “Inc.”, “Corp.”, “Ltd.”, “LLP”, and the like to provide more accurate matching. Similarly, common abbreviations and errors (e.g., using a trademark instead of a business name) can be used in the matching process. Essentially, a lexical match involves determining a score that quantifies the degree to which two strings or values match each other. Potential matches can be sorted by score, and potential matches with sufficiently high scores can be deemed matches for purposes of further processing.
For example, in a transaction involving a business entity named “MallMart, Inc.”, a transaction record might indicate a business name of MALL MART; MallMart, Inc.; MM Inc.; MMI; or the like. Other transaction records might indicate “The Photoshop at MallMart”, which should also be associated with Mallmart, Inc. At the same time, some unrelated records may exist such as a transaction identifying “Mall Drugs” where the unrelated transaction records may or may not be in the same geographic area as MallMart, Inc. In these cases, spatial matching in accordance with the present invention will identify matches for all businesses that are located at a similar address (e.g., a Nordstrom's, a Cookie Hut, or any other business) as well as a record for the target company “MallMart, Inc.”. Various lexical techniques can be used to score the similarity of “MALL MART”, “MM Inc.”, and “MMI” against the multiple candidate reference records to specifically identify the “MallMart, Inc.” reference record, while at the same time discarding any reference to Mall Drugs, even if this business is located geographically close to MallMart, Inc. Lexical matching can provide much more sophisticated processing to compensate for common spelling or coding errors as well as systemic errors in entering the names in the transaction records. Even so, it is expected that in some cases an entirely automated identification will not be possible, and a human operator will be required to identify or discard matches for some records, although this task will be greatly simplified.
FIG. 3 illustrates resolver processes 105 in greater detail. Essentially, resolver 105 receives transaction records (labeled “T-RECORD” in FIG. 3 ) such as EDI records, point of sale (“POS”) flat files, or other format transaction records from the client gateway 106 using any available data transport processes 301 such as FTP or web upload in the particular example. Data may be physically transported (e.g., by magnetic/optical tape, magnetic/optical disk, etc.), and/or may use any available network protocol. In particular implementations, transaction records are validated and parsed in component 303 to extract information that will be used for the matching process in accordance with the present invention.
In some embodiments of the present invention, a domain-specific or customer-specific learning process is employed by component 305 to continually improve matching as shown in FIG. 3 . A learning database 307 is used to store records related to specific learned matches, and is searched using the transaction information in a manner akin to other database searches taught by this specification. The learning database is populated with information obtained whenever a high-confidence match is made either automatically by participant identification processes 309 or manually by manual identification processes 311 . In this manner a system can be configured to continually learn from instances where the automated processes 309 resolved a transaction with a high degree of confidence, or did not resolve a transaction record with sufficient precision and so matching was referred to manual identification processes 311 . For example, when a channel participant operates under a trade name that bears little relation to the business name, manual intervention may be required with or without the assistance of end-user, partner, and product exception resolution tools 312 . Using the learning database 307 , a record can be created that creates an association between the trade name and the business name, thereby enabling subsequent occurrences of the trade name to be automatically processed by participant identification processes 309 and manual operations 311 / 312 to be avoided.
The processes for developing a learning database 307 involve, for example, learning particular abbreviations, common misspellings, product names, trade names, and other implementation specific information that causes difficulty in precisely identifying a channel participant from a transaction record. The algorithms compensate for domain-specific, company specific, and/or systemic difficulties in transaction records thereby increasing the reliability of the downstream matching processes. These algorithms can be implemented quite flexibly, or omitted altogether, to meet the needs of a particular application.
In the particular example, when attempting to resolve a new transaction, processes 305 use the learning database 307 before either automatic or manual resolution processes so that knowledge from previously identified transactions is reused. While the overall representation of customers and other transaction entities is highly fragmented and disparate across participants, any given participant does tend to repeat the information associated with a given entity the same way in successive transactions. In one embodiment, learning database 307 is essentially subdivided to keep track of previously learned/identified patterns on a per-participant basis, or on a group of participants, or other rational sub-division that limits the scope of the pattern recognition to be within a particular group of reports only. In this way, a conservative algorithm that avoids false matches is implemented to reuse past identifications for all transactions going forward in an efficient manner.
Learning database 307 can have both exact match patterns and regular expressions mapped into its records. Therefore it is useful in identifying not only data items that have been entered into a partner's Enterprise Resource Planning (“ERP”) system correctly, but also data items that have been entered incorrectly. For example, if the company US Reprographics was entered into a partner system as US Repreographix, it would likely go through a manual process to confirm when that data item was first encountered. In addition to identifying it with the right company, a record would be entered into learning database 307 that would automatically identify the same misspelled entity and the same address in the future as the correct entity. Learning database 307 can also be used to perform broader matching using regular expressions where needed. For example, any transaction with “Taco Bell” as the only words (using any spelling or other punctuation) would be directly mapped to a specific entity.
In a particular implementation there is also a process in place to allow self-pruning of learning database 307 . Since the learning database 307 serves as a lookup, it is undesirable for entries to go out of date relative to the business mapping (e.g., to a Data Universal Numbering System (“DUNS”) number). For example, when a first company acquires a second company the learning database may require adjustment to purge stored knowledge. The present invention contemplates algorithms that operate periodically or occasionally to “clean out” learning table 307 for a given business when any part of its business tree changes (e.g. if it is involved in a merger or acquisition), or if the business state changes (business goes out of business, etc.). It is thought to be better to flush any potentially affected learning records and have the next instance of the entity go back through the manual process rather than try to do anything automatically since often in M&A activity, brand names may be consolidated, split, or even sold off, which may make prior learning on these records obsolete. However, automated processes may be useful in some circumstances to adapt learned matches in a manner that adapts to the change in business state.
Participant identification component 309 includes end-customer identification processes, partner identification, and other participant identification that involve the use of location information from the transaction records to select one or more reference records such as business information records 313 (e.g., from a Dun & Bradstreet (“D&B”) database), customer-managed data such as a partner profile database 315 , or the like. In particular implementations, text or other matching processes 319 are used to correct/validate the transaction-specific information in a transaction record by referencing customer product catalogs, pricing, or similar data 317 . While these processes further resolve the transaction records in the spirit of the present invention, they do not directly involve the combination of spatial information in most cases. The result of the various processes shown in FIG. 4 is the matching of one, and in some cases more than one, reference record to the transaction record being processed.
The present invention may be better understood with reference to a particular example shown in FIG. 4 . This example contains many specific features that are not to be construed as limitations of the broader invention, however, the specifics are useful in improving understanding of the invention.
In this example, a Transaction Record 401 is defined by the following attributes:
Name,
Street1,
Street2,
City,
State/Province,
Country, and
Telephone number
In this example, a Reference Database consists of one or more Reference Record (e.g., D&B database). A Reference Record 403 is defined by: (e.g. A record for a DUNS number)
Unique Reference Identifier (e.g., DUNS number),
Name (e.g., Business Name for the DUNS number. There might be more than one name given a Reference Number, such as tradestyle, DBA . . . etc.),
Street1,
Street2,
City,
State/Province,
Country,
Telephone,
Latitude, and
Longitude (Latitude and Longitude are, in this example, at street level (i.e., accuracy down to the building)).
An exemplary decision process involves:
1.
Given a Transaction Record 401
Using Street1, Street2, City, State/Province, and Country field to find a
geo-location.
When it is possible to geocode the address information to a desired
resolution (e.g., street level), the geocode is retained.
Otherwise, the geocode failed.
2.
When the geocode for the transaction record is determined, use the
geocode to select a list of candidates from the Reference Database so that
each candidate has a matching latitude and longitude as the transaction
record.
3.
When there is only one candidate, perform lexical matching using name of
the transaction record with all the name variation of the candidate. Lexical
based name matching first standardizes the name (such as standardizing
common abbreviations (e.g., INC., LLP . . . etc), removing words that do
not help in discrimination (e.g., and, or . . . etc), standardizing common
business abbreviations (e.g., P&G = Proctor and Gamble . . . etc)). Once the
names are standardized, a score is computed based on the similarity using
an algorithm similar to dynamic programming.
When the best score is greater than some pre-defined threshold, assign the
candidate's reference number to the transaction record, and consider the
transaction record to be matched.
4.
When more than one candidate is returned from step 2, perform the lexical
matching on the names as defined in step 3 between the transaction record
and all the candidates. In addition, attempt to find other identifiers in the
street record to match the Suite/Floor information to help identify the
correct candidate.
When the best score is greater than some pre-defined threshold, assign the
reference number of the candidate with the best score to the transaction
record, and consider the transaction record to be matched.
5.
When a match is not found in Step 3 or Step 4, and there is a valid
geocode, retrieve a list of candidates from the Reference database within a
pre-defined radius of the Transaction record's geocode value.
Perform the lexical matching on the names as defined in step 3 between
the transaction record and all the candidates.
When the best score is greater than some pre-defined threshold, assign the
reference number of the candidate with the best score to the transaction
record, and consider the transaction record to be matched.
6.
When a match is not found in Step 5, try other combinations; this is
because, often times, the data is not filled correctly in the transaction
record. For example, when the name is placed in the street 1 field and the
address is placed in the street 2 field. In this case, swap the fields and
return to Steps 2-5.
7.
When there are no matches found after Step 6, use supplementary
algorithms and/or manual matching processes.
The reference record database includes a plurality of reference records 403 where each record corresponds to, for example, a business entity such as a customer, reseller, distributor, or the like. The reference record 403 contains precise information about the associated business entity including precise address information and any other information that can be used by one or more of the distribution channel participants. For example, a reference record may contain a sales person ID to specifically identify a sales person that should be credited for a particular transaction. Significantly, the reference records contain sufficient precision to satisfy the needs of the channel participants.
The present invention is specifically illustrated in terms of distribution channels. However, the invention is readily applied to any hierarchical business relationship and not limited to channel relationships. Although the present invention is readily implemented in automated systems, it is contemplated that various operations and actions may be performed manually or semi-automatically to meet the needs of a particular application. For example, a human being may be familiar with selecting from a list of candidates to identify suitable matches for a particular transaction record as well as this matching being implemented in an automatic/algorithmic manner such that matches exceeding a certain score or meeting some acceptable pattern of scores provide a basis for a match. Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the combination and arrangement of parts can be resorted to by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter claimed. | Disclosed are methods for processing distribution channel data integrating business information with geographic data to produce integrated data, wherein the integrated data has greater resolution than the business information. Distribution channel data is captured and correlated with the integrated data to increase the resolution of the distribution channel data. | 8 |
FIELD OF THE INVENTION
This invention relates to plowing equipment. More particularly, it relates to a support system for a mid-chassis, underbody plow or scrapper system that controls the deployment of a blade and its storage beneath the vehicle for deployment. The invention is suited especially for installation on the underbody of trucks for use as snow plows.
BACKGROUND TO THE INVENTION
Mid-chassis or underbody plows and scrappers are well known vis. U.S. Pat. Nos. 4,031,966; 4,337,832. Such plows have been designed to fold upwardly for storage, c.f. U.S. Pat. No. 4,031,966 depicting rearward folding.
In designing an underbody plow or scrapper with a folding blade it is desirable to provide adjustability to raise or lower the blade, and to tilt the blade, raising its outer ends up and down about a horizontal axis that is generally pointed outwardly from the blade surface. Blades are often required to be angled to the left and right about a vertical axis. It is also desirable when the plow blade is light, to provide a supplementary force-control mechanism that will apply a downward force to the plow blade to maintain it in contact with the surface being plowed with the appropriate level of pressure. It would be highly desirable to combine these features with an under body plow having a storage feature that would permit it to be raised above the road surface when not deployed.
These features of control should ideally be achievable, in whole or in part, at minimal cost and with a minimal addition of weight to the vehicle.
It is therefore an object of the invention to provide an underbody blade support system that has various combinations of the above features combined with simplicity and low cost.
The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.
SUMMARY OF THE INVENTION
The invention employs a plow assembly incorporating an underbody plow blade or scrapper with a mold board and two outer ends, (hereafter referred to generally as a scrapper blade) which is mounted to extend generally transversely beneath the chassis of a vehicle. This scrapper blade is positioned between the forward and rearward sets of wheels on the vehicle and may be angled to be oriented to the left or right while still extending generally transversely beneath the vehicle.
A feature of the invention is that the blade may be folded, preferably forwardly, to raise it above the road surface in a stored position. In its folded orientation, the mold board of the plow is upwardly directed. Preferably, rotation of the mold board from its deployed position is effected about a hinge line that is rearwardly of and intermediate the top and bottom edges of the mold board. The top edge may, in being folded, retire from a first deployed rotational stop means to a second folded stop means against which the top edge may bear.
Preferably, the blade-folding system of the invention is carried by an elevating support to cause the folded blade to retire upwardly. Thus, in a preferred arrangement, the blade may be carried at the end of a pivot arm assembly in the form of two trailing arms that are mounted to the chassis so as to extend downwardly from a forwardly-mounted hinge mount. The upper edge of the mold board may nest in a recess formed in the pivot arms. The pivot arm assembly hinge mount allows rotation of the pivot arm assembly about an axis that is also generally transverse to the direction of motion of the vehicle. Other means of supporting and elevating the blade are, however, permissible, in order to provide this two-stage storage effect.
The scrapper blade is preferably tiltable in the sense that one of its two outer ends may be elevated vertically with respect to the other end. This may be effected in one preferred manner by providing a rotatable coupling between the vehicle chassis, e.g. within the pivot arm assembly, and the scrapper blade that allows the scrapper blade to rotate about a generally horizontal axis extending forwardly and rearwardly beneath the vehicle. Other means of providing for such freedom of motion may also be employed, including independently hinged pivot arms.
Preferably the scrapper blade with its scrapping edge is positioned against a road surface by two pressure actuators respectively located between the blade and the vehicle chassis at spaced locations on either side of the centerline of the vehicle. These pressure actuators may be in the form of pneumatic bladders to apply a resilient downward pressure on the scrapper blade through the elevating support. In the case of the use of a pivot arm assembly, the pressure actuators may be positioned between the chassis and the pivot arms.
As an optional feature, by independent control of the pressure actuators, differing vertical forces may be applied to the respective outer ends of the scrapper blade. Consequently a greater amount of contact pressure may be maintained between the scrapper blade and the surface being scrapped at one outer end of the blade than at the other outer end. This greatly facilitates the removal of snow, ice or other debris from a road surface when the level of material to be removed is higher on one side of the vehicle than on the other side of the vehicle.
The preferred type of pressure activator is a pneumatic bladder of the type generally employed in air springs. Their role is to press the blade edge resiliently against the road surface, lifting-off ice, snow and debris from that surface. Such devices are not only relatively inexpensive, but also provide a “spring” resilience that allows the scrapper to move vertically to accommodate vertical variation in the surface being scrapped.
To complement the folding action by which the scrapper blade is raised for storage above the road surface, the elevating support, e.g. the pivot arm assembly, may be provided with a blade folding actuator coupled between the pivot arm assembly and the vehicle chassis to serve as well as a lifting actuator. Action as a lifting actuator may be achieved in conjunction with the folding of the blade by providing a lifting link, such as a chain, that extends between a folding portion of the blade and the vehicle chassis.
The foregoing summarizes the principal features of the invention and some of its optional aspects. The invention may be further understood by the description of the preferred embodiments, in conjunction with the drawings, which now follow.
SUMMARY OF THE FIGURES
FIG. 1 is a side view of a prior art vehicle carrying a mid-chassis, underbody plow blade carried by a pivot arm assembly that serves as one aspect of a preferred variant of the invention when combined with a folding plow blade;
FIG. 2 is a perspective view of a cut-away portion of the vehicle of FIG. 1 taken from the left rear quarter with the pneumatic actuators omitted for clarity;
FIG. 3 is the view of FIG. 2 with pneumatic actuators depicted in position;
FIG. 4 is a rear-end view of the vehicle of FIG. 1 with the pivot arm assembly lowered;
FIG. 4 a is a rearward view of the vehicle of FIG. 1 with the pivot arm assembly raised;
FIG. 4 b shows a rearward face view of the tilting plate assembly;
FIG. 5 depicts the vehicle of FIG. 2 with the air distribution and control system in place;
FIG. 6 is a plan view of the folding blade configuration of the invention;
FIGS. 7 a and 7 b are side views of the blade of FIG. 6 respectively deployed and folded for storage;
FIGS. 8 a and 8 b are side views along the blade respectively when deployed and when folded;
FIG. 9 is a detailed view of FIG. 8 a showing the stored view of the blade of FIG. 8 b in ghost outline;
FIG. 10 is a plan view of a folding blade configuration of the invention having separately hinged pivot arms to provide the pivot arm assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 a vehicle 1 having a chassis 2 , forward wheels 3 and rearward wheels 4 carries between these sets of wheels 3 , 4 a scrapper blade or plow blade 5 . While reference hereafter will be made to a “blade” 5 this language is intended to encompass any form of scrapper blade, including rake and chisel-like constructions.
FIG. 1 is prior art. However, FIG. 1 will be described in detail because it provides a synergistic environment for the folding blade feature of the invention.
The blade 5 is carried by a pivot arm assembly 6 having two pivot arms 6 a, 6 b that trail below the chassis 2 from pivot arm hinges 7 coupled to the chassis 2 at the forward end of each pivot arm 6 a , 6 b serving as chassis mounting means. The hinges pivot arm 7 permit rotation of the pivot arms 6 a , 6 b about an axis that is transverse to the direction of the vehicle 1 . The pivot arms 6 a , 6 b may be mounted to rotate independently (not shown) to permit the blade 5 to tilt. An alternate, preferred tilting arrangement is detailed further, below.
Positioned between the chassis 2 and blade 5 are two pneumatic bellows 9 a , 9 b respectively mounted on opposite sides of the centerline 10 of the vehicle 1 . Based on pneumatic springs, these bellows 9 a , 9 b act as controllable pressure actuators which are able, in a preferred arrangement, to apply independently differing pressures to the outer ends 11 a , 11 b of the blade 5 .
A preferred structure for allowing the blades to tilt, i.e. to effect vertical displacement of the outer ends 11 a, 11 b of the blade 5 , is shown in FIGS. 2-5. For simplicity of depiction, the blade folding feature of the invention is not shown in FIGS. 2-5. Tilting is effected by the presence of a rotary coupling 12 incorporated into a pair of transverse tilting plates 13 a , 13 b. A first one of these plates 13 a extends between the pivot arms 6 a, 6 b; the second of these plates 13 b extends between two blade support arms 14 a, 14 b that connect to the blade 5 . A central pin 15 coupled to the two tilting plates 13 a , 13 b permits rotation of the blade support arms 14 a, 14 b and blade 5 about a horizontal axis that is generally aligned with the direction of travel 10 of the vehicle 1 .
The plates 13 a, 13 b preferably are positioned closely together so that their outer ends may brush together to absorb dislocating forces that tend to swivel the blade 5 to the left or right. As well, welded pins or bolts 45 may extend from the ends of one plate 13 a to carry containment plates 46 that contain or “trap” the outer ends of the second plate 13 b (or in the reverse arrangement extending from the second plate 13 b to contain the first plate 13 a ). This is to absorb tensional forces while permitting rotation between the plates 13 a , 13 b. Specific bearing surfaces may be provided with respect to each of the plates 13 a , 13 b to absorb the brushing contact action.
In FIG. 2 the alternate position of the tilted blade 5 is shown in ghost outline 5 a with one end 11 b raised and the other end 11 a lowered.
In FIG. 3 the pneumatic bellows 9 a , 9 b omitted from FIG. 2 for clarity are shown positioned to apply force between the chassis 2 and the blade 5 through the respective blade support arms 14 a, 14 b. These pressure actuators 9 a , 9 b are spaced apart and positioned to apply similar or differing pressures at the outer ends of the blade 5 in pressing the blade downward onto a road surface 36 .
The pivot arm assembly 6 may be raised by chains 16 descending from a frame 17 that includes a transverse bar 18 that overlies a further air spring lifting bellows 19 positioned on the chassis 2 . The pivot arms 6 a, 6 b according to this lifting arrangement are coupled to the chains 16 at locations between their ends to provide the action of a third class lever.
To raise the blade 5 , the pressure in the pressure actuator bellows 9 a , 9 b is released (through valves 24 ) and that in the lifting bellows 19 is increased. The force of the lifting bellows 19 is transmitted through the frame 17 and chains 16 to the pivot arm assembly 6 raising the blade 5 upwardly off of the surface being scrapped. This operation may be seen in FIGS. 4 and 4 a wherein the pivot arm assembly 6 is respectively lowered and raised. An alternate lifting arrangement may be employed with the folding-blade configuration, described further herein.
The control system for the blade support is depicted in FIG. 5. A source of pressurized air 21 , depicted as an air tank, provides air to a pressure distribution box 22 . Pressurized air is directed from this box 22 to the lifting bellows 19 and pressure actuator bellows 9 a , 9 b, through air lines 23 in response to manually set input signals, preferably originating remotely from within the vehicle cab. Exhaust valves 24 , responding in cooperation with the operation of the pressure distribution box 22 , exhaust or vent air from bellows 9 a , 9 b , 19 when they are to be depressurized, e.g. venting lifting bellows 19 when pressure actuators 9 a , 9 b are pressurized. Manometers 25 display the pressure conditions within the system.
Through the pressure distribution box 22 , controlled levels of pressure may preferably be developed independently in each of the bellows 9 a , 9 b controlling the scrapping effect of the blade 5 on the road surface. A different pressure need not necessarily be applied through the bellows 9 a , 9 b; but such option is available.
The folding-blade feature of the invention is shown in plan view in FIG. 6 . To assist in perceiving the positioning of the plow components, the wheels 3 , 4 are depicted at disembodied locations in FIGS. 6, 7 a and 7 b.
In FIGS. 6, 7 a and 7 b the tilting plates 13 a, 13 b have been shifted forwardly under the vehicle, to a location proximate to the pivot arm hinges 7 . In this arrangement, the pivot arms 6 a , 6 b are greatly shortened and the blade support arms 14 a , 14 b are greatly lengthened. The freedom of action provided to permit the blade 5 to tilt is, however, the same in principle as described previously. For the further discussion following herein, the blade support arms 14 a , 14 b will be addressed as forming part of the pivot arm assembly 6 .
In FIG. 6 the blade 5 is fixed transversely to the chassis 2 at an angle, e.g. 28 degrees, out of alignment with the vehicle. The blade 5 is carried by the two support arms 14 a , 14 b and respective air bladders 49 a , 49 b are positioned to develop a downward thrust upon such arms 14 a , 14 b.
The blade 5 has its own blade hinge axis 30 and is positioned by a cylinderical actuator 31 mounted on a transverse bar portion 32 of the pivot arm assembly 6 . A linearly actuated shaft 33 extends from the actuator 31 to join with the blade 31 at a blade-actuator hinge 34 . The blade hinge axis 30 is behind the blade 5 , positioned intermediate of the upper edge 32 and the scrapping edge 37 of the blade 5 .
The dual folding action of the blade 5 is shown in FIGS. 7 a and 7 b which respectively depict blade 5 as deployed and folded upwardly for storage. It will be noticed that, as a preferred feature, the support arms 14 a , 14 b are also swung upwardly from their deployed position, in FIG. 7 a, to their storage position, in FIG. 7 b, when the blade 5 is folded upwardly with mold board 5 a of the blade directed upwardly. The upward swing raises the arcuate portion 39 of the arms 14 a, 14 b closing-up the difference 50 , 50 a shown in FIGS. 7 a , 7 b.
In FIGS. 8 a and 8 b, details of the blade-folding action are shown in side view, looking endwise along the blade 5 . In FIG. 8 a the blade 5 is deployed with its scraping edge 35 positioned on a road surface 36 and its upper edge 37 bearing against a blade-deployed rotational stop surface 38 positioned on arcuate portion 39 of the support arms 14 a, 15 b of the pivot arm assembly 6 . The shaft 33 of the actuator 31 is fully extended, having carried the upper edge 37 of the blade 5 to the stop surface 38 . Thus the rotational stop surface 38 absorbs the obstructions encountered by the blade 5 on the road surface 36 , rather than the actuator 31 .
In FIG. 8 b the blade 5 is shown as folded, the upper edge 37 having passed rearwardly beneath arcuate portions 39 of the support arms 14 a , 14 b upon retraction of the shaft 33 (not visible in FIG. 8 b ) to rest against folded-blade stop surface 38 a. Rotating about blade hinge axis 30 , the lower, scraping edge 35 is elevated above the road surface 36 to present the mold board 5 a of the blade upwardly once the upper edge 37 reaches the folded-blade stop surface 38 a.
To achieve a double-action lifting effect with a maximum economy of components, a linkage in the form of a chain 40 extending between the blade 5 and chassis 2 is tightened by the retraction of shaft 33 and the forward rotational advance of the lower half of the blade to which it is connected to serve as a blade elevating means. The action draws the support arms 14 a , 14 b upwardly towards the chassis 2 . The corner 41 formed on the transverse bar portion 32 of the pivot arm assembly 6 may be strengthened and shaped to permit the chain 40 to slide around this corner 41 during this lifting action. A stopping arm 58 connected to the transverse bar 32 rises until it abuts a chassis rest 51 , limiting further upward travel of the blade 5 and pivot arm assembly 6 .
As shaft 33 is not in an intersecting alignment with hinge axis 30 , the linear actuator 31 is mounted to the transverse bar portion 32 by a swivelling support means that rotates about actuator axis 42 (indicated as to its location in FIGS. 8 a, 8 b ). Thus the actuator 31 has differing orientations in FIGS. 8 a and 8 b. The difference in these orientations are shown in FIG. 9 wherein a ghost outline 31 a shows the actuator 31 when the blade 5 is in its stored position.
FIGS. 1 through 5 depict an environment in which the folding blade 5 of FIGS. 6 through 9 may be installed. In FIG. 10 the pivot arm assembly 6 is shown as being attached to the chassis 2 by independent hinge joints 53 as chassis mounting means. These joints 53 , optionally of the Torrington type, allow the pivot arms 14 a, 14 b to rotate independently. This dispenses with the need for tilting plates 13 a, 13 b.
As shown in FIG. 10, a side surface (not numbered) of the stopping arm 58 may bear against a portion of the chassis 2 to limit sideways displacement of the blade 5 and pivot arms 14 a, 14 b.
The combined effect of both folding the blade 5 to direct its mold board 5 a upwardly and swinging the support arms 14 a , 14 b upwardly allows the blade 5 to be stored with maximum elevation under the chassis 2 . This is highly desirable as it allows the vehicle to travel at high speeds over uneven road surfaces 36 with reduced risk that the stored blade 5 will contact a protruding portion of the road surface 36 or strike an object lying on the road.
The use of air-activated pressure actuators 9 a , 9 b renders the blade support of the invention light in weight and less costly than hydraulic systems. The light weight of the blade 5 and pivot arm assembly 6 is supplemented by pressure applied through the bellows 9 a , 9 b , 49 a , 49 b which respond resiliently to variations in the height of the road surface 36 . The rotary coupling 12 of the tilting plates 13 a , 13 b in the pivot arm assembly 6 , or the use of flexible Torrington-type joints 53 , allows the scrapper blade 5 to adjust to the contour of the road surface 36 in the preferred variants of the invention. The angled orientation of the blade 5 allows debris to be transferred to the left or right side of the vehicles. Individually and collectively an improved means is provided for clearing a road surface.
Conclusion
The foregoing has constituted a description of specific embodiments showing how the invention may be applied and put into use. These embodiments are only exemplary. The invention in its broadest, and more specific aspects, is further described and defined in the claims which now follow.
These claims, and the language used therein, are to be understood in terms of the variants of the invention which have been described. They are not to be restricted to such variants, but are to be read as covering the full scope of the invention as is implicit within the invention and the disclosure that has been provided herein. | A mid-chassis, underbody plow or scrapper blade is mounted under a vehicle chassis to be folded upwardly for storage when not in use. The blade is also mounted to permit the outer ends of the blade to move vertically. Pneumatic pressure actuators mounted on either side of the center line of the vehicle apply pressure through pivot arms to the respective ends of the blade to control the scrapping action. The support structure for the blade swings upwardly to achieve a two-stage storage which increases the elevation of the blade when folded. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application 60/539,327, filed Jan. 26, 2004, and is related to the following co-pending applications: U.S. patent application Ser. No. 09/929,877, filed Aug. 14, 2001; U.S. patent application Ser. No. 10/232,993, filed Aug. 29, 2002; U.S. patent application Ser. No. 10/251,912, filed Sep. 20, 2002; and PCT Patent Application PCT/IL02/00996, filed Dec. 10, 2002. All of these related applications are assigned to the assignee of the present patent application and are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to computer networks, and specifically to methods and systems for protecting against denial of service and worm attacks in computer networks.
BACKGROUND OF THE INVENTION
In a Denial-of-Service (DoS) attack, an attacker bombards a victim network or server with a large volume of message traffic. The traffic overload consumes the victim's available bandwidth, CPU capacity, or other critical system resources, and eventually brings the victim to a situation in which it is unable to serve its legitimate clients. Distributed DoS (DDoS) attacks can be even more damaging, as they involve creating artificial network traffic from multiple sources simultaneously.
In order to launch an, effective DDoS attack, an attacker typically attempts to control a large number of servers on the Internet. One approach to gaining such control is to use “worms,” which are malicious programs that self-replicate across the Internet by exploiting security flaws in widely-used services. Worm infections are often invisible to the user of an infected computer, and the worm may copy itself to other computers independently of any action taken by the computer user. After taking control of a computer, the worm often uses the computer to participate in a DDoS attack, without any knowing collaboration on the part of the computer user. Infected computers that participate in this sort of mass malicious activity are referred to herein as “zombies.”
The present invention will be more fully understood from the following detailed description of the embodiments thereof, taken together with the drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram that schematically illustrates a computer network system, in accordance with an embodiment of the present invention;
FIG. 2 is a flow chart that schematically illustrates a method for protecting against DDoS attacks, in accordance with an embodiment of the present invention; and
FIG. 3 is a message flow diagram that schematically shows details of a method for authenticating a source of incoming packet traffic, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
Many DDoS attacks use “spoofed” IP packets—packets containing a bogus IP source address—making it difficult for the victim network to identify the source of the attack. In response to this problem, the above-mentioned related applications describe methods that may be used to determine whether the IP source address of an incoming packet is authentic or spoofed. Traffic from authentic IP addresses may then be passed on to its intended destination, while packets with spoofed addresses are blocked.
Zombies, however, may have legitimate IP addresses (belonging to the infected source computer), and anti-spoofing measures may therefore fail to filter out the packets generated by such zombies during a DDoS attack. Thus, in a typical attack, many zombies may succeed in establishing TCP connections with a victim server, and then may use these connections to bombard the server with messages, such as HTTP requests.
Embodiments of the present invention provide methods for resisting this sort of attack, by distinguishing legitimate messages from messages sent by zombies. For this purpose, some embodiments of the present invention enable a network guard device to challenge sources of incoming packet traffic so as to determine whether the sources comply fully with higher-level communication protocols, such as HTTP (including features of HTML) or DNS, which operate above the transport layer (typically TCP or UDP). Failure of a computer at a given source IP address to comply with the higher-level protocol indicates that the source may be a zombie, and incoming packets from this source are therefore blocked.
FIG. 1 is a block diagram that schematically illustrates a computer network system 20 , in accordance with a preferred embodiment of the present invention. A Web server 22 communicates with clients 24 via a wide-area network (WAN) 26 , typically the Internet. To prevent DDoS attacks on server 22 , a guard device 27 intercepts incoming HTTP request packets from network 26 that are addressed to server 22 . Guard device 27 comprises a guard processor 28 , which performs the various protection and authentication methods described herein, and a network interface 29 , which communicates with other components of system 20 and with WAN 26 . The guard processor checks the IP source address of each packet that it intercepts against reference values stored in a, database 30 or other data structure. Methods for generating these reference values—indicating which requests are legitimate, and which may have originated from spoofed IP addresses or from zombies—are described further hereinbelow. The guard processor blocks illegitimate requests from passing through to server 22 .
The configuration and operation of guard device 27 are shown and described herein by way of example, and alternative configurations and modes of operation will be apparent to those skilled in the art. For example, rather than being connected in-line with server 22 , as shown in FIG. 1 , guard device 27 may be connected in other configurations, for example, by a “lollipop” connection to a router (not shown) that forwards packets to server 22 . Alternatively, functions of the guard device may be integrated into the router or server or into other network equipment, such as a firewall. These and other possible operational configurations of the guard device are described in the above-mentioned related applications. Note that although guard device 27 is shown and described herein as protecting a single server 22 , in practice one or more guard devices of this sort may be deployed to protect a group of computers, such as a cluster of servers or an entire LAN. Additional deployment scenarios for the guard device(s) (not necessarily zombie-based) are described in the above-mentioned related applications.
Typically, guard device 27 comprises a general-purpose computer, which is programmed in software to carry out the functions described herein. The software may be downloaded to the computer in electronic form, over a network, for example, or it may alternatively be supplied to the computer on tangible media, such as CD-ROM. Further alternatively, guard device 27 may be implemented in dedicated hardware logic, or using a combination of hardware and software elements.
FIG. 2 is a flow chart that schematically illustrates a method that is carried out by guard processor 28 for protection against DDoS attacks, in accordance with an embodiment of the present invention. The guard processor may perform its packet screening and verification functions at all times, or it may alternatively filter packets only under stress conditions, in which a DDoS attack on server 22 is suspected. In order to determine whether an attack may be in progress, guard processor 28 intercepts incoming traffic via network interface 29 and monitors selected statistical characteristics of the incoming traffic that is directed to server 22 , at an attack detection step 50 . For example, the guard processor may use one or more of the following criteria to detect a zombie-based DDoS attack:
Number and distribution of source IP addresses—A sudden change, such as an increase in the number of different source IP addresses attempting to communicate with the server, may be indicative of an attack. Distribution of user agents specified in HTTP requests—The agent field in the HTTP request is optional, but it is usually used to specify the type of browser submitting the request. A sudden change in the distribution of agents may indicate that a large fraction of the requests are being submitted by zombies, which specify a particular agent as dictated by the malicious program that is controlling them. (In order to limit the amount of malicious traffic that can reach server 22 , guard processor 28 may optionally determine, in the absence of an attack, a baseline percentage distribution of HTTP requests among the different possible user agents, and may then simply block all traffic specifying a particular user agent that is in excess of the baseline percentage for that agent.) Similarly a sudden change in the number of requests without the agent field, or with a bogus agent field, may be indicative of a zombie attack. Occurrence of other regular patterns in the incoming traffic—Zombies tend to send many identical packets repeatedly, at regular intervals. Detection of this sort of repeating pattern may be indicative of an attack.
Other attack detection criteria will be apparent to those skilled in the art. Additional criteria (not necessarily zombie-based) are described in the above-mentioned related applications.
As long as no attack in progress, guard processor 28 typically permits incoming packets to pass through to server 22 , at a packet delivery step 52 . On the other hand, when an attack is believed to be in progress, guard processor 28 filters some or all of the incoming traffic, at a filtering step 54 . For this purpose, the guard processor maintains a record in database 30 of IP source addresses that are known to be legitimate (because of past communications with these source addresses, as described below). Database 30 may also contain a “blacklist” of addresses that are believed to be malicious. Guard processor 28 checks the source address of each incoming packet against the database record, at a source address checking step 56 . If the address appears on the legitimate list, the packet is passed on to server 22 at step 52 . (Additionally or alternatively, if the address appears on the blacklist, the packet may be discarded.)
If the IP source address of the incoming packet is unknown, guard processor 28 tests the address to determine whether it is legitimate or spoofed, at a spoofing check step 58 . Typically, the guard processor initiates a challenge/response routine, by sending a packet (the “challenge”) containing certain information to the IP source address of the incoming packet via interface 29 . The guard processor then checks that the response packet received from the IP source address contains appropriate matching information, at an IP authentication step 60 . Various challenge/response methods that may be used for this purpose are described in the above-mentioned U.S. patent application Ser. No. 10/232,993. If the IP address is found to be bogus, the incoming packet is discarded, and the address may be entered in the blacklist in database 30 , at a packet discard step 62 .
FIG. 3 is a message flow diagram, which shows details of spoofing check step 58 , in accordance with one embodiment of the present invention. In this example, the TCP three-way handshake is used to authenticate the source IP address. The message flow begins when guard processor 28 intercepts a TCP SYN packet sent from an IP source address that does not yet appear in database 30 . The SYN packet has a certain packet sequence number (s#), in accordance with TCP convention. The guard processor sends back a TCP SYN-ACK packet to the IP source address of the SYN packet via interface 29 . The SYN-ACK packet contains an encoded cookie (c#), which is encoded in the sequence number (s#) of the packet. Any suitable method of cookie generation that is known in the art may be used for this purpose and for generating cookies in other embodiments of the present invention. In one embodiment, a hash generator implements a hash function for mapping packet attributes, such as the IP source address and port, to cookies. The hash generator calculates a hash value, which is used as a key for indexing a cookie table comprising a set of random cookies. The random cookie values are replaced after use to prevent an attacker who succeeds in discovering a legitimate cookie value from re-using the cookie.
If guard processor 28 then receives a proper TCP ACK packet back from the same IP source address, identified by the proper sequence number and cookie, the guard processor is able to ascertain that the source address is legitimate, rather than spoofed. (Note, however, that the guard processor still does not know whether the computer at this source address is a zombie or not). Alternative anti-spoofing methods are described in the above-mentioned related applications.
Returning now to FIG. 2 , after guard processor 28 verifies that the IP source address of a given packet is authentic at step 60 , it may go on to test the legitimacy of the higher-level software running on the source computer, at a protocol challenge step 64 . In the present embodiment, it is assumed that guard device 27 is protecting a Web server (as shown in FIG. 1 ), and that the guard processor has intercepted a HTTP request from an unknown source address. Step 64 tests whether the HTTP request was generated by a legitimate browser, complying with all the requirements of HTTP. Based on this test, the guard processor determines whether the source computer is legitimate or a zombie, at a browser legitimation step 66 . An exemplary test of this sort is described below with reference to FIG. 3 .
The test used at step 64 is based on sending a HTTP response, containing a HTML directive (the challenge), back to the IP source address of the incoming HTTP request, and checking the next reply returned from this IP address. For the most part, zombies are driven by relatively simple programs, which may be capable of emulating certain basic aspects of HTTP, but do not implement all the specified functions of HTML (as required, for example, by IETF RFC 1866 and the applicable HTML specification, such as HTML 4.0). Therefore, if the source address returns the reply that is expected in compliance with the protocol, guard processor 28 may conclude that the computer at the IP source address is legitimate, and is not a zombie. In this case, guard processor 28 adds the IP address to the list of legitimate addresses in database 30 , at an address approval step 68 . Packets from this address may now be delivered to server 22 at step 52 . Otherwise, if the computer at the IP source address failed to respond to the challenge or responded incorrectly, the incoming packet is discarded at step 62 , and its IP source address may be added to the blacklist.
FIG. 3 illustrates one type of test that may be used at step 64 . In this example, it is assumed that after the source computer on network 26 establishes its TCP connection with guard device 27 (at step 58 ), it submits a HTTP request for a certain URI on server 22 , for example, GET /index.html. As noted above, the request may also specify other HTTP fields, such as the user agent. The guard processor intercepts this request via interface 29 and returns a response, which redirects the source computer to refresh its browser with a new URI (identified in FIG. 3 as URI′). Requests directed to the URI′ will also be intercepted by the guard processor, but URI′ contains information, such as a cookie, that will enable the guard processor to identify the source of the request. For example, the guard processor may return a response containing the HTML directive: <META HTTP-EQUIV=″Refresh CONTENT=″1; URL=cookie.index.html″>, wherein “cookie” is a unique string generated by the guard processor.
Normally, this response should cause the browser on the source computer to open a new TCP connection with guard processor 28 , and then resubmit its HTTP request to URI′, i.e., to “cookie.index.html”. (To open a new TCP connection, the source computer again sends a SYN packet, receives a SYN-ACK from the guard or the target, and then sends an ACK. These three-way exchanges associated with the HTTP GET URI′ and the final HTTP GET URI are omitted from FIG. 3 for the sake of simplicity.) Upon receiving this new request, the guard processor is able to conclude that it is communicating with a legitimate browser on the source computer, and adds the IP address of the source computer to its approved list in database 30 . The guard processor then redirects the source computer once again to the original URI=index.html. As a result, the source computer will attempt to open yet another TCP connection with server 22 . This time, however, the guard processor will recognize the IP source address of the TCP SYN packet from the source computer as legitimate, and will pass the packet through to server 22 . The server and source computer may then proceed to communicate in the normal fashion.
On the other hand, if the original HTTP request from the source computer was sent by a zombie, rather than by a legitimate browser, the source computer will be unable to parse the HTTP response sent back by guard processor 28 . Therefore, the source computer will not resubmit its request to “cookie.index.html”. Rather, the source computer will, in all likelihood, simply continue submitting further requests to the original URI. Since the guard processor will not have authenticated the IP source address, it will not permit these requests to pass through to server 22 . Furthermore, upon receiving multiple, repeated requests of this sort, the guard processor may conclude that the source of the requests is a zombie, and will then add the IP source address to the blacklist.
Various other methods may be used at step 64 in order to verify that a legitimate browser is operating at a given IP source address. These methods may be based on encoding cookies in other parts of the HTTP response sent by guard processor 28 , or by testing the source computer for compliance with other aspects of the applicable protocols, such as RFC 1866 or RFC 2616. For example, the guard processor may redirect the browser on the source computer by replying to the initial HTTP request with a HTTP redirect response (status code 307 ), redirecting the client browser to URI′, containing the encoded cookie.
Alternatively or additionally, the response sent by the guard processor may test whether the original HTTP request sent by the source computer was submitted in response to instructions of a human operator of the source computer. For example, the response may cause the browser on the source computer to display an image or play a sound, and prompt the human operator to type a corresponding word into the computer. The response causes the source computer to return the word that the user has typed, thus permitting the guard processor to verify the presence of a human user operating the browser on the source computer. A zombie, clearly, will fail this test. Challenge/response routines of this sort, for verifying the presence of a human user on the source computer, are described further in the above-mentioned U.S. patent application Ser. No. 09/929,877.
Although the embodiment described above makes reference particularly to HTTP and its use in conjunction with Web server 22 , the principles of the present invention are generally applicable to authentication of incoming traffic using higher-level protocols of other types. In the context of the present patent application, the term “higher-level protocol” refers to protocols operating above the transport layer (layer 4 ), as defined by the well-known Open Systems Interconnection (OSI) Reference Model. Internet traffic generally uses TCP or UDP as its transport-layer protocol. Higher-level protocols that may operate over TCP or UDP include (but are not limited to) HTTP, FTP, DNS, RTP, POP/SMTP, SNMP, Usenet, Telnet and NFS. These protocols are generally classified as “presentation-layer” protocols, although this is a loose classification, and these protocols are also often referred to as “application-layer” protocols.
In any case, when clients attempt to communicate with a server according to any higher-level protocol such as these, a guard device protecting the server may use a challenge/response technique based on the requirements of the specific protocol in order to authenticate the sources of the communications. For example, the above-mentioned U.S. patent application Ser. No. 10/251,912 describes methods and devices for distinguishing between spoofed and authentic DNS requests. Many other higher-level protocols (in addition to those listed above) are known in the art, and are amenable to authentication by the methods of the present invention.
Furthermore, although the embodiments described above are directed mainly to processing IP packet traffic sent over the Internet, the principles of the present invention are similarly applicable to networks of other types, using other protocol families. It will thus be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art. | A method for authenticating communication traffic includes receiving a first message, sent over a network from a source address, requesting information from a server in accordance with a higher-level protocol. A challenge is sent to the source address in reply to the first message, in accordance with the higher-level protocol. A second message is received from the source address following the challenge, and the legitimacy of the source address is assessed by determining whether the second message contains a correct response to the challenge. | 7 |
FIELD OF THE INVENTION
This invention relates to a continuous wet-laid process for forming a nonwoven structure containing fibers and the dried residue of particulate water insoluble, water-swellable, superabsorbent polymer (SAP), (hereinafter called a composite). The wet-lay process is similar to a paper process. The composite is useful in absorbent hygiene products such as diapers, incontinence pads, sanitary napkins, tampons, in filtration devices, and in wiping materials for mopping up spills of fluids. A wet-laid nonwoven fabric is a fabric comprising fibers which have been deposited from an aqueous suspension onto a moving foraminous support.
BACKGROUND OF THE INVENTION
Fibrous, nonwoven, superabsorbent, polymer-impregnated structures are known. See generally, U.S. Pat. Nos. 5,167,764, 5,607,550, 5,516,585. European Publication No. 437,816 discloses a wet laid process for incorporating superabsorbent which entails forming a gel on mixing of the SAP particles and fibers in a slurry. The amount of SAP contained in the webs taught is up to 60% of the total weight of the web. The particular superabsorbent particles used in the process taught in EP 437,816 yield a web which exhibits a characteristic absorbency under load (AUL). Higher AUL has been achieved for SAP more recently, however the use of these higher AUL SAPS in a continuous large-scale wet lay process presents serious difficulties. Attempting to use a commercial wet lay process in light of the teachings of the state of the art will present serious problems for example if fine particle size SAP (100 micron or less) or SAP particles which are surface crosslinked are attempted. The small particle size (less than 200 micron ) SAP or surface crosslinked SAP or particle range 200 to 850 micron can form a gel and result in a non-uniform web and a web which cannot be dried by practical means.
Alternatives to the gellation problem include EP-A-359615 which discloses a method for the manufacture of a superabsorbent fibrous structure in which a dry solid absorbent is applied directly to a wet-laid web of cellulosic fibers prior to drying the wet web.
EP-A-273075 discloses a high water-absorbency paper made by sheeting a mixture of wood pulp fiber, water-soluble resin and high water-absorbency resin.
Absorbent products such as diapers which include particles of a superabsorbent polymer such as crosslinked sodium polyacrlate disposed between layers of wood pulp are known for example from EP-A-257951.
The use of fibers of water-swellable water-insoluble superabsorbent, polymer is disclosed in U.S. Pat. No. 5,607,550, wherein it is taught that incorporation of superabsorbent, polymers in particulate form in the fiber web have significant disadvantages in many respects. The prior art teaches that superabsorbent, polymer particles are less securely retained and with less uniform dispersion of superabsorbent particles as opposed to the dispersion of the fibers of SAP. It is also taught conventionally that with superabsorbent, polymer particle-impregnated structures, the particles are loosely attached to the fibrous structure of the nonwoven fabric and attrition or loss is evident.
In order to provide sufficient absorbency performance for utilization in state-of-the-art absorbent articles, it has been found that a minimum 0.3 psi AUL of 30 for the SAP is needed and desiredly the percent loading of superabsorbent in a fibrous web needs to be at least about 50% by weight. However, loadings of SAP particles in a fiber structure (such as above about 80% SAP particles on the total weight of the web) have insufficient strength for the wet web to convey through the wet-lay forming process.
Whereas the cost associated with forming fibers of superabsorbent, polymer is inherently higher than that of the particulate SAP, it would be desirable to overcome the aforementioned drawbacks in the use of particles of SAP. Composite structures of fibers impregnated with superabsorbent, polymer particles could greatly reduce the manufacturing cost of end use products such as those aforementioned.
Co-pending U.S. Patent application Ser. Nos. 09/026,002 and 09/025,384 disclose process to make SAP/fiber composites by the wet laid nonwoven method and utilize added salt in the furnish to retard the gellation of the SAP. The presence of salt gives rise to inefficiencies in the process as well as environmental compliance issues. Therefore it would be desirable to eliminate salt addition to the furnish. Accordingly, there is a need for an environmentally friendly process to make SAP/fiber composite on commercial scale wet-lay equipment and at sufficient line speeds to be of commercial economical importance. An improved process for forming such a composite has been found which yields a uniform web which can be dried using conventional drying equipment. The web also exhibits advanced absorbency performance.
SUMMARY OF THE INVENTION
In accordance with the invention there is provided a process to form a nonwoven, wet-laid, superabsorbent, polymer particle-impregnated fibrous structure on a commercial scale wet-forming machine having a head box, a forming section and a drying section, the process comprising
adding SAP to water and within 5 seconds of the SAP water contact, providing agitation of at least 4000 Reynolds units thereby dispersing ungelled SAP particles throughout the fiber furnish,
delivering the furnish to a moving foraminous support, forming a wet laid web containing wetted SAP particles, draining of water from the moving wet web, and conveying the web to the dryer section,
wherein the maximum elapsed time from the point where SAP is mixed with water to the time the web passes into the dryer section is 45 seconds or less.
DETAILED DESCRIPTION OF THE INVENTION
All percentages specified herein are weight percentages. Specifically, the process forms a structure which comprises from 50% to 80% of SAP, and 20% to 50% fibers. The preferred fibers are a combination of wood pulp fibers and cellulose acetate fibers. The aqueous furnish comprises normally available water such as well water, or treated municipal water. Salt addition is obviated. The furnish is passed over a moving foraminous support, such as a Fourdrinier wire, and a wet web structure is formed. Time is critical in the present process. The wet web structure is conveyed to an in-line dryer within the maximum elapsed time of 45 seconds or less from the time the SAP and water are joined. This time can be controlled by the adjusting the speed of the moving foraminous support and dryers conveyors.
The SAP polymer particle-impregnated structure (web) must enter the dryer before substantial gel formation. Substantial gel formation prior to entry of the web into the dryer section was found to cause the web to remain wet after drying, and impossible to process the web on a practical basis. Since it is financially ruinous to observe the failure of a wet laid web by gel formation on a commercial machine, a simple test has been found to assess whether the SAP will generate a failure on the process. The time at which an SAP undergoes substantial gel formation can be separately approximated. The approximate gel time test is assessed in the following manner: 1.0 grams of SAP material is pre weighed. 0.2 L of water are placed in a 250 ml beaker measuring 3 in. by 4 in. Agitation is achieved by a magnetic stirrer at 700 rpm which generates a vortex reaching down to the stirrer. Time zero is marked when the SAP is introduced to the stirring water. The approximate gel time is measured from the point of addition until the vortex closes to a smooth surface. This is an indication of the approximate gel time of the SAP and the critical process parameter of elapsed time expected. The elapsed time on the wet lay forming apparatus from wetting of SAP to entry of the web into the dryer section must not be greater than the time observed using the approximate gel time test.
The wet-laid, superabsorbent, polymer particle-impregnated structure designed for a hygienic articles preferably, on a dry weight basis, comprises about 50% to about 80% water insoluble, water swellable polymer (SAP) and about 20% to about 50% fibers (fibrous portion). The fibrous portion of the web in one preferred embodiment comprises 5% to 50% cellulose acetate fibers and 50% to 95% pulp fibers. More preferably the fibrous portion comprises 10% to 50% cellulose acetate fibers and 50% to 90% wood pulp fibers. Still more preferredly the fibrous portion comprises 10% to 40% cellulose acetate fibers and 60% to 90% wood pulp fibers. Most preferredly, the fibrous portion comprises 5% to 20% cellulose acetate fibers and 80% to 95% wood pulp fibers for absorbent articles for personal hygiene applications.
The SAP/fiber web is produced using an exemplary apparatus known in the art is an inclined wire forming machine. In a typical embodiment of the process the line is started by supplying the head box with fiber slurry and introducing the SAP continuously to the head box while discharging the contents of the head box to the inclined wire. Sap must be wetted with water with agitation of a minimum of 4000 Reynolds units and the agitation must be achieved within 5 seconds of the water impingement to the SAP. Reynolds number calculations are found in Perry's Chemical Engineers Handbook, 6th Ed. 1991.
Preferably agitation of the specified minimum Reynolds number is applied in 4 seconds or less. This agitation can be provided by circulating the slurry within the head box. Agitation outside the head box can be by way of what is referred to in the art as a hootenany. The principle of a hootenany utilizes a fluid stream flow to generate an eductive or negative force which can be utilized to add a second stream. This technique is applied for powder type feeds into a fluid stream.
The rate of SAP supplied to the head box is controlled in relation with the rate of fiber furnish added to the head box to yield the desired SAP/fiber weight ratio. For a machine making webs of 1.7 meters width at a basis weight of 150 gsm, and for a 60 wt. % SAP level in the sheet, the consumption of SAP will typically be about 204±5 lbs./hr.
The basis weight of the web is controlled by the speed of the inclined wire and the solids level in the furnish. The basis weight of the dried composite ranges typically from 100 grams per square meter to about 500 grams per square meter (gsm), preferably 100 to 400 gsm. Webs of 100 to 200 are desirable for disposable diapers.
A preferred embodiment of the process is the use of an inline mixer for SAP and water conveyed to the head box through a hootenany.
The residence of the furnish in the head box is controlled by the volume of the head box and the flow rate of the furnish onto the moving wire. For a line speed of 33 ft./min. and basis weight from 100 to 200 gsm, a volume of 8000 gallons per hour of furnish feed to make a 1.7 meter wide web is sufficient to achieve the critical elapsed time parameter maximum of 45 seconds. In order to increase line speeds, the liquid feeds are increased proportionately.
When using an SAP which is surface crosslinked with the maximum elapsed time may be less than 45 seconds. For example, a SAP having a particle size range of 200 to 850 microns, such as made by the process of U.S. Pat. No. 5,597,873 using Kymene® 736 surface crosslinker at 1.2 wt. %, the approximate gel time test indicates that in 54 seconds the SAP will gel. This SAP can therefore be used in the process of the present invention.
It has been found that the particle size of the SAP impacts the time of substantial gellation. In order to operate a commercial wet lay machine using a SAP having a particle size of less than 200 microns, especially if the SAP has been recovered from a surface crosslinked primary SAP, the elapsed time from wetting to dryer should be less than about 10±3 seconds. Line speed would need to be approximately 66 feet per minute to maintain an elapsed time limit of under 10 seconds±3 seconds for a web of 100 to 200 gsm.
The web is transferred from the inclined wire to a conveyor optionally equipped with vacuum suction ports to further remove processing water. The general process, aside from the critical modifications embodied in the present invention is described in "Manual of Nonwovens" by R. Krcma (4th Edition 1974, Textile Trade Press, Manchester) at pages 222 to 226. In general, the fiber and particles are wet-laid in a process similar to a conventional papermaking process. The fiber and particles in the aqueous suspension are continuously deposited on the moving foraminous support. The wood pulp fibers may need to be refined, but this is not essential in the practice of the invention. It is preferred to mix the superabsorbent polymer particles into the slurry after refining-has been completed.
The furnish can be poured or deposited at a controlled rate onto a substantially horizontal mesh screen, or the furnish may be deposited on an inclined mesh screen traveling upwards through the slurry. An inclined wire is preferred. For best results in utilizing available dryer capacity, the furnish should be deposited on a mesh screen which is at the surface of a suction drum. The mesh size of the screen should be such as to allow easy drainage of water but to retain the solids; the most suitable mesh size will generally be in the range 0.2 to 1.5 mm. The mesh can be of metal wire or synthetic polymer, for example polyester filament. The basis weight of the resulting dried web having no more than 0.5% moisture content is preferably from 100 to 500 g/m 2 (gsm), more preferably from 100 to 400 gsm, and most preferably webs of 150±25 and 250±25 gsm are made and utilized in a multi-layered absorbent component in a disposable diaper.
The process of the present invention enables the use of conventional drying means in-line to the web forming process. The wet web is therefore capable by the process of the present invention to be brought to uniform and substantial dryness using suitable techniques generally employed in papermaking including passage of the web around a heated drum, passage between a series of heated rolls, or on a flat bed, a through air dryer. Such drying means can include one or more than one single means, for example, a rotary/thru air dryer and a heated drum dryer, or an infrared heating source, or hot air blowers, or microwave emitting source, and the like, all which are known and used in wet-laid web drying processes. The most preferred drying method is combination of heated drum and through-air dryers which is readily practiced in the art.
All processing waters except that which is driven off in the dryer exhaust, are captured and recycled to the process; these waters are collected in what is identified as the "white water" tank. Web basis weight is controlled by regulating the concentration of superabosrbent polymer and fiber components in the head box. A premixture of SAP and fiber slurry into a large tank followed by feeding this mixture to the forming line is not possible in the present invention. The headbox is of a size such that the SAP is resident in this container for only a matter of several seconds. The turnover of SAP in the headbox is high enough so that the total time elapsed from wetting of SAP until the formed web reaches the dryer will be less than or equal to 45 seconds. Preferably the elapsed time from wetting to dryer is less than or equal to about 30±3 seconds. Most preferably the lapsed time from wetting of SAP until the formed web reaches the dryer section is less than or equal to 25 seconds.
Absorbency Under Load (AUL) for particulate SAP is defined as follows:
AUL is a measure of the amount of saline (0.9% wt/% NaCl aqueous solution) absorbed by the SAP polymer while a predetermined amount of weight is applied to the polymer gel and indicates the effectiveness of the polymer's absorbency in relation to actual use conditions. Absorbency under load is measured using a plastic petri dish with elevating rods and a 1.241" OD×0.998" ID×1.316" long plexiglass tube with a wire net (100 U.S. mesh) at the bottom of the tube. The particle size of the test samples is controlled between 30 to 50 mesh, (passing through a 30 mesh and retained on a 50 mesh).
A test sample, 0.160±0.01 g is weighed out and recorded as S 1 . The sample is placed in the plastic tube and is spread evenly over the wire net. A specified weight(e.g. a 100 g, 200 g or 300 g weight yielding 0.3 psi, 0.6 psi and 0.9 psi load, respectively) and a disc are placed on the sample. The assembly (polymer sample, tube, disc and weight) is weighed and recorded as W 1 . The assembly is then placed in a petn dish containing 40 ml 0.9% saline aqueous solution. After one hour of absorption, the assembly is removed from petri dish and excess saline blotted from the bottom. The assembly is weighed again and this value recorded as W 2 . Absorbency under load (AUL) is equal to (W 2 -W 1 )/S 1 and is express in g/g.
Absorbency Under Load (AUL/(for web sample)
This test is designed to determine the absorbency under load of a web containing a mixture of superabsorbent polymer and fibrous materials. This is a measure of saline (0.9% wt/% NaCl aqueous) solution absorbed by the web while a predetermined amount of weight is applied to the web and indicates the effectiveness of the web's absorbency in a diaper system under the weight of a baby. Absorbency under load is measured by cutting a 2 in. diameter circular sample with a die cutter. The sample is oven dried for 2 hours and then weighed to ±0.1 grams. Prior to testing the sample is cooled in a controlled environment (70° C., 50% RH). The sample holder is then dried with a hand-held heating blow-dryer to complete dryness. The sample holder has small feet on the bottom to insure a clearance between the bottom of a saline liquid reservoir and the holder. The volume of saline solution to be added to the liquid reservoir is determined by adding a measured amount of saline solution to the reservoir until the liquid level rises to the top of the perforated plate(s) of the sample holder(s). This volume of saline solution is recorded as X. The volume of the saline to be added to the reservoir is X+120 mls. The circular web sample is placed top side down, inside the holder. The total weight of the sample in it's holder is recorded as the dry weight. A weight (providing load of 0.5 psi) is placed on top of the web sample. The reservoir is filled with X+120 mls. of 0.9% saline solution at a temperature of 23±1° C. Simultaneously the sample holder(s) is placed into the solution. After ten minutes of swelling, the sample holder(s) are removed from the reservoir and allowed to drip approximately 60 seconds. The weight is removed. The weight of the wet sample is re-weighed in the sample holder (wet weight). Calculations:
absorbed weight=(total weight of wet sample and holder) minus (total weight of dry sample and holder)
AUL (g/g)=absorbed weight divided by oven dried weight of sample
Materials of Web Construction
The fibers used may be filament or staple or a combination of a minor amount of filament and a major amount of staple, or staple fibers of varying lengths. The essential fibers in the web are cellulose acetate (CA) and wood pulp. Optional man-made fibers can be included but are not critical. Polyolefin fibers, polyester fibers and bicomponent fibers could be included. Preferably, all of the fibers used are CA and Pulp staple fibers, generally of length from 1 to 100 mm. In a preferred embodiment, a minor amount (about 20%-30% of the fibrous portion) is polyester fiber (type 103 sold under the TREVIRA® trademark), and from about 2 to 10% of the fibrous portion is made of bicomponent fibers sold under the type 105 Celbond® trademark of TREVIRA. The staple fibers are preferably of 10 to 50 mm in length. The greater the length, the greater the strength of the wet web structure up to a point where greater fiber length may adversely affect processing of the furnish, material cost, and web uniformity. Cellulose acetate staple is usually available in lengths of 2 to 50 mm. The more preferred lengths for cellulose acetate are from 0.25 to 0.75 inch (8 to 19 mm), and most preferred are lengths of about 0.5 in. (=12 mm). Cellulose acetate staple is commercially available from Celanese Acetate, Charlotte, N.C. The denier per filament (dpf) for the cellulose acetate fiber is not critical. Preferably cellulose acetate having 1.8 dpf and 12 mm length (0.5 inch) is used. Longer lengths could be used but at small denier, fiber entanglement can lead to less uniformity in the web.
Wood pulp fluff of typical length of about 8 mm is used in the wet laid nonvoven industry and is also suitable in the practice of the process. Wood pulp fluff fibers can be obtained from well-known chemical processes such as the kraft and sulfite processes. Suitable starting materials for these processes include hardwood and softwood species, such a alder, pine, douglas fir, spruce and hemlock. Wood pulp fibers can also be obtained from mechanical processes, such as ground wood, refiner mechanical, thermomechanical, chemi-mechanical, and chemi-thermomechanical pulp processes. However, to the extent such processes produce fiber bundles as opposed to individually separated fibers or individual fibers, they are less preferred. However, treating fiber bundles is not within the scope of the present disclosure. Recycled or secondary wood pulp fibers and bleached and unbleached wood pulp fibers can also be used. Details of the production of wood pulp fibers are well-known to those skilled in the art. These fibers are commercially available from sources including Weyerhaeuser Company, Buckeye Cellulose, and Rayonier.
The superabsorbent-polymers in particulate form as specified above generally fall into three classes, namely, starch graft crosslinked copolymers, crosslinked carboxymethylcellulose derivatives, and hydrophilic polyacrylates. Examples of such absorbent polymers are hydrolyzed starch-acrylonitrile graft copolymer, a neutralized starch-acrylic acid graft copolymer, a saponified acrylic acid ester-vinyl acetate copolymer, a hydrolyzed acrylonitrile/carboxylate copolymer or acrylamide copolymer, a partially neutralized self-crosslinking polyacrylic acid, a partially neutralized, lightly crosslinked polyacrylic acid polymer, carboxylated cellulose, a neutralized crosslinked isobutylene-maleic anhydride copolymer, and the like.
The superabsorbent polymer particles need not be but preferably have at least a portion of their surface which is crosslinked. The preferred SAP are surface crosslinked polyacrylic acid polymers as taught in U.S. Pat. Nos. 4,507,438, 4,541,871, 4,666,983, 5,002,986, 5140,076, 5,164,459, 5,229,466, 5,322,896, 5,597,873, and EP 509,708.
The fiber/SAP/solids content of the slurry referred to below, deposited on the foraminous support (wire) is generally in the range 0.1 to 50 g/liter solids content, preferably 0.2 to 20 g/liter, and more preferably 0.2 to 5 g/liter. Depending on the feed rate of furnish on the wire and the speed of the line, a solids content in the area of 0.2 to 2 g/liter can be run and conditions adjusted so that a basis weight of from 100 to 500 gsm can be achieved on typical conventional wet-laying machinery. A portion of the water content of the slurry is drained from the deposited fiber/SAP layer while it is supported on the mesh screen, preferably with the aid of suction applied below the screen. Optional compression rolls can be used but are not essential and may be desired when dryer capacity is limited and particularly when making higher basis weight webs (350 gsm and above). The solids content of the wet-laid web as it is taken off the mesh screen is preferably at least 5% and most preferably at least 10% by weight, and it is generally not more than 30% and usually not more than 20% by weight prior to treatment with water.
The wet-laid nonwoven structure can optionally include dispersed particles such as silica, a zeolite or a mineral clay, such as kaolin or bentonite. Such particles, which preferably are not used at more than 10% by weight of the nonwoven fabric, can be added to the furnish as described in EP-A-437816 or incorporated in the superabsorbent particles as described in WO-A-92/19799.
EXAMPLES
Example 1
Using a commercial wet-lay web former such as available under the Bruderhaus® trademark, the following is made:
Superabsorbent, surface crosslinked SAP with a particle size range of 200 to 850 (Sanwet IM-7200, ex Clariant), was used in this example. The SAP was wetted with the aqueous slurry and within 5 seconds was agitated by the fluid velocities of the stock and white water feeds and baffling inside the headbox adjusted in order to provide a minimum 4000 Reynolds number to be achieved. The aqueous slurry as it left the head box comprised about 2.5 grams per liter of solids, with solids comprising 60% of the SAP particles and 40% of the fiber portion. The fiber portion consisted of 75% CA fiber and 25% of bicomponent fiber (CELLBOND® TYPE 105, ex Trevira). As the SAP was added to the slurry, the combined SAP-slurry was deposited onto the moving inclined wire at a flow rate of 8,000 gallons per hour to form a 1.7 meter wide moving wet web. The web was advanced at the rate of 10 meters/min. and was passed to the dryer zone with an elapsed time of 15-20 seconds from the time of wetting until the time the web passed into the entry point of the dryer zone. The web was uniform in dispersion of SAP and dried uniformly and could be wound up as it emerged from the drying section. The web had a nominal basis weight of 150 gsm. The AUL for the web was 16 g/g, corresponding to AUL per unit SAP of 25 g/g. | A process to form a nonwoven, wet-laid, superabsorbent, polymer particle-impregnated fibrous structure on a commercial scale wet-forming machine having a head box, a forming section and a drying section, including
adding SAP to water under and within 5 seconds of the SAP water contact,
providing agitation of at least 4000 Reynolds units thereby dispersing ungelled SAP particles throughout the fiber furnish,
delivering the furnish to a moving foraminous support, forming a wet laid web containing wetted SAP particles, draining of water from the moving wet web, and conveying the web to the dryer section,
wherein the maximum elapsed time from the point where SAP is mixed with water to the time the web passes into the dryer section is less than 45 seconds. | 3 |
FIELD OF THE INVENTION
This invention relates generally to injection molding of plastics and more particularly to an injection molded plastic component having a fuel vapor barrier layer and a method of making it.
BACKGROUND OF THE INVENTION
Increasingly strict governmental regulations regarding the emission and escape to the atmosphere of hydrocarbon vapors are being continually promulgated. In various fuel systems, plastic fuel tanks are utilized because they are relatively inexpensive to produce, resistant to corrosion and lightweight. To reduce the escape to the atmosphere of hydrocarbon vapors from these fuel tanks a fuel vapor barrier layer is incorporated into the plastic fuel tank to inhibit and reduce the permeation of fuel vapors therethrough.
While the vapor barrier layer is generally effective at inhibiting fuel vapor permeation through the fuel tank walls themselves, various openings are formed through the fuel tanks to provide access to its interior. One hole preferably has a fill pipe attached thereto to permit fuel to be added to the fuel tank. One or more additional holes may be provided to receive a fuel pump, fuel vapor vent valve and other components desired to be disposed within the fuel tank. Closures for these openings have been formed from solely the structural material of the fuel tank, for example, high density polyethylene. Therefore, these closures provide less resistance to the permeation of hydrocarbon fuel vapors therethrough and undesirably increase the hydrocarbon emissions from the fuel tank. Providing a fuel vapor barrier layer on the closures is difficult and expensive because the materials typically used to form the barrier layer are not readily bondable or weldable to the structural material. Further, coextruding and thereafter molding a multiple layered polymeric article, as is typically done for multiple layer plastic fuel tanks, is difficult to control and relatively expensive.
SUMMARY OF THE INVENTION
An injection molded component having at least one structural layer of material and at least one fuel vapor barrier layer carried by the structural layer, and a method of making it utilizing separately formed structural and fuel vapor barrier layers. The vapor barrier layer may be trapped between two other interconnected layers, or may be bonded to a structural layer by an adhesive. In one form, an adhesive polymeric layer is separately injection molded. A fuel vapor barrier layer is then molded on one side of the adhesive layer and the adhesive layer is heated to activate the adhesive and bond it to the fuel vapor barrier layer. Thereafter, a structural layer of material, such as a layer of high density polyethylene (HDPE), is molded onto the other side of the adhesive layer and the adhesive layer is heated to activate the adhesive and bond the adhesive and structural layers together. In this manner, both the HDPE layer and the vapor barrier layer are bonded to the adhesive layer to provide a component having structural integrity due to the HDPE layer and a high resistance to the permeation of fuel vapor therethrough due to the fuel vapor barrier layer. Desirably, the heat generated during the steps of molding both the vapor barrier layer and the structural layer onto the adhesive layer is sufficient to activate the adhesive and bond the layers together.
In another form, material used to provide the structural integrity is blended with a material used as an adhesive for the component. This structural and adhesive material blend is injection molded into its desired shape. Thereafter, a layer of a suitable fuel vapor barrier material is molded onto the preformed structural and adhesive blend layer which is heated to activate the adhesive material within the blend layer to bond the vapor barrier layer to the blend layer. Thus, according to this aspect of the invention, the component has two layers of material providing for structural integrity of the component and the desired resistance to permeation of fuel vapor therethrough. Preferably, the heat from the molding of the vapor barrier layer onto the blend layer is sufficient to activate the adhesive and bond the layers together.
In accordance with yet another aspect of the present invention, an outer structural layer is injection molded to its desired final shape. A layer of fuel vapor barrier material is molded onto one side of the outer structural layer and an inner structural layer is molded over the fuel vapor barrier layer to encapsulate the fuel vapor barrier layer between the inner and outer structural layers. A mechanical lock such as undercut or dovetail grooves may be used to join the inner and outer structural layers together and to maintain the relative location and orientation of each of the layers. Thus, in this embodiment the component has three separate layers with a fuel vapor barrier layer sandwiched between two structural layers.
In another form, the component is comprised of an insert having a vapor barrier layer and a structural and/or adhesive material with a structural layer molded onto and bonded to the insert. The insert may be formed as a multiple layer extrusion or it may be molded.
Desirably, in each embodiment the injection molded component has at least one layer providing structural integrity for the component and at least one layer which reduces or inhibits the permeation of hydrocarbon fuel vapors through the component. Accordingly, such an injection molded component may be used as a closure for an opening through a fuel tank or to define a body of a component attached to the fuel tank such as for a fuel vapor vent valve, fill nipple weldment and the like. Desirably, the structural layers of the injection molded component facilitate direct attachment of the component to a plastic fuel tank, such as by ultrasonic or other welding methods. Further, the injection molded component could be connected and sealed to a metal fuel tank as well such as by metal fasteners and a gasket or an adhesive, for example.
Objects, features and advantages of this invention include providing injection molded components with a fuel vapor barrier layer to reduce permeation of hydrocarbons through the component which facilitates sealing engagement and attachment to another object such as a fuel tank, is weldable to typical plastic fuel tanks, permits individual layers of material to be separately molded, can be formed without an adhesive layer, is of relatively simple design and economical manufacture and assembly, is durable and has a long, useful life in service.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of this invention will be apparent from the following detailed description of the preferred embodiments and best mode, appended claims and accompanying drawings in which:
FIG. 1 is a perspective view of a fuel tank having an injection molded component according to a first embodiment of the present invention;
FIG. 2 is a fragmentary cross-sectional view of the injection molded component according to the first embodiment of the present invention;
FIG. 3 is a fragmentary cross-sectional view of an injection molded component according to a second embodiment of the present invention;
FIG. 4 is a fragmentary cross-sectional view of an injection molded component according to a third embodiment of the present invention; and
FIG. 5 is a fragmentary cross-sectional view of a molded component according to a fourth embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring in more detail to the drawings, FIGS. 1 and 2 illustrate an injection molded component 10 defining a closure for a fuel tank 12 and having a fuel vapor barrier layer 14 formed of a material which inhibits the permeation of hydrocarbon fuel vapors attached by an intermediate adhesive layer 16 to a structural layer 18 , preferably of high density polyethylene (HDPE). Desirably, each of the layers 14 , 16 , 18 of material are molded in separate steps. So formed, the component 10 has structural integrity, due mainly to the HDPE or structural layer 18 , and is resistant to the permeation of hydrocarbon fuel vapors therethrough, due mainly to the fuel vapor barrier layer 14 . Desirably, the component 10 may be used as a closure for an opening 15 of a fuel tank 12 having one or more nipples 17 for attachment of fuel or vent lines and electrical connectors, as needed. The component may also be, by way of example and not limitation, a weldment or other portion of various components adapted for use with the fuel tank 12 such as a fuel vapor vent valve or a fill pipe nipple weldment 19 connectable to a fill pipe 21 through which fuel is added to the fuel tank 12 .
In the preferred method of forming the injection molded component 10 the adhesive layer 16 is first injection molded independently of the other layers 14 , 18 to its desired final shape having, generally, two opposed sides 20 , 22 . In general, the material of the fuel vapor barrier layer 14 cannot be readily bonded to the material of the structural or HDPE layer 18 . Therefore, the adhesive layer 16 is required between them to bond them together. The adhesive layer 14 may be formed of any suitable adhesive polymer, such as ADMER adhesive commercially available from Mitsui Chemicals. Of course, this polymeric adhesive is merely representative of a wide range of materials which may be injection molded and suitable for use as the adhesive layer 16 of the injection molded component 10 . The adhesive layer 16 may be substantially any material which has an adhesive quality or component that suitably bonds together the structural and vapor barrier layers 14 , 18 in the molding process as described. Since the adhesive layer 16 is provided merely to bond the fuel vapor barrier layer 14 to the structural layer 18 of HDPE, it can usually be made very thin to reduce cost. In a representative closure for a fuel tank 12 , the adhesive layer 16 may be on the order of between 0.001 mm thick to 1.5 mm thick in the preferred embodiment.
The second step of forming the injection molded component preferably comprises injection molding the vapor barrier layer 14 onto one side 20 of the adhesive layer 16 and heating the adhesive layer to activate it. This may be accomplished, for example, by placing the already molded adhesive layer 16 into a mold and injecting the material for the vapor barrier layer 14 into the same mold and onto the adhesive layer 16 . Desirably, the heated, molten material of the fuel vapor barrier layer 14 and the mold, if heated, transfers heat to the adhesive layer 16 to activate the adhesive and bond the adhesive material to the fuel vapor barrier material. Such bonding includes without limitation, physical or mechanical bonding and/or chemical bonding between the layers. Generally, to activate the adhesive layer formed of an ADMER adhesive, it should be heated to a temperature of between 400° F. to 600° F., and desirably between 450° F. to 550° F. In general, the higher the temperature the better the activation of the adhesive material.
The fuel vapor barrier layer 14 is formed of a material resistant to the permeation of hydrocarbon fuel vapors therethrough. Some suitable materials for this layer 14 are ethylene vinyl alcohol (EVOH) and liquid crystal polymers. The materials suitable for this layer are, in general, somewhat expensive. Therefore, the fuel vapor barrier layer is preferably formed very thin and on the order of between 0.001 mm to 2.0 mm thick. Desirably, when the injection molded component 10 is used as a closure for a fuel tank opening, the fuel vapor barrier layer 14 is continuous, uninterrupted and spans the entire opening of the fuel tank 12 to reduce the emission of hydrocarbon fuel vapors from the fuel tank 12 .
The third step in forming the injection molded component 10 is to injection mold the structural layer 18 onto the opposite side 22 of the adhesive layer 16 as the vapor barrier layer 14 . This may be accomplished, for example, by disposing the bonded together adhesive layer and fuel vapor barrier layer into a mold and injecting the molten HDPE for the structural layer 18 into that mold and onto the exposed side 22 of the adhesive layer 16 . Again, the heat of the molten HDPE is preferably used to activate the adhesive material so that the HDPE is bonded to the adhesive layer 16 . The HDPE is relatively inexpensive, creates the structural integrity of the component and hence, is preferably somewhat thicker than the adhesive layer 16 and fuel vapor barrier layer 14 . For example, the structural layer 18 may be between 0.5 mm and 10.0 mm thick. This range is merely illustrative, and is not intended as a limitation of the invention. Desirably, the outer layer of a plastic fuel tank 12 with which the injection molded component may be used is preferably also formed of HDPE to facilitate bonding and sealing the injection molded component 10 to the fuel tank 12 such as by ultrasonic or other welding methods. Other materials may be used for the structural layer 18 as desired to provide the needed structural integrity of the component 10 and to facilitate bonding to both the adhesive layer 16 and to the fuel tank 12 or other object with which it is used.
As shown in FIG. 3, a molded component 30 according to a second embodiment of the invention has a fuel vapor barrier layer 32 which is overmolded and sandwiched between mechanically interlocked inner and outer layers 34 , 36 , respectively of HDPE. To form this injection molded component 30 , preferably the outer HDPE layer 36 is injection molded as a first step. The outer HDPE layer 36 is molded to its desired final shape and includes at least a pair of outwardly projecting fingers 38 having inclined inner surfaces 40 defining an undercut groove or dovetail slot 42 between them. Next, the fuel vapor barrier layer 32 is molded onto an inside surface 44 of the outer HDPE layer 36 . Finally, the inner HDPE layer 34 is molded onto a temporarily exposed surface 46 of the fuel vapor barrier layer 32 SO that the fuel vapor barrier layer 32 is preferably totally encapsulated by the inner and outer HDPE layers 34 , 36 . The inner HDPE layer 34 is formed around the fuel vapor barrier layer 32 and the adjacent portions of the outer HDPE layer 36 . The inner HDPE layer 34 fills in the dovetail slot 42 of the outer layer 36 and assumes the shape thereof to provide a dovetail mechanical interlock between the inner and outer HDPE layers 34 , 36 to prevent their separation. A mechanical interlock is required because in the second embodiment there is no adhesive layer and the material of the fuel vapor barrier layer 32 does not readily bond or adhere to the HDPE of the inner and outer layers 34 , 36 . Accordingly, the mechanical interlock is preferably provided at several spaced apart locations about the injection molded component 30 to secure and maintain the inner and outer HDPE layers 34 , 36 together with the fuel vapor barrier layer 32 trapped between them.
As shown in FIG. 4, a molded component 50 according to a third embodiment of the invention has a structural and adhesive blend layer 52 with a fuel vapor barrier layer 54 bonded directly thereto. The blend layer 52 comprises a mixture of a structural polymeric material and an adhesive material. The structural polymeric material may be HDPE, as discussed with regard to the previous embodiments of the injection molded component. The adhesive material may similarly be an ADMER or other polymeric adhesive as previously described. The blend layer 52 may be of any suitable composition so long as it has sufficient structural integrity for the intended use of the component 50 , due mainly to its HDPE content, and sufficient adhesive qualities, due mainly to its adhesive content, to permit it to bond with the fuel vapor barrier layer 54 .
To form this component, the mixture of the HDPE and adhesive material is preferably first molded to its desired final shape. Thereafter, the fuel vapor barrier layer 54 is molded onto the HDPE and adhesive blend layer 52 . Preferably, the heat from the step of molding the fuel vapor barrier layer 54 onto the blend layer 52 activates the adhesive in the blend layer 52 to bond the fuel vapor barrier layer 54 onto the blend layer 52 . A currently preferred composition of the blend layer 52 comprises about 50 percent HDPE and 50 percent adhesive. The structural material may comprise between 10% and 99%, by weight, of the blend layer 52 .
As shown in FIG. 5, a molded component 60 according to a fourth embodiment of the invention has a multi-layer film insert 62 with a structural layer 64 bonded directly to the insert 62 . The multi-layer film insert 62 preferably comprises a multiple layer co-extrusion having layers of structural material, adhesive material and a vapor barrier material. The structural material may be HDPE, as discussed with regard to the previous embodiments of the injection molded component. The adhesive material may similarly be an ADMER or other adhesive including polymeric adhesives as previously described. The vapor barrier layer material may be EVOH or other suitable material, such as liquid crystal polymers. The multi-layer film insert 62 may be of any suitable composition so long as the fuel vapor barrier layer material is substantially continuous throughout the insert 62 to reduce or eliminate leakage of fuel vapor through the component 60 . Desirably, the substantially continuous fuel vapor barrier layer could be at least 0.001 mm thick. In addition to multiple layer extrusion, the insert 62 may be formed by other methods including injection molding.
To form this component, the multi-layer film insert 62 is preferably first molded or otherwise formed to its desired shape. Thereafter, the structural HDPE layer is molded onto the insert 62 . Preferably, the heat from the molding of the structural layer 64 onto the insert 62 activates the adhesive in the insert 62 and preferably also causes some melting of the HDPE in the insert 62 to bond the structural layer 64 to the insert 62 . The insert 62 may be formed by multiple layer extrusion methods, or it may be injection molded or otherwise formed.
Accordingly, an injection molded component 10 , 20 , 50 , 60 embodying the invention has at least one layer 18 , 34 or 36 , 52 , 64 providing primarily the structural integrity of the component and at least one fuel vapor barrier layer 14 , 32 , 54 , 62 carried by the structural layer to reduce hydrocarbon permeation through the component. The injection molded component 10 , 30 , 50 , 60 may also utilize an adhesive to bond the fuel vapor barrier layer 14 , 54 , 62 to the structural layer 18 , 52 , 64 . Desirably, the structural layer 18 , 34 and 36 , 52 , 64 may be readily attached to an object such as a fuel tank 12 and the fuel vapor barrier layer 14 , 32 , 54 , 62 increases the resistance to permeation of hydrocarbon fuel vapors through the component 10 , 30 , 50 , 60 . The structural layer 18 , 34 , 36 , 52 , 64 is preferably formed at least in part of HDPE and may be readily bonded to a polymeric fuel tank 12 itself having structural layers of HDPE. Additionally, the injection molded component 10 , 30 , 50 , 60 may be attached to other objects, including steel fuel tanks by mechanical connectors, such as bolts or screws with a gasket between the component and the steel tank, or by an adhesive which bonds the component to the tank.
The process of forming the injection molded component 10 , 30 , 50 , 60 can be substantially automated. In one currently contemplated form, a plurality of molds may be mounted on a carrousel and rotated from one workstation to another with each workstation injection molding a different material into the molds. Movement of the molds can be timed to permit a sufficient cooling and set-up period for each layer of the injection molded component. Additionally, to facilitate automation, the layers may be formed in an order other than that described above. Those skilled in the art will recognize still other modifications to the present invention without departing from the spirit and scope of the invention as defined by the following claims. | An injection molded component having at least one structural layer of material and at least one fuel vapor barrier layer carried by the structural layer, and a method of making it utilizing separately injection molded structural and fuel vapor barrier layers. The vapor barrier layer may be trapped between two other interconnected layers, or may be bonded to a structural layer by an adhesive. In one form, a fuel vapor barrier layer and a structural layer are separately molded onto a preformed adhesive layer. Desirably, the heat generated during the steps of molding both the vapor barrier layer and the structural layer onto the adhesive layer is sufficient to activate the adhesive and bond the layers together. In another form, a fuel vapor barrier layer is bonded to a layer comprised of a blend of structural and adhesive materials. In yet another form, a fuel vapor barrier layer is disposed and captured between two interconnected structural layers. | 1 |
TECHNICAL FIELD
This invention relates to support for objects such as a mailbox.
BACKGROUND ART
Mailbox supports are known in the art and have developed in many different directions. Of relevance to the present invention are mailbox supports with particular ground attachment mechanisms, and mailbox supports which protect the mailbox from damage due to accidental collision.
Mailbox supports with particular ground attachment means are shown by U.S. Pat. Nos. 3,011,597 and 3,011,598 to Galloway et al., and by U.S. Pat. No. 2,738,941 to Laurich et al. The patents to Galloway et al. show a ground attachment means which includes a pipe with an auger on one end and a vane structure on the upper end of the ground attachment device. The pipe extends above the ground so as to be received by another pipe to which the mailbox is attached. The ground attachment device described in the Galloway et al. patents suffers from the disadvantage that when the mailbox support pipe is removed, a large portion of the ground attachment device extends above the level of the ground. In the mailbox support shown by Laurich et al the ground attachment device comprises a pipe with vanes on it which is inserted into the ground so that a large part of the ground attachment device extends above the ground for receiving the mailbox support pipe.
Devices for absorbing the shock of a collision with the mailbox are shown in the U.S. Pat. Nos. 2,550,338 to Dunagan and 4,213,560 to Hall. These devices include platforms which are attached to the mailbox support pipe via a bolt so that the mailbox platform rotates about the axis of the bolt.
STATEMENT OF THE INVENTION
In the mailbox support of the invention the ground base unit is a large sturdy pipe which is inserted into the ground so that the top of the pipe is essentially flush with the ground level. The large sturdy pipe has two annular washers welded therein with aligned central holes, which are adapted to receive a pipe which supports the mailbox. The pipe supporting the mailbox fits inside of the ground base unit and may have a collar which is adjustable along the pipe support for cooperation with the top of the ground base unit for determining the height of the mailbox above the ground. When it is desired to temporarily move the mailbox, one need merely pull the mailbox support pipe out of the ground base unit, and when it is desired to remount the mailbox, the pipe may merely be reinserted into the ground base unit. Also, if the support pipe is damaged, it is easily replaced. The ground base unit may also have a simple pipe clamp welded to the top thereof to secure the mailbox pipe to the ground base unit. In this case the clamp must be released before the support pipe is removed.
Also the ground base unit may have dirt auger blades to facilitate insertion of the ground base unit into the ground. When it is necessary to remove the ground base unit, the annular washers may be grasped by a hook and the base unit pulled out of the ground by means of a jack or other element.
The mailbox platform of the invention is attached to the pipe supporting the mailbox in a simple and inexpensive manner. A pipe coupling is welded to the mailbox base plate and then is secured onto a threaded upper portion of the support pipe. A pipe clamp is welded to the lower part of the pipe coupling so that it may grasp the mailbox support pipe. By adjusting the diameter of the pipe clamp, the resistance to rotation of the mailbox may be varied. Additionally, a second pipe clamp is located on the mailbox support pipe below the mailbox and is attached to the first pipe clamp by means of springs. The cooperation of the spring's attraction and the friction between the first pipe clamp and the mailbox support pipe provide a simple and efficient mounting means which protects the mailbox against damage due to accidental collision.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an overall view of the inventive mailbox support including a cross section of the ground base unit.
FIG. 2 shows a cross section taken along line 2--2 of FIG. 1.
FIG. 3 shows a cross section taken along line 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
The mailbox support unit of the invention is shown generally in FIG. 1. A ground base unit 2 is shown buried in the ground and a support pipe 4 is shown being supported by the ground base unit. The support pipe 4 supports a mailbox 6.
The ground base unit 2 is constructed of a very sturdy large diameter pipe 8. Located on the bottom of the pipe are dirt auger blades 10 to enable the ground base unit to be turned into the ground. Since the diameter of the auger blades is less than that of the pipe 8, the ground base unit may be removed without having to rotate the pipe 8. Welded to the interior of the pipe 8 is a first annular washer 12, for supporting a lower end of pipe 4. Welded to the upper end of the pipe 8 is a second annular washer 14 for supporting an upper portion of the pipe 4. The washers 12 and 14 are of sturdy construction and have the holes aligned so that the support pipe 4 may be freely inserted into the ground base unit. The washers provide an additional function in that when the ground base unit is to be removed from the ground, one may easily grasp the ground base unit by using a hook to engage one of the annular washers. A chain with a hook on it is lowered into the ground base unit and the hook is engaged with one of the annular washers, the ground base unit is then raised out of the ground easily.
The ground base unit may be installed in the ground in any known manner. One technique, particularly adapted to the inventive apparatus is to insert the support post into the base unit and work the base unit into the ground.
The height of the support pipe 4 above the ground level is maintained by the position of a locking collar 16 along the pipe 4. The locking collar 16 is an annular collar with a set screw 18 which secures it to the pipe 4. The function of the locking collar 16 is to carry the weight of the support pipe 4 and the mailbox 6. When it is desired to change the height of the mailbox above the ground, the position of the locking collar need merely be adjusted along the pipe 4. If it is desired to remove the mailbox 6 and support pipe 4, as for example, to temporarily store the mailbox or to remove the mailbox due a wide load on the road, one need merely remove the support pipe 4 from the ground base unit while leaving the locking collar 16 secured to the support pipe 4. When the support pipe 4 is reinserted into the ground base unit, the previous level of the mailbox 6 will be maintained without adjustment.
The mailbox 16 is attached to the support pipe 4 by way of a mechanism which allows the mailbox to rotate with respect to the support pipe so that if the mailbox is accidentally hit, it will rotate to avoid damage to the mailbox. A pipe coupling 20 is welded at one end to a base plate 22 of the mailbox. The pipe coupling is then screwed onto a threaded end of the support pipe 4 so that the pipe coupling is supported by the support pipe 4 and yet freely rotates with respect to the support pipe. A first pipe clamp 24 has a semicircular base portion 26 and a U-shaped bolt 28. The semicircular base 26 is welded to the lower portion of the pipe coupling 20. The pipe 4 is then clamped between the U-shaped bolt 28 and the base 26 by tightening the nuts 30. The resistance to rotation of the mailbox 6 with respect to the support pipe 4 may be adjusted by adjusting the clamping pressure of the clamp 24. The mailbox is returned to its original position after rotation by means of springs 32 which extend between the first pipe clamp 24 and a second pipe clamp 34. The second pipe clamp 34 is securely clamped to the support pipe 4 and the springs are attached to the ends of the U-shaped bolts of the respective pipe clamps. When the mailbox 6 is rotated with respect to the support pipe 4, the springs are extended and the restoring force of the springs tends to return the mailbox 6 to its original position with respect to the support pipe 4.
A third pipe clamp 36 may be attached, for example by welding, to the second annular washer of the ground base unit between the second annular washer and the locking collar 16. This pipe clamp 36 secures the support pipe 4 to the ground base unit 2 but allows for easy removal of the support pipe 4 by merely loosening the nuts on the pipe clamp. This arrangement is advantageous since when the support pipe 4 is removed pipe clamp 36, sits at ground level with 1 inch of loose dirt beveled out around base unit, thus effectively providing a ground base unit which is level with the surface of the ground.
There has been shown a novel mailbox support arrangement which is easy to construct and is sturdy and provides the advantage of being easily removable. The inventive support system is flexible since the ground base unit may be easily removed and reinserted at another place in the ground. Also the support pipe 4 may be removed and reinserted with great facility.
In a working embodiment of the invention, the pipe 8 is a 21/2' section of 4" well casing, the washers are 4" in diameter and 1/4" thick, and the support pipe 4 is a 5'71/2" section of 11/2" well pipe.
The foregoing description is only illustrative of the principles of the invention. Numerous modifications may be made, such as by using the invention to support a plurality of objects, or by using non-circular pipes, and any such modification is considered to be within the scope of the invention. | A support unit comprises a ground base unit made of a sturdy pipe having annular washers. The holes in the washers are aligned and adapted to receive a support pipe which extends above the ground base unit for supporting an object such as a mailbox. The object is rotatably attached to the support pipe with elastic elements which return the object to a predetermined orientation after displacement. Also, if the support pipe is damaged, it is easily replaced. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a shutter for closing over a window, door or other opening of a building, for protecting the window, door or opening during extreme temperature conditions, as can occur during fires, in particular bushfires. The invention has been developed particularly in relation to the protection of windows and it will therefore be convenient to describe the invention in that context. However, it will be appreciated that the invention has wider application to doors or other openings, such as chimneys, flues or air vents.
BACKGROUND OF THE INVENTION
[0002] Windows, doors or other openings in buildings form parts of the building structure which can fail during extreme temperature conditions and which thereafter allow entry into the building of flames and embers, and of oxygen which fuel the flames and embers. Once a fire is established within a building, it is difficult to save the building from complete destruction. Accordingly, it is recognised that protection of windows, doors and other openings in a building is important in order to protect buildings against destruction by fire.
[0003] Windows can be protected by shutters which typically are positioned to form a cover over the external side of the window. Shutters exist already to close over a window and certain shutters have been developed for protection of windows in bushfire conditions. However, shutters of which the applicant is aware typically are aluminium roller shutters and a disadvantage with these shutters is that the melting temperature of aluminium can be lower than the temperature to which the shutter is exposed during a bushfire, so that the aluminium shutter could melt in such extreme temperature conditions. For that reason, recent amendments in Australia to building standards require shutters used for protection in bushfire conditions to continue to operate in a protective manner in temperatures exceeding the melting point of aluminium, i.e. in temperatures beyond 700° C.
[0004] Some existing shutters have been constructed in steel, which has a higher melting temperature than aluminium and so does not suffer the same drawbacks as aluminium. However, these shutters do not prevent transmission of radiant heat from the external or fire side of the shutter to the internal or non-fireside, and because of that radiant heat transmission, it is often the case that the window frame or the glass of the window fails even though the shutter is in a position covering the window. These forms of shutters also have sealing issues and therefore can leave gaps between the shutter and the surrounds of the window and this allows ingress of embers and oxygen.
[0005] There are also flame and smoke control ‘curtain’ type products, typically used in indoor environments to prevent the spread of fire from one area of a building to another. These products however have limited benefit when applied externally over windows or doors, as they can be deflected or shifted by wind, or if hit by flying embers and other debris for example, causing the glass of the window to break or allowing ember and heat access to the frame of the window or door. Such curtain type products are also not primarily designed for deflecting the heat, so that they can allow the cavity between the curtain and the window or door to get excessively hot and thus cause the window glass or window or door frame to fail.
[0006] Some curtain fabrics exist that do have fire retardant or heat reflective properties, but these fabrics are not necessarily capable of long term external use. In addition, they can also present difficulties for mounting, so that prohibitively expensive and difficult mounting arrangements are required.
[0007] Accordingly, applicant is not aware of a shutter which operates successfully under extreme temperature conditions as can occur during some extreme bushfire events. The applicant has therefore developed a new and unique shutter which aims to overcome or at least alleviate some of the disadvantages with shutters of the prior art.
SUMMARY OF THE INVENTION
[0008] According to the present invention there is provided a shutter comprising:
an outer sheet of generally square or rectangular shape, a non-combustible insulating panel of generally the same shape as the outer sheet, and a frame, the panel being positioned between the outer sheet and the frame so that the outer sheet overlies a first broad face of the panel and the frame is attached adjacent to a second broad face of the panel which is opposite the first face, the outer sheet having a melting point of greater than or equal to about 840° C., the panel being operable to retard heat transmission from the first face thereof adjacent to the outer sheet to the second face opposite the first face, so that when the first face is exposed to a temperature of 730° C. for a period of 15 minutes, the temperature at the second face does not exceed 250° C., each of the outer sheet and the panel being secured to the frame and the frame being substantially resistant to distortion up to a temperature of about 250° C.
[0015] A shutter of the above kind advantageously can protect a window, door or other opening from both direct flame and from radiant heat, thereby increasing the likelihood of the window, door or other opening surviving extreme temperature conditions. Moreover, the shutter can limit the progression of heat through the window, door or other opening, so that occupants of a building which is subject to an extreme temperature condition, for example a bushfire, can be subject to reduced temperature within the building than would otherwise be the case if the shutter was not fitted to the window, door or other opening. Still further, a shutter according to the invention can be made to have a aesthetically pleasing appearance despite its required construction, which is important given that the shutter is an external fitting which is on view at all times.
[0016] The outer sheet of a shutter according to the invention can be of any suitable material, although a metal outer sheet is considered at this stage to be most appropriate, in particular a steel sheet. Testing to date has employed successfully a 0.5 mm “Colourbond” steel sheet.
[0017] Other materials suitable for adoption for the outer sheet could be employed subject to satisfying the requirement of providing a resistance to melting up to 840° C. Such materials could include metals or fabrics having suitable fire resistance. In the testing to date, a 0.5 mm “Colourbond” steel sheet has provided a non-combustible layer which has resisted melting at temperatures of up to 840° C. Advantageously, such a steel sheet has also provided a suitable barrier against penetration of flame and oxygen to the internal side of the shutter. In addition, that material also is cost effective compared to other materials that could be employed.
[0018] The non-combustible insulating panel can also be manufactured from any suitable material, but in testing to date, a suitable panel has been found to comprise a 13 mm thick plasterboard which is supplied by Lafarge Plasterboard Ltd under the product name “Firestop”. However, it is envisaged that various other materials could satisfy the requirements of the insulating panel of the invention, for example fibrous materials or foam materials, and it is expected that panel thicknesses of between 10 to 16 mm could be employed. Panels of greater or lesser thickness could be employed, but greater thickness panels could increase the bulk of the shutter beyond acceptable levels, while panels of reduced thickness could require more expensive materials that increase the cost of the shutter prohibitively.
[0019] The outer sheet overlies the insulating panel and each of the outer sheet and the insulating panel are attached to or supported by the frame. In some forms of the invention, the outer sheet and the insulating panel can be fixed together and in one arrangement, an adhesive is employed for that purpose. In some forms of the invention, the adhesive can be selected to fail at a certain upper temperature, with the outer sheet then being supported by the frame when adhesive failure takes place. The benefit of selecting an adhesive which will fail at a particular temperature is to allow expansion of the outer sheet during an extreme temperature event. By this mechanism, the adhesive fails which then allows the outer sheet to expand under the extreme temperature, but the outer sheet is maintained in position, albeit less precisely, by the frame. Thus, while allowance is made for some shifting or movement of the outer sheet, that movement is not sufficient to expose the insulating panel to direct flame, and the outer sheet thus continues to perform the function of providing a barrier against flame and oxygen penetration through the shutter. Accordingly, while the aesthetic appearance of the shutter might deteriorate upon failure of the adhesive, the structural integrity of the shutter remains intact and the shutter continues to form an effective barrier and temperature retarder, protecting the window, door or opening over which the shutter has been placed.
[0020] Many suitable adhesives are likely to be available which meet the requirements for fixing the outer sheet and panel in the shutter and for failing at a selected temperature if required. In testing conducted to date, a construction adhesive, Selleys Silicone 401 industrial engineering adhesive sealer, has been successfully employed, having a 205° C. failure temperature.
[0021] Screws can be employed for various fastening requirements. For example, screws can be employed for fastening the outer sheet and the panel to the frame, whereby the screws extend through the outer sheet and the panel and into engagement with the frame. However, it is preferred to minimise the number of screws used because during an extreme temperature event such as a bushfire, heat can be conducted through a screw which projects from the external side of the shutter through to the internal side of the shutter. This conduction can raise the temperature to which the window is exposed and thus excessive conduction can detract from the performance of the shutter and potentially lead to window failure. Additionally, where the screws are fixed to the frame, conduction through the screws can result in heating of the frame and excessive heating can distort the frame and again, detract from the performance of the shutter. Accordingly, by minimising the number of screws which are employed, heat transmission of this kind is minimised and the likelihood of window failure or of frame distortion occurring is likewise minimised.
[0022] For further fixing of the outer sheet and the panel, the frame can include or define a lip or flange, or a channel, within which edge regions of the outer sheet can be captured or located. In this arrangement, edge regions of the outer sheet can be adhesively fixed to the lip, flange or channel, or fixed by suitable fasteners, such as rivets, or they can simply be positioned within the lip, flange or channel. The panel can also be adhesively fixed to the frame, or it can be fixed to the frame by suitable fasteners, or both. The panel can also be positioned within the lip, flange or channel in the same manner as the outer sheet. The lip, flange or channel can extend completely or partially about the periphery of the outer sheet and the panel.
[0023] The frame can be of any suitable shape, construction and material. Testing to date has been conducted with a steel frame, partly of square hollow section (SHS), with dimensions 20×20×2.5 mm. However, it is clearly possible that alternative sections could be used, such as rectangular hollow section (RHS), or right-angle section.
[0024] The frame can have a generally rectangular or square configuration and be located about the periphery or edge regions of the insulating panel, on the opposite side to the outer sheet. However, the frame could be positioned inboard of the edges, or it could extend diagonally across the second face of the panel from each upper corner of the panel to an opposite lower corner. Other frame configurations are possible.
[0025] The frame can thus consist of a portion that is positioned adjacent to the second face of the panel and a lip, flange or channel portion that extends about the edges of the panel and the outer sheet to capture or confine the edges.
[0026] As indicated above, the frame is required to be substantially resistant to distortion up to a temperature of about 250° C., which is the maximum temperature expected at the second face of the panel if the extreme temperature conditions do not exceed 730° C. for a period of 15 minutes and the maximum temperature does not exceed 840° C. Thus, upon distortion of the outer sheet under extreme temperature conditions, the frame is not caused to distort other than slight or minor distortion. The selection of steel for the frame is considered appropriate for the temperature limit discussed above, while steel also advantageously is capable of gentle distribution of heat throughout the frame structure as the temperature on the internal side of the shutter increases, rather than abrupt distribution or uneven distribution. By this gentle overall increase of the frame temperature, distortion of the frame is minimised.
[0027] A seal can be disposed between the side edge regions of the shutter and facing surfaces of the surrounds or frame of the window, door or opening within which the shutter is mounted. The seal can be provided to minimise air exchange from the external side of the shutter to the internal side, and to prevent passage of embers and gases from the external side.
[0028] An effective form of seal is an intumescent seal, which increases in volume as the ambient temperature increases. Accordingly, during a fire event, the seal will expand and more firmly engage between the shutter and the frame of the window, door or opening, forming a barrier against air, embers or gases. The advantage of an intumescent seal is that the seal has minimum volume at ambient temperature so that it can be arranged not to interfere with the operation of the shutter in normal temperature conditions. However, the seal expands and forms an interference fit with facing surfaces when the temperature rises to extreme levels. In testing which has been conducted to date, a seal under the name Lorient HP1602AS has been successfully employed.
[0029] A seal can also be employed between adjacent shutter leaves and between adjacent sections of a shutter. In fact, a seal can be employed at all joins and openings within the shutter and between the shutter and the surrounds or body within which the shutter is mounted.
[0030] A shutter according to the invention can provide an effective barrier against ingress of heat and embers or direct flame to a window, door or other opening to protect the window, door or other opening from failure and thus to protect the building in which the window, door or other opening is installed. A shutter according to the invention can also reduce the temperature increase within the building during an external extreme temperature event, by limiting the transfer of heat from outside the building to inside through the window, door or other opening. Thus, any occupants of the building are likely to be exposed to reduced temperature and are more likely to survive the extreme temperature event. It is to be noted that in bushfires, the fire tends to move through an area relatively quickly and so the period in which building and the building occupants must survive is often a period of minutes rather than hours, but the intensity of the fire is often extremely high for that short period. In testing of a shutter according to the invention undertaken to date, the shutter has survived under simulated extreme bushfire conditions for a typical period under which a building would be subject to the bushfire.
[0031] For a better understanding of the invention and to show how it may be performed, embodiments thereof will now be described, by way of non-limiting example only, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIGS. 1 to 3 illustrate three different prior art shutter arrangements.
[0033] FIG. 4 is a horizontal section of a shutter according to one embodiment of the invention.
[0034] FIG. 5 is a vertical section of the shutter of FIG. 4 .
[0035] FIGS. 6 to 9 illustrate variations of portions of the shutter illustrated in FIGS. 4 and 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0036] FIGS. 1 a and 1 b illustrate a 4 panel bi folding “casement” shutter 10 in a respective fully open position ( FIG. 1 a ) and a fully closed position ( FIG. 1 b ). FIG. 1 a illustrates a pair of bi-fold shutters sections 11 and 12 , each formed by a pair of shutter leaves 13 and 14 which are fitted to cover an opening represented by broken line 15 . The opening can be closed by a window or door (not illustrated).
[0037] The shutter leaves 13 and 14 are of equal dimension and each of the shutter leaves 13 is connected to the associated shutter leaf 14 by hinges 16 . Likewise, each of the shutter sections 11 and 12 is connected by hinges to the frame or surrounds of the window by hinged connection of the leaves 13 with the frame or surrounds.
[0038] In FIG. 1 a, the shutter leaves 13 and 14 are folded open completely, so that shutter leaf 14 overlies shutter leaf 13 , and each shutter section 11 and 12 is fully hinged so that the opening 15 is fully exposed.
[0039] Suitable latching arrangements can be employed to retain the shutter sections 11 and 12 in the fully open position of FIG. 1 a, while the same latching arrangements or different latching arrangements can be employed to retain the shutter sections 11 and 12 closed in the FIG. 1 b illustration.
[0040] The casement shutter 10 is a form of shutter which exists already and which is easily moved between open and closed positions. Such shutters are therefore popular as covers for windows. However, the casement shutter 10 has not heretofore been used as a fire barrier.
[0041] FIGS. 2 a and 2 b illustrate a double panel casement shutter 17 , while FIGS. 3 a and 3 b illustrate a single panel casement shutter 18 , each in closed and open conditions respectively. In each case, the shutter leaves 19 are hinged to the window frame for movement between open and closed positions.
[0042] Applicant has developed a shutter arrangement which can form a barrier across a window, door or other opening or the like to protect the window, door or opening against exposure to extreme high temperatures, such as those experienced during an intense bushfire. As explained earlier, openings such as windows and doors are prone to fail during an extreme temperature conditions and allow ingress of flame and embers, and oxygen. Accordingly, protecting windows and doors against failure is important in protecting a building against destruction by fire.
[0043] A shutter according to the invention can be formed as a casement shutter of the styles depicted in FIGS. 1 to 3 . Alternatively, a shutter according to the invention can be similar to that depicted in FIGS. 1 a and 1 b , but with a tri-fold arrangement, or greater. Moreover, while the leaves of the shutters illustrated in FIGS. 1 to 3 are hinged along a vertical line, the leaves could be hinged along a horizontal line so that the leaves fold vertically.
[0044] FIGS. 4 and 5 illustrate cross-sectional views of a shutter according to the invention through horizontal and vertical sections respectively. Referring first to the horizontal cross-section of FIG. 4 , this depicts a shutter 20 which is fixed over or in front of a window assembly 21 . The window assembly consists of a double glazed window pane 22 which is mounted within side styles 23 . No further discussion will be made in relation to the window assembly 21 given that the window assembly 21 is not important in relation to describing the invention, although it will be appreciated that the shutter 20 of the invention is provided for the purpose of protecting the pane 22 against failure, and for resisting ingress of flame and embers to the window assembly 21 .
[0045] The shutter 20 includes a pair of shutter sections 25 and 26 each of which could be formed in a single or bi-fold manner, as illustrated in FIGS. 1 and 2 . The shutter sections 25 and 26 thus include separate shutter leaves 27 and 28 . The shutter leaves 27 and 28 would be connected by one or more hinges (not shown) to further shutter leaves if the shutter sections 25 and 26 were bi-fold sections.
[0046] The shutter sections 25 and 26 are connected to opposite vertical frame assemblies 35 and 36 . Each of the frame assemblies includes an angle section 37 which is fixed to the window surround 38 in any suitable manner. The frame assemblies 35 and 36 include hinges (not shown) to which the shutter sections 25 and 26 are connected. The frame assemblies 35 and 36 include a metal frame 42 which cooperates with the angle section 37 . The frame assemblies 35 and 36 can include an infill 41 within the metal frame 42 to support a screw 43 which extends through the frame 42 and the infill 41 and into the angle section 37 to secure the frame 42 to the angle section 37 . The infill can be of any suitable material. An alternative arrangement employs a metal box section, ie 30×30×2.5 mm SHS, to replace the frame 42 and the infill 41 .
[0047] The shutter leaves 27 and 28 each comprise an outer metal sheet 50 and a non-combustible insulating panel 51 . The outer sheet 50 is disposed on the fire-side or external side of the shutter 20 , and it can be seen from both FIGS. 4 and 5 , that the outer sheet 50 provides complete coverage for the facing surface of the panel 51 .
[0048] On the opposite or internal side of the panel 51 , a frame 52 is located and this comprises a square frame formed of 20×20×2.5 mm SHS section. The frame 52 is formed as a rectangle, about the periphery of the panel 51 .
[0049] A rear metal panel 53 extends across the internal side of the shutter 20 and is formed of 0.5 mm steel sheet. The metal panel 53 is attached to the rear side of the frame 52 .
[0050] The frame 52 includes a flange or channel 54 which defines a front lip 55 , a rear lip 56 and a base 57 . The flange or channel 54 accepts the periphery of the outer sheet 50 , the insulating panel 51 , and the rear panel 53 . The flange or channel 54 extends fully about the periphery of the respective outer sheet 50 , the insulating panel 51 and the rear panel 53 .
[0051] A seal 58 is disposed between the flange or channel 54 and the metal frame 42 of the frame assemblies 35 and 36 of FIG. 4 and the further frame assemblies 59 and 60 of FIG. 5 . The frame assemblies 35 and 36 extend along the side edges of the shutter sections 25 and 26 , while the frame assemblies 59 and 60 extend across the top and bottom edges of the shutter sections 25 and 26 . The frame assemblies 59 and 60 are formed in the same manner as the frame assemblies 35 and 36 and therefore the same reference numerals are employed for the same parts.
[0052] The seals 58 are intumescent seals as described earlier. A further intumescent seal 61 is positioned between the angle section 37 and the frame 42 . The seals 58 are prepared seals whereas the seals 61 are a liquid sealant which is applied as one of the last installation steps during installation of shutters according to the invention.
[0053] The shutter 20 is easily fitted to the reveal of an existing window, door or other opening. FIG. 5 illustrates a screw 62 which extends through the window surround 38 and it is the case that this form of fixing can be employed about the complete periphery of the shutter 20 . The method of assembly, is that the angle sections 37 are first secured to the window surround 38 , where after the remaining shutter components are fixed to the angle section 37 via the screw 43 . Once that fixing has taken place, the intumescent sealant 61 can be applied to finalise the installation process. The use of the sealant 61 provides some flexibility with tolerances in fitting the shutter 22 a window, as the gap into which the sealant 61 is applied might vary between different windows.
[0054] Once installed, it will be appreciated that with the various seals 58 and 61 , that the shutter 20 in a closed condition forms a complete barrier against ingress of embers and direct flames to the window assembly 21 . Referring to FIG. 4 , it can be seen that the seals 58 close all of the gaps in the shutter structure, including between shutter sections 25 and 26 . While not illustrated in FIG. 4 , similar seals 58 can be employed between respective shutter leaves in a bi-fold shutter arrangement.
[0055] Moreover, the resistance to conduction of heat from an external side of the shutter to an internal side, protects the window assembly 21 from the extreme heat on the external side of the shutter 20 during an extreme temperature event, such as a bushfire.
[0056] To maintain the shutter 20 in a closed condition, suitable latches can be employed and in testing conducted to date, zinc plated steel padbolts have been employed. However, it is clear that various other latching arrangements could be employed, but what is required is that the padbolt, if applied to the external side of the shutter 20 , be able to survive temperatures of the kind that the outer sheet 50 is required to survive and for the same timeframes.
[0057] Several variations of the shutter 20 illustrated in FIGS. 4 and 5 have been devised at this stage and include variations illustrated in FIGS. 6 to 9 . Referring to FIG. 6 , this variation involves the extension of the rear panel 53 of FIGS. 4 and 5 about the side edges of the frame 52 , the insulating panel 51 and the outer sheet 50 . Thus, instead of the arrangement of the shutter 20 , in which a separate channel 54 is provided, in the FIG. 6 arrangement, the rear panel 65 extends to a side portion 66 and to a front lip portion 67 . The side and front lip portions 66 and 67 are formed integrally with the rear panel 65 .
[0058] In FIG. 7 , a variation is provided in relation to the frame 42 and the infill 41 of the shutter 20 . Instead of the frame 42 and the infill 41 , a SHS 70 is provided through which the screw 43 extends. It is expected that this variation will be employed in practice, although testing to date has not been conducted in relation to this variation and therefore it remains an option only.
[0059] The variation illustrated in FIG. 8 is similar to the variation of FIG. 7 , except that a screw 71 extends through the angle section 37 and into only one portion of the SHS 70 .
[0060] The variation of FIG. 9 shows the SHS 70 being fixed directly to the wall face 72 which surrounds a window by a screw 73 .
[0061] The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the present disclosure.
[0062] Throughout the description of this specification the word “comprise” and variations of that word, such as “comprises” and “comprising”, are not intended to exclude other additives or components or integers. | A shutter 20 including an outer sheet 50 and a non-combustible insulating panel 51. The panel 51 is positioned between the outer sheet 50 and a frame 52. The outer sheet 50 overlies a broad face of the panel 51 and the frame 52 is attached adjacent to a second broad face of the panel 51 opposite the first broad face. The outer sheet 50 has a melting point of greater than or equal to about 840° C. The panel 51 is operable to retard heat transmission from the first face to the second face so that when the first face is exposed to a temperature of 730° C. for a period of 15 minutes, the temperature of the second face does not exceed 250° C. Each of the outer sheet 50 and the panel 51 are secured to the frame 52 and the frame is substantially resistant to distortion of up to a temperature of about 250° C. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims priority from provisional application Nos. 60/628,311, filed Nov. 16, 2004, and 60/662,469, filed Mar. 17, 2005, the contents of both of which are herewith incorporated by reference.
BACKGROUND
Technolines LLC has been granted a number of patents, including U.S. Pat. No. 5,990,444 and others, which describe lasers being used to write graphic images and patterns on substrates. The lasers may write graphic images on fabric substrates such as cotton, polyester, suede, leather, and the like. The laser should write with an output power or energy “density” per unit time, or EDPUT, that makes a mark on the fabric, without undesirable damage to the fabric.
SUMMARY
The present application describes a technique of treating fabrics prior to and/or after marking them with a laser. The treatment allows the laser to make a better sustainable mark on the fabric (specifically after repeated washes or wear).
According to a first aspect of the invention, a method of producing a sustainable laser-scribed graphic image on a cotton garment is provided. The cotton garment contains a dye imparting an appearance of a first color other than white to the cotton garment. An area but less than all of the cotton garment is pre-treated with a curable pre-treatment material, and the pre-treatment material on the pre-treated area of the cotton garment is cured. A laser scribes a graphic image in the pre-treated area, the graphic image having a second color sufficiently different in appearance from the first color to establish a visibly perceivable contrast between the first and second colors. The cured pre-treatment material improves sustainability of the visibly perceivable contrast against repeated washings.
According to a second aspect of the invention, a method of producing a sustainable laser-scribed graphic image on a cotton garment is provided. The cotton garment contains a dye imparting an appearance of a first color other than white to the cotton garment. A graphic image is laser scribed in an area of the cotton garment, the graphic image having a second color sufficiently different in appearance from the first color to establish a visibly perceivable contrast between the first and second colors. The lazed portion but less than all of the cotton garment is treated with a curable treatment material, and the treatment material is cured. The cured treatment material improves sustainability of the visibly perceivable contrast against repeated washings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 show embodiments of the system with a pretreatment, and laser marking part.
DETAILED DESCRIPTION
The general structure and techniques, and more specific embodiments which can be used to effect different ways of carrying out the more general goals are described herein.
A basic embodiment is shown in FIG. 1 . FIG. 1 shows the operation along a conveyor 100 , however, it should be understood that the operation can be carried out in one place, or as part of any other kind of workstation. A workpiece, e.g., a fabric item, or clothing part, shown as 99 , is exposed to the output of a laser 105 . A controller 110 controls the laser. The controller may be internal to the laser 105 or may be completely separate. The controller causes the laser to output a beam which has an energy amount that causes a change to the look of the fabric. The energy amount may be set as an energy density per unit time, which may avoid undesirable damage to the fabric and may alter the fabric chemistry. The controller, for example, may be a computer that is controlled according to a prestored program. The program may include an image of a design to be scribed. The design may be image portions representing words, or may be image portions representing an actual image, such as a logo. The computers described herein may be any kind of computer, either general purpose, or some specific purpose computer such as a workstation. The computer may be a Pentium class computer, running Windows XP or Linux, or may be a Macintosh computer. The programs may be written in C, or Java, or any other programming language. The programs may be resident on a storage medium, e.g., magnetic or optical, e.g. the computer hard drive, a removable disk or other removable medium. The programs may also be run over a network. FIG. 2 illustrates the incorporation of the invention in a typical screen printing carousel operation. For those skilled in the art, it is apparent that the traditional multiple arms which apply different colored paints to the fabric via individual screen printing, can be situated anywhere along the carousel shown in FIG. 2 .
It has been observed that most textile substrates are very responsive to the laser writing process. After the textile is processed by the laser, it is desirable that the image that was written during the operation should be seen immediately, and that the image is also seen later—e.g., after wearing or washing. However, on certain garments, and specifically on some cotton materials, the graphic has been observed to disappear or reduce in contrast after washing. The kinds of materials, and the reasons why this happens are unknown. The materials and results have not been easily susceptible of prediction.
For example, this problem could exist on one specific dyed cotton material. However, the problem might not exist on a similar dyed cotton material of the same color. Some colors tend to produce better laser-scribed graphics than others. There has been minimal consistency between the processes. For example, scribed graphics on blue and red cottons have tended to look better after washing then the same graphics lazed on black or pink cottons.
It is postulated that variations in the yarn, weaving, dyes, retention techniques or other material variation might be responsible for the inconsistent problem. However, this problem prevented laser scribed graphics from being used on all dyed fabrics; while also withstanding repeated washing.
The inventor believed that there must be some spray or surface treatment which could change the characteristics of the material, here cotton, to allow the scribed graphics to withstand repeated washings. A variety of different surface treatments were investigated. A specific product called PermaFresh® (a modified compound of DMDHEU: dimethylol-dihydroxy-ethyleneurea) was found from a chemical company called Omnova. The PermaFresh product is a total fabric treatment for stain and wrinkle resistance. This treatment is meant to remain bound to the fabric for the life of the fabric, and to withstand washing.
Permafresh surprisingly proved to essentially eliminate the post wash characteristic problem when processing laser scribed graphics on many different dyed materials and colors. Other analogous materials may also be used, which will have similar results.
The PermaFresh compound is applied, and heat cured, to alter the surface chemistry of the material in some way. Element 120 illustrates the fabric pretreatment process, where the sprayer 120 sprays the material 125 on to the workpiece 99 prior to laser scribing. The heat curing may be a totally separate step along the conveyor, or may rely on the heat produced by the laser 105 itself. This allows the laser-written graphics to appear crisp and clean even after repeated washings. This also made it possible, and also facilitates the laser writing of the graphics on certain cotton colors such as black and pink. Laser writing on black and pink has historically been difficult or impossible prior to this pretreatment technique.
A post treatment step 130 applies a post treatment material on to the workpiece. The post treatment may simply be for example from the heat flow, or may be either another wrinkle resistance material or the same wrinkle resistance material. Heat may serve to further fix the wrinkle resistant material in place. Typically the heat application is applied after the spaying operation and before the lazing operation. An additional post treatment as in step 180 in FIG. 2 could actually cool the spayed and heated material.
The conveyor may also include a washing station shown as 140 . Washing station 140 may apply soap, using brushes as shown, and may vacuum away the soap residue, and/or may also provide a rinse operation to the material after the soap has been applied or may only provide a rinse function. Alternatively, a more conventional washing machine can be used, instead of doing this along the conveyor. The washing operation would be carried out after all laser marking and heating steps are complete.
While PermaFresh has been described as the one pretreatment material, it should be understood that any treatment process that remains bound to the fabric for the life of the garment may be able to be similarly used. More specifically, any such treatment product which provides stain and/or wrinkle resistance and/or other kind of treatment to the material which changes the characteristic of the material, may be used. It may be postulated that the stain protection somehow chemically alters the surface to allow it to retain the laser formed image after washing. The pretreatment that is used should preferably be liquid, it should preferably remain bound to the fabric for either the life of the fabric or at least for a number of washing cycles of the fabric, and it should at least in one embodiment, have the function of at least one of wrinkle and/or stain resistance.
A method comprising treating a fabric material with a treatment that remains bound to the fabric and is intended to change some characteristic of the fabric to make the fabric more resistant and using a laser to form a perceivable change to a color of the fabric without undesirably damaging the fabric.
Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventor (s) intend these to be encompassed within this specification. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. This disclosure is intended to be exemplary, and the claims are intended to cover any modification or alternative which might be predictable to a person having ordinary skill in the art. For example, other materials, that is, other than Permafresh may be used. An important part of the material is that it alters the characteristic of the fabric, and in a specific way. The fabric's characteristic should be altered in a way that makes it more resistant. Wrinkle resistance and stain resistance are two exemplary ways in which the characteristic should be altered.
Also, the inventor(s) intend that only those claims which use the words “means for” are intended to be interpreted under 35 USC 112, sixth paragraph. Moreover, no limitations from the specification are intended to be read into any claims, unless those limitations are expressly included in the claims. | Pretreatment of a fabric using a material that binds to the fabric and changes some characteristic of the fabric. In an embodiment, the characteristic that is changed can be at least one of stain and flash for wrinkle resistance. The material can be Permafresh material. The material can bind to the fabric, and intends to be maintained within the fabric for the life of the fabric. After pretreatment, the pretreated material is processed by a laser which intends to change the look of the material without undesirably damaging the material. The treatment may make the treatment by lasers more consistent and allow the lazed graphic to maintain its quality after repeated washings and wearing. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an automatic cable attenuation compensation system.
As a consequence of the skin effect, coax cable attenuation expressed in dB increases with the frequency of the transmitted signal in proportion to the root of this frequency. The attenuation is further dependent on, inter alia, the length and the diameter of the cable. Such an attenuation is especially disturbing when baseband video signals are transmitted, while in the case of transmission of double-sided amplitude modulated signals, the relatively less attenuated left side-band and the relatively more attenuated right side-band can be combined to obtain a substantially flat amplitude characteristic. Such an easy compensation is not available when baseband video signals are transmitted.
2. Description of the Related Art
In applications where video signals have to be transmitted over relatively long coax cables of variable length, (semi-)automatic cable attenuation compensation systems are used. DE-A-31.48242 discloses a system which determines the cable length at power-up to switch on a fixed compensation suitable for compensating the frequency-dependent attenuation within certain limits for one type of coax cable in steps of several meters. This step-wise compensation entails the drawback that any cable attenuation which is within the resolution of the attenuation compensation system is not compensated for, so that no optimal flat frequency characteristic for intermediate cable lengths is obtained. Further, such step-wise cable attenuation compensating systems may only be operative directly after power-up, because a step-wise adjustment of the compensation at a later stage would result in a disturbed picture. This entails the drawback that any temperature-dependent attenuation caused by temperature changes cannot be compensated for.
On the other hand, U.S. Pat. No. 3,431,351 discloses an automatic frequency characteristic correction system which provides a continuous compensation of the frequency-dependent attenuation. The compensation range of such a continuously operative compensator is, however, rather small, so that no adequate compensation is obtained when the attenuation effected by the cable falls outside this range.
SUMMARY OF THE INVENTION
It is, inter alia, an object of the invention to provide an improved automatic cable attenuation compensation system. For this purpose, a first aspect of the invention provides an automatic cable attenuation compensation system comprising a fixed compensation part (FC-R/G/B) providing a stepwise adjustable attenuation compensation for substantially compensating cable attenuation, the stepwise adjustable attenuation compensation of the fixed compensation part being set after power-up, and an adaptive compensation part (VC-R/G/B) providing a continuously active compensation for a further compensation of the cable attenuation.
As a consequence of the addition of the adaptive compensation part providing a continuously active compensation for a further accurate compensation of the cable attenuation, to the prior an stepwise adjustable fixed compensation pan, both the remaining cable attenuation falling between the steps of the stepwise fixed compensation, and any temporal (temperature-dependent) variations in the attenuation, are corrected, while the overall system has a large correction range.
If the cable is a multi-core cable having a plurality of channels for, for example, R, G, and B signals, the adaptive compensation part advantageously includes a separate, independent adaptive compensator for each channel to avoid that mutual differences between the channels are not compensated for when the attenuation of only one channel is measured to obtain a control signal for all channels. In the compensation system of U.S. Pat. No. 3,431,351, the compensation to be applied to one wire of the cable is based on a DC attenuation measured in another wire of the cable, with the disadvantage that the mutual differences between the wires are not taken into account.
A high quality flat frequency response is obtained if the adaptive compensation pan includes a first automatic gain control for compensating for an attenuation of a low-frequency test signal included in the signal transmitted over the cable, and a high-frequency automatic gain control for compensating for an attenuation of a high-frequency test signal included in the signal transmitted through the cable.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 shows an embodiment of an automatic cable attenuation compensation system in accordance with the present invention;
FIG. 2 shows an embodiment of a compensation section for use in the embodiment of FIG. 1; and
FIG. 3 shows a block circuit diagram of an automatic gain control circuit for use in the embodiment of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In one embodiment of the invention, a first test signal having a continuous amplitude equal to the maximum value of the video signal is added to the video signal during at least one active line period in the vertical blanking interval, while a second test signal forming a sine wave of the same amplitude and a frequency of about 2/3 of the maximum pass-bandwidth is added to the video signal during at least one other active line period in the vertical blanking interval. For example, when the pass-bandwidth is 30 MHz, a frequency of 18 MHz is chosen, while a frequency between 3 and 5 MHz can be chosen with a pass-bandwidth of 5.5 MHz.
The automatic cable attenuation compensation system shown in FIG. 1 comprises, in each channel R, G, B, a fixed compensation part FC-R, FC-G, FC-B, respectively, as well as variable compensation parts VC-R, VC-G, VC-B, respectively. The fixed compensation parts include a plurality of switchable compensation sections CS each capable of compensating for a predetermined amount of cable attenuation. At the highest frequency of the video band, one compensation section CS may compensate for 1 dB, 2 dB, 4 dB, 8 dB or 16 dB. The compensation section (CS 16 dB) providing the largest compensation may appear more than once.
In at least one channel, the blue channel B in the embodiment of FIG. 1, the cable attenuation compensation system comprises a sample and measuring circuit M furnishing enabling control signals EN through a control signal bus to enable the switchable compensation circuits CS. The line numbers of the first and second test signal lines are known to the system, so that the corresponding sampling signals for the test signals can be generated. The required switchable cable attenuation compensation is automatically determined at power-up. The compensation starts at 0 dB and is increased by steps of 1 dB (at the maximum frequency) until a reference level in the sample and measuring circuit M is obtained. The enabling control signals EN furnished by the sample and measuring circuit M ensure that this state is maintained. The start-up procedure is repeated after each interruption of the signal. More specifically, the amplitude of the sine wave second test signal is measured, and compensation sections CS are switched on and off in steps of 1 dB until the sine wave amplitude of the transmitted second test signal just exceeds the maximum video signal amplitude. Then, the measurement is finished and the measuring circuit M freezes its output control signals EN. If the video signal disappears, the measuring circuit M resets itself, so that the measurement is repeated when the video signal re-appears.
The variable compensation sections VC-R, VC-G, VC-B of the cable attenuation compensation system comprise in each channel R, G, B, a continuous (wide-band) automatic gain control amplifier WB-AGC for the complete signal and a continuous automatic gain control amplifier HF-AGC for the high-frequency part of the signal, whose amplification increases with the root of the frequency. Both AGC circuits HF-AGC, WB-AGC include sample circuits for the continuous amplitude first test signal and the sine wave second test signal, respectively, as well as the required continuous control circuits.
The maximum 1 dB deviation in the frequency-characteristic caused by the compensation magnitude of the smallest compensation section (CS 1 dB) of the fixed compensation parts FC-R, FC-G, FC-B, plus the mutual differences in cable attenuation of the different coax cables used in the multi-core cable, and the cable attenuation variations appearing during operation of the system caused, for example, by temperature variations of the cables or of the circuits employed, are measured in each channel R, G, B during each field period and compensated for by means of the two continuous AGC amplifiers in the variable compensation parts VC-R, VC-G, VC-B, so that the frequency characteristics of the signals remain optimally flat.
A novel feature provided by the present invention is the addition of continuously operational cable attenuation compensation systems in the variable compensation parts VC-R, VC-G, VC-B. The new system comprises the following major features:
1. The video signal compensation is fully automatic.
2. The video signals are individually and optimally compensated with a maximally flat frequency characteristic, notwithstanding mutual spread in properties of the coax cables used.
3. This optimal compensation operates continuously to remove attenuation variations in cables and circuits which are caused, for example, by temperature variations.
4. The system is capable of working with other cables without adjustments as long as the maximum cable attenuation is within the total range of the compensation circuits.
5. The system can be used in two directions, so that return video signals from the camera processing unit to the camera, such as viewfinder and teleprompter signals, are corrected too.
FIG. 2 shows an example of a compensation section CS suitable for use in the fixed compensation part of FIG. 1. The input of the section is coupled to an inverting input of an amplifier AMP through the parallel circuit of a resistor R6 and the series circuit of a filter RC and a switch SW controlled by the enabling control signal EN of the compensation section CS. The amplifier AMP is fed back by means of a resistor R7. The non-inverting input of the amplifier AMP is connected to ground, and its output is connected to the output of the compensation section CS. In dependence on the enabling control signal EN, such a section operates as an inverting buffer or as a cable compensation section. The RC filters R1, C1, R2, C2, R3, C3, R4, C4, R5 are designed in such a way that one section CS yields a maximal compensation of 16, 8, 4, 2 or 1 dB at 30 MHz, while the transfer function is proportional to the root of the frequency.
FIG. 3 shows a block circuit diagram of a combination of AGC circuits HF-AGC, WB-AGC suitable for use in the variable compensation pans VC-R, VC-G, VC-B. The input of the circuit HF-AGC is coupled to the inverting input of a differential amplifier (subtracter) DA through a low-pass filter LPF and to the non-inverting input of the amplifier DA through a high-pass filter HPF and an AGC circuit AGC1. The output of the amplifier DA forms the output of the circuit HF-AGC which is connected to the input of the circuit WB-AGC. The control signal for the circuit AGC1 is derived from the output signal of the automatic cable attenuation circuit at the output of the circuit WB-AGC in the following manner. The output signal is full-wave rectified by a rectifying circuit D, and subsequently sampled by a sampling circuit S11 which samples the continuous maximum amplitude first test signal and by a sampling circuit S2 which samples the sine wave second test signal. The difference between the sampled amplitudes of the first and second test signals is determined and integrated by a circuit Int1 which furnishes the control signal for the AGC circuit AGC1.
The circuit WB-AGC comprises an AGC circuit AGC2 whose input is coupled to the output of the circuit HF-AGC and whose output furnishes the output signal of the automatic cable attenuation circuit. The control signal for the circuit AGC2 is derived from this output signal by a sampling circuit S12 which samples the continuous maximum amplitude first test signal, and by a circuit Int2 which determines and integrates the difference between the sampled amplitude of the first test signal and a reference signal having the maximum amplitude of the video signal.
In a preferred embodiment of the automatic cable attenuation in accordance with the present invention, one of the goals was to automatically compensate for any cable length. This is realized by dividing the total compensation into a fixed part and an adaptive part.
The fixed part can compensate any cable length with a resolution of 12.5 m. This length is determined at power-up, by means of a successive approximation measurement, viz. the total compensation in the fixed part is increased until the (18 MHz) HF-burst signal amplitude in the vertical gap of one video channel is its original, known, value.
The adaptive part, which is independent in each channel and continuously active, has two functions:
1. It has to compensate the last few meters of the multi-core cable which are within the resolution of the fixed part.
2. It has to compensate (frequency dependent) loss differences which might be caused by, for instance, temperature changes of the multi-core cable and/or differences between the individual coaxes.
The invention thus provides a system for automatic continuous individual cable attenuation with optimum flat frequency response for baseband video signals transmitted via coax or multi-core cable.
It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. | In an automatic cable attenuation compensation system comprising a fixed compensation part (FC-R/G/B) providing a stepwise adjustable attenuation compensation for substantially compensating cable attenuation, the stepwise adjustable attenuation compensation of the fixed compensation part being set after power-up, an adaptive compensation part (VC-R/G/B) is provided for a continuously active compensation for a further accurate compensation of the cable attenuation. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a retractable handle mounting assembly for a travel bag, and more particularly to such a retractable handle mounting assembly which can be conveniently operated with one hand.
FIG. 1 shows a travel bag with a retractable handle according to the prior art. This retractable handle comprises two sleeves mounted inside the bag body of the travel bag, two inner tubes joined by a hand grip outside the sleeves and moved in and out of the sleeves, lock means adapted to lock the inner tubes inside the sleeves, and control means mounted in the hand grip and controlled to release the lock means from the inner tubes. This structure of retractable handle is functional, however it still has a drawback. When the lock means is released from the inner tubes, the user shall have to force down the bag body of the travel bag with one hand and then to pull up the hand grip with the other hand, i.e., the retractable handle cannot be conveniently operated with one hand.
SUMMARY OF THE INVENTION
It is the main object of the present invention to provide a retractable handle mounting assembly for a travel bag which can be conveniently operated with one hand. According to the preferred embodiment of the present invention, the retractable handle mounting assembly comprises two sleeves connected between a casing and a sleeve holder, two inner tubes joined by a hand grip and moved in and out of the sleeves, two stop members adapted for locking the inner tubes in the received position inside the sleeves, a control knob adapted for releasing the stop members from the inner tubes, two springy or resilient locating devices adapted for locking the inner tubes in the extended position outside the sleeves, two control rods controlled by a press control device to release the springy locating devices from the inner tubes, and two spring devices respectively mounted on the inner tubes and adapted to push the inner tubes upwardly out of the sleeves when the inner tubes are released from the stop members.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a travel bag with a retractable handle according to the prior art;
FIG. 2A is an exploded view of a first part of the present invention;
FIG. 2B is an exploded view of a second part of the present invention;
FIG. 3 is a perspective assembly view of the present invention, showing the retractable handle mounting assembly installed, the inner tubes extended out;
FIG. 4A is a partial view in section of the present invention, showing the inner tubes received inside the sleeves and locked;
FIG. 4B is similar to FIG. 4A but showing the stop rods of the stop members disengaged from the inner tubes;
FIG. 4C is another sectional view of the present invention, showing the inner tubes extended out of the sleeves; and
FIG. 4D is still another sectional view of the present invention, showing the inner tubes pushed back to the inside of the sleeves.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 2A, 3 and 4A, a casing 10 is fixedly mounted on a travel bag 100 over the connecting area between the top and back sides of the travel bag 100, comprising a top receiving chamber 11, two tubular flanges 12 bilaterally and downwardly extended from its bottom side and having a respective transverse through hole 121 at an inner side, two through holes 111 respectively communicating between the top receiving chamber 11 and the inside of the tubular flanges 12, a control box 13 raised from its bottom side and spaced between the tubular flanges 12, a button hole 112 disposed in the middle between the through holes 111 corresponding to the control box 13. A sleeve holder 15 is fixedly mounted on the back side of the travel bag 100 near the bottom. Two sleeves 14 are connected in parallel between the sleeve holder 15 and the tubular flanges 12 of the casing 10. Each sleeve 14 comprises an inside flange 142 downwardly extended from its topmost edge on the inside, a transverse outside through hole 141 made through the periphery and disposed in alignment with the transverse through hole 121 of the corresponding tubular flange 12, an upper inside through hole 143 made through the inside flange 142 and disposed in alignment with the transverse outside through hole 141 and the transverse through hole 121 of the corresponding tubular flange 12, and a lower inside hole 144 spaced below the upper inside through hole 143. A control knob 20 is mounted in the control box 13. The control knob 20 comprises a base 201 stopped below the button hole 112 and having an outer diameter greater than the diameter of the button hole 112, a knob head 202 protruding out of the button hole 112, two downward lugs 203 downwardly extended from the bottom side of the base 201 in the middle, a spring 204 fixedly fastened to the bottom side of the base 201 between the downward lugs 203, and two bevel blocks 205 respectively extended from two opposite ends of the base 201. Two stop members 21 are respectively coupled to the bevel blocks 205 of the control knob 20. Each stop member 21 comprises a base 211, a bevel hole 212 at one end of the base 211 for receiving the bevel blocks 205 of the control knob 20, two parallel upright guide blocks 213 raised from the base 211 in the middle top and adapted to move along the top wall of the control box 20, and a stop rod 214 horizontally extended from an opposite end of the base 211 and inserted into the transverse through hole 121 of one tubular flange 12 and the transverse outside through hole 141 of one sleeve 14. A bottom cover 22 is covered on the bottom open side of the control box 13, having a plurality of mounting holes 221 fixedly fastened to the control box 13 by for example screws 222, an upright rod 223 raised from its top side in the middle which holds one end, namely, the bottom end of the spring 204, and two upright lugs 224 adapted to receive the downward lugs 203 of the control knob 20.
Referring to FIGS. 2A and 4A and FIG. 3 again, two inner tubes 16 are respectively inserted through the through holes 111 of the casing 10 into the sleeves 14, having a respective bottom end mounted with a respective spring device 165. Each inner tube 16 comprises a top notch 162 at an inner side, a first locating hole 161 and a second locating hole 161' vertically spaced below the top notch 162, and a third locating hole 163 disposed at an outer side opposite to the second locating hole 161'. A hollow, bottom-open hand grip 30 is provided having two downward coupling tubes 31 at two opposite ends respectively plugged onto the top ends of the inner tubes 16, and two downward rods 301 spaced between the downward coupling tubes 31. The downward coupling tubes 31 of the hand grip 30 have a respective opening 311 corresponding to the top notches 162 of the inner tube 16. Two springs 302 are respectively mounted on the downward rods 301 of the hand grip 30. A press control device 32 is coupled to the hand grip 30 at the bottom side. The press control device 32 comprises a flat base plate 321 fitting over the bottom open side of the hand grip 30, a press block 322 raised from the bottom side of the flat base plate 321, two flanged through holes 324 disposed through the flat base plate 321 and adapted to receive the springs 302, and two coupling rods 323 respectively extended from two opposite ends of the flat base plate 321 in reversed directions and inserted through the openings 311 of the downward coupling tubes 31 of the hand grip 30 and the top notches 162 of the inner tubes 16. A hand grip cover shell 303 is covered on the bottom open side of the hand grip 30 over the press control device 32, having two mounting holes 304 near its two ends respectively fastened to the downward rods 301 of the hand grip 30, and a center opening 306 through which the press block 322 of the press control device 32 protrudes. Two screws 305 are respectively inserted through the mounting holes 304 of the hand grip cover shell 303 and the flanged through holes 324 of the press control device 32, and threaded into a respective screw hole (not shown) at the bottom end of each downward rod 301 of the hand grip 30 to fixedly secure to the hand grip cover shell 303 to the hand grip 30. Two control rods 40 are respectively mounted in the inner tubes 16. Each control rod 40 has a top coupling hole 401 fastened to one coupling rod 323 of the press control device 32, and a bottom coupling hole 402. Two elongated actuating members 41 are respectively mounted inside the inner tubes 16 and coupled to the control rods 40. Each elongated actuating member 41 comprises an elongated base 411, a coupling rod 412 perpendicularly raised from one end of the elongated base 411 and fitted into the bottom coupling hole 402 of one control rod 40, two parallel side flanges 413 perpendicularly raised along two long sides of the elongated base 411, a longitudinal sliding slot 415 through the elongated base 411 between the parallel side flanges 413, and a bevel sliding track 414 formed in the parallel side flanges 413. Two springy locating devices 50 are respectively mounted inside the inner tubes 16 and coupled to the actuating members 41. Each springy locating device 50 comprises a loop-shaped springy body 50 moved between the parallel side flanges 413 of one actuating member 41, a rear locating rod 513 raised from the loop-shaped spring body 50 at one side and fastened to the third locating hole 163 of one inner tube 16, a transverse sliding block 512 disposed at one side of the loop-shaped spring body 50 opposite to the locating rod 513 and adapted to move in the bevel sliding track 414, and a front locating rod 511 perpendicularly raised from the transverse sliding block 512 and inserted into the longitudinal sliding slot 415 of the corresponding actuating member 41.
Referring to FIG. 4A again, when the inner tubes 16 are received inside the sleeves 14, the stop rods 214 of the stop members 21 are respectively inserted through the transverse through holes 121 of the tubular flanges 12 of the casing 10 and the transverse outside through holes 141 of the sleeves 14 into the first locating holes 161 of the inner tubes 16, the spring devices 165 of the inner tubes 16 are compressed within the sleeves 14 at the bottom, and the hand grip 30 is received within the top receiving chamber 11 of the casing 10.
Referring to FIGS. 4B and 4C, when to pull the inner tubes 16 out of the sleeves 14, the knob head 202 of the control knob 20 is depressed to force the bevel blocks 205 into the bevel holes 212 of the stop members 21. When the bevel blocks 205 are forced into the bevel holes 212 of the stop members 21, the stop members 21 are forced to move inwards toward each other, thereby causing the stop rods 214 of the stop members 21 to be disengaged from the first locating holes 161 of the inner tubes 16. When the inner tubes 16 are released from the stop rods 214 of the stop members 21, the spring devices 165 of the inner tubes 16 immediately return to their former shape, thereby causing the inner tubes 16 and the hand grip 30 to be forced upwards, and therefore the user can pull the hand grip 30 upwards to move the inner tubes 16 out of the sleeves 14. When the inner tubes 16 are extended out of the sleeves 14, the front locating rods 511 of the springy locating devices 50 are forced by the spring force of the springy locating devices 50 into engagement with the transverse outside through holes 141 of the sleeves 14, and therefore the inner tubes 16 are locked in the extended position.
Referring to FIG. 4D, when to collapse the retractable handle, the press block 322 of the press control device 32 is pushed upwards against the springs 302 to lift the control rods 40. When the control rods 40 are lifted, the actuating members 41 are simultaneously moved upwards with the control rods 40, and the transverse sliding blocks 512 of the springy locating devices 50 are forced to move downwards along the bevel sliding tracks 414 of the actuating members 41, thereby causing the front locating rods 511 of the springy locating devices 50 to be disengaged from the lower inside through holes 144 of the inside flanges 142 of the sleeves 14, for permitting the inner tubes 16 to be pushed back to the inside of the sleeves 14. When the inner tubes 16 are pushed back to the inside of the sleeves 14, the control knob 20 is returned by its former position by the spring 204, and the stop rods 214 of the stop members 21 are forced by the bevel blocks 205 of the control knob 20 into engagement with the first locating holes 161 of the inner tubes 16, the upper inside through holes 143 of the inside flanges 142 of the sleeves 14, the transverse outside through holes 141 of the sleeves 14 and the transverse through holes 121 of the tubular flanges 12 of the casing 10.
While only one embodiment of the present invention has been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed. | A retractable handle mounting assembly of a travel bag, including two sleeves connected between a casing and a sleeve holder, two inner tubes joined by a hand grip and moved in and out of the sleeves, two stop members adapted for locking the inner tubes in the received position inside the sleeves, a control knob adapted for releasing the stop members from the inner tubes, two resilient locating devices adapted for locking the inner tubes in the extended position outside the sleeves, and two control rods controlled by a press control device to release the resilient locating devices from the inner tubes. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of copending International Application PCT/DE99/01948, filed Jul. 1, 1999, which designated the United States.
BACKGROUND OF THE INVENTION
Field of the Invention
In many communications systems, terminals which can be used for different purposes such as, e.g., the transmission of voice, video, fax, file, program and/or measurement data, are increasingly coupled to the systems wirelessly. Such mobile terminals are frequently coupled via a multi-channel air interface to a base station, which in turn, is connected to a communication network. In the text which follows, mobile terminals are also understood to be so-called cordless terminals. Via the base station, connections are established between the mobile terminals coupled to it and other terminating equipment connected to the communication network. In that configuration, the base station acts, among other things, as converter between transmission protocols used in the communication network and transmission protocols of the air interface.
The type of wireless network connection described is used a lot, especially in the case of mobile terminals for voice communication. In this connection, the invention relates to a communications system which is also provided for voice communication and comprises a base station which can be connected to a communication network and mobile terminals coupled to it wirelessly.
Base stations provided for voice communication have hitherto been known which have to be operated on an ISDN communication network such as, e.g. the public telephone network. It is possible to create connections between the mobile terminals and other terminating equipment connected to the ISDN communication network via such base stations. For this purpose, the base stations are equipped for converting between an ISDN transmission protocol used in the ISDN communication network and a transmission protocol of the air interface.
It is frequently also possible to transmit data of other categories such as, for example, video data or file data to be exchanged when a portable computer is connected wirelessly to a data network, between the ISDN communication network and mobile terminals via the base station in parallel with the voice transmission. Differently from digitized voice signals which are to be transmitted at their largely constant data rate, file data to be transmitted frequently, however, occur in bursts, that is to say at a greatly varying data rate. Since an ISDN communication network is designed for synchronized data transmission and does not, therefore, allow the bandwidth to be varied dynamically, an overload situation can occur during a transmission of burst-type file data if the data rate of the file data temporarily exceeds a predetermined transmission bandwidth. To avoid such a situation, the file data must either be buffered—which delays their transmission—or a transmission bandwidth must be provided which is dimensioned in accordance with the peak data rate to be expected, which is often relatively high.
In many cases, data must be exchanged between a mobile terminal and an external data network such as, for example, the Internet or another network provided for the communication of data processing systems. However, in the case of a base station which must be operated on an ISDN communication network, such a data exchange requires an additional facility such as, e.g. a modem or a so-called gateway computer by means of which the data are converted between the external data network and the ISDN communication network.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a wireless communications system which overcomes the above-noted deficiencies and disadvantages of the prior art devices and methods of this general kind, which is also provided for voice communication and which is equipped with at least one base station and mobile terminals coupled to it wirelessly and which allows a data exchange via external data networks with little expenditure.
With the above and other objects in view there is provided, in accordance with the invention, a communications system with a base station and mobile terminals. The novel communications system has the following characteristics:
the base station has an air interface for implementing wireless, first partial connections to the mobile terminals and a network interface to a communication network configured to establish second partial connections to further terminals, wherein voice data to be transmitted in each case are transmitted within data packets to be transmitted asynchronously for the first and second partial connections; the individual data packets each contains an address information item unambiguously specifying one of the mobile terminals or further terminals in the communication network as a transmission destination and directing the data packets to the respective transmission destination within the communication network; the base station includes a router configured to allocate data packets arriving in existing first or second partial connections to second or first partial connections in dependence on the address information item contained in each data packet; and the mobile terminals have voice compression devices for compressing voice data to be transmitted from the mobile terminal to the base station, and/or voice decompression devices for decompressing voice data received by the respective mobile terminal.
An essential advantage of the communications system according to the invention consists in that it can be coupled directly to a packet-switching communication network such as, for example, the Internet or a data network, via the base station. This does not require additional facilities for converting data to be exchanged with the communication network such as, e.g., a modem or a gateway computer. Since transport of voice data or other user data in a communications system according to the invention such as in a packet-switching communication network is based on the asynchronous transmission of data packets, the data packets can be exchanged directly between the communications system according to the invention and a packet-switching communication network when a common transmission protocol such as, e.g., the Internet protocol is used. The communications system according to the invention can thus be integrated into a packet-switching communication network with little expenditure which is an advantageous characteristic particularly with regard to the present development of ever more powerful packet-switching communication networks.
Furthermore, data of other categories such as, e.g., video, fax, file, program or measurement data can also be transmitted in addition to voice data, within data packets to be transmitted asynchronously by means of the communications system according to the invention. The data packets are forwarded by the router by means of an address information item contained in the respective data packets. Since data packets can be forwarded independently of the category of data contained in the data packets, no discrimination or special treatment of data of different categories is required in the base station. Differentiation with respect to the category of the data to be transmitted is only necessary in a respective destination terminal. This makes it possible to transfer the advantages associated with an integrated voice and data transmission in wire-connected packet-switching communication networks to wireless communications systems.
A further advantage of the communications system according to the invention consists in that a transmission rate with which voice data or data of other categories are transmitted can be easily adapted to the current data volume by correspondingly varying the rate at which the data packets to be transmitted are generated and/or transmitted.
A voice compression device contained in the mobile terminals is used for compressing the voice data to be sent via the air interface, as a result of which less transmission bandwidth is occupied in the air interface. Correspondingly, a voice decompression device contained in the mobile terminals is used in decompressing voice data received via the air interface which has been compressed before the transmission via the air interface in order to relieve the latter.
In accordance with an added feature of the invention, the communication network is a data network for connecting data processing systems.
The communications system according to the invention can be implemented by air interfaces according to different standards and a number of standards can also be combined. Advantageous embodiments are obtained in particular with air interfaces according to the ETSI Standards DECT (Digital Enhanced Cordless Telecommunications), DCS (Digital Cellular System) or GSM (Global System for Mobile Communication) or an air interface according to the UMTS definition (Universal Mobile Telecommunications system) proposed for standardization; also by means of air interfaces according to the ARI standard PHS (Personal Handyphone System).
In accordance with an advantageous feature of the invention, the network interface is configured for connections to a switching system in an ISDN network.
In accordance with an advantageous feature of the invention, the base station contains a detector by means of which it is possible to check by means of priority information contained in individual data packets, whether the applications to which the data packets are allocated are quasi-real-time applications with predetermined maximum permissible packet transmission period. According to this further development of the invention, the base station also contains a prioritizing device which initiates a preferred transmission of data packets allocated to a quasi-real-time application. In a preferred transmission of data packets, it is also possible to take into consideration several different classes of priority to which the data packets are allocated by means of the priority information contained therein.
According to a further advantageous development of the invention, the base station can also contain a voice compression device and/or a voice decompression device. The voice compression device is used for compressing uncompressed voice data to be transmitted by the other terminals to the mobile terminals before they are transmitted via the air interface. Correspondingly, the voice decompression device is provided for decompressing compressed voice data to be transmitted by the mobile terminals to the other terminals before they are transmitted into the communications system. A base station which is equipped in this manner has the advantage that it is also possible to exchange uncompressed voice data with the further terminals coupled to the communication network which dispenses with the necessity of harmonizing the voice compression methods used in the communications system according to the invention and in the other terminals.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a wireless communications system, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of a communications system comprising a base station and mobile terminals which are coupled to other terminals via the base station;
FIG. 2 is a schematic block diagram of the base station; and
FIG. 3 is a schematic block diagram of a mobile terminal.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is seen a communications system comprising a base station BS and mobile terminals E 1 and E 2 coupled to it wirelessly. In this configuration, a wireless connection is in each case indicated by stylized lightning arrows. The base station BS is also connected to a communication network KN, e.g. to the Internet or to another data network provided for the communication of data processing systems. Further terminals E 3 and E 4 are coupled to the data network, which supports an Internet protocol (IP) in the exemplary embodiment. In addition, an unambiguous (with respect to the communication network KN) network address, i.e. in this case an IP address IP 1 , and respectively, IP 2 , is in each case allocated to the mobile terminals E 1 , E 2 . In addition, the mobile terminals E 1 , E 2 are registered in the base station BS as being available via the base station BS.
In the present exemplary embodiment, a voice connection exists in each case between the mobile terminal E 1 and the further terminal E 3 and between the mobile terminal E 2 and the further terminal E 4 . In these voice connections, voice signals to be transmitted from the further terminals E 3 , E 4 to the mobile terminals E 1 , E 2 , respectively, are digitized and compressed in order to reduce the data volume to be transmitted. The compressed voice data are then inserted as user data ND 1 and, respectively, ND 2 into data packets to be transmitted asynchronously. These packets are provided with an address information item identifying their respective transmission destination, i.e. with the IP addresses IP 1 and, respectively, IP 2 of the mobile terminals E 1 and E 2 , and transmitted into the communication network KN. In the communication network KN, the data packets are forwarded to the base station BS by means of their attached IP addresses, IP 1 , IP 2 in accordance with the Internet protocol. From the base station the data packets are transmitted to the mobile terminals E 1 and, respectively, E 2 via the air interface.
Referring now to the diagram of FIG. 2 , the base station BS contains as functional components a transceiver SEB, a router ROU and a network interface NS for connecting the base station BS to the communication network KN. In this configuration, the router ROU is connected, on the one hand, to the network interface NS via which data can be exchanged with the communication network KN and, on the other hand, coupled via logical or physical ports P 1 , P 2 , . . . PN to the transceiver SEB. The transceiver SEB implements an air interface, for example according to the DECT standard, to the mobile terminals E 1 , E 2 and provides a number of wireless transmission channels for an exchange of digital data between the base station BS and mobile terminals E 1 , E 2 . In this configuration, the wireless transmission channels are in each case allocated to one of the ports P 1 , P 2 , . . . PN.
In the voice connections to the mobile terminals E 1 , E 2 , the data packets with the user data ND 1 and, respectively, ND 2 and the IP addresses IP 1 and, respectively, IP 2 , which are transmitted to the base station BS via the network interface NS, are supplied to the router ROU by the network interface NS. In the router ROU, the IP address of each incoming data packet is read and the transmission destination of the data packet, which is specified by the IP address, is determined. Afterward, a check is made whether this transmission destination is a mobile terminal that can be reached via the base station BS. If this is so, a transmission channel of the air interface which is available for a connection to this mobile terminal is also determined, whereupon the data packet is transmitted to the transceiver SEB via a port P 1 , P 2 , . . . or PN allocated to the transmission channel found. In the exemplary embodiment, the mobile terminal E 1 is coupled to the base station via a transmission channel allocated to the port P 1 and the mobile terminal E 2 is coupled to the base station via a transmission channel allocated to the port P 2 . Correspondingly, the data packet identified by the IP address IP 1 is transmitted via the port P 1 and the data packet identified by IP address IP 2 is transmitted via the port P 2 to the transceiver SEB. From the transceiver SEB, the data packets received via the ports P 1 and P 2 respectively, are then transmitted via the transmission channels of the air interface which are allocated to the ports P 1 and P 2 , respectively, to the mobile terminals E 1 and E 2 , respectively.
Quasi-real-time transmission requires the allocation of the maximum available bandwidth and priority handling over non-critical or not-so-critical transmission. Accordingly, the base station may be equipped with a detector device DET which checks the data packets with respect to quasi-real-time requirements of applications allocated to the data packets. Such quasi-real-time requirements are contained in priority information items in individual data packets. A corresponding prioritizing device PRIO in the base station (BS) then initiates a preferred transmission of the data packets that are found to be allocated to quasi-real-time applications.
FIG. 3 shows a diagram of the mobile terminal E 1 . It contains as functional components a transceiver SEE, a conversion module UM, a compressing/decompressing device KD and an input/output module SIO for voice data. The individual functional components are connected in series in the order in which they have been enumerated.
The data packet containing user data ND 1 and IP address IP 1 , which is sent to the mobile terminal E 1 in the voice connection, is received by the transceiver SEE and forwarded to the conversion module UM. In the conversion module UM, the user data ND 1 are extracted from the data packet and assembled with the extracted user data contents of other data packets transmitted in the voice connection to the terminal E 1 , to form a continuous user data stream. The conversion module UM is frequently also called segmentation and reassembly module. The extracted user data ND 1 are then supplied as part of the user data stream to the compressing/decompressing device KD where the user data ND 1 or, respectively the user data stream, are decompressed. As a result of the decompression, the original digitized voice signals DND 1 are reconstructed from the user data ND 1 and are finally supplied as part of a decompressed user stream to the input/output device SIO where they are output as speech.
To transmit voice signals also in the reverse direction, i.e. from the mobile terminal E 1 to the further terminal E 3 , in the voice connection, the sequence described above must be appropriately reversed. In this case, the voice signals are input in the input/output device SIO from where they are supplied in digital form to the compressing/decompressing device KD to be compressed. The compressed voice data are then inserted in the conversion module UM into data packets which are provided with the IP address of the further terminal E 3 and are wirelessly transmitted to the base station BS by the transceiver SEE. In the base station BS the received data packets are then transmitted by the transceiver SEB via one of ports P 1 , P 2 , . . . PN to the router ROU where the IP addresses of the data packets are used for deciding where a particular data packet is to be forwarded to. In the present case, the router ROU detects that the destination terminal E 3 specified by the IP address does not belong to the mobile terminals E 1 , E 2 coupled to the base station BS and therefore forwards the data packets provided with this IP address into the communication network KN via the network interface NS. In the communication network KN, the data packets are then forwarded by means of the IP addresses in accordance with the Internet protocol to the terminal E 3 where the voice data are extracted from the data packets and, after decompression, are output as speech. | A communications system includes a base station and mobile terminals. Voice data are transmitted within data packets in asynchronous transmission. The base station has an air interface for implementing first partial connections to the mobile terminals and a network interface to a communication network via which second partial connections to further terminals can be implemented. The base station also contains a router for allocating data packets which arrive in existing first or second partial connections to second or first partial connections. The allocation is done in dependence on an address information item which specifies a terminal in the sense of a transmission destination and is in each case contained in the individual data packets. The mobile terminals also contain in each case a voice compression device and/or a voice decompression device. | 7 |
This application is a continuation of application Ser. No. 08/186,548, filed on Jan. 26, 1994, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a finisher for finishing sheets for use in a copier, printer or similar image forming apparatus and, more particularly, to a finisher having a sorter for sorting sheets for a plurality of bins, and further having a stapler or a punch device.
2. Description of the Prior Art
Recently, various finishers which use helical cam shifts and have a plurality of bins moveable in the vertical direction have been proposed.
In the above-mentioned finisher, the space between a bin and an adjacent bin is relatively narrow in a waiting condition of an image forming apparatus, and the space between the first bin moved to the position at which image formed sheets are discharged and the second bin located at the position just above the first bin (such finisher being described in Japanese patent application Laid Open No. 64-64973/1989) is relatively broad in a sheet discharging condition.
A sufficient space between the top sheet in the bin for discharging sheets and the bin located at a position above the top sheet is necessary for accurately positioning the discharged sheets in the bins. If not enough space is provided, it is difficult to attain accurate positioning of the discharged sheets in the bin for discharging sheets. Because the curled sheet relatively forcefully touches the top sheet or the bin located at the position above the top sheet, it makes it difficult for sheet discharge into the preferred position of the bin. Furthermore, movement of the discharged sheet on the top sheet by a jogger is relatively difficult from the discharged position to a predetermined position.
On the other hand, in a sorter having the moveable bins, it is necessary that the next bin be moved to the sheet discharging position by completion of the period during which the next sheet may be discharged after the finished sheet is discharged into the bin.
FIG. 1 is a timing chart concerning bin movement and jogger movement of a prior art apparatus. In the figure, the jogger is the device for aligning sheet sides in the bin "T 1 " (sec) shows the sheet discharging cycle, in which the sheet discharging is detected by a sensor, and "t" shows the period during which the discharging sheet drops into the bin and the sheet is moved to the end edge portion of the bin. The bin which is located at the discharging position has a space with a dimension of "45" mm in the upward direction of the bin and then the bin is moved up to the not-discharged position, wherein the space is "15" mm which is the regular spacing. The corresponding CPM (copying per minute) of the image forming apparatus is 60/T.
In order to attain high-speeding operations of the finisher, it is possible to perform the following steps.
(1) decrease the moving time of the bins
(2) decrease the operation time of the jogger
(3) speed up sheet discharging to the bin
However, each step has the following shortcomings: As for item (1), it is necessary to employ an expensive motor. As for item (2), it is difficult to perfectly align the sides of the discharged sheet and as for item (3), the sheets are incorrectly stacked so that the sheets are aligned in a disorderly manner.
Furthermore, in order to attain high-efficiency operations of the finisher, it is possible that the finisher causes the jogger to align the sheets and thereby the bin moves at the same time.
However, if the bin space located over or under the bin, into which sheets are discharged, is established so as to be the same as the space formed by each of the other bins, the space which is formed by each of bins changes so as to be narrower corresponding to the bin's movement (for example, the space changes from 45 mm to 15 mm). This narrow space causes the side of the stacked sheets to be aligned in a disorderly manner, because the discharged sheets abut against the bins.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide an improved finisher for an image forming apparatus, in which the above-mentioned conventional apparatus shortcomings are eliminated. More specifically, it is an object of the present invention to provide a finisher for an image forming apparatus which is capable of causing the jogger to operate for aligning the side of the sheets and movement of the bin at the same time, and attain high-efficiency operations for arranging sheets
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 is a timing chart concerning bin movement and jogger movement of a prior art apparatus.
FIG. 2 is a front view showing an embodiment of a finisher according to the present invention.
FIG. 3 is a plan view showing an embodiment of the finisher according to the present invention.
FIG. 4 is an enlarged front view of bin portion showing an embodiment of the finisher according to the present invention.
FIG. 5 is a timing chart concerning bin movement and jogger movement of an embodiment of the finisher according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 2, a discharging sheet from a main body 1 of an image forming apparatus of a preferred embodiment of the present invention is divided into a proof tray section and a bins section by a guide pawl 2.
To begin with, a mechanism for feeding sheets to a proof tray 5 and its operation are explained. An operating portion (not shown) of a copier of the present invention is started and run by a starting signal and a signal for deciding the sheet discharging position from the main body 1, and the guide pawl 2 is moved downward. The discharged sheet from the main body 1 is guided by the guide pawl 2, fed by a pair of feeding rollers 3 and a pair of discharging rollers 4, and is discharged into the proof tray 5. Problems such as jamming of sheets are detected by a sensor 6 located at the entrance of the finisher F and by a sensor 7 located at the entrance of the proof tray 5.
Next, a mechanism for feeding sheets to the bins sections and sorting operation thereof is explained. The operating portion (not shown) is started and run by the starting signal and the signal for deciding the sheet discharging position from the main body 1, and the guide pawl 2 is moved upwardly. The discharged sheet from the main body 1 is guided therein by the guide pawl 2 and fed by three pairs of feeding rollers 8, 9 10 functioning as a sheet feeding member. Thereafter, the discharging sheet is discharged into a first bin 12-1 for accepting the discharged sheet by a pair of rollers 11. A plurality of the bins 12 are arranged in a vertical direction.
The linear velocity for discharging a sheet from the rollers 11 is reduced and the sheet is discharged to the first bin 12-1. In this embodiment, the first linear velocity is 1000 mm/sec, and this is reduced to 600 mm/sec at a position 30 mm before the first bin 12-1.
The completion of sheet discharging is detected by a sensor 13 for detecting sheet discharging into the first bin 12-1. After completion of sheet discharging, the discharged sheet falls down into the end portion 12a of the bin. Furthermore, after about 300 msec elapses from the completion of sheet discharging, a jogger shaft 14 as an aligning member moves in the drawing-up direction as shown in FIG. 3 and touches the side portion of the sheets in bins 12. The sheets in the bins 12 are moved to each of a plurality of standard fences 15, wherein the standard fences 15 are also used as a side fence of the bins 12 for aligning the side of the sheets. Herein, the jogger device comprises the jogger shaft 14, a shift motor, a timing belt, a pulley, etc.
At the same time as the sheet-aligning operation by the jogger shaft 14 occurs, each of three helical cam shafts 16 acting as a bin moving member rotates by one rotation and moves the plurality of bins up or down. The helical cam shafts 16 have spiral cam grooves which are provided with an equal pitch and spiral cam grooves which have an unequal pitch.
Each of guide pins 20, which is provided at each of the sides of the bin, is guided by each of the spiral cam grooves of the helical cam shafts 16. A guide slit 19 provided on a side wall of the finisher F also guides the guide pins 20 in the vertical direction. The helical cam shaft 16 is rotationally driven by a stepping motor (not shown). Each of helical shafts 16 rotates in the regular forward direction or in a reverse direction, and the bins 12 move upward or downward. It takes 400 msec for the plurality of the bins 12 to move from a particular bin's position to the next bin's position corresponding to one rotation of the helical cam shafts 16. The above-mentioned series of operations are repeated to sort and align the side of the sheets.
Problems such as jamming of the sheets are detected by the sensor 6 located at the entrance of the finisher F and the sensor 13 for detecting sheet discharging into the first bin 12-1. After completing sorting operation of the discharged sheets, a bin end fence 17 is released and the respective stacked sheets in the bin 12, which is located at the position of a second bin 12-2 shown in FIG. 2, are moved by a chuck unit (not shown) moving toward a stapler 18. The stacked sheets are stapled by the stapler 18. The chuck unit is moved in the reverse direction and the stacked and stapled sheets are returned from the stapler position into the bin 12-2. The bin end fence 17 is closed and then the plurality of bins 12 are moved upward or downward. The above-mentioned series of operations for stapling sheets is repeated for stapling sheets from the beginning.
In FIG. 2, the first bin 12-1, into which the sheet is discharged, is located at a position facing toward the rollers 11 and the second bin 12-2, which is the bin for performing subsequent processing such as stapling, is located at a position just under the first bin 12-1 and faces toward the stapler. A sufficient interval between the first bin 12-1 and the second bin 12-2 is established for moving the chuck unit, as will be described later in detail.
In this embodiment, twenty bins are utilized and the plurality of bins 12 comprise the first bin 12-1, the second bin 12-2, a third bin 12-3, a fourth bin 12-4, a fifth bin 12-5 and other regular bins. As shown in FIG. 4, each of the intervals "E" between the other regular bins is 15 mm, an interval "A" between the first bin 12-1 and third bin 12-3 located at a position just over the first bin 12-1 is 45 mm, an interval "B" between the first bin 12-1 and the second bin 12-2 located at a position just under the first bin 12-1 is 40 mm, an interval "C" between the second bin 12-2 and the fourth bin 12-4 located at a position just under the second bin 12-2 is 40 mm and an interval "D" between the third bin 12-3 and fifth bin 12-5 located at a position immediately above the third bin 12-3 is 30 mm. The above-mentioned intervals are established by each of the spiral cam grooves of the helical cam shafts 16 in accordance with the relationship of the following inequality: A≧B≧C≧D≧E such that at least the first, second, third bins are directly adjacent to one another and have greater intervals therebetween than the interval E between the other regular bins, as is shown in FIG. 4.
The spiral cam grooves 16a are formed in the helical cam shafts 16 so as to position each of bins with the above-mentioned relationship.
Therefore, when each of helical shafts 16 rotates in the regular direction and the bins 12 move upward, the respective bins 12 move from the respective particular bin's position to the next upper bin's position corresponding to one rotation of the helical cam shaft 16 and the newly positioned bins keep the above-mentioned relationship of intervals by the helical cam shafts 16.
The intervals "A", "B" and "C" are kept relatively broad during the period of the bin's moving. Therefore, when the jogger operates to align the sheets, there are sufficient intervals for the respective adjacent bins to prevent the sheets from abutting the lower surface of the bin located at the upper position of the sheet.
Furthermore, sufficient intervals "B" and "C" are necessary for moving the chuck unit toward the stapler 18. Therefore, the interval "B" and "C" are broader than the intervals of the regular bins.
FIG. 5 is a timing chart showing bin movement and jogger movement concerning the embodiment of the finisher according to the present invention.
In comparison with FIG. 1, the sheet discharging period "T 2 " in FIG. 5 is shorter than the operation time of the bin lifting movement. This is because the finisher F causes the jogger to operate for aligning sheets and the finisher F causes the bin to move at the almost same time.
Assuming that the sheet size is A4 (its width being 210 mm), the discharging velocity is 600 mm/sec, the waiting time for starting the jogger operation is 300 msec, the jogger operation time is 250 msec, and the bin movement time is 450 msec.
In the prior art,
T.sub.1 =(210/600)×1000+300+250+450=1350 (msec)
Therefore, the corresponding CPM of the image forming apparatus equals 44.4 (60/T 1 =60/1.35).
In the present invention, however,
T.sub.2 =(210/600)×1000+300+250=900 (msec.)
Therefore, corresponding CPM (copying per minute) of the image forming apparatus equals 66.7 (60/T 2 =60/0.9), and the copying efficiency is thus increased by approx. 50%.
In above-mentioned embodiment, the sheet-discharging can be performed smoothly and the loading capacity can be increased, because the space above the first bin 12-1, the space above the third bin 12-3 located at the upper position of the first bin 12-1 and the space above the second bin 12-2 located at the lower position of the first bin 12-1 can be made relatively broad.
The interval between the respective adjacent bins can be kept relatively broad during the period of the bin's moving. Therefore, when the jogger operates to align the side of the sheets, there is a sufficient interval between the respective adjacent bins to prevent the sheet from abutting on the lower surface of the bin located at the upper position of the sheet.
It is possible that the finisher causes the jogger to operate for aligning the side of sheets and moves the bins at the same time without causing stacked sheets to be aligned in a disorderly manner. As a result, the embodiment attains a high-CPM.
On the other hand, the intervals between the adjacent regular bins are established so as to be a minimum, and therefore a compact-size finisher can be provided.
Furthermore, in the above-mentioned embodiment, if the sheet has a curled portion, the discharged sheets are aligned without suffering from the influence by the lower surface of the above bins. This is because the intervals A, B and D are made over two times as broad as the interval between the adjacent regular bins.
Hereinbelow, the basis of the above-noted phrase "over two times" is described briefly. In the case of stacking the fifth sheets, the thickness of the sheet is about 13 mm. Namely, an "about 13 mm" interval between the bins is necessary for stacking the sheets in the bin. However, considering that curled sheets exists and the sheets are jogged to be aligned, a "more than about 10 mm" interval is necessary to add to the above interval of "13 mm". The necessary interval adds up to over "23 mm". Therefore, it is necessary that the intervals A, B and D be over two times as broad as the interval between the regular bins.
Obviously, numerous modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A finisher for finishing sheets for use in a copier, printer or similar image forming apparatus having a sorter for sorting sheets on a plurality of bins, and further having a stapler or a punching device. A bin moving member is provided for moving the plurality of bins to predetermined positions in which the bin moving member moves the bins to a positioning relationship such that an interval A between a first bin for accepting the discharged sheets from a discharging member and a third bin located at a position immediately over the first bin, an interval B between the first bin and a second bin located at a position immediately under the first bin, and an interval D between the third bin located at a position immediately over the first bin and a fifth bin located at a position immediately over the third bin are broader than an interval E between other adjacent regular bins. | 1 |
RELATED APPLICATIONS
This application is a continuation-in-part of co-pending application Perlman, VORTEX MIXING IMPLEMENT FOR MICROCENTRIFUGE TUBES, U.S. patent application Ser. No. 08/590,552, filed Mar. 19, 1996, now abandoned, which is hereby incorporated by reference in its entirety including drawings.
BACKGROUND OF THE INVENTION
This invention relates to the use of a mixing implement during vortex-agitation of a laboratory sample, the implement functioning to accelerate the mixing of liquids and/or dispersal of solids contained within a laboratory microcentrifuge tube or sample vessel, and while in place, not interfering with centrifugal fractionation of the sample.
Microcentrifuge tubes, also known as microtubes, are small plastic vessels which are typically tapered and closed at one end, and have a conical or rounded bottom. The polyethylene or propylene tubes are generally capable of holding between 0.2 and 2.0 ml of liquid, and are constructed to withstand forces typically in excess of 10,000 times their own weight (10,000×g) during centrifugation. These tubes are used widely in biotechnology laboratories as vessels for mixing and reacting chemical substances, separating and purifying liquid and solid materials by centrifugation, handling radioisotope chemicals, storing biochemicals, and containing, mixing, or incubating contaminant-free samples. They have tight-fitting hinged or screw-top lids whose size and shape protect, cover, and hermetically seal the perimeter of the tube opening, and help maintain the inside of the tube in an aseptic condition.
Vortex-agitation is a process of rapid gyro-rotary mixing of a liquid sample in a container such as a test tube or microtube as described above. Liquid flow during vortexing is generally circular in direction around the major vertical axis of a container, such as test tube Vortexing is typically accomplished by placing the bottom of the tube into the cup-shaped rubber adapter portion of an electrically powered vortexing machine which, when activated, initiates gyratory motion of the rubber cup. Vortexing is often used to agitate small volumes of liquid held in plastic microtubes. These volumes are limited by the capacity of the commercially available microtubes which currently can hold up to approximately 2.0 milliliters. The practice of vortexing substances in microtubes is used in a wide variety of applications such as dissolving reagents, resuspending pellets (produced by centrifugation of particulate suspensions such as bacterial or eucaryotic cells or adsorbent materials, etc.), emulsifying liquids (during solvent extraction, protein denaturation and removal, etc.) and for many other mixing applications. Typical microtubes with tapered, conically-shaped lower portions are convenient for centrifugation but because the lower portion is narrow near the bottom, it can be difficult to achieve rapid motion of liquid for resuspending sedimented material, etc. during vortexing. Yet vigorous agitation is required for resuspension of cell pellets, dissolution of solutes, emulsification of liquids, and the like.
Several mechanical stirring and mixing devices are in current laboratory use for producing movement of liquids and solids in small vessels. These devices include a motorized, magnetically driven magnetic stirring bar, a manually rotated stirring rod for test tubes and an electrically driven propeller stirrer. The magnetic stirring bar rotates horizontally against the bottom of a flat-bottomed vessel and produces a rotational flow of a liquid. The test tube stirring rod and the propeller stirrer are operated by external shafts which extend upward beyond the lip of the vessel. None of these devices has any relevance for improving the process of vortex-mixing of samples. Applicant is, however, familiar with the addition of small glass beads to liquid suspensions of cells in test tubes to promote cell breakage by vortexing. When utilized in a microcentrifuge tube for mechanical agitation, the above devices are routinely removed from the tube prior to centrifugation to allow normal pellet formation if suspended solid material is present.
Another type of mixing device is described in Kaspar et al., CONTAINER ASSEMBLY FOR VISCOUS TEST SPECIMENS MATERIALS, U.S. Pat. No. 4,514,091, Issued Apr. 30, 1985. A homogenization rod having a generally helical or coil shape is described. The rod is designed to dislodge material from a specially formed cavity in the underside of the top cover of a container, which is also described, as the container is agitated back and forth along its longitudinal axis in a generally reciprocal motion, markedly different from the high speed circular flow generated by vortex agitation.
SUMMARY OF THE INVENTION
Prior to the present invention, Applicant could find no convenient means to improve the efficiency of the vortexing process as routinely used for emulsifying liquids and resuspending or dissolving solid materials in small sealed laboratory vessels such as microtubes, vials, and the like. In particular, Applicant observed that while vortexing could be used to induce rapid circular motion of liquids, the efficiency of mechanical disruption of solids and the efficiency of resuspending sedimented samples adhered to the sidewalls of a vessel were limited. The addition of a small amount of glass beads for sample agitation was considered and ruled out because of the inconvenience of subsequently removing the beads from the sample and because of the loss of sample material within the mass of beads. Likewise, the helical rod device of Kaspar et al. was not suitable for vortex agitation because it tends to roll around the inner wall surface of the tube rather than scraping the wall, and because the helix structure tends to embed itself within sedimented material on the lower sidewall of the centrifuge tube.
To improve vortexing efficiency (mixing, mechanical disruption of suspended and adhered solid materials, and multi-directional flow of liquids), Applicant has experimented with the addition of single objects of different shapes as vortex-mixing implements or agitators. These agitators have included regularly and irregularly shaped balls, blocks, pyramids, etc. fabricated from glass or plastic. An unexpected problem was discovered during experimental trials with each of these agitators. As the vortexing speed increased, each agitator was propelled upward toward the lid of the microtube or vial, rather than remaining near the bottom of the vessel where it was needed for mechanical contact and displacement of solid material. To solve this problem, applicant has devised a geometry for the agitator which maintains the agitator in a substantially vertical (upright) orientation in the microtube during vortexing, but at the same time does not substantially restrict its motion or speed which is required for its effectiveness as a mixer. Accordingly, Applicant has found that a tall rod or straight wand-shaped plastic agitator whose length is greater than the maximum inner diameter of the microtube but less than the maximum inner height of the tube is an effective vortexing device. The device (hereinafter termed a mixing implement or vortex agitator or vortex implement) can be configured with an approximately round, triangular, square or even polygon cross-section. During vortexing, as the vortex agitator is accelerated around the inner perimeter wall of the microtube and begins to climb the sidewall, it is blocked or deflected by the underside of the vessel's lid, e.g., the microtube lid.
In connection with the vortex mixing implements, the term "straight" indicates that there are no significant bends within the implement, while the term "substantially straight" means that, for example, the ends of the implement may be rounded or there may be a small symmetrical curvature to the exterior of the implement along the longitudinal axis creating a slightly convex exterior as seen in a longitudinal cross-section. The implements of this invention do not include objects having greater than about 10 degrees of curvature to the longitudinal axis of the object, and thus do not include coils, circles, and C- or U-shaped objects. Preferably the implements of this invention are straight, but usually substantially straight implements may also be used.
Thus, the term "rod" or "wand" refer to an object which is straight or substantially straight.
"Substantially upright" means that the mixing implement forms an angle of less than 90 degrees to the longitudinal axis of a vessel, preferably less than 70 degrees, more preferably less than 45 degrees, and still more preferably less than 30 degrees. Thus, the implement cannot invert about its long axis within the tube, or bind and lodge by bridging across the inner diameter of the vessel.
As described below, a straight implement is able to provide effective vortex mixing. The rod or straight wand shape allows the object to gyro-rotate in a high speed circular motion while also having sufficient freedom to migrate up and down within the sample vessel, thereby scraping the side wall of the sample vessel. It was found that such action, especially such wall scraping action, is not provided by other tested implements which are not substantially straight wand or rod shaped objects, such as the helical rod of Kaspar et al. In addition, the straight wand or rod shape allows the implement to remain in a vessel, such as a microcentrifuge tube during centrifugation without substantially interfering with pellet formation or sediment retention. The straight rod typically contacts only the very bottom of the tube and the upper sidewall, rather than the lower sidewall where centrifugal pellet formation occurs, thereby bridging over a pellet. Thus, the straight shape and smooth exterior of the implement allows a pellet to form and/or the implement to be removed from a vessel following centrifugation with no or little disturbance of a pellet in that vessel.
For the vortex agitator to achieve speed and mobility which are important to its efficacy, it is important that the vortex agitator be neither to large nor too heavy in relationship to the microtube or other similar vessel. Accordingly, the volume of the vortex agitator should not exceed 20%, and preferably 10% of the volume of the vessel. The weight of the agitator is preferably, similarly scaled to the aqueous sample capacity of the vessel. For example, a very effective polypropylene vortex agitator having a 2 mm diameter and 2.2 cm length has been fabricated for use in a 1.5 ml capacity microtube. Its approximate volume and weight are 0.070 ml and 0.063 gm representing approximately 4-5% of the volume and aqueous weight capacity of the microtube. A similarly effective but smaller agitator having a 1.3 mm diameter and 1.4 cm length has been fabricated for use in a 0.5 ml capacity microtube. Its volume corresponds to approximately 4% of the volume of the microtube.
In a conical-bottomed tube it is often useful for the bottom of the agitator rod to move, i.e., migrate, up and down over the conical inner wall of a tube as the rod is rotating and revolving at high speed around the axis of the tube, so as to contact any solid material such as sedimented cells, DNA, RNA protein, etc. on this inner wall portion and help in dislodging the material. Accordingly, the length of the vortex agitator is ideally equal to or shorter than 95% of the maximum inner height of the sealed tube to allow this upward and downward displacement motion of the agitator during vortexing. However, by making the length of the agitator at least 50% of the inside height of the sealed microtube, there is overlapping coverage of the inner wall surface of the microtube by the agitator as it gyrates and moves up and down inside the microtube, alternately in contact with the bottom and then the lid's underside. Accordingly, the length of the vortex agitator is most preferably between 50% and 95% of the maximum inner height of the sealed microtube. The vortex agitator can be used in liquid(s) either with or without solids or pelleted material present. Used with a microtube, the vortex agitator is dropped into the vessel along with other substances. During vortexing, the agitator moves rapidly around the inner perimeter wall of the microtube, generally at a different speed than the liquid. The combination of the agitator's rotation and gyration (gyro-rotation), and its promotion of turbulent liquid flow, accelerates essentially any mixing process such as dissolution of solids and liquid emulsification within the microtube. Moving contact between the vortex agitator and the sidewall of the microtube is particularly useful in dislodging and resuspending solids located on the bottom and on the sidewall of the microtube such as pellets of centrifuged cells and macromolecules as described above. In addition, because the vortex agitator remains upright in the microtube, it may be easily removed following use (see FIGS. 2 and 4 below), and does not interfere with centrifugation of emulsions, suspensions, etc. or the concomitant formation of sedimented pellets. For example the surface of the agitator is free of any substantial concave blemishes or other depressions which could trap rather than shed sedimenting solids and interfere with centrifugation of suspensions of various materials.
Applicant has compared the rate of resuspending identically sedimented pellets of Escherichia coli cells in 1.5 ml capacity microtubes (resuspending 1.0 ml of sedimented stationary growth phase E. coli cells into 0.10 ml of isotonic saline), both in the presence and absence of a vortex agitator of the present invention. While achieving complete resuspension of the cells by vortexing without the vortex agitator required 45-60 seconds, the presence of the vortex agitator reduced the cell resuspension time to as little as 10 seconds. Similar very substantial reductions in required vortexing time have been measured for emulsification of liquids, dissolution of salts, and other mixing procedures regularly carried out in microtubes and other small vessels using the vortexing method.
Thus, in a first aspect, the invention features a method for improving the efficacy of vortex-mixing a liquid sample and/or dispersing solids by utilizing a mixing implement, the mixing implement, while in place, not interfering with centrifugal fractionation of that sample. The method involves placing a mixing implement in a microcentrifuge tube or similar sample vessel (the microcentrifuge tube and sample vessel collectively termed "vessel") along with the sample. The presence of the upright mixing implement in the tube does not substantially interfere with centrifugal fractionation of the sample. The method includes the steps of providing a rod or straight wand-shaped mixing implement in which the length of the mixing implement is greater than the maximum inner diameter of the vessel but less than the maximum inner height of this vessel when sealed so that the mixing implement is constrained to remain substantially upright within the vessel. The mixing implement is configured and arranged to shed, i.e. release, any sedimenting solid material contained in the liquid sample which may be propelled onto the mixing implement during centrifugation. More specifically, the surface of the implement is free of any substantial depressions, concave blemishes, and the like which would receive and trap sedimenting material during centrifugation. The sample and the mixing implement are placed in the vessel which is then positioned in a holder and/or adapter element of a vortex-mixing machine. Vortex-mixing is then commenced, and the mixing implement moves and/or gyro-rotates rapidly around the inner sidewall of the vessel thereby accelerating the mixing process.
In preferred embodiments, the method additionally includes the steps of placing the microcentrifuge tube or vessel containing the sample and the mixing implement into a suitably configured and sized centrifuge rotor, and centrifuging and fractionating the sample. During centrifugation, the mixing implement sheds, i.e. releases any sedimenting solid material which may be propelled onto this mixing implement during centrifugation.
In another preferred embodiment, the length of the mixing implement is between 50% and 95% of the maximum inner height of the vessel when sealed, and the surface of the mixing implement is free of any substantial depressions such as concave blemishes which may trap sedimenting solid material contained in said sample, where the solid material may be propelled onto the mixing implement during centrifugation.
In still another preferred embodiment, after the sample and mixing implement are placed in the vessel, the vessel is sealed using a closure selected from the group consisting of a hinged lid, a screw cap, a plug seal, and a flexible covering material.
In other preferred embodiments, the rod or straight wand-shaped mixing implement is formed from a material selected from the group consisting of a thermoplastic resin, glass, metal, and composite resin. These materials provide appropriate rigidity, strength, and density for a variety of applications. This allows the implement to remain intact and undeformed during vortex mixing. In addition, these materials can be conveniently fabricated into vortexing implements. Within the category of thermoplastics, the implement can be formed from either a polyolefin, polycarbonate, polystyrene, acrylic, or a polyester material. Within the polyolefin category, either polypropylene or high density polyethylene can be selected. The method of manufacture for the mixing implement is preferably either extrusion molding or injection molding. The cross-sectional shape of the mixing implement can be selected to be either round, oval, triangular, square, or polygon. The cross-sectional shape can be selected to provide varying levels of turbulence and/or wall scraping effects during vortex mixing. The length of the mixing implement is between approximately 0.5 and 1.5 inches for use in a microcentrifuge tube whose maximum inner diameter is approximately 0.4 inch and whose maximum inner height is approximately 1.6 inches. In use, the implement of this embodiment is thereby maintained in a substantially upright position but allowed to move longitutinally. The mixing implement is useful in microcentrifuge tubes having a volume capacity ranging from approximately 0.2 to 2 milliliters. The volume of the mixing implement does not exceed 20%, and preferably is less than 10% of the volume of the vessel.
In a further embodiment, the method of this invention also involves removing the mixing implement described above from the vessel using an extraction device which allows removal of the implement while preventing contamination of the liquid and/or substantial disturbance of solid material sedimented during subsequent centrifugation. The "preventing contamination" may involve preventing the contamination of the sample with foreign microbes by providing a clean sterile extraction device adapted to allow aseptic removal of the mixing implement from the vessel. The extraction device is preferably inexpensive and may be discarded after use. Preferably, the extraction device is a straight pin or other sharp object which can be used to spear the mixing implement and lift it from the vessel, so that the method further involves spearing the mixing implement with the extraction device. Alternatively, the extraction device is an inexpensive hollow plastic straw which, when slid over the implement, captures the implement within its hollow bore, or is a magnet and the plastic mixing implement is fabricated using a ferromagnetic additive within the thermoplastic resin material such as iron, nickel, cobalt, or some combination of these metals which is attracted to this magnet allowing the implement to be removed from the vessel. In this alternative, the method involves removing the implement by magnetically attracting the implement to the extraction device and lifting the implement out of the vessel. Contamination can be prevented by using a sterilized magnet or using a sufficiently strong magnet that the implement can be removed without contacting the surface of the sample with the magnet. As a second alternative, the mixing implement can be injection-molded and configured to integrally include a semi-flexible plastic extension which protrudes out of the microtube (as an elastic spring) only when the microtube lid is opened to provide a "handle" to remove the implement by hand or by tweezers. In this second alternative, the length of the mixing implement including the semi-flexible extension is selected to be greater than the inner height of the microtube to allow easy and convenient removal of the implement. In this way, the mixing implement can be removed, while preventing contamination, by hand or using a tool (e.g., tweezers) to grasp the "handle" above the surface of the sample.
In relation to preventing contamination of a sample in the present method, "foreign microbes" refers to microbes introduced into a sample in a vessel from outside the vessel when the introduction is not intentional. The microbes may be of the same species and strain or different. Microbe has its usual biological meaning. Thus, in embodiments of the present invention, the step of removing the mixing implement can be performed without unintentionally introducing microorganisms, such as by organisms carried into the sample on an extraction device.
In a related aspect, the invention also provides a microcentrifuge tube or sample vessel which has within it a straignt wand shaped mixing implement as described above. Thus, the length of the implement is greater than the maximum inner diameter but less than the maximum inner height of the tube or vessel, so that the implement is constrained to remain substantially upright. The surface of the implement is configured and arranged to be free of substantial depressions or concave blemishes which could trap sedimenting material during centrifugation.
In another related aspect, the invention provides a kit for improving the effeciency of vortex mixing of a sample as described in the method above. The kit comprises a microcentrifuge tube or sample vessel and a straight wand shaped mixing implement as described above
Other features and advantages of the invention will be apparent from the following description of the preferred embodiments, and from the claims.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The drawings will first be briefly described.
Drawings
FIG. 1 is a perspective view, partially in section, of a microcentrifuge tube, vortex-mixing implement, liquid sample, and vortex-mixing machine of this invention.
FIG. 2 is a longitudinal sectional view of the tube, implement and sample shown in FIG. 1.
FIG. 3 is a perspective view of round, square and triangular vortex-mixing implements.
FIG. 4 is a perspective view, partially in section, of an extraction device (straight pin) being used to remove a vortex-mixing implement from a microcentrifuge tube.
Referring to the Figures, microcentrifuge tube 10 (approximate length 11/2 inches and approximate diameter 7/16 inch) is typically injection-molded from virgin polypropylene or polyethylene with lip flange 12 which can be used to support the tube in a microcentrifuge rotor or in a storage rack. Generally, the microcentrifuge tube includes a container 14 having an upper perimeter wall surface 16 (defining an upper opening 18) adapted to mate with the lower surface 22 of lid 20. Lid 20, includes lid hinge 24 and lid lifting tab 26 for opening the container 14 with either a fingernail or a container opener tool. Annular lid seal 28 (on the underside of the lid 20) provides and establishes a watertight hermetic friction-seal with the inner perimeter wall surface 30 of container 14. According to the present invention, mixing implement 32 and liquid sample 34 are placed in container 14. Different shaped mixing implements (straight extrusions with different cross-sections, see FIG. 3) are fabricated to establish different modes and degrees of agitation. Round 36, square 38 and triangular 40 cross-section implements are shown in FIG. 3. Mixing implements with sharp corners tend to produce stronger agitation than round and oval-shaped implements. Polypropylene homopolymer resins (such as Pro-Fax PD-191 from Montell USA, Inc., Wilmington, Del.) and polypropylene copolymer resins (such as Pro-Fax 7823, also from Montell USA, Inc.) which have low melt flow rates (0.4-0.8 dg/min, defined by ASTM Method D1238) are useful for extrusion-fabrication of the presently described mixing implements.
In the practice of the present invention, a single clean and/or sterile vortex mixing implement 32 (held in a polyethylene bag or other holding device containing one or more such mixing implements) is dispensed into the container 14 of microcentrifuge tube 10. A liquid sample 34 is also placed in the same microcentrifuge tube 10. Lid 20 is closed and sealed, and tube 10 is placed in rubber vortexing cup 42 of vortex machine 44 (see FIG. 1). Tube 10 in cup 42 is either hand-held or held by a mechanical adapter device (not shown) which accommodates several tubes simultaneously. As the gyro-rotary motion of cup 42 commences, mixing implement 32 is accelerated rapidly around the inner perimeter wall surface 30 of container 14 and, while moving in this gyro-rotary manner, also tends to move upward until it contacts the underside of lid 20 and may then move downward again. During this up and down, and circular cycle of motion, mixing implement 32 contacts most or all of the inner perimeter wall surface 30 of container 14, and thereby helps scrape away, resuspend and/or redissolve solid material which lies on, or has been sedimented against this wall surface 30. Likewise, mixing implement 32 can be used to accelerate emulsification of liquids, extraction of solutes from one liquid phase to another, denaturation of macromolecules or any other process which depends upon vigorous mixing of one or more liquid phases or mixing of suspensions of solid(s) in liquid(s). After vortexing has been completed, mixing implement 32 can be aseptically lifted and removed, i.e., extracted, from container 14 with a clean and sterile straight pin 46 which is first pushed into the end of this implement 32 (see FIG. 4). Alternatively, a clean sterile disposable plastic straw whose inner diameter is slightly larger than the diameter or cross-sectional span of the mixing implement 32 can be conveniently slid over the upper portion of the implement and then withdrawn from tube 10 carrying implement 32 within the hollow bore of the straw (not shown). The inner diameter of the straw is sized to provide a slight friction fit with the outside of the mixing implement.
In preferred configurations for microcentrifuge tubes, the vortex mixing implement or agitator device is generally rod or straight wand-shaped. It is inexpensive to fabricate using the extrusion-molding method, and may be discarded after use. For typically sized 0.5 ml-2.0 ml capacity microcentrifuge tubes, the mixing implement consists of a solid extruded length of plastic (such as polypropylene or polyethylene) between approximately one-half and two inches in length. It is advantageous for the implement to have a length of between approximately 50% and 95% of the maximum inner height of the sealed vessel. Specifically, if the implement is at least 50% of the sealed vessel's inner height, and the implement gyrates in both the upward and downward positions in the vessel (i.e., gyrates on the bottom and then against the top of the vessel), one can usually achieve contact during the course of the vortexing procedure, between the implement and all of the inside wall surfaces of the vessel. This is useful, for example, in dislodging and resuspending sedimented material in a microtube. The implement may have a round, triangular, square, or polygon cross-section (between approximately 0.02 and 0.20 inches in diameter, or as the side dimension for a triangle, square or polygon cross-section). A pentagonal cross-section implement has been found to be particularly useful in rotating somewhat more freely than a triangular cross-section implement, while shedding sedimented material somewhat more readily than the square cross-section implement. The surface of the implement should be free of any significant physical depressions such as concave blemishes which could trap sedimenting solid materials during centrifugation. For 1.5 milliliter capacity microtubes, for example, a polypropylene agitator rod having a length of approximately 7/8 in. and a diameter of 0.08 in. has been found to be useful, while for 0.5 milliliter capacity microtubes a similar rod having a length of approximately 9/16 in. and a diameter of 0.05 in has been found useful. Manufacture of the agitators using a low melt-flow rate polymer with a continuous extrusion and coupled transverse cutting process is preferred. Injection-molding using a higher melt-flow rate polymer provides an alternative manufacturing method. Fabrication of the agitators using a thermoplastic resin such as a polyolefin (polyethylene or polypropylene) which can withstand organic solvents and caustic agents is desirable to allow their use in a broad range of chemical environments. For example, improved vortex-agitation may be desirable during many mixing procedures such as chemical dissolutions or precipitations, chemical extractions, and biochemical denaturations with organic solvents and caustic agents including but not limited to alcohols, ketones, ethers, alkanes, aromatic solvents, chlorinated hydrocarbon solvents, strong acids, and alkaline reagents. It is also preferred that the vortex agitators withstand either sterilization by steam-autoclaving at a temperature of approximately 121° C., gamma ray irradiation, or exposure to a biocidal gas such as nitrous oxide. In this regard, commercially available grades of polypropylene can withstand each of these sterilization methods. Fabrication utilizing a thermoplastic resin such as polymethacrylate or polycarbonate which is more dense than water may be sometimes preferred over a polyolefin (typical density=0.9). For example, when vortexing an aqueous sample whose depth is similar to or greater than the height of the agitator, use of the denser resin allows the agitator to sink and agitate the bottom of the aqueous solution.
The present invention features an improved method for vortexing a liquid sample. The method includes providing a mixing implement or agitator device as described above; placing the implement in an appropriate vessel, e.g., a microtube, together with a sample to be vortexed; sealing the vessel with an appropriate lid or other closure if available; and subjecting the vessel, mixing implement, and sample to vortexing using a suitable gyro-rotary machine.
The length and cross-sectional shape of the vortex agitator alter the dynamics of liquid mixing within the microtube. As explained above, during vigorous vortexing of a microtube, a vortex agitator rod tends to move upward along its longitudinal axis to the top of the microtube. The maximum distance the rod can rise above the bottom of the microtube is determined by the difference in length between the rod and the inside height of the microtube. Upward and downward axial movement of the agitator, coupled with its rapid rotation and precession in the tube during liquid vortexing helps in dislodging pellets and resuspending or dissolving other solids in the microtube. With consideration to the geometry of the agitator rod, both round, triangular, square, and polygon cross-sections appear to be valuable alternatives. Agitators with angular corners appear to be especially useful in dislodging materials which are attached to the sidewalls of vessels. Agitator lengths ranging between approximately one-half and two-thirds the inner height of the sealed microtube appear to be particularly useful. Substantially shorter vortex agitators may be less useful for mixing, particularly when such agitators tend to be propelled to the top of the microtube where they are ineffective in dislodging pelleted material near the bottom of the tube. Likewise as previously pointed out, small spherical, ovoid, or block-shaped agitators tend to be propelled toward the top of the microtube during vortexing.
The presently described vortex agitator physically scrapes the inner sidewall of a container and perturbs simple circular liquid flow during vortexing. Such perturbation causes chaotic liquid movement and improves overall liquid mixing. In contrast to a magnetic stirring bar which is generally disposed horizontally during use and is restricted to movement on the bottom surface of a container nearest the magnetic driver table, the vortex agitator however, is generally vertically disposed and moves throughout the entire column of liquid in the container. Furthermore, the vortex mixing implement maintains at least intermittent contact while vigorously scraping portions of the inner sidewall in both the lower and upper half of the vessel when a sample is vortexed to dislodge sedimented material in the vessel. Comparing the method of using and propelling the present vortex agitator with that of a conventional stirring rod, the agitator is untouched by any external device and may be maintained sterile during use. Furthermore, while the vortex agitator promotes extreme agitation of a liquid, and is propelled by applying a generally circular vortex force to a container, the conventional stirring rod is typically used to promote gentle mixing of substances in a test tube, is propelled by hand or machine contact, and may be difficult to maintain in sterile condition.
For removing a vortex agitator from a microtube following its use, Applicant has found that a straight pin (preferably having an easily grasped head), other sharp pointed object, or a hollow plastic straw may be conveniently used. The pin is pushed into the end of the agitator allowing it to be lifted out of the microtube. Remarkably however, during most sample manipulation procedures including centrifugation and liquid recovery, the vortex agitator need not be removed from the microtube. For example, we have shown that normal centrifugal pellet formation occurs (on the lower sidewall of the microtube), and normal centrifugal liquid phase separation proceeds while the vortex agitator present in the microtube. The rod or straight wand-shaped agitator tends to bridge above the forming pellet during centrifugation, so that the disturbance of the pellet is absent, or at least minimized, during subsequent agitator removal or other manipulations.
Research into the unit cost for domestic production of the above-described polyolefin vortex agitators in commercial quantities (using the extrusion method for manufacturing) shows that they are cost-effective, i.e., less than one-half cent each. This modest cost will allow them to be used once and discarded if appropriate.
Other features and embodiments are within the following claims. | A method for improving the efficacy of vortex-mixing a liquid sample, in which a mixing implement and the sample are placed inside a microcentrifuge tube or sample vessel. The presence of the upright mixing implement in the tube or vessel does not substantially interfere with centrifugal fractionation of the sample. The method includes the steps of providing a rod or straight wand-shaped mixing implement, in which the length of the mixing implement is greater than the maximum inner diameter of the vessel but less than the maximum inner height of the vessel when sealed so that the mixing implement is constrained to remain substantially upright within the vessel. The surface of the mixing implement is configured and arranged to be free of any substantial depressions and concave blemishes which could trap sedimenting solid material in the sample during centrifugation. The sample and mixing implement are placed in the vessel, and the vessel positioned in a holder and/or adapter element of a vortex-mixing machine. Vortex-mixing is commenced and the mixing implement moves and/or gyro-rotates rapidly around the inner sidewall of the vessel thereby accelerating the mixing process. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wavelength selective optical device used in the optical communication field or the like. More particularly, the present invention relates to a wavelength selective optical device employing an optical filter as a wavelength selecting element, and a method of tuning the same.
2. Related Art
In the optical communication field or the like, there are known various devices utilizing the nature of the wavelength of light for controlling transmission and transferring of information. For example, the wavelength division multiplexing large-capacity optical communication (Dense Wavelength Division Multiplexing (DWDM), Coarse Wavelength Division Multiplexing (CWDM), or the like) in which multi-wavelength laser beams with a narrow line width are superposed at a high density and then input/output into/from one optical fiber is now spreading. In this wavelength division multiplexing optical communication, a desired wavelength signal (channel) must be demultiplexed from the multiplexed light signals or conversely multiplexed to such multiplexed light signals to bundle them into one optical fiber.
The center wavelength and the wavelength width of each channel are normalized respectively. The optical coupler constituting the system must select only a desired channel signal and pick up it at a low loss, and must prevent crosstalks of unselected signals between its adjacent channels and its outside channels.
In the high-density wavelength division multiplexing system such as DWDM, CWDM, or the like utilizing the dielectric multilayer optical filter as the wavelength isolating element, it is normal that, in order to enhance the isolation between the picked-up signals and reduce the crosstalk between them, the light transmitted through the filter is used to select the signal and also the reflected light including the residual reflection is treated as the express signal for the optical coupler on the subsequent stage.
As the optical filter, various optical filters such as a bandpass filter (BPF) for passing only a predetermined wavelength band, a shortwave pass filter (SWPF) for passing only a shorter wavelength side than the predetermined wavelength, a longwave pass filter (LWPF) for passing only a longer wavelength side than the predetermined wavelength, etc. are present in compliance with the applications. Normally, BPF is used in DWDM or CWDM.
Here, of importance are (1) both-side wavelength edges of the pass wavelength band of BPF are positioned on the outside of the wavelengths on both ends of the selected channel, and a signal loss in all wavelength bands in the channel is small, and (2) both-side wavelength edges are positioned such that the pass wavelength band of BPF does not contain wavelength bands of adjacent unselected channels, and crosstalks of unselected channels are suppressed sufficiently small.
Characteristics of BPF such as the wavelength bandwidth, the crosstalk blocking amount (isolation), etc. are decided substantially by the filter design. However, values of the filter such as the edge wavelength, the center wavelength, etc. are varied every lot at the time of filter production. Also, these values are varied to some extent in a sheet of glass substrate. For this reason, an amount of wavelength shift must be tuned (the wavelength tuning must be applied) consciously at the time of assembling the optical coupler to make the optical coupler conform to the standard of the optical system (component) using this optical coupler as the constituent element.
For example, in the case of 100 GHz DWDM system, a channel interval is about 0.8 nm and a channel bandwidth is about 0.22 nm. Therefore, it is possible that the performance characteristic of the component is largely affected even by a small wavelength deviation such as about 0.1 nm.
FIG. 1 shows a concept to tune the center wavelength of BPF. Assume that, when an incident light is incident on the BPF manufactured based on predetermined design values in compliance with a predetermined method, the passing characteristic of BPF, illustrated by light intensity P, is given as indicated by a broken line. This indicates that the center wavelength is deviated from a center wavelength λp of the specified channel (x) to the longer wavelength side and that a loss is increased on the shorter wavelength side than the channel bandwidth of the channel (x) to be selected. Also, the crosstalk in the unselected channel (x+1) on the longer wavelength side is increased. Therefore, the wavelength tuning must be applied to this characteristic as indicated by a solid line by any method.
Meanwhile, in the dielectric multilayer optical filter having the wavelength selectivity, when an incident angle of an incident light is changed, the wavelength edge is changed, or the center wavelength of the pass band together with the wavelength edge, if the filter is BPF, is changed. Normally the center wavelength is shifted to the shorter wavelength side by the oblique incidence in contrast to the vertical incidence. Consequently, it is feasible to execute the above wavelength tuning by utilizing this phenomenon.
FIG. 2 is a sectional view showing a basic structure of the wavelength division multiplexing optical coupler using a graded index rod lens. This optical coupler is assembled by optically tuning/fixing a subassembly, which is constructed by pasting an optical filter chip 40 onto a lens surface 33 of a dual fiber collimator 20 , and a single fiber collimator 110 . This dual fiber collimator 20 consists of a dual optical fiber pigtail 21 and a graded index rod lens 31 . This single fiber collimator 10 consists of a single optical fiber pigtail 22 (dual optical fiber pigtail may also be employed) and a graded index rod lens 32 .
An emitted light from one optical fiber 23 is incident on one end surface of the graded index rod lens 31 . Assume that a lens length of the rod lens is a 0.25 pitch (¼ of a ray sinusoidal wave path period (pitch) peculiar to the graded index rod lens), an emitted light from the rod lens 31 is collimated into a parallel light beam. Then, a light contained in this parallel light beam in a predetermined wavelength range is reflected by the optical filter 40 , then is converged again by the rod lens 31 , and then is coupled to another optical fiber 24 .
Also, a light other than lights in a light reflecting wavelength range is transmitted through the optical filter 40 , then is converged by the rod lens 32 of the single fiber collimator 10 , and then is coupled to the optical fiber 25 . The signal light is wavelength-separated via such optical paths to reflect the optical characteristics of the filter.
As the prior art associated with the wavelength tuning of the filter, in U.S. Pat. No. 5,799,121, for example, the technology of changing the incident angle of the light into the optical filter by changing an alignment interval of two optical fibers to tune the center wavelength is set forth. In other words, an incident position of the light into the rod lens 31 is changed by changing a distance (an offset amount of the optical fiber, see FIG. 2 ) d between an optical axis of the pigtail 21 and optical axes of the optical fibers 23 , 24 , and thus the incident angle (φ) into the optical filter 40 is changed. When an optical fiber interval 2d (normally two optical fibers 23 , 24 are arranged at an equal distance from the optical axis of the rod lens 31 ) is increased, the center wavelength of the selected signal is shifted to the shorter wavelength side.
Similarly, in U.S. Pat. No. 6,084,994, a mode of so-called dual optical fiber pigtail is constructed by fixing two optical fibers in the holder at a predetermined interval to actually suit the production of the optical coupler. Since the incident angle of the light into the optical filter can be changed by changing the interval between the optical axes of the optical fibers by exchanging the holder, it is possible to tune the center wavelength.
In the above method of tuning the selected center wavelength by adjusting the core interval of two optical fibers, there existed problems described in the following.
A core interval of two optical fibers becomes minimum when two optical fibers are tightly contacted to each other in parallel. A lower limit value of the core interval is defined by the cladding diameter (normally 125 μm) of the optical fiber. Since a finite effective diameter (a diameter which functions as the lens) exists in the rod lens, an upper limit value of the core interval is restricted by this diameter. Therefore, it is impossible to tune the selected center wavelength over the sufficient range.
Also, it is normal that the above holder is employed as the practical optical fiber fixing method. Normally the capillary in which through holes, through which the optical fiber is inserted respectively, are opened along the axis of the cylindrical member is employed as this holder. However, since an interval between the throughholes is small particularly near the above lower limit value of the core interval, it is difficult to open two through holes while maintaining the core interval at a desired value.
SUMMARY OF THE INVENTION
The present invention has been made to overcome such problems, and it is an object of the present invention to provide a wavelength selective optical device such as a wavelength division multiplexing optical coupler capable of carrying out a wavelength tuning with high precision without constraints on a cladding diameter of an optical fiber and an effective diameter of a rod lens.
A wavelength selective optical device of the present invention is applied to the optical coupler having a following configuration. The divergent light that propagates optical signals having a plurality of multiplexed wavelengths is incident on a first end surface of a first graded index rod lens, and then a parallel light beam being picked up from a second end surface of the first graded index rod lens is incident on an optical filter being arranged to face to the second end surface of the first graded index rod lens.
Then, a light being emitted from the first graded index rod lens and then reflected or transmitted by the optical filter is incident again on the second end surface of the first graded index rod lens.
It is preferable that the divergent light emitted from an end surface of a first optical fiber is incident on the first end surface of the first graded index lens. The light reflected by the optical filter may be coupled to a second optical filter though the rod lens.
In the wavelength selective optical device having the above configuration, a refractive index distribution constant of the first graded index rod lens is set in such a manner that a representative wavelength of a wavelength band of the light being reflected or transmitted by the optical filter is positioned within a desired range.
A refractive index profile N(r) of the graded index rod lens in the radius (r) direction can be approximated by the following formula:
N ( r )= No {1−((√{square root over ( )} A ) 2 /2) r 2 }
where √{square root over ( )}A is a refractive index distribution constant. Although the core interval of the optical fiber is still fixed, an angle of an emitted light from the rod lens, i.e., an angle of the incident light incident on the optical filter, can be changed by changing √{square root over ( )}A. Therefore, adjustment of changing the core interval of two optical fibers can be eliminated, and thus there is no necessity for preparing a number of capillaries having different through-hole intervals to change the core interval. In other words, the limitation imposed by the core interval can be overcome and therefore the wavelength selective optical device in which the center wavelength is tuned precisely can be provided readily.
Also, it is preferable that a light being passed through the optical filter should be incident on a first end surface of a second graded index rod lens being arranged such that the first end surface of the second graded index rod lens is faced to the optical filter, and a light being emitted from a second end surface opposed should be coupled to a third optical fiber.
If the reflect wavelength band is tuned precisely as described above, the pass wavelength band is similarly tuned. As a result, the wavelength selective optical device utilizing the reflected light and the transmitted light can be provided readily.
Also, it is preferable that the above optical filter should be formed directly on the second end surface of the first graded index rod lens. If the dielectric multi-layered film constituting the optical filter is forming simultaneously and directly on a number of rod lenses each having the different √{square root over ( )}A, the wavelength selective optical devices having various center wavelengths can be provided readily.
Alternately, it is preferable that a cylindrical member having an inner diameter through which the first graded index rod lens can be slid without clearance should be prepared, then an optical filter chip in which the optical filter is provided should be pasted to one end portion of the cylindrical member, and then the first graded index rod lens should be inserted from the other end portion of the cylindrical member.
According to this configuration, if a number of rod lenses each having the different √{square root over ( )}A and the identical outer diameter are exchanged, the wavelength selective optical device having the desired center wavelength can be provided readily.
In other words, it is preferable that the first graded index rod lens should be selected among a plurality of graded index rod lens groups having various different refractive index distribution constants such that the center wavelength of the transmitted light from the optical filter or the reflected light by the optical filter is positioned within a desired range.
Upon assembling the wavelength selective optical device of the present invention, a light in a wavelength range that an optical filter separates (namely reflects) is incident on the rod lens from one optical fiber of the above dual optical fiber pigtail, and then a light being reflected by the optical fiber is coupled to other optical fiber by the rod lens. Then, relative positions of the rod lens and the dual optical fiber pigtail are moved and fixed such that an intensity of the coupled light is maximized or exceeds a predetermined value. Then, a representative value, e.g., a center value, of the separated wavelength band of the wavelength selective optical device is tuned within a predetermined range by exchanging the rod lens being incorporated for the first time for another rod lens having a different refractive index distribution constant.
If such wavelength characteristic tuning method is adopted, the wavelength selecting characteristic of the wavelength selective optical device can be tuned to a predetermined value without change of the interval between the optical fibers.
According to the present invention, even though an optical fiber whose center wavelength is deviated from a target center wavelength is manufactured, the optical fiber that is able to operate properly without correction of a core interval of two optical fibers can be manufactured. As a result, yield of an assembling production including the production step of the optical filter can be improved largely.
Incidentally, the optical filter of the invention is not limited to a band pass filter for a specific wavelength band. Other optical filters defining various wavelength ranges such as shortwave pass filters (SWPF), longwave pass filters and the like are also applicable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a conceptual view showing a pass band spectrum of an optical filter (BPF) and its center wavelength tuning;
FIG. 2 is a schematic sectional view showing a wavelength division multiplexing optical coupler using a graded index rod lens;
FIGS. 3A and 3B are schematic sectional views showing examples of wavelength division multiplexing optical couplers of the present invention, wherein FIG. 3A shows the case where a refractive index distribution constant (√{square root over ( )}A) of the graded index rod lens is small, and FIG. 3B shows the case where the same is large; and
FIGS. 4A and 4B is views showing another example of the wavelength division multiplexing optical coupler of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Suppose that a refractive index profile N(r) of the graded index rod lens in a radius r direction can be represented by the formula:
N ( r )= No {1−((√{square root over ( )} A ) 2 /2) r 2 }
where No is a refractive index of the rod lens on the center axis, and √{square root over ( )}A is a refractive index distribution constant. When the rod lens a lens length of which is equal to a 0.25 pitch (¼ period of the ray sinusoidal wave path period) is employed, a relationship between a position r 1 of an incident light incident vertically on one end surface of the rod lens and an angle θ2 (unit: radian) of an emitted light emitted from the other end of the rod lens is represented by the following formula:
θ2 =−No√{square root over ( )}A·r 1
Therefore, the angle θ2 is in proportion to √{square root over ( )}A when the position r 1 of the incident light is set constant. More particularly, if adjustment is applied to √{square root over ( )}A of the rod lens, the angle of the emitted light from the rod lens can be adjusted even though the core interval (2d) in the optical fiber pigtail is still fixed as it is (the incident position of the incident light is not changed), and therefore the angle of the incident light incident on the optical filter can be adjusted. If the rod lens having the large √{square root over ( )}A is employed, the propagated light is bent sharply and thus the larger angle of the incident light can be derived. Accordingly, the selected wavelength is shifted to the shorter wavelength side.
Upon manufacturing the optical coupler that is assembled by tuning/fixing optically a subassembly in which an optical filter chip is fixed near a lens end surface of a dual fiber collimator, which consists of a dual (or more) optical fiber pigtail and a graded index rod lens, and a single fiber collimator consisting of a single (or more) optical fiber pigtail and a rod lens, the center wavelength in the bandwidth of the transmitted light or the reflected light of the optical filter is tuned arbitrarily while exchanging the rod lens having the different refractive index distribution constant (√{square root over ( )}A).
In particular, if the rod lens having a 0.25 pitch is employed, the optical fiber pigtail and the optical fiber can be adhered/fixed onto respective lens surfaces. Adjustments of the composition of the glass base material, the diameter of the glass base material, ion exchange conditions, etc. make it possible to adjust the refractive index profile of the graded index rod lens successively, precisely and easily.
Also, in the rod lens in which the optical filter is formed directly on the lens end surface, the refractive index distribution constant can be readjusted by annealing the lens in the temperature range in which an ion mobility is increased.
EXAMPLES
A method of constructing the wavelength division multiplexing optical coupler while applying the wavelength tuning will be explained in detail with reference to the drawings hereinafter. In Figures, the same members are indicated by affixing the same reference numerals to them.
A first example is a wavelength division multiplexing optical coupler whose target center wavelength in the selected wavelength bandwidth is set to 1550.12 nm.
The dielectric multilayer BPF whose pass bandwidth is designed to 0.3 nm was formed on a glass substrate. As shown in FIG. 3A , this BPF chip 140 was bonded/fixed onto an emitted side end surface (second end surface) 133 of a graded index rod lens (first graded index rod lens) 131 , a refractive index distribution constant (√{square root over ( )}A) of which is 0.326 mm −1 and a lens length of which is a 0.25 pitch, by using a jig.
It is desired that, in order to prevent the incident light from returning to the optical fiber, an incident side end surface (first end surface) 135 of the rod lens 131 should be formed to incline against a center axis 137 of the rod lens 131 . A dual optical fiber pigtail 121 was arranged to face to this end surface 135 , and a position of this pigtail was adjusted. In this case, two optical fibers 123 , 124 were composed of a normal single-mode optical fiber having a cladding diameter of 125 μm respectively, and the core interval was set to 125 μm by adhering closely two optical fibers.
In the core tuning operation, a laser beam having a wavelength, which is in a wavelength 1.55 μm band and is out of the pass wavelength of the optical filter 140 , was input from one optical fiber (first optical fiber) 123 . This light was reflected by the optical filter 140 , then passed through the rod lens 131 , and then emitted from the end surface 135 . Positions of the rod lens 131 and the optical fiber pigtail 121 were relatively moved and adjusted such that a quantity of light obtained when this light is coupled to the optical fiber (second optical fiber) 124 is maximized.
After the core tuning was completed, the wavelength of the laser beam was swept over 5 nm and the pass wavelength spectrum was measured. As a result, the measured center wavelength was 1550.44 nm in contrast to the target center wavelength of 1550.12 nm. Therefore, as shown in FIG. 3B , when the rod lens 131 was replaced with another graded index rod lens 231 having √{square root over ( )}A=0.418 mm −1 and then their positions were retuned, the spectrum having the center wavelength of 1550.09 nm was obtained. Then, a dual collimator was completed by adhering/fixing the rod lens 231 and the dual optical fiber pigtail 121 with the epoxy resin.
Since √{square root over ( )}A of the rod lens was adjusted to increase by about 28%, the wavelength tuning for shifting the center wavelength of the filter toward the shorter wavelength side by 0.35 nm could be implemented. Assume that the wavelength tuning generated per 1% of √{square root over ( )}A change is defined as a tuning factor, the tuning factor at this time corresponds to −0.0125 nm/%.
After the dual collimator with the optical fiber was completed, positions of a single optical fiber pigtail 122 and a graded index rod lens (second graded index rod lens) 132 constituting a single optical fiber collimator were adjusted in such a way that a quantity of light of the light that is passed through the optical filter 140 and then coupled to the single optical fiber collimator is maximized. Then, the pigtail 122 and the rod lens 132 were adhered/fixed with the epoxy resin. As a result, a 3-port optical coupler was completed.
When a spectrum of the light that is passed through the optical filter 140 and then coupled to an optical fiber (third optical fiber) 125 was measured, the pass wavelength band and the stop wavelength band were just reversed from those of the previously-measured reflected light of the optical fiber, nevertheless the center wavelength coincided precisely with that of the reflected light at 1550.09 nm.
In the above example, the optical filter fabricated on the glass substrate was employed. But the film of the optical filter can be formed directly on the end surface of the graded index rod lens. Normally, such direct film formation onto the end surface of the rod lens can be applied to a number of lenses at a time. Therefore, the dielectric multi-layered film having the same film arrangement can be simultaneously formed on a wide variety of lenses each having the different √{square root over ( )}A.
Next, a second example having the similar characteristic to the above first example will be explained hereunder.
As shown in FIG. 4 , a BPF chip (optical filter) 340 having an outer dimension of 1.8 mm square and a pass bandwidth of 0.32 nm was adhered onto one end surface 352 of a glass tube (cylindrical member) 350 having an inner diameter of 1.81 mm, an outer diameter of 2.6 mm and a length of 2 mm. Then, a graded index rod lens (first graded index rod lens) 331 having an outer diameter of 1.80 mm and {square root over ( )}A=0.326 mm −1 was inserted securely into the glass tube 350 so as to contact the BPF chip 340 . Then, like the first example, the dual optical fiber pigtail 121 having the core interval of 125 μm was faced to an end surface (first end surface) 335 of the rod lens 331 , which was directed to the opposite side to an end surface 333 that contacts the BPF chip 340 . Then, the position of the optical fiber pigtail 121 was adjusted with respect to the rod lens 331 .
In contrast to the target center wavelength of 1550.12 nm, the actual value measured based on a spectrum of the reflected light from the optical filter 340 was 1549.98 nm. Therefore, when the rod lens 331 was replaced with a rod lens having √{square root over ( )}A=0.302 mm −1 and then their positions were retuned, a spectrum having the center wavelength of 1550.07 nm was obtained at this time.
This operation merely yielded the insufficient adjustment yet. Hence, when this rod lens was pulled out from the glass tube 350 , then another rod lens 331 having √{square root over ( )}A=0.289 mm −1 was inserted to contact tightly, and then the position of the optical fiber pigtail 121 was retuned, the center wavelength of 1550.12 nm was obtained and coincided perfectly with the target value. Then, the glass tube 350 and the rod lens 331 , and the end surface 335 that is on the opposite side to the optical filter 340 and the dual optical fiber pigtail 121 were fixed with the epoxy adhesives respectively, whereby a dual fiber collimator with the optical filter was completed. Since the single fiber collimator for receiving the transmitted light from the optical filter is similar to that in the first example, its explanation and illustration will be omitted herein. In this example, the tuning factor was consistent with −0.0125 nm/%.
From only above two examples, it was verified that, if the refractive index distribution constant (√{square root over ( )}A) of the rod lens is changed from 0.289 to 0.418, for example, the center wavelength of BPF can be tuned by 0.46 nm.
In the above examples, the optical coupler for isolating the signal on one selected channel from the incident signals by tuning the center wavelength of BPF is explained. But the present invention can also be applied to other optical parts.
Also, there is the case where not the above selection of one channel but the selection of plural channels is required. In this case, the edge filter, i.e., SWPF or LWPF is employed. Because this wavelength edge must be adjusted with precision of several nm or less, the present invention can also be applied.
Further, in the optical add-drop module, or the like, for example, plural optical filters are employed and the optical fiber has three ports or more. Because the wavelength standard of the selected channel group is similar to the above, the present invention can also be applied in tuning these wavelength edges.
The described embodiments are directed to the optical wavelength division multiplexing optical couplers used in the wavelength division multiplexing optical communication where plural discrete wavelength optical signals are multiplexed. However, the invention is applicable to other wavelength selective optical devices.
For example, gains of an erbium-doped optical fiber (EDFA), which is generally used for amplifying attenuated propagated light in an optical fiber, have wavelength dependency. A gain flatten filter is used for flattening the gain change in the wavelength. It is necessary to adjust the wavelength dependency of the gain flatten filter for accomplishing accurate gain flattening. Thus, the invention is suitably applied to such the EDFA.
Input light to the rod lens is not limited to a light having discrete wave length in the invention. The invention is applicable for picking up a part of input light having continuous spectrum. For example, for picking up a narrower wavelength band from a broader wavelength band of light emitted from a super luminescent diode or the like. In this case, light emitted from the light source is directly incident on the graded index rod lens, and a light beam of reflected light or transmitted light by the filter is picked up. The invention is suitably applied for accurately selecting the wavelength of the light beam. Similarly, the invention is applicable in the case that a narrower wavelength band is picked up from an amplified spontaneous emission (ASE) light emitted from the EDFA.
The light beam is not always coupled to an optical fiber. The reflected light or the transmitted light by the optical filter may be input to a photodetector and converted to an electric signal.
For the optical filter of the invention, a multi-layered optical interference filter is used. A desired optical properties can be obtained by designing refractive index and film thickness of each layer constituted by dielectric material or the like, in other words, by designing the periodic structure of optical film thickness.
As representative examples, there are known a band pass filter having optical characteristics as shown in FIG. 1 that a predetermined wavelength band of light is passed and other wavelength of light is reflected, and an edge pass filter having optical characteristics that a wavelength range larger than (or smaller than) a predetermined wavelength is passed and the other range is reflected.
Further, by combining such an optical filter, it is possible to realize a gain flattening filter changing the transmitting rate dependent on the wavelength in which the gain of the optical fiber amplifier is flattened. In the invention, a reference wavelength related to the optical characteristics of various filters can be adjusted. For example, the representative wavelength is the center wavelength for the band pass filter, and is the wavelength at which the transmitting rate is 50% for the edge pass filter. | The invention provides a wavelength selective optical device in which a light emitted from an end surface of a first optical fiber that propagates optical signals with a plurality of multiplexed wavelengths is incident on a first end surface of a first graded index rod lens, then a parallel light beam emitted from a second end surface of the first graded index rod lens is incident on an optical filter arranged to face to the second end surface of the first graded index rod lens, and then a light reflected by the optical filter is incident again on the second end surface of the first graded index rod lens so as to couple to a second optical fiber arranged on a first end surface side of the first graded index rod lens, wherein a refractive index distribution constant of the first graded index rod lens is set such that a center wavelength of the light reflected by the optical filter is positioned within a desired range. | 6 |
FIELD OF THE INVENTION
[0001] The various game inventions disclosed herein relate to methods and apparatus of providing a game, primarily word games, and various optional methods and apparatus for implementation. The inventions further relate to new and improved, primarily word games, involving at least one player participation preferably, in a main embodiment format, in a game show staged environment, but also in Interactive Internet Player Formats such as Wheel of Fortune®, Jeopardy® and Family Feud®, et al. The game has play qualities like Who Wants to Be a Millionaire® and Let's Make a Deal®, et al. that may be formatted and distributed to audiences in broadcast mediums, such as television game shows.
[0002] These present game shows, like the present inventions being disclosed herein, are also highly suitable to be played competitively or watched in or on other communication medium, readily adapted and formatted to be played over the internet or other communications networks, such as smart phones and many other “cloud-connected” or internet devices in what is commonly referred to as the “Internet of Things” or IoT. Games may be played under many formats including, for example, TV game shows, interactive electronic games, and board games. Interactive electronic games are played on a wide variety of devices, as game machines, e.g., Nintendo, Sony PlayStation®, Game Boys® and Palm Pilots, Microsoft X-box, GameCube, and personal computers, and on-line formats.
BACKGROUND OF THE INVENTION
[0003] There are a plethora of game shows that have been introduced to both the USA and world market over the years primarily by way of television. Many of these are based upon previous printed, old popular, as Hangman or Tic Tac Toe or game board-played type games that have been around for decades, such as crossword puzzles, Scrabble®, and various anagram, acrostic, vocabulary, spelling and word search games. As well there are board games like Scattergories® and Pictionary® et al, that are typically played in a group setting and have as of yet, not been made acceptably adaptable to a TV game show format.
[0004] Television game shows, such as Wheel of Fortune® (which is the simple yet tried and tested game of “hangman” adapted and combined with chance wheel), Jeopardy and Family Feud, as well as games like Who Wants to Be a Millionaire®, Let's Make a Deal®, and Are You Smarter than a Fifth Grader?®, et al, are games that have, to one degree or another, stood the test of time because of their inherent qualities of likeability, ease of play for both contestant and audience, chance and excitement, as well as highly esteemed show hosts.
[0005] The amazing fact according to the book entitled: “The Encyclopedia of Game Shows, 3rd Edition, Checkmark Books, Copyright ©, 1999”, that as of 1999, there are over 500 games that have had at least one pilot run on TV. However, nearly all of these games though are not televised today. It remains evident that only a few of these games listed in the book survived more than one pilot season, or even single showing. Only a few, in addition to the time tested games listed above, have had any significant longevity on TV or in the internet world.
[0006] Consequently, newly invented game modules and the variously potentially formatted modifications of a unified game that these modules may be integrated into, like those disclosed in the present embodiments and inventions herein, in order to be successful and have any lasting duration, have to meet even higher criteria for the game players and audiences who make them popular. Not only does any new game or game show, in order to be long-lived and “successful” have to fit well into a highly competitive present environment, where air time and distribution opportunity on TV stations, especially, prime time, is nearly impossible to secure, there is also the whole new dynamic of “likeability” and “ease of play and “ubiquity of device play” criteria that a new game must meet. It is essential that a potentially successful game must be able to be played seamlessly, not only on broadcast TV, but also over a vast and increasing array of internet, interactive environments.
[0007] This is why it is important to note that these present successful and long-lived game shows discussed above, like the present inventions being disclosed herein attempt to achieve, are also highly suitable to be played competitively or watched in or on other communication mediums, such as having an “app” for home audiences to play along during live broadcasts, readily adapted and formatted to be played over the internet or other communications networks, such as smart phones and many other “cloud-connected” devices in what is commonly referred to as the “Internet of Things” or IoT.
[0008] By the year 2020, it is estimated that there will exist more than 50 billion devices connected to the Internet of Things, which is the term used to describe the collective devices that are computerized devices, actively connected or linked to the internet. The inventions disclosed herein intend to fully use not only the standard computer and TV game show model, as well as all other computer type devices that are tried and tested and standing as a strong medium of enabling people to both watch and participate in the present game invention, but also be connected and playable from any number of devices connected the IoT medium, as well.
[0009] However, irrespective of the new dynamics of adapting a novel game invention to the said IoT, the authors, Schwartz, Ryan and Wostbrock, of the above sited book, “The Encyclopedia of Game Shows, 3rd Edition, Checkmark Books, Copyright 0, 1999,” reveal also on page 22 of their forward suggestions why certain game shows become popular: “Perhaps it is the fantasy of being a winner or identifying with the pressure and excitement of the moment. Could it be the parade of ordinary everyday people that grace the small screen to entertain us? Maybe it's the dream of instant riches. Or, the ability to participate in an entertaining manner from our own armchairs. Whatever the conclusion, it goes without saying that we love the . . . Surprises, Tension, Energy, Voracity, Excitement, Riches, Yippies, Academia and Nonsense.”
[0010] One may add to this candid quote the power and personableness or personality of the host, for example, such as the highly successful and well-liked Wheel of Fortune show host, Pat Sajak and the friendly humor elements he has added to the TV game show industry. TV audience and other audience participation in real time is another factor that has become more relevant and important with the advent of the IoT, as mentioned above. These all are present objectives, one by one, that the present invention seeks to improve upon and expand.
[0011] In the present inventions, as well, the intrigue of themes that are progressively revealed, as well as providing a collection of usable tokens or letters/information gained throughout play that may be used to contestant advantage in latter parts of game play are just some of the other objectives and elements that the present inventions desire to introduce, while enhancing many of the other reasons enumerated above by the authors as to why certain games are enjoyed and made popularly enduring by audiences.
[0012] Though the present long-lived game shows, such as those listed above and others, have had a lengthy and prosperous reign and TV and internet dominance, it is believed, and thus it is a further object of the present inventions, that even these legendary games have shortcomings that may be improved upon by other quite diversely structured and functionally different methods of play and game settings and strategy, as the steps and components of the present invention attempt to, as are further objects of the invention, provide novel and improved games, game methods, game strategy, game contestant and audience interaction, novel game components, and game flow and pace, more exciting and challenging game structure, and more intense audience desire for participation, many of themselves becoming the next generation of game players. These are several, but only some of the objectives and of which will be understood more in the following further background discussion.
[0013] A Geography game show patent, U.S. Pat. No. 7,244,180, discloses a geography game show that seeks answers to questions related to geography provided within an allotted time period qualify participants for monetary or material rewards, together with learning credits. Provision is made in the show to allow real time participation of contestants or competitors, live show audience participants and remote TV viewers having Internet connections. An interesting educational feature provides for learning credits through the game play that may be converted to college credits by taking appropriate validation tests from accredited educational institutions that have made arrangements with the geography game show. The responses of contestants or competitors, live show audience participants and remote TV viewers, as well as the rewards and the leaning credits, are electronically processed and appropriate credits are issued using print outs or magnetic media.
[0014] Though a highly useful game, at least a couple limiting features of this game include a “one note” theme—Geography—and not a significant in the way of, game diversity, intrigue to and surprise. This is a highly effective learning and educational tool, however, especially with its emphasis on interactive and live audience participation.
[0015] The following two patents cover early intellectual property of “word-association” games, the first being found in U.S. Pat. No. 3,606,336, wherein a player starts to make a word beginning with a selected letter that is obtained through a chance means. The letter also has a chance selected number of letters using lettered playing pieces available to the first player. A second player builds a second word at right angles to the first word using lettered playing pieces available to the second player, the initial letter of the second word being the last letter of the first word. A unifying theme is that each of the words formed must have an associated thought suggestion with the preceding word. Though useful and enjoying, this game has limited scope of game play, unlike the present invention.
[0016] U.S. Pat. No. 4,928,976 discloses a word association game in which a player selects a “play word” from a list included in the game. Each player then receives a category selected by chance. The players must then provide words falling within said category; the first letters need to start with the letters of the “play word”.
[0017] Many other word related games such as crosswords and Scrabble® are well known in the art, including these patents immediately above.
[0018] Application WO 2008117084 A1 also discloses a word association game in which a player must reach a target word from multiple source or start words by finding a word common to both the target and source words or link words with a plurality of link word option fields, at least one of which comprises a plurality of link words. A certain amount of link words link to said start word to said target word; said start word has associated with it a predetermined first link words in said plurality of link word option fields. A player must find a word common to three provided words (i.e. one target word and two source words). The player is aided by the provision of supporting clues in the form of sentences.
[0019] An internet game show in which visual clue is progressively exposed to contestants or competitors disclosed in U.S. Pat. No. 6,935,945 B2. The clue is obtained through a program running on a server, is given to contestant and that clue is related to a textual answer. The contestant selects the portions of the visual clue to be exposed. The entire visual clue is loaded onto each of the contestants or competitors' computers prior to the beginning of each game, and the contestants or competitors' game software progressively exposes the visual clue.
[0020] Because contestants or competitors fill in a series of blanks with the answer and activate a send button, there is opportunity for the contestants or competitors to have their “heads downward” and not interacting with the audience. Note: This relates to one of the further objectives of the present invention, in that it unlike the above patent, it is desired that nearly all but the most essential minimum time of play will the contestants or competitors not be verbally engaging and being engaged by the show host or audience, at least in the traditional “TV Game Show format.” In other words, writing down answers is not an objective of the present invention disclosed herein—precisely the opposite, so as to engage all audiences.
[0021] Unlike the present invention, if this internet only participation component was the only modus operandi of U.S. Pat. No. 6,935,945 B2 it would be fine for contestants or competitors at “home” game play, since contestants or competitors' game software sends the contestant's answer along with a time stamp indicating the time elapsed since the beginning of the internet game show. At the end of the internet game show, the game show host computer compares the times that the correct responses were sent. The correct response that contains the earliest send time is the winning response.
[0022] Another game show patent disclosed in U.S. Pat. No. 6,340,159 B1, titled: “Double Cross™.” Game Show and describes a method of playing a game that allows players to compete to complete a crossword puzzle. Again, here the game is limited to “Crossword Puzzles” and thus has limited variation, unlike the object of the present invention, which is to provide an almost limitless variation of potential “game modules.” The Double Cross game includes a game board which is configured as a grid of squares with a video screen in the center of the board which can be used to display written or visual clues to help solve the crossword puzzle. The players alternate controlling the selection of clues; when they answer a clue correctly they continue to control the selection, and when they answer incorrectly the clue selection passes to the next player. The intrigue the clues add in this game is very favorable to engage long term player and audience interest, and though very much unlike the present invention herein, which includes a different and arguably, equally engaging intrigue factor by using “Hot Letter” (further explained throughout), the clue elements of Double Cross are quite positive for game play.
[0023] Further, the game also allows players, having selected a clue, to “double cross” an opponent by challenging that opponent to answer the clue, exposing that opponent to the danger of losing some or all of his accumulated points. The game also includes a final phase where the leading player, or all of the players, must solve a word puzzle consisting of only two interlocking words. The game can be played on a television game show, using telephone or internet communication technologies, as a video game or on a board game.
[0024] U.S. Pat. No. 6,439,997, entitled: Television/Internet Game Show discloses a method for creating and providing information used in a television game show, where that information is obtained from the Internet.
[0025] Users must register and answer a questionnaire over the Internet, to create a user profile for each registered user. A fixed number of user profiles are randomly selected periodically, and then posted on the Internet. From these profiles, users then vote for their favorite user profile, and the winner is given a large monetary award, to be presented live during a television broadcast. The winner must spend the large monetary award within a fixed period of time, or else lose the unspent portion of the award. Sponsors will provide the large monetary award each week, and will be given a prominent advertisement that will be posted on the pertinent Internet web site at which the users register and vote.
[0026] This particular game would seem to lack a long term impetus to motivate an audience since there is really no significant challenge presented nor real skill sets to challenge the participants except for spending money within a certain time frame. The Price is Right™ game show at least requires a contestant to guess the nearest price of the prize to advance in the game.
[0027] “System and Method for Using a Game to Interact with Television Programs”, disclosed in: U.S. Pat. No. 8,360,885 B2 includes a computer-readable storage medium including instructions, and a computer-implemented method for obtaining votes for participants in a television program. Code for a game is transmitted to a computer system, where the game includes an in-game voting module that allows a player of the game to cast votes for participants in a television program.
[0028] This patent, as other discussed herein this background, demonstrates the direction of technology to allow votes to be managed and results disseminated through a voter-participating audience, as the present invention also envisions for its one of many methods of distribution and play.
[0029] An older interactive game technology patent U.S. Pat. No. 5,035,422, entitled: “Interactive Game Show and Method for Achieving Interactive Communication Therewith” illustrates the early perceived importance of interactive game play within the patent art of record, even at this time, phone modems were the method of operation for such audience or contestant interactivity
[0030] Individuals electronically select at least one possible outcome of a plurality of outcomes of a future event, and are able to participate in the outcome of that event and possible share in a prize award associated with the event. In the preferred embodiment, individuals forming the home audience of a televised game show are able to electronically communicate a series of random numbers using their telephones to participate in possible winning the prize awards of the show. In addition, both on-camera game participants and the studio audience also participate and have the ability to win prizes. Again, however, the novelty of the show experience and challenge are arguably limited in this game, the only focus being upon the mode of selecting the possible outcomes of an event, against another contestant, using electronic means connectivity.
[0031] U.S. Pat. No. 5,088,739 discloses a game with an environmental theme. The players work together with “crisis cards” to solve environmental crisis problems selected. There is a pie shaped game board with four pathways, wherein an area of the world is represented using three symbolic tokens. Spaces on the board represent land, water and sky. Movement is based on the rotation of a central globe with indicators pointing to different colors and eco-lottery cards. Sets of instructional cards are used and player movement is guided using eco-currency. The first player to reach the center of the board wins the game. Television video game is offered as one of the formats. Interactive players only are permitted to play in the game, with the result that game show live audiences or remote TV viewer audience are excluded from game participation.
[0032] As the present invention herein discloses a wheel, it also contemplates other “Chance mechanisms” to determine selective game play actions and game functions, and thus may use as well, a “Globe-type” rotating means with game indicia to just as well provides means for game play.
[0033] Another interactive game that may as well provide a format for a televised Game Show is entitled: Televised Competition Viewer Voting Modified Scoring Methodology, disclosed in a more recent U.S. Pat. No. 7,258,275 B1. The patent demonstrates methods for tabulating votes cast by audiences of “Reality TV” shows in which contestants or competitors are competing with each other. Votes from prior voting sessions are tabulated in addition to votes cast during the current voting session, resulting in a modified electronic voting tally. Such modified tally will place more importance on average voting results over several voting sessions and less importance on the current voting session, thereby placing greater emphasis on the consistency of each contestant's voting tallies and therefore the consistency of their performances from one show to the next. The purpose is that there would be a greater likelihood that the contestant with the greatest popularity with television viewers over the entire life of the series will be determined the ultimate winner of the television series contest.
[0034] In U.S. Pat. No. 7,440,919 a financial game that may be televised is disclosed entitled: “System and Method for a Financial Planning Competition” The abstract reveals a game that is a financial planning competition having at least two phases, an embodiment of the first phase including a written competition including providing a fictitious client profile to pre-selected teams, allowing each team to create a written financial plan based on the client profile and awarding a score. The second phase including giving high-scoring teams a revised client profile containing a change of facts to the original client profile allowing the teams to redraft the original financial plan, receiving an oral financial planning presentation from each team based upon the revised client profile for scoring and awarding a score. Any phase of the present invention may exist in a live environment or over a network, such as the Internet. The competition may also optionally include at least a third phase which is preferably styled, in one embodiment, as a game show format based on financial planning concepts. As in the present invention herein, the advantages of an “educational game” are many, as the above patent has significant ability to assist business learning principles in the area of financial planning and investments. In a similar, however, yet far broader way, the WordSmith Wars™ game herein can use not only word games in many variations, but even, as well, comprise other games, like mathematics, history, science etc., besides its focus on English and literature, grammar, etc. as a highly valuable educational tool.
[0035] Two following patent includes word related games closer in nature to the present invention. The first, Vocabulary word game U.S. Pat. No. 6,412,781 B1 A collection of playing pieces for a vocabulary word game is disclosed. The pieces contain on one face a multi-letter combination of at least two letters plus a designator indicating required location of the letter combination in words. During a playing interval one playing piece is displayed to all players. Each player writes a list of words containing the selected letter combination at the designated location in the words.
[0036] After a predetermined time limit the players reveal their list to all. The winner of the playing interval is the player with the greatest number of words on their list. The game continues for a chosen number of intervals, the game winner being the player winning the greatest number of individual playing intervals.
[0037] U.S. Pat. No. 6,322,074 B1 discloses a game device having several user-selectable cells extending between start and finish areas, where each of the cells is associated with a character performing an answer to a question or clue. These clues are given in the form of a category. One or more participants move from the start to the finish area by selecting cells whose characters form a valid answer as the contestants or competitors carefully step on them or physically identify them in proper sequence. Various correct answers or paths between the start and finish areas can exist. Though having an exciting potential for game play, since it is engaging the entire body of the contestants or competitors, unlike the present invention, the variation of game play that can “fit” into this type of format is somewhat limited as it would be impractical for such use.
[0038] A System and method for interactive contests game is disclosed in U.S. Pat. No. 7,162,433 B1 wherein the game provides for content review, distribution, ranking and access and creation and performance of contests among sets of content-based contestants or competitors. Interactive, ongoing, multi-level, multi-round contests with expert review of and filtered submission of content-based contestants or competitors. Among other advantages, providers may use the system and method to obtain expert and consumer review and ranking of their content.
[0039] The following additional game patents are not the applicant's summarizations, but for sake of repetition of content, are included and repeated herein and given credit to their author in this application. These summaries represent excellent summarizations of additional games the applicant would want described, as discussed by inventor Garnet McHugh, pages one to five in: Geography Game Show Patent, U.S. Pat. No. 7,244,180, and are hereby incorporated herein as relevant prior art to the present invention.
[0040] U.S. Pat. No. 5,108,115 to Berman et al. discloses an interactive game show and method for achieving interactive communication. Participants are able to electronically select a future outcome from a number of possibilities. The selection is made from a series of sets having two possible outcomes. Contests are won by selecting correct outcomes. A prize is shared when that outcome is realized. Home audience viewers can participate in a televised version of the game show, using telephones to communicate a series of random numbers. These random numbers effect the selection, which can lead to award of a prize. No disclosure is contained by the patent concerning a geography game show that provides an educational learning experience
[0041] U.S. Pat. No. 5,193,818 to Leeson discloses an entertainment game, suitable for a parlor game, a video game or a television game. The game comprises a plurality of distinct arbitrarily selectable information units with two independently viewable sub-units. The first sub-unit is a representation of a recognizable object and the second sub-unit comprises questions and answers concerning the object represented in the first sub-unit. At first the player needs to identify the recognizable object in the front of the card to be able to roll a dice. If he is successful, he gains 5 points. The rolled dice provides a number and the question on the second sub-unit corresponding to the rolled dice number is read. If the player answers that question correctly, he gains additional points and rolls the dice again. Dice rolling terminates when a player answers the question incorrectly, rolls a previously rolled number or runs out of all the questions. The game is adaptable for a video game or a television game show with the master of ceremonies asking the questions. No disclosure is contained therein concerning a geography game show that provides an educational learning experience.
[0042] U.S. Pat. No. 5,513,852 to Robinson discloses a time-to-win game. This intellectual challenge game requires at least two players. A first player is selected on the basis of a card draw, by selecting highest value card. The selected player is asked to pick a number from 1 to 12, thereby selecting a numbered disk that reveals a question category. Three questions are projected on a screen sequentially. If the selected player answers these questions correctly, his display clock will be advanced by 15 minutes and he will receive $50 for each correct answer. Next the host asks each of the players to provide an element common to these three questions. The contestant that buzzes first is permitted to answer the question. If he answers the question correctly, his clock is advanced by five minutes, and the player receives $50. Each incorrect answer results in loss of 5 minutes on the clock. The first player to advance his clock to the 12 o'clock position wins the game round, and advances to a bonus round where he is presented with 16 questions. If a player answers 12 questions correctly during a 2.5-minute time period, he wins a jackpot prize of $12,000. If the bonus round player does not answer 12 questions correctly during the 2.5-minute time period, he is paid $25 times the number of correct answers. The game disclosed by the '852 patent is not a geography game show that provides an educational learning experience.
[0043] U.S. Pat. No. 5,545,088 to Kravitz et al. discloses a television game interactively played by telephone with a television viewing home audience. A master board has numbers, which are selected by chance at random and represent a specified portion, for example, of the last two digits of telephone numbers for members of a home viewing audience. Each time a question is correctly answered by the game player, one of these numbers from the master board is validated by a square. This validated number is also placed on a five by five-game board with randomly selected numbers. When a line is filled in on the five by five-game card by correctly answered questions, it becomes part of a filled line which is horizontal, vertical or diagonal. The viewing audience can then call the television station or be pre-registered to win a prize. A game player and studio audience that are assigned to the game board also win prizes. The '088 patent does not disclose a geography game show that provides an educational learning experience.
[0044] U.S. Pat. No. 5,562,460 to Price discloses a visual educational aid. A tool is thereby provided to relate similarities and differences between different topics and relationships between subtopics and topics in a logical, orderly manner similar to continents, countries, states and features like rivers in a map. This logical ordering has similarities in appearance to a geographical map, but has no connection with a real geographical map. A map is merely used to display and order similarities and contrast dissimilarities. The patent discloses a logical ordering visualization tool which uses map like elements to group similar concepts within a region and contrast dissimilar groups as separate elements. The '460 patent does not disclose a geography game show that provides an educational learning experience.
[0045] U.S. Pat. No. 5,743,745 to Reintes discloses a device for playing back short films and/or advertising spots and/or quizzes. The device allows insertion of short films between questions and answers according to regional and supra-regional requirements. Answers provided by the contestant are stored and treated correctly in spite of the insertion of the short advertising film clip and sequences modified at will. A mechanism is thereby provided for inserting advertising clips. The stored responses from the contestants or competitors maintain the continuity of the game show, but do not provide a geography game show that provides educational learning experience
[0046] U.S. Pat. No. 5,916,024 to Von Kohom discloses a system and method of playing games and rewarding successful players. Two signals are broadcast simultaneously from a TV or radio station, the first signal has a first group that broadcasts the program. A second group provides a signal transmission setting forth a task, such as answering one or more questions broadcast in the first group. The second signal is an instructional group identifying the time allocated for responding to the question, proper content and form of answer, as well as the mode for scoring. Remote program recipients use a television set and circuitry to receive the second signal to obtain instruction. The response equipment includes a keyboard and timing circuitry. Each response provided is stored and compared with acceptance criteria and correctness of response, and scored using circuits and print outs or magnetic records containing redeemable prize data. This interactive system requires specialized equipment and does not allow the user to interact with the system over the Internet. It is not a geography game show that affords an educational learning experience.
[0047] U.S. Pat. No. 6,171,188 to Elstner discloses a game device for an entertainment show for providing more dynamic image layout. A monitor wall composed of several monitors, signal sources for graphical and or textual display. A group of monitors comprising a portion of the monitor wall may be assigned to a player and may be activated to provide an optical signal when the player pushes a mechanical switch or a buzzer. The studio camera does not have to swivel back and forth between the monitor wall and the candidates since the monitor wall is right behind the candidates. No disclosure is contained by the '188 patent concerning a geography game show or means for providing an educational learning experience. Rather, the '188 patent discloses a display device within a game show.
[0048] U.S. Pat. No. 6,174,237 to Stephenson discloses a method for a game of skill tournament. This interactive computer-based system evaluates the skill level of a player. In the qualifying round the player competes against the computer. Scoring the highest number of points qualifies the player for the highest performance level, whereupon the player is given a reward. In the play off round, players reaching the same level of performance compete against the host computer. A local area network (LAN) or wide area network (WAN) provides a set time period for the competition. The player with highest score is rewarded. No disclosure is contained by the '237 patent concerning a geography game show or means for providing an educational learning experience. Instead, the '237 patent discloses a computer device that determines a player's skill level.
[0049] U.S. Pat. No. 6,267,379 to Forrest et al. discloses an electronically interactive location-based multimedia game system and a method of interaction. The game is played in rounds with a team of players participating to come up with one or more answers for a given multimedia multiple choice question involving identification, matching, oddball element recognition, linking or poling of factual data within a preset time period. The player teams may be collocated in a location-based facility or may play via the Internet. When the teams select correct answers, an indication is provided and score is maintained to determine the winning team. Such a multimedia interactive game provides no disclosure concerning a geography game show that affords an educational learning experience
[0050] U.S. Pat. No. 6,384,868 to Oguma discloses a multi-screen display apparatus and video switching processing apparatus. The image screen consists of a main image, a sub image A and a sub image B. The main image is combined with sub images A and B by determining if sub images are in even field or odd field to eliminate flicker. The combined image is written into a video-storing device and read to produce a stationary or smoothly moving sub images without flicker. One of the sub images can be turned off or switched on smoothly without flicker. This multi screen display apparatus and video switching processing is not a geographic game show.
[0051] U.S. Pat. No. 6,439,997 to Brasseur et al. discloses a television/Internet game show. Internet users register and answer a questionnaire to create user profiles that are randomly selected and posted on the TV game show web page. Internet users get to vote on these profiles to select a winner. The winner receives a large monetary award during a live TV show provided by the advertisers. The winner must spend the award during a preset time period or forgo unspent portions thereof. No disclosure is provided concerning a geography game show that creates an educational learning experience. Instead, the Brasseur et al. patent discloses a lottery game having a televised award ceremony.
[0052] U.S. patent application Ser. No. 2002/0016196 to Orak discloses an Internet game show in which a visual clue is progressively exposed to contestants or competitors, providing visual clues. The contestants or competitors log onto the game show at the same time and are allowed to see the questions progressively. Questions are viewed as a stream of data from the game show host server computer. The questions may also be loaded into the contestant's computer and revealed progressively using special software. Each of the contestants or competitors fills in a blank area to provide a textual response and returns it to the game show host by activating a send button. The software returns this response with a computer-generated time stamp to account for the Internet transmission time delay. The contestant that provides the earliest correct response is the winner. Each of the contestant's computer clocks must be set to the same time, which is oftentimes not feasible. No disclosure is provided concerning a geography game show that affords an educational learning experience. Instead, the patent discloses an interactive Internet game.
[0053] U.S. patent application Ser. No. 2002/0083436 to Fidler discloses a method for a network-televised commercial-free game show in which revenue generating advertisements and entertainment are integrated. A predetermined number of contestants or competitors is selected and provided with a square game board connected and integrated with an Internet advertising support system link to the show. The square game board comprises many unlighted squares having randomly generated numbers, and a blank center square. A segment of an advertiser's commercial is shown to the contestants or competitors and to the public. Contestants or competitors must provide a response relating to the advertised product. If a correct response is provided, a light is turned on in the square game board; otherwise no light is turned on. The advertiser's commercial is displayed in its entirety. When complete array of lights in the contestant's game board is lit along a horizontal, vertical or a diagonal line, that contestant is a winner. The game show uses advertising commercials as an integral part of the show. No commercial breaks are needed. Revenue is generated from commercials as well as an Internet system link. No disclosure is provided concerning a geographic game show. The Fidler application tests the skills of contestants or competitors regarding the knowledge of advertised products.
[0054] U.S. patent application Ser. No. 2002/0125637 to Leis discloses a word game and methods for conducting the same. This word game is playable by one or more players. It comprises a plurality of syllables in text boxes with value options. When a value option is selected, a clue is provided. The player that made the selection must then come up with a word that comprises the syllables provided in the text box. Correct answers are rewarded while incorrect answers are penalized. This word game can be played as a television game. No disclosure is provided concerning a geography game show that creates an educational learning experience. The Leis application discloses a video game; not a TV game show.
[0055] Foreign Patent No. FR 2689413 to Gaston discloses an educational geographical game. Towns are noted on a map having a rectangular frame. A removable map is held by the rectangular frame. A graduated ruler pivots on the frame to show positions of towns. The removable plastic frame allows placement of maps within the frame, while the pivoted graduated ruler sweeps across the map, allowing players to note the exact positions of towns. The Gaston patent discloses recording the positions of towns within a map. However, it does not disclose a geography game show that provides an educational learning experience.
[0056] The background prior art may be summarized as doubtless creative and useful for educational, entertainment and skill challenge, including especially the games shows and electronic games that are presently on the market, being televised and being played by millions of people.
[0057] However, the present invention seeks to improve perceived weaknesses or deficiencies in a new game that may be called many names, but preferably named “WordSmith Wars™,” over the above discussed games and game patents which often possess small variety of play, slow change of game pace, limited intensity of play, limited direct competition of contestants or competitors one to another (and among audience players, as well), difficulty of adding new elements to make the game fresh, old word games that require a contestant to “keep their head down” as they write, and thus are not easily put into a verbal, rapid fire, exciting format of play—and thus are not easily engaging to the audience, games that are not easily understood or complicated when game requirements and objectives are figured out, limited word and linguistic-related educational value, little or no “bidding processes” to gain skill advantage, limited “surprise” elements throughout play, low or minimal entertainment value. These above games, so many which have excellent elements and “fun” value also have other shortcomings, such as limited breadth of challenge within the “game world” of games, as well as a lack of intrigue and strategy, as well as a low level of intense competition that is missing in most of the game show games, especially, as discussed above.
[0058] Moreover, as will be seen further in the summary, specification and claims, the game diversity that is lacking in some of the present dominant TV games may be improved upon by providing a fresh array of novel game and game show options for players, contestants or competitors and audiences through the novel, unique Mini-game module” “game modules-within-a-game” process and structure. Also, improvements are made by providing educational, exciting, challenging and diverse game play, in addition to and more than other games of the past, whether computer based, board game based, or game shows, all games, both unpatented and patented, that are demonstrated in the games formerly or presently on TV or in any medium, mentioned in the patents referenced and discussed above and below, relevant to the game inventions herein.
SUMMARY OF THE INVENTION
[0059] In the first of three representative, preferred embodiments, novel games, aka, “Wordsmith Wars™” and herein also denoted as: WSW, playable by one or more participants, are disclosed comprising individual game modules that have assigned value accruing to the module-winning player(s). Modules are selected preferably by a chance or random indicator mechanism that comprises indicia upon them relating to a particular game that the contestants or competitors are to play (or any other function of or step(s) to take in the game). The chance mechanism may be a chance wheel, cards, dice, spinning globe with indicia, balls that roll into indented platforms, tubes or boards with indicia, as in Bingo game apparatuses, et al.
[0060] These game modules, which are comprised of novelly content-provided, formatted and constructed, arranged and sequenced-for-play, “mini-game,” short-duration games. These mini-game modules are played successively in preferred “TV Show” or (main game) in groupings or “segments” of a predetermined and general set amount of time within a game episode (typically ½ hour to 1 hour in length). Each module game completion may also be considered as playing “one round.” The modules are collectively arranged or sequenced into these game segments that combine to make up a said single “show episode” before or preferably during the game play. These modules are chosen by the host or contestants or competitors, or even the audience (studio or home) using a chance selector mean, as mentioned above, to select the particular module that the contestants or competitors are to play throughout the game episode. The predetermined game content modules' duration would corresponds with the show segments and show episode duration and the commercials, and station breaks would be accordingly interspersed within the segment and and/or game modules, as convenient. It is typical in today's average TV Game Show that approximately 20 minutes out of a half hour show would be dedicated to commercials and stations breaks, including internal show commercials.
[0061] The WSW game includes points, cash or prizes awarded for a correct answer to a game module word answer. As well, in preferably, most if not all, module game answers, a penalty, such as point or money or prize deduction (or partial deduction) is given for an incorrect answer. A player's score is the accumulated points, cash or prizes won by giving correct answers. WSW is played in rounds or game modules that are of optionally varying duration and in number of game modules actually played. The player with the greatest score (or money or value of game winnings) at the end of the last round played is the winner.
[0062] The modules are typically, preferably most often related to “word games,” as provided in a unique WSW “game platform” invention, and some of the names and games may be non-proprietary games, such as crossword puzzles, “Boggle®-type” word extraction games, etc., or fully originally conceived or modified games created by and designed by the applicant-inventor. Other trademarked and well-known game modules may be potentially licensed from the mini-game modified module owners, such as Scrabble® (Hasbro® Games), Boggle®, Scattergories® (It is to be noted that the licensing opportunities with such “branded” games could provide a huge synergistic and mutually beneficial relationship to “use” the branded game on the WSW TV or internet WSW game platforms—which would provide a huge market audience for the branded game company). Some other non-proprietary games within modified game modules herein may simply be public domain games, like Crossword Puzzles, and a myriad number of internet word and other games that test spelling, vocabulary, jumbled letter word extraction, grammar, picture identification, category listing, anagrams, acrostic puzzles, rhyming, root word games, etc. Some of these non-proprietary game modules may be named the following, not including some others to be discussed and illustrated in the following drawings, as well as further in the summary and detailed description: Grammar Hammer™, Word Wedges™, Smithereens™, Blazing Bellows™, Coal Pile™. Horseshoe Hunch™, Missing Brick™ Anvil-Block™, Joggle Tongs™. Smythical™, Macro Morph™, Blaze-a-Phrase™, Poetic Prowess™, Word Roots™, Pass the Coal™, Word Rage™, Pro-Nounce™, DEFIGNITION™, Fusion Fable™ are some examples of only just a few of many possible in addition to the other the modules in which game play is more fully explained below.
[0063] The format or play stage could easily be cards and a physical Wordsmith Wars™” game board (on a table, for eg.,), as would be similar to a traditional Monopoly™ Game, as well, whereby the said modules above may be played. However, the preferred method and substance of carrying out the invention is in a TV Game Show. Some game shows of which, as Wheel of Fortune™, are mentioned above as exemplary TV game shows of a successful TV game format. WSW would seek it own format that may be adjusted and refined into an equally compelling, successful TV Game format and stage set. As well, the game would be additionally useful and entertaining in the internet realm as mentioned below and above.
[0064] These modules are thusly unified into a unique, composite, single “Wordsmith Wars™,” “Word Wars™” (or other appropriately named “unified/composite” game name) preferred embodiment being a game show, which further may have a common theme(s) associated within the game content modules. For example, a nature or adventure theme, a WWII theme or other historical theme, or a Pacific Ocean aquatic theme, or a sports theme, etc.
[0065] Intrigue and suspense, as well as strategy can be increased as letter(s) that are extracted out of certain “hot words”, explained further herein, are “won” from the inception of play throughout, until needed in final round(s) of game by a contestant. As well, word(s), and/or their correct word-in-phrase and “letters-in-Hot-Word™” positions, in addition to points or money won, may also be won throughout play. These word and/or letter “threads,” are strings or a series of letters (that will be used to create words, later used in a final round, preferably called, “Scramble For Your Life™”. This series of letters is preferably termed Hot Letters™, Hot Words™ and Key Phrase™ Words (which may be symbolized by a “key” within the game graphics. These all may be collected by the contestants or competitors, then strategically used to advantage in a climactic final round or game module, such as in a said “Scramble For Your Life™” or other climactic final round.
[0066] In addition to the excitement generated and intense competition that may be built up during play “winning and collecting” these Hot Letters and Key Phrase Words, there may ALSO be another complimentary, second combined Hot Letters and Key Phrase Words collection/accumulation event, through a strategic letter and/or word bidding process. In other words, in the final “Scramble For Your Life™” module the contestants or competitors may use their Hot Letters they previously won—throughout the earlier game module play—and also “combine them” with later Hot Letters and Key Phrase Words won (preferably just BEFORE that final Scramble round), in this bidding process for more Hot Letters™, as well as Key Phrase™ words to advantage them in being the first to finish the Scramble For Your Life™ round, and thus win the game.
[0067] The WSW™ Game final winner—determined by the final “Scramble For Your Life™” module—may spin a final (optionally included) “Win Spin,” which may additionally entitle them to have a chance at multiplying their winnings, adding prizes, or even losing a portion of their winnings Or, they may even have a rare chance at the million dollar prize (if they have met the criteria—explained further herein) for that opportunity.
[0068] The game may be adapted into a typical physical stage show or any electronic or board (table) game formats that involve players watching or participating in the game through use of any of the broadcast mediums in which persons watch or play games. Television game shows, including interactive TV, and in other communication media, such as over the internet or other interactive communications networks such as desktop and computer pad format, smart phones and many other “connected” devices, all part of what is commonly being called the “Internet of Things” or IoT are potential mediums for formats that may support and distribute the game.
[0069] Moreover, with the WSW™ game's novel characteristics, the following list is provided enumerating just some of the objectives the inventor would like to accomplish with the WSW™ game invention, namely:
[0070] The present invention seeks in its objects to:
a. In a novel game that may be called many names, but could be called “WordSmith Wars™” improve over the above discussed games and game patents, provide a game of wide variety of play options through a unique and exciting unified series of “games-within-a-game” play format, process, method and structure. b. Foster quick change of game pace within such a WSW game. c. Draw players into a high intensity and sustained focus of play that EDUCATES while having “fun” and increases the literacy rate and level of future generations of USA (and wherever syndicated worldwide, in other languages) people. This would involve even school or classroom “credit” or educational credit for watching and/or participating in the game show or playing online and/or interactively. d. Encourage more direct “face-to-face” competition of contestants or competitors one to another, similar to the “Family Feud®” game environment (and among audience players, as well). e. Making the structure and process of such a game more felicitous and simple as to adding new game elements to make the game challenge and content fresh. f. Provide a game play format whereby “fun-to-play” old, non-proprietary as well as proprietary, tried and tested word games that would normally require a contestant to “keep their head down” as they write (for eg., in a crossword puzzle), would be modified and easily put into a verbally expressed, rapid fire, exciting “vocal-format” method of play—and thus be highly engaging to the audience and exciting to the contestants or competitors. g. Provide game modules that are quickly and easily explained in rules or on a game show, by the host—in other words, game modules that comprise recognizable formats like a partially finished Scrabble Game or Crossword Puzzle, in which the space of letters and definition or arrangement of letter is intuitive to the contestants or competitors and audience and wherein the newer novel game modules' game content is quickly understood and intuitive in game play. This would not only also engage all people involved in the game, including viewers, but minimize wasted time by the show host's “reading of rules” or the same as in a board game or internet format. Thus, meeting another objective to keep the game easily understood and uncomplicated and rapidly figured out with ready familiarization by all. h. Having modules that are of word and linguistic-related wide depth of diversity in their educational value because they cover a broad spectrum of word related skill sets required to play those game modules. i. Provide a continuous time of play, yet exciting “break-up” of the game's intense word-competition—ie., some game intensity relief—by having “bidding processes” to bid on Hot Letters for Hot Words as part of the game strategy to both demonstrate contestants or competitors' (or audiences′) additional “non-verbal, non-word related skills” gain skill advantage (see #14 and #17). j. Supplying at least a second “intensity relief” game component whereby unique, humorous, and diverse game modules may be intervening the “normal” more serious game modules—the unique “humor-inducing” modules being preferably consistent “mainstays” in the WSW™ game so that the audience and even contestants or competitors “look forward” to them at predicted intervals of the game. k. Including frequent “surprise” elements throughout play that add intrigue and suspense. l. Setting forth a format that has continuous and increasingly intensifying entertainment value so as to secure good commercial break “comeback” for the audience, thus adding “business proposition value” to justify air time of the game. m. Providing a game content and process of play with the widest scope of challenge within the “game world” of games, focused not on “trivia” answers, as Jeopardy™ and other popular trivia TV Games, but on “cognitive” and thinking process strategy and answers, primarily, though not necessarily exclusively associated with “word-related games.”. n. Embedding within the game a significant path of intrigue and strategy that players must use through normal “module game” play that will significantly advantage them in the games climactic round (see object #17). o. Providing game modules that tests and challenges a variety, rather than a specificity, of word or other thinking prowess and contestant skill, thus providing a game of broader more intense competition, which arguably, is missing in most of the game show games, especially, as discussed above. p. Make it straightforward and reasonable for the game modules and WSW game and game show “content compilers” to craft various game content into episodes and easily form the game segments with the show episodes allotted time, typically ½ hour TV spots. q. Provide a final WSW game round that truly crescendos in its climax of excitement and suspense, called: Scramble For Your Life™” whereby a “thread of letters” (Hot Letters™ and Hot Words™, as well as Key Phrase™) that is built (won) during successful previous earlier game play (from the beginning of the game) is used in combination with the said bidding process of #9 in conjunction with the actual word scramble module, that in combination, tests—under a high, but fun, maximum skill level of the contestants or competitors in several combined categories in one said “module game.” r. Giving the winning contestant a final bonus round based on pure chance that includes a large possibility of doubling or tripling their money, but conversely, also losing some of their winnings to chance, as well.
[0089] 19. Drawing on all the important “successful game philosophy” that make currently popular game shows big winners, Wordsmith Wars™ desires as a further objective to draw huge audiences from all walks of life. By attempting to capture some of the “philosophical” enjoyable chance components and puzzle-solving of Wheel of Fortune, the brainy knowledge aspect of Jeopardy, the suspense and pressure of Who Wants to be a Millionaire, and the “fun-fight” One-on-One confrontation of Family Feud, Wordsmith Wars™ desires to provide a fresh and exciting “different” approach to the games and game show world.
[0090] 20. It is another object whenever, and with whomever possible, to additionally provide game content for WSW with tried and tested games under famous game brands, such as Scrabble® (Hasbro® Games), Boggle®, Scattergories® under licensing opportunities to secure a huge synergistic and mutually beneficial relationship to “use” the branded game on the WSW TV or internet WSW game platforms—which would provide a huge market audience for the branded games in their modules, as well provide original or other “public domain” games to fill content of WSW game modules.
[0091] 21. It is another object to engage with high focus and attention audience participation, for example, as a viewer “at home” can also shout out answers from his or her living room and try to “compete with” or beat the contestant on TV because the “modified-to-verbal-response” the formerly “usually written or typed out answers” to the enjoyable word module games, now keeps contestants or competitors' faces upward as they speak, rather than write their answer, preferably with added competition and participation with the audience at home.
[0092] It is to be noted, though other games shows have claimed the same, WSW can become a powerful educational tool for children and immigrating adults, helping them gain command and use of the English language and may be distributed widely though various optical or magnetic or computer downloadable means through many and varied WSW software versions. Of course, class credit may be given to student, both young ad adult, who watch—or even more particularly “play” the game show interactively through internet means. Students would have a private “key access” code assigned to them or number proving they finished the game, their scores, etc even being. recorded. This could be relayed to the teacher in a classroom setting the next day they attend class, or by email to the teacher.
[0093] As its name implies, Wordsmith Wars™ is a show about solving word puzzles, with a varied assortment of diversionary or “drama relief” additional mini-games or “modules” among the puzzles and word game modules. What makes WSW unique is the fact that an array of exciting individual or “mini” game modules are used—with preferably six (or nine, or more) distinctly different games (as said game modules) played per episode, in preferably two to five or more “show segments” per episode, in addition to or including the mind-crushingly intense, final showdown—said Scramble For Your Life™. The six plus or minus different games played per entire show episode are selected at random using chance selector means by the contestants or competitors from a pool of twelve (or up to 24 or more) possible game modules. This diversity of randomly selectable game play options makes each show episode unique and new—and yet the audience and the skilled contestants or competitors who are invited on to the show will quickly grow familiar with the various game modules and quickly settle on favorites.
[0094] Unlike some former games and presently active “in market” game shows, Wordsmith Wars focuses on intense verbal interaction and direct contestant competition, as well as high diversity and flexibility of game subject matter, all in a high pace rapid fire environment with periodic pressure (from the drama caused by the game modules) by including at least one or two “relief” segment(s) that are fun, as well. Not only do the contestants or competitors answer questions, they also end up voting, constructing, bidding, and problem-solving. Since the unique word game “verbal-based” format (in contrast to what would be typically a “heads down” contestant on similar words games) for speaking out answers is predominant in how the modules are played, the contestants or competitors maintain engagement with the audience and vice-versa. As well, audience participation is heightened, for example, as a viewer “at home” can also shout out answers from his or her living room and try to “compete with” or beat the contestant on TV, thus emboldening them to try out for the show as a contestant, themselves.
[0095] The novelty of course, for shouting out letters say, for example, in a Wheel of Fortune® game is not new to game shows—however, shouting them out in a Crossword puzzle or Scrabble® or Pictionary® type game can be so.
[0096] As a preferred embodiment for one of the chance mechanisms used to choose what game modules to play (as well as other game function) is a chance wheel for WSW, called potentially “The New Wheel™, and is one of many possible chance selecting elements of the game. The applicant has invented a major upgrade to the centuries-old chance wheel, used in such shows as Wheel of Fortune. The applicant/inventor's U.S. Pat. No. 8,596,638 for “Rotatable Hand Grip System” and a second U.S. Pat. No. 8,690,154 entitled: “Safe and Novel, Lightweight Hand Grip Systems for Manually Spinning Gaming Wheels,” aka., “The New Wheel™ is a conceivable chance mechanism and only one of many preferred embodiments of the chance mechanisms mentioned that may be used for WSW, to, among several functions, “select by random means” the particular game modules which to play in WSW.
[0097] As well, other potentially useful chance: mechanisms may also be used instead of “The New Wheel™, namely: cards, dice, spinning globe with indicia, balls with indicia that roll into indented platforms, tubes or boards with indicia, as in Bingo game apparatuses, simple cards in a deck, et al, all which may be modified into the game board, TV or internet formats into which the WSW Game can be formatted.
[0098] However, the applicants other patented and new IP's New Wheel™ introduces and provides a new chance device emphasizing safety and ease of use—unlike its predecessors. As well, The New Wheel™ is elegantly designed, large, yet light weight, and preferably operated with stunning computerized lighting effects, having all the benefits and advantages both, the stage show, the contestants or competitors and the home audiences, as fully detailed in the above said applicants IP.
[0099] The New Wheel™ may spun by the contestants or competitors or the show host to determine which game modules they will play. The wheel can also be used to distribute bonus prizes, and to instigate alternative scenarios for the contestants or competitors—such as losing a turn or losing part or all of their winnings, or being able to choose what game to play, or having to vote between two options. At the end of the show, in a preferred embodiment, the winning contestant spins The New Wheel™ one more time to determine whether he or she will be able to multiply their total winnings by a factor of 1×, up to 3× (or more) and/or possibly receive additional non-monetary prizes, lose a portion, possibly up to half, or more, of their winnings, or possibly win the rare prize of one million dollars.
[0100] All of the show's early game play leads up to the climactic showdown segment, entitled “Scramble For Your Life™” In this mind-roastingly intense finale, the two, three or more contestants or competitors each use their cumulative winnings to bid at auction for the placement of key words in a Key Phrase™, as well as Hot Letters for said Hot Words (words that are contained in a final position within the said Key Phrase, but with only certain letters filled in that were won by the contestant and others added to those that were successfully won in the final bid process), in a scrambled word puzzle. (The puzzle, named Key Phrase™, is likely to be a famous poem, quotation, or excerpt from a classic work). The host, a highly capable auctioneer, sells off each word or Hot Letter™ to the highest bidder. When all available or predetermined word related items have been sold (it is preferred, though not definite that these items' “positions” in the Hot Words or Key Phrase are what is being sold/bid for and not the letters themselves), the contestants or competitors have from 30 seconds to one minute to solve the puzzle—each with the individual “Hot Word letter positions” they have purchased (won) in the auction and Hot Letters they won during earlier game play. It is possible to have an option to buy the letters themselves and positions, but this may give too much of an advantage and lessen competition if other contestants or competitors could not have even an access to some actual letters, though not their position.
[0101] But WSW isn't all high-pressure intensity. Two special daily show segments are designed to break up the drama. Early in the episode, the Pic-in-a-Poke™ game brings intrigue and human interest to the show. Preferably, a new guest artist is brought in each week, either remotely, in real time in presence at the studio, or prerecorded drawings may be used to sketch rapid-fire drawings for the contestants or competitors to guess. Each correct guess scores money toward the contestant's winnings Right before the final said Scramble For Your Life round, a bit of comic relief is introduced through the Funny Forge™ Game. Here, an unusual word from the English language is presented, and each contestant must concoct the most humorous “purposefully silly” (but clever) meaning for it. Additionally, the contestants or competitors may “sue the word in a “funny sentence” that illustrates their humor prowess and linguistic and creative ability to engage an audience.
[0102] Then, the three humorous answers are read off either by the host or, preferably, the contestants or competitors (to test their persuasive power of humor and oratorical and linguistic creative ability, along with a fourth answer—the correct one. This fourth answer is an actual genuine attempt—for extra points or money—at guessing the correct definition of the word (given along with their Funny Forge™ answer). The studio audience (and/or the television audience) then votes. A total of $5,000 worth of prize money (or a different amount) is assigned to the game. The studio audience's votes are recorded electronically and tallied for each answer. The prize money is proportionately split up for the three contestants or competitors according to how many votes their individual forged words received. One option is for the contestants or competitors to simply give the definition of the word—like Balderdash® and attempt to convince the audience they know the definition with their guess. Another optional game play is for the audience members who actually guess the correct definition of the word get to split the proportionate prize money (or have their own separate reward for doing so) for the correct answer. *1 *2
[0103] Note: The above *1 *2 (other numeric asterisks): These are sub note references explained in text below within the Summary and following Description that help further explain the working of the additional aspects of the WSW Game.
[0104] A vital component of any game show is the host. WSW desires to find a famous show biz veteran, or a younger upstart, with an affinity to the WSW game and the type of contestants or competitors and audiences who are to watch/participate. The host must ender himself or herself to the entire philosophy and exciting entertainment and challenge of WSW.
[0105] The 21 objectives above, as well as other purposes and function of WSW may be more clearly understood in the three preferred game show embodiments, some ancillary explanation of modifications of these embodiments, as they would be practically applied to real game show play.
[0106] Also, it should obvious, once the game strategy, content and philosophy has been revealed herein this application, that “morphing” or modifying the WSW game contents, functions and components and the game's philosophy from the Game Show formatted main embodiments preferred market introduction into the game show world, that a game board version, as well as various online, interactive internet versions are all desired valid “WSW “vehicles” that could easily adapt this proprietary IP into various other non-TV game show formats, methods, processes and components through various WSW software versions. Yet, attention is and will be given to these secondary “vehicles” in this application with which to format the game herein following in this application and above.
[0107] Consideration, next, is directed to the said first preferred Game Show “WSW vehicle,” that is, game function and formatting of the scoring and game module content and player rules and function, emphasizing the content that will be integrated into the illustrated game show embodiments #1, #2 and #3, respectively, described thereafter primarily comprising the sequence of game actions, their duration and grouping into segments within a full game show episode. Detailed content, function and process and names of exemplary WSW game modules and following explanation of the actual game show formats' three embodiments will be discussed in this Summary, as well, particularly through asterisked, numeric notation, as the other WSW game vehicles of a board game and digital and internet or “cloud based playing” of the game.
Standard Game Scoring
[0108] Each correct response nets the contestant preferably a typical either, $125 up to $250 in a “bronze round” (a lesser preferred round designation is ‘bronze’, as silver and gold are preferred nomenclature and game levels), or $250 up to $500 in the silver round, and $500 up to $1000 in the gold round. (This amount can be adjusted as necessary to fit research results, based upon what the maximum average amount the WSW Show can afford to disburse). If a contestant gives an incorrect response, an amount up to the score value is deducted from their total winnings at that moment. This is the normal, standard scoring system used with most game modules in WSW. A few modules may have different scoring structures, which will be explained further in the description of these specific game modules in the asterisked sub notes and elsewhere.
[0109] Various “game cue sounds” could be used for actions of the game and contestants or competitors' responses, of which several can be in the form of “old school” typewriter noises, as for example from an old manual typewriter, as in the clicking of the carriage return lever and the “ding” when the typewriter carriage slides across into return position. The sound of the platen knob being turned to adjust paper upward and downward, and other function noises are other examples of sounds that can signal a module win or end of a round, or various other game stage events. As well, the concept of a WordSmith as a subset of person related to a and old world “typesetter” or MetalSmith could be intermingled with the sounds and “clinks” of a metal forging press or hammer and anvil strike, as well as blow furnace, all sounds to enliven and intensify the already exciting game experience.
Standard Game Modules—
[0110] These following game modules are elected by chance mechanism, e.g., chance wheel either by the show host, a host assistant or the contestants or competitors themselves, as for example “spinning a special wheel” or, as well, using cards, dice, spinning globe with indicia, balls with indicia that roll into indented platforms, tubes or boards with indicia, as in Bingo game apparatuses, et al, during or before the game or any of the said “chance selection mechanisms” spoken above and throughout herein.
[0111] Note: The method of answering is always primarily verbal, however some stand module games may allow for the contestant to look down and write or manipulate upon their personal computer screen (such as they would in the final Scramble For Your Life round. Otherwise all the standard modules will have a general procedure (though anything may be adjusted or modified) as follows: The show host announces the game that the chance selector lands on and then the module game is also immediately flashed upon and revealed on the big screen in front of them and in view of the TV and studio audience, as preferably the host gives a very rapid and succinct clear explanation of the object of that module game and scoring. Though the standard module, in addition, may be also included on the contestants or competitors' personal computer pad screens in front of them, this is not preferred, as it allow the contestant a chance to “look downward” and thus “disengage” with the audience. If they have a personal computer pad or screen it would be within or upon preferably their individual personal podium, behind which each of them stand). The said New Wheel™ is the preferred chance selector means, which would be horizontal to the floor in front of them, similarly to how Wheel of Fortune arranges their game wheel.
[0112] It is to be noted that these standard game modules may have a theme associated with them.
[0113] The preferable New Wheel with from 24 to 32 or more wedges would have upon the wedges with indicia of the names of these “standard” game modules. If there were 10 games to choose from there could be double for each game leaving say 30−20 wedges=10 other wedges with which to add prizes and other gifts such as loose turn or lose money or award, as in a “Kaboom” type graphic with a 25% or 50%, etc. loss amount depicted thereon.
[0114] Just a small selection of game modules possible are provided under the following game names. These are not at all exhaustive of the hundreds of game modules that may be designed or modified from presently similar word games being played extensively by those enjoying game of all ages and preferences.
Grammar Hammer™
[0115] A click-in game module
Standard scoring structure
[0116] Each puzzle is a grammatically incorrect sentence. The contestants or competitors use their clicker buttons for the right to answer. The host acknowledges the contestant who clicks first, who may then verbally answer the puzzle. For example “The word ‘lay’ should be “lie” in the sentence.” The contestant must say the correction to the sentence in a way that is clear. He need not repeat the entire sentence, but must clearly correct the error and include enough of the surrounding sentence structure to clearly indicate what must include the corrected grammar wording. Note: This will require fast and alert “judges” since there may be more than one correct way to correct the sentence.
[0117] Additional puzzles (incorrect sentences) are introduced for the contestants or competitors to guess until the game module segment runs out of time.
[0000] MY Times™ Crossword (this Module May Also be Called: “WW Times™ Crossword”
A click-in game module
Standard scoring structure
[0118] The host introduces a sizable “partially completed” crossword puzzle. The puzzle is partially completed, with several words already in place. The clues to the remaining words are listed along the side or bottom of the screen, like any ordinary crossword puzzle. The host then calls out a number and letter combination “cross point” such as “F14” representing a blank or partially blank word that may or may or may not have letters within any of its blank boxes, and the contestants or competitors use their clicker buttons to be able to answer. They continue until either one or some, possibly all the words are solved in the puzzle, or the game module segment runs out of time. If necessary, a second crossword puzzle could be introduced if there is enough time, whether or not the earlier puzzle(s) are fully solved.
Smitherines™
[0119] A click-in game module
Standard scoring structure
[0120] A large word in the 10-14 letter range is presented on the big screen. The host shouts out the number of letters required to be extracted and verbally stated in the derived words. For instance, “Five letters words!” The number of letters required in the derived words successively increase throughout the game. To give a solution, a contestant must click their button and shout out a derived word of the proper or exact length, made from the letters in the large word. If at any time, a contestant can derive a seven letter word instead of the shorter derived word, he will receive an extra prize, such as $1,000. Additional new words can be given if the module segment time allotted permits.
Quotable Quotes™
[0121] A click-in game module
Standard scoring structure
[0122] A quotation is displayed on the big screen with a blanked out word. (with a small blank for each letter representing the letters in that word). Contestants or competitors click in to reply, and must supply the correct word to fill the blank. If no one replies at first, letters begin to appear in the key word's blanks, slowly revealing the word until a contestant is able to guess it. As many different quotations are given as there is time for in the game module time allotment, or until a set number of puzzles are solved.
[0123] There are several options for enhancing this game module. These options could be installed separately or in combination.
1. All the quotations would be from a single person or source, and the contestants or competitors would guess this author or source for an extra bonus prize or dollar amount. 2. All the quotations could pertain to a specific theme, which the contestants or competitors could guess for an extra bonus prize or dollar amount. 3. Possibly other options.
Smythesaurus™
[0127] A click-in game module
Standard scoring structure
[0128] Potentially based on the most recent Roget's International Thesaurus 7th edition, for example, contestants or competitors are given either a word for which they must provide either a synonym or antonym. Words in the thesaurus are listed in sequential order. The contestant must identify either the first, second, or third word in the definition list for that particular word. As many different words are given as there is time for in the game module time allotment, or until a set number of puzzles are solved.
[0129] Option: Allow a second contestant to guess on any given word, extending the sequence to the top five words (or more) for a score.
SmytheSpell™
A Respond In Turn Play Module
[0130] Standard scoring structure
[0131] The host verbally presents the spelling words (along with the Big Board preferably including them), one by one, and lets the contestants or competitors spell them, like a spelling bee. Contestants or competitors will Respond In Turn, each to their own spelling word. That is, unless a contestant misspells a word, then the next contestant must spell the word that was missed. Unlike an old-fashioned spelling bee, however, contestants or competitors are not eliminated for missing a word, they simply don't score or they lose the points they would have gained for that word. It is preferable that the words to spell become more and more difficult as the bee climaxes. The letters would pop up in place consecutively on the big screen as the contestants or competitors said them, enabling the audience(s) a more engaged play along. Optional bonus prize (money or other) may be given to a contestant who makes it through the entire spelling bee without missing a single word. There may be an option to pick out the misspelled word in a sentence or list and correct it—this option may break up monotony, if needed.
PIGEONHOLES™
A Respond In Turn Play Module
[0132] Or “Write List” or verbal call out, word answer method
Standard scoring structure
[0133] Players preferably, verbally state out loud (or ‘pigeonhole’) as many words as they can that belong to a category, starting with a given letter. One derived meaning that Merriam-Webster assigns to the meaning of the word “pigeonhole” that has bearing on how this game is played is: “pigeonhole” is used to say that someone or something is being unfairly thought of or as described as belonging to a particular group, having only a particular skill, etc., or as would apply to a limiting quality defining a category.” This game has some content similarity to Scattergories®
[0134] The host may give the letter to start with, or either host or contestant may just spin the wheel (decked with letters upon the wedges), and whatever letter it lands on is the letter the contestants or competitors will use that turn. Then the host gives them a category. A simple way to execute this game verbally and the preferred method is to have the contestants or competitors take turns in sequence to give their word answer out loud until all players cannot give any more words. Wrong answers require score value deducted. (Note: Judges would have to be very astute and issue a clear set criteria of word parameters allowed must be made clear to the contestants or competitors, as there are subjective elements to what words are outside bounds of a “normal” answer).
[0135] Another option is that as soon as the category is given, the contestants or competitors have twenty or thirty seconds range of time to write down as many things as possible in that category. They write on their electronic screen or pad on their preferable podium tops in front of them. The audience can see their entries on what may be included in the show set BIG SCREEN behind them. When the buzzer goes off, the host allows the contestants or competitors to list their entries one at a time, turn by turn. Any entries that are UNIQUE to that contestant are allowed to stand. If two or more contestants or competitors list the same entry, it cancels out and no one receives the money for that word. If any contestant lists a word that does not qualify for the category, they receive no money for that entry.
An Example:
[0136] The letter spun is “S”. The category revealed is “Animals.”
[0000]
CONTESTANT 1
CONTESTANT 2
CONTESTANT 3
Seal
Squirrel
Sable
Squirrel
Swan
Shark
Swan
Sheep
Squirrel
Snake
Skunk
Sheep
Stegosaurus
Skink
Springbok
Snake
Sphinx
[0137] In this case, the host allows C-1 to list his first animal. “Seal.” Nobody else has Seal, so it stands. C-2 lists “Squirrel.” But the other two contestants or competitors also have Squirrel, so it is eliminated from all three. C-3 lists “Sable.” The judges check to confirm whether it is an animal—let's assume they believe it is. C-3 gets to keep Sable. C-1 shares his next animal, “Swan.” C-2 has Swan, so it cancels out for both of them. C-2 then gets to share his next animal—“Sheep.” C-3 also has Sheep, so neither of them get to keep it. Now C-3 gives his next animal—“Shark.” Nobody else has shark, so it stands. C-1 shares his next entry—“Snake.” C-3 has a snake, so it is cancelled. C-2 now shares what happens to be his last entry—“Skunk.” Nobody else has skunk, so it stands. C-3 now shares “Skink,” which nobody else has. It stands. C-1 now shares “Stegosaurus.” The judges allow it, so it stands. C-2 has no more entries, and neither does C-3. C-1 may now share “Springbok,” which is allowed, and “Sphinx.” Since Sphinx is a mythical creature, it is not allowed.
[0138] The scores now look like this:
[0000]
C-1
C-2
C-3
Seal
Skunk
Sable
Stegosaurus
Shark
Springbok
Skink
[0139] The contestants or competitors receive standard scoring money for their eligible entries. The wheel is spun again, selecting a new letter. The host introduces a new category. Rinse and repeat as often as the time allotment allows.
ZigZap™
A Respond In Turn Verbal Play Module
[0140] Or “Write List” word method
Standard scoring structure
[0141] The host presents the 5×5 or 6×6, up to 10×10 or more, etc. “grid” of letters—In this game module the contestants or competitors must, one by one, verbally extract words, in turn. Various highlighting, for example, based upon the contestant's color assigned in the beginning of the game, as in a red, green or blue, may indicate a word on the grid that belongs to that particular contestant when they verbally (or, if using the option, write or type the correct word down) answer correctly. Contestants or competitors will Respond In Turn, each to their own next or sequenced turn. That is, unless a contestant misstates or says an incorrect word. Contestants or competitors are not eliminated for missing a word, they simply don't score or they lose the points they would have gained for that word. It is preferable that the word grids throughout the round become progressively more and more difficult. The words won also may alternatively or additionally be listed on the big screen and pop up as the contestants or competitors said them, enabling the audience(s) a more engaged play along. Optional bonus prize (money or other) may be given to a contestant who makes it through the entire module round without missing a single word during their turns.
[0142] Similarly to the game module of “PIDGEONHOLE™ above, is that as soon as the category is given, the contestants or competitors optionally have twenty or thirty seconds range of time to write or type down as many “grid words” they can find as possible in that category. It is to be noted that in any of the games the show host may limit downward or increase the required NUMBER or amount of letters in a given word answer request of a given module. They write on their PERSONAL electronic screen. The audience can see their entries on what may be included in the show set's BIG SCREEN behind them. As an optional method of play, when the buzzer goes off, the host allows the contestants or competitors to list their entries one at a time, turn by turn. Any entries that are UNIQUE to that contestant are allowed to stand. If two or more contestants or competitors list the same entry, it cancels out and no one receives the money for that word. If any contestant lists a word that does not qualify for the category, they receive no money for that entry.
Blazing Bellows™
[0143] A click-in game module
Standard scoring structure
[0144] Players must get through a rapid-fire series of word definition matches by calling out matching definitions to word and definition lists designated by number and letter.
[0145] After explaining the game briefly, the host introduces all the words and definitions at once on the screen. Basically, it's set up like matching—the words are on the left, and the definitions on the right (scrambled up, of course). As soon as the words are seen, the host allows the contestants or competitors to Respond In Turn, shouting out a matching word/definition pair. They have a very brief time to do so—maybe five seconds once the host says their name. If the contestant guesses correctly, they receive the standard amount of money and the matching pair is eliminated from the board. If they do not answer correctly, the next contestant takes his/her turn. This is repeated until all the pairs are matched, or the time limit for the segment expires. Ten matching pairs may be ideal for this game. Twelve might be all right. Fewer than ten would probably not be enough. There may be EXTRA definitions included to make it harder to match the words, especially as the process of elimination takes over when they are nearing totally matching the list of ten or twelve words and definitions. For example, ten words may have fourteen definitions, etc.
[0146] There are several ways an animated “obstacle path” could be incorporated into this and nearly all the other module games. Tech support personnel could provide a cartoon-like visual aid for the audience while the contestants or competitors play the game. There could be a huge graphic cartoon representation of the contestants or competitors going through the WordSmith Wars™ shop, for example.
KEY STOKES™
[0147] A click-in game module
Standard scoring structure
[0148] Contestants or competitors say the letters, or the studio/stage computer pops up letters until one contestant guesses the word. This is similar to Hangman.
[0000] Chime th' Rhyme™
A click-in game module
Standard scoring structure
[0149] Fill in the blank, verbally, with the correct rhyming word.
Word Wedges™
[0150] Standard scoring structure
Respond in turn A block with letters having spaces between them on one or more lines has another group of letters underneath the block which are used to make words of various length, as required by the host.
Coal Pile™
[0151] A click-in game module
Standard scoring structure
[0152] A “graphic of a shovel tip has letters (hot coals—typically vowels) falling out into a pile of mostly or exclusively, consonants. Contestants or competitors verbalize answers as the host shouts out the required number of letters required for scoring.
Special (Non-Standard) Game Modules
[0153] These following modules are preferably always included in each episode
Pic-in-a-Poke™
[0154] A click-in game module
Standard scoring structure
[0155] An artist (guest, or host) would draw or paint (with any conceivable medium) a series of images for the contestants or competitors to guess the word depicted by the picture. Contestants or competitors use their clicker buttons to answer, and shout out the exact word for that which is being drawn. This may continue as long as the time limit allows or until all preplanned picture puzzles are exhausted. The drawing can be either in real-time or pre-recorded for the show. NOTE: a great additional show revenue producer is: The artist's drawings can be auctioned on the internet or in person, after the show for additional income, as on EBay® or other bid sites, even write in private bids taken by the studio or game show syndicate.
Funny Forge™
[0156] Special rules and scoring
[0157] Here, an unusual word from the English language is presented, and each contestant must concoct a fictitious, hilarious meaning for it. The contestants or competitors record their fictitious definitions, which are electronically sent to the host's private screen and hidden but locked in also privately on the contestants or competitors' screens. Then, the three fabricated answers are read off by the host—or the contestants or competitors, in turn—along with a fourth answer—the correct one. *Note: to engage audience and contestants or competitors even more, it may be even more hilarious for contestants or competitors to “USE” their word in a fabricated and funny sentence illustrating their ridiculous meaning! A “Funny Forge™ Sentence” allows them to express their humorous and skillful usage and power with inducing laughter in the audience in a real illustrative and riveting communication.
[0158] The studio audience (and/or the television audience) then votes. A total of, for example, $5,000 worth of prize money or points (or a different amount) is assigned to the game. The studio audience's votes are recorded electronically and tallied for each answer. The prize money is proportionately split up for the three contestants or competitors according to how many votes their individual forged words received. The audience members who actually guess the correct definition of the word get to split the proportionate prize money for the correct answer.
Optional Format:
[0159] Similarly, an unusual or obscure word from the English language is introduced by the host. Each contestant gives a purely fictitious, most humorous definition of the word they can think of, that is written down and later verbalized. * The three funny answers are shown anonymously up on the big screen. The host asks each contestant in sequence to read their response, and then use the word in the most humorous illustrative sentence possible. Note: The method may be modified to keep all the answers private until each one is revealed at the time the contestants or competitors reveal their verbalizing of their answer.
[0160] *As an option, each contestant can also guess the correct definition for a bonus standard score value. This is done during the time of recording their humorous definition for the word and the audience is not involved in this vote, but the host simply reveals the contestants or competitors who have the right answer also, and thus have that added to their score value.
Scramble For Your Life™
[0161] Special rules and scoring
[0162] The host, preferably an accomplished auctioneer, introduces a category (i.e., Victorian Novel, or Presidential Quotes, for example). Then the host reveals the scrambled puzzle on the Big Board SCREEN so the contestants or competitors see how many word blanks it has. All the words (individual word spaces or lines) of the puzzle will be scrambled, except for two words (the Hot Words). These Hot Words will be blanked out letter by letter (possibly, additionally, these words will be also fixed in their proper sequenced space within the phrase's blank word spaces) for the Hot Letters.
[0163] The contestants or competitors use their accumulated winnings to bid on two categories of information regarding placement of key letters (called Hot Letters) and the key words' (Key Phrase Words) exact placement within the scrambled phrase. First, the host auctions off the *Hot Letters (The actual letters' position is what the contestants or competitors bid for, since all the said Hot Letters—the actual letters themselves—will be available incrementally, as they are won in the earlier segments of the main game (ie., posted on the “Big Board”), and as well, ALL the “remaining” Hot Letters will be “Upon the Board” for the Auction. So, it is the positions of these first set of letters and then the Auctioned letters that all will see. The auctioned letters are simply those not previously won and assigned to contestants or competitors during the earlier game modules. Then, the host auctions off certain Key Phrase Words of the puzzle based on their position. * These positions are preferably, but not limited to the first, last, second, next-to-last, and dead-middle words in the scrambled phrase.
[0164] The color of the correctly positioned Hot letters and words would be, for instance, a “blue” color—all words or letters in blue are final positions and locked in—they cannot be moved by a contestant in the Scramble For Your Life round. All other non-final positioned words and letters would be in red, for example, and subject to moving by the contestant
[0165] When the auction is finished, the host announces that the contestants or competitors have one minute to solve the puzzle. The contestants or competitors use individual interactive electronic devices located at or on their podiums, to solve the puzzle. Note: It may be preferable to have contestants or competitors use only one hand, thus allowing equal advantage to “physically challenged” contestants or competitors who are missing use of or missing a hand or fingers, as perhaps an injured military person. On their individual screens, the *Hot Letters that they have won during previous play, for the two Hot Words described above, are locked in position, and privately revealed to each respective contestant. These Hot Letters, as mentioned, are locked into position in preferably a blue color (privately on their individual screens) indicating that their position in the word is properly placed.
[0166] Note: The home or show stage audience may have access to any one or all of the contestants or competitors' Hot Letters and positions or Key Phrase Words won, in for example a “Triple Screen” on the Big Screen behind the contestants or competitors, but, of course, the contestants or competitors do not know each others hot letter positions—but ONLY the actual Hot Letters (listed up on the Big Screen and possibly on the contestants or competitors' individual screens) won. Then, the remaining unassigned *(UN-WON) Hot Letters are placed above the Hot Words area (in the scrambled phrase blocked out area) for the contestants or competitors to maneuver into place to obtain the correctly identified Hot Words with those remaining Hot Letters.
[0167] Simultaneously, the contestants or competitors work on either the Key Phrase Words or Hot Letters and Hot Words, based on what they have won previously. (From Game Modules and the auction). This creates a true atmosphere of strategy and intrigue as to how the contestants or competitors use the limited seconds allotted to finish the Scramble final puzzle.
[0168] The words and letters they have won in the auction that have been properly placed in sequence on their own individual devices in the said blue “lock-down” lettering, inevitably gives any particular contestant an advantage over the others for those “final position” letters, depending upon how many and what positions letters/words they have gained. After fifteen seconds (or alternate timing), the computer begins to reveal additional Hot Letters and Key Phrase Words in their proper positions, with increasing frequency. As this letter revealing process accelerates, the intensity and urgency for the contestants or competitors to finish first increases. The first contestant to correctly solve the puzzle is the winner. The winner preferably receives $25,000 plus his/her remaining accumulated winnings. It may be effective that a feature provides that two losing contestants or competitors in that final scramble round lose half their winnings (perhaps down to a predetermined level, such as $1,000, so no one leaves empty-handed). The results are tallied, the winner is announced.
The Win Spin™ (Final Bonus Round for the Winner)
[0169] The host then shows the winner to the wheel, which has been prepared specially for the Win Spin. (Or, as in current Wheel of Fortune®, use a smaller separate wheel, a scale model, of the large one. Or use a rapidly-deployable insert system to instantly transform the wheel by providing an “Overlay Disc” over the Main Game Wheel Surface/Wheel Game board. Note: The main wheel game surface would have the Win Spin NEW surface OVERLAYED—and—the Win Spin would have a “second” Surprise Win Spin Overlay covering or “overlay” that is REMOVED after the contestant spins the Wheel for the final time. The winner spins the wheel one more time to determine whether he or she will multiply their total winnings by a factor of 1, 2, or 3, possibly receive additional non-monetary prizes, lose up to half their winnings, or possibly win the rare prize of one million dollars.* The Surprise Win Spin Overlay is then removed to reveal on which wedge the flipper stopped. The host then closes out the show.
Very Important: *Explanation of Hot Letters, Hot Thread, and Hot Words, Including Million Dollar Win:
[0170] How Letters are periodically won and assigned to the contestant throughout the game:
[0171] “Hot Letters” are simply “hidden” individual letters contained in “some” individual “module games words”—words that the contestant answers correctly during play, whether they are written out or called out in various correct answers. Not all but just some of those winning answers may have a Hot Letter included therein. Optionally, prior to or even included “dynamically” during play Hot Letter may be assigned to certain correct answers in real time play, by random.
[0172] When a contestant wins the Scramble For Your Life™ module round, he or she may be eligible to get a chance in the final Win Spin™ to win a Million Dollar Prize if these qualifications are met:
[0000] 1. Contestant must win enough Hot Letters™—letter POSITIONS—to fill completely at least ONE of the two or more Hot Words inside/within the final phrase of the Scramble For Your Life Round™. Note: Depending on whether the Hot Letters may be DUPLICATED (when several won module words have the SAME Hot Letters (final set positions) are given out, for example), it may be required that the contestant must have BOTH (or all three or more words) Hot Words' total letters COMPLETELY owned to qualify, if the probability to get one Hot Word is too high, OR it may be required that the Contestant land on the Million Dollar space during the game ALSO with the just ONE Hot Word gain of total letters to balance out the probability.
2. In the WinSpin™ the contestant must land on the Million Dollar space to win the Million Dollars. If there are 30 wedges (as preferred) and each wedge has three flipper pin positions then it is preferred that only ONE of the total 89 flipper positions may have the Million Dollar designation. See Win Spin above for more details.
3. Other requirements may be added or altered depending on the probability frequency the Show can afford to give that level of prize money out.
[0173] Note: All of the above steps may be altered, added to and modified to adjust the best and reasonable probabilities of balanced outcomes of win and loss in the Million Dollar space, as well in any part of WSW Game rules, steps and processes. The following are three representative embodiments of how an entire “show episode” of 30 minute duration (alike to many other game show durations) could be structured:
[0000]
Embodiment # 1 (Three Standard Segments have Three Modules each) Total time:
20:05
Segment I
05:30
Show Intro (logo, establishing studio shot, host walk-on, contestant intro)
00:50
First Round (Bronze, preferably) begins . . .
Game Module 1. Contestant #1 spins to select game, game is played
01:30
Game Module 2. Contestant #2 spins to select game, game is played
01:30
Game Module 3. Contestant #3 spins to select game, game is played
01:30
Segment Wrap-up
00:10
Segment II
05:30
Pic-in-a-Poke guest artist session (intensity relief)
00:50
Second Round (Silver, preferably) begins . . .
Game Module 4. Contestant #1 spins to select game, game is played
01:30
Game Module 5. Contestant #2 spins to select game, game is played
01:30
Game Module 6. Contestant #3 spins to select game, game is played
01:30
Segment Wrap-up
00:10
Segment III
04:35
Third Round (Gold, preferably) begins . . .
Game Module 7. Contestant #1 spins to select game, game is played
01:30
Game Module 8. Contestant #2 spins to select game, game is played
01:30
Game Module 9. Contestant #3 spins to select game, game is played
01:30
Segment Wrap-up
00:05
Segment IV
04:30
Funny Forge game-- comic relief session (audience participation)
01:00
Scramble For Your Life Part 1: Auction
01:30
Scramble For Your Life Part 2: Puzzle solving
01:00
Scramble For Your Life Part 3: Results and winner announced
00:20
Final Mystery Spin/Win Spin (for winner only-chance to multiply winnings,
00:20
get additional prize)
Closing
EMBODIMENT #1 (1EMB)
Synopsis
[0174] Of the three embodiments envisioned, the first embodiment (hereby known also as 1EMB) has the most cramped time scale, due to the inclusion of three rounds of three games each.
[0175] In the first segment, a standard opening sequence will be shown for every episode, including catchy theme music, an animated logo, an establishing shot of the interior of the studio, and a professional announcer inviting the audience to watch Wordsmith Wars. The host will walk on the set, briefly greet the audience, then proceed to briefly introduce the contestants or competitors. The 1EMB uses only 50 seconds for the entire introductory sequence, slightly more cramped than some of its industry competitors.
[0176] The host then briefly introduces the First Round (tentatively known as the Bronze Round, see *3), and instructs the first contestant (hereby known as Con1) to spin the WHEEL. Con1 spins the WHEEL, which (normally) determines which game module will be played. See *4. When the WHEEL stops spinning, the paddle/selector/pointer points to a particular WHEEL SEGMENT, which (normally) shows what game the three contestants or competitors will play.
[0177] There will be a large number of possible game modules for the WHEEL to select. The number of modules is expected to be at least 12, and will certainly be greater than the total number of modules that can be played in a particular episode. Though each module is distinctly different from each of the others, there is a common familiar “playability” and consistency among them. Each module is a distinct game unto itself, with simple, clear rules that need a minimum of explanation. *5. The monetary scoring of the module games is standardized and simple to understand. *6. The contestants or competitors play the game. For the 1EMB, each game module session will be played for a total of 90 seconds (including spinning the WHEEL and a brief introduction of the game module). Game modules will vary by content and method of play, but generally puzzles will be played, either turn-based, selection-based (CLICK SWITCH use *11), or real-time, until the time limit is reached. See *7 for a description of some sample games and how they are played.
[0178] When the time limit for the first game module is reached, the second contestant (Con2) spins the WHEEL and selects a module for the second game to be played. (Before this is done, the space(s) for the preceding game are removed from the wheel or covered up with new options. See *8). The host briefly explains the second game module, and the contestants or competitors play until the time is used up. This sequence will be used for all subsequent game modules that are played. In 1EMB the third contestant (Con3) spins for the third and final game module of the round. When the third game module is completed, the segment ends with a brief wrap-up by the host. Total length of the first segment in 1EMB is 5 minutes and 30 seconds. Then a standard commercial break is experienced. See *9 for more info regarding lengths of segments.
[0179] After the commercial break, Segment II begins. First up is the Pic-in-a-Poke session. The host briefly introduces a talented guest artist *10 who then begins to quickly sketch pictures for the contestants or competitors to guess. (It works like Pictionary). The monetary scoring will be the same as used in the first (bronze) round, see *6. The contestants or competitors will guess the pictures using their CLICK SWITCHES to be first to answer each puzzle. *11. Pic-in-a-Poke lasts 50 seconds in 1EMB.
[0180] After Pic-in-a-Poke, the host introduces the second (silver) round. The second round is played in the same fashion as the first, but the amount of money won for each correct answer is increased. *6. As for the first round, the second round of 1EMB has three game modules. After all three modules are played, the host wraps up the segment. This second segment is 5 minutes and 30 seconds long.
[0181] After the commercial break, Segment III begins. The host briefly introduces the third (gold) round, and play begins as Con1 spins the wheel to find out what the 7 th game module will be. Once again, the amount of monetary reward for each correct answer is increased from the Round 2 level. #6. Otherwise, the third round is played much the same as the first and second. The host wraps it up, and the segment ends. The length of the third segment 1EMB is 4 minutes and 35 seconds.
[0182] Segment IV begins with the funniest part of the show, Funny Forge. Here, an unusual word from the English language is presented, and each contestant must concoct a meaning for it. Then, the three concocted answers are read off by the host, along with a fourth answer—the correct one. The studio audience (and/or the television audience) then votes. A total of $5,000 worth of prize money (or a different amount) is assigned to the game. The studio audience's votes are recorded electronically and tallied for each answer. The prize money is proportionately split up for the three contestants or competitors according to how many votes their individual forged words received. The audience members who actually guess the correct definition of the word get to split the proportionate prize money for the correct answer. *1 *2
[0183] After Funny Forge, the climactic game “Scramble For Your Life” is introduced. The host, an accomplished auctioneer, introduces a category (i.e., Victorian Novel, or Presidential Quotes). Then the host reveals the scrambled puzzle on the Big Board SCREEN so the contestants or competitors see how many word blanks it has. All the words of the puzzle will be scrambled, but two or more words will be blanked out letter by letter, for the Hot Letters. *12. The host auctions off the words of the puzzle based on position. The contestants or competitors use their accumulated winnings to bid on being revealed privately (known only to the highest bidder) the positions of the words in the puzzle, *13, then the host auctions off the Hot Letters. *12.
[0184] When the auction is finished, the host announces that the contestants or competitors have one minute to solve the puzzle. The contestants or competitors use individual interactive electronic devices to solve the puzzles. *14. The words and letters they have won in the auction are properly placed in sequence on their own individual devices, possibly giving any particular contestant an advantage over the others, depending upon how many and what positions letters/words they gain. The first contestant to correctly solve the puzzle is the winner. The winner receives $25,000 plus his/her remaining accumulated winnings *15. The two contestants or competitors who do not win lose half their winnings (perhaps down to a predetermined level, such as $1,000, so no one leaves empty-handed). The results are tallied, the winner is announced.
[0185] The host then shows the winner to the wheel, which has been prepared specially for the bonus/final/Mystery Spin/Win Spin. The winner spins the wheel one more time to determine whether he or she will be able to multiply their total winnings by a factor of 1, 2, or 3, possibly receive additional non-monetary prizes, lose half their winnings, or possibly win the rare prize of one million dollars. *16
[0186] The host then closes out the show.
[0000]
Embodiment # 2 (2EMB) (Two Standard Segments have Two Modules each)
20:00
Segment I
05:10
Show Intro (logo, establishing studio shot, host walk-on, contestant intro)
01:00
First Round (Bronze?) begins . . .
Game Module 1. Contestant #1 spins to select game, game is played
02:00
Game Module 2. Contestant #2 spins to select game, game is played
02:00
Segment wrap-up
00:10
Segment II
05:10
Pic-in-a-Poke guest artist session (intensity relief)
01:00
Second Round (Silver?) begins . . .
Game Module 3. Contestant #3 spins to select game, game is played
02:00
Game Module 4. Contestant #1 spins to select game, game is played
02:00
Segment wrap-up
00:10
Segment III
04:15
Third Round (Gold?) begins . . .
Game Module 5. Contestant #2 spins to select game, game is played
02:00
Game Module 6. Contestant #3 spins to select game, game is played
02:00
Celebrity segment introducing remaining Hot Letters *17
00:10
Segment wrap-up
00:05
Segment IV
05:00
Funny Forge game-- comic relief session (audience participation)
01:00
Scramble For Your Life Part 1: Auction
01:30
Scramble For Your Life Part 2: Puzzle solving
01:00
Scramble For Your Life Part 3: Results and winner announced
00:30
Final Mystery Spin/Win Spin ™ (for winner only-chance to multiply winnings,
00:30
get additional prize)
Closing
00:30
UNUSED TIME AVAILABLE:
00:35
EMBODIMENT #2
Synopsis
[0187] The second embodiment (hereby known also as 2EMB) consists of three rounds of two games each.
[0188] In the first segment, a standard opening sequence will be shown for every episode, including catchy theme music, an animated logo, an establishing shot of the interior of the studio, and a professional announcer inviting the audience to watch Wordsmith Wars. The host walks on the set, briefly greets the audience, then proceeds to briefly introduce the contestants or competitors. The 2EMB uses 60 seconds for the introductory sequence, which is on par with its industry competitors.
[0189] The host then briefly introduces the First Round (tentatively known as the Bronze Round, see *3), and instructs the first contestant (hereby known as Con1) to spin the WHEEL. Con1 spins the WHEEL, which (normally) determines which game module will be played. See *4. When the WHEEL stops spinning, the paddle/selector/pointer points to a particular WHEEL SEGMENT or WEDGE, which (normally) shows what game the three contestants or competitors will play.
[0190] There will be a large number of possible game modules for the WHEEL to select. The number of modules is expected to be at least 12, and will certainly be greater than the total number of modules that can be played in a particular episode. Though each module is distinctly different from each of the others, there is a common familiar “playability” and consistency among them. Each module is a distinct game unto itself, with simple, clear rules that need a minimum of explanation. *5. The monetary scoring of the module games is standardized and simple to understand. *6. The contestants or competitors play the game. For the 2EMB, each game module session will be played for a total of 120 seconds (including spinning the WHEEL and a brief introduction of the game module). Game modules will vary by content and method of play, but generally puzzles will be played, either turn-based, selection-based (CLICK SWITCH use *11), or real-time, until the time limit is reached. The game modules will each include one Hot Letter given out to a player as they answer a question or puzzle correctly. *17. See *7 for a description of some sample games and how they are played. See *17 for a description of the Hot Letters system.
[0191] When the time limit for the first game module is reached, the second contestant (Con2) spins the WHEEL and selects a module for the second game to be played. (Before this is done, the space(s) for the preceding game are removed from the wheel or covered up with new options. See *8). The host briefly explains the second game module, and the contestants or competitors play until the time is used up. This sequence will be used for all subsequent game modules that are played. When the second game module is completed, the segment ends with a brief wrap-up by the host. Total length of the first segment in 2EMB is 5 minutes and 10 seconds. Then a standard commercial break is experienced. See *9 for more info regarding lengths of segments.
[0192] After the commercial break, Segment II begins. First up is the Pic-in-a-Poke™ session. The host briefly introduces a talented guest artist *10 who then begins to quickly sketch pictures for the contestants or competitors to guess. (It works like Pictionary). The monetary scoring will be the same as used in the first (bronze) round, see *6. The contestants or competitors will guess the pictures using their CLICK SWITCHES to be first to answer each puzzle. *11. Pic-in-a-Poke lasts 1 minute in the 2EMB.
[0193] After Pic-in-a-Poke, the host introduces the second (silver) round. The second round is played in the same fashion as the first, but the amount of money won for each correct answer is increased. *6. In 2EMB the second round begins with Con3 since Con1 and Con2 have already had a turn to spin the WHEEL and select a game module in the first round. After Con3's turn, Con1 takes his second turn, spinning the WHEEL to select the fourth game module. As in the first round, the second round of 2EMB has two game modules. After both modules are played, the host wraps up the segment. This second segment is 5 minutes and 10 seconds long.
[0194] After the commercial break, Segment III begins. The host briefly introduces the third (gold) round, and play begins as Con2 spins the wheel to find out what the 5 th game module will be. Once again, the amount of monetary reward for each correct answer is increased from the Round 2 level. *6. Otherwise, the third round is played much the same as the first and second. The host wraps it up, and the segment ends. The length of the third segment 2EMB is 4 minutes and 5 seconds.
[0195] *17. The Hot Letters obtained during the game modules are now complete. Now is the time to insert a 10-15 second prerecorded celebrity message introducing the remaining Hot Letters. Obviously, in prerecording the shot, there is no way to know ahead of time what the remaining Hot Letters will be, so the celebrity will point to the bottom of the screen and say that the contestants or competitors will need to bid on the following letters to complete their last puzzle. A different celebrity will be used each time, to keep the audience anticipation level high. The remaining Hot Letters will be revealed at the bottom of the screen when the celebrity makes the announcement. If this celebrity piece is inserted, then Segment III's time will be increased by the 10-15 seconds used.
[0196] Segment IV begins with the funniest part of the show, Funny Forge. Here, an unusual word from the English language is presented, and each contestant must concoct a meaning for it. Then, the three concocted answers are read off by the host, along with a fourth answer—the correct one. The studio audience (and/or the television audience) then votes. A total of $5,000 worth of prize money (or a different amount) is assigned to the game. The studio audience's votes are recorded electronically and tallied for each answer. The prize money is proportionately split up for the three contestants or competitors according to how many votes their individual forged words received. The audience members who actually guess the correct definition of the word get to split the proportionate prize money for the correct answer. *1 *2 Funny Forge is preferably allotted up to 1 minute of air time.
[0197] After Funny Forge, the climactic game “Scramble For Your Life” is introduced. The host, an accomplished auctioneer, introduces a category (i.e., Victorian Novel, or Presidential Quotes). Then the host reveals the scrambled puzzle on the Big Board SCREEN so the contestants or competitors see how many word blanks it has. All the words of the puzzle will be scrambled, but two or more or more words will be blanked out letter by letter, for the Hot Letters. *12, *17. The host auctions off the words of the puzzle based on position. The contestants or competitors use their accumulated winnings to bid on having revealed privately (known only to the highest bidder) the positions of the words in the puzzle, *13, then the host auctions off the Hot Letters not already assigned. *12, *17.
[0198] When the auction is finished, the host announces that the contestants or competitors have one minute to solve the puzzle. The contestants or competitors use individual interactive electronic devices to solve the puzzles. *14. The words and letters they have won in the auction are properly placed in sequence on their own individual devices, possibly giving any particular contestant an advantage over the others, depending upon how many and what positions letters/words they have gained. The first contestant to correctly solve the puzzle is the winner. The winner receives $25,000 plus his/her remaining accumulated winnings *15. The two contestants or competitors who do not win lose half their winnings (perhaps down to a predetermined level, such as $1,000, so no one leaves empty-handed). The results are tallied, the winner is announced.
[0199] The host then shows the winner to the wheel, which has been prepared specially for the bonus/final/Mystery Spin/Win Spin. (Or, as in current Wheel of Fortune, use a smaller separate wheel, a scale model, if you will, of the large one. Or use a rapidly-deployable insert system to instantly transform the wheel). The winner spins the wheel one more time to determine whether he or she will be able to multiply their total winnings by a factor of 1, 2, or 3, possibly receive additional non-monetary prizes, lose half their winnings, or possibly win the rare prize of one million dollars. *16
[0200] The host then closes out the show.
[0000]
Embodiment # 3 (3EMB) (Two Standard Segments have Three Modules each) total time
20:05
Segment I
07:10
Show Intro (logo, establishing studio shot, host walk-on, contestant intro)
01:00
First Round (Silver?) begins . . .
Game Module 1. Contestant #1 spins to select game, game is played
02:00
Game Module 2. Contestant #2 spins to select game, game is played
02:00
Game Module 3. Contestant #3 spins to select game, game is played
02:00
Segment Wrap-up
00:10
Segment II
01:30
Pic-in-a-Poke guest artist session (intensity relief)
01:30
Segment III
06:10
Second Round (Gold?) begins . . .
Game Module 4. Contestant #1 spins to select game, game is played
02:00
Game Module 5. Contestant #2 spins to select game, game is played
02:00
Game Module 6. Contestant #3 spins to select game, game is played
02:00
Segment Wrap-up
00:10
Segment IV
05:00
Funny Forge game-- comic relief session (audience participation)
01:00
Scramble For Your Life Part 1: Auction
01:30
Scramble For Your Life Part 2: Puzzle solving
01:00
Scramble For Your Life Part 3: Results and winner announced
00:30
Final Mystery Spin/Win Spin (for winner only-chance to multiply winnings,
00:30
get additional prize)
Closing
00:30
Unused Time:
00:10
EMBODIMENT #3
Synopsis
[0201] The third embodiment (hereby known as 3EMB) uses two main rounds of play, with three game modules per round.
[0202] In the first segment, a standard opening sequence will be shown for every episode, including catchy theme music, an animated logo, an establishing shot of the interior of the studio, and a professional announcer inviting the audience to watch Wordsmith Wars. The host will walk on the set, briefly greet the audience, then proceed to briefly introduce the contestants or competitors. The 3EMB uses 60 seconds for the introductory sequence, which is on par with its industry competitors.
[0203] The host then briefly introduces the First Round (tentatively known as the Silver Round, see *3), and instructs the first contestant (hereby known as Con1) to spin the WHEEL. Con1 spins the WHEEL, which (normally) determines which game module will be played. See *4. When the WHEEL stops spinning, the paddle/selector/pointer points to a particular WHEEL SEGMENT, which (normally) shows what game the three contestants or competitors will play.
[0204] There will be a large number of possible game modules for the WHEEL to select. The number of modules is expected to be at least 12, and will certainly be greater than the total number of modules that can be played in a particular episode. Though each module is distinctly different from each of the others, there is a common familiar “playability” and consistency among them. Each module is a distinct game unto itself, with simple, clear rules that need a minimum of explanation. *5. The monetary scoring of the module games is standardized and simple to understand. *6. The contestants or competitors play the game. For the 3EMB, each game module session will be played for a total of 120 seconds (including spinning the WHEEL and a brief introduction of the game module). Game modules will vary by content and method of play, but generally puzzles will be played, either turn-based, selection-based (CLICK SWITCH use *11), or real-time, until the time limit is reached. See *7 for a description of some sample game modules and how they are played. The game modules will each include one Hot Letter given out to a player as they answer a question or puzzle correctly. *17. See *7 for a description of some sample games and how they are played. See *17 for a description of the Hot Letters system.
[0205] When the time limit for the first game module is reached, the second contestant (Con2) spins the WHEEL and selects a module for the second game to be played. (Before this is done, the space(s) for the preceding game are removed from the wheel or covered up with new options. See *8). The host briefly explains the second game module, and the contestants or competitors play until the time is used up. This sequence will be used for all subsequent game modules that are played. In 3EMB the third contestant (Con3) spins for the third and final game module of the round. When the third game module is completed, the segment ends with a brief wrap-up by the host. Total length of the first segment in 3EMB is 7 minutes and 10 seconds. Then a standard commercial break is experienced. See *9 for more info regarding lengths of segments.
[0206] After the commercial break, Segment II begins. In 3EMB Segment II is only comprised of the Pic-in-a-Poke session. The host briefly introduces a talented guest artist *10 who then begins to quickly sketch pictures for the contestants or competitors to guess. (It works like Pictionary). The monetary scoring will be the same as used in the first (silver) round, see *6. The contestants or competitors will guess the pictures using their CLICK SWITCHES to be first to answer each puzzle. *11. Pic-in-a-Poke lasts 90 seconds in 3EMB, including segment wrap-up.
[0207] After the commercial break, Segment III begins. The host briefly introduces the second (gold) round, and play begins as Con1 spins the wheel to find out what the 4 th game module will be. The amount of monetary reward for each correct answer is increased from the Round 2 level. #6. Otherwise, the second round is played much the same as the first. As with the first round, the second round of 3EMB has three game modules. The host wraps it up, and the segment ends. The length of the third segment 3EMB is 6 minutes and 10 seconds.
[0208] *17 The Hot Letters obtained during the game modules are now complete. Now is the time to insert a 10-15 second prerecorded celebrity message introducing the remaining Hot Letters. Obviously, in prerecording the shot, there is no way to know ahead of time what the remaining Hot Letters will be, so the celebrity will point to the bottom of the screen and say that the contestants or competitors will need to bid on the following letters to complete their last puzzle. A different celebrity will be used each time, to keep the audience anticipation level high. The remaining Hot Letters will be revealed at the bottom of the screen when the celebrity makes the announcement. If this celebrity piece is inserted, then Segment III's time will be increased by the 10-15 seconds used.
[0209] Segment IV begins with the funniest part of the show, Funny Forge. Here, an unusual word from the English language is presented, and each contestant must concoct a meaning for it. Then, the three concocted answers are read off by the host, along with a fourth answer—the correct one. The studio audience (and/or the television audience) then votes. A total of $5,000 worth of prize money (or a different amount) is assigned to the game. The studio audience's votes are recorded electronically and tallied for each answer. The prize money is proportionately split up for the three contestants or competitors according to how many votes their individual forged words received. The audience members who actually guess the correct definition of the word get to split the proportionate prize money for the correct answer. *1 *2 Funny Forge is allotted 1 minute of air time.
[0210] After Funny Forge, the climactic game “Scramble For Your Life” is introduced. The host, an accomplished auctioneer, introduces a category (i.e., Victorian Novel, or Presidential Quotes). Then the host reveals the scrambled puzzle on the Big Board SCREEN so the contestants or competitors see how many word blanks it has. All the words of the puzzle will be scrambled, but two or more words will be blanked out letter by letter, for the Hot Letters. *12, *17. The host auctions off the words of the puzzle based on position. The contestants or competitors use their accumulated winnings to bid on having revealed privately (known only to the highest bidder) the positions of the words in the puzzle, *13, then the host auctions off the Hot Letters not already assigned. *12, *17.
[0211] When the auction is finished, the host announces that the contestants or competitors have one minute to solve the puzzle. The contestants or competitors use individual interactive electronic devices to solve the puzzles, preferably located at the top of their private podiums. *14. The words and letters they have won in the auction are properly placed in sequence on their own individual devices, possibly giving any particular contestant an advantage over the others, depending upon how many and what positions letters/words they have gained. The first contestant to correctly solve the puzzle is the winner. The winner receives $25,000 plus his/her remaining accumulated winnings *15. The two contestants or competitors who do not win lose half their winnings (perhaps down to a predetermined level, such as $1,000, so no one leaves empty-handed). The results are tallied, the winner is announced.
[0212] The host then shows the winner to the wheel, which has been prepared specially for the bonus/final/Mystery Spin/Win Spin. (Or, as in current Wheel of Fortune, use a smaller separate wheel, a scale model, if you will, of the large one. Or use a rapidly-deployable insert system to instantly transform the wheel). The winner spins the wheel one more time to determine whether he or she will be able to multiply their total winnings by a factor of 1, 2, or 3, possibly receive additional non-monetary prizes, lose half their winnings, or possibly win the rare prize of one million dollars. *16
[0213] The host then closes out the show. Segment IV is 5 minutes long.
[0214] *1 For example, suppose there are 500 people in the Studio Audience. Suppose the word “Glink” is introduced. Contestant #1 makes up the definition “A marsupial found in Indonesia.” Contestant #2 makes up the definition “A link of metal used to make chain mail armor.” Contestant #3's definition is “An anomaly in an overall weather pattern.” The real definition is actually “A sideways glance.” The host reads the four definitions to the audience, who then vote with their electronic tallying devices (attached to their seating). Suppose 119 people vote for Contestant #1's definition, 146 people for Contestant #2's definition, 93 for Contestant #3's definition, and 142 people vote for the correct definition. In this scenario, Contestant #1 would receive $1,190, Contestant #2 would receive $1,460, Contestant #3 would receive $930, and the 142 people in the audience who guessed the correct answer would each receive $10. (There is an option to add another portion to Funny Forge, where the contestants or competitors actually guess for the correct answer after the audience votes. This would be extra credit, or bonus reward to win.)
[0215] *2 In case one or more of the three contestants or competitors actually happens to write out a definition that is the correct answer, then they should get a higher prize (maybe $2,000 or so). Additional false answers should be ready for the host to use in the event that one or more contestants or competitors actually writes out the real definition. Or, alternatively, the host could simply mention that one (or more) of the contestants or competitors actually guessed the correct definition, and the audience could be allowed to vote from the remaining choices.
[0216] *3 Explanation of bronze, silver, gold rounds. These are simple graphic color and associated levels of play that apply to segments of the show that increase in value as the game modules' value scores become higher over time.
[0217] *4 Explanation of how spinning the wheel works, for determining the game modules to be played. Wheel is simply spun by contestants or competitors (or dice is rolled, or balls in cage are turned, or cards are turned over after shuffling) and the flipper indicator stops at wedge or wheel board segment to be played.
[0218] *5 Like most game shows, contestants or competitors will be adequately briefed and/or trained ahead of time before filming begins. They will be taught how to play each of the game modules, in case they happen to play any given one.
[0219] *6 Explanation of monetary scoring system for the module games.
[0220] Money award structure may be:
[0221] $500 (ish) per correct answer in the first round, and $1,000 per correct answer in the second round. (just double it for the second round) Potential to lose half or the whole amount for a wrong answer.
[0222] *7 Sample module games and how they are played: See “Grammar Hammer™”, My Times Crossword™”, “Smitherines™”, etc. above explanations.
[0223] *8 Description of how to change the WHEEL after a module game is selected and played. Repeat landing on the same game wedge INCREASE the value of that SAME game played again—OR, a new wedge can be laid over that already played wedge, or if the wedges are video screens, they can be easily changed into another different game module name to play.
[0224] *9 Lengths of various show segments can be altered relatively easily by taking alternative break points between game modules within a round, if necessary, to oblige established network formatting.
[0225] *10 Guest artists for Pic-in-a-Poke will be selected from the public through an internet audition system, followed up by personal auditions, or possibly “well-known” artists can be invited to draw for exposure of their works and name. They may be paid a fee, as well. Though a monetary reward system may or may not be in place for them, but their work will be exposed publicly, which is very valuable to them. It may be possible for them to have their website link on the WSW homepage for people to contact them afterward. Also, the artwork drawn for the show could be auctioned off on the internet to the highest bidder. It would be sensible to allow the artist to “finish off” each sketch before letting it be auctioned.
[0226] *11 Click switches are essentially of the type used on Jeopardy. They allow a contestant to establish their right to answer a particular question or puzzle.
[0227] *12 Hot Letters appear “electronically-spontaneously”, several hidden in possible word answers per game module, since NOT ALL words gained during a module will have a Hot Letter in them. When a particular answer is displayed on the SCREEN, if it a one of the words that contained a prior Hot Letter embedded before the show starts, one of its letters is highlighted in some fashion—The Hot Letter—and the host may point out the bonus letter transferred to the Big Screen under the name of the applicable contestant who won that letter. (or not, depending on necessity or convenience).
[0228] *13 The contestants or competitors use their accumulated winnings to bid on the positions of words in the Scramble For Your Life puzzle. Contestants or competitors possessing less than a certain amount (maybe $1,000) going into the Scramble For Your Life game will have their winnings boosted to that amount (i.e., $1,000). The point is to ensure that all three contestants or competitors are able to bid on the puzzle. They also bid on the Hot Letters that are not won in the preceding game rounds, as well as Key Phrase Words, as explained in the drawings and specification to follow.
[0229] *14 The Scramble For Your Life puzzle is solved by the individual contestants or competitors on their electronic devices. Detail exactly how this is done is explained in the drawings and specification to follow.
[0230] *15 Winning Scramble For Your Life determines the winner of the episode. It is theoretically possible that a different player could have a higher score than the winner. However, the non-winning players lose half their winnings anyway. The winner will have at least $25,000 going into the bonus/Mystery Spin/Win Spin, since that is the preferred, but not limited, amount the main game winner will earn.
[0231] *16 What it takes to win the $1,000,000 prize: It may be an option to include a single peg space (for example, a 30 wedge wheel would have “eighty-nine” peg spaces at three peg positions per wedge or wheel segment, on the Win Spin “overlay” in final round. There may be additional requirements, too, to make that probability lower so as not to make the show “go broke” by too many people winning that amount too often.
[0232] *17 The first six (or any designated amount suitable) HOT LETTERS are obtained during the six game modules (one or more per module). In each game module, one of the HOT LETTERS will be highlighted at random (or seemingly so) within an answer given to a puzzle. The contestant who gives the correct answer in which the HOT LETTER is revealed is given that HOT LETTER to keep. (it will be displayed on the board in such a way as to reveal that it belongs to them—IMPORTANT: It is the “position” of that Hot Letter won as it correctly is placed into the Hot Word(s) WITHIN the Key Phrase in the “Scramble For Your Life” round that is actually won. ALL Hot Letters won (just the letters, not the final position) will be known by ALL contestants or competitors, however). See Hot Letter explanation above for more details.
[0233] A 10-15 second prerecorded celebrity message after the final regular game module to introduce the remaining Hot Letters may be inserted in the game segment, which will be bid on. Obviously, in prerecording the shot, there is no way to know ahead of time what the remaining Hot Letter Letters will be, so the celebrity will point to the bottom of the screen and say that the contestants or competitors will need to bid on the following letters to complete their last puzzle (Scramble For Your Life). A different celebrity may be used each time, to keep the audience anticipation level high, although a good show host can engage audiences at a high level, as well. When “Scramble For Your Life” is played, each contestant will have all the HOT LETTERS he has won (both in the game modules, and the auction) inserted in his puzzle for him. More concise Rules are illustrated in text plus drawings within the following drawing pages herein.
[0234] The above summary is general and serves as an overview of the invention. Further features and modifications besides those summarized will be described in the following description. It should be obvious to one skilled in the present art to see possible general modifications that may be substituted for those employed to achieve the purposes of the present invention, while not departing from the spirit or scope of the present invention. In addition, further characteristics of the invention may be understood by the following description and drawings, the preferred embodiments of which are by way of example and non-limiting to the spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0235] FIG. 1 drawing illustrates the “Wordsmith Wars™” Game show embodiment in a TV Show standard, single game play screen stage setting.
[0236] FIG. 2 drawing illustrates the “Wordsmith Wars™” Game show embodiment in a TV Show stage setting that comprises both an audience viewing screen and another contestants or competitors' viewing screen.
[0237] FIG. 3 drawing illustrates the “Wordsmith Wars™” Game show optional chance selection means as a chance selection wheel having game module selectable wedges used preferably in a TV Show stage setting
[0238] FIG. 4 drawing illustrates the “Wordsmith Wars™” Game show optional chance selection means as a chance selection multi-sided large dice piece having game module selectable facets used preferably in a TV Show stage or game board setting
[0239] FIG. 5 drawing illustrates the “Wordsmith Wars™” Game show optional chance selection means as a chance selection deck of cards having game module selectable indicator faces used preferably in a board game
[0240] FIG. 6 drawing illustrates the “Wordsmith Wars™” Game show optional chance selection means as a chance selection balls within a rotating cage having game module selectable indicia on the ball faces used preferably in a TV Show stage setting
[0241] FIG. 7 drawing illustrates the “Wordsmith Wars™” Game show as being adapted into an internet electronic and interactive formats using an arrays various devices to support such distribution and game play
[0242] FIG. 8 drawing illustrates the “Wordsmith Wars™” Game show game module SmytheSpell™ having been selected and being played on the Big Board or Big Screen
[0243] FIG. 9 drawing illustrates the “Wordsmith Wars™” Game show game module Chime th' Rhyme™ having been selected and being played on the Big Board or Big Screen
[0244] FIG. 10 drawing illustrates the “Wordsmith Wars™” Game show game module Blazing Bellows™ having been selected and being played on the Big Board or Big Screen
[0245] FIG. 11 drawing illustrates the “Wordsmith Wars™” Game show game module Pic-in-a-Poke™ having been selected and being played on the Big Board or Big Screen
[0246] FIG. 12 drawing illustrates the “Wordsmith Wars™” Game show game module My Times Crossword™ having been selected and being played on the Big Board or Big Screen
[0247] FIG. 13 drawing illustrates the “Wordsmith Wars™” Game show game module Quotable Quotes™ having been selected and being played on the Big Board or Big Screen
[0248] FIG. 14 drawing illustrates the “Wordsmith Wars™” Game show game module Funny Forge™ having been selected and being played on the Big Board or Big Screen
[0249] FIG. 15 drawing illustrates the “Wordsmith Wars™” Game show game module Sudden Scrabble™ having been selected and being played on the Big Board or Big Screen
[0250] FIG. 16 drawing illustrates the “Wordsmith Wars™” Game show game module Pigeon Holes™ having been selected and being played on the Big Board or Big Screen
[0251] FIG. 17 drawing illustrates the “Wordsmith Wars™” Game show game module Smitherines™ having been selected and being played on the Big Board or Big Screen
[0252] FIG. 18 drawing illustrates the “Wordsmith Wars™” Game show game module Key Stokes™ having been selected and being played on the Big Board or Big Screen
[0253] FIG. 19 drawing illustrates the “Wordsmith Wars™” Game show game module Word Wedges™ having been selected and being played on the Big Board or Big Screen
[0254] FIG. 20 drawing illustrates the “Wordsmith Wars™” Game show game module Grammar Hammer™ having been selected and being played on the Big Board or Big Screen
[0255] FIG. 21 drawing illustrates the “Wordsmith Wars™” Game show game module Coal Pile™ having been selected and being played on the Big Board or Big Screen
[0256] FIG. 22 drawing illustrates the “Wordsmith Wars™” Game show game modules Pigeon Holes™, Zig Zap™, Blazing Bellows™ and Smythesaurus™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0257] FIG. 23 drawing illustrates the “Wordsmith Wars™” Game show game modules Free Key Phrase Word!™, Free Hot Letter!™, Vote Now! Audience Choice™ and Smythstery™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0258] FIG. 24 drawing illustrates the “Wordsmith Wars™” Game show game modules Scrabology™, Scrabulary™, Scrabography™ and Sudden Scrabble™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector elector means
[0259] FIG. 25 drawing illustrates the “Wordsmith Wars™” Game show game modules Key Stokes™, Chime th' Rhyme™, and Coal Pile™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0260] FIG. 26 drawing illustrates the “Wordsmith Wars™” Game show game modules Grammar Hammer™, Horseshoe Hunch™, and Blaze-a-Phrase™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0261] FIG. 27 drawing illustrates the “Wordsmith Wars™” Game show game modules Macro Morph™, Word Wedges™, and Noggle™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0262] FIG. 28 . drawing illustrates the “Wordsmith Wars™” Game show game modules Kaboom 25% OFF™ and My Time Crossword™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0263] FIG. 29 drawing illustrates the “Wordsmith Wars™” Game show game modules Smitherines™, Quotable Quotes™, and SmytheSpell™ as game module indicia upon a wedge for a Wordsmith Wars™ Chance Wheel module selector means
[0264] FIG. 30 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #1 live game episode flow process chart being divided into four uniquely arranged show segments
[0265] FIG. 31 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #1 continued live game episode flow process chart being divided into four uniquely arranged show segments
[0266] FIG. 32 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #2 live game episode flow process chart being divided into four uniquely arranged show segments
[0267] FIG. 33 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #2 continued live game episode flow process chart being divided into four uniquely arranged show segments
[0268] FIG. 34 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #3 live game episode flow process chart being divided into four uniquely arranged show segments
[0269] FIG. 35 drawing illustrates the “Wordsmith Wars™” Game show TV preferred embodiment #3 continued live game episode flow process chart being divided into four uniquely arranged show segments
[0270] FIG. 36 drawing illustrates the “Wordsmith Wars™” Game show embodiment in a standard game board format that would normally be play upon a table.
[0271] FIG. 37 drawing illustrates the “Wordsmith Wars™” Game show embodiment in an internet electronic screen game play format.
[0272] FIG. 38 drawing illustrates the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ three-part intro page being played on the Big Board or Big Screen
[0273] FIG. 39 drawing illustrates the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ Auction intro page being played on the Big Board or Big Screen
[0274] FIG. 40 drawing illustrates and describes the Auction Rules for the “Wordsmith Wars™” Game show game module Scramble for Your Life!™, and the Non-Positioned Hot Letters™ and Key Phrase Words™ Auction being played on the Big Board or Big Screen
[0275] FIG. 41 drawing illustrates the three contestants or competitors' “private” screens in the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ Scrambled Key Phrase, and the Non-Positioned Hot Letters™ and Key Phrase Words™ now being privately placed into final “blue” position (according the contestants or competitors letter and word “earlier game earnings”) on the Big Board or Big Screen
[0276] FIG. 42 drawing illustrates the three contestants or competitors' “private” screens in the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ Scrambled Key Phrase, and the ADDITIONAL (remaining) Non-Positioned Hot Letters™ now being privately placed into final “blue” position (according the contestants or competitors letter and word “successful bid earnings”) on the Big Board or Big Screen
[0277] FIG. 43 drawing illustrates the three contestants or competitors' “private” screens in the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ Scrambled Key Phrase, and the ADDITIONAL (remaining) Non-Positioned Key Phrase Words™ now being privately placed into final “blue” position (according the contestants or competitors letter and word “successful bid earnings”) on the Big Board or Big Screen
[0278] FIG. 44 drawing illustrates the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ part two “Puzzle Solving” on the Big Board or Big Screen
[0279] FIG. 45 drawing illustrates the three contestants or competitors' “private” screens in the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ on the Big Board or Big Screen, but hidden to them
[0280] FIG. 46 drawing illustrates the Win Spin™, the third and final part of the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ on the Big Board or Big Screen
[0281] FIG. 47 drawing illustrates both the Win Spin™ Bonus Wheel Overlay and Surprise Overlay for the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ on the Big Board or Big Screen
[0282] FIG. 48 drawing illustrates the Win Spin™ Bonus Wheel Overlay wedge option prize and chance outcomes for the “Wordsmith Wars™” Game show game module Scramble for Your Life!™ on the Big Board or Big Screen
[0283] FIG. 49 drawing illustrates the “Wordsmith Wars™” Game show main game module board template for the Wordsmith Wheel™
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0284] For the sake of repetition of all the content of the Summary, the reader is urged to study the terminology and function or processes, methods of the Summary to enhance understanding of the following Detailed Description. Noting FIG. 1 through FIG. 48 , particularly FIG. 1 , wherein a non-traditional stage floor 14 or game show venue stage 14 comprises a Wordsmith Wars™, aka., WSW (or other appropriately named game show name for the game invention disclosed herein) game board 1 , aka Big Board or main board 1 that may be fully or partially electronic in its graphics and of varying height, width or screen thickness. Said Big Board may be constructed of large screens that are “pieced” together in a grid network of screen that can be quite large in active color surface area, or it may be a huge projector screen, or series of projector screens. Said Big board 1 may include a name banner 2 area where the said game show name may be displayed. This optional stage set up, said non-traditional stage 14 of FIG. 1 may comprise a second game screen 25 supplied for contestants or competitors 18 and host only that has line-of-site path 26 unique to themselves. This is especially important to facilitate the audience as always being able to see both the big board screen and the contestants or competitors 18 ′ faces, which is unlike the standard game show stage wherein the cameras must constantly “pan and switch views” and film shoot back and forth the said game board 1 screen and then the contestants or competitors 18 directly face-on. This stage set up with a second screen arranges the contestants or competitors backs toward the said Big Board screen 1 and eliminates a significant amount of camera multi angles viewing and thus allows for a more rapid action play and excitement, with less interruption of this minimized panning and camera switching process described. Compare then the Stage Set Up of FIG. 1 with FIG. 2 , wherein is a typical stage Set Up that has only the one screen, the said Big Board 1 whereupon both the host's line of sight 27 and said contestants or competitors 18 ′ said line-of-site 26 is directed—as well as the audience view—both upon the same said Big Board 1 .
[0285] Within the confines of main board 1 over game theme 10 which graphically is depicted on a game board/screen background 9 is a game module name 3 and module game screen 4 that comprises and displays one of many graphically displayed game modules aka., game modules 3 , which modules are what may be called also “mini-games” on display, typically one said module 3 at a time, for contestants or competitors 18 , to play and both game host 17 with host assistant 16 to moderate, (all of them “show participants”), that said module being “Zig Zap™” 3 , presently on the said screen 4 . At or near said banner 2 is a display area 5 for contestant names 6 and winnings, including Hot Letter(s) won 7 , and additionally, Key Phrase Word (s) (final positions′) Won Space 8 or Icon Key Section 8 (comprising Icon Key Graphic 12 ) to display Key Phrase Word(s) 39 , FIG. 41 , out of Scrambled Key Phrase 39 , FIG. 41 , which said Key Phrase Words 39 are to be distinguished from “additional” Key Phrase Word(s) Won (their final positions) 45 in Scramble For Your Life bidding or auction process, illustrated and described in FIG. 40 .
[0286] Said WSW is played as contestant or host spins or activates chance selector means 19 , which in the preferred embodiment is a chance wheel board 19 , which may comprise a physical printed graphic overlay of wedge indicia or as a chance wheel game board 20 , may be large rotatable screen that may have any electronic graphic configuration programmed thereon, including a wedge pattern of game module indica. However, this said chance wheel may be substituted by another chance selector mechanism, as a multi-sided dice piece 19 a with game module indicia, as shown in FIG. 4 , or a Ball-in-cage selector 19 b , with indicia chance ball 62 , or even a chance selector means of a deck of cards 19 c with game module name indicia. However, the card deck would combine better with the WSW board game, as depicted in FIG. 36 , having board path 64 and board game path steps 33 , board game tokens 32 (Note: these tokens are like small donuts and could stacked upon themselves—like “Checkers” or they could be placed upon the neck of a “token pawn” (not shown). and board game awards 34, which in said FIG. 36 are shown to be “stackable” award discs 34 as collected and won throughout the WSW board game. The Board Game goal is entrance in to the center of the board win position 35 which is aka as the WordSmith Word Shop™, which signifies winning the game. It is to be noted that all of these above said “Chance Mechanisms” in FIG. 3 through FIG. 5 , in numbers 19 , 19 a 19 b , 19 c , respectively—including the said Board Game of FIG. 36 —may be readily and efficiently computerized and CONVERTED INTO ELECTRONIC mechanisms to be used in the electronic formats through for example, a WSW software version of the said WSW Game, discussed throughout this specification.
[0287] Further, the WSW game may be adapted beyond the above physical stage TV show environment to interactively engage audiences through any electronic formats that involve players watching or participating in the game through use of any of the broadcast mediums in which persons watch or play games. Noting FIG. 7 , TV and other potentially interactive communication media, through a WSW software version that may be play and/or downloaded such as over the internet or other communications networks such as desktop computer 30 , laptop computer 31 and small computer pad format 29 , smart phones 28 and many other “connected” devices, such as having an “app” for home audiences to play along during live broadcasts, all part of what is commonly being called the “Cloud” and “Internet of Things” or IoT are potential mediums for formats that may support and distribute the said WSW game. The said WSW computerized Game may be simply downloadable directly from the internet or through any physical storage media, such as optical storage disc, as DVD's or through magnetic media, as thumb drives, etc. . . . to where playing offline even alone or in person with another contestant/competitor is a preferred method of play, as well.
[0288] Note: All the software related to the electronic formatting and distribution of the said WSW Game, in all it various formats and possible modifications may include not only a unique said Board Game version FIG. 36 , but even any of the said chance selector means of said 19 , 19 a , 19 b , 19 c , may be converted in “digital animations” and incorporated through WSW computer related game software to enable a near as “realistic” as possible computerized experience on the said electronic devices of FIG. 7 , as possible.
[0289] Noting FIG. 37 , the format game module screen 3 on for example, a WSW software version is that of a typical computer pad screen such as an iPad® or Android® based tablet 29 or a said smart phone 28 game being played is Word Wedges™. Note “Wordsmith Wars™” logo 77 , which depicts two metal smiths pounding over one anvil as a potential Trademark establishing the heated competition to “pound out” words in order to be the wining game show contestant or winning player in the other game format venues discussed throughout this application.
[0290] However, in the preferred invention embodiment the said chance wheel 19 is spun by a contestant, or show host, by grasping the annular grasping member 21 , and turning the chance wheel game board 20 . It is preferred that the applicant's former wheel related inventions of applicant/inventor's U.S. Pat. No. 8,596,638 for “Rotatable Hand Grip System” and a second U.S. Pat. No. 8,690,154 entitled: “Safe and Novel, Lightweight Hand Grip Systems for Manually Spinning Gaming Wheels,” aka., “The New Wheel™ would be a preferred said chance mechanism 19 to assist in supporting the present WSW Game Invention of the subject application. Said Zig Zap 3 is the game module wedge 22 selected by chance as sector identification means or “flippers” 24 oscillate (click) against wheel pins 23 until coming to a stop. Game block build letters 11 of said Zig Zap 3 module are arranged on said screen 4 and contestant and audience may read “Quick Rules” 15 for each unique said game module 3 that is played. Note: It is obvious that “more than one said module 3 game can be played “simultaneously” and it may be that a preferred way to add intensity to the said WSWS game is to play more than one said game module concurrently.
[0291] As to the various said game modules 3 that may be played in WSW, FIG. 8 through FIG. 21 comprise sample said Big Board 1 screen shots of sample views of such game modules, the rules, structure and optional methods of play thoroughly discussed in the above Summary, in the Brief Description of the Drawings and throughout the text itself that is embedded in the said FIG. 8 through FIG. 21 's graphics. The Summary also discloses the response format, as it may be “Respond In Turn”, meaning contestants or competitors go on order of response opportunity. Other responses are “Click-In” meaning the first to click gets to guess answer. Scoring is also discussed in said Summary above and answers are recorded, nearly instantaneously processed by back stage judges (not shown) and standard value scoring or special scoring is discussed therein. Judges also provide validating means for evaluating the correctness of submitted answers, as well as typical timing means for limiting answer time limit duration, as well as other game module and segment duration.
[0292] FIG. 22 through FIG. 29 are simply detailed enlarged views of the said module names 3 affixed within the said game module wedges 22 . A full detailed view of the said chance wheel game board 20 , as a game module board template, is illustrated in FIG. 4 . It should be noted that each game module name is tailor designed in its text font chosen and refined to exemplify and capture the nature and character of the game being played. For example, Grammar Hammer™ has a text font and “feel” of very “orthodox” and “textbook” style “Old School” lettering, whereas Word Wedges™ has a more “block-type” feel to the shape and style of the font letters.
[0293] FIG. 39 through FIG. 45 illustrate and explain, with embedded text within the graphics, the Scramble For Your Life™ Game modules and round. “Scramble For Your Life” is introduced and the host, or an accomplished auctioneer, introduces a category (i.e., Victorian Novel), that would be in keeping with the said main theme 10 , such as “Old Europe”. Then the host reveals the scrambled puzzle on the Big Board so the contestants or competitors 18 see how many word blanks it has. All the words of the puzzle will be scrambled, but two or more or more words will be scrambled letter by letter in a ‘Remaining Hot Letter Line” 37 as in FIG. 41 and FIG. 42 . Note: These blank-letter words 40 , comprising a series of Hot Letter Block Blanks 41 , are also called Hot Words 40 and are in the CORRECT “word position” within the said Key Phrase—it is just that their letters are only partial or missing until filled in by the contestant.
[0294] Said ‘Remaining Hot Letter™ Line” 37 are “NON-positioned Hot Letters—and the contestants or competitors 18 are bidding for their CORRECT POSITION INSIDE the said Hot Words 40 (Note: These Hot Words™ MUST be discovered to complete the “unscrambling” of the Key Phrase, so they are highly important letters and words to secure in order to win the WSW Game—thus the bidding process becomes highly intensified to bid for and secure them). Early-in-game won said Hot Letters 7 are extracted out of certain “hot words” are “won” from the inception of play throughout which are ‘embedded” letters of correct words won during the early standard modules of the game—, until needed in final round(s) of game by a contestant. As well, word(s), and/or their correct word-in-phrase and “Hot Letters™-in-Hot-Word™” positions, in addition to points or money won, may also be won throughout play. These word and/or letter “threads,” are strings or a series of letters (that will be used to create words, later used in a final round, preferably called, “Scramble For Your Life™”) described further below. NOTE: These said Hot Letters in line 37 are those that remain AFTER the normal (earlier) game play said Hot Letters 7 are PRIVATELY distributed, as shown in FIG. 41 , for the Hot Letters. These said yet “un-assigned” Hot Letters 37 are distributed into the private contestant screens FIG. 41-FIG . 42 and FIG. 45 (in all three private screens group—all three screens seen by the audience but not by the contestants or competitors 18 , as per said Non traditional stage floor 14 that has TWO said game module screens, 3 , 25 , respectively) screens, referring to FIG. 42 , and are respectively Cindi's Hot Letters 42 (won in Auction/Bid), John's Hot Letters 43 (won in Auction/Bid), Kaitlin's Hot Letters 44 (won in Auction/Bid.
[0295] Noting FIG. 45 and number hot letters needing placement 79 , placed at the bottom of each contestant screen.
[0296] Note: It is PRECISELY the “pursuit” of this “thread” of said module earned Hot Letters 7 and said “bid-earned” Hot Letters 37 (literally, a two-phase pursuit) in order to fill in the said Hot Letters said Hot Words 40 of the said Key Phrase called Hot Words 40 (including blanks and partial filled Hot Letters) that creates such urgency and intensity of competition among the contestants or competitors 18 , resulting in the game WSW a major word-related learning tool for students of the English language, while providing riveting and entertaining engagement of the audience. But there is ALSO another auction. That “Key Phrase Word Bid” of FIG. 43 , where specific FINAL word positions 76 of the “remaining” (“remaining”, since the WSW Wheel has a FRRE Key Phrase Word wedge that may be won earlier in the game). The host auctions off the said Key Phrase Words 76 in their correct “FINAL” position designated ordinal (numerical) places within the “scrambled” phrase of the said Scramble For Your Life™ round or puzzle, namely: FIRST, LAST, SECOND, SECOND-TO-LAST, and MIDDLE (Note: if the word ends up in a non-dead middle, the MIDDLE word moves to the NEXT higher middle position. Note in FIG. 43 that Cindi won the FIRST word “AND” 45 and the word is assigned in her said Key Phrase screen 3 . John won “MY” 46 in the bid, the SECOND-TO-LAST word in the Key Phrase, and Kaitlin won “IF” the SECOND word. Continued bidding would continue until the MIDDLE word (“HE”—see: Correct Phrase word order “ANSWER” in FIG. 45 ) would be bid and won. Noting FIG. 45 and number hot letters needing placement 79 , placed at the bottom of each contestant screen.
[0297] The contestants or competitors 18 use their accumulated winnings to bid on privately revealed (known only to the highest/winning bidder) the words in the KEY Phrase round/puzzle, then the host auctions off the said Hot Letters, the said Remaining Hot Letter Line positions 37 , or this bidding order may be reversed.
[0298] When the auction is finished, the host announces that the contestants or competitors 18 have (up to) one minute to solve the puzzle. The contestants or competitors 18 use individual interactive electronic devices to solve the puzzles. It is preferred that each contestant have their own private electronic “computer work pad” 29 , or 31 , located at their podium—computer pads, such as #29 in FIG. 7 , or built right into the podium, itself (not shown). The words and letters they have won in the auction are properly placed in sequence on their own individual devices, with much highly likelihood of giving a particular contestant 18 an advantage over the others, depending upon how many and what positions letters/words they gain. The first contestant to correctly solve the puzzle is the winner. Once 15 seconds or so of the approximately one minute of Scramble time have elapsed, it is preferable that the WSW stage computers begin to electronically “POP” in HOT LETTERS into their correct place (simultaneously, AND in to ALL three contestants or competitors' 18 private screens) into the said Hot Words AND “POP” Key Phrase words into proper places, too. It is to be noted that all “WON” letters and words in this bidding process are in a preferably BLUE color, representing a FINAL correct position within the scrambled phrase, and all non-final positioned letters are in a RED color.
[0299] This electronic “Popping In” of Hot Letters and Key Phrase words accelerates so that by the time fifty seconds of the sixty seconds is up they are moving in quickly (ie. They are moved and TURN FROM A RED COLOR TO A BLUE COLOR, so that the contestants or competitors who has MORE of the actual scrambled Key Phrase words (and Hot Letters) in correct position will INEVITABLY BEAT the other contests 18 to the “finish” when the computer gets near the 50+ second duration with only seconds left. This creates a sort of “Fun Frenzy” that the audience will love to experience with the players since the audience is participating on their TV at home of even “interactively” in real time with the show through the internet. Note that “Post Bid” auction scores 78 are LOWER by the end of what may be an exciting, but brutal auction process, and may even go down to “0” after the fierce round of bidding for said Hot Letters and said Key Phrase Words. The two contestants or competitors 18 who do not win lose half their winnings. (perhaps down to a predetermined level, such as $1,000, so no one leaves empty-handed). The results are tallied, the winner is announced.
[0300] The winner receives, for example, a sizeable award of $25,000 plus his/her remaining accumulated winnings Noting FIG. 46 to FIG. 48 , it is preferred that the winner is then given an OPTION to try to INCREASE his or her monetary winnings or add to their monetary gain in The Win Spin™. However, there is a risk, since FIG. 47 and FIG. 48 illustrate Win Spin Wedge Options 49 that can cause a loss of 25% or even 50% of winnings (See “Kaboom! Wedges”). In the event the winner chooses to take the said Win Spin™, the host then shows the winner to the wheel, which has been prepared specially for the said Win Spin (aka. Bonus, or final, or Mystery Spin). In order to avoid having to provide another wheel for a “One Spin” bonus round (like, for example, Wheel of Fortune® having their additional mini wheel), it is preferable to have a mechanical overlay or Win Spin Bonus Wheel Overlay 48 which, if the Win Spin is played, a stage crew places over the original said chance wheel game board 20 . In addition, it is preferable to ALSO COVER the said Win Spin Bonus Wheel Overlay 48 with the Surprise Win Spin Overlay 50 , and then have the stage crew remove the said Surprise Overlay 50 AFTER the Win Spin of the winning contestant 18 to reveal the said prize or said loss possible. Based upon the said Win Spin Wedge Options 49 , the winner simply spins the wheel one more time to determine whether he or she will be able to multiply their total winnings by a factor of 1, 2, or 3, possibly receive additional non-monetary prizes, such as vacation cruises, lose half or one-fourth of their winnings, or possibly win the rare prize of one million dollars (wedge position not shown). The host then closes out the show.
[0301] Finally, 30 through FIG. 35 illustrate in a flow chart format the actual three sample embodiments of the how a typical 30 minute WSW Game Show episode would be segmented and arranged. The Summary above thoroughly discusses the same content in a simple text format that may be as or more preferable to the reader. Each flow “box” is self-explanatory simply by following the directional arrow through the segments. All three embodiments have four show segments, but the variation comes in as to how many said modules 3 , and for how long the modules are played within those segments that primarily makes the difference. The content of the show is still the same challenging, exciting WSW game content in all three said embodiments. It would be up to the show producer to find the right “sweet spot” as to how to most skillfully place commercial breaks and internal sponsorship ads within the industry standard of about 10 minutes of commercial related breaks for every 30 minutes of actual TV show or game show time events illustrated.
[0302] Other variations and modifications of the present invention will be apparent to those of ordinary skill in the art, and it is the intent of the appended claims that such variations and modifications be covered. The particular values, game modules, their order of play, duration and content and configurations discussed above can be varied, and are cited to illustrate representative embodiments of the present invention and are not intended to limit the scope of the invention. Other equivalent elements, methods and steps can be substituted for those described and illustrated herein; parts, steps and elements may be reversed, expanded, modified and certain features of the invention maybe used independently of the use of other features, all without departing for the spirit and scope of the invention, as defined in the subjoining claims. As well, it is contemplated that the use of the present invention can involve components, methods, processes and steps having different characteristics, different order or duration, even steps absent, as long as the principle, the presentation of various optional processes, methods or steps are followed, and thus fit within the spirit and scope of the claims. | Novel games, aka, “Wordsmith Wars™”, playable by one or more participants are disclosed comprising individual game modules that have assigned value accruing to the module-winning player(s), as a unique “game platform.” Modules are selected preferably by a chance or random indicator mechanism, such as a chance wheel, cards, dice, spinning globe with indicia, balls that roll into indented platforms out of cages, tubes or boards with indicia, as in Bingo game apparatuses, et al. These modules are collectively arranged or sequenced into game segments before or during the game play with a predetermined content and duration. The modules are thusly unified into a unique, composite, single “Wordsmith Wars™” game, which further may have a common theme(s) associated within the game content modules. As well, letter(s) or word(s), and/or their correct word or phrase positions, in addition to points or money won, may also be won throughout play. These word and/or letter “threads,” which are strings or a series of letters or words, may be collected by the contestants or competitors, then strategically used to advantage in a climactic final round or closing game module that may also include a strategic letter and/or word bidding process. The game may be adapted into a typical physical stage TV show or any electronic formats that involve players watching or participating in the game through use of any of the broadcast mediums in which persons watch or play games. A board game is also a preferred embodiment of the invention. Television game shows, including interactive TV, and in other interactive communication media, such as over the internet or other communications networks such as desktop and computer pad format, smart phones and many other “connected” devices, such as having an “app” for home audiences to play along during live broadcasts, all part of what is commonly being called the “Cloud” and “Internet of Things” or IoT are potential mediums for formats that may support and distribute the game. | 0 |
FIELD OF THE ART
This invention relates to a top rail for use with handrails, which is manufactured in an indefinite length, and is easily cut to the length required for a particular installation, is bent at the installation location under a force in excess of a predetermined value by a simple tool and is installed at the installation location as a single piece without joints. More particularly, this invention relates to such a top rail which is widely employed indoors and outdoors at locations such as walls adjacent staircases, windows, floors in hospitals and roofs in buildings and which comprises a top rail body formed of soft synthetic resin, semi-hard synthetic resin or synthetic rubber and a bendable metal core or cores embedded in the body.
BACKGROUND OF THE INVENTION
There are a variety of handrails for use on walls adjacent staircases, verandas, roofs, windows and floors in hospitals. As to handrails for staircases, there are a variety of types, such as those for use on straight staircases, those used on L-shaped staircases, those used on U-shaped staircases. Since those used on winding staircases and the length, slope and winding configuration of such staircases vary depending upon the type of buildings, the configuration of the staircase handrails also varies widely. Thus, the length and winding configuration of the top rails which form components of such handrails must be based upon the length and winding configuration of the installation areas, e.g. the staircases, verandas, windows or walls where such handrails are installed, and as a result, there are a great variety of top rails having varying configurations.
Therefore, it is quite difficult to produce a standardized top rail applicable to different installations at less expense on a large scale and at present, only a few varieties of standardized top rails are produced on a large scale to be used for a limited variety of buildings such as standardized apartment houses and buildings. Top rails for other types of buildings have to be produced in order to meet particular conditions at the installation area or a top rail portion for a straight portion of a particular handrail installation area and a top rail portion for a winding portion of the installation area must be produced separately. In the latter case, the top rail portion for the straight installation area portion is produced having a standardized length and as to the top rail portion for the winding portion of the installation area, a variety of top rail portions having different winding configurations are produced in advance and a particular one which is suitable to a particular installation is selected out of such top rail portions. The two part type top rail (straight and winding top rail portions) are connected together by means of welding or the like on at the installation site.
However, in the former case, since the particular top rail applicable to only a particular installation area is produced to order, the production cost of the top rail inevitably becomes high, and in the latter case, (two part rail), although the production cost of the top rail may be reduced somewhat, there are problems in precisely aligning the adjacent ends of the straight and winding top rail portions in abutment and also in giving pleasant appearance to the connection between the two top rail portions. Thus, the installation of these conventional top rails is a quite troublesome operation.
Therefore, in order to eliminate the problems inherent in the conventional top rails as described hereinabove, one object of the present invention is to provide a top rail for use with handrails which is produced with an indefinite length and is cut to the length of particular installation area, bent in conformity with the configuration of the installation area and attached to the installation area as a single piece without joints or the use of any connector means.
Another object of the present invention is to provide a top rail for use with handrails which can be produced in a continuous operation at reduced expense and which can be easily attached to an installation area in a simpler operation.
SUMMARY OF THE INVENTION
Thus, according to the present invention, there has been provided a top rail for a handrail which comprises a resilient top rail body and a bendable metal core or cores embedded in the body extending in the longitudinal direction thereof. The top rail body is formed of resilient material such as soft synthetic resin, semi-hard synthetic resin or synthetic rubber, which is bendable and free of any surface deformation such as creases when bent and the bendable metal core is bendable under a force in excess of a predetermined value and maintains the top rail body in its bent condition when bent together with the body. With the above-mentioned construction and arrangement of the components of the top rail of the present invention, the top rail body is produced in an indefinite length by extrusion, cut to the length of a particular installation area installation located, bent by hand in conformity with the configuration with the turns of the installation area by any suitable means, such as by hand, tool or machine, and then attached to the installation area as a single piece without joints. Thus, the top rail for a handrail of the present invention can be produced regardless of the configuration of the installation area and standardized for production at low cost on a large scale. In addition, the connection operation which hithertofore has substantially reduced the top rail installation efficiency is eliminated and the overall installation operation efficiency is substantially enhanced. Furthermore, the appearance of the installed top rail is also substantially improved. The prior art top rail for handrails was required to be cut in conformity with the configuration of the staircase and butt-joined accomodate the winding configuration of the staircase, that is the shorter top rail portion and longer straight top rail portion were required to be prepared separately and then butt-jointed together accommodate the winding of the installation area. On the other hand, the top rail for handrails of the present invention can be freely bent in both the horizontal and vertical directions and also twist and attached to the installation area as one piece along the entire extent of the installation area while being bent in the required orientation. Particularly, since the top rail of the present invention can be freely bent in the required orientation as stated above and does not require the connection operation of the prior art, the top rail can be installed by an unskilled person and is applicable to general domestic use.
Also in the top rail of the present invention, since the top rail body is formed of soft synthetic resin, semi-hard synthetic resin or synthetic rubber, the body can be colored to a desired color in harmony with the environment to thereby enhance its decorative effect and give a soft feeling to the hand.
Furthermore, according to one embodiment of the present invention, the bendable metal core is formed of an elongated solid steel bar and a lubricant applied about the surface of the core and soft or semi-hard synthetic resin is extruded about the lubricant applied surface to form the top rail body. By this construction, when the top rail is bent, the body and metal core slide relative to each other whereby the top rail can be easily bent by hand or a simple tool and installed at the installation area with sufficient strength and rigidity.
Furthermore, according to the present invention, the bendable metal core is in the form of an elongated solid bar formed of aluminum or aluminum alloy, and adhesive is applied about the surface of the core and soft or semi-hard synthetic resin is extruded about the adhesive applied surface to form the top rail body. By this construction, even when the bending stress on the bendable metal core is less than that on the steel core, since the top rail body and bendable core are integrally united together, in spite of the fact that the top rail can be easily bent by hand or a simple tool, the top rail when installed at the installation area has sufficient strength and rigidity.
In the present invention, when the top rail body is formed having an ordinary cross-sectional dimension and the bendable metal core is in the form of a solid round bar formed of steel, aluminum or aluminum alloy, the relationship between the diameter (d) of the bendable metal core and the number of cores employed (n) can be expressed by the following formula: ##EQU1## wherein the unit of d is mm, n is an integer and σ is the maximum bending stress (Kg/mm 2 ) of the material. When the bendable metal core is formed of steel, σ=-75 Kg/mm 2 , when the core is formed of hard aluminum wire, σ=20-30 Kg/mm 2 and when the core is formed of soft aluminum wire, σ=5.5-9.5 Kg/mm 2 .
The bendable metal core is, of course, not limited to the above-mentioned ones and the material, cross-sectional configuration, cross-sectional dimension, number of cores and arrangement of the cores within the top rail body are determined depending upon conditions required for the top rail in the installation of the top rail, that is, whether the top rail is required to be bent either in the transverse or longitudinal direction or both in the transverse and longitudinal directions. The metal core is preferably bendable by hand or at least by the use of a mechanical means such as a roll bender or vice and capable of maintaining the top rail in its bent state against the inherent resilience of the top rail body after the bending of the top rail.
The top rail body preferably has an outer peripheral circumference on the order of 60-200 mm (the corresponding transverse width dimension being on the order of 20-50 mm) and may have any cross-sectional configuration such as a true circle, oval, ellipse or triangle having rounded corners, or rectangle or rhomb, provided that the top rail is easily grasped and positively held when the user places his hand or hands on the top rail from above. The top rail itself may be provided on the surface thereof with a thin layer of hard synthetic resin to enhance the appearance of the top rail or the body may be formed with a plurality of circumferentially spaced ribs extending in the longitudinal direction thereof to enhance the grasping property of the top rail. Alternatively, the top rail body may be provided with a suitable luminous member extending in the longitudinal direction thereof.
The top rail has a unitary construction comprising the bendable metal core about which the top rail is extruded and is produced having a length longer than at least the installation area where the top rail is to be installed. The top rail is wound into a roll as necessary, but the winding of the top rail may be performed within the elastic deformation limits of the bendable metal core as the well as plastic deformation limits. In the latter case, it is preferable that the top rail which has the tendency to return to the rolled condition even after the top rail has been stretched in the installation thereof is straightened by any suitable straightening means to remove the tendency.
When the top rail is to be attached to an installation area such as walls adjacent staircases, verandas, roofs, windows or floors in buildings by means of brackets, erect railing members or support bars, the top rail is cut to the length of the installation area and bent in conformity with the configuration of the installation area.
The above and other objects and attendant advantages of the present invention will be more readily apparent to those skilled in the art from a reading of the following detailed description in conjunction with the accompanying drawings which show preferred embodiments of the invention for illustration purpose only, but not for limiting the scope of the same in any way.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertically sectional view of a preferable or first embodiment of a top rail for handrails of the invention;
FIG. 2 is a plan view of the top rail of FIG. 1 showing the top rail in its rolled condition; FIG. 3 is a fragmentary perspective view of the top rail of FIG. 1 showing the top rail in its transversely bent condition;
FIG. 4 is a fragmentary perspective view of the top rail of FIG. 1 showing the top rail in its longitudinally bent condition;
FIG. 5 is a fragmentary perspective view of the top rail of FIG. 1 showing the top rail in its transversely and longitudinally bent condition;
FIG. 6 is a perspective view of the top rail of FIG. 1 showing the top rail as being attached to building walls above a winding staircase by the use of brackets;
FIG. 7 to 9 are plan, side elevational and cross-sectional views, respectively, of one of the brackets as shown in FIG. 6;
FIG. 10 is a vertically sectional view of a second embodiment of the top rail for handrails of the invention;
FIGS. 11 to 14 are perspective views showing second, third, fourth and fifth embodiments of the top rail for handrails of the invention showing the embodiments as being employed in connection with different types of staircases;
FIGS. 15 and 16 are perspective views of a sixth embodiment of the top rail for handrails of the invention showing the top rail as being attached to walls adjacent a veranda and floor, respectively;
FIGS. 17 and 18 are perspective views of a seventh embodiment of the top rail for handrails of the invention showing the top rail as being employed in the handrail on a roof and that of a spiral staircase in a building, respectively;
FIGS. 19(a) to (f) are schematic views of modified top rail bodies of the invention;
FIGS. 20(a) to (d) are vertically sectional views showing variation in the number and arrangement of bendable metal cores employed in different embodiments of the top rail for handrails of the invention;
FIGS. 21 and 22 are fragmentary perspective views in vertical section of modifications of the top rail for handrails of the invention; and
FIG. 23 is a vertical sectional view of a further modification of the top rail for handrails of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in detail referring to the accompanying drawings.
BENDING TEST OF BENDABLE METAL CORES
On the assumptions that (1) when a person of average body weight of about 60 Kg leans on a top rail of a handrail, a load of about 50 Kg is applied to the top rail, (2) that when the person of average body-weight places both of his hands on the top rail and tries to bend the top rail by applying substantially his whole body-weight to the top rail with a space of 30 cm maintained between the hands, a load of 50 Kg is applied to the top rail and (3) that a pair of fulcrums spaced from each other by 30 cm are provided at the areas on the top rail where his both hands are placed, a load of 50 Kg can be applied to the top rail at an intermediate area between the fulcrums to determine whether the bendable metal core or cores embedded in the top rail would bend or not under such conditions of use. Bending tests were made on various metal cores. The materials of the metal cores are steel equivalent to SS 30B - D or SS41B - D falling under Material Standard JIS G 3123, mild aluminum wire equivalent to A1070, A1050, A11100 or A1200 falling under Material Standard JIS H 4040 and hard aluminum wire equivalent to A5052, A5056 or A6063 falling under Material Standard JIS H 4040, respectively. The wire may be a solid bar of truly circular cross section. The relationship between the number and diameter of bendable metal cores at the critical bending was examined and the examination results are shown in the following Table.
______________________________________ Number of coresMaterial 1 2 3______________________________________Steel 7.9-9.8 mm 6.3-7.9 mm 5.5-6.9 mmMild aluminum 15.9-19 mm 12.6-15.1 mm 11-13.2 mmWireHard aluminum 10.8-12.3 mm 8.6-9.8 mm 7.5-8.6 mmWire______________________________________
Taking the results of the tests into consideration the applicant has manufactured for trial various top rail bodies such as top rails which are easily bent by hand and can be installed by bending them manually, top rails which can be bent by hand, but require a vise or the like tool when they are installed especially while being bent in the longitudinal direction, and top rails which cannot be bent by hand and installed by bending them by the use of a tool such as vise or machine such as a roll bender. The top rails were employed in connection with walls adjacent staircases, verandas, roofs, windows or in buildings or the like structures. Embodiments of top rails for handrails of the invention will now be described.
FIRST EMBODIMENT
As shown in FIG. 1, Vinyl chloride (containing 50 parts of plasticizer) is extruded so as to form a top rail body 1 of elliptical cross section having a vertical dimension of 40 mm and a horizontal dimension of 20 mm. In the extrusion of the top rail body 1, a bendable metal core 2 is integrally embedded in the center of the top rail body 1 extending in the longitudinal direction of the body. The metal core 2 is formed of a solid rectangular hard aluminum bar having a vertical dimension of 9 mm and a horizontal dimension of 6 mm to provide the top rail A. The top rail A is then rolled by a winding machine into a roll having the outer diameter of 80-100 cm which is within the elastic deformation limit of the bendable metal core 2 as shown in FIG. 2. The top rail A can be bent not only in the transverse direction as shown in FIG. 3, but also in the longitudinal direction as shown in FIG. 4. Furthermore, the top rail A can be bent in both the transverse horizontal and longitudinal directions as shown in FIG. 5. The bending can be easily performed by hand.
When the top rail A is to be installed on the walls adjacent a winding staircase 3 which is commonly provided in general residential houses as shown in FIG. 6, the top rail A is first cut off the roll to a length suitable to the installation area 4 on the walls and the cut top rail is then manually bent in conformity with the contour of the installation area 4 in the longitudinal and transverse directions. In the bending operation, the top rail A is attached to the installation area 4 by means of brackets 5 secured to the area 4 at a uniform spacing of 600 mm from one edge to the opposite edge of the installation area 4.
As more clearly shows in FIGS. 7 through 9, the bracket 5 employed in this embodiment comprises a base 6 adapted to be secured to the installation area 4 prior to the installation of the top rail A to the walls and an arm 7 adapted to be secured to the back of the top rail A prior to the installation of the latter. A hole 9 extends through a lower portion of the arm 7 and the base 6. Aligned bores 8 and 9 extend through an upper portion of the base 6 and a lower portion of the arm 7, respectively, and a tapping screw 10 is passed consecutively through the bores 9 and 8 and driven into the installation area 4 to secure the top rail A to the area 4.
Although the top rail A is easily bent by hand in both the transverse and longitudinal directions in conformity with the contour of the installation area 4 and secured to the installation area by means of the screws which extend through the brackets 5 disposed at the uniform spacing of 600 mm along the area 4 and are driven into the installation area, the top rail is imparted sufficient strength and rigidity when secured to the installation area.
SECOND EMBODIMENT
As shown in FIG. 10, vinyl chloride (containing 50 parts of plasticizer) is extruded so as to form a top rail body 1 of elliptical cross-section having a vertical dimension of 40 mm and a horizontal dimension of 20 cm. In the extrusion of the top rail body 1, two bendable metal cores 2 are integrally embedded with a vertical space of 25 mm maintained therebetween to form a top rail A of indefinite length. The metal core 2 is formed of a solid truly circular cross-section steel bar having a diameter of 5 mm and anticorrosion oil applied to the surface thereof. As in the case of the first embodiment, the second embodiment can be easily manually bent not only in the transverse direction, but also in the longitudinal direction because the oil on the surface of the bendable metal cores 2 causes the synthetic resin top rail body 1 and metal cores 2 to be easily displaced relative to each other.
When the second embodiment of top rail A is to be installed on building walls adjacent a substantially L-shaped staircase 12 having a landing 11 in an intermediate position between the upper and lower ends of the staircase as shown in FIG. 11, the top rail A is first cut to the length of the installation area 4 of walls and then bent in conformity with the contour of the installation area 4, that is, the top rail A is bent substantially in the longitudinal direction at points P at the beginning and terminal ends of the landing 11 and then bent at substantially right angles at point H positioned between points P in the transverse direction and the thus bent top rail A is secured to the installation area 4 by means of the brackets (not shown) in the same manner as described in connection with the first embodiment.
THIRD EMBODIMENT
Although the third embodiment is substantially similar to the second embodiment as shown in FIG. 10, the third embodiment of top rail A has two hard aluminum bar cores 2 of truly circular cross section having a diameter of 6 mm. The third embodiment is also easily bendable by hand both in the transverse and longitudinal directions.
When the third embodiment of top rail A is to be installed on inner walls adjacent a building U-shaped staircase 14 having a landing 13 as shown in FIG. 12, the top rail A is first cut to the length of the installation area 4 of the inner walls and the cut top rail A is bent at points P at the beginning and terminal ends of the landing 13 in the longitudinal direction, and at point H between points P by 180°. The thus bent top rail is secured to the installation area 4 by means of the brackets 5 in the same manner as described in connection with the first embodiment.
Although the third embodiment is substantially similar to the second embodiment, the third embodiment is formed of extruded vinyl chloride (containing 34 parts of plasticizer) and has two spaced solid steel bar cores 2 of truly circular cross section having a diameter of 6 mm embedded therein and anticorrosion oil applied to the surface thereof integrally embedded therein. Although the third embodiment of top rail A may with a great deal of effort be manually bent at normal temperature in both the longitudinal and transverse directions the third embodiment encounters difficulties in installing the top rail on the installation area 4 while bending the same manually. However, experiments have shown that if the rail top is heated to about 50° C. by means of suitable means such as by pouring hot water at 88° C. or applying a heater bag containing hot water against the areas of the top rail where the top rail is bent, the top rail can be relatively easily bent by hand.
When the fourth embodiment of top rail A is to be installed on the top of a staircase partition wall 15 as shown in FIG. 13, the top rail A is cut to the length of the installation area 4 on the top of the partition wall 15. The cut top rail A is first bent by hand at point H on the top rail A in the transverse direction while being heated to about 50° C. and then attached to the upper ends of a plurality of erect support members 16 secured to the installation area 4 in a uniformly spaced relationship. Different from the foregoing embodiments, the fourth embodiment of top rail A is secured to the installation area 4 with the longer dimension of the elliptical cross-section of the top rail lying horizontally.
FIFTH EMBODIMENT
Although the fifth embodiment is substantially similar to the fourth embodiment, the fifth embodiment of top rail A is formed by extruding vinyl chloride (containing 50 parts of plasticizer) having an indefinite length. The fifth embodiment of top rail A is bent by hand easier than the fourth embodiment of the top rail, in both the longitudinal and transverse directions, but the fifth embodiment of the top rail is not bendable to such a degree that the top rail can be attached to the installation area 4 while being bent by hand.
When the fifth embodiment of top rail A is to be attached to the installation area 4 on walls adjacent a straight building staircase 18 having a landing 17 as shown in FIG. 14, the top rail A is first cut to the length of the installation area 4 and then attached to the installation area 4 while being bent in the longitudinal direction in conformity with the winding contour of the installation area 4 on the walls by the use of a simple tool such as a vice or the like and brackets 5 as shown in FIGS. 7 to 9.
SIXTH EMBODIMENT
Although the sixth embodiment is substantially similar to the foregoing embodiments with respect to appearance and shape, the top rail of the sixth embodiment is formed by extruding vinyl chloride (containing 50 parts of plasticizer) and has two spaced solid hard aluminum bar cores 2 of truly circular cross section having a diameter of 5 mm incorporated therein. Furthermore, the top rail body 1 and bendable metal cores 2 are secured together by means of adhesive. Although the sixth embodiment of top rail A can be easily bent by hand in the transverse direction and the metal cores 2 are easily bendable, since no relative displacement occurs between the top rail body 1 and bendable metal cores 2, the strength and rigidity of the top rail is substantially improved and the top rail can not be bent by hand in the longitudinal direction.
When the sixth embodiment of top rail A is to be attached to a veranda handrail as shown in FIG. 15, the top rail A is first cut to the length of the installation area 4 on the handrail and the cut top rail is bent in the transverse direction in conformity with the winding contour of the installation area 4 and attached horizontally to the upper ends of a plurality of spaced erect railing bars 21. The opposite ends of the top rail A are suitably anchored to walls (not shown).
When the sixth embodiment of top rail is to be attached to walls adjacent a floor 22 in a hospital or the like, the top rail A is first cut to the length of the installation area 4 of the walls and the cut top rail is then attached to the installation area 4 by means of the brackets 5 as shown in FIGS. 7 to 9 while being bent by hand in conformity with the winding of the installation area 4.
Since the sixth embodiment of top rail itself has sufficient strength and rigidity in the longitudinal direction, the top rail is not required to be bent in the longitudinal direction. Thus, it has been found that the sixth embodiment is advantageously employed in connection with indoor and outdoor structures such as varanda, roof and window handrails.
SEVENTH EMBODIMENT
The seventh embodiment is similar to the foregoing embodiments with respect to appearance, but the top rail A of this embodiments uses two solid steel bar cores of indefinite length and of truly circular cross section having a diameter of 10 mm, which cannot be bent by hand. When the seventh embodiment of top rail A is to be attached to the installation area 4 on the roof 23 of a building as shown in FIG. 17, prior to the installation, the top rail A is cut to the length of the installation area and the cut top rail A is previously bent in the longitudinal direction in conformity with the winding of the installation area 4 in a factory or at the installation location by the use of a bending machine or tool, and attached horizontally to the upper ends of a plurality of spaced erect support bars 24 at the installation area 4 by means of connectors 25 of substantially T-shaped cross section.
The seventh embodiment of top rail A may be wound into a roll of a predetermined diameter prior to the attachment thereof to the installation area 4. When the top rail A is to be attached to walls adjacent a spiral staircase 26 as shown in FIG. 18, the top rail is unwound from the roll and then cut to the length of the installation area 4 on the staircase. The cut top rail A is then bent in both the longitudinal and transverse directions in conformity with the winding of the installation area 4 and attached to the upper ends of a plurality of erect support bars 27 which form a part of the staircase handrail. In this embodiment, if the top rail A is wound into a roll having a winding radius corresponding to the width of the stairs, the top rail A can be quite easily attached to the installation area.
In the various embodiments as described hereinabove, as shown in FIGS. 1 and 10, the top rail body 1 of elliptical cross section of the top rail A has one or two bendable metal cores 2 integrally embedded therein extending in the longitudinal direction. However, the present invention is not limited to such an arrangement of the components. The top rail body 1 may have various cross-sectional configurations such as true circle, ellipse having rounded corners, rhomb, triangle, modified ellipse tapering toward one end, oval and rectangle having an arcuate recess on one longer side as shown in FIGS. (a), (b), (c), (d), (e) and (f), respectively, for example. When the top rail body has a relatively large diameter, the rail body is formed hollow, having an opening extending in the longitudinal direction. As to the bendable metal core 2, one bendable metal core 2 may be eccentrically embedded in the top rail body A extending in the longitudinal direction of the body as shown in FIGS. 20 (a) and (b), for example. Alternatively, three bendable metal cores 2 having the same diameter (FIG. 20 (c)) or two bendable cores 2a having a larger diameter and two bendable metal cores 2b having a smaller diameter (FIG. 20 (d)) may be employed to thereby impart the top rail with rigidity against bending in either the longitudinal or transverse direction or in both directions. Furthermore, taking the rigidity against bending in the longitudinal or transverse direction provided by the metal core or cores into consideration, the configuration of the top rail body is not limited to the ellipse or true circle as seen in the foregoing embodiments, but may be an other configuration. The bendable metal core 2 may be formed hollow within the scope of the invention. Furthermore, in the manufacturing the top rail A, if the top rail body 1 and bendable metal core or cores 2 are designed so that the material or resin of the top rail body is present about the metal core or in a substantially uniform thickness then a defect or defects which may otherwise occur on the surface of the top rail body 1 due to uneven pressure distribution in the resin caused by uneven thickness in the moulding of the top rail body can be eliminated.
In the foregoing embodiments, although the body 1 of the top rail A is formed of one type of material and has a smooth surface, the present invention is not limited to such a construction of the top rail body. For example, the top rail body 1 may be surrounded by a thin film 28 formed of hard synthetic resin different from that of the body 1 as seen in FIG. 21 or a luminous meterial 29 can be integrally applied to the top of the top rail 1 extending in the longitudinal direction of the body so that the luminous meterial 29 emits light during night hours to thereby indicate the position of the top rail A, as seen in FIG. 22. Alternatively, the surface of the top rail body 1 is provided with a concave-convex design 30 extending in the longitudinal direction thereof to thereby enhance the decorative effect of the top rail body and ensure a positive grasp on the top rail, as shown in FIG. 23.
APPLICATION IN INDUSTRY
In addition of the application of the top rails of the invention as handrail components on staircases, verandas, windows and roofs in buildings and as wall railing means or guard rails on walls adjacent floors in hospitals, the top rails of the invention can be employed as handrails or guard rails on tracks for large size machines, accommodation ladders on ships and aircrafts and baggage elevators.
While various embodiments of the invention have been shown and described in detail it will be understood that these are for the purpose of illustration only and are not to be taken as a definition of the scope of the invention, reference being had for this purpose to the appended claims. | A top rail for handrails comprises a top rail body formed of soft synthetic resin, semi-hard synthetic resin or synthetic rubber and having a bendable metal core incorporated therein extending in the longitudinal direction thereof. The bendable metal core is bendable under a force in excess of a predetermined value and maintains the top rail body in its bent position when the core is bent together with the body. The bendable metal core can be the form of an elongated solid steel bar, to which a lubricant has been applied to the surface thereof and soft or semi-hard synthetic resin is extruded about the lubricant applied surface to form the top rail body. The bendable metal core can also be in the form of an elongated solid aluminum or aluminum alloy bar, to which is applied adhesive about the surface thereof and soft or semi-hard synthetic resin is extruded about the adhesive applied surface. | 8 |
This invention relates to a packing gland assembly for a movable shaft, including a shutdown packing gland.
The packing gland assembly of this invention is designed particularly for use with a wellhead flow control device for a producing oil well, where oil is produced from a formation of asphaltic crude which includes highly toxic gases such as hydrogen sulphide, and where the polished rod of a sucker rod string passes through the flow control device.
Since the release to the atmosphere of a very small amount of such toxic gases may be very dangerous, it is important that the packing gland assembly for such wellhead flow control device provide an effective dynamic packing to seal the reciprocating polished rod, and also an effective static packing for sealing the idled polished rod in the event of leakage at the dynamic packing, and to enable repair or replacement of the dynamic packing.
An object of this invention is to provide a novel packing assembly for a movable shaft, including a dynamic shaft packing and a static shutdown packing.
Another object of this invention is to provide such a packing assembly wherein the dynamic packing may be repaired readily while the shutdown packing is effective to seal the shaft.
A further object of this invention is to provide such novel packing assembly including external operator means for the shutdown packing.
Still another object of this invention is to provide such novel packing assembly which is readily removable from the support housing, and wherein the several packing glands of the assembly are readily disassembled for repair, with the polished rod in place.
A still further object of this invention is to provide such packing assembly including a shutdown packing gland wherein the packing components are removable from either end of the gland body.
Another object of this invention is to provide such packing assembly wherein the packing material for the shutdown packing gland is fabricated as an integrated packing body.
A further object of this invention is to provide such packing assembly wherein the shutdown packing is adapted to be closed by external power means.
These objects are accomplished in a packing assembly for a movable shaft which projects from a housing to be sealed. The assembly includes a gland body having threaded means at its proximal end for sealing attachment to the housing, and providing a first packing chamber confronting the shaft adjacent the proximal end. A first annular packing body is disposed in the first packing chamber. An elongated tubular mandrel surrounds the shaft with its proximal end disposed within the gland body for compressing the first packing body within its packing chamber. The gland body provides a second packing chamber confronting the mandrel adjacent to its proximal end; and a second annular packing body is disposed in the second packing chamber. A packing cap threadedly mounted on the distal end of the gland body effects the compressing of the second packing body within its respective chamber. The mandrel provides a third packing chamber adjacent to its distal end, confronting the shaft. A third annular packing body is disposed in the third packing chamber; and a packing cap threadedly mounted on the distal end of the mandrel effects compression of the third packing body within its chamber. A coupling means is provided between the gland body and the mandrel for effecting axial compression of the mandrel relative to the body for compressing the first packing body.
The novel features and the advantages of the invention, as well as additional objects thereof, will be understood more fully from the following description when read in connection with the accompanying drawings.
DRAWINGS
FIG. 1a is a view of the lower portion of a flow control device, partially in elevation and partially in axial section;
FIG. 1b is a view of the upper portion of the flow control device of FIG. 1a, partially in elevation and partially in section, including a packing assembly according to the invention;
FIG. 2 is a detail view of a shutdown packing body for the packing assembly of FIG. 1b; and
FIG. 3 is a view, similar to that of FIG. 1b, illustrating an alternative form of packing assembly according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the drawings packing gland assemblies, according to the invention are illustrated as subassemblies for a wellhead flow control device in association with the polished rod of a well pump. Referring to FIG. 1a, a wellhead flow control device 20 is mounted on a wellhead 11 by a coupling assembly 12 which consists of a lower flange 13, an upper flange 14 and a coacting ring seal 15. The wellhead 11 may consist, for example, of a casing, a production casing bowl, well tubing, or other member; and the lower flange is attached thereto by means of welding, for example. The flanges clamp the ring seal by means of peripherally spaced nut-bolt assemblies 16. The upper flange is threaded internally for suspending a string of well tubing 17. The flow control device is designed for use with the polished rod 18 of a well pump.
The principal components of the flow control device are a valve body consisting of a lower valve body 21 and an upper valve body 22, a vertically reciprocible closure assembly in the form of a ram 23, an operator sleeve 24 for coupling and reciprocating the closure ram relative to the valve body, and a polished rod packing assembly 25 at the upper end of the ram for providing a gas tight seal between the ram 23 and the polished rod 18. The valve body, particularly the upper valve body 22, includes a ram packing gland 26 for providing a gas tight seal between the ram and the valve body. The lower valve body defines a valve seat for the packing plug assembly associated with the closure ram.
The lower valve body 21 includes a lower externally threaded nipple 30 for engagement with the upper flange 14 of the coupling assembly, and an upper externally threaded nipple 31 for threaded engagement with the upper valve body, the nipples being axially aligned and the body providing an axial chamber for receiving the ram 23 and also for the passage of the polished rod. This lower valve body is provided with transverse internally threaded ports for the attachment of pipes defining a flow line 32 and a sampling line 33. The body chamber defines an upward facing annular valve seat 34. The pipes for the flow line and sampling line open to the upper cylindrical chamber 38 above the valve seat 34.
The closure ram 23 consists of a generally cylindrical body 40, having an axial bore dimensioned for free sliding reciprocation of the polished rod 18. The body has an upper, externally threaded nipple 41 for attachment of the rod packing assembly 25. The ram body has a principal outer diameter dimensioned for a free sliding fit with the cylindrical chamber portion 38 of the lower valve body. An annular packing plug 42 is secured to the lower end of the ram body. The packing plug is retained on the ram body by an axially split annular retaining ring 46, retained to the body by tie rods 47.
The upper valve body 22 is a generally cylindrical sleeve having internal threads at its lower end for joining it to the lower valve body 21, and having internal and external threads at its upper end. The principal internal diameter of the sleeve 22 is larger than that of the body chamber 38 and of the ram body 40 to accommodate the ram packing gland 26 operative between the valve body and the ram body. This ram packing gland includes an annular packing material 52, and an externally threaded packing nut 54 threaded into the upper end of the sleeve 22. The exposed upper end of the packing nut is provided, at its outer periphery, with a plurality of peripherally spaced indentions 55 to enable the rotation of the packing nut without disassembly of the flow control device.
The operator sleeve 24 is a generally cylindrical member having internal square threads throughout most of its length for coaction with the external square threads on the upper end of the upper valve body 22. The operator sleeve is coupled to the ram body by means of a thrust coupling 60, which transfers axial thrust forces from the operator sleeve to the ram body. Rotation of the operator sleeve is effected by an operator handle 65, in the form of an elongated bar extending through transversely aligned holes in the operator sleeve.
To enable tightening of the packing nut 54, of the ram packing gland, the operator sleeve is provided with several axially and rotationally spaced access holes 67. These access holes are disposed generally in the area of the exposed portion of the packing nut 54, when the valve is open, to enable rotation of the packing nut by engaging the indentions 55 with a suitable tool through an access hole.
A safety vent passage is provided in the lower valve body 21 above the valve seat. This consists of a vent passage including an internally threaded bore opening to the exterior wall for receiving a rupture disk and vent fitting 58 for connecting a vent conduit to the valve housing.
The flow control device 25, which has been described briefly herein, is the subject of a separate copending patent application of the inventor.
FIGS. 1b and 2 of the drawing illustrate one preferred form of rod packing assembly 25 according to the invention, which includes a packing leak safety shutdown system. FIG. 1b illustrates portions of the flow control device 20 including the operator sleeve 24 and associated operator handle 65, and the nipple 41 at the upper end of the ram body 40. The packing assembly 25 is secured to the nipple 41 of the ram by means of a union consisting of a union body 101 threaded onto the ram nipple, a union ring 102 and the externally threaded lower flange of a packing gland body 103. A mandrel 104 is a generally tubular member having a lower or proximal reduced diameter portion dimensioned to be received within the gland body, and having an enlarged upper or distal portion defining a gland body for the rod packing gland.
The packing assembly 25 includes three packing glands, a static shutdown packing gland, a static mandrel packing gland, and a dynamic rod packing gland.
The mandrel is the operator for the shutdown packing gland which consists of the following components. A rod guide bushing 106 is an axially split sleeve having its proximal end confined within a recess in the ram nipple 41. This bushing is fabricated from a suitable bearing metal, and functions in part to guide and center the polished rod 18 relative to the ram 40 and to the packing assembly 25. The distal end of this bushing is provided with an internal, inwardly converging conoid surface defining a packing wedge; and this distal end is received within the lower end of the gland body 103. The bushing 106 is provided with notches 107 to enable prying of the bushing segments from the nipple 41. A packing body 108 is confined between the packing wedge and an upper split packing ring 109, which define the packing chamber. The packing ring is engaged by the proximal end of the mandrel 104.
The packing body 108 may be fabricated from any suitable material such as metallic wool, metallic felt or metallic tape, and/or ceramic fibers, which will act as a bulk sealing material under the extant conditions and which is chemically inert with respect to hydrogen sulfide or other corrosive gases. This packing body is preferably formed into a unitary body of defined shape. FIG. 2 is a detail view of this packing body 108, illustrating the shape which includes an upper cylindrical portion and a lower external conoid which coacts with the conoid surface of the packing wedge. In preferred form the packing body may be fabricated in the form of a one piece spiral, as illustrated in FIG. 2, so that it may be assembled around the polished rod 18. In assembled relation, as seen in FIG. 1b, the packing body will not be maintained in engagement with the rod, but is a standby shutdown packing to be employed, for example, in the event of a leak in the rod packing to be described. In this event the mandrel 104 will be moved downward to effect radially inward compression of the packer body by coaction with the conoid of the packing wedge. This seating of the body will occur only after reciprocation of the polished rod is stopped.
The mandrel packing gland includes a packing chamber 110 disposed in the distal end of the gland body 103, a split lower packing ring 111, gland packing material 112, a split upper packing ring 113, a split pusher sleeve 114 and a packing cap 115 threadedly coupled to the gland body 103. The packing rings and pusher sleeve are preferably formed as diametral halves to enable assembly around the polished rod 18. The packing material 112 may be a wrap-around packing or other suitable gland packing material.
The rod packing gland consists of the gland body and packing chamber defined by the distal end of the mandrel 104, a lower metallic, split packing ring 116, gland packing material 117, an upper metallic split packing ring 118, and a split guide bushing 119 functioning as a pusher sleeve retained within the upper gland cap 120. Again, the packing rings and pusher sleeve are preferably formed as diametral halves to enable assembly around the polished rod 18. The gland cap 120 is threadedly coupled to the upper end of the mandrel 104. This rod packing gland is subject to considerable wear because of reciprocation of the rod; and the packing material and packing rings should be chosen for wear resistance as well as for sealing against the leakage of toxic gases. Suitable material for this packing gland may be a strand of the above described material identified as metallic materials. The guide bushing 119 functions as a centering bushing for centering the rod relative to the packing assembly at the upper end, and is preferably fabricated from a suitable bearing material resistant to corrosive gases and fumes.
The gland cap 120 is provided with a suitable vent passage and sniffer fitting 121 for connecting the upper end of the rod packing to a suitable gas detector for the purpose of warning and/or for automatic control of the safety shutdown mechanism.
The safety shutdown mechanism consists of a pair of oppositely disposed, double acting, hydraulic cylinders 124, connected between lower and upper yokes 125 and 126 mounted respectively on the union body 101 and the mandrel 104. The lower yoke 125 is seated against the lower face of the union ring 102 by a nut 127. The upper yoke 126 is seated against the upper face of a flange 128 of the mandrel by a nut 129. It will be seen then that the double acting hydraulic cylinders 124 function as part of the safety shutdown system. An automatic control may respond to detection of a leak at the sniffer fitting 121 and effect automatic operation of the cylinders to move the upper yoke 126 downward and effect compression of the packing body 108 against the polished rod 18. Such automatic control would effect simultaneous shutdown of the pump and accompanying reciprocation of the polished rod. This enables safety shutdown of the system and prevents any leakage of gas until the rod packing gland can be suitably adjusted or repaired.
FIG. 3 illustrates a modified form of rod packing assembly according to the invention, wherein the rod shutdown packing gland is operated manually rather than by hydraulic power means. This assembly is shown mounted on the same ram body 40 and ram nipple 41; and the components of the assembly which are identical to those described above are identified by the same reference numbers, and the components which are modified but equivalent to those described above are identified by the same reference numbers with the subscript a. This assembly is secured to the nipple 41 by means of a union consisting of a union body 101a threaded onto the ram nipple, a union ring 102, and the externally threaded lower flange of a packing gland body 103a. The gland body is provided with a short length of internal threads 105 intermediate its ends. The mandrel 104a is a generally tubular member having a lower or proximal reduced diameter portion dimensioned to be received within the gland body, and having an enlarged upper or distal portion defining a gland body for the rod packing gland. The proximal end of the mandrel is provided with external threads for coaction with the threads 105 of the first named gland body. The packing assembly 130 also includes three packing glands: a static shutdown packing gland, a static mandrel packing gland, and a dynamic rod packing gland.
The mandrel 104a is the operator for the shutdown packing gland which consists of the components previously described including the wedge ring 106 and the packing body 108. Again, this shutdown packing is engaged by the proximal end of the mandrel 104a, through the upper packing ring 109, and the packing body 108 is compressed through rotation of the mandrel 104a and the operation of the threads 105. The packing body 108 has the same configuration and construction as that previously described, and functions in the same manner.
The mandrel packing gland, disposed in the packing chamber 110 at the distal end of the gland body 103a, also includes the same components including the packing body 112. Similarly, the rod packing gland consists of the same components including the packing body 117 and the guide bushing 119, and functions in the same manner. The gland cap 120 is provided with a suitable vent passage and sniffer fitting 121 for connecting the upper end of the rod packing to a suitable gas detector; and for this embodiment the gas detector will trigger a suitable warning device such as an audible or visble signal device or both; and this will alert the operator personnel to close the shutdown gland by rotating the mandrel 104a.
OPERATION
The operation of the above described packing assemblies from the standpoint of the packing functions, is believed to be apparent from the foregoing description; and the following is a discussion of maintenance and repair operation.
In order to disassemble the packing assembly 25 from the ram body 40, it is first necessary to disconnect the power cylinders 124 from either or both of the yokes 125 and 126. The nut 127 is then loosened to release the yoke 125 from the union body 101; and the union ring 102 may then be loosened to release the gland body 103 along the remainder of the assembly to be slipped upward on the polished rod 18. Preferably the rod packing gland cap 120 would first be loosened to reduce the friction of the packing body 117 on the polished rod.
Should the rod guide bushing 106 require replacement, the union body 101 may be unthreaded from the ram nipple 41, allowing the removal and replacement of the split sleeves of this bushing.
Should the shutdown packing require replacement, the split members of the packing wedge 106 may be removed from the gland body by engaging a prying tool in the notches 107; and the packing body 108 and packing rings 109 may then be pushed from the lower end of the gland body either by the mandrel 104 or by another suitable implement.
With the shutdown packing components removed, removal of the components of the mandrel packing are also readily accomplished after first separating the gland cap 115.
For removing the components of the rod packing, the gland cap 120 is first unthreaded and separated from the mandrel, and the mandrel may then be separated from the gland body 103. After removal of the split guide bushing halves 119, the packing body 117 and packing rings 116 and 118 may be removed by a suitable elongated pushing tool which may be passed through the clearance space between the mandrel and the shaft 18.
The packing assembly is designed so that the dynamic rod packing may be removed and replaced while the shut down packing is effective to seal the rod 18. This involves unthreading of the gland cap 120, removal of the guide bushing halves 119 and removal of the upper packing ring halves 118 and of the packing body 117 from the top of the assembly. While this packing removal and replacement is more difficult, it can be accomplished with safety.
An important feature of this invention is the construction of a packing assembly, for association with a movable rod or shaft such as the polished rod of a well pump, which facilitates the maintenance and/or repair of the several packing glands of the assembly and therefore minimizes unnecessary down time.
Another important feature of the invention is the provision of a packing assembly including a dynamic rod packing gland and a static shutdown packing gland for the rod, wherein the shutdown packing may be operated by external power means in the event of leakage detected at the dynamic gland.
Another feature of the invention is the configuration of the wedge-shaped packing chamber for the packing material of the shutdown packing gland, and of the wedge-shaped configuration of the packing body coacting with that chamber.
Still another important feature of the invention is the provision of the guide bushing 106 consisting of split members seated within ram nipples to center the polished rod relative to both the ram and the attached packing assembly. A related advantage is the provision of the prying notches 107 which coact with the union structure to enable ready separation of the packing assembly from the ram, and the ready removal of a worn guide bushing with a prying took, utilizing the prying notches.
While preferred embodiments of the invention have been illustrated and described, it will be understood by those skilled in the art that changes and modifications may be resorted to without departing from the spirit and scope of the invention. | A gland body is coupled at its proximal end to a supporting housing by means of a union. A first packing chamber, for a static shutdown packing, is formed at the proximal end of the gland body, with a wedge ring forming the base of the chamber. The wedge ring has a beveled surface diverging outwardly from the base; and a packing body has a complementary beveled surface confronting the wedge ring. A mandrel having a reduced diameter proximal end is received within the gland body for urging the first packing toward the wedge ring. A second packing chamber is formed at the distal end of the gland body confronting the mandrel; and a packing cap threaded onto the distal end of the body compresses the second packing body to seal the mandrel and gland body. The distal end of the mandrel is enlarged to form a third packing chamber confronting the shaft for receiving a third packing body being a dynamic packing for the reciprocating shaft. A gland cap threaded onto the distal end of the mandrel compresses the third packing body. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/754,010, filed Dec. 23, 2005.
TECHNICAL FIELD
[0002] The present invention relates to providing air flow to a vehicle brake drum during operation of a vehicle such as a truck, bus and trailer, and, in particular, to enhancing the ventilation of a vehicle brake drum having vent holes.
BACKGROUND OF THE INVENTION
[0003] The prior art includes brake drums for vehicles, including medium and heavy-duty trucks, trailers and buses. In order to slow or stop a moving vehicle, the braking mechanism is activated to urge the brake shoes and brake lining into engagement with the friction surface of the brake drum. The frictional engagement of the brake lining with the brake drum causes the vehicle to slow or stop. However, in the process, the kinetic energy of the moving vehicle is converted into heat. Further, the frictional engagement causes wear on the brake lining which produces debris in the form of brake dust. Over time, a substantial amount of brake dust may accumulate within the brake drum and surrounding area. The accumulation of brake dust impairs the performance of the brake system, such as reducing the effectiveness to dissipate heat, and creating noise during operation of the brake system. Still further, road debris enters the brake drum and further impairs performance of the brake drum.
[0004] The prior art includes various means for providing and enhancing cooling and ventilation to the brake drum, in order to remove the heat, debris and lessen noise. For example, U.S. Pat. No. 3,127,959 is directed to a cooling device for brake drums and shoes. The cooling device is installed within the brake drum. In particular, the cooling device includes a disc, the body of which is provided with a plurality of vanes which form air circulating blades when the disc is rotated. The disc is placed over the outer diameter of the wheel hub. The brake drum is then installed and receives the disc within a cavity formed by the brake drum. A magnet secured to the disc draws and holds the disc axially of the drum by magnetic force on the hub flange. U.S. Pat. No. 4,989,697 is directed to a cooling, cleaning and drying means for brake drums. In particular, a generally circular elongated flexible air scoop strip is provided and includes mounting holes and outwardly protruding air scoops. The strip is mounted within the brake drum and secured in place via bolts which extend through the mounting holes and through the brake drum.
[0005] The prior art also includes cooling devices which are installed on an exterior surface of the brake drum. For example, U.S. Pat. No. 2,896,749 discloses a brake drum cooling device having a plurality of ring segments joined together at their ends by means of turnbuckles. The turnbuckles serve to clamp the segments against the outer surface of the flange of a brake drum. U.S. Pat. No. 2,659,459 discloses a brake cooling ring which is secured to the outer surface of the brake drum via bolts which extend from the hub and through the brake drum.
[0006] It is also known to provide full cast transit brake drums with vent openings.
[0007] While advancements have been made to address the foregoing and other related problems, there still exists a need for further improvements.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a brake drum having improved ventilation.
[0009] It is a feature of the present invention to provide improved cooling features.
[0010] It is a further feature of the present invention to provide a brake drum with improved cleaning capability.
[0011] It is still a further feature of the present invention to provide a brake drum having features which reduce the tendency for certain operational noise.
[0012] It is still a further feature of the invention to provide a device which may be retrofitted to brake drums to enhance the ventilation of the brake drum.
[0013] It is still yet a further feature to provide a ventilation device which may be installed on a brake drum, regardless of whether the brake drum is to be installed on the left or right side of a vehicle.
[0014] The present invention therefore provides a brake drum having a cylindrical main body portion, a brake drum mounting flange portion, a brake drum transition portion, the brake drum transition portion extending between the cylindrical main body portion and the mounting flange portion, the transition portion having at least one vent opening, and an air scoop secured at the vent opening, whereby rotation of the brake drum and air scoop induces air movement within a brake drum cavity defined by the main body portion.
[0015] The present invention also provides a brake drum comprising a cylindrical main body portion, a brake drum mounting flange portion a brake drum transition portion, the brake drum transition portion extending between the cylindrical main body portion and the mounting flange portion, the transition portion having an outer surface and at least one vent opening; and an air scoop secured at the vent opening, the air scoop includes a louver opening and extends outwardly from the outer surface of the brake drum transition portion, whereby rotation of the brake drum and air scoop induces air movement within a brake drum cavity defined by the main body portion.
[0016] The present invention further provides a brake drum comprising a cylindrical main body portion defining a brake drum cavity, a brake drum mounting flange portion, a brake drum transition portion, the brake drum transition portion extending between the cylindrical main body portion and the mounting flange portion, the transition portion having an outer surface and a plurality of vent openings, and an air scoop secured at each vent opening and which extends outwardly from the outer surface of the braked drum transition portion, each air scoop defines a louver opening which faces the angular direction of drum rotation, an air channel in fluid communication with the louver opening and the brake drum cavity, and a deflection surface located in the air channel, the deflection surface positioned to re-direct air movement entering the louver opening at an angular direction, to a generally radial and inboard direction, whereby rotation of the brake drum and air scoop induces air movement within the brake drum cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows a perspective view of a brake drum having vent holes in accordance with the present invention.
[0018] FIG. 2 shows a partial cross sectional view of the brake drum of FIG. 1 .
[0019] FIG. 3 shows a perspective view of the brake drum of FIGS. 1 and 2 , wherein an air scoop has been installed at one of the air vents.
[0020] FIG. 4 shows a partial side view of the brake drum of FIG. 3 , with the air scoop installed in accordance with the present invention.
[0021] FIG. 5 shows a perspective view of the air scoop shown in FIGS. 3 and 4 , in accordance with the present invention.
[0022] FIG. 6 shows a partial side view of a brake drum, for use at the front of a vehicle, having the air scoop of FIG. 5 installed in accordance with the present invention.
[0023] FIG. 7 shows a second embodiment of the present invention, wherein an air scoop is installed on a brake drum for use at the front of a vehicle.
[0024] FIG. 8 is a perspective view of the air scoop shown in FIG. 7 , in accordance with the present invention.
[0025] FIG. 9 is a third embodiment of the present invention and it shows a partial view of a mounting flange portion of a brake drum for use at the front of a vehicle, in accordance with the present invention.
[0026] FIG. 10 shows a perspective view of the air scoop of FIG. 9 , in accordance with the present invention.
[0027] FIG. 11 is a fourth embodiment of the present invention and shows a partial perspective view of a mounting flange of a brake drum for use at the front of a vehicle, in accordance with the present invention.
[0028] FIG. 12 shows a partial side view of the mounting flange of FIG. 11 , having the air scoop in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] FIG. 1 discloses a two-piece composite brake drum 10 . The brake drum shown in FIG. 1 is designed for installation at the rear of a vehicle. Although FIG. 1 shows a rear two-piece composite brake drum, it will become apparent, from the further description, that the present invention is not limited to a two-piece composite drum, nor a rear drum. In fact, the present invention relates to brake drums in general. The particular brake drum shown in FIG. 1 includes a cylindrical main body portion or a steel shell portion 12 having a ribbed portion 14 and a squealer band 16 . A mounting flange portion 18 is also shown and includes a plurality of lug bolt openings 20 and a pilot hole 22 . The mounting flange portion also includes a transition portion 24 having a plurality of notches 26 . The mounting flange portion attaches to the cylindrical main body portion with a transition portion whereupon the notches form a plurality of vent openings 28 .
[0030] FIG. 2 shows a partial cross sectional view of the brake drum of FIG. 1 . FIG. 2 more readily shows the ribbed portions, and the squealer band. A brake liner portion or friction surface 30 is also shown. The mounting flange portion and steel shell portion form a brake drum cavity 32 .
[0031] FIG. 3 is a perspective view of the brake drum shown in FIGS. 1 and 2 . An air scoop 34 is shown mounted at one of the vent openings in accordance with the present invention. Final assembly of the two-piece composite brake drum in accordance with the present invention would normally include an air scoop at each of the vent openings.
[0032] FIG. 4 is a partial side view of the brake drum of FIG. 3 . The side view of the air scoop 34 is shown at the top left of the figure.
[0033] FIG. 5 is a perspective view of the air scoop 34 shown in FIGS. 3 and 4 . The air scoop includes a generally flat side wall 36 having a bottom edge 38 , side edges 40 and an upper edge 42 . The upper edge defines a curved or concave profile. A curved or concave back wall 44 extends from a first longitudinal side 46 at a substantially right angle from the upper edge. A curved or webbed side wall 48 extends from a second longitudinal edge 50 of the back wall at a generally inclined angle and in a radial direction and towards the outboard side of the air scoop. The webbed side wall includes a narrow portion 52 which extends laterally in opposite directions in a diverging manner so as to form opposing wide end portions 54 . The narrow portion extends further radially inward than does the opposing wide end portions. The webbed side wall defines an inboard curved edge 56 and an outboard curved edge 58 . A main body portion 60 extends towards the outboard side from the outboard curved edge of the webbed side wall. The main body portion generally conforms with the transition portion of the mounting flange portion. The air scoop of FIG. 5 may be installed on a brake drum such as in FIGS. 3 and 4 via welding or similar mode of attachment such as known in the art. It will be also appreciated that the air scoop of FIG. 5 and as shown installed in FIGS. 3 and 4 is designed to operate on a brake drum regardless of whether the brake drum is mounted to the left side or the right side of a vehicle. In particular, the air scoop of FIG. 5 defines opposing louver openings 62 separated by a deflector surface 64 which is defined by a mid-portion 66 of the lower surface 68 of the curved or concave back wall.
[0034] FIG. 6 is a partial side view of a brake drum which is adapted for installation at the front of a vehicle. The brake drum of FIG. 6 includes the air scoop 34 of FIG. 5 .
[0035] FIG. 7 relates to a second embodiment of the present invention. A partial view of a brake drum is shown and which is adapted for installation at the front of a vehicle. The brake drum includes the cylindrical portion and the mounting flange portion having the transition portion. The transition portion includes a plurality of vent openings (not shown in FIG. 7 ) such as disclosed in the previous figures. FIG. 7 differs from that of FIG. 6 as to the embodiment of the air scoop 70 to which is shown secured to the transition portion and the cylindrical portion, such as via welding or other similar attachment means known in the art.
[0036] FIG. 8 shows a perspective view of the air scoop 70 of FIG. 7 . The air scoop of FIG. 8 includes a flat inboard side wall 72 having an upper curved or convex edge 74 , a lower edge 76 and two substantially flat side edges 78 . A curved or convex back wall 80 is shown to include an inboard longitudinal edge 82 from which the back wall extends at a right angle from the inboard side wall. The back wall includes an outboard curved edge 84 from which an angled side wall 86 extends radially and towards the outboard side. The angled outboard side wall includes side edges 88 and a distal edge 90 . A planar mounting flange 92 extends from the distal edge and generally conforms to the transition portion of the mounting flange. A deflective surface or webbed wall 94 extends generally from the flat inboard side wall, along the underside of the back wall, and to the underside of the side wall. It will be appreciated that the deflector surface or webbed wall may be substantially planar or may also be designed wherein the webbed wall extends radially outward and in a diverging manner forming a curved deflector surface on opposing sides of the louver openings 96 . The air scoop of FIG. 8 maybe secure to the two-piece composite brake drum of FIG. 7 such as via welding or similar attachment means.
[0037] FIG. 9 discloses a third embodiment of the present invention. In particular, a partial view of the mounting flange portion of a brake drum is shown. The mounting flange portion is adapted for installation at the front of a vehicle. The mounting flange portion includes the transition portion having a plurality of vent openings (not shown) in a manner similar to that shown in the previous figures. An air scoop 100 is shown secured to the transition portion over a vent opening in accordance to the present invention.
[0038] The air scoop 100 of FIG. 9 is shown in the perspective view in FIG. 10 . The air scoop includes a generally planar main body portion 102 having a curved portion 104 . The planar main body portion and curved portion generally conform to the transition portion of the mounting flange portion as shown in FIG. 9 . The main body portion includes two side edges 106 and an outboard edge 108 . An opening 110 extends through the main body portion. A clip 112 extends from each of the side edges. Each clip includes a main flange portion 114 extending radially inward, and a lip portion 116 . A louver 118 is located over the opening 110 and defines a louver opening 120 . The louver includes an inboard wall 122 which is substantially at a right angle to the main body portion 102 , an upper wall 124 which is substantially parallel to the main body portion 102 , an outboard wall 126 which is inclined at approximately a 45° angle to the main body portion 102 . The walls 122 , 124 , 126 taper downwardly away from the louver opening 120 to a back side 128 of the louver at the main body portion. The air scoop of FIG. 10 maybe installed in a brake drum via a snap fitted installation technique, wherein the clips extend through the vent opening into the brake drum cavity and the lip portion retains the scoop in position. Further, it will be appreciated that if the curved portion of the planar main body is omitted, the air scoop of FIG. 10 could be installed on a brake drum regardless of which side of the vehicle the brake drum is to be installed.
[0039] FIG. 11 discloses a fourth embodiment of the present invention. In particular, FIG. 11 discloses a partial perspective view of a mounting flange of a brake drum. A mounting flange includes the transition portion having a plurality of vent openings (of which only one is shown). An air scoop 130 is shown at the vent opening.
[0040] FIG. 12 is a partial side view of the mounting flange of FIG. 11 . The air scoop 130 is shown to include a back wall 132 extending from an inboard portion of the transition portion toward the outboard side. The air scoop is further shown to include a side wall 134 extending from the back wall and radially outwardly toward the outboard side toward the transition portion. The air scoop forms dual opposing louver openings 136 . The air scoop of FIGS. 11 and 12 maybe formed during a stamping and cutting process as an integral unit, or maybe a separate component which is individually secured to the mounting flange such as via welding.
[0041] It will be appreciated that a brake drum having a plurality of air scoops in accordance with the present invention maybe installed on the vehicle. The air scoops will be typically secured to the transition portion and/or cylindrical main body portion, and may be located within the air gap defined between the brake drum and wheel. Rotation of the wheel and brake drum combination will induce air flow into louver opening and into the brake drum cavity providing ventilation. Ventilation will aid in cooling, cleaning and the removing of debris. It will be further appreciated that the air scoops will have a tendency to prevent water from entering the brake drum such as during washing of the vehicle and wheels.
[0042] The present invention is applicable to a steel shell brake drum, a two-piece brake drum, a composite brake drum, a cast brake drum, and other embodiments, as will be appreciated. | One embodiment of a brake drum includes a cylindrical main body portion, a brake drum mounting flange portion, a brake drum transition portion, the brake drum transition portion extending between the cylindrical main body portion and the mounting flange portion, the transition portion having a plurality of vent openings, and one air scoop secured at each of the vent openings, whereby rotation of the brake drum and air scoop induces air movement within a brake drum cavity defined by the main body portion. Each air scoop defines a louver opening which faces the angular direction of drum rotation, an air channel in fluid communication with the louver opening and the brake drum cavity, and a deflection surface located in the air channel. The deflection surface is positioned to re-direct air movement entering the louver opening at an angular direction, to a generally radial and inboard direction | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to clips used to releasably attach a retractable (sometimes also referred to as coilable or recoilable) tape measure to a user's clothing, and more particularly to clips for retractable tape measures having structural provision for selectively receiving a writing instrument, as for example a pencil.
2. Description of the Prior Art
Retractable tape measures have become an indispensable tool of tradespeople because of their inherent compactness, ease of use and accuracy of the provided measurement. Retractable tape measures include a case; a flexible, elongated blade upon which distance measurements are printed; a hook end typically having a special slot therein which allows a nail to serve as a pivot for drawing circles measured therefrom; a spring rewinding mechanism for retracting the blade via biased spooling thereof; a release button for selectively actuating the rewinding mechanism when the blade is extended; and a clip connected to a side of the case for clipping the case onto an article of clothing of the user, such as for example a belt.
One of the most frequent uses of a retractable tape measure is to measure a distance across an object, such as a board or sheet of building material, in preparation for its being cut or otherwise acted upon. In order for the user to remember the exact location of the measured spot, it is necessary to leave a mark on the surface of the object at the spot, usually via a writing instrument such as a pencil, pen, marker or crayon. However, since it is so easy to have accidentally placed a writing instrument out of reach when the measurement is taken, the measurement has to be repeated with the writing instrument in hand.
Further, as alluded to hereinabove, retractable tape measures may be used to draw circles on the surface of an object whereby a nail head forms the radial center, the special slot of the hook end of the blade engages the nail head, and the blade serves as a radius of various lengths. In order to provide a circle mark as accurate as possible, the user must try to hold the case and a writing instrument against the case as the case is arcingly moved about the nail head center pivot. Frequently, the actual result is not only radially inaccurate, but also the circumference is drawn unsteady (ie., wavy, somewhat sawtooth-locking) rather than drawn smoothly, especially if the surface grain is rough.
Accordingly, it would be most beneficial if somehow a writing instrument could be removably attached to a retractable tape measure so that the writing instrument is always present to mark the spot whenever a measurement is made, and further so that the writing instrument is located relative to the case so that accurate arcs can be drawn with respect to a nail head centerpoint.
SUMMARY OF THE INVENTION
The present invention is a clip for a retractable tape measure which is structured to seatably receive a writing instrument so that the writing instrument is always present to mark the spot whenever a measurement is to be made, and further so that the writing instrument is located relative to the case so that accurate arcs can be drawn with respect to a nail head (or other analogous protruding structure).
The clip according to the present invention includes a clip body composed of a base member for being anchored fastenably to the case of a retractable tape measure and a spring member integrally connected with the base member for resiliently yielding when an article is slipped between the base and spring members. The clip further includes a writing instrument holder associated with the clip body for removably receiving a writing instrument. The preferred clip is constructed of high yield spring type stainless steel sheet material, wherein the clip body and the writing instrument holder are integrally formed in a single piece.
In a first preferred embodiment of the clip according to the present invention, the clip body includes a base member shaped to seat (form fit) into a recess formed in the exterior of the rear side of the case of the retractable tape measure. The base member has an affixing hole for a threaded fastener to connect it to the case. The spring member is formed of an inboard portion of the clip body which is looped via an arcuate bend so as to generally adjacently overlap, and be resiliently biased toward, the base member. The writing instrument holder is formed of outboard portions (one on either side of the inboard portion) of the clip body which are bent into arcuate fingers adjacent the arcuate bend. It is preferred for the clip to be orientable in either of two perpendicular directions relative to the case.
In a second preferred embodiment of the clip according to the present invention, the clip body includes a base member shaped to seat (form fit) into a recess formed in the exterior of the rear side of the case of the retractable tape measure. The base member has an affixing hole for a threaded fastener to connect it to the case. The spring member is formed of the clip body by its being looped via an arcuate bend so as to generally adjacently overlap, and be resiliently biased toward, the base member. The writing instrument holder is formed of the spring member having a medial aperture and a centrally located slot in the arcuate bend that connects with the medial aperture. A writing instrument is disposed adjoining the base member by being placed into the slot and medial aperture and between the base member and the spring member at its distal end.
In a third embodiment of a clip according to the present invention, the writing instrument holders of the first and second preferred embodiments are included.
In a fourth embodiment of the clip according to the present invention, a conventional clip for a retractable tape measure is utilized in conjunction with a writing instrument holder which is connected with the case, wherein the writing instrument holder is in the form of arcuate fingers adjacent the arcuate bend of the clip.
In operation, the clip according to the present invention serves as an article clipping device in a conventional manner, wherein an article of the user's clothing is resiliently held between the spring and base members so as to selectively attach the case of the retractable tape measure to the clothing of the user. Further, the clip according to the present invention selectively holds a writing instrument which has been thrust axially into the writing instrument holder. In the event an arc is to be drawn with respect to a nail head via the hook end of the retractable tape measure, the writing instrument holder securely holds the writing instrument with respect to the case so that the resulting drawn circumference is both accurate and smooth. The advantage of the first, third and fourth preferred embodiments of the clip according to the present invention is that the spring member and the writing instrument holder are able to operate independently, so that a writing instrument may be received while the clip is simultaneously engaged with an article of clothing.
Accordingly, it is an object of the present invention to provide a clip which has provision for releasably holding a writing instrument.
It is an additional object of the present invention to provide a clip for a retractable tape measure, wherein the clip functions to attach the retractable tape measure to an article of clothing of the user and further functions simultaneously to releasably retain a writing instrument.
It is another object of the present invention to provide a clip for a retractable tape measure which provides location for a writing instrument with respect to the case of the retractable tape measure when the retractable tape measure is being used to draw a circumference.
It is a further object of the present invention to provide retractable tape measure, wherein the clip thereof is positionable in selected orientations, preferably in mutually perpendicular orientations.
It is yet a further object of the present invention to provide a writing instrument holder for retrofitting with a conventional clip of a retractable tape measure or another object.
These, and additional objects, advantages, features and benefits of the present invention will become apparent from the following specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a clip according to a first embodiment of the present invention, shown in operation with respect to a writing instrument and at a first orientation with respect to a retractable tape measure.
FIG. 2 is a rear side view of a retractable tape measure equipped with the clip according to the first embodiment of the present invention, wherein the clip is shown at the first orientation, and shown in phantom at a second, perpendicular, orientation.
FIG. 3 is a top, partly broken-away, partly sectional view of the retractable tape measure equipped with the clip according to the first embodiment of the present invention.
FIG. 4 is a front side view of a retractable tape measure shown in operation wherein the clip is holding a writing instrument and is clipped onto a user's belt, where the clip according to the first embodiment of the present invention is in the first orientation.
FIG. 5 is a front side view of a retractable tape measure shown in operation where the clip is holding a writing instrument and is clipped onto a user's belt, where the clip according to the first embodiment of the present invention is in the second orientation.
FIG. 6 is a perspective view of a retractable tape measure showing the rear side thereof having a bidirectional recess for seating a clip according to the present invention in two mutually perpendicular orientations.
FIG. 7 is a rear side view of a retractable tape measure equipped with a clip according to a second embodiment of the present invention, wherein the clip is shown in operation holding a writing instrument during the drawing of an arc.
FIG. 8 is a top plan view of a retractable tape measure equipped with the clip according to the second embodiment of the present invention, shown in operation holding a writing instrument,
FIG. 9 is a perspective view of a clip according to a third preferred embodiment of the present invention, shown in operation with respect to writing instruments (shown in phantom).
FIG. 10 is an exploded perspective view of a retractable tape measure, conventional clip therefor and writing instrument holder according to a fourth embodiment of the present invention.
FIG. 11 is a side view of a writing instrument holder according to the present invention equipped with a writing instrument point protector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the Drawing, a clip 10 according to a first embodiment of the present invention is shown by FIGS. 1 through 6. The clip 10 is attached to the rear side 12a of the case 12 of a retractable tape measure 14 via, for example, a threaded fastener 16. The clip 10 serves to clippingly hold the retractable tape measure 14 to an article of the user's clothing, such as for example a belt, and further serves to releasably hold a writing instrument, such as for example a pen, pencil, crayon or marker, proximate the case 12.
The clip 10 includes a clip body 18 having a base member 20 and a spring member 22, preferably formed of a single piece of sheet stock, where the sheet stock is preferred to be a spring type stainless steel. The base member 20 is structured to be affixed to the rear side 12a of the case 12. The spring member 22 is formed by an arcuate bend 30 formed in an inboard portion 18a of the clip body 18 commencing at the base member 20, wherein the spring member is looped back so as to be resiliently biased against the base member. The spring member 22 is preferred to have an outwardly curved distal end 22a for facilitating slipping an article, such as a user's belt, between the spring member and the base member. In this regard, the clip body 18 serves to clippingly attach the case 12 to an article of clothing of the user, such as a belt, via resilient biasing vis-a-vis the base and spring members 20, 22 when the article is slid therebetween. The base member includes an affixing hole 20a through which the threaded fastener 16 extends and then threadably fastens to the case 12.
The clip 10 further includes a writing instrument holder 24 integrally connected with the clip body 18. The writing instrument holder 24 is formed by an outboard portion 18b of the clip body 18 being curvably bent to thereby form two spaced apart arcuate fingers 26a, 26b located adjacent the arcuate bend 30 of the clip body 18. It is to be understood that while the writing instrument holder 24 is preferred to be integrally connected with the clip body 18, this is not a requirement. The convex surface of the arcuate bend 30, the concave surface of each of the arcuate fingers 26a, 26b and the immediately adjacent surface of the rear side 12a of the case 12 collectively form a receptacle 32 (as best shown by FIG. 3) for receiving a writing instrument 28 by the writing instrument being axially slid thereinto. With respect to facilitating sliding of the writing instrument 28 into the receptacle 32, a bevel 34 is provided at each end of the arcuate bend 30 (see FIGS. 2 and 3). Thus, as a user begins to insert the writing instrument axially into the receptacle 32, the bevels 34 guide entry of the writing instrument 28 and further serve to save the surface of the writing instrument from being scarred, as would otherwise occur as the writing instrument scraped against an end of the arcuate bend 30.
The rear side 12a of the case 12 is preferably provided with a recess into which the base member 20 of the clip body 18 seats. As depicted by FIG. 6, it is preferred for the recess 36 to have a bidirectional pattern, whereby the base member 20 is seatable selectably in either of two mutually perpendicular orientations relative to the case 12, as shown in FIGS. 4 and 5. That is, when the base member 20 seats in a first portion 36a of the recess 36, the clip 10 is oriented at a first orientation relative to the case 12 as shown in FIG. 4; and when the base member seats in a second portion 36b of the recess, the clip is oriented at a second orientation relative to the case as shown in FIG. 5. An advantage of the base member 20 being seated in the first portion 36a of the recess 36, whereby the clip 10 is oriented in the first orientation as shown in FIG. 1, is that the writing instrument 28 is in ready position to draw a circumference line 46.
In operation, a user uses the clip body 18 to clippably attach the case 12 to an article of the user's clothing in a conventional manner. The user slips, axially, a writing instrument 28 into the receptacle 32 formed between the arcuate fingers 26a, 26b, the arcuate bend 30 and the surface 12a of the case 12 to thereby hold the writing instrument to the casing 12. In this regard, FIG. 1 depicts an example of operation wherein the special slot 38a of the hook end 38 of the blade 40 of the retractable tape measure 14 engaged with a nail head 42, wherein a circle circumference is desired to be drawn on the surface 44a of an object 44. The writing instrument 28 is located fixedly with respect to the case 12 so that as the user moves the case arcingly about the nail head 42, the writing instrument provides a smooth and accurately radiused circumferential line 46.
Referring now additionally to FIGS. 7 and 8, a second preferred embodiment of the clip 10' will be detailed.
The writing instrument 28 and the retractable measuring tape 14', including the case 12' and rear side 12a', are as above recounted, with the exception that the recess 36' is conventionally configured, where the recess is shaped analogous to that of the second portion 36b of the recess 36 shown in FIG. 6.
The clip 10' includes a clip body 18' having a base member 20' and a spring member 22', preferably, as in the case of the clip body 18, formed of a single piece of sheet stock, wherein the sheet stock is preferred to be a spring type stainless steel. The spring member 22' is formed by an arcuate bend 30' formed of the clip body 18' commencing at the base member 20', where the spring member is looped back so as to be resiliently biased against the base member. A medial aperture 48 of general shape is provided in the spring member 22' and a slot 50 is provided in a central section of the arcuate bend 30' which extends into the medial aperture.
The spring member 22' is preferred to have an outwardly curved distal end 22a' for facilitating slipping an article between the base and spring members, as described hereinabove relative to the first embodiment of the clip 10. The base member 20' seats into the recess 36', and is connected with the rear surface 12a' of the case 12' in the manner described hereinabove.
The writing instrument holder 24' of the clip 10' includes the aforementioned slot 50 and medial aperture 48, and preferably includes a shallow bend 52 formed in the distal end 22a' of the spring member 22' at the medial aperture and directly in line with the slot. In this regard, the writing instrument 28 is slid axially through the slot 50, through the medial aperture 48 and then between the base member 20' and the distal end 22a' of the spring member 22 at the shallow bend 52, wherein the shallow bend receives the writing instrument and the sides of the slot and the shallow bend serve to guide the orientation of the writing instrument with respect to the case, and wherein the biasing of the spring member against the writing instrument serves to squeeze it fixedly, yet releasably, in place relative to the clip 10'.
FIG. 7 depicts an example of operation wherein the hook end 38 of the blade 40 of the retractable tape measure 14' engaged with a nail head 42, wherein a circumferential line 46 is desired to be drawn on the surface 44a of an object 44. The writing instrument 28 is located fixedly with respect to the case 12' via the writing instrument holder 24' so that as the user moves the case arcingly about the nail head 42, the writing instrument provides a smooth and accurately radiused circumferential line 46.
Referring now additionally to FIG. 9, a third preferred embodiment of the clip 10" will be detailed, wherein first and second writing instrument holders 54, 56 are provided.
The writing instrument 28 and the retractable measuring tape 14', including the case 12' and rear side 12a', are as above recounted, with the exception that the recess 36" is, by way of exemplification, similar to that shown by FIG. 7 for seatably receiving a similarly shaped base member.
The clip 10" includes a clip body 18" having a base member 20" and a spring member 22", preferably, as in the case of the clip body 18, formed of a single piece of sheet stock, preferably spring type stainless steel The spring member 22" is formed by an arcuate bend 30" formed of the clip body 18" commencing at the base member 20", wherein the spring member is looped back so as to be resiliently biased against the base member. A medial aperture 48' of general shape is provided in the spring member 22" and a slot 50' is provided in a central section of the arcuate bend 30" which extends into the medial aperture.
The spring member 22" is preferred to have an outwardly curved distal end 22a" for facilitating slipping an article between the base and spring members, as described hereinabove relative to the first embodiment of the clip 10. The base member 20" seats into the recess 36" and is thereupon connected with the rear surface 12a' of the case 12' in the manner described hereinabove.
The first writing instrument holder 54 of the clip 10" is similar to that of the writing instrument holder 24' of the second preferred embodiment of the clip 10', and includes the slot 50' and medial aperture 48', and preferably includes a shallow bend 52' formed in the distal end 22a" of the spring member 22" at the medial aperture and directly in line with the slot. In operation of the first writing instrument holder 54, the writing instrument 28 is slid axially through the slot 50', through the medial aperture 48' and then between the base member 20" and the distal end 22a" of the spring member 22' at the shallow bend 52', wherein the sides of the slot and the shallow bend serve to guide the orientation of the writing instrument with respect to the case, and the biasing of the spring member against the writing instrument squeezably holds it fixedly, yet releasably, in place relative to the clip 10'.
The second writing instrument holder 56 of the clip 10" is somewhat similar to that of the writing instrument holder 24 of the first preferred embodiment of the clip 10, and is integrally connected with the clip body 18". The second writing instrument holder 56 is formed by an outboard portion 18b' of the clip body 18" being curvably bent to thereby form two spaced apart arcuate fingers 26a', 26b' located adjacent the arcuate bend 30' of the clip body 18, wherein the bend direction is opposite that shown in FIG. 3. A groove 58 is formed in the convex surface of the arcuate bend 30". The surface of the arcuate bend 30" at the groove 58 and the concave surface of the first and second arcuate fingers 26a', 26b' form a receptacle 32' for receiving a writing instrument 28. A bevel 34' may be optionally provided at each end of the arcuate bend 30". In operation of the second writing instrument holder 56, a writing instrument 28 is axially slid concentrically with respect to each of the first and second arcuate fingers 26a', 26b' and the groove 58 to thereby become received in the receptacle 32'.
Referring now additionally to FIG. 10, a fourth preferred embodiment of the clip will be detailed, wherein a writing instrument holder 60 is provided for operation with respect to a conventional clip 62.
The retractable tape measure 14' is conventional and the clip 62 associated therewith is conventional The writing instrument holder 60 is formed of a single piece of sheet stock, such as stainless steel The writing instrument holder 60 includes a base 64 having an affixing hole 66 for being engaged by a threaded fastener 16. In this regard, the user removes the threaded fastener 16, places the base 64 between the base member 62a of the conventional clip 62 and the rear side 12a' of the case 12', and then re-threads the threaded fastener with respect to the case.
The writing instrument holder 60 further includes one or more, preferably two, as shown, arcuate fingers 68. The arcuate fingers 68 are spaced relative to the arcuate bend 62b of the conventional clip 62 generally similar to that depicted in FIG. 9, so that a writing instrument is axially insertable into the receptacle formed between the concave surface of the arcuate fingers and the convex surface of the arcuate bend, whereby the writing instrument is inserted thereto as recounted with respect to FIG. 9 (sans the groove). In this manner, a conventional retractable tape measure is easily converted to having a writing instrument holder without need for replacing or modifying any parts thereof. The writing instrument holder 60 may be attached to other articles via a suitable threaded fastener.
It should be noted that while the writing instrument holder 60 is shown in FIG. 10 in a conventional orientation, it may be rotated 90 degrees to thereby orient the writing instrument carried by it so that the writing instrument may be used to draw a circumferential line with the retractable tape measure.
FIG. 11 depots a modification of a writing instrument holder 70 according to the present invention, wherein one end thereof is provided with a point protector 72. Preferably, the point protector 72 is generally conical in shape and is interiorly dimensioned to receive the pointed end of a writing instrument, such as a pencil, so as to protect to point from damage, as well as prevent the point from accidentally in,ring the user when the writing instrument is held by the writing instrument holder 70. It should be noted that the examples of writing instrument holders of FIGS. 1 through 6, the second writing instrument holder of FIG. 9, and FIG. 10 may be provided with the point protector.
It should be noted that the arcuate fingers disclosed herein may operate to hold a writing instrument with or without the assistance of the arcuate bend of the clip.
To those skilled in the art to which this invention appertains, the above described preferred embodiment may be subject to change or modification. For example, while the preferred article for being connected with the writing instrument holding clip according to the present invention is a retractable tape measure, other articles may be so connected, such as for example a pager, cellular telephone or calculator. Such change or modification can be carried out without departing from the scope of the invention, which is intended to be limited only by the scope of the appended claims. | A clip for a retractable tape measure which is structured to seatably receive a writing instrument so that the writing instrument is always present to mark the spot whenever a measurement is made, and further so that the writing instrument is located relative to the case so that accurate arcs can be drawn with respect to a nail head centerpoint. The clip includes a clip body composed of a base member for being connected to the case of a retractable tape measure, a spring member integrally connected with the base member for resiliently yielding when an article is slipped between the base and spring members. The clip further includes a writing instrument holder adjacent with the base member for removably receiving a writing instrument. The preferred clip is constructed of stainless steel sheet stock, preferably a spring type stainless steel material, wherein the clip body and the writing instrument holder are integrally formed in a single piece. A point protector for received writing instruments may be optionally included. | 6 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to an improved method for determining the pressure of fluid contained in a sedimentary rock. A mineralogically general force balanced stress/strain--loading limb relationship is a starting point. This relationship is defined in U.S. Pat. No. 5,282,384 to Holbrook, assigned to the assignee of the present invention, and which is incorporated herein by reference, which discloses how to calculate sedimentary rock pore pressure when the effective stress load is either constant or increasing and also teaches how the minimum principal stress and fracture pressure also can be calculated from in situ strain data in Normal Fault Regime ˜biaxial basins. Fracture pressure and pore fluid pressure are the safe force balance borehole fluid pressure limits for drilling the uncased (open to the surface) portion of a borehole into the subsurface.
Well after these loading limb open borehole force balance relationships were disclosed in the prior Holbrook patent, an extended set of force balanced Earth in situ stress/strain inter-relationships was discovered. These Earth in situ force balance inter-relationships can be applied to further improve the drilling decision making process. This newly discovered Earth in situ force balance inter-relationship, led to a direct force balance means of determining the physical location and pressure upper limit of fluid expansion generated pore fluid pressure. The methods disclosed in this invention produce further valuable geological information from in situ petrophysical measurements which is useful in the hydrocarbon recovery industry.
2. Background
Pore fluid pressure and fracture pressure are the most important external geologic factors affecting the safety and cost of drilling of an oil well. Exceeding either in situ force balance limit in an open borehole frequently leads to dangerous and usually costly well control problems. The borehole fluid hydrostatic pressure (Pb) must be greater than the formation pore fluid pressure (P p ) if one is to avoid the risk of a possibly catastrophic blowout. Likewise, the borehole fluid circulating pressure must be less than the fracture propagation pressure (Pf) if one is to avoid the risk of lost circulation.
Several expensive casing strings are usually required so that an oil well can be drilled within the limits of the open borehole pore fluid pressure and fracture propagation pressure limits. Great savings would be realized during well planning if one or more casing string could be eliminated through better pore pressure and fracture pressure knowledge. The present invention also enhances the safety of oil or gas well drilling operations. Presently, a considerable portion of expensive rig time is spent in a remedial fashion dealing with unexpected pore pressure and fracture pressure problems encountered while drilling. The improved information from this invention should significantly reduce drilling operations costs by reducing the number of these dangerous situations.
Because of the critical relationship to drilling operations, there are numerous techniques for calculating pore fluid pressure. All known petrophysical prior art methods calculate pore fluid pressure indirectly based upon measured rock properties. Most of these methods follow a calibration procedure which is not based on mechanical or physical information. Instead, these calibration procedures are generally based upon the extension of an observed empirical relationship between a measured physical parameter and a "normal" or hydrostatic compaction trend. The empirical "normal" trend line (Pn) is the average value of the measured parameter which changes as a function of depth.
The change in the measured parameter (Pn) as a function of depth according to these prior art techniques is indirectly related to a change in compaction of the sedimentary rock. The measured parameter described in a pressure prediction technique is usually not compactional strain. The method operator in charge of pore pressure prediction must then decide whether the extrapolated "normal" compaction vs. depth trend line being used is correct or not using some non-physical interpretive basis. Direct empirical (i.e. non-physical) relationships have been the only pore pressure prediction techniques used by the oil industry until very recently.
Sedimentary rocks are compacted by the effective stress applied to their grain matrix framework. When fluid pressure is approximately hydrostatic and the overburden is gradually increasing, both depth and effective stress are increasing. Under these conditions, depth behaves as a pseudo-stress variable. However, when pore pressure is elevated, effective stress and overburden gradients can be either increasing or decreasing and depth is not a pseudo-stress variable.
Most of the prior art methods for determining pore fluid pressure use depth as a pseudo-stress variable in both "normal" and "excess" pressured intervals which results in significant pore pressure calculation errors. The potential for this error when using a non-physical velocity-depth trend line method will be illustrated later in reference to the patents to Kan et al.
Another significant failing of most prior art pore pressure calculation techniques is attributable to their basic formulation. According to prior art depth trend techniques, pore pressure (P p ) is calculated as a sum of "normal" hydrostatic fluid pressure which is inferred from an extended compaction-depth trend; plus a differential or "excess" fluid pressure (ΔP) which is related to a measured difference from the "normal" trend. The (ΔP) calibration or correction term is back calculated after the fact from measured pore pressures in a nearby well or group of wells within a local area. The equation expressing this non-physical local calibration relationship is:
Pp=Pn+ΔP (1)
where Pp is the pressure of fluid in the pore space of rock, Pn is the empirical calculation of the normal pressure trend line and ΔP is the difference in pressure from the normal pressure trend line.
Equation (1) is not a physically representative mathematical formulation. Pascal's Principle requires that all of the fluids in a given local pore space or container be at the same pressure. Physically speaking, "excess" pressure cannot and does not exist in a pore space. Since the "excess" pressure term (ΔP) does not exist in nature, "excess" pressure cannot be physically related to any measured parameter. Calibrating a measured physical parameter to a quantity which does not exist, i.e. (ΔP), has been an acceptable engineering shortcut for a long time. The penalty when applying this (Pp=Pn+ΔP) shortcut method is that the results are specific to the calibration area and the fluid pressurization mechanism in that particular field or reservoir. "Normal compaction trend" operators usually do not know the fluid pressurization mechanism, nor can they change their procedure to account for the mechanism. The (ΔP) calibration is fundamentally non-physical and not related to the known loading and unloading stress/strain relationships of sedimentary rocks. As these stress/strain relationships are so different, there is great risk in mis-applying an empirical (Pp=Pn+ΔP) relationship which contain no means of determining stress paths.
U.S. Pat. No. 5,081,612 to Scott et al discloses a method for determining formation pore pressure from remotely sensed seismic data. This particular method depends upon a hydrostatically compacted reference velocity vs. depth (Pn) profile. Referring back to Equation 1, this profile is essentially an observed or inferred curved (Pn) velocity gradient. The Scott et al pore pressure gradient technique applies to shale, which is also common to most of the prior art methods using a (Pp=Pn+ΔP) formulation. Pore pressures are calculated with respect to the reference velocity vs. depth trend line which is an indirect violation of Pascal's Principle.
In U.S. Pat. Nos. 5,130,949 and 5,233,568 to Kan et al, like U.S. Pat. No. 5,081,612 to Scott et al, the basic pore pressure prediction method is also based upon a velocity vs. depth compaction trend line. Kan et al's FIG. 5 demonstrates the historically common but physically incorrect (Pp=Pn+ΔP) methodology. The normal compaction trend line interpreted from the hydrostatic zone is shown on FIGS. 5b and 5d. The lowest hydrostatically compacted data point is slightly above 5,000 feet. The extrapolated (Pn) interval transit time-depth trend line decreases by half continuously every 8,000 feet on the logarithmic transit time scale shown.
The extrapolated empirical (Pn) shale transit time--depth trend line is beyond any possible physical reality at 8,000 feet or essentially 3,000 feet into the overpressured zone. Shales can compact no further than zero porosity which corresponds to a transit time of about 90 microseconds/foot. In regions that are more nearly hydrostatic than the example shown in reproduced FIG. 5, the 90 microseconds/foot shale transit time limit is not reached at depths above 20,000 feet.
The calibration within the (Pn) hydrostatic zone above 5,000 feet is reasonable. The projection to 90 microseconds/foot 3,000 feet below top of overpressure is physically unreasonable. Quartz is the most compaction resistant sedimentary mineral. The extrapolated (Pn) trend passes the zero porosity quartz transit time of 56 microseconds/foot at about 14,000 feet. The transit time of the Mohorovic discontinuity below the base of the Earth's crust is about 37 microseconds/foot. The (Pn) trend line is 37 microseconds/foot at 19,000 feet and continues to increase below. The actual depth of the base of the crust is about 100,000 feet on average, not 19,000 feet which is extrapolated from the interpreted normal shale compaction (Pn) depth trend of FIG. 5 of Kan et al.
The extrapolated (Pn) trend is grossly off compared to known transit time limits below the hydrostatic zone. Applying the (Pp=Pn+ΔP) methodology the known error in the projected (Pn) depth trend is forced into the (ΔP) term which is calculated by difference. Thus, the physically unreasonable (Pn) trend is automatically compensated for by the physically invalid (Pn+ΔP) formulation relied upon for calibration. In fact any combination of (Pn+ΔP) is forced to the correct answer by the measured pore pressure (Pp) in a calibration well. It takes two equal and opposite wrongs; one physically unrealistic (Pn), and one physically invalid (ΔP) to make a right (Pp). Whenever the extrapolated (Pp=Pn+ΔP) trend line methodology is reported to have been successfully applied; it signifies only that a force balance (ΔP) correction has been applied to a frequently erroneous extrapolated (Pn) trend line.
All of the extrapolated (Pp=Pn+ΔP) trend line methods suffer from the same non-physical (Pn) extrapolation which is transparent to the operator after the local calibration is made. The calibrations have only local applicability because you get a different extrapolated (Pn) trend depending upon where the base of the hydrostatically compacted depth interval occurs. In any particular area many other physical factors, for example overburden gradient, that exist affect the empirical calibration at that depth but are not accounted for in the empirical short cut methodology.
There are at least three (3) prior art methods for determining pore fluid pressure from petrophysical measurements which are based upon the effective stress law. A one-dimensional gravitational force balance was elucidated by Terzaghi, in his 1941 article entitled "Undisturbed Clay Samples and Undisturbed Clays", discussing compaction studies of marine sediments. Terzaghi first presented this uniaxial force balance equation;
Pp=S.sub.v -σ.sub.v ( 2)
This relationship states that the fluid pressure in the pore space (Pp) can be calculated as the difference between the overburden load (Sv) and the vertical load borne by the sediment grain--grain contacts (σ v ). In the science of rock and soil mechanics, this (σ v ) term is known as the effective vertical stress.
U.S. Pat. No. 5,200,929 to Bowers is based upon in situ empirically determined velocity vs. calculated effective stress relationships. It uses the Terzaghi uniaxial Equation (2) to calculate effective stress. In NFR˜biaxial basins the uniaxial calibration is coincidentally related to average effective stress force balance which directly causes the observed sediment compaction. This method accounts for both the loading and unloading stress/strain relationships of sedimentary rocks. The method is intended for use only in velocity reversal zones where fluid expansion unloading is the known fluid pressurization mechanism. The method is dependent only on velocity measurements which are indirectly related to strain and lithology.
The Bowers method is a significant technical advance because it uses a uniaxial approximate measure of effective stress and for its recognition of stress/strain hysteresis in sedimentary rocks. However, like the previously described pore pressure methods, the Bowers method also depends upon local empirical-velocity calibration to determine the coefficients for all its calibration and pore pressure prediction relationships.
Using in situ velocity vs. effective stress data for shales only, Bowers describes a method for defining the shape of loading and unloading effective stress-shale acoustic velocity curves. His "virgin curve relationship" is portrayed as the solid line on Bower's FIG. 4. This curve corresponds to a loading limb stress/strain relationship with shale velocity being the indirect measure of strain.
At present the shale velocity-strain relationship is still poorly known. The velocity of an individual shale sample varies by up to 25% depending on whether the measurement is made parallel or perpendicular to bedding, as discussed in a 1994 article by Sayers, entitled "The Elastic Anisotropy of Shales". An in situ measurement of velocity on shales with identical strain would produce very different pore pressure answers depending on the formation dip at the measurement location.
FIG. 4 of the Bowers patent shows how the extension of local empirical velocity loading limb and unloading limb relationships intersect. The position of this intersection point in both depth and effective stress space has a major impact on the value of the unloading limb calculated pore pressure. The data from both loading and unloading limbs must be known and their curving functions determined through interpolation before their intersection point can be determined by extrapolation. No other means for establishing the onset of unloading limb pore pressure is revealed by Bowers. If this method were to be applied with real-time Measurement-While-Drilling data, one would not have a criterion to determine where and when to switch from loading to unloading stress-velocity relationships.
U K Patent No. 2,174,201A to Fitzgerald reveals a common misunderstanding with respect to the interpretation of laboratory vs. in situ stress/strain relationships. Fitzgerald's method is based upon two (2) linear acoustic velocity vs. stress relationships observed in two (2) shales in a laboratory. Virtually all observed laboratory stress/strain relationships occur along the dominantly elastic unloading-reloading stress path of a rock sample. These rock specific stress paths intersect a mineralogy specific loading limb stress path at the point of maximum effective stress loading. There is no clear indication apparent during laboratory experiments on relatively hard rocks when or where the hysteresis join point is reached. The slopes of the initial loading vs. unloading-reloading limbs are very different.
Fitzgerald's patent indicates a lack of awareness of stress/strain hysteresis in sedimentary rocks and makes calculations based only upon the unloading-reloading stress path. In Fitzgerald, the key rock description qualifier "known constitution" is entirely appropriate and correct. For this method to operate as described a huge catalog of "known constituent" sedimentary rocks would have to be provided to appropriately match stress paths. Only two (2) rock stress paths are described. Fitzgerald describes three (3) empirical stress path coefficients which would need to be established to have a predictive equation. These coefficients could not be established without the "known constituent" rock sample or its equivalent from a rock sample catalog. The Fitzgerald patent is operative only for the two (2) rocks described and could not be generalized into a general subsurface pore pressure predictive method.
U.S. Pat. No. 5,282,384 to Holbrook applies force balance for pore pressure prediction using a power law effective stress/strain compaction function. The key scientific elements to this methodology and approach are:
1. The use of the uniaxial Terzaghi force balance (Equation 2) in ˜biaxial Normal Fault Regime Basins.
2. The correlation of effective stress to solidity (1.0-φ, where φ is porosity) which is a direct measure of in situ strain for granular solids. One skilled in the art will recognize the substitution of the relationship (φ/1.0-φ).
3. The discovery through this application that both vertical effective stress and the effective horizontal/vertical stress ratio in ˜biaxial Normal Fault Regime basins are directly related to in situ strain in all lithologies and at all depths.
These direct stress/strain relationships are related to sedimentary rock mineralogy and expressed quantitatively as Equations 6, 7, and 8 in the Holbrook Pat. No. 5,282,384. These equations and empirical coefficients describe a complete three-dimensional grain and fluid force balance. Additionally, the equations in the patent explain why and how the uniaxial Terzaghi force balance works in ˜biaxial Normal Fault Regime basins where horizontal effective stresses are known to increase with depth. Further, lithologic and stress technical support for the patented method are described in articles by Holbrook in 1995, "The Relationship Between Porosity, Mineralogy, and Effective Stress in Granular Sedimentary Rocks", and 1996, "The Use of Petrophysical Data for Well Planning, Drilling Safety and Efficiency" and "A Simple Closed Force Balanced Solution for Pore Pressure, Overburden, and the Principal Effective Stress in the Earth".
There are severe calibration problems with all of the (Pp=Pn+ΔP) prior art empirical pore pressure prediction methodologies described above. Most of the prior art acoustic pore pressure prediction methodologies use the same non-physical relationship (Equation 1) and suffer the same general pore pressure calibration-prediction problems. The calibrations for all these methods, even including Bowers' (Equation 2) empirical effective stress-velocity relationships apply only locally. The fundamental problem with all the other prior art methods is that of the unspecified relationships between stress and strain. Holbrook (Equation 2) is the only prior art pore pressure method which embodies a direct physical in situ stress/strain calibration basis.
Articles by Ward et al in 1994, "The Application of Petrophysical Data to Improved Pore and Fracture Pressure Determination in North Sea Graben HPHT Wells", and 1995, "Evidence for Sedimentary Unloading caused by Fluid Expansion Overpresssure-generating Mechanics", point out evidence for fluid expansion generated fluid overpressuring which was directly related to in situ measurable strain (solidity). The unloading limb stress/strain (solidity) data plotted in a very different areas are in general agreement with Bowers' "virgin curve" vs. unloading velocity data. Ward et al's FIG. 2 from their 1994 article illustrates the similarities, differences, advantages and implementation problems associated with applying unloading stress/strain relationships to the problem of pore pressure determination.
The Ward et al FIG. 2 loading and unloading limb relationships are power law linear stress/strain functions. The major significant advantages of this over the Bowers calibration are that: 1) effective stress is directly related to in situ strain; and 2) the power law function is linear, not curved, which makes calibration, interpolation and extrapolation much more simple and reliable. FIG. 4 of Bowers and FIG. 2 of Ward et al are geometrically similar. Bowers' shale velocity curves would approximate Ward et al's power law linear stress/strain functions if the appropriate material properties transformations were made. The interpretation calibration step and the pore pressure prediction step are much easier to accomplish and more accurate when using the force balanced power law linear relationships.
Ward et al points out in their FIG. 3 that there are many possible unloading stress/strain relationships related to the loading limb relationship depending on the last peak effective stress loading. The interpretive definition of this loading limb intersection point is a critical problem here as it was in the Bowers' methodology.
Ward et al, in the 1994 article, made some observations which are illustrated as FIGS. 3 and 4 which are coincidentally related to a physical rock properties means of determining the loading vs. fluid expansion unloading intersection point in the subsurface. The depth range of a low porosity vertical seal is shown on the FIG. 3 geologic cross section. Pore fluid pressure gradient as indicated by the heavy curved lines on the figure increases dramatically somewhere within the low porosity seal zone. The onset of fluid expansion unloading probably occurs somewhere in the low porosity seal zone which can be recognized from petrophysical measurements. This relationship is discerned mainly by inference from the markedly different observed pressure gradients above and below the low porosity seal zone. Low porosity is a property of the seal zone, but it does not capture or quantify the actual pressure seal relationship.
Ward et al's 1994 article FIG. 5 is a generalized pressure profile showing the relationships between disequilibrium compaction fluid pressurization mechanisms and fluid expansion pressurization mechanisms. The low porosity vertical seal within the chalk is also shown on this diagram. Supporting this circumstantial evidence are the calculations of which indicated that a very low permeability seal is needed for the fluid expansion pressurization mechanism to be operative.
Gaarenstroom et al, in a 1993 article entitled "Overpressures in the Central North Sea: Implications for Trap Integrity and Drilling Safety", also demonstrate a reasonable partial understanding of the relationships that govern pore fluid pressure in the subsurface. Gaarenstroom et al relate trap integrity to formation strength. While a certain minimum formation strength is required, it is not strength that is regulating the compartment pressure. Very weak shales, salt, as well as very strong impermeable quartzites have very different strengths. All these different strength lithologies can equally well accomplish the job of sealing a pressure compartment as long as they have sufficiently low intergranular permeability.
FIGS. 3 and 4 of the Ward et al 1994 article show the transition between loading and unloading limb stress/strain relationships is related to a low porosity zone within the North Sea chalk interval. The transition between effective stress loading and unloading occurs in this zone. The zone definition is broad and general and does not specify the sealing mechanism or exactly where the seal is located within the low porosity zone. The difference between Ward et al's description and the present invention is that low porosity is coincident with, but is not equal to high fracture pressure. A low porosity rock will have different fracture pressures which also depend upon vertical effective stress and pore pressure. Fracture pressure is the actual force that holds the in situ Compartment Pressure Limit Valve closed.
Ward et al and Gaarenstroom et al have identified two (2) different factors, strength and low porosity which are coincidentally related to fracture pressure under special circumstances. Methods related to these parameters should work in a relative sense under the particular geologic situation they describe. The distinction made here is that when fracture pressure is used as the discrimination parameter, the method works in general because of force balance regardless of these other circumstances.
The relationships described by Gaarenstroom et al, Bowers and Ward et al indicate that they have a general understanding of the factors coincidentally related to the occurrence of pressure compartments, and loading vs. unloading stress/strain relationships. The caprock seal required for unloading can be recognized as a relative porosity low within a sequence as described by Ward et al. Porosity provides a means for recognizing a compartment pressure seal under the specified average regional conditions. But porosity does not provide the means for quantifying the caprock's pressure sealing capacity which controls the pore pressure below.
Seal pressure capacity is the truly important aspect of pore pressure forecasting ahead of the bit. Gaarenstroom et al describe rock strength relationship is likewise a related seal recognition criteria which lacks the means for seal capacity quantification. The solution to these problems lies in the seal mechanism which is not identified in the prior art.
SUMMARY OF INVENTION
The present invention provides an improved technique to more accurately calculate pore pressure of sedimentary rock resulting from subsurface fluid expansion.
There is a static force balance between the total external load applied to a subsurface sedimentary rock and the grains and fluid which compose that rock. All of the external load, which can be described as three (3) principal external confining stresses (S AVE ), is borne by the solid and fluid which compose a sedimentary rock. The fluid in the pore space of a sedimentary rock supports its portion of the external load isotropically as a pore fluid pressure (Pp). The solid grains of a sedimentary rock support the remaining external load which is called effective stress (φ AVE ). The solid phase can support some level of anisotropy between the three (3) principal stresses. Even if the levels of the three (3) principal stresses are not known; the static balance between external (S AVE ) and internal (Pp+σ AVE ) forces is known to be equal as demonstrated by the effective stress theorem in the 1980 article by Carroll, entitled "Compaction of Dry or Fluid Filled Porous Material".
The solid portion of a sedimentary rock is composed almost entirely of a few simple minerals. Each mineral is a crystalline structure having an ordered spacing of ions, and a narrowly fixed chemical composition. The effective stress load is ultimately borne by the mineral ionic bonds. Average ionic bond strength is the main factor controlling the physical and chemical properties of minerals. Knowing the mineralogic composition of a sedimentary rock, places narrow limits on a host of useful related rock physical and chemical properties including compaction resistance and rock strength.
Solidity is the complement of porosity ((1.0-φ)=solidity). Solidity is a very important rock physical property which is also a direct measure of compactional strain for sedimentary rocks. The choice of solidity as the strain definition in conjunction with force balance stress definitions is a particularly useful though hardly used frame of reference in rock mechanics. This combined rock property (solidity=total in situ strain) frame of reference gains one a degree of freedom on many rock and soil mechanics problems. Many rock mechanics interrelationships that have otherwise required measurement control are therein controlled by definition.
The required elements for this new technique are either force balance definitions, material properties definitions, or strain definitions upon which an in situ pore pressure prediction methodology can be built as discussed in the 1996 article by Holbrook. These definitions provide the basis for a rock mechanics system which depends only upon in situ petrophysical and borehole fluid pressure measurements. Stress and strain (solidity) are related through force balance and composition (mineralogy), all of which are indirectly measured in situ with calibrated petrophysical instruments.
There are two (2) significant new developments which are built upon U.S. Pat. No. 5,282,384 to Holbrook. There is an internally regulating interaction between the two (2) force balance variables, fracture pressure and pore pressure in the subsurface. This relationship is an in situ relative force balance corollary to the basic force balance methods disclosed in the above patent.
Identifying a quantifiable force balance seal mechanism is the first step to a more general solution as to when and where to switch between loading limb and unloading limb stress/strain relationships. A force balanced in situ petrophysical measurement adaptive method for triggering the switch is disclosed in this patent. The unloading limb stress/strain relationship is calculated from a calibration well trigger point. The adaptive method assures consistent trigger point placement between planning and drilling wells. The planning well measured unloading limb stress/strain relationship is applied from the drilling well trigger point for pore fluid prediction within a fluid expansion unloading compartment.
The maximum compartment pore fluid pressure limits can also be calculated indirectly from related in situ force balance relationships at the trigger point when the sealing mechanism is known. The new method involves a mechanism dependent transfer of mechanically sensible in situ stress/strain relationships from planning or drilling well in situ petrophysical measurements. The compatible methods for force balanced pore pressure calculation and underlying compartment upper fluid pressure limits will be described below.
Fracture pressure at the free water level of a reservoir is the upper fluid pressure limit for the relative hydrostatic pressures within a continuous reservoir compartment. By projecting caprock physical rock properties and overburden to the free water level, one can thereafter predict the pore fluid pressure limit for the entire pressure compartment using Pascal's Principle. At great depth and in the presence of fluids that have significant thermal expansion potential, most continuous pressure compartments are at this pressure limit.
These and further objects, features and advantages of the present invention would become apparent from the following detailed descriptions, wherein reference is made to the Figures n the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 graphical represents the power law linear loading and unloading in situ stress/strain relationships for shale formations.
FIG. 2 illustrates a continuous fluid pressure compartment having a natural fracture system, caprock Minimum Work Fracture Pressure limit for the pressure compartment, and representative force balanced in situ Rock Mechanics System continuous logs.
FIG. 3 is a program flow chart to identify pore pressure increases associated with possible local sealing fracture pressure maxima.
FIG. 4 is a program flow chart to identify the maximum expected pore pressure in a continuous fluid pressure compartment.
FIG. 5 is a program flow chart to calculate pore pressure using unloading stress/strain relationships.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
U.S. Pat. No. 5,282,384 to Holbrook, which is incorporated herein by reference, is a complete and accurate description of the method to calculate sedimentary rock pore pressure and fracture pressure in Normal Fault Regime-biaxial basins under loading limb stress/strain conditions. In ˜biaxial NFR basins, the maximum principal and effective stresses are vertical; and the two (2) horizontal stresses are approximately equal. The compactional calibrations in this method are derived from in situ loading limb stress/strain (solidity) relationships as discussed in the 1995 article by Holbrook previously mentioned herein. Vertical and the two (2) approximately equal horizontal effective stresses are related to solidity in these basins as described by Equations 6, and 8 of U.S. Pat. No. 5,282,384. Overburden (Sv) and effective vertical stress (σ v ) differ by pore fluid pressure (Pp). This is Terzaghi's uniaxial force balance effective stress law (Equation (2) herein) which is coincidentally proportional to total stress in NFR ˜biaxial basins. More than half of the world's sedimentary basins have ˜biaxial NFR stress fields.
A closed form force balanced stress/strain relationship exists in NFR ˜biaxial basins as described in the 1996 article by Holbrook, because all three (3) principal stresses are directly related to the same measure of volumetric strain (solidity). Sedimentary rocks are mixtures of mineral grains. Only two (2) coefficients (α, and σ max ) are required to relate volumetric stress to strain. These coefficients can be calculated using Equations 4, and 5 of U.S. Pat. No. 5,282,384 as a mineralogically weighted average for all sedimentary rocks as discussed in the 1995 article by Holbrook. The effective stress loading limb relationship for a sedimentary rock of any mineralogic composition is described as Equation 6 of that same patent. U.S. Pat. No. 5,282,384 is the preferred embodiment for obtaining the force balance variables; 1. overburden, 2. effective vertical stress, 3. pore fluid pressure 4. effective horizontal stress, and 5. fracture propagation pressure. These variables are related through force balance in ˜biaxial NFR basins and this natural physical constraint offers many advantages over any other procedure for arriving at the same five (5) variables.
All the other prior art pore pressure and fracture pressure methods depend indirectly on these five (5) physical variables in one way or another. This preferred embodiment description is not meant to exclude any other means of approximating these five (5) variables under any basin or location specific conditions. The reason U.S. Pat. No. 5,282,384 is preferred is that it is exactly physically representative. The known force balanced interdependence of all five (5) variables is a powerful boundary condition which is applicable to location specific conditions within ˜biaxial Normal Fault Regime Basins.
The preferred procedure for defining an unloading limb stress/strain relationship is to relate it to the appropriate loading limb stress/strain relationship, ie. Equation 6 of U.S. Pat. No. 5,282,384. The many possible unloading limb stress/strain relationships shown on FIG. 1 as 10, 11, 12 and 13 can also be expressed as power law functions like Equation 6. At geologic loading rates the loading limb 14 is a physical upper limit to the unloading-reloading limb. Starting from any unloaded point under the loading limb 14 portrayed on FIG. 1, a reloading limb stress/strain path (for example dashed line 10) will be followed until the loading limb envelope is reached, as defined by Equation 6. Further, additional loading will follow the solid Equation 6 loading limb stress/strain path 14 toward the (σ Max ) total solidity intercept.
The preferred point of departure or reattachment of an unloading limb, for example 10, to the loading limb 14 depends upon a physical mechanism in the subsurface. Under most circumstances thermal or hydrocarbon cracking fluid expansion mechanisms produce relatively small volumes of fluid. A very efficient seal is required for this small fluid volume to significantly raise the fluid pressure of a large volume continuous fluid pressure compartment. The high fluid pressure seal must be continuous and unbroken over the top of the compartment in order to be an effective seal. Within a single observation well, a local point of maximum pressure sealing efficiency (low intergranular permeability and high fracture pressure) would be part of the required pressure seal for a continuous pressure compartment.
Owing to Equation 8 of U.S. Pat. No. 5,282,384 a local fracture propagation pressure maximum will correspond to a local porosity minimum which will usually coincide with a local intergranular permeability minimum. Both intergranular permeability and fracture permeability will usually be relatively low in the same place but for different reasons. Open fracture permeability is many orders of magnitude higher than intergranular permeability for rocks that could form effective pressure seals. Fluid escape to the surface through fractures is many orders of magnitude easier than through the grains, so open fractures are the least work path.
FIG. 2 shows a generic pressure compartment illustrating the additional in situ corollary force balance inter-relationships which are part of this new method. The stippled area 15 between the two (2) fractured shale beds 16 and 17 represents a continuous pressure compartment. A pressure compartment is a continuous rock body with sufficiently high permeability to reach a seal relative hydrostatic condition. It can be any size or shape. It is defined by its static fluid pressure property, (i.e.) that pressure everywhere within the compartment is a relative fluid density-elevation relationship which can be calculated using Pascal's Principle. For example, a continuous rock body with an intergranular permeability above 10 millidarcies would equilibrate to seal relative hydrostatic pressure within several thousand years and thus be a pressure compartment.
Caprock seal fracture pressure when applied with Pascal's Principle is the effective upper limit of the maximum pore pressure which can be reached anywhere within an underlying moderate to high permeability pressure compartment. Elevated pore pressure at the Minimum Work Leak Point of the underlying continuous pressure compartment will open fractures in the overlying caprock seal at its fracture pressure and fluid will easily escape until the fractures close. This spatial in situ fracture pressure/pore pressure force balance limiting relationship is general and leads to a new method for forecasting pore pressure below the top petrophysical sensor of a Measurement-While-Drilling tool string of the type known in the art based upon those sensor readings.
Inset circle 18 in the upper left of FIG. 2 represents a single vertical fracture perpendicular to the minimum principle stress within the caprock 16. The opposing arrows in all three (3) inset circles 18, 19 and 20 represent the minimum principal stress which has a magnitude proportional to the effective vertical stress in ˜biaxial Normal Fault Regime basins. A tensile fracture with no shear offset will be closed if the pore fluid pressure within the fracture is less than or equal to the caprock fracture pressure.
The Minimum Work Leak Point, illustrated in 19, for a pressure compartment shown on FIG. 2 is just below the hydrocarbon water contact. If there are no hydrocarbons, and the caprock 16 has uniform petrophysical properties, the caprock Minimum Work Leak Point is at the highest elevation of the pressure compartment. The force balance at the pressure compartment--caprock interface changes systematically with overburden and elevation in FIG. 2 as it does with any pressure compartment.
The fluid pressure within the compartment changes in direct proportion to average fluid density/elevation (Pascal's Principle). For subsurface brines this fluid pressure gradient is somewhere between 0.434 to 0.507 psi/foot. The change in fracture pressure with elevation is somewhere within the range of 0.9 to 1.15 psi/foot. This force balance relationship depends on caprock porosity, overburden and pore pressure. The compartment pore pressure limit is much more dependent on overburden than it is on caprock porosity.
Starting from the lowest caprock seal point of a continuous pressure compartment and progressing upward, the sealing caprock fracture pressure decreases about twice as fast as the compartment pore pressure. A relatively uniform caprock 16 is about 0.5 psi easier to fracture with each foot of gained elevation. The caprock Minimum Work Leak Point is where the compartment pore fluid pressure is highest with respect to fracture pressure in the overlying caprock. At that point, there are no additional capillary forces to overcome to open a fracture if the fluid in the compartment and the fracture are equally wetting.
However, if the compartment pore fluid contains hydrocarbons and the fracture surfaces are water wet, a considerable additional capillary resistance must be overcome for the two-phase fluid in the reservoir to enter the water wet fracture. The additional pressure needed to force a two-phase fluid into a capillary size fracture is usually two times or more greater than the single phase pore fluid entry pressure. In general the capillary entry pressure for a hydrocarbon increases much faster than the slight additional pressure resultant from hydrocarbon/water density contrast. The increase in work required to force the two-phase fluid into the fracture is much greater than the slight decrease in fracture pressure that accompanies the change in overburden and elevation.
The relevant force balance affecting pore pressure, fracture pressure, capillary pressure and overburden are covered in the discussion above and their approximate magnitudes quantified. Tensile fractures are pervasive in the subsurface particularly where pore pressures have been elevated in the past. Considering all these together, the Minimum Work Leak Point for the pressure compartment will normally be very near the highest single-phase fluid elevation.
The above discussion omits the issue of compartment pressure communication through open faults. If an open fault cuts the pressure compartment anywhere, top or side; the open fault is the minimum work compartment pore pressure regulating mechanism. Open faults can only lower the compartment pore pressure below that of the caprock Minimum Work Leak Point for the pressure compartment. Even a perfectly sealing fault cannot exceed this. In a geologically short time, minerals are deposited in the open spaces within a fault zone. In the absence of continued fault displacement, cement deposition lowers fracture permeability gradually and returns the open fault to a closed sealing condition. When fault sealing is complete, the Minimum Work Leak Point again becomes the continuous compartment pressure limit.
Though perhaps not immediately obvious from the above discussion, fracture pressure derived while drilling can be used as an effective pore pressure limit predictor at or ahead of the bit. The drilling decision of whether or not an additional casing string is required depends upon the maximum pore fluid pressure expected below. Drilling can safely proceed through the underlying continuous pressure compartment without setting casing if the maximum expected pore fluid pressure within the compartment is less than the minimum open hole fracture propagation pressure.
The Measurement-While-Drilling petrophysical sensors, of the type known in the art, on a typical drill collar are usually placed as close as possible to the bit. This distance is often as little as twelve (12) feet. The increasing fluid pressure transition zone below a sealing caprock 16 is usually tens to hundreds of feet thick. In the well being drilled, fluid pressures within a pressure compartment ahead of the bit vary according to Pascal's Principle. The geometry and continuity of pressure compartments are known or inferred before an oilwell drilling location is selected. Garrenstroom et al in their 1993 article produced a map of the expected pressures and compartment lateral boundaries for a large part of the Central North Sea. A new well is generally drilled to find and produce hydrocarbons and there is an expected if not known hydrocarbon water contact.
As the well is drilled, geologists keep track of bottom hole location, and the stratigraphic interval being penetrated. Drilling fluid density is adjusted to be within a "Safe Drilling Window" which is defined by the drilling fluid density range between the maximum open hole pore pressure and the minimum open hole fracture pressure. It would be extremely valuable information if the driller could know the maximum pore pressure that can be expected before entering the next pressure compartment below. Another casing string will be required if the maximum pore pressure in the underlying compartment is above the minimum open hole fracture pressure. The maximum fracture pressure at the Minimum Work Leak Point for the pressure compartment calculated in combination with Pascal's Principle is the pore fluid pressure limit for the entire compartment.
FIG. 2 defines the unloading limb sealing mechanism as a relative force balance phenomenon. A local maximum fracture pressure can be defined from a continuous fracture pressure log. The trigger point-transition from loading limb to unloading limb stress/strain relationships would necessarily occur at some local fracture pressure maximum. A local fracture pressure maximum can be calculated directly from in situ strain data using a combination of Equations 7, 8, and 9 in U.S. Pat. No. 5,282,384 to Holbrook.
The opening and closing of minimum work fractures in rocks is controlled by Equation 9 of U.S. Pat. No. 5,282,384 force balance. D'Arcie flow to the surface operates independently of permeability type always following a least work path. As the method for establishing the maximum pressure sealing efficiency point is coincident with the point of departure from the loading limb, it will be described in detail first.
FIG. 3, is a logical flowchart to identify pore pressure increases associated with possible local sealing fracture pressure maxima. FIG. 3 describes a pair of binary decisions which, when executed with each successive True Vertical Depth (TVD) increment, will discriminate possible higher fluid pressure sealing fracture pressure maxima from those which are not. FIG. 3 describes a computer algorithm, which can be executed using TVD data from either file input or real-time drilling. Operations START, Check for Exit, Data retrieval, and END are external computer control operations which are not primary elements of the compartment seal recognition process. Recognition of possible pressure compartment seals is accomplished by the two decision diamonds 21 and 22 portrayed executed in series as shown in the flowchart.
The first decision diamond 21, "Fracture pressure change over 5 feet", defines whether a fracture pressure maximum has been reached or not by comparing successive values. If the estimated fracture pressure of the present point is greater than or equal to the last point, a locally deepest fracture pressure high has not been reached. There is no reason for further seal evaluation in this case, so control is passed to the "save last pressure", process box 23 and the next successive TVD set of data points is retrieved for comparison.
Following retrieval of the next set of data points, the same decision diamond 21, "Fracture pressure change over 5 feet", is encountered making the same decision on the next successive foot. This loop continues until the first falling fracture pressure data point is encountered. Dotted box 24 is on the logic flowpath, but is not a process. Box 24 indicates the fact that, "A possible sealing fracture pressure maximum has been penetrated". At this point the TVD set of data points is an unconfirmed candidate seal. But, the first short decision loop alone has eliminated most data points from seal candidacy.
The next decision diamond 22 encountered on the "Less" side of the first decision diamond 21 is "Pore pressure gradient change from 5 feet above seal". Here the comparison is made between the slope (ΔPp/ΔTVD) of successive pore pressure estimates to determine if there has been any change within or across the candidate seal. There are two (2) possible alternatives of this binary comparison which are also shown on the logic flowpath in dotted outline boxes 25 and 26. Again these are not part of the process, but indicate the state of fracture pressure/pore pressure relationships at that point in the logical flowpath.
If the pore pressure gradient is "Less than or equal to", the previous TVD pore pressure gradient; the "Previous fracture pressure maximum did not cause an increase in pore pressure gradient", box 25, condition exists. The existing pore pressure trend is no greater than that above which may have been controlled by a loading limb stress/strain relationship. Most local fracture pressure maxima have a pore pressure gradient below which is no higher than the pore pressure gradient above. These data points are also eliminated as candidate seal points and the program loops back up to retrieve the next successive TVD set of data points. The left, "equal or less" half of this decision flowchart will always result in the elimination of a TVD dataset from candidacy as a possible unloading limb fracture pressure seal.
The only remaining possibility of this decision flowchart is that the, "Pore pressure gradient has increased under a possible fracture seal", box 26. This is a very important observation which triggers the next two process control operations. If the "Greater than" condition is met in the "Pore pressure gradient change from 5 feet above seal" decision diamond 21; the computer program or individual monitoring the changes in data should, "Save the last maximum fracture pressure, pore pressure, and TVD into a possible seal file", box 27. If these two (2) data comparisons are made by a computer program, the next step 28 in the process is to, "Display the last possible unloading limb seal depth and a warning to a computer terminal".
Increasing pore pressure gradient below a candidate seal is indicative of more dangerous drilling conditions below regardless of the fluid pressurization mechanism. The loading limb calculated pore pressure is a minimum expected pore pressure value for this TVD. From this point onward pore fluid pressure will either increase at the effective stress loading limb rate or faster. If pore pressure under a possible fracture pressure seal is increasing at a faster than previous (ΔPp/ΔTVD) rate the operator should consider fluid expansion unloading as a possible additional pressurization mechanism and act accordingly.
The above described flowchart eliminates over 99% of the total drilled footage in any well from the candidate unloading limb fluid expansion pressurization category. The decision as to whether to shift to an unloading limb stress/strain relationship, and what that relationship most likely is should be made at this time.
The dual High Temperature, High Fracture Pressure conditions that lead to fluid expansion unloading are usually consistent within a local area. The methods of Bowers and Ward (1994) can identify the general areas and depth ranges where fluid expansion has definitely forced the subsurface stress/strain relationship onto the unloading limb. Their post facto methods of analysis also provide a reasonable estimate of the relative slope of the in situ unloading limb stress/strain relationship within a region and depth range.
The procedure described in FIG. 3 identifies which relative porosity low and consequent fracture pressure high is the seal within the caprock containing possible fluid expansion pore pressure. If the candidate unloading limb fracture pressure TVD falls within a depth window roughly defined by a Bowers or Ward method, the operator should seriously consider switching to an unloading limb stress/strain relationship at the most likely sealing point.
The methods for determining the maximum expected pore fluid pressure within an underlying continuous fluid pressure compartment, and a more accurate method for determining the slope of regional (ΔPp/ΔTVD) gradient using the same five (5) physical variables will be described below.
FIG. 4 is a flowchart describing the fixed process steps which should be taken to calculate the maximum expected pore pressure (Ppmax) that would occur anywhere within a continuous pressure compartment based upon an observed caprock fracture pressure above the minimum work compartment leak point (Pf@lp). FIG. 4 shows the procedure that corresponds to the general caprock to compartment physical-spatial relationships shown in FIG. 2.
The stepwise procedure described in FIG. 4 can be applied every time one penetrates an observed local fracture pressure maximum during the drilling of a borehole into the Earth. Typically, the distance between a fracture pressure maximum in a sealing caprock and an underlying continuous pressure compartment is 50 feet to 500 feet. Typically, the offset between the top petrophysical sensor in an MWD drillstring is less than 20 feet. The 30 feet plus margin is sufficient so that casing can be set in the low permeability caprock before the drill bit actually penetrates into the potentially dangerous higher permeability continuous fluid pressure compartment. Casing cemented across the highest fracture pressure in the caprock will provide the maximum margin of safety when initially penetrating the underlying continuous pressure compartment.
There are two (2) basic steps in the procedure for calculating the pressure limit everywhere within a continuous pressure compartment shown on FIG. 4. The first basic step is to calculate the minimum work caprock fracture pressure for the underlying compartment. The first ten (10) process steps, 30 through 39, are surrounded with solid line boxes lead to the heavy line process box 40 where this calculation is made.
The second basic step which applies Pascal's Principle to calculate pore pressure anywhere in the compartment has three (3) sub steps, 41, 42 and 43, whose process box outlines are dashed lines leading to heavy line process box 44. The fundamental process involves calculating the five (5) critical force balance variables from a measurement well profile penetrating the continuous pressure compartment. The solid rock related force balance variables, effective vertical and horizontal stresses are projected from the Tangent Overburden gradient in the measurement well profile. These values are projected to the expected True Vertical Depth of the Caprock Fracture Pressure Maximum above the expected hydrocarbon/water contact of the compartment. This provides a quantitative value for the force holding the pressure valve closed portrayed in the left blowup circle 19 on FIG. 2. Maximum fracture pressure at that Minimum Work Leak Point for the pressure compartment sets the proportional limit for the entire compartment.
The static fluid pressure proportionality function is Pascal's Principle which is a simple linear function of elevation and average fluid density (ρ f ) from the Minimum Work Leak Point for the pressure compartment. Subsurface waters are very close in composition to Sodium Chloride brines. The density of subsurface brines are often available from direct fluid density measurements of water produced from nearby oilwells. If these measurements are not available, the density of NaCl brines can be calculated with 0.01 g/cc accuracy from PVT-NaCl salinity relationships, as described in the 1987 article by Kemp.
The in situ density of oil and gas under various pressure, volume and temperature (PVT) conditions is also routinely calculated for reservoir production purposes. Repeat formation pressure measurements are frequently made within producing reservoirs to determine the in situ formation water pressure gradients (wgrad); or the in situ partially hydrocarbon saturated fluid pressure gradients (dgrad) directly.
The uncertainty in fluid density plays a very small role in the overall calculation scheme portrayed in FIG. 4. Fluids occupy only a small volume fraction in a sedimentary rock and fluid densities span a fairly narrow range. The variability the in four (4) solid rock related pressure gradients is much more important to the outcome of the overall calculation scheme. The selection of a good and representative tangent Overburden Gradient (step 32 of FIG. 4) is probably the most important step of the procedure from an overall quantitative output point of view.
The most significant factor affecting fluid expansion pressurization is the regional geothermal gradient. Higher geothermal gradients lead to greater fluid expansion with depth and steeper unloading limb effective stress relationships. Both the in situ loading and unloading limb stress/strain relationships are very steep. The loading limb effective stress slope is 83.46 degrees for shale, 85.67 degrees for rounded pure quartz sandstones and 85.66 degrees for rounded calcite grainstones.
The unloading limb effective stress/strain relationship for each of these minerals is steeper. At 90 degrees the stress/strain slope is undefined. The relative unloading limb stress/strain relationship is calculated in degrees so that a change in the unloading factor (UNL -- FACT) will have a proportional change on calculated effective stress and pore pressure. The unloading limb factor is limited between 0.0 degrees which is coincident with the loading limb, and 4.19 degrees which coincides with the highest real number sigma max intercept which can be stored as a real number in a computer. Unloading factor values outside of this range are not allowed. This computer memory upper limit corresponds to a slope limit of 89.993 degrees which should not affect any real unloading limb calculations. The maximum expected real number slope using known maximum sediment porosities is 89.86385 degrees.
Given a very high fracture pressure seal, the unloading limb factor seems to vary within a narrow range (˜0.02 ) degrees within an area of several square miles. The unloading limb factor is consistently higher in higher geothermal gradient areas and lower in lower geothermal gradient areas. There is not much unloading limb data at this time and all of the unloading mechanisms are not sufficiently well understood to go further. What can be said is that if the procedure described in the following flowchart is followed for several wells in a local area, the same unloading limb factor produces equally good results in all local area wells.
The method described in FIG. 5 involves a more precise physically descriptive identification of seal depth which can cause the onset of fluid expansion unloading. In FIG. 5 the seal is identified and quantified by its high fracture pressure which is additional valuable information. The flowchart also provides a means for re-setting the mineralogic unloading limbs in case the operator errs in placing the estimated seal depth too high. This feature makes the overall procedure useful for real time drilling operations. The flowchart of FIG. 5 encapsulates how, where, and why one would switch from loading to unloading stress/strain relationships for pore fluid pressure calculations. The slope on the loading limb stress/strain relationships appear to be global constants which are only a function of average sedimentary rock mineralogy as described in the 1995 article by Holbroolk. The slope of the unloading limb stress/strain relationship is related to regional geothermal gradient, and must be determined for the local region.
Referring to FIG. 5, therein is described the preferred procedure. In FIG. 5 there are four (4) decision diamonds 45, 48, 54 and 56 on the program flowchart. The first two 45 and 48 involve operator choices, the second two 54 and 56 are objective choices which can be made by a computer based upon comparison of successive True Vertical Depth data values.
Steps 46 and 47 of the flowchart summarize the steps of calculating the critical five (5) force balance variables from successive petrophysical measurements. The method described by Holbrook, U.S. Pat. No. 5,282,384 is preferred, but any other procedure for acquiring the same five (5) force balance variables is not excluded.
The program operator must set the program onto the unloading limb at a depth based upon local experience in a given area 48. The preferred depth should correspond to a high fracture pressure seal. These seals are usually related to stratigraphic depth, but continuous diagenetic seals have also been suggested. At the expected onset of fluid pressurization unloading, the operator turns on an unloading limb calculation switch 48 which leads to the next lower part of the program flowchart. The operator also provides at this time, the unloading limb factor which is the number of degrees between the loading and unloading limbs in the local area 49.
The depth of a fracture pressure high in the probable seal is responsible for containment of fluid expansion pore pressure. The power law linear loading and unloading limbs intersect at that point. The porosity, mineralogy, and force balance variables at that depth are transferred to solve for the slope and intercept of the unloading limb given the unloading limb factor, step 50.
The unloading stress/strain (solidity) slopes for each end member mineral are preceded with "UNL -- A -- ", with the described mineral descriptor attached, step 51. The stress/strain solidity=1.0 intercept of the power law function for each end member mineral are all labeled with the prefix, "UNL -- Smax -- ", with the described mineral descriptor attached. The program reserves a low and high "UNL -- Smax -- " memory location which are set to the same value at 52. The high and low memory locations will be used subsequently if the operator has made an incorrect estimation anticipating the peals fracture pressure.
A peak, thermal expansion fluid pressure "Pth", is calculated from the average Geothermal gradient of the area, step 53. The average geothermal gradient is supplied by the operator, step 46. The depth difference between the "TVD Seal", and the present "TVD" depth of a sample provides the temperature difference needed for the calculation. The thermal expansion coefficient "Texp", for a Sodium Chloride brine under the existing pressure temperature conditions is used.
Following this step the program makes a data comparison 54, to determine if the fracture pressure at the present TVD is greater than the previous maximum fracture pressure "Pf max", which is held in computer memory. If the fracture pressure is less than "Pf max", there is probably no change in the unloading limb status. If on the other hand, fracture pressure has increased above the previous maximum, "Pf max", and "TVD Seal" are reset to the new higher values, step 55.
In either case the program proceeds to the next decision diamond 56, ie. "Is "Solidity" greater than the previous Solidity max", which is held in computer memory. Again if "Solidity" is less than the previous "Solidity max", the present mineralogic unloading limb slopes "UNL -- A -- ", and stress/strain solidity=1.0 intercept, "UNL -- Smax -- ", are still appropriate for calculating Pore Pressure from Effective stress and strain (Solidity), step 57.
If however, "Solidity" has increased above the previous "Solidity max", which is held in computer memory, the peal, sealing fracture pressure has not been reached. This is the "Yes" exit to the decision triangle which leads to a different calculation procedure for pore pressure "Pp", and a re-setting of the unloading limb stress/strain coefficients "UNL -- A -- ", and "UNL -- Smax -- ", effect is accomplished as shown in the process block 58, which is repeated for each mineralogic end member. Process block 58 corrects the unloading limb to account for the higher than expected seal fracture pressure "Pf" which will be applied to the next calculation.
Effective stress "Est" is calculated from the old "Smax" set of coefficients, step 59. There probably was some increment of thermal expansion since the last estimated seal depth in this case. That increment of additional pore pressure "Pth" is then added in the next process calculation 60.
A final pore pressure comparison 61 is made to determine if the calculated pore fluid pressure gradient, "Pp" has exceeded the previous maximum fracture pressure gradient "Pf max" which was held in computer memory. If so, then the calculated pore pressure is reduced to that fracture pressure gradient. This is the theoretical force balance limit if the fluid contained in the pressure compartment is water.
The program then displays and stores all calculated force balance variables and cycles back to gather more petrophysical data. This is portrayed by the return looping arrow 62 on FIG. 5. This step is executed in the same manner whether on the loading or unloading limb. The process continues until the program either runs out of data or is terminated by the operator. The overall process described in this preferred embodiment has described a method wherein an operator can calculate pore fluid pressure using mechanically sound force balance relationships using appropriate physical constraints whether the pressure driving mechanism is disequilibrium compaction or unloading fluid expansion.
The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and various changes in the methods and techniques described therein may be made within the scope of the appended claims without departing from the spirit of the invention. | An improved technique to more accurately calculate pore pressure of sedimentary rock due to subsurface fluid expansion where the technique is built upon a combination of known force balanced in situ loading limb mineralogical stress/strain relationships with locally variable unloading stress/strain relationships, including that in stress/strain space, the material properties governed loading limb is an upper limit for the many possible unloading limbs; also, a method for relating these different natural stress/strain paths and applying the correct path to calculate pore fluid pressure from in situ force balance is disclosed such that the method is preferably calibrated with in situ stress/strain data which allows for a lithologic sealing caprock to be identified and the locally prevailing in situ unloading limb stress/strain relationship to be estimated, where the forced balanced loading and unloading calibrations are applied to more accurately determine well casing depths using either wireline or real-time "measured while drilling" petrophysical data; and also solidity (1.0--Porosity) is the in situ parameter of choice which can be measured petrophysically in the borehole, where pore pressure is the fraction of the total external load which is borne by the fluids in the pore space of a sedimentary rock, and the solid framework of a granular sedimentary rock bears the force balance remainder of the external confining load as effective stress; so that loading and unloading power law linear stress/strain relationships are determined between effective stress and solidity for common sedimentary rocks. | 4 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention pertains to a high-precision radar range finder, whose design corresponds to the FMCW principle, the radar range finder operating in a frequency range of 24.125 GHz±125 MHz, the range finder being particularly useful for closed containers.
Besides other fields of use, this device is preferably used in the level measuring technique. A great variety of designs of level meters have been known. The contactless level metering methods are based, besides radar methods, preferably on the travel time measurement in the ultrasound range or in the laser range. The ultrasound sensors have the drawback that the velocity of propagation of sound changes with the medium whose level is to be measured, as a result of which very substantial errors in measurement occur. The laser sensors have the drawback that, aside from the high purchase price, the level cannot usually be recognized in the case of clear liquids, because the laser beam is reflected from the bottom of the container rather than at the level. The radar sensors are free of these drawbacks.
The requirements imposed on a radar sensor are, aside from the high degree of reliability required, the measurement of the level to an accuracy in the cm range. Compliance with various regulations is required including specified frequency bands (FCC in the U.S.A. and FTZ-German Federal Central Bureau of Telecommunications) and others (e.g., approval by the German postal administration, as well as compliance with the protection requirements of the German Federal Institute for Physics and Technology, Group 3.5 "Explosion Protection of Electrical Equipment").
SUMMARY AND OBJECTS OF THE INVENTION
To reach an accuracy of measurement in the cm range, the transmitted signal is modulated either in the time range or in the frequency range. In the case of pulsed systems, extremely short pulses corresponding to the equation
accuracy of measurement=velocity of light·pulse length/2
are required for this. At an accuracy of measurement of, e.g., 10 cm, this would correspond to a pulse length of 0.66 nanosec. This cannot be economically achieved for industrial applications with the technology currently available.
In the case of frequency modulation of the transmitted signal, the range resolution is determined by the modulation bandwidth, (deflection from the center frequency) according to the equation
accuracy of measurement=velocity of light/(2·modulation bandwidth).
At an accuracy of measurement of, e.g., 10 cm, this would correspond to a modulation bandwidth of 1.5 GHz. This can be accomplished economically for higher frequencies, and the frequency approved for this application is 24.125 GHz, but the requirement of the German postal administration in terms of a band limitation of 24.125±125 MHz for the general FTZ approval is not met. The modulation bandwidth is reduced step by step, from one measurement to the next, beginning with the maximum allowable bandwidth (250 MHz).
The modulation method is shown schematically in FIG. 2. To determine the range between the level and the measuring apparatus, a spectral analysis of the received signal is performed by means of a discrete Fourier transformation. The relationships are represented in FIG. 3.
However, if general approval by the postal administration is not required, e.g., in closed containers, accuracies of a few mm can be reached according to the method described at a bandwidth of, e.g., 1.5 GHz.
The primary object of the present invention is to provide a high-precision radar level meter, which operates according to the FMCW principle with digital signal processing for high-precision range measurement with limited frequency shift.
According to the invention, a radar range finder is provided which is designed using the FMCW (frequency modulated continuous wave) principle and which operates in the frequency range of 24,125 GHz±125 MHz. High precision range determination is performed using means for determining the optimal or adapted frequency shift in a stepwise manner. Structure is provided for approximately determining the allowable shift, after which the shift is successively broken down until an integer multiple of range gates generated corresponds to the exact distance between the measuring apparatus and the reflection surface. The maximum amplitude of the spectrum or the minimum of the sidelobes of the measurement sequence is used as the indicator of the optimal or adapted shift. A control loop is provided including an oscillator, a directional coupler, a divider chain, a counter as well as a microprocessor and a digital to analog converter with a frequency which is formed having an integer multiple which is the actual transmitted frequency.
A video device is provided with a device for level processing and is coupled with a controllable amplifier, controlled by the microprocessor and with means for band filtration. The oscillator (preferably a voltage controlled oscillator) is followed by an amplifier which is optimized for generating a fifth harmonic of the oscillator frequency. The amplifier is associated with the band filter for the fifth harmonic of the oscillator frequency and with an additional amplifier for raising the level and for decoupling. The transmitted signal is separated from the receive signal by a directional Coupler. The receiver has an LO buffer amplifier and a mixer which are manufactured according to the highly integrated technology (monolithic microwave integrated circuit). To convert the voltage controlled oscillator frequency into the MHz range, a divider chain with a plurality of divider steps is arranged in the control loop. The divider chain is part of a control loop, which performs an auto calibration cycle on the oscillator.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic view of a level measurement by a radar level meter;
FIG. 2 is a modulation/bandwidth-time diagram of the modulation method,
FIG. 3 is a diagram for range determination from the spectrum of the received signal;
FIG. 4 is a schematic diagram of a discrete measurement of the range by distance gates;
FIG. 5 is a diagram for superimposing different spectra at different frequency shifts (B x );
FIGS. 6a-6d are diagrams of spectrum/echo profiles with different frequency shifts (B); and FIG. 7 shows a block diagram of an exemplary embodiment of a radar level meter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The discrete Fourier transformation of a time signal quasi breaks down the detected range into so-called distance gates, also called range gates, as is illustrated in FIG. 4, and each range gate corresponds to one spectral line, as is shown in FIG. 3.
In the case of level measurement, it is necessary to deal with a single, dominant "reflector," namely, the surface of the filling material, as can be determined from FIG. 1. All other reflectors, e.g., container wall, etc., are not located in the major lobe of the antenna and therefore they are only very weakly noticeable, if at all, in the received signal.
The following method of high-precision range determination is proposed for this special case:
The echo amplitude of the received signal reaches its maximum precisely when a suitably large range gate is found, so that the range gate can be placed exactly n times between the measuring apparatus and the reflector surface.
The detection method is carried out as follows:
The process is begun with the maximum allowable shift of 250 MHz corresponding to the extension of the range gate, equaling 0.6 m. The apparatus first approximately determines the range. Depending on the approximate distance determined, the range of reduction of the shift as well as the step size from one measurement cycle to the next are subsequently set. The shift is then reduced stepwise, from one measurement to the next, until the extension of the range gate fits exactly n times into the range between the measuring apparatus and the level. This is determined by determining the maximum of the spectrum of the measurement series (cf. FIG. 5), after which the range is calculated from the simple equation
R=Fb·c/(2·B·Fm)
in which:
R=range,
Fb=beat frequency (corresponding to the position of the echo amplitude in the spectrum),
c=velocity of light,
B="optimized" or adapted frequency shift, and
Fm=modulation frequency (cf. FIG. 2).
The sequence of FIGS. 6a through 6d shows how the secondary lines in the spectrum decrease in the course of the stepwise optimization or adaption of the shift. Consequently, the signal energy is concentrated onto the principal line, so that it is "maximal" in the case of the optimal shift bandwidth.
Consequently, the accuracy of the range is no longer determined by the maximum possible shift alone in this process, but mainly by the accuracy with which the optimal shift is determined. This depends, above all, on the selected step size, i.e., the maximum allowable measurement time.
It should also be noted that the shift can be set with high accuracy, and that the frequency modulation should be performed as linearly as possible in order to minimize the side lines represented in FIGS. 6a through 6d, which is made possible by the frequency generation method described below.
As is illustrated in FIG. 7, the voltage-controlled oscillator (VCO) 1 generates the basic frequency of 4.825 GHz. This oscillator signal is amplified in the buffer amplifier 2 following it, and the oscillator 1 is at the same time decoupled from additional steps in order to avoid the so-called pulling effect, which would lead to a deviation from the linearity of the frequency shift and consequently to an inaccuracy in range determination.
The buffer amplifier 2 operates in the saturation mode, thus generating frequency components at multiples of the basic frequency. It is designed to be such that the fifth harmonic (24.125 GHz) is particularly salient. The directional coupler 3 (20 dB) is dimensioned for the fundamental wave, and it decouples the VCO signal to the divider chain 4, 4a with a suitable level. The divider chain 4, 4a, which consists of a plurality of divider stages, converts the oscillator frequency into the MHz range. The control loop is closed via a counter 5, a microprocessor 6, and a D/A converter 7 for the required linearization of this frequency. This control loop makes it possible to eliminate both aging effects of the components and temperature-dependent long-term drifts of the frequency of the oscillator 1 via an autocalibration cycle. The fifth harmonic of the oscillator basic frequency of 24.125 GHz, which is already preferably generated, is selected with the band filter 8, and all other multiples as well as the fundamental wave are suppressed.
The level is processed once again in a connected power amplifier 9 and additional decoupling of the oscillator unit from loaded impedances is achieved at the same time.
The transmitting/receiving unit of the radar level meter proposed here has a directional coupler 11 (10 dB), which decouples part of the transmitted signal for the receiver. Its transmitting branch main arm leads directly to the 6-dB directional coupler 12, which separates the transmitted signal and the received signal. The level of the decoupled part of the transmitted signal is raised in the LO buffer amplifier 13 in order to achieve optimal level control of the mixer 14. The received signal enters the mixer 14 from the antenna via the 6-dB coupler 12, and the video signal is formed in the basic band (beat signal) due to so-called homodyne frequency conversion at the IF (intermediate frequency) output of the mixer 14. This beat signal is subjected to low-noise amplification in the subsequent IF amplifier 15, and decoupling of the mixer 14 from the subsequent filters and amplifier stages of the video part 16 is also achieved at the same time. This video section is used essentially for level adaption and frequency filtering for the A/D converter 17 in the microcomputer 6, in which the control of the overall system, as well as the signal processing, and the range determination are performed.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | The present invention pertains to a radar range finder for high-precision, contactless range measurement, which is based on the FMCW principle and operates with digital signal processing at a limited frequency shift. One exemplary embodiment is described. | 6 |
RELATED PATENT APPLICATION
This application is related to co-pending U.S. patent application Ser. No. 07/379,323 filed Jul. 12, 1989, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates generally to piling and pile driving and more particularly to an improved piling connector and a unique method of connecting pilings. It is equally adaptable to both new construction and for repairing existing construction, and has particular utility in the repair of concrete slab foundations on pilings. Similarly, it is applicable in all terrain conditions in which pilings are used but has particular utility in the most difficult conditions such as saturated soils and terrains in which the water content exceeds complete saturation.
The problems which the present invention overcomes are long-standing and have been known for decades if not longer. For example, friction pilings of the type and size for which this invention is expected to be frequently employed typically might have a ten ton maximum rating. That is to say, such pilings typically are not able to resist a total downward force in excess of twenty thousand pounds. If the environment in which such pilings are to be used is expected to produce a downdrag force of two tons, the pilings may be analyzed as consisting of a two-ton downdrag portion and only an eight-ton frictional resistance portion. The conservative designer will then subtract the two tons of downdrag force from the eight tons of frictional resistive force to obtain a net maximum of six tons per piling and then, in order to have a reasonable margin of safety, use one-half that number, or three tons, as the design capacity of such pilings. Knowing the maximum load which the particular foundation must support, the designer would then calculate the number of pilings needed and distribute that number about the foundation.
The difficulty with super-saturated soils, and even in many soils that are less than saturated but near saturation, is that such soils usually will not remain uniformly wet. When dry, or even when only partially dry, such soils experience enormous contractions, and as they settle, extremely strong downward forces are created. When the downdrag exceeds the maximum resistive force of the friction pilings, failure results.
Due to the difficulty of access, repair of such a failed foundation is typically quite expensive. For reasons of economy, most friction pilings are wooden poles or, literally, de-barked trees. To prevent decay, and subsequent foundation failure as a result therefrom, wooden pilings are commonly treated with preservatives. However, full-length treated pilings typically cost from twice as much as untreated pilings of the same length and diameter, up to three times as much.
Generally, the deeper a piling is set, the greater is its capacity to resist downward forces. In fact, it is not at all uncommon for the resistive force or resistive capacity of such pilings to increase in a non-linear manner with depth. A typical soil profile in which pilings are normally used may provide three tons of resistive capacity at thirty feet of piling length, four tons at forty feet, but perhaps eight tons at sixty feet. Thus it is apparent that the deeper the designer places the pilings, the greater the capacity, perhaps non-linearly greater, and the fewer the number of pilings needed. Offsetting this advantage, however, is the fact that the longer the one-piece piling, the greater is the cost—also a non-linear function. If the installed cost of a treated thirty-foot residental or light commercial piling (e.g., a Modified Class Five piling) in a particular locale is fifty-two dollars, for example, the cost for a forty-foot piling might be seventy-five dollars, and the nearest comparable sixty-foot piling, three hundred thirty dollars.
The dramatic increase in costs for exceeding forty feet is due to several factors, one of which is that the piling material itself must be of a larger class in order to achieve the desired length; this necessitates a non-linear increase in the cost of the material employed. In addition, small “house rigs” can be used to drive pilings up to forty feet; the costs for driving piles with such equipment is typically as low as fifty cents per foot. Going beyond the 40-foot limit, however, exceeds the capacity of such small equipment; much larger driving rigs must be used, the cost of which may be as much as five dollars per foot. Combined with the non-linear cost-of-material increase, the final, installed cost of a sixty-foot piling might typically be as much as four or five times the final, installed cost of a forty-foot piling.
The cost for treating extra-long pilings also increases non-linearly because of the more expensive equipment needed to treat such pilings. It is known that a piling need not be treated along its entire length in order to preserve it; only the portion above the lowest water table need be treated. However, since most treatment means call for the preservatives to be forced into the wood pores under high pressure, and since the non-uniformity of the raw materials makes consistent sealing around the circumference of the work pieces difficult to achieve, equipment which will pressure-treat only an end of a piling is typically either not available or so expensive as to not afford any savings.
The prior art has therefore looked to various means of connecting shorter pilings, i.e., each of forty feet or less, so as to make an effective and economically affordable longer piling. One such early attempt is that of U.S. Pat. No. 1,073,614, “Pile Splice”, to W. A. McDearmid. McDearmid employs a specially-cast tubular body with an integral transverse partition dividing the body into two chambers of equal diameters. The device is placed over a snugly fitting lower pile, a short pin is driven longitudinally into the lower pile with one end protruding, the upper pile is then dropped into the upper chamber onto the pin, and a bolt is then passed horizontally through each chamber and secured by a nut on the distal end thereof. Several disadvantages are presented by this approach, however. One such disadvantage, if the holes in the pilings are pre-drilled, is the difficulty of precisely aligning the holes in the environment intended, i.e., under water or in semi-watery mud. If the holes are not pre-drilled in the pilings, it is virtually certain that a bolt secured through the piling in that environment would often not meet the opposite hole in the chamber.
Perhaps a greater disadvantage of the McDearmid splice, however, is the necessity to adapt or pre-prepare the ends of the pilings to be received in the connector. Not only is this step an additional expense, but if the pilings do not fit quite snugly within both chambers, there will be a tendency for the splice to act not like a rigid connection but pin-like about one or both horizontal bolts until further rotation is prohibited by the walls of the chambers. At this point an eccentricity—perhaps a destabilizing eccentricity—will already have been introduced into the system. The amount of resistance which the small, vertical pin would provide to such a moment is expected to be negligible.
Another approach is that of U.S. Pat. No. 4,525,102, “Timber Pile Connection System”, to Gerard J. Gillen, which also discloses a number of other prior approaches to this problem. Gillen appears to call for a hollow splice to be driven internal to each piling with a confined levelling material therebetween to avoid point or edge stresses and to distribute the forces at the interface more widely. Such an internal splice is of course at least partially destructive of the piling material. In addition, the piling itself becomes the “weakest link” in that only a small fraction of the piling material remains exterior to the splice to hold the splice in place. A small error in aligning the splice along the longitudinal axis could easily cause failure during subsequent driving.
Further, it is apparent that the technique of Gillen will not produce a rigid mechanical joint. The joint will be held together only by the force of friction between a piling end and the connector, and once that resistive force is exceeded, the joint will be expected to come apart. This is equally true whether the disrupting force is due to a moment about the joint or to an in-line force applied during driving. The Gillen technique may be expected to “drive off” the lower pile from time to time during routine pile driving, and to buckle the joint if a more resistive formation such as sand should be encountered.
Swedish Patent 85,932 discloses the use of a suitable number of randomly placed flat bars or straps over the joint between two pilings secured by nails. An internal dowel pin, comprising a central collar portion and a tapered pin portion protruding into each end of the pilings, is apparently relied upon for rigidity. The flat bars are intended to prevent the joint from being pulled apart, but they would not be expected to be able to resist any but small bending moments.
U.S. Pat. No. 4,696,605, “Composite Reinforced Concrete And Timber Pile Section And Method Of Installation”, also to Gillen, employs a means of connecting which apparently relies upon the rigidity of the concrete pile itself to maintain a rigid joint. While technically sound, such a method may often be economically impractical.
U.S. Pat. No. 3,266,255, “Drive-Fit Transition Sleeve”, to Dougherty, employs a pair of flanged pipes telescoped one inside the other and force fitted to each other, much like a plug-and-socket arrangement. Dougherty, however, is obviously limited to connecting metal pilings, and calls for connecting the separate pieces of his connectors to the pilings by welding.
SUMMARY OF THE INVENTION
The present invention involves an improved piling connector which can transfer a bending moment and direct forces across a joint of a composite pile and a unique method of driving composite piles. Unlike pin-type connectors, or connectors which function essentially like a pin-type connector, the connector of the present invention will not allow one pile of a composite pile system to rotate with respect to the other or to induce an eccentricity into the overall, combined column. Further, a lower pile of this system may not be “driven off” the joint while driving the pile assembly, and the connector may be chosen such that it will not be the weakest link in the assembly. Still further, no special preparation or sizing of the ends of the pilings must be done in order to employ the present invention.
A preferred embodiment of the improved connector of the present invention comprises two rigid tubular members joined by a rigid ring or plate with at least one opening permitting fluid communication between the tubular members. Each tubular member preferably has a plurality of holes in the wall thereof, spaced apart both circumferentially and longitudinally, with a deflector attached to the outer wall in alignment with and spaced apart from each hole. When employing one preferred method, a pile is driven in the customary manner until the upper end is at a convenient height above ground level. The battered end is sawn off, as is customary when driving wooden piles. An open end of the connector is then placed on the upper end of the piling, and is rapidly driven onto the piling by the driver hammer. Outer portions of the piling are peeled off by the connector as it is being driven onto the piling, and such peelings are deflected away from the holes in the wall of the connector by the deflectors. The connection is then made rigid, preferably by screwing lag screws, of a size sufficient to permit the transfer of forces between piling and connector, through the wall openings and into the piling. An end of the second piling is then positioned above the upper end of the connector, and that piling is driven into the connector and similarly made rigid, at which point the driving of the composite pile assembly may recommence. If desired, the lag screws may be inserted into both ends of the connector simultaneously.
It is to be noted that no preparatory work has to be done on the piling ends to prepare them for insertion into the connector. Rather, the chambers of the connector are selected so as to accomodate the particular piling ends. While it is preferable to size such chambers so that no voids will exist between the connector walls and the piling, it is not essential to do so inasmuch as the lag screws may be installed in such a manner as to resist bending moments also.
Piling systems of the type contemplated herein are also capable of resisting considerable forces in tension.
A variation of this technique has been found preferable for joining wooden and metal pilings, as in the repair of existing foundations where space for working is extremely limited. This techique is often useful where too few pilings have been employed, where too short pilings have been employed, or where the upper ends of the pilings have dry rotted or are not connected to the foundation they were intended to support. In a preferred application of this technique, a small excavation is made to expose the upper end of the piling to be extended or repaired or to be connected to the foundation. The connector is then positioned on top of such piling and forced into snug engagement therewith, preferably by hydraulic ram. This portion of the connection may then be made rigid as described above. Short sections of wooden or metal pilings may then be employed, sequentially as necessary, until the desired depth is reached or the desired resistance is encountered If metal members have been used, they may be left in place as is, if desired, or a continuous concrete column may be created by pouring cement therein.
In still another variation, new pilings may be driven under an existing foundation by employing a succession of short pilings.
A BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the invention can be had when the detailed description of a preferred embodiment, set forth below, is considered in conjunction with the drawings, in which:
FIG. 1 is a sectional view of the connector of the present invention;
FIG. 2 is a plan view of such connector viewed from above;
FIG. 3 is an elevation view of a preferred method of the present invention illustrating the driving of the connector onto a first, unprepared piling end and the insertion of a first rigid connecting means, said connector being ready to receive the remainder of the rigid connecting means and then the upper piling;
FIG. 4 is an elevation view of a preferred method illustrating the driving of the upper wooden piling into the upper end of the connector of the present invention;
FIG. 5 is an elevation view of another preferred method illustrating the employment of the present invention with a metal piling;
FIG. 6 is an elevation view of said other preferred method illustrating said metal piling ready to receive the pouring of a continuous concrete column inside the shell of said metal piling;
FIG. 7 is a plan view of one such metal piling from an end thereof; and
FIG. 8 is a view of another specialized connector.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
It is to be understood that the following detailed description is of preferred embodiments only and is in no way limiting of the generality of the present invention.
FIGS. 1 and 2 illustrate a preferred connector of the present invention. FIGS. 3 and 4 illustrate preferred methods of employing such connector with various composite pile systems, while FIGS. 5 and 6 illustrate the use of a variant of such connector. FIG. 7 and 8 illustrate other preferred connectors.
The connector 10 of FIGS. 1 and 2 may be of any desired shape and size. While several different shapes have been found suitable, it has been found quite economical to fabricate the connector out of tubular members 11 and 12 and a flat plate 13 . It has also been found preferable to have the ends 14 and 15 of members 11 and 12 chamfered to permit easier “biting” when used with wooden pilings. Also, when used with wooden pilings, it has been found preferable in most circumstances to size the members 11 and 12 such that they are slightly smaller than the pilings to be connected, thereby automatically insuring a very tight fit regardless of variations in the pilings. It is to be understood that, if tubular, the diameter may be of whatever dimension is desired.
As may be seen from FIGS. 1 and 2, if a flat plate is used as the connecting element 13 , it is preferable to have at least one opening 16 to permit fluid communication between the interiors of members 11 and 12 . It has also been found preferable, when welding either member 11 or 12 to connecting element 13 , to do so in discontinuous welds 17 so that the fluid may escape from the interior of such members to the exterior. While deflectors 18 are not essential to the present invention, it is a time- and money-saving feature to have some means of deflecting the peelings 34 of the pilings away from wall openings 19 . With a connector so constructed, when using the system in the field one need not bother to cut away the peelings or otherwise bother with them in order to rapidly make the joint rigid.
Deflectors 18 may be of any convenient size and shape. It has been found quite convenient to employ short segments of “angle iron” or “flat bars” for this purpose, as they are easily welded to outer periphery members 11 and 12 .
FIG. 3 illustrates a step in the method of using the connector of the present invention with a wooden piling. If a new piling is being driven, the driving is stopped when the upper end of the piling is at a convenient work height. The connector 10 is then positioned on top of the piling, and at the desired angular orientation, and driven by the pile driver (not shown) onto the end of lower piling 31 . Deflectors 18 have deflected the outer or “excess” portions of piling 31 a distance away from openings 19 sufficient to permit ready access to openings 19 . As shown in FIG. 3, one rigid connector 32 has been inserted into piling 31 ; after all the rigid connections have been made, connector 10 is then ready to receive the upper piling.
If the upper piling 33 is also to be a wooden piling, it is then positioned and aligned as desired and driven into connector 10 as shown in FIG. 4, at which point it too is ready to be made rigid and then driven to the desired depth. Alternatively, all rigid connections may be made after connector 10 has received the upper piling.
If the upper piling is not to be a wooden piling—as frequently is the case when repairing existing construction—a metal piling or structural member 51 may be connected to connector 50 of FIG. 5 . Depending upon the application, one or a series of such members 51 may be employed and left in place, or a continuous concrete column may be created by pouring cement inside such member(s) 51 .
Structural members 51 may conveniently be comprised of short sections of pipe of any desired diameter. As shown in FIGS. 5-7, such segments may be rapidly connected in the tight space under an existing structure by previously welding a plurality of finger-like members 52 to the inside of such members 51 . As shown, the members 52 may be fastened to one end only of members 51 , or, if desired, they could be fastened to both ends of one member and alternated with a member having no members 52 . As shown in FIG. 7, the shape of such members 52 is immaterial, the only requirement being sufficient strength to resist any expected bending moments.
A safer structure will of course result if a continuous concrete column is created upon completion by pouring a cement mixture into the continuous cavity internal to the metal column 60 .
If an entirely new piling is to be constructed under an existing structure, it is convenient to begin by using as the first metal section a member 81 which is not open throughout its length. A most convenient structure is afforded by welding a solid plate 82 inside such member at a distance from the top sufficient to receive the finger-like members 52 . By having such plate spaced away from the bottom of such member, the member may easily penetrate the soil, initially, and become stabilized in direction, while simultaneously preventing the soil or mud from entering the full length of the column. Member 81 may in some circumstances be used in place of member 50 .
Other alternate forms of the present invention will suggest themselves from a consideration of the apparatus and practices hereinbefore discussed. Accordingly, it should be clearly understood that the systems and techniques depicted in the accompanying drawings, and described in the foregoing explanations, are intended as exemplary embodiments of the invention, and not as limitations thereto. | A method of rapidly installing a composite pile structure of timber pile sections and a pre-selected connector having an opening smaller than a transverse dimension of a working end of a timber pile section. The lower pile section is driven into the ground to a convenient distance, the connector is driven onto the lower pile and the upper pile driven onto the connector, and the connection is rapidly made rigid. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2007-314729 filed on Dec. 5, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND
1. Field
An aspect of the embodiments discussed herein is directed to a semiconductor device having a multilayer wiring structure and a method of manufacturing such a semiconductor device.
2. Description of the Related Art
Semiconductor integrated circuits manufactured today each contain vast numbers of semiconductor elements on the common board thereof and employ a multilayer wiring structure to connect such semiconductor elements with each other.
In a multilayer wiring structure, interlayer insulating films, in each of which wiring patterns are embedded to form a wiring layer, are laminated, and via contacts formed inside the interlayer insulating films connect the upper wiring layer and the lower wiring layer.
In particular, in current ultrafine and ultrahigh-speed semiconductor devices, low-dielectric-constant films (so-called low-k films) are used as such interlayer insulating films to reduce the problem of signal delay, for example RC delay, that occurs in a multilayer wiring structure, as well as low-resistance copper (Cu) patterns used as wiring patterns.
In this type of multilayer wiring structure, in which Cu wiring patterns are embedded in interlayer insulating films with a low dielectric constant, it is desirable to pattern the Cu layer by dry etching. A method often used to pattern the Cu layer by dry etching is a so-called damascene or dual damascene process, wherein wiring trenches or via holes are carved through interlayer insulating films in advance. These wiring trenches or via holes are filled with a Cu layer and then unnecessary portions of the Cu layer remaining on the interlayer insulating films are removed by chemical mechanical polishing (CMP).
Any direct contact of a Cu wiring pattern with an interlayer insulating film in this process would cause Cu atoms to diffuse into the interlayer insulating film, thereby leading to short circuits or other defects. These short circuits or other defects are generally avoided by covering the side walls and bottoms of wiring trenches or via holes used to form Cu wiring patterns with conductive diffusion barriers, also known as barrier metal films, and then coating the barrier metal films with a Cu layer. Examples of materials used for such a barrier metal film may include a high-melting-point metal such as tantalum (Ta), titanium (Ti), and tungsten (W) as well as conductive nitrides thereof.
However, in ultrafine and ultrahigh-speed semiconductor device based on current 45-nm technology or newer technologies, the size of wiring trenches or via holes carved through interlayer insulating films is significantly reduced along with miniaturization. To achieve desirable reduction in the resistance of wiring while using such a high-dielectric-constant barrier metal film, it is accordingly necessary that each of barrier metal films covering such ultrafine wiring trenches or via holes is as thin as possible while seamlessly covering the side walls and bottoms of the wiring trenches or via holes.
A technique that has been proposed to address this situation is direct covering of wiring trenches or via holes carved through interlayer insulating films with a copper-manganese alloy layer (Cu—Mn alloy layer). In this technique, Mn atoms contained in a Cu—Mn alloy layer react with Si and oxygen atoms contained in an interlayer insulating film and thus a manganese-silicon oxide layer having a thickness in the range of 2 nm to 3 nm and a composition of MnSi x O y is formed inside the Cu—Mn alloy layer as a diffusion barrier film.
However, it is known that in this technique the internally formed manganese-silicon oxide layer contains manganese (Mn) at a too low concentration and thus the adhesion of that layer to a Cu film is problematically weak.
Consequently, another structure of a barrier metal film in which a Cu—Mn alloy layer is combined with a barrier metal film based on a high-melting-point metal such as Ta or Ti has been proposed.
Such a barrier metal structure combining a Cu—Mn alloy layer with a barrier metal film based on a high-melting-point metal such as Ta or Ti provides preferable characteristics with improved resistance to oxidation through the sequence described below.
Recently, use of low-dielectric-constant porous films as a low-dielectric-constant material constituting interlayer insulating films has been proposed to prevent signal delay, for example RC delay. However, unfortunately, such a low-dielectric-constant porous material has a low density and thus is likely to be damaged by plasma during the manufacturing process, and a damaged film often retains moisture on the surface and inside thereof. Accordingly, a barrier metal film formed on such a low-dielectric-constant porous film would be likely to be oxidized by moisture retained inside and this often results in deteriorated characteristics of the barrier metal film and poor adhesion thereof to a Cu wiring layer or a via plug.
On the other hand, the Cu—Mn alloy layer described above contains Mn atoms, and if the layer is used as a seed layer, these Mn atoms react with oxidized portions of a barrier metal film, thereby ensuring characteristics of the barrier metal film necessary for its use as a diffusion barrier and maintaining high adhesion thereof to a Cu wiring layer or a via plug.
Related information may be found in the following patent documents:
Patent Document 1: Japanese Laid-open Patent Publication No. 2007-142236;
Patent Document 2: Japanese Laid-open Patent Publication No. 2005-277390.
SUMMARY
According to an aspect of an embodiment, a semiconductor device has a first insulating film formed over a semiconductor substrate, a first opening formed in the first insulating film, a first manganese oxide film formed along an inner wall of the first opening, a first copper wiring embedded in the first opening, and a second manganese oxide film formed on the first copper wiring containing carbon.
These together with other aspects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1F are diagrams for explanation of the conventional art;
FIG. 2 is a diagram for explanation of a problem in the conventional art;
FIGS. 3A-3F are diagrams for explanation of another conventional art;
FIG. 4 is a diagram illustrating a configuration of a semiconductor device according to Embodiment 1;
FIGS. 5A-5L are diagrams illustrating a manufacturing process of the semiconductor device according to Embodiment 1;
FIG. 6 is a diagram for explanation of reaction that occurs in a process according to Embodiment 1;
FIG. 7 is a diagram for explanation of the advantageous effect of Embodiments 1 and 2;
FIG. 8A is a diagram illustrating a configuration of a standard device tested as a control to demonstrate the advantageous effect of Embodiment 1;
FIG. 8B is a diagram illustrating a configuration of a device used to demonstrate the advantageous effect of Embodiment 1;
FIGS. 9A-9K are diagrams illustrating a manufacturing process of a semiconductor device according to Embodiment 2;
FIG. 10 is a diagram illustrating a configuration of a device used to demonstrate the advantageous effect of Embodiment 2;
FIG. 11 is an additional diagram demonstrating the advantageous effect of Embodiment 2; and
FIG. 12 is a diagram illustrating a configuration of a device used to demonstrate the advantageous effect of Embodiment 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1A to 1F are diagrams representing the process of forming a Cu wiring pattern.
In FIG. 1A , a silicon dioxide film 12 consisting of a methyl silsesquioxane (MSQ) film covers an insulating film 11 formed on a silicon substrate not shown in the drawing.
Then, as shown in FIG. 1B , a wiring trench 12 T corresponding to a desired wiring pattern is carved through the silicon dioxide film 12 .
After that, as shown in FIG. 1C , a barrier metal film 13 BM consisting of a high-melting-point metal, such as Ta, or a conductive nitride thereof, such as TaN, TiN, or WN, is formed so as to coat the top of the silicon dioxide film 12 and the side walls and bottom of the wiring trench 12 T.
In this structure shown in FIG. 1C , a Cu—Mn alloy layer 13 CM is also formed on the barrier metal film 13 BM so as to have the cross-sectional shape fitting the barrier metal film 13 BM.
Furthermore, a Cu layer 13 is formed on the Cu—Mn alloy layer 13 CM so as to fill the wiring trench 12 T as shown in FIG. 1C .
Then, CMP is applied to shave the Cu layer 13 , the Cu—Mn alloy layer 13 CM and the barrier metal film 13 BM existing therebeneath until the surface of the silicon dioxide film 12 is exposed. This step results in the structure shown in FIG. 1D , wherein the wiring trench 12 T is filled with a Cu wiring pattern 13 P.
After that, as shown in FIG. 1E , another silicon dioxide film 14 consisting of an MSQ film is formed on the structure shown in FIG. 1D , and the structure shown in FIG. 1E is then heated at a given temperature, for example, 400° C. to provide the structure shown in FIG. 1F . As a result, Ms atoms contained in the Cu—Mn alloy layer 13 CM are transported to the surface of the Cu wiring pattern 13 P, and the transported Mn atoms react with oxygen and Si atoms existing in the silicon dioxide film 14 , thereby forming a manganese oxide film 13 MOx having a composition of MnSi x O y on the surface of the Cu wiring pattern 13 P.
This process may exclude the use of a SiN film or other kinds of etching stopper films with a high dielectric constant, which is placed between the insulating films 12 and 14 in a known method, and is expected to further reduce the parasitic capacitance of the Cu wiring pattern 13 P.
It should be noted that the Cu—Mn alloy layer 13 CM existing between the Cu wiring pattern 13 P and the barrier metal film 13 BM releases Mn atoms and this transportation of Mn atoms completely blurs the boundary between the Cu—Mn alloy layer 13 CM and the Cu wiring pattern 13 P.
The wiring structure containing the Cu wiring pattern 13 P shown in FIG. 1F may have an insufficient performance of the manganese oxide film 13 MOx as a diffusion barrier. For example, Cu wiring patterns 13 P formed side-by-side as shown in FIG. 2 could possibly generate a potential difference between themselves so that Cu ions released from one Cu wiring pattern 13 P 1 would diffuse into the other Cu wiring pattern 13 P 2 , thereby leading to a short circuit.
However, surfaces of the Cu wiring patterns 13 P 1 and 13 P 2 other than the top surfaces are coated with a barrier metal film 13 BM and thus diffusion of Cu atoms therefrom may be prevented.
In addition, These discusses a technique to make up for the insufficient performance of the above-mentioned manganese oxide film 13 MOx as a diffusion barrier by covering the manganese oxide film 13 MOx with a barrier film such as a SiCN film as shown in FIGS. 3A to 3D . It should be noted that the components in FIGS. 3A to 3D that have already been described above are numbered with the reference numerals used in the previous explanation to avoid repetition.
The structure illustrated in FIG. 3A is equivalent to that shown in FIG. 1D and thus formed through the steps described by FIGS. 1A to 1C . In FIG. 3B , a silicon dioxide film 15 having a composition identical or similar to that of the silicon dioxide film 12 described earlier is formed on the structure shown in FIG. 3A . Then, this structure is heated at a temperature of approximately 400° C. to form a manganese oxide film 13 MOx covering the surface of the Cu wiring pattern 13 P described earlier in the same manner as shown in FIG. 1F .
After that, as shown in FIG. 3C , the silicon dioxide film 15 and a portion of the silicon dioxide film 12 lying therebeneath are removed by wet etching or plasma etching until the manganese oxide film 13 MOx is exposed.
In this step, it is difficult to stop the wet etching or plasma etching just at the time of the exposure of the manganese dioxide film 13 MOx. Exposing the entire surface of the manganese oxide film 13 MOx requires excessive etching. Therefore, in the structure shown in FIG. 3C , the upper part of the Cu wiring pattern 13 P supporting the manganese oxide film 13 MOx is also exposed so as to protrude from the insulating film 12 .
Then, as shown in FIG. 3D , a diffusion barrier film 16 consisting of a SiCN film is formed on the silicon dioxide film 12 so as to cover the protruding upper part of the Cu wiring pattern 13 P in FIG. 3C . Thereafter, the next insulating film 17 is formed on this diffusion barrier film 16 as shown in FIG. 3E .
It should be noted that the upper part of the Cu wiring pattern 13 P protrudes from the surface of the insulating film 12 as shown in FIG. 3D and accordingly the diffusion barrier film 16 has a protrusion 16 P. This causes the insulating film 17 to have a protrusion 17 P as shown in FIG. 3E .
After that, the damascene process is applied to the inside of the insulating film 17 in the same manner as described earlier to form a Cu wiring pattern 18 P that is supported by a barrier metal film 18 BM and is coated with a manganese oxide film 19 as shown in FIG. 3F .
However, in such a structure, each upper Cu wiring pattern 18 P extends so as to cross over the bumps made by the lower Cu wiring patterns 13 P. This makes it likely that the upper Cu wiring patterns 18 P and the lower Cu wiring patterns 13 P become short-circuited.
FIG. 4 is a diagram illustrating a configuration of a semiconductor device according to Embodiment 1, and FIGS. 5A to 5M and FIG. 6 are diagrams illustrating a manufacturing process of the semiconductor device.
In FIG. 4 , element regions 41 A and 41 B are defined on a silicon substrate 41 by element-isolating structures 41 I. On the element region 41 A, a gate insulating film 42 A is positioned on the silicon substrate 41 and a gate electrode 43 A made of polysilicon or the like is formed thereon, whereas on the element region 41 B, a gate insulating film 42 B is positioned on the silicon substrate 41 and a gate electrode 43 B made of polysilicon or the like is formed thereon.
The gate electrode 43 A has side walls coated with insulating films and, at both sides of this gate electrode 43 A, diffusion regions 41 a and 41 b are formed by ion implantation in the element region 41 A of the silicon substrate 41 . Similarly, the gate electrode 43 B also has side walls coated with insulating films and, at both sides of this gate electrode 43 B, diffusion regions 41 c and 41 d are formed by ion implantation in the element region 41 B of the silicon substrate 41 . As a result, transistors Tr 1 and Tr 2 are formed in the element regions 41 A and 41 B, respectively.
The gate electrodes 43 A and 43 B are covered with an insulating film 43 formed on the silicon substrate 41 , and a multilayer wiring structure 20 is formed on this insulating film 43 . This multilayer wiring structure 20 will be detailed below.
As shown in FIG. 4 , the multilayer wiring structure 20 has a so-called low-k interlayer insulating film 22 formed on the insulating film 43 . Examples of this low-k interlayer insulating film 22 may include an MSQ film with a dielectric constant of 2.6, a hydrocarbon polymer film such as SiLK or Porous SiLK (registered trademarks of The Dow Chemical Company), and a SiOC film produced by plasma chemical vapor deposition (CVD).
The interlayer insulating film 22 is coated with a carbon-including insulating film 24 that contains carbon (C) and silicon (Si), has a thickness in the range of 15 nm to 30 nm, and preferably consisting of a SiC film or a SiCN film. As described later, this carbon-including insulating film 24 further includes oxygen (O).
On the carbon-including insulating film 24 , a low-k interlayer insulating film equivalent to the above-mentioned low-k interlayer insulating film 22 is formed so as to have a thickness, for example, in the range of 250 nm to 300 nm. This low-k interlayer insulating film 25 is coated with a carbon (as well as silicon and oxygen)—including insulating film 27 that is equivalent to the above-mentioned carbon-including insulating film 24 and has a thickness in the range of 15 nm to nm.
Furthermore, on the carbon-including insulating film 27 , a low-k interlayer insulating film 28 equivalent to the above-mentioned low-k interlayer insulating films 22 and 25 is formed so as to have a thickness, for example, in the range of 250 nm to 300 nm. This low-k interlayer insulating film 28 is also coated with a carbon (as well as silicon and oxygen)—including insulating film 30 that is equivalent to the above-mentioned carbon-including insulating films 24 and 27 and has a thickness in the range of 15 nm to 30 nm.
Through the interlayer insulating film 22 , wiring trenches 22 T 1 and 22 T 2 are carved, which are filled with Cu wiring patterns 23 P and 23 Q, respectively. Side walls of these wiring trenches 22 T 1 and 22 T 2 are each coated with a barrier metal film 23 BM consisting of a high-melting-point metal such as Ta, Ti, or W, or a conductive nitride thereof such as TaN, TiN, or WN. Strictly speaking, the adjective “metal” may not be used to describe a barrier metal film 23 BM consisting of a conductive nitride. However, in the present embodiment, such a barrier film is also referred to as “a barrier metal film” in accordance with established practice. Meanwhile, the top of the Cu wiring pattern 23 P is covered with a manganese oxide film 23 MOx that includes carbon, has a composition of MnSi x O y C z (x=0.3 to 1.0; y=0.75 to 3.0; z=0.2 to 0.7), and formed along the carbon-including insulating film 24 so as to have a thickness approximately in the range of 1 nm to 5 nm. Such a manganese oxide film 23 MOx is also formed on the top of the Cu wiring pattern 23 Q. A more detailed description of this manganese oxide film 23 MOx will be provided later.
As described later, the boundary between the Cu wiring pattern 23 P and the barrier metal film 23 BM consists of a manganese oxide film 23 MOy formed so as to have a thickness in the range of 1 nm to 5-nm and a composition different from that of the manganese oxide film 23 MOx. This manganese oxide film 23 MOy includes no or little carbon and Si, and the concentrations of these elements included therein are substantially lower than those in the manganese oxide film 23 MOx, if any. For example, the manganese oxide film 23 MOy has a composition of MnO p C q (p=0.5 to 1.5; q=0.01 to 0.05; q<z).
Through the interlayer insulating film 25 , wiring trenches 25 T 1 , 25 T 2 , and 25 T 3 are carved, and these wiring trenches 25 T 1 , 2 ST 2 , and 2 ST 3 are filled with Cu wiring patterns 26 P, 26 Q, and 26 R, respectively. The lower part of the Cu wiring pattern 26 P forms a Cu via plug 26 V, which extends through the manganese oxide film 23 MOx to make an electrical contact with the Cu wiring pattern 23 P.
The side walls of the wiring trenches 25 T 1 , 25 T 2 , and 2 ST 3 are each coated with a barrier metal film 26 BM equivalent to the barrier metal film 23 BM. On the top of the Cu wiring pattern 26 P, a manganese oxide film 26 MOx equivalent to the manganese oxide film 23 MOx is formed along the carbon-including insulating film 27 so as to have a thickness approximately in the range of 1 nm to 5 nm. Such a manganese oxide film 26 MOx is also formed on the top of the Cu wiring patterns 26 Q and 26 R.
The boundary between the Cu wiring pattern 26 P and the barrier metal film 26 BM consists of a manganese oxide film 26 MOy that is equivalent to the manganese oxide film 23 MOy and formed so as to have a thickness in the range of 1 nm to 5 nm.
Through the interlayer insulating film 28 , wiring trenches 28 T 1 and 28 T 2 are carved, and these wiring trenches 28 T 1 and 28 T 2 are filled with Cu wiring patterns 29 P and 29 Q, respectively. The lower part of the Cu wiring pattern 29 P forms a Cu via plug 29 V, which extends through the manganese oxide film 26 MOx to make an electrical contact with the Cu wiring pattern 26 P.
The side walls of the wiring trenches 28 T 1 and 28 T 2 are each coated with a barrier metal film 29 BM equivalent to the barrier metal films 23 BM and 26 BM. On the top of the CU wiring pattern 29 P, a manganese oxide film 29 MOx equivalent to the manganese oxide films 23 MOx and 26 MOx is formed along the carbon-including insulating film 30 so as to have a thickness approximately in the range of 1 nm to 5 nm. Such a manganese oxide film 29 MOx is also formed on the top of the Cu wiring pattern 29 Q.
The boundary between the Cu wiring pattern 29 P and the barrier metal film 29 BM consists of a manganese oxide film 29 MOy that is equivalent to the manganese oxide films 23 MOy and 26 MOy and formed so as to have a thickness in the range of 1 nm to 5 nm.
In a semiconductor device 40 having the multilayer wiring structure 20 configured as above, each of the insulating films 23 MOx, 26 MOx, and 29 MOx formed on the Cu wiring patterns 23 P and 23 Q, 26 P to 26 R, and 29 P and 29 Q, respectively, includes a substantial amount of carbon as described above, and this reduces interatomic distances inside the films, thereby providing stronger chemical bonds. As a result, these insulating films act as excellent diffusion barriers and effectively prevent diffusion of Cu atoms constituting wiring patterns into low-dielectric-constant interlayer insulating films, thereby avoiding short circuits and other defects.
Next, a manufacturing process of the semiconductor device 40 , in particular, a process of forming the multilayer wiring structure, is described with reference to FIGS. 5A to 5L and FIG. 6 .
In FIG. 5A , the insulating film 43 is formed on the silicon substrate 41 so as to cover the transistors Tr 1 and Tr 2 , and then the interlayer insulating film 22 is formed on the insulating film 43 . Examples of this interlayer insulating film 22 may include an MSQ film or other SiO 2 -based low-dielectric-constant films formed by a coating method, a hydrocarbon polymer film such as SiLK or Porous SiLK (registered trademarks of The Dow Chemical Company), and a SiOC film produced by plasma CVD.
In the next step, the wiring trench 22 T 1 is carved through the interlayer insulating film 22 as shown in FIG. 5B . Although not shown in the drawing, the wiring trench 22 T 2 is also carved through the interlayer insulating film 22 .
Then, as shown in FIG. 5C , the barrier metal film 23 BM is formed on the interlayer insulating film 22 by sputtering of a Ta film, Ti film, or W film at room temperature so as to have the cross-sectional shape fitting the wiring trench 22 T 1 and have a thickness in the range of 2 nm to 5 nm. To form this barrier metal film 23 BM, reactive sputtering of a conductive nitride film such as a TaN film, TiN film, or WN film under nitrogen atmosphere may be used. The temperature of the substrate required for sputtering is approximately 400° C. Although not shown in the drawing, such a barrier metal film 23 BM is also formed on the wiring trench 22 T 2 .
In the step shown in FIG. 5C , a Cu—Mn alloy layer 23 CM is also formed on the barrier metal film 23 BM by sputtering of Cu—Mn alloy at room temperature. This Cu—Mn alloy layer 23 CM includes Mn atoms at a concentration in the range of 0.2 to 1.0 atomic percent or preferably at a concentration equal to or less than 0.5 atomic percent, has the cross-sectional shape fitting the wiring trench 22 T 1 , and has a thickness in the range of 5 nm to 30 nm. Although not shown in the drawing, such a Cu—Mn alloy layer 23 CM is also formed on the wiring trench 22 T 2 .
FIG. 5C also includes a Cu layer 23 , which is formed on the Cu—Mn alloy layer 23 CM by seed layer formation and electrolytic plating so as to fill the wiring trench 22 T 1 and, although not shown in the drawing, the wiring trench 22 T 2 as well.
Thereafter, as shown in FIG. 5D , the Cu layer 23 , and the Cu—Mn alloy layer 23 CM and the barrier metal films 23 BM formed therebeneath are shaved by CMP until the surface of the interlayer insulating film 22 is exposed. This results in the formation of the Cu wiring pattern 23 P in the wiring trench 22 T 1 and, although not shown in the drawing, the Cu wiring pattern 23 Q in the wiring trench 22 T 2 .
In this embodiment, the structure obtained in FIG. 5D is then coated with the carbon-including insulating film 24 having a thickness in the range of 15 nm to 30 nm as shown in FIG. 5E . The carbon-including insulating film 24 used in this embodiment is a SiCN film, which is formed by plasma CVD of a material including Si and C such as trimethylsilane (SiH(CH 3 ) 3 ) and a different material including nitrogen such as NH 3 with the substrate temperature being, for example, in the range of 350 to 400° C. Oxygen is added in the course of forming the carbon-including insulating film 24 so that the entire film includes oxygen at a concentration in the range of 3 to 18 atomic percent.
During this step shown in FIG. 5E , heat generated by the formation of the carbon-including insulating film 24 transports Mn atoms existing in the Cu—Mn alloy layer 23 CM to the surface of the Cu wiring pattern 23 P as shown in FIG. 6 . The transported Mn atoms react with Si, carbon, and oxygen atoms supplied by the carbon-including insulating film 24 . As a result, a manganese oxide film 23 MOx is formed on the surface of the Cu wiring pattern 23 P while spreading along the carbon-including insulating film 24 . The manganese oxide film 23 MOx formed in this way has a composition of MnSi x O y C z including composition parameters x, y, and z.
A manganese oxide film 23 MOx was actually prepared in the same way and analyzed by energy dispersive X-ray spectroscopy (EDX). This analysis found that the composition parameter x was in the range of 0.3 to 1.0, y was in the range of 0.75 to 3.0, and z was in the range of 0.2 to 0.7. Furthermore, secondary ion mass spectroscopy (SIMS) of a sample structure wherein a flat Cu—Mn film was coated with a Cu film and the Cu film was then coated with a SiCN film and the entire structure was heated at a temperature of 400° C. also demonstrated that this method, wherein a SiCN film is formed in contact with a Cu—Mn film, may be used to provide a manganese oxide film that has a composition of MnSi x O y C z and spreads between the SiCN and Cu—Mn films.
The step represented by FIG. 5E also involves transportation of a small number of oxygen atoms from the interlayer insulating film 22 through the barrier metal film 23 BM to the Cu wiring pattern 23 P during heat treatment associated with the formation of the carbon-including insulating film 24 . As shown in FIG. 6 , such oxygen atoms react with some of Mn atoms initially included in the Cu—Mn alloy layer 23 CM, thereby producing another manganese oxide film 23 MOy between the barrier metal film 23 BM and the Cu wiring pattern 23 P. This manganese oxide film 23 MOy includes no or little carbon and Si, and the concentrations of these elements included therein are lower than those in the manganese oxide film 23 MOx, if any. Therefore, the manganese oxide film 23 MOy produced in this way has a composition of MnO p C q wherein the composition parameter p is in the range of 0.5 to 1.5 and q is in the range of 0.01 to 0.05, as described earlier. It should be noted that q is smaller than z.
The original Cu—Mn alloy layer 23 CM is reduced as such manganese oxide films 23 MOx and 23 MOy are formed and finally disappears at the end of the step represented by FIG. 5E due to replacement with a Cu layer serving as a part of the Cu wiring pattern 23 P.
In the next step shown in FIG. 5F , the structure illustrated by FIG. 5E is covered with the interlayer insulating film 25 formed in the same manner as the interlayer insulating film 22 . After that, as shown in FIG. 5G , a wiring trench 2 ST 1 and a via hole 25 V 1 are carved in preparation for the formation of the Cu wiring pattern 26 P, and this exposes the Cu wiring pattern 23 P under the wiring trench 25 T 1 and the via hole 25 V 1 . At the same time, the wiring trenches 25 T 2 and 25 T 3 are carved through the interlayer insulating film 25 in preparation for the formation of the Cu wiring patterns 26 Q and 26 R, respectively.
Then, as shown in FIG. 5H , the barrier metal film 26 BM is formed on the interlayer insulating film 25 , which is illustrated in FIG. 5G , by sputtering of a Ta film, Ti film, or W film at room temperature so as to have the cross-sectional shape fitting the wiring trench 25 T 1 and has a thickness in the range of 2 nm to 5 nm. To form this barrier metal film 26 BM, reactive sputtering of a conductive nitride film such as a TaN film, TiN film, or WN film under nitrogen atmosphere may be used. The temperature of the substrate required for sputtering is approximately 400° C. Although not shown in the drawing, such a barrier metal film 26 BM is also formed on the wiring trenches 25 T 2 and 25 T 3 .
In the step shown in FIG. 5H , a Cu—Mn alloy layer 26 CM is also formed on the barrier metal film 26 BM by sputtering of Cu—Mn alloy at room temperature. This Cu—Mn alloy layer 26 CM includes Mn atoms at a concentration in the range of 0.2 to 1.0 atomic percent, has the cross-sectional shape fitting the wiring trench 25 T 1 , and has a thickness in the range of 5 nm to 30 nm. Although not shown in the drawing, such a Cu—Mn alloy layer 26 CM is also formed on the wiring trenches 25 T 2 and 25 T 3 .
FIG. 5H also includes a Cu layer 26 , which is formed on the Cu—Mn alloy layer 26 CM by seed layer formation and electrolytic plating so as to fill the wiring trench 25 T 1 and, although not shown in the drawing, the wiring trenches 25 T 2 and 25 T 3 as well.
Thereafter, as shown in FIG. 5I , the Cu layer 26 , and the Cu—Mn alloy layer 26 CM and the barrier metal film 26 BM formed therebeneath are shaved by CMP until the surface of the interlayer insulating film 25 is exposed. This results in the formation of the Cu wiring pattern 26 P in the wiring trench 25 T 1 and, although not shown in the drawing, the Cu wiring patterns 26 Q and 26 R in the wiring trenches 25 T 2 and 25 T 3 , respectively.
In this embodiment, the structure obtained in FIG. 5I is then coated with the carbon-including insulating film 27 having a thickness in the range of 15 nm to 30 nm as shown in FIG. 53 . The carbon-including insulating film 27 used in this embodiment is a SiCN film, which is formed by plasma CVD of a material including Si and C such as trimethylsilane (SiH(CH 3 ) 3 ) and a different material including nitrogen such as NH 3 with the substrate temperature being, for example, in the range of 350 to 400° C. Oxygen is added in the course of forming the carbon-including insulating film 27 so that the entire film includes oxygen at a concentration in the range of 3 to 18 atomic percent.
During this step shown in FIG. 53 , heat generated by the formation of the carbon-including insulating film 27 transports Mn atoms existing in the Cu—Mn alloy layer 26 CM to the surface of the Cu wiring pattern 26 P as described earlier using FIG. 6 . The transported Mn atoms react with Si, carbon, and oxygen atoms supplied by the carbon-including insulating film 27 . As a result, a manganese oxide film 26 MOx having a composition of MnSi x O y C z is formed on the surface of the Cu wiring pattern 26 P while spreading along the carbon-including insulating film 27 , in the same manner as the manganese oxide film 23 MOx.
The step represented by FIG. 5J also involves transportation of a small number of oxygen atoms from the interlayer insulating film 25 through the barrier metal film 26 BM to the Cu wiring pattern 26 P during heat treatment associated with the formation of the carbon-including insulating film 27 . As described earlier using FIG. 6 , such oxygen atoms react with some of Mn atoms initially included in the Cu—Mn alloy layer 26 CM, thereby producing another manganese oxide film 26 MOy between the barrier metal film 26 BM and the Cu wiring pattern 26 P (via plug 26 V) in the same manner as the manganese oxide film 23 MOy. This manganese oxide film 26 MOy includes no or little carbon and Si, and the concentrations of these elements included therein are lower than those in the manganese oxide film 26 MOx, if any.
Also in this case, the original Cu—Mn alloy layer 26 CM is reduced as such manganese oxide films 26 MOx and 26 MOy are formed and finally disappears at the end of the step represented by FIG. 53 .
In the next step shown in FIG. 5K , the structure illustrated by FIG. 53 is covered with the interlayer insulating film 28 formed in the same manner as the interlayer insulating films 22 and 25 . Then, the steps shown in FIGS. 5G to 51 are repeated to carve the wiring trench 28 T 1 through the interlayer insulating film 28 , to cover the wiring trench 28 T 1 with the barrier metal film 29 BM, and then to fill the wiring trench 28 T 1 with the Cu wiring pattern 29 P. After that, in the upper part of the Cu wiring pattern 29 P, the manganese oxide film 29 MOx is formed in the same manner as the manganese oxide films 23 MOx and 26 MOx along a carbon-including insulating film 30 formed as with the carbon-including insulating film 27 . In the boundary between the Cu wiring pattern 29 P and the barrier metal film 29 BM, the manganese oxide film 29 MOy is formed in the same manner as the manganese oxide films 23 MOy and 26 MOy.
FIG. 7 shows the result of a time-dependent dielectric breakdown test (TDDB test) conducted using a semiconductor device 40 having the multilayer wiring structure 20 configured as above.
In FIG. 7 , “(d) CONVENTIONAL ART” indicates the result obtained using a standard device that was tested as a control of the present embodiment and corresponds to the structure described earlier using FIG. 2 . This standard device was configured as follows: the Cu wiring patterns 13 P each having a width of 70 nm were arranged at intervals of 70 nm; the barrier metal film 13 BM had a thickness of 2 nm; and the manganese oxide film 13 MOx had a thickness of 20 nm and a composition of MnSi x O y wherein the composition parameter x is 0.3 and y is 0.5.
“(c) WITHOUT Mn” in FIG. 7 indicates the result obtained using another standard device tested as a control, which was prepared excluding the formation of the Cu—Mn alloy layer 23 CM in the steps shown in FIGS. 5A to 5E and thus had no manganese oxide film 23 MOx on the top of Cu wiring patterns 23 P 1 and 23 P 2 as shown in FIG. 8A . In this standard device, the formation of the manganese oxide films 23 MOy, which would have been formed on the side walls and the bottom of the Cu patterns, was accordingly omitted. It should be noted that the components in FIG. 8A that have already been described above are numbered with the reference numerals used in the previous explanation to avoid repetition. For comparison, this standard device included the interlayer insulating films 22 and 25 having the same composition and the same thickness as those of the interlayer insulating films 12 and 14 shown in FIG. 2 as well as a barrier metal film 23 BM having the same composition and the same thickness as the barrier metal film 13 BM shown in FIG. 2 . The width and intervals of the Cu wiring patterns 23 P 1 and 23 P 2 were the same as those used in the standard device illustrated in FIG. 2 .
“(a) EMBODIMENT 1” in FIG. 7 indicates the result obtained using the device that corresponds to Embodiment 1 described earlier and thus Cu wiring patterns 23 P 1 and 23 P 2 thereof were formed in the steps described using FIGS. 5A to 5F , as illustrated in FIG. 8B . It should be noted that the components in FIG. 8B that have already been described above are numbered with the reference numerals used in the previous explanation to avoid repetition. For comparison, this device included the interlayer insulating films 22 and 25 having the same composition and the same thickness as those of the interlayer insulating films 12 and 14 shown in FIG. 2 as well as a barrier metal film 23 BM having the same composition and the same thickness as the barrier metal film 13 BM shown in FIG. 2 . The width and interval of the Cu wiring patterns 23 P 1 and 23 P 2 were the same as those used in the standard device illustrated in FIG. 2 .
“(b) EMBODIMENT 2” in FIG. 7 indicates the result obtained using Embodiment 2, which will be described later.
In this test summarized in FIG. 7 , a voltage of 30 V was applied between adjacent Cu wiring patterns of each device at a temperature of 150° C. and the time to dielectric breakdown was measured.
The TDDB values on the vertical axis of FIG. 7 have been normalized with respect to the value for the standard device shown in “(d) CONVENTIONAL ART.” As is obvious from the graph, the TDDB value of the other standard device shown on “(c) WITHOUT Mn” is almost equal to that shown in “(d) CONVENTIONAL ART.” This means that the carbon-including film 24 itself has little or no ability to prevent diffusion of Cu atoms.
On the other hand, the TDDB value of the device corresponding to Embodiment 1 and shown in “(a) EMBODIMENT 1” is more than 12 times higher than that of the standard device tested as a control.
Therefore, it may be said that, among others, the manganese oxide film 23 MOx including carbon exhibits especially high performance in preventing diffusion of Cu atoms and that the semiconductor device 40 configured according to Embodiment 1 so as to have such a manganese oxide film 23 MOx and the equivalents thereof, i.e., manganese oxide films 26 MOx and 29 MOx, acquires a long service life.
FIGS. 9A to 9K are diagrams illustrating a manufacturing process of a semiconductor device according to Embodiment 2. It should be noted that the components in FIGS. 9A to 9K that have already been described above are numbered with the reference numerals used in the previous explanation to avoid repetition.
FIG. 9A corresponds to the structure shown in FIG. 5D with the exception that the interlayer insulating film 22 is a low-dielectric-constant SiO 2 film resistant to etching of a hydrocarbon polymer film, such as an MSQ film.
In Embodiment 2, as shown in FIG. 9B , a carbon-including film 31 is formed on the structure illustrated by FIG. 9A so as to cover the top of the interlayer insulating film 22 and that of the Cu wiring pattern 23 P. This carbon-including film 31 is, for example, a hydrocarbon polymer film commercially available under the name of SiLK (registered trademarks of The Dow Chemical Company) or a similar film that includes carbon (C) and oxygen, is resistant to heat treatment at a temperature in the range of 350 to 400° C., and allows selective etching of the interlayer insulating film 22 existing therebeneath.
Then, the structure shown in FIG. 9B is heated at a temperature in the range of 350 to 400° C. under inert atmosphere or, more typically, nitrogen atmosphere. Thereafter, a manganese oxide film 33 MOx whose composition is represented using composition parameters s and t (MnO s C t ) is formed so as to cover the top of the Cu wiring pattern 23 P while spreading along the hydrocarbon polymer film 31 . More specifically, the manganese oxide film 33 MOx is formed from Mn atoms initially included in the Cu—Mn alloy layer 23 CM and oxygen and carbon atoms supplied by the hydrocarbon polymer film 31 through the reaction thereof so as to have a thickness in the range of 1 nm to 5 nm. The composition parameters s and t of the manganese oxide film 33 MOx formed in this way are 0.75 to 3.0 and 0.2 to 0.7, respectively.
Furthermore, oxygen atoms that are released from the interlayer insulating film 22 penetrate through the barrier metal film 23 BM into the Cu wiring pattern 23 P and then react with Mn atoms existing in the Cu—Mn alloy layer 23 CM, thereby producing a manganese oxide film 33 MOy spreading between the Cu wiring pattern 23 P and the barrier metal film 23 BM. This manganese oxide film 33 MOy has a composition represented using composition parameters u and v (MnO u C v ) wherein the composition parameter v is zero or any number less than t (v<t).
Embodiment 2 further involves the step shown in FIG. 9D , wherein the carbon-including film 31 was removed through the process of selective etching or ashing so as to expose the interlayer insulating film 22 and the manganese oxide film 33 MOx preferentially.
Subsequently, as shown in FIG. 9E , the structure illustrated by FIG. 9D is covered with the next interlayer insulating film 25 consisting of an MSQ film or a similar silicon oxide film. After that, a wiring trench 25 T 1 and a via hole 25 V 1 are carved through the interlayer insulating film 25 so that the Cu wiring pattern 23 P is exposed, as shown in FIG. 9F .
Furthermore, as shown in FIG. 9G , the interlayer insulating film 25 seen in FIG. 9F is coated with the barrier metal film 26 BM and then with the Cu—Mn alloy film 26 CM in the same manner as the step described using FIG. 5H so that the coating layers have the cross-sectional shape fitting the wiring trench 2 ST 1 .
FIG. 9G also includes a Cu layer 26 , which is formed on the Cu—Mn alloy layer 26 CM by seed layer formation and electrolytic plating so as to fill the wiring trench 25 T 1 and the via hole 25 V 1 .
Thereafter, as shown in FIG. 9H , the Cu layer 26 , and the Cu—Mn alloy layer 26 CM and the barrier metal layer 26 BM formed therebeneath are shaved by CMP until the surface of the interlayer insulating film 25 is exposed. This results in the formation of the Cu wiring pattern 26 P in the wiring trench 25 T 1 and, although not shown in the drawing, the Cu wiring patterns 26 Q and 26 R in the wiring trenches 25 T 2 and 25 T 3 , respectively.
In this embodiment, the structure obtained in FIG. 9H is then coated with the carbon-including film 32 having the same composition as the carbon-including film 31 and a thickness in the range of 15 nm to 30 nm as shown in FIG. 9I , and then this structure is heated at a temperature in the range of 350 to 400° C. This heat treatment makes Mn atoms existing in the Cu—Mn alloy layer 26 CM move to the surface of the Cu wiring pattern 26 P and react with carbon and oxygen atoms supplied by the carbon-including film 32 there as described earlier using FIG. 6 . As a result, a manganese oxide film 36 MOx having a composition of MnO s C t described earlier is formed on the surface of the Cu wiring pattern 26 P while spreading along the carbon-including film 32 , in the same manner as the manganese oxide film 33 MOx.
The step represented by FIG. 9I also involves transportation of a small number of oxygen atoms from the interlayer insulating film 25 through the barrier metal film 26 BM to the Cu wiring pattern 26 P during the heat treatment. As described earlier using FIG. 6 , such oxygen atoms react with some of Mn atoms initially included in the Cu—Mn alloy layer 26 CM, thereby producing another manganese oxide film 36 MOy between the barrier metal film 26 BM and the Cu wiring pattern 26 P (via plug 26 V) in the same manner as the manganese oxide film 33 MOy. This manganese oxide film 36 MOy includes no carbon or carbon at any concentration lower than that in the manganese oxide film 36 MOx.
Also in this case, the original Cu—Mn alloy layer 26 CM is reduced as such manganese oxide films 36 MOx and 36 MOy are formed and finally disappears at the end of the step represented by FIG. 9I .
In the next step shown in FIG. 9J , the structure illustrated by FIG. 9I is covered with the interlayer insulating film 28 formed in the same manner as the interlayer insulating films 22 and 25 . Then, the steps shown in FIGS. 9E to 9I are repeated to carve the wiring trench 28 T 1 through the interlayer insulating film 28 , to cover the wiring trench 28 T 1 with the barrier metal film 29 BM, and then to fill the wiring trench 28 T 1 with the Cu wiring pattern 29 P. After that, in the upper part of the Cu wiring pattern 29 P, an additional carbon-including insulating film is formed in the same manner as the carbon-including film 30 , and the manganese oxide film 39 MOx is formed in the same manner as the manganese oxide films 33 MOx and 36 MOx along the additional carbon-including film. Between the Cu wiring pattern 29 P and the barrier metal film 29 BM, the manganese oxide film 39 MOy is formed in the same manner as the manganese oxide films 33 MOy and 36 MOy. It should be noted that FIG. 9K represents the structure obtained by removing the additional carbon-including insulating film after the process described above.
The result of the TDDB test conducted using the multilayer wiring structure prepared in accordance with Embodiment 2 is also shown in FIG. 7 as “(b) EMBODIMENT 2.” This test involved a semiconductor device equivalent to that shown in FIG. 8B with exceptions that the interlayer insulating film 25 was formed directly on the interlayer insulating film 22 and that the manganese oxide films 33 MOx and 33 MOy were used instead of the manganese oxide films 23 MOx and 23 MOy as shown in FIG. 10 . This device also employed an interval of 70 nm between adjacent Cu wiring patterns as well as the other tested devices.
As clearly seen in FIG. 7 , the TDDB value of the device corresponding to Embodiment 2 is also more than 12 times higher than that of the standard device tested as a control.
Meanwhile, FIG. 11 represents the result of short-circuit study, wherein a test structure in which upper Cu wiring patterns 18 P extend while crossing over the lower Cu wiring patterns 13 P, like one described earlier using FIG. 3F , was prepared through the steps shown in FIGS. 9A to 9K and then occurrences of short circuits between the upper and lower Cu wiring patterns were monitored. As shown in FIG. 12 , this test structure includes the lower Cu wiring patterns 13 P and the upper Cu wiring patterns 18 P arranged so as to be perpendicular to each other, and the interval between adjacent Cu wiring patterns was set at 70 nm for both upper and lower patterns. In addition, the structure used in this test was configured without the via plugs 26 V and 29 V.
As seen in FIG. 11 , the occurrence rate of short circuits was approximately in the range of 2 to 3% in the semiconductor device prepared in accordance with Embodiment 2, whereas the occurrence rate of short circuits was higher than 85% in the standard device as a control prepared in the steps shown in FIGS. 3A to 3F . In this standard device prepared in the steps shown in FIGS. 3A to 3F , the diffusion barrier film 16 had a bump with a height of 30 nm due to the Cu wiring pattern 13 P and the height of the interlayer insulating film 17 was 300 nm.
The result shown in FIG. 11 probably reflects the fact that the present embodiment employs a lower interlayer insulating film 22 and a manganese oxide film 33 MOx both resistant to etching and thus no bump is formed after the hydrocarbon polymer film 31 is removed by dry etching or ashing in the step shown in FIG. 9D .
Meanwhile, in the present embodiment, the interlayer insulating films 22 , 25 , and 28 do not always have to consist of an MSQ film. Although having a higher dielectric constant, a silicon oxide film produced by plasma CVD of tetraethoxysilane (TEOS) may also be used depending on the intended application.
The many features and advantages of the embodiments are apparent from the detailed specification and, thus, it is intended by the appended claims to cover all such features and advantages of the embodiments that fall within the true spirit and scope thereof. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the inventive embodiments to the exact construction and operation illustrated and described, and accordingly all suitable modification and equivalents may be resorted to, falling within the scope thereof. | A semiconductor device has a first insulating film formed over a semiconductor substrate, a first opening formed in the first insulating film, a first manganese oxide film formed along an inner wall of the first opening, a first copper wiring embedded in the first opening, and a second manganese oxide film formed on the first copper wiring including carbon. | 7 |
FIELD OF THE INVENTION
The present invention relates to N-terminally modified linear and branched polyamine conjugated peptidomimetics as antimicrobials agents. Particularly, the invention relates to compositions comprising N-terminal modified linear/branched peptidomimetics conjugated with polyamines for treatment of infections caused by planktonic/biofilm embedded bacteria including multidrug resistant pathogens in human or animals.
BACKGROUND AND PRIOR ART OF THE INVENTION
The reference may be made to Nat. Rev. Drug Discov., 6:943-944, 2007 discloses antibiotic resistance is a major global health care concern due to infections related to the escalating multiple drug resistant (MDR) pathogens.
The reference may be made to N. Engl. J. Med. 360:439-443, 2009 and Nature, 499:394- 396, 2013 disclose MDR strains of methicillin resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterrococci (VRE) and carbapenem-resistant Enterobacteriaceae (CREs) in communities and nosocomial environments are rendering antibiotic therapy more difficult and costly at an unprecedented rate.
The reference may be made to Nat. Rev. Microbiol, 2:95-108, 2004 and Chem. Biol., 19:1503-1513, 2012 disclose the development of resistance is aggravated by irrational use of antibiotics in livestock and healthcare practices that has armed microbes with multitude of novel drug resistance mechanisms. Microbes are among the most successful organisms owning to their rapid regeneration time which allows accumulation of resistance conferring genes through antibiotic stress or through exchange of plasmids with other microbes. Additionally a passive, known contributory life style approach towards resistance development in microbes is biofilm formation. Through a network of chemical signals (quorum sensing agents) biofilms nurture slow growing and heterogeneous microbial populations that differ among themselves phenotypically as well as genetically.
The reference may be made to Nat. Rev. Microbiol., 8:623-633, 2010 discloses biofilms are matrix associated microbial communities adhered to surfaces or floating at air-water inter-phase where, the microbes are embedded in a self-produced exopolymeric substance (EPS). The biofilm matrix mostly comprises of proteins, extra cellular DNA with different extracellular polysaccharides.
The reference may be made to Int. J. Antimicrob. Agents., 35:322-332, 2010 discloses the biofilms play a major role in almost 80% infections, including cystic fibrosis, dental plaques, chronic wounds and implanted medical device infections.
The reference may be made to Trends Microbiol., 9:34-39, 2001 discloses most of the antibiotics target growth related metabolic processes in bacteria however, the heterogeneous population of actively dividing and persister microorganism in biofilms make them recalcitrant infection reservoirs which further contributes to virulence since the exopolymeric matrix and retarded metabolic activity inside biofilm communities leads to increased persistence of biofilms.
The reference may be made to Nature., 436:1171-1175, 2005 discloses the bacteria in biofilms generally tolerate antibiotic treatment, and antibiotics can even produce a trigger for biofilm formation.
The reference may be made to Nature, 415:389-395, 2002 and Nat. Rev. Microbiol., 3:238-250, 2005 describe, Host defense cationic peptides [HDCPs] (12-60 mer) and their mimics with several simultaneous target mechanisms in microbes are commercial candidates that hold potential to circumvent drug resistance MDR pathogens.
The reference may be made to Nat. Rev. Microbiol. 3:238-250, 2005 discloses HDCPs are evolutionary conserved and produced as a component of innate immunity by almost all living organisms as a first line of defense against invading microbes. Owing to global amphipathicity i.e. balance between positive charge at physiological pH and hydrophobicity, HDCPs predominantly exhibit membrane disruptive mode of action although they have also been reported as metabolic inhibitors in microbes.
The reference may be made to J. Appl. Microbiol., 104:1-13, 2008 describe the positive charge on HDCPs helps them to get attracted to negatively charged surface of bacterial cells, facilitating primary interactions. After initial attachment, by virtue of their amphipathic nature HDCPs are able to partition in bacterial membranes leading to transient or irreversible cellular content leakage which ultimately leads to bacterial cell death. Due to a rapid killing ability and simultaneous targeting of multiple organelles it is difficult for bacteria to develop resistance against HDCPs. HDCPs have also been reported to efficiently eradicate slow-growing cells from planktonic and biofilm cultures and thus have been proposed as promising alternative agents in the cure of biofilm associated MDR infections as well.
The reference may be made to Nat. Biotechnol, 17:755-757, 1999 describe the bottlenecks in the application of HDCPs have been their high cost, scalability, protease stability, reduced activity in presence of physiological salts concentrations and poor bioavailability.
The reference may be made to Antimicrob. Agents Chemother. 58: 5136-5145, 2014 and J. Appl. Microbiol, 110:229-238, 2011 and J. Antimicrob. Chemother. 64: 735-740, 2009 and J. Med. Chem. 54:786-5795, 2011 describe mimic HDCPs functions in miniature peptidomimetics has lead to discovery of potent molecules such as brilacidin, cationic steroid antibiotics (CSA), XF-73, and LTX-109 most of which are currently under clinical trials as antibacterial agents.
The reference may be made to Int. J. Biochem. Cell. Biol. 42:39-51, 2010 describes the polyamines (putrescine, spermidine, and spermine) are essential organic polycations that modulate cellular processes like nucleic acid packaging, DNA replication, transcription, and translation.
The reference may be made to Expert Rev. Mol. Med. 22:15:e3, 2013 and Bioorg. Med. Chem., 13:2523-2536 and Antimicrob. Agents Chemother., 50:852-861, 2006 describe the synthetic polyamine conjugates exhibit versatile biological activities, including anticancer, antiparasitic, antiendotoxin, and antibacterial activities.
The reference may be made to J. Appl. Microbiol., 110:229-238, 2011 and Bioorg. Med. Chem., 13:2523-2536, 2005 and Arch. Pharm. Res. 31:698-704, 2008 disclose the role of polyamine conjugation in improving activity for a number of synthetic antibacterial agents, such as ceragenins, acylpolyamines, and caffeoyl polyamines.
The reference may be made to Antimicrob. Agents Chemother., 51:2070-2077, 2007 describe the synergistic effect of exogenous polyamines and various antibiotics.
The reference may be made to Org Biomol Chem., 10:8326-8335, 2012 and Antimicrob Agents Chemother., 58:5435-5447, 2014 describe the ultra short di-peptidomimetics based on polyamine backbone that showed excellent anti methicillin resistant S. aureus (MRSA) activity in vitro against planktonic cells. Further, the designed di-peptidomimetics ( Org Biomol Chem., 10:8326-8335, 2012) were found equally or rather better active against methicillin resistant S. aureus as compared to S. aureus . Polyamines were initially thought to be ubiquitous and were expected to be present in mammals as well microbes, However, recently it was shown that S. aureus produces no spermine/spermidine or their precursors; therefore, polyamines and their conjugates act as toxins to S. aureus. [Mol. Microbiol. 82:9-20, 2011]
The reference may be made to Cell Host Microbe, 13:100-107, 2013 discloses Further, the exceptional virulence of MRSA strain USA300 was ascribed to development of resistance genes to spermidine and other polyamines.
Therefore, for polyamine-sensitive MRSA, conjugation of spermine is a robust strategy to overcome this deadly strain.
OBJECTIVE OF THE INVENTION
The main object of the present invention is to provide N-terminally modified linear and branched polyamine conjugated peptidomimetics as antimicrobials agents.
The other objective of the present invention is to provide the treatment of infections caused by planktonic/biofilm embedded bacteria including multidrug resistant pathogens in human or animals.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides N-terminally modified linear and branched polyamine conjugated peptidomimetics as antimicrobials agents.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 : Illustrates the design of polyamine conjugated peptidomimetics
FIG. 2 : Illustrates the concentration dependent cell membrane depolarization assessed by potential sensitive dye DiSC 3 (5) in intact S. aureus cells.
FIG. 3 : Illustrates bactericidal kinetic of designed peptidomimetics incubated with S. aureus ATCC 33591, where (A) Killing curve at 2×MIC and (B) Killing curve with 4×MIC of compounds 1c, 1d and Vancomycin (VAN) and sampled at the indicated time points.
FIG. 4 : Illustrates scanning electron microscopic images of MRSA. (A) Untreated bacterial cells, (B) cells treated with compound 1c, (C) cells treated with compound 1d and (D) cells treated with VAN. The cells were exposed to various agents for 30 min at 10× their respective planktonic MIC. The arrows point at morphological alterations caused. Higher magnification (150KX) images of each image have been given in inset.
FIG. 5 : Illustration of resistance development study in S. aureus (ATCC 33591) after 17 serial passages with sub MIC of 1c/1d or antibiotic treatment. The fold change in MIC is the ratio of the MIC after 17 passages relative to that MIC observed before first passage.
FIG. 6 : Illustration (A, B) is Inhibition of MRSA biofilm formation by different agents using alamar blue assay and biomass quantification using crystal violet staining assay, respectively. In (C), (D) is metabolic activity of 24 h mature biofilm embedded MRSA using alamar blue assay and biomass quantification using crystal violet, respectively. Where, MIC b is planktonic MIC in biofilm media for 1c, 1d and VAN was 7.1 μg/mL, 3.5 μg/mL and 0.8 μg/mL, respectively. For all experiments data is expressed as mean±SD. Statistical differences from the control were determined by one-way analysis of variance (ANOVA) with Tukey's multiple comparison post hoc tests. All differences between the control and treated biofilms were considered statistically significant (*P<0.001).
FIG. 7 : Illustrates 3D images of MRSA biofilm, A) Effect of antibacterial agents on biofilm formation of MRSA using confocal laser scanning microscopy. In a) Control, b) 1c (sub-MIC b ), c) 1c (MIC b ), d) 1d (sub-MIC b ), e) 1d (MIC b ), f) VAN (sub-MIC b ), and g) VAN (MIC b ). B) Effect of antibacterial agents against 24 h mature preformed MRSA biofilm using confocal laser scanning microscopy. In a) control, b) 1c (10×MIC b ), c) 1c (20×MIC b ), d) 1d (10×MIC b ), e) 1d (20×MIC b ), f) VAN (10×MIC b ), and g) VAN (20×MIC b ). After treatment at different concentrations the biofilms were stained with Syto9 (green; viable cells) and propidium iodide (red; dead cells) as described by manufacturers' protocol.
FIG. 8 : Serum stability assay of peptidomimetics at 37° C. using RP-HPLC.
DETAILED DESCRIPTION OF THE INVENTION
Based on the pharmacophore of short antimicrobial peptidomimetics, various structure-activity relationships have been reported, where modifications in charge distribution or hydrophobicity have led to optimization of molecules for therapeutic applications [ J. Med. Chem. 46:1567-1570, 2003 ; Biopolymers, 90:83-93, 2008]. In the present invention we report two series of peptidomimetics (Structure 1 and Structure 2) with linear/branched arrangements of Tryptophan (Trp) residues on the polyamine (spermidine/spermine) backbone to explore the effects on antibacterial activity and selectivity.
The general structure of template in present invention is represented by the following schematics:
wherein R can be hydrogen or any carboxylic acid moiety conjugated through amide bond (—CONH—), or ester bond (—COOR—) or 2-(4-(trifluoromethyl)phenyl) acetic acid, 2-(4-fluorophenyl)aceticacid, 4-(aminomethyl)benzoic acid, 4-(aminomethyl)benzoic acid, 3-(4-hydroxyphenyl)propanoic acid, 3-(3,4-dihydroxyphenyl)propanoic acid, 3-(3,4-dihydroxyphenyl)acrylic acid (Caffeic acid), (E)-3-(4-hydroxyphenyl)acrylic acid, (p-Hydroxycinnamic acid), cinnamic acid, [1,1′-biphenyl]-4-carboxylic acid, [1,1′:4′,1″-terphenyl]-4-carboxylic acid, [1,1′:4′,1″-terphenyl]-2-carboxylic acid, 2-naphthoic acid, 2-(naphthalen-2-yl)acetic acid, 9-fluorenyl methoxy carboxylic acid.
In still another embodiment of the present invention a peptidomimetic derivatives according to the structure I and II wherein R can be an aliphatic acid moiety conjugated with amide bond (—CONH—), at the C-terminal is specified as
Further R can be unsaturated fatty acid such as oleic acid, linoleic acid or linolenic acid.
In certain embodiment in the structures claimed above the AA1 and AA2 are amino acids, wherein the amino acids can be tryptophan (W), Ornithine (O) lysine (K) or phenylalanine (F) or combinations of two amino acids. The sequence of dipeptide can be —WW—, —WO—, —WK—, —WF—, —OW—, —OO—, —OK—, —OF—, —FF—, —FW—, —FK—, —FO—.
The peptidomimetics designed in present invention were evaluated as antibacterial therapeutics against a broad range of bacterial strains by broth microdilution method. The antibacterial activity of the peptidomimetics was reported in terms of the minimum inhibitory concentrations (MIC). The term “MIC” refers to the lowest drug concentration that completely inhibits bacterial growth after 18-24 h incubation at 37° C.
Herein by “bacteria” we refer to both Gram-positive and Gram-negative bacteria. Examples of Gram negative bacterial speciesmay be as follows: Acinetobacter, Bordetella, Citrobacter, Escherichia, Fusobacterium, Haemophilus, Klebsiella, Proteus, Yersinia and Pseudomonas species. Examples of Gram positive bacterial species include Streptococcus, Staphylococcus, Actinomyces and Clostridium.
In one feature of the invention, the peptidomimetics showing antibacterial activity were found to exert cell selective interactions as they are lytic particularly to the bacterial cell and non-toxic to the mammalian cells. The toxicity of peptidomimetics was screened by hemolytic activity against human RBCs and Lactate dehydrogenase [LDH] release assay on the peripheral blood mononuclear cells.
The present invention further provides the mode of action of designed active peptidomimetics against methicillin resistant S. aureus . Among the peptidomimetics the most active peptidomimetics showed rapid bactericidal kinetics, membrane depolarization and membrane disruptive mode of actions against MRSA. The mode of action was corroborated by the various biophysical and microscopic tools and techniques. The details of the mode of action studies have been given in the following examples.
MRSA is an extraordinary pathogen associated high mortality rates in clinical settings due to its virulence, multidrug-resistant profile, and prevalence in community and nosocomial environments. In yet another embodiment of the present invention it was found that the active molecules were effective to eradicate the bacterial cells embedded in MRSA biofilms. The term ‘biofilm’ here means microbial populations adhered to polystyrene surface (for different duration of time, young biofilms 6 h and mature biofilms 24 h) and producing slime due to accumulation of extracellular polymeric substance (EPS). The EPS matrix generally is composed of biopolymers including polysaccharides, proteins, nucleic acids and lipids.
In another embodiment of the invention these peptidomimetics inhibited the biofilms formation/eradicated preformed biofilm of MRSA formed on the biotic/abiotic surface. For determination of biofilm formation/killing abilities, we used a combination of the alamar blue assay (for measurement of viability) and crystal violet assay (for quantification of biomass).
It should be noted that in all the mentioned embodiments the present invention provides a novel and potent class of membrane-active antibacterial peptidomimetics against multidrug resistant infections that are also able to eradicate clinically relevant 24 h mature MRSA biofilms. Further evaluation of prevention of biofilm formation on solid supports like medical devices would broaden therapeutic applications of these peptidomimetics in clinical settings.
In another embodiment, a process for the preparation of peptidomimetics (1a-1f) of the present invention comprising the steps of:
pre-swelling the resin in DMF:DCM for a period ranging between 2 h to 4 h at a temperature in the range of 25 to 30° C. followed by adding spermine in a solvent to obtain pre-swelled resin;
capping the pre-swelled resin obtained in step (a) by using the solvent (capping agent) for a period of time 30 min followed by protecting the terminal primary amino group of spermine with Dde-OH in DMF for a period of time ranging between 6 h to 12 h followed by protecting secondary amino group by using the Boc-anhydride in the presence of catalyst for a period of time ranging between 2 h to 4 h to obtain protected resin;
removing the Dde protection of terminal primary amino group from the protected resin obtained in step (b) by using 2% solution of hydrazine in a solvent followed by coupling of N-terminal amino group with Fmoc-Trp(Boc)-OH in the presence of HOBt and DIPCDI followed by removal of Fmoc group by 20% piperidine. Again the N-terminal was coupled with second Fmoc-Trp(Boc)-OH in the presence of HOBt and DIPCDI followed by removal of Fmoc group by 20% piperidine to get dipeptide and finally N-terminal amino group was tagged by R group using HOBt and DIPCDI in DCM:DMF to obtain peptidomimetics (1a-1f);
finally deprotecting the peptidomimetics from resin obtained in step (c) by using (DCM:TFA:ethanedithiol:triisopropylsilane:phenol:water: in ratio 65:30:2:1:1:1) followed by precipitation and washing to get peptidomimetics (1a-1f)
In another embodiment, a process for the preparation of peptidomimetics (2a-2f) of the present invention comprising the steps of:
pre-swelling the resin in DMF:DCM for a period ranging between 2 h to 4 h at a temperature in the range of 25 to 30° C. followed by adding spermine in a solvent to obtain pre-swelled resin;
capping the pre-swelled resin obtained in step (a) by using the solvent (capping agent) for a period of time 30 min followed by protecting the terminal primary amino group of spermine with Dde-OH in a solvent for a period of time ranging between 6 h to 12 h followed by coupling with Boc-Trp(Boc)-OH, HOBt, DIPCDI in a mixture of solvent to get the protected resin;
removing the Dde-OH protection of terminal primary amino group from the protected resin obtained in step (b) by using 2% solution of hydrazine in a solvent followed by coupling with N-terminal tagging (R group) in the presence of HOBt and DIPCDI in a mixture of solvent DCM:DMF to obtain peptidomimetics (2a-2f);
finally deprotecting the peptidomimetics from resin obtained in step (c) by using (DCM:TFA:ethanedithiol:triisopropylsilane:phenol:water: in ratio 65:30:2:1:1:1) followed by precipitation and washing to get peptidomimetics (2a-2f).
In another embodiment of the invention, these peptidomimetics are formulated along with pharmaceutically acceptable drug delivery vehicle to obtain a composition. The said composition comprises any of the peptidomimetics in the form of emulsions, liquids, cream, ointment or paste alone or in combination. Further, the composition comprising any of the peptidomimetics of the present invention may be useful for treatment of skin infections, systemic infections, burns or wounds healing in humans or animals.
EXAMPLES
The following examples are given by way of illustration of the present invention and therefore should not be construed to limit the scope of the present invention.
Example 1
Fmoc-protected amino acids and resins were purchased from Novabiochem (Darmstadt, Germany), N, N-Diisopropylcarbodiimide (DIPCDI, cat. no. D12, 540-7), 1-hydroxy-benzotrizole (HOBt, cat. no. 54804), Di-isopropylethylamine (DIPEA, cat. no. D-3887), N-methylpyrrolidinone (NMP, cat. no. 494496), piperidine (cat. no. 411027), spermine (cat. no. S3256), triisopropylsilane (TIS, cat. no. 23378-1), crystal violet (cat. no. C3886), glucose (cat. no. G7528), hydrazine (cat. no. 225819), 3,3′-dipropylthiadicarbocyanine iodide (DiSC35, cat. no. 43608) and TOX-7 kit (LDH release assay kit) were obtained from Sigma-Aldrich. Trifluoroacetic acid (TFA, cat. no. 80826005001730) and 2-Acetyldimedone (Dde-OH, cat. no. 8.51015.0005) were purchased from Merck company. All the moieties used as N-terminal tag were purchased from Sigma-Aldrich. Tryptone Soya broth (TSB, cat. no. M011-500G) was purchased from HIMEDIA, India and Mueller Hinton broth (MHB) and agar were purchased from DIFCO (Franklin Lakes, N.J., USA). Alamar blue reagent (cat. no. DAL 1025) and LIVE/DEAD BacLight (L7012) assay kit were procured from Invitrogen (Molecular Probes, Eugene, Oreg., USA). HPLC grade and solvents were obtained from Merck (Germany). Dimethylformamide (DMF) and dichloromethane (DCM) were obtained from Merck (Mumbai, India). DMF was double distilled prior to use.
Example 2
Synthesis and Characterization of Peptidomimetics
The peptidomimetics were synthesized by solid phase peptide synthesis on 2-chlorotrityl chloride resin using Fmoc strategy as described previously with minor modifications [ Tetrahedron Lett. 41, 1095-1098, 2000]. Briefly, the resin was pre-swelled in DMF:DCM (1:1, v/v) for 2 h and then 5 eq. of spermine (in DCM) was added. The reaction was run for 4 h under inert atmosphere. Completion of reaction was monitored through Kaiser Test [ Anal. Biochem., 34: 595-598, 1970]. After coupling, the resin was capped with methanol for 30 min. The terminal primary amino group of spermine was protected with 2 eq. of Dde-OH in DMF overnight. After protection of primary amino group, secondary amino groups were protected with 6 eq. of Boc-anhydride in presence of DIPEA for 4 h. Then Dde-OH protection of primary amines was removed using 2% w/v hydrazine (in DMF). Further two couplings were done with Fmoc-Trp(Boc)-OH in presence of HOBt and DIPCDI in DCM:DMF (1:1). The N-terminal tagging was done with 4 eq. of unnatural tag, HOBt and DIPCDI in DCM:DMF (1:1) leading to peptidomimetics 1a-1f (Scheme 1).
Reagents and Conditions:
1) 5 eq. Spermine, DCM, 3 h, 2) MeOH for 30 min. 3) 2 eq. Dde-OH, DMF, overnight 4) 6 eq. (Boc) 2 O, DCM:DMF (1:1), 3 h, 5) Boc-Trp(Boc)-OH, HOBt, DIPCDI, DCM:DMF (1:1), overnight, 6) 2% hydrazine (DMF), 7) Fmoc-Trp(Boc)-COOH, HOBt, DIPCDI, DCM:DMF (1:1), 1.5 h, 8) 20% piperidine (DMF), 9) 3 eq. R—COOH, HOBt, DIPCDI, DCM:DMF (1:1), overnight, 10) 30% TFA/DCM.
For syntheses of peptidomimetics 2a-2f, Dde-OH protected resin was coupled with 4 eq. of Boc-Trp (Boc)-OH, HOBt and DIPCDI. Thereafter, deprotection of primary amine group was done with 2% w/v hydrazine in DMF. The N-terminal tagging was achieved as described above. Final deprotection of peptidomimetics from resin in both series was performed using a cleavage cocktail (DCM:TFA:ethanedithiol:triisopropylsilane:phenol:water: in ratio 65:30:2:1:1:1). The cleavage cocktail was filtered and to the filtrate cold diethyl ether was added to effectuate peptide precipitation. After washing the crude peptide twice, the solid was dissolved in methanol and desalted using LH-20 sephadex (Sigma) column. Further the peptidomimetics were purified on RP-HPLC, using a semi-preparative column (7.8×300 mm, 125 Å, 10-μm particle size) with gradient of 10 to 90% buffer 2, where, buffer 1 was water (0.1% TFA) and buffer 2 was acetonitrile (0.1% TFA) over 45 min. The peptidomimetics after purification were confirmed either by LC-MS/MS (Quattro micro API, Waters) or UHPLC (Dionex, Germany) and LTQ Orbitrap XL (Thermo Fisher Scientific, USA) mass determination. All the designed peptidomimetics were >80% pure and their masses were in the range of 575-850 Da (Table 1).
TABLE 1
Peptidomimetics, % purity, % acetonitrile at RP-HPLC
elution and molecular mass of designed peptidomimetics
% of
Mass [M + H] +
Peptidomimetics
Purity
acetonitrile a
Calc.
Obs.
1a
95
17.41
575.3816
575.3808
1b
99
46.42
737.4133
737.4139
1c
95
54.72
761.4109
761.4110
1d
95
61.57
729.5174
729.5178
1e
95
65.21
757.5487
757.5489
1f
98
70.36
837.6113
837.6097
2a
80
12.30
575.3816
575.3815
2b
80
44.34
737.4133
737.4140
2c
83
49.85
761.4109
761.4118
2d
99
57.92
729.5174
729.5181
2e
99
62.63
757.5487
757.5495
2f
99
69.78
837.6113
837.6113
a Percentage of acetonitrile at RP-HPCL elution of peptidomimetics
Example 3
Antibacterial Activity
Following bacterial strains were used in this study: S. aureus (ATCC 29213), methicillin resistant S. aureus (ATCC 33591), Staphylococcus epidermidis (ATCC 12228), methicillin resistant Staphylococcus epidermidis (ATCC 51625), Enterococcus faecalis (ATCC 7080), Escherichia coli (ATCC 11775), and Acinetobacter baumannii (ATCC 19606). Antibacterial activity was evaluated using a modified serial broth dilution method in accordance with Clinical Laboratory Standard Institute guidelines [ Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically -7 th ed. Approved standard M 7- A 7 . Clinical and Laboratory Standards Institute, Wayne, Pa., Biochim. Biophys. Acta 1798:1864-1875, 2010.]. Briefly, the inoculums were prepared from mid-log phase bacterial cultures. Peptidomimetics were incubated with bacterial suspension in Muller Hinton broth media (10 5 CFU/mL) in 96 well microtitre plate. The plates were incubated overnight with agitation (200 rpm) at 37° C. After 18 h, absorbance was measured at 630 nm. Cultures without test peptidomimetics were used as positive control. Un-inoculated Mueller Hinton Broth (MHB) was used as negative control. Tests were carried out in duplicate on at least three different days. Minimum inhibitory concentration (MIC) is defined as the lowest concentration of peptidomimetics that completely inhibited growth. For comparison standard peptide antibiotics vancomycin (VAN) and polymyxin B (PMB) were also assayed under identical conditions (Table 2). Template peptidomimetics 1a showed moderate activity against Gram-positive bacterial strains while peptidomimetics 1b-1f displayed good activity with MIC <10 μg/mL against all the tested strains except E. faecalis . Against Gram-negative bacteria E. coli also peptidomimetics in series 1 showed activity with MIC in the range of 14.2-56.8 μg/mL. In series 2 peptidomimetics 2a and 2b showed poor activity, while peptidomimetic 2c showed moderate activity, but, 2d-2f exhibited good growth inhibition of all the bacterial stains tested (MIC: 0.8-28.4 μg/mL) except A. baumannii . Standard antibiotic PMB showed relatively poor activity against Staphylococcus species, although it showed excellent growth inhibition of Gram-negative bacterial strains. VAN showed potent growth inhibition for Staphylococcus species, however, was ineffective against Gram-negative strains under the experimental conditions. Further, antibacterial activity of active peptidomimetics 1c and 1d were also evaluated against MRSA in presence of 25% v/v human serum as well as bovine serum. A 4 fold and 8 fold increase in MIC was observed for 1c and 1d, respectively, in human serum.
TABLE 2
Antibacterial activity of peptidomimetics against Gram-positive and
Gram-negative bacterial strains and cytotoxicity against blood cells
MIC(μg/L)
S. aureus
MRSA
S. epidermidis
MRSE
E. facaelis
E. coli.
A. baumannii
(ATCC
(ATCC
(ATCC
(ATCC
(ATCC
(ATCC
(ATCC
% H a
% LDH b release
29213)
33591)
12228)
51625)
7080)
11775)
19606)
(250 μg/mL)
(20 μg/mL)
1a
113.6
227.2
113.6
ND
454.5
ND
ND
4
ND
1b
3.5
7.1
3.5
7.1
113.6
14.2
ND
16
ND
1c
1.7
3.5
1.7
3.5
28.4
56.8
28.4
2
5.78
1d
1.7
1.7
1.7
1.7
3.5
14.2
113.6
9
17.5
1e
1.7
3.5
1.7
1.7
7.1
14.2
56.8
31
ND
1f
7.1
3.5
1.7
7.1
28.4
28.4
ND
30
ND
2a
>454.4
>227.2
>454.4
227.2
ND
>454.4
ND
0
ND
2b
>454.4
454.4
ND
ND
ND
>454.4
ND
5
ND
2c
14.2
28.4
7.1
14.2
ND
113.6
113.6
1
ND
2d
0.8
1.7
0.8
1.7
28.4
28.4
113.6
83
ND
2e
0.8
1.7
0.8
1.7
7.1
28.4
113.6
96
ND
2f
0.8
3.5
0.8
1.7
14.2
28.4
56.8
88
ND
PMB
14.2
28.4
7.1
28.4
113.6
0.4
ND
ND
ND
VAN
0.4
0.8
0.4
0.8
ND
113.6
56.8
ND
ND
a Percentage hemolysis of human RBCs,
b % LDH release against peripheral blood mononuclear cells
Example 4
Hemolytic Activity
Hemolytic activity of the peptidomimetics was evaluated on human red blood cells (hRBC) as described previously with minor modifications [ FEBS J, 273:4040-4054, 2006 ; Biochim Biophys Acta., 1798:1864-1875, 2010]. Briefly, 100 μL of fresh hRBC suspension 4% v/v in NaCl/Pi (35 mM phosphate buffer, 150 mM NaCl, pH 7.2) was placed in a 96-well plate. After incubation of the peptidomimetics (100 μL) in the hRBC suspension for 1 h at 37° C., the plates were centrifuged and supernatant (100 μL) was transferred to fresh 96-well plate. Absorbance was read at 540 nm using ELISA plate reader (Molecular Devices). Percent hemolysis was calculated using the following formula:
% hemolysis=100[( A−A 0 )/( A t −A 0 )]
Where, A represents absorbance of sample wells at 540 nm. Also A 0 and A t represents 0% and 100% hemolysis determined in NaCl/Pi and 1% Triton X-100, respectively (Table 2). Most of the peptidomimetics including 1a-1d, and 2a-2c were found to cause minimal hemolysis up to the maximum concentration tested. Peptidomimetics 1e and 1f caused 31% and 30% hemolysis at 250 μg/mL. Peptidomimetics 2d, 2e and 2f caused significant hemolysis with 83%, 96% and 88% damage to hRBCs at 250 m/mL respectively.
Example 5
Cytotoxicity Assay in Peripheral Blood Mononuclear Cells (PBMCs)
For the experiment a protocol as used previously was employed with minor modifications [ J. Immunol. Methods, 115:61-69, 1988 ; Chem. Biol. 20:1286-1295, 2013.]. Briefly, blood was collected from healthy human donors in sodium heparin anticoagulant tubes in accordance with institutional guidelines. The blood was diluted 1:1 with NaCl/Pi (35 mM phosphate buffer, 150 mM NaCl, pH 7.2). Blood cells were separated over histopaque (Sigma-aldrich) by centrifugation for 30 min at 1200 rpm. The PBMCs were collected and washed twice with NaCl/Pi (35 mM phosphate buffer, 150 mM NaCl, pH 7.2). The cells were then re-suspended in complete RPMI 1640 medium (Himedia) supplemented with 10% FBS (Sigma) and quantified by trypan blue exclusion on microscope. PBMCs (1×10 6 cells/mL) in complete media were seeded into a 24-well plate and left in the incubator for 2 h at 37° C. in 5% CO2. The cells were then treated with 1c, 1d and VAN at desired concentrations (20 μg/mL). 2% Triton X-100 was used as a negative control. After 24 h of incubation, the content of each well was transferred to sterile 1.5 mL eppendorf tube and cells were pelleted at 2000 rpm for 10 min. The supernatant was assessed for the release of LDH by using the TOX7 kit (Sigma). The experiments were carried out in duplicate on three different days and data is presented as mean±S.D. At 20 μg/mL concentrations 5.78±6.58% and 17.56±10.15% LDH release was caused by 1c and 1d, respectively (Table 2).
Example 6
Membrane Depolarization Mode of Action
For determination of membrane depolarizing ability of designed peptidomimetics, a membrane potential sensitive dye DiSC 3 (5) was used as described previously with minor modifications [ Org Biomol. Chem. 10: 8326-8335, 2012 ; J. Am. Chem. Soc., 132: 18417-18428, 2010.]. Briefly, overnight grown MRSA was sub cultured into MHB for 2-3 h at 37° C. to obtain mid-log phase cultures. The cells were centrifuged at 4000 rpm for 10 min at 25° C., washed, and re-suspended into respiration buffer (5 mM HEPES, 20 mM glucose, pH 7.4) to obtain a diluted suspension of OD 600 ˜0.05. Then DiSC 3 (5) [0.18 μM in DMSO], was added to 500 μL aliquotes of the re-suspended cells and allowed to stabilize for 1 h. Baseline fluorescence was acquired using a Edinburg F900 spectrofluorometer by excitation at 622 nm and emission at 670 nm in a 1 cm path length cuvette. Bandwidth of 5 nm was employed for excitation and emission. Subsequently, increasing concentrations of test peptidomimetics were added to the stabilized cells and the increase of fluorescence on account of the de-quenching of DiSC 3 (5) dye was measured after every 2 min to obtain the maximal depolarization. Increase in relative fluorescence unit (RFU) was plotted against increasing concentrations of different peptidomimetics or PMB. For peptidomimetics 1a and 2a, only minor increase in relative fluorescence unit (RFU) were observed up to the maximum concentration tested, suggesting inability of these peptidomimetics to alter membrane potential at concentrations below MIC (data not shown). For peptidomimetics 1c and 2c with aromatic N-terminal tags, only marginal changes in RFU were observed up to the highest concentration tested ( FIG. 2 ). For peptidomimetics 1d and 2d, intermediate changes in fluorescence intensity were observed, whereas for peptidomimetics 1e, 1f, 2e and 2f, significant changes in RFU were observed. The increase in fluorescence for lipid tagged peptidomimetics was concentration dependent up to 9.9 μg/mL and henceforth, got saturated resulting into plateau like dose response curves. The experiment was repeated twice on two consecutive days and produced similar results.
Example 7
Killing Kinetic Study
The killing kinetics of MRSA (ATCC 33591) by peptidomimetics was evaluated as described previously with minor modifications [ Antimicrob. Agents Chemother., 18: 699-708, 1980.]. Briefly, log-phase bacteria (1.2-3.0×10 7 CFU/mL) were incubated with peptidomimetics 1c, 1d and VAN at 2× and 4× their respective MIC in MHB. Aliquots were removed after fixed time interval (0.5, 1, 2, 3, and 6 h) and diluted appropriately in sterile saline before plating on the Mueller Hinton II agar. The plates were incubated for at 37° C. for 24 h and CFU were counted. At 2×MIC, both peptidomimetics reduced ≧3−log 10 CFU/mL within 3 h of incubation whereas at 4×MIC, bactericidal effect was observed within 30 min of incubation by reduction of >4−log 10 CFU/mL ( FIG. 3 ).
Example 8
Scanning Electron Microscopy (SEM)
To visualize the effect of peptidomimetics on MRSA cells we carried out electron microscopic investigation using a protocol described previously with slight modifications [ Antimicrob. Agents Chemother., 55:1920-1929, 2011 ; Antimicrob Agents Chemother., 58:5435-5447, 2014.]. For this, freshly inoculated MRSA (ATCC 33591) was grown on MHB up to OD600˜0.5 (corresponding to 10 8 CFU/mL). Bacterial cells were then spun down at 4000 rpm for 15 min, washed thrice with NaCl/Pi (10 mM phosphate buffer, 150 mM NaCl, pH 7.4) and re-suspended in equal volume of NaCl/Pi. For SEM experiment, a higher bacterial inoculums (10 8 CFU/mL) was used therefore the cells were incubated with test peptidomimetics 1c, 1d or VAN at respective 10×MIC for 30 min. Controls were run in the absence of antibacterial agents. After 30 min, the cells were spun down and washed with NaCl/Pi thrice. For cell fixation, the washed bacterial pallet was re-suspended in 0.5 mL of 2.5% paraformaldehyde in NaCl/Pi and was incubated at 4° C. for overnight. After fixation, cells were spun down and washed with 0.1M sodium cacodylate buffer twice and fixed in 1% osmium tetraoxide in 0.1M sodium cacodylate buffer at RT for 40 min in dark. Further the samples were dehydrated in series of graded ethanol solutions (30% to 100%), and finally dried in desiccators under reduced pressure. Upon dehydration, the cells were air dried for 15 min in dark at RT after immersion in hexamethyldisilazane. An automatic sputter coater (Quorum-SC7640) was used for coating the specimens with thickness of 30 A° gold particles. Then samples were imaged via scanning electron microscope (Zeiss EVO LS15). Control MRSA cells exhibited bright smooth appearance with intact cell membrane ( FIG. 4A ). Peptidomimetic 1c treatment caused rough and damaged surfaces, cell bursting, leakage and string-like substances, which are considered to be cellular debris arising from cell lysis ( FIG. 4B ). For peptidomimetic 1d treated cells appeared distorted with depression and hole formation ( FIG. 4C ), indicating the membrane active mode of action for designed peptidomimetics. Surprisingly, VAN treated cells mostly retained their smooth appearance, albeit slight deformations in shape of cells as compared to control cells ( FIG. 4D ).
Example 9
Resistance Development Study
To determine potential of active peptidomimetics against resistance development, in vitro serial passage method at sub inhibitory concentration was done. Briefly, bacterial suspension (100 μL) from duplicate wells at the concentration of sub-MIC was used to inoculate fresh culture. The culture was grown to obtain approximately 10 5 CFU/mL for the next experiment. These bacterial suspensions were then incubated with desired concentration of antibacterial agents for 18 h to determine new MIC. The same sub culturing protocol was used for next 16 passages and MIC was determined using OD 630 nm as described previously in the text [ Chem. Biol., 20:1286-1295, 2013.] A 4 fold and 2 fold increase in MIC was observed for 1c and 1d respectively ( FIG. 5 ). For standard antibiotics VAN after 17 passages, the MIC was increased by 4 fold, whereas for ciprofloxacin (CIP), a radical change of 256 fold in MIC was observed.
Example 10
Biofilm Susceptibility Assay
To evaluate potential of designed active peptidomimetics against MRSA biofilms a methodology as used previously was employed with minor modifications [ Antimicrob. Agents Chemother., 57:2726-2737, 2013]. Briefly, freshly inoculated MRSA (ATCC 33591) was grown in biofilm growth media (TSB supplemented with 0.5% w/v NaCl and 0.25% w/v glucose) overnight. Next day, the culture was diluted in fresh biofilm growth media to 10 5 CFU/mL. 200 μl of diluted culture was dispensed in wells of a 96-well polystyrene plate for biofilm formation. To evaluate the inhibition of biofilm formation, antibacterial agents at MIC b (planktonic MIC in biofilm media) and sub-MIC b concentrations were added initially with diluted culture following incubation at 37° C. without shaking Another set of experiment was performed by addition of fresh medium containing antibacterial agents at 10×MIC b and 20×MIC b concentrations after gently washing by sterile NaCl/Pi buffer (35 mM phosphate buffer, 150 mM NaCl, pH 7.4) to 24 h preformed biofilm. Biofilm cultures were re-incubated at 37° C. for 24 h. After removal of medium, the biofilms were further washed twice with sterile NaCl/Pi buffer and assessed for metabolic activity (alamar blue assay) and biomass quantification (Crystal violet assay).
For visualization of biofilm and validation of AB and CV assay we performed confocal microscopy. For this biofilm formation was induced on glass cover slips in a 6-well plate. The biofilm on cover slips were washed twice with sterile NaCl/Pi buffer and stained with a Live/Dead kit reagent (Invitrogen, Molecular Probes, Eugene, Oreg., USA) following the manufacturer's instructions. This stain contains DNA binding dyes SYTO 9 (green fluorescent) and propidium iodide (PI; red fluorescent). When used alone, SYTO 9 stains all bacteria in a population, those with intact as well as damaged membranes. In contrast, PI penetrates only bacteria with damaged membranes, causing a reduction in the SYTO 9 stain (green fluorescence). The biofilms were examined with an Olympus flow view FV1000 (confocal laser scanning microscope, CLSM). The experiment was repeated three times on three different days and representative data is presented here.
Peptidomimetics 1c and 1d were able to halt biofilm formation at sub-MIC b concentrations as was evaluated using AB assay whereby a reduction in metabolic activity up to 33.1±5.7% and 26.4±3.3%, respectively was observed for 1c and 1d treated cells respectively. Similarly, % biomass reduction was found to be 19.8±5.6% and 28.2±11.1% for 1c and 1d respectively ( FIGS. 6A and 6B ). At MIC b concentration both peptidomimetics inhibited adhesion of biofilm causing >90% reduction in measured viability and biomass quantity. Further, against 24 h pre-formed mature biofilms at 20×MIC b designed peptidomimetics 1c (140 μg/mL) and 1d (70 μg/mL) showed better killing profiles with 6.4±0.2 and 10.1±7.8% viable cells, respectively in comparison to 77.7±7.0% viable cells for VAN (20 μg/mL) at the indicated concentration ( FIG. 6C ). In parallel peptidomimetic 1c (at 140 μg/mL concentrations) and 1d (at 70 μg/mL concentrations) reduced biomass to 24.0±13.4% and 21.4±9.2% respectively as compared to control biomass ( FIG. 6D ). For VAN even at 20×MIC b (20 μg/mL) the biomass remaining was 83 0.7±24.1%.
We next measured the thickness of biofilm using z-stacking in confocal microscopy. The control biofilm (24 h) showed a lawn of viable (green) cells with average thickness 14.3±1.4 μm ( FIG. 7A ). At MIC b , 1c and 1d prevented formation of biofilm in which very few cells were adhered to substratum with observed average thickness of 3.9±1.1 μm and 3.5±0.6 μm, respectively. Furthermore, at sub-MIC b concentration the observed thicknesses were 5.2±0.3 μm and 5.8±0.4 μm ( FIG. 7A .b and FIG. 7A .d). In case of VAN at MIC b , the measured thickness of biofilm was 11.4±2.9 μm ( FIG. 7A .g), whereas at sub-MIC b VAN was unable to reduce biofilm thickness.
Untreated 48 h mature biofilm (24+24) showed a lawn of viable (green) cells with average thickness of 23.6±2.5 μm ( FIG. 7B ). Subsequent to treatment with 1c and 1d at concentrations of 10×MIC b , in FIGS. 7B .b and 7 B.d, there were visual decrease in the number of live cells and thickness was reduced to 7.1±1.5 and 7.0±1.0 μm, respectively. For peptidomimetics 1c and 1d, most of the cells lost their integrity at 20×MIC b , appearing red ( FIG. 7B .c and FIG. 7B .e) and a smear of permeabilized cells was observed. Up on VAN treatment, no significant difference in number of live cells was observed as mixed bacterial population stained green was visible at both the tested concentrations. VAN had little effect on 24 h biofilm at 10×MIC b where no distinction between control biofilm and VAN treated biofilms were visible. Only at 20×MIC b of VAN, slight decrease in the height of mature biofilm was observed ( FIGS. 7B .f and 7 B.g). The confocal imaging experiments were repeated three times on three different days and similar results were obtained (representative data of one set is shown here).
Example 11
Serum Stability Assay
To determine activity of designed peptidomimetics in physiological fluids serum stability was evaluated using a standard reverse phase HPLC method as described previously with slight modifications [ Antimicrob. Agents Chemother., 54: 4003-4005, 2010]. Towards this the peptidomimetics were dissolved in pre-warmed 25% v/v human serum in 0.1M phosphate buffer saline (150 mM NaCl, pH 7.2) at final concentrations of 150 μg/ml and incubated at 37° C. At fixed time interval (0, 4, 24, 48, and 72 h) aliquots of 1004 incubation mixture were withdrawn in duplicates. The mixture was precipitated with a mixture of acetonitrile, water, and formic acid (300 μl; 89:10:1 by volume) on ice. After 45 min on ice, the samples were centrifuged (10 min, 12,000 g, at 4° C.) and the supernatants were analyzed by RP-HPLC with UV detection at 220 nm using the same column and data system as described above for characterization. The results demonstrated >85% intact peptidomimetics even after 72 h of incubation. | N-terminally modified linear and branched polyamine conjugated peptidomimetics as antimicrobials agents. The invention relates to therapeutically viable antibacterial compositions based on ultra short mimetic of host defense cationic peptides (HDCPs). The invention relates to template based N-terminal modified di-peptidomimetics with or without modifications in polyamine backbone as new antibacterial agents. Most active peptidomimetics were bactericidal and caused a rapid decrease in viability of broad range of Gram-positive and Gram-negative bacterial strains in low micromolar concentration range including activity against clinically relevant pathogen methicillin resistant S. aureus (MRSA) andmethicillin resistant S. epidermidis (MRSE). Further the peptidomimetics were effective against MRSA biofilms (formation inhibition/killing of preformed biofilms) in vitro and were non toxic to human red blood cells and peripheral blood mononuclear cells. The molecules described in present invention do not develop resistance against MRSA under in vitro conditions and hence may be used as topical agents or in similar applications. | 2 |
CROSS REFERENCE TO RELATED PATENT APPLICATIONS
The present patent application claims the right of priority under 35 U.S.C. §119( a )-( d ) of German Patent Application Numbers 199 09 786.0, filed Mar. 5, 1999, and 199 51 734.7, filed Oct. 27, 1999.
FIELD OF THE INVENTION
This invention relates to esters of oligo- and polysaccharides which are regio-selectively substituted, predominantly at the C2 position of the anhydroglucose unit (AGU), and also relates to a method of producing them using enzymes and/or defined salts as catalysts for ester formation. Regioselectively substituted esters of this type have basic properties which are different from those of conventional, randomly functionalised products.
BACKGROUND OF THE INVENTION
It is known that when oligo- and polysaccharides are subjected to esterification by conventional methods, products are formed which exhibit a random distribution of the esters groups within the AGU and along the chain. This randomness depends on the accessibility to electrons or on the spatial accessibility of the individual hydroxyl groups. Thus in starch, for example, the hydroxyl group in the C6 position is a primary group which is very sterically accessible and which thus exhibits the highest accessibility during heterogeneous reactions in particular. The hydroxyl function of the C2 position forms the basis of the electronic effect of the adjacent glycoside bond and of the electron-attracting properties of the ring oxygen. In homogeneous processes, it has been shown that the C2 position reacts first for this reason. In none of the aforementioned situations, however, is the complete reaction of only one hydroxyl group achieved.
By utilising differences in accessibilities such as these, hydroxyl groups can be selectively blocked with the aid of protective groups, which are generally bulky and can easily be split off, so that regioselective derivatives are formed in subsequent reactions.
Examples of protective groups such as these include triphenylmethyl groups or bulky organosilicon entities such as t-hexyl- or tert-butyl-dimethylsilyl groups.
However, this type of synthesis has the decisive disadvantage that at least two additional reaction steps are necessary due to the introduction of the protective group and the separation thereof. Other disadvantages are the fact that the separation of the protective groups is sometimes incomplete, which means that the cleavage products which are formed thereby, and which are sometimes toxic, have to be removed without leaving a residue, as well as the breakdown of the polysaccharide chain which is possible under the conditions of cleavage and which changes the properties of the product.
When a plurality of reactive centres, e.g. hydroxyl groups, exists in a molecule, enzymes are capable of catalysing direct, selective esterification reactions. In this connection, each enzyme has a certain folded (native) structure which is essential for its specific biocatalytic activity in the physiological medium concerned. It has been shown in numerous publications, however, that many enzymes are also active in organic solvents, i.e. are active irrespective of their native structure, size and function. Enzymes generally exhibit a high activity in nonpolar solvents, whereas only very low activities are found in relatively polar media (Biotechnol. Bioeng. 30 (1987), 81-87). Enzymes are insoluble in the latter organic solvents.
Numerous enzyme-catalysed reactions of this type have already been carried out on low molecular weight mono- and disaccharides in organic solvents (FEMS Microbiol. Rev. 16 (1995), 193-211; J. Prakt. Chem. 335 (1993), 109-127; Synthesis 1992, 895-910; WO 97/36000; WO 95/23871). In these reactions lipases have primarily been used as the enzymes, although esterases and proteases have also been used, and solvents such as tetrahydrofuran, pyridine and N,N-dimethylformamide have been employed. Enzymatic esterifications can also be effected in an aqueous buffer solution. One disadvantage here is that the acylating reagent, which has a character similar to that of a fatty acid, is insoluble in the aqueous buffer solution and can thus only be suspended therein. The substrate which is to be esterified is present in dissolved form (DE-A-34 30 944,1992; JP-A-63191802).
Glucans generally result in the formation of esters at primary hydroxyl groups. In some cases, esterification also occurs at secondary hydroxyl groups (J. am. Chem. Soc. 109 (1987), 3977-3981; Enzyme Microb. Technol. 20 (1997), 225-228). Compounds which comprise electron-attracting groups are generally used for the aforementioned enzymatic esterifications, such as vinyl esters (Biotechnol. Lett. 19 (1997), 511-514) or trihalogenoethyl esters (Tetrahedron 54 (1998), 3971-3982); esterification by a vinyl ester constitutes an irreversible reaction, since the vinyl alcohol which is formed is removed as acetaldehyde from the reaction equilibrium. Other reactive compounds include carboxylic anhydrides and esters of carbonic acid.
Diesters of dicarboxylic acids have also been used for reaction with mono- and disaccharides. In this manner, it has proved possible to synthesise new saccharide-based copolymers, as disclosed in U.S. Pat. No. 5,270,42 1 and U.S. Pat. No. 5,618,933.
In the publications described above, the substrate and the acylating reagent are generally dissolved in an organic solvent, in which the enzyme is then suspended. Enzymatic esterifications cannot be effected on polysaccharides, particularly glucans, by the methods cited above, since the undissolved or unswollen polymer is not accessible to the enzyme or to enzyme catalysis. Polysaccharides can be esterified enzymatically in a heterogeneous phase, however (WO 96/13632, DE-A-34 30 944). These heterogeneous reactions only proceed at the surface of the polymer particles, due to which inhomogeneously esterifed polysaccharide derivatives are formed, i.e. polysaccharide derivatives which comprise a non-uniform distribution of substituents along the polymer chain. Other disadvantages of this method of esterification are that low yields of product are obtained and products are formed which comprise a low degree of selectivity as regards the type of substitution in the anhydroglucose unit.
Conventional heterogeneous esterifications are often conducted in water as a suspension medium (U.S. Pat. No. 5,703,226, 1997). Homogeneous reactions are conducted in organic solvents or in the acylating reagent directly (U.S. Pat. No. 5,714,601, 1998; WO 96/14342). The corresponding carboxylic anhydrides or vinyl esters are generally used as acylating agents. Esterifications or transesterifications of this type are mostly catalysed by alkalies, wherein suitable catalysts include alkali hydroxides, salts of mineral acids or organic amines.
SUMMARY OF THE INVENTION
The object of the present invention was to enable esters of oligo- and polysaccharides to be obtained which are homogeneously and regioselectively substituted at the C2 position of the anhydroglucose unit (AGU). Success has now been achieved according to the invention in producing esters of oligo- and polysaccharides which are homogeneously and regioselectively substituted at the C2 position of the AGU. The present invention therefore relates to oligo- and polysaccharide esters which are esterified regioselectively, with ester groups at the C2 position of the AGU preferably amounting to at least 90%, most preferably 90 to 98%, of the total degree of substitution (partial average degree of substitution AS at the C2 position of the AGU with respect to the total AS). The oligo- and polysaccharide esters which are regioselectively substituted at the C2 position and which are particularly preferred according to the invention are esters of starch or starch derivatives, particularly hydroxyethylstarch or hydroxypropylstarch. The present invention also relates to esters, which are regioselectively substituted at the C2 position, of cellulose, cellulose esters or cellulose ethers, particularly of hydroxyethyl cellulose, methyl cellulose, pullulan or maltose. The oligo- and polysaccharide esters according to the invention are obtainable by reaction with esterification reagents from the group comprising vinyl esters, carboxylic anhydrides and trihalogenoethyl esters, as well as lactones, which are described in more detail below in the description of the method. Oligo- and polysaccharide esters which regioselectively substituted at the C2 position and which are particularly preferred according to the invention are 2-O-propionyl-starch, 2-O-butyrylstarch, 2-O-benzoylstarch, 2-O-laurylstarch, 2-O-methoxy-carbonylstarch, 2-O-acryloylstarch and 2-O-methacryloylstarch, most preferably 2-O-acetylstarch. According to the invention, the oligo- and polysaccharides which are regioselectively substituted at the C2 position can be esterified at the remaining OH groups of the AGU with other ester groups which are not identical to the ester groups at the C2 position.
The present invention further relates to a method of producing the compounds according to the invention in the presence of an organic solvent, which method is catalysed by enzyme or salt and is carried out on a dissolved or highly swollen oligo- or polysaccharide.
DETAILED DESCRIPTION OF THE INVENTION
Starting from the disadvantages of the known methods which were described above, e.g. low yields of product and low degrees of regioselectivity, it has thus proved possible, using catalysis by means of enzymes, to effect the esterification of oligo- and polysaccharides, which are dissolved in organic solvents or which are strongly swollen, regioselectively at the secondary hydroxyl group of the C2 position, and has also proved possible to effect said esterification in combination with the esterification of the primary hydroxyl group of the C6 position of the AGU. The method results in very high product yields, and the partial degrees of substitution can be varied and adjusted over wide limits. Particularly high regioselectivities are achieved with oligo- and polysaccharides which comprise an α-(1,4)-glycoside linkage, particularly starch. However, the method can also be applied to oligo- and polysaccharides which comprise a β-(1,4)-glycoside linkage. Organic solvents which are suitable in principle are those in which the oligo- and polysaccharides which are used exhibit considerable swelling or dissolve, and in which the enzymes used exhibit satisfactory activity. Polar organic solvents such as Dimethyl sulphoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), pyridine and N-methylmorpholine-N-oxide (NMMO) can therefore be used as solvents, as can mixtures of the aforementioned solvents. DMSO is preferred. The enzymes surprisingly exhibit high activity, particularly in DMSO, and products which are esterified strictly regioselectively are obtained in a single-stage reaction. These esters can be converted into regioselectively substituted mixed derivatives, such as esters and ethers, by subsequent, selective reactions.
The esterification can be carried out on polysaccharides, preferably on starch from various natural sources and with wide range of amylose contents and molecular weights, and on starch derivatives, particularly hydroxyethylstarches or hydroxy-propylstarches, and can also be carried out on cellulose, cellulose derivatives, pullulan, pullulan derivatives and oligosaccharides.
Proteases of all types can be used as enzymes. The preferred proteases are serine-, cysteine-, asparagine- and metalloproteases. The proteases are preferably dissolved in a phosphate buffer, or alternatively in a carbonate buffer, within a pH range of 4-9 depending on the enzyme, preferably at pH 7-8, and are subsequently lyophilised. The preferred proteases are proteinase N and subtilisin of Bacillus subtilis, proteinase 2A of Aspergillus oryzae, proteinase 6 of Aspergillus sp., a-chymotrypsin, papain, renin and thermolysin.
Esters of general formula
are preferably used as esterification reagents, wherein R 2 preferably denotes a saturated or unsaturated alkyl group comprising 2 to 6 C atoms, or an unsaturated or saturated, branched or unbranched trihalogenoalkane radical comprising 2 to 4 C atoms, particularly vinyl, trihalogenoethyl or alkyl. R 1 is preferably an alkyl group comprising 2-18 C atoms, which can be saturated, unsaturated, straight-chain, branched or cyclic and which can optionally be substituted, or an aryl group (which is optionally substituted). R 1 is most preferably selected from the group comprising acetyl, propyl, butyryl, vinyl, methacryl, cinnamoyl, pivaloyl and cyclohexyl. When esters of alkenoic acids are used, the double bonds can also be utilised for polymerisation in order to build up network structures. This option also exists when using esters of dicarboxylic acids comprising the R 2 radical, such as vinyl adipate, wherein crosslinking can be effected uniformly in the special polysaccharide.
Esterification reagents which are particularly suitable include vinyl acetate, vinyl propionate, vinyl laurate, vinyl butanoate, vinyl stearate, vinyl benzoate, vinyl acrylate, vinyl methacrylate, vinyl crotonate, vinyl pivalate and divinyl pivalate.
Other esterification reagents include carboxylic anhydrides, preferably acetic anhy-dride, propionic anhydride, succinic anhydride and itaconic anhydride, as well as reactive lactones, preferably propiolactone and a-angelicalactone. In the case of carboxylic anhydrides, substitution also occurs at the C6 position of the AGU as well as at the C2 position.
N-isopropylidene compounds of general formula
can also be used as esterification reagents, whereupon the corresponding carboxylic acid esters of the oligo- and polysaccharides are formed. R 1 is preferably an alkyl group comprising 2-18 C atoms, which can be saturated, unsaturated, straight-chain, branched or cyclic and which is optionally substituted, or can be an aryl group (which is optionally substituted). R 1 is most preferably selected from the group comprising acetyl, propyl, butyryl, vinyl, methacryl, cinnarnoyl, pivaloyl and cyclohexyl.
Particularly suitable esterification reagents from the group comprising N-isopropylidene compounds include N-isopropylidene-O-methyl carbonate, N-isopropylidene-O-ethyl carbonate and N-isopropylidene-O-benzyl carbonate.
The method according to the invention is characterised in that the substrate is dissolved in a polar organic solvent—which is DMSO in the case of starch—to which the enzyme and the transesterification reagent are added, and is subsequently incubated. The incubation temperature is between 20° C. and 85° C., and is preferably within the range from 20 to 45° C., particularly in the interval from 35 to 45° C. The times of reaction range from 2 to 100 hours, whereupon a conversion of about 50% is achieved with respect to the acylating reagent. Alternatively, the transesterification reagent can be activated by the enzyme in a preceding step. After the reaction is complete, the enzyme is separated by liquid-solid separation (e.g. centrifugation, filtration). The product is isolated by precipitation and is washed and dried. The solvents which remain can be worked-up by distillation and can subsequently be recycled to the esterification process. The enzyme can thus be used in a cyclic process without loss of activity.
When the reaction in the aforementioned system is conducted at a temperature of 40° C., chemical esterification also occurs in addition to enzyme-catalysed esterification. This chemical esterification occurs with the production of degrees of substitution ranging from a few percent up to a maximum total degree of substitution corresponding to AS=0.25. This results in the esterification of other hydroxyl groups which are present in the molecule. This chemical esterification can be substantially suppressed if the reaction is conducted at lower temperatures (20-25° C.), or is preferably suppressed by conducting the reaction in systems which are almost anhydrous (water content <0.01%).
A partial degree of substitution of up to AS=1.0 at the C2 position of the AGU can be achieved in oligo- and polysaccharides by the method according to the invention. Any desired partial AS≦1.0 at the C2 position of the AGU can be achieved via the molar equivalents of acylating reagent which are used (Table 1).
TABLE 1
Molar equivalents of vinyl acetate and AS acetate values which
can be achieved during the production of 2-O-acetylstarch with
proteinase N in DMSO at 39° C. and at a time
of reaction of 70 hours.
Molar equivalents vinyl acetate
0.5
1.0
1.5
2.3
4.0
AS acetate
0.3
0.5
0.7
1.0
1.1
The partial AS in the C2 position of the AGU can also be adjusted via the reaction kinetics as well as via the molar equivalents, i.e. desired AS values ≦1.0 can be achieved depending on the time at which the reaction is stopped (Table 2).
TABLE 2
Time of reaction and AS acetate values which can be achieved during
the production of 2-O-acetylstarch with proteinase N in DMSO at
39° C. and 2.3 molar equivalents of vinyl acetate.
Time of reaction (hours)
2
5
10
20
30
70
AS acetate
0.1
0.3
0.5
0.8
0.9
1.0
Verification of the regioselectivity of the enzymatically catalysed esterification reaction was effected on the intact oligo- or polysaccharide by one- and multi-dimensional NMR spectrometry. For this purpose, the remaining free hydroxyl groups were esterified with a suitable carboxylic anhydride, for example with propionic anhydride for saccharide acetates or with acetic anhydride for saccharide benzoates or for other saccharide acylates. These mixed esters are soluble in chloro-form and can be investigated by NMR spectrometry. After evaluating the signals of the AGU protons as hydrocarbons via 1 H/ 1 H and 1 H/ 13 C correlation, the corresponding acyl groups can be assigned to their position on the AGU with the aid of a 1 H/ 13 C multiple bond correlation which is detected using 1 H (HMBC technique) (Carbohydr. Res. 224 (1992), 277-283).
In a variant of the method according to the invention, production is effected catalysed by salts only, without further addition of enzyme. Degress of substitution <1.0 at the C2 position are thereby achieved.
As distinct from enzyme catalysis, regioselectivity here is controlled via the state of dissolution of the oligo- and polysaccharides in a polar organic solvent, preferably in DMSO. Interactions between the solvents and the AGU components increase the acidity of the proton of the hydroxyl group in the C2 position of the AGU (J. Am. Chem. Soc. 98 (1976), 4386). By employing a suitable salt as a catalyst, complete esterification of this position can then be effected, wherein it is possible either to employ reaction kinetics control or to control the reaction via the type and amount of catalyst (table 3). The salt is usually present in a concentration of 1-10% by weight, preferably 2-5% by weight, with respect to the starting material.
TABLE 3
Dependence of the regioselectivity of acetylation of starch
(Hylon VII) by vinyl acetate (2.3 molar equivalents) on the
time of reaction and on the type and amount of catalyst
Time of reaction
Catalyst
Starch acidity
(hours)
Type
Amount (mol %) 1
AS total 2*
AS C2 2**
5
Na 2 HPO 4
10
0.52
0.52
5
Na 2 HPO 4
50
0.92
0.92
5
Na 2 HPO 4
100
0.95
0.95
70
Na 2 HPO 4
5
1.00
1.00
4
Na 2 CO 3
10
0.45
0.45
4
Na 2 CO 3
20
0.95
0.95
4
Na 2 CO 3
50
1.51
0.90
0.5
K 2 CO 3
10
0.70
0.70
1
K 2 CO 3
10
1.40
0.90
1 with respect to the starch medium used.
2* AS total refers to total degree of substitution
3** AS C2 refers to degree of substitution for the C2 position
The method results in higher product yields, and the partial degree of substitution can be adjusted in a defined manner. Suitable solvents for carrying out the method include dimethylsulphoxide (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethyl-acetamide (DMA).
The method can be applied to polysaccharides, preferably to starches with different amylose contents and molecular weights, to starch derivatives such as hydroxy-ethylstarch or hydroxypropylstarch, and to pullulan and pullulan derivatives and oligosaccharides such as cyclodextrin.
Suitable catalysts include salts of inorganic mineral acids, salts of carboxylic acids and carbonates of the alkali and alkaline earth metals. The preferred salts are Na 2 HPO 4 , CaHPO 4 , Na 2 CO 3 , MgCO 3 (NH 4 Cl) 2 CO 3 , Na 2 SO 2 , NH 4 Cl, NaBr, NaCl and LiCl, as well as sodium citrate. In order to suppress esterification at other hydroxyl groups,; e.g. in the C 3 or C 6 position, when using salts of weak acids as catalysts, a maximum of only 10 mol % must be used with respect to the weight of oligo- or polysaceharide to be reacted, and at the same time a defined time of reaction must be adhered to.
Esters of general formula
are preferably used as esterification reagents, wherein R 2 can denote vinyl, trihalogenoethyl or alkyl for example. Examples of R 1 include an alkyl group comprising 2-18 C atoms, which can be saturated, unsaturated, straight-chain, branched or cyclic (and which is optionally substituted), or an aryl group (which is optionally substituted). When esters of alkenoic acids are used, the double bonds can also be utilised for polymerisation in order to build up network structures. This option also exists when using esters of dicarboxylic acids comprising the R 2 radical, such as vinyl adipate, wherein crosslinking can be effected uniformly in the special polysaccharide.
Other esterification reagents include carboxylic anhydrides, for example acetic anhydride, propionic anhydride, succinic anhydride and itaconic anhydride, as well as reactive lactones, preferably propiolactone and a-angelicalactone. In the case of carboxylic anhydrides, substitution also occurs at the C6 position of the AGU as well as at the C2 position.
N-isopropylidene compounds of general formula
can also be used as esterification reagents, wherein the corresponding carboxylic acid esters of the oligo- and polysaccharides are formed. Examples of R 1 include alkyl groups comprising 2-18 C atoms, which can be saturated, unsaturated, straight-chain, branched or cyclic (and which are optionally substituted), and aryl groups (which are optionally substituted).
The method according to the invention is characterised in that oligo- or poly saccharides are regioselectively esterified at the hydroxyl group of position C2 of the anhydroglucose unit by active esters in polar organic solvents—preferably DMSO— using salts as catalysts. The reaction temperature is between 20° C. and 100° C., and is preferably within the range from 30 to 50° C. The times of reaction range from 0.5 to 100 hours, depending on the reaction temperature and on the catalyst used. The catalyst is separated by liquid-solid separation (e.g. centrifugation, filtration). Alternatively, a defined amount of water can also be added to the precipitant, in order to dissolve out the catalyst. The resulting ester is isolated by precipitation and is washed and dried.
The solvents which remain can be worked-up by distillation and can subsequently be recycled to the esterification process.
With the method according to the invention, a partial degree of substitution at the C2 position of the AGU of up to AS=1.0 can be achieved according to choice via the reaction kinetics or via the molar equivalents of transesterification reagent used.
Regioselectivity was verified by means of two-dimensional NMR spectrometry. For this purpose, the acylated polysaccharide had to be completely propionylated in the case of acetates, or acetylated in the case of other polysaccharide esters. In this manner, the substitution site can be unambiguously verified by means of multiple bond correlation (Carbohydr. Res. 224 (1992), 277-283).
The products which are obtained by the method according to the invention, e.g. starch acetates, can be decomposed by amylases. At a suitable molecular weight of the starch and when substitution is effected strictly at the C2 position, starch acetates are suitable as blood plasma expanders. 2-O-acetylstarch is particularly suitable for this application. Therefore, the present invention further relates to the use of 2-O-acetylstarch as a blood plasma expander. Moreover, biodegradable plastics can be synthesised from starch acylates. Membranes having a substantially uniform structure can be synthesised by crosslinking processes. Absorbents for different applications can also be produced by treatment to form further derivatives. Starch acetates which have thermoplastic properties can conceivably be used in the pharmaceutical industry as active ingredient retardants.
Regioselectively substituted cyclodextrin esters can be used in the pharmaceutical industry as carriers for pharmaceutical active ingredients. Furthermore, compounds of high molecular weight can be synthesised, in the manner of copolymers, which could be suitable for chromatography (e.g. for the separation of enantiomers).
EXAMPLES
EXAMPLE 1
40 g starch (Hylon VII, a native maize starch with a high amylose content manufactured by National Starch & Chemical) were heated in 2 litres DMSO to 80° C. until a clear solution was formed. After cooling, 54 ml vinyl acetate and 750 mg proteinase N of Bacillus subtilis were added (the protease was activated by dissolving it in a phosphate buffer pH=7.8; c=0.15 M) and subsequent lyophilisation; the actual amount of enzyme weighed in was therefore 1.5 g). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The 2-O-acetylstarch was filtered off under suction, washed, and finally dried under vacuum. 46 g 2-O-acetylstarch were obtained which had an AS=1.0.
EXAMPLE 2
40 g starch (Hylon VII) were heated in 2 litres DMSO to 80° C. until a clear solution was formed. 54 ml vinyl acetate and 750 mg proteinase N of Bacillus subtilis were added (see Example 1 for the activation of the protease). The mixture was shaken for 20 hours at 80° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The 2-O-acetylstarch was filtered off under suction, washed, and finally dried under vacuum.
46 g 2-O-acetylstarch were obtained which had an AS=1.0.
EXAMPLE 3
2 g b-cyclodextrin (manufactured by Fluka) were dissolved in 20 ml DMSO, and 2.7 ml vinyl acetate and 37 mg proteinase N of Bacillus subtilis were subsequently added (see Example 1 for the activation of the protease). The mixture was shaken for
70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was concentrated, and the product was precipitated, washed, and finally dried under vacuum. 2.1 g heptakis-2-O-acetyl-b-cyclodextrin were obtained.
EXAMPLE 4
2 g b-cyclodextrin were dissolved in 20 ml DMSO, and 2.7 ml vinyl acetate and 37 mg proteinase N of Bacillus subtilis were subsequently added (see Example 1 for the activation of the protease). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was concentrated, and the product was precipitated, washed, and finally dried under vacuum. 2.1 g heptakis-2-O-acetyl-b-cyclodextrin were obtained.
EXAMPLE 5
2 g starch (Hylon VII) were heated in 40 ml DMSO to 80° C. until a clear solution was formed. After cooling, 12.5 g 2,2,2-trichloroethyl acetate and 37 mg proteinase N of Bacillus subtilis were added (see Example 1 for the activation of the protease). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The 2-O-acetylstarch was filtered off under suction, washed, and finally dried under vacuum.
2.0 g 2-O-acetylstarch were obtained which had an AS=0.4.
EXAMPLE 6
2 g starch (Hylon VII) were heated in 40 ml DMSO to 80° C. until a clear solution was formed. After cooling, 1.9 g N-isopropylidene-O-methyl carbonate and 37 mg proteinase N of Bacillus subtilis were added (see Example 1 for the activation of the protease). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The starch derivative was filtered off under suction, washed, and finally dried under vacuum.
2.0 g 2-O-methoxycarbonylstarch were obtained which had an AS=0.4.
EXAMPLE 7
2 g starch (Hylon VlI) were heated in 40 ml DMSO to 80° C. until a clear solution was formed. After cooling, 2.7 ml vinyl acetate and 37 mg thermolysin were added (see Example 1 for the activation of the protease). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The acetylstarch was filtered off under suction, washed, and finally dried under vacuum.
2.4 g 2,6O-diacetylstarch were obtained which had an AS=1.0 at the C2 position and an AS=0.4 at the C6 position.
EXAMPLE 8
2 g starch (Hylon VII) were heated in 40 ml DMSO to 80° C. until a clear solution was formed. After cooling, 2.7 ml acetic anhydride and 37 mg proteinase N of Bacillus subtilis were added (see Example 1 for the activation of the protease). The mixture was shaken for 70 hours at 39° C. After removing the enzyme by centrifugation, the clear centrifugate was precipitated. The acetylstarch was filtered off under suction, washed, and finally dried under vacuum.
2.0 g acetylstarch were obtained which had an AS=0.7 at the C2 and C6 positions of the AGU.
EXAMPLE 9
0.3 g of enzymatically produced starch acetate (Example 1) was suspended in 5 ml pyridine. 0.1 g dimethylaminopyridine (DMAP) and 5 ml propionic anhydride were added to this suspension, which was stirred for 20 hours at 90° C. The propionylated starch acetate was precipitated in ethanol, intensively washed with ethanol and dried under vacuum. A completely substituted 2-O-acetyl-3,6-O-dipropionylstarch was obtained.
The dried product exhibited no OH valency vibrations in the 3200-3600 cm −1 IR range and was soluble in chloroform, which resulted in the following NMR data:
AGU: d=5.22(H1), 4.72(H2), 5.36(H3), 3.91-3.95(H4,H5), 4.53(H6), 4.24(H6′)
propionyl at position 6: d=1.18(CH 3 ), 2.45(CH 2 )
propionyl at position 3: d=1.05(CH 3 ), 2.20(CH 2 )
acetyl at position 2: d=1.98(CH 3 )
(Bruker DRX 400 NMR spectrometer, 323 K)
EXAMPLE 10
2 g cellulose, dissolved in N-methyl-morpholine-N-oxide (NMMNO), were diluted with DMSO (ratio by volume: VDMSO:VNMMO=1:1). 2.7 ml vinyl acetate and 37 mg proteinase N of Bacillus subtilis (see Example 1 for the activation of the protease) were subsequently added to the cellulose solution. This mixture was shaken at a temperature of T=80° C. for a period of 24 hours. After precipitating the product in hot water, it was repeatedly washed with water and finally dried under vacuum. 1.2 g acetyl cellulose were obtained which had an AS of 0.3.
EXAMPLE 11
106 g starch (Hylon VII, a native maize starch with a high amylose content, manufactured by National Starch & Chemical) were dissolved in 1 litre DMSO at 80° C. After cooling to 40° C. 140 ml vinyl acetate and 5 g Na 2 HPO 4 were slowly added. The mixture was stirred for 70 hours and the insoluble Na 2 HPO 4 was removed by centrifugation. The product was precipitated in ethanol, filtered under suction, washed and dried under vacuum. 116 g 2-O-acetylstarch was obtained which had an AS=1.0.
EXAMPLE 12
106 g starch (Hylon VII, a native maize starch with a high amylose content, manufactured by National Starch & Chemical) were dissolved in 1 litre DMSO at 80° C. After cooling to 40° C. 63 ml vinyl acetate and 5 g Na 2 HPO 4 were slowly added. The mixture was stirred for 70 hours and the insoluble Na 2 HPO 4 was removed by centrifugation. The product was precipitated in ethanol, filtered under suction, washed and dried under vacuum.
102 g 2-O-acetylstarch was obtained which had an AS=0.7.
EXAMPLE 13
2 g β-cyclodextrin (manufactured by Fluka) were dissolved in 20 ml DMSO, and 2.7 ml vinyl acetate and 20 mg Na 2 HPO 4 were subsequently added. The mixture was stirred for 70 hours at 40° C. After removing the inorganic salt by centrifugation, the centrifugate was concentrated and the product was precipitated in ethanol, washed and dried under vacuum. 2.1 g heptakis-2-O-acetylstarch were obtained.
EXAMPLE 14
2 g dextrin 20 (manufactured by Fluka) were dissolved in 40 ml DMSO at 80° C. and 2.7 ml vinyl acetate and 20 mg Na 2 HPO 4 were subsequently added. The mixture was stirred for 70 hours at 40° C. After removing the inorganic salt by centrifugation, the centrifugate was concentrated and the product was precipitated in ethanol, washed and dried under vacuum. 2 g 2-O-acetyldextrin were obtained, which had an AS 1.0.
EXAMPLE 15
2 g starch (Hylon VII, a native maize starch with a high amylose content, manufactured by National Starch & Chemical) were dissolved in 40 ml DMSO at 80° C. After cooling to 40° C. 2.7 ml vinyl acetate and 20 mg NaCl were slowly added. The mixture was stirred for 70 hours and the insoluble NaCl was removed by centrifugation. The product was precipitated in ethanol, filtered under suction, washed and dried under vacuum. 2.1 g 2-O-acetylstarch was obtained which had an AS=1.0.
EXAMPLE 16
2 g starch (Hylon VII, a native maize starch with a high amylose content, manufactured by National Starch & Chemical) were dissolved in 40 ml DMSO at 80° C. After cooling to 40° C. 2.7 ml vinyl acetate and 20 mg Na 2 CO 3 were slowly added. The mixture was stirred for 70 hours and the insoluble Na 2 CO 3 was removed by centrifugation. The product was precipitated in ethanol, filtered under suction, washed and dried under vacuum. 2.1 g 2-O-acetylstarch was obtained which had an AS=1.0. | A regioselectively substituted member selected from the group consisting of oligo-saccharide ester and polysaccharide ester is disclosed. The ester has a partial average degree of substitution AS at the C2 position of its anhydroglucose unit of at least 90% relative to the total AS. Also disclosed is a method of producing the regioselectively substituted ester. The method entails reacting in the presence of a catalyst a dissolved or a highly swollen oligo-saccharide or polysaccharide with an esterification reagent. | 2 |
FIELD OF THE INVENTION
The present invention relates to a method and/or apparatus for implementing controllers generally and, more particularly, to a method and/or apparatus for implementing enhanced device identification in a controller.
BACKGROUND OF THE INVENTION
Conventional protocol controllers often implement some form of software device identification. For example, the Peripheral Connect Interface (PCI) bus protocol provides two 16-bit identification fields called Vendor ID and Device ID. Software drivers access these fields to identify which hardware devices to control.
In a conventional protocol chip, the identification fields are hardwired. The conventional methodology calls for the identification fields to be updated any time a functional change is made to the chip. Updating the fields each time a functional change is made can potentially cause a problem because the functional change can involve mask layers that are not used for generating the identification information.
It would be desirable to implement identification fields that may be updated by software.
SUMMARY OF THE INVENTION
The present invention concerns an apparatus comprising a first circuit, a second circuit and a third circuit. The first circuit may be configured to present device information in response to one or more externally generated signals. The second circuit may be configured to store the device information. The third circuit may have (i) a first mode configured to program the device information into the second circuit and (ii) a second mode configured to transfer the device information from the second circuit to the first circuit.
The objects, features and advantages of the present invention include providing a method and/or apparatus for implementing enhanced device identification that may (i) implement identification fields that can be updated by software, (ii) provide on chip memory and firmware for updating and storing start of day (SOD) information and device identification fields, (iii) allow changes in identification fields without costly mask changes, (iv) replace or eliminate external devices for updating internal identifiers and/or (v) allow firmware to internally store permanent and semi-permanent information at any time.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of the present invention will be apparent from the following detailed description and the appended claims and drawings in which:
FIG. 1 is a block diagram of a preferred embodiment of the present invention;
FIG. 2 is a more detailed block diagram of a preferred embodiment of the present invention; and
FIG. 3 is a flow diagram of an example operation in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , a block diagram of a circuit 100 is shown in accordance with a preferred embodiment of the present invention. The circuit 100 is generally implemented as a single integrated circuit (or chip). The circuit 100 may be implemented, in one example, as a protocol controller. The circuit 100 generally comprises a block (or circuit) 102 , a block (or circuit) 104 , and a block (or circuit) 106 . The circuit 102 may be implemented as an on-chip storage device. The circuit 102 may comprise, in one example, a non-volatile memory (e.g., EEPROM, NVRAM, etc.). However, other types of memory may be implemented accordingly to meet the design criteria of a particular implementation. The circuit 102 generally replaces external devices (e.g., external EEPROM that are read at power-up) that are used in conventional approaches to update internal identifiers (e.g., start of day (SOD) information).
The circuit 104 may comprise firmware that may be configured to update, in one example, one or more device identification fields of the circuit 100 . The device identification fields are generally updated with information contained within the memory 102 . Such updating may allow changes to be made in the identification fields of the device 100 without costly mask changes to the IC device. The circuit 104 may also be configured to program (or update) information stored in the memory 102 . For example, the circuit 104 may comprise firmware (i) containing the SOD information and/or register values and (ii) configured to program the SOD information and/or register values into the circuit 102 . Alternatively, the firmware may be configured to accept SOD information and/or register values from external to the circuit 100 (e.g., from a host). The firmware may be further configured to store permanent and semi-permanent information in addition to the SOD information and register values in the memory 102 .
The circuit 106 may be implemented, in one example, as one or more host accessible registers. The circuit 106 may be configured to present device identifiers in response to a request from the host (e.g., a request generated by a software driver). In one example, the circuit 104 may be configured to update (or program) the device identifiers in the circuit 106 from information stored in the memory 102 . In another example, the circuit 106 may be configured to retrieve device identifiers from the circuit 102 and present the retrieved identifiers to the host.
Referring to FIG. 2 , a more detailed block diagram of the circuit 100 of FIG. 1 is shown. In one example, the circuits 102 , 104 and 106 may be coupled by an internal bus 108 . The internal bus 108 may be implemented, in one example, as an AHB bus. However, other appropriate busses may be implemented accordingly to meet the design criteria of a particular application. In one example, the circuit 102 may be coupled to the bus 108 via a circuit 110 . The circuit 110 may be implemented, in one example, as an AHB slave device. The circuit 104 may be implemented, in one example, as an AHB master device. However, other types of devices may be implemented accordingly to meet the design criteria of a particular application.
The circuit 104 (e.g., the master device) generally communicates with the circuit 110 (e.g., the slave device) to store information in and/or retrieve information from the memory 102 . When the information is retrieved, the circuit 104 or the circuit 110 may be configured to route the information to the circuit 106 via the bus 108 . The circuit 106 may be configured to present the retrieved information to a host device 112 via, in one example, an interface 114 . The interface 114 may be implemented, in one example, as a PCI interface. However, other types of interfaces may be implemented accordingly to meet the design criteria of a particular application.
Referring to FIG. 3 , a flow diagram 200 is shown illustrating an example operation in accordance with a preferred embodiment of the present invention. Following power-on of a device incorporating the present invention (e.g., the block 202 ), communication with the host device may be suspended. For example, a boot mechanism of the device 100 may be disabled (e.g., the block 204 ). In general, the boot mechanism may be disabled to allow time for initialization of the device 100 . For example, start of day (SOD) information and/or device identifiers of the device 100 may be initialized from the internal memory 102 (e.g., the block 204 ).
In one example, the circuit 102 may comprise an on-chip, non-volatile storage media with one or more flags. The one or more flags may be configured to indicate whether the circuit 102 has been programmed with SOD information and/or device identifiers. Firmware may be configured to check the flags (e.g., the block 206 ). When the flags are in a first state (e.g., not set), the firmware may be configured to program SOD information and internal register values (e.g., device identifiers) into the circuit 102 via the internal data bus 108 (e.g., the block 208 ). The SOD information and internal register values to be programmed may be contained, in one example, within the firmware. Alternatively, the firmware may be configured to accept the information from the host driver. When the flags are in a second state (e.g., set), the firmware may be configured to read the register values from the circuit 102 and program SOD information and/or registers of the chip 100 (e.g., the block 210 ). Once the start of day information and/or registers have been initialized (or updated), the boot mechanism may be enabled (e.g., the block 212 ).
The various signals of the present invention are generally “on” (e.g., a digital HIGH, or 1) or “off” (e.g., a digital LOW, or 0). However, the particular polarities of the on (e.g., asserted or set) and off (e.g., de-asserted or not set) states of the signals may be adjusted (e.g., reversed) accordingly to meet the design criteria of a particular implementation. Additionally, inverters may be added to change a particular polarity of the signals.
The function performed by the flow diagram of FIG. 3 may be implemented using a conventional general purpose digital computer programmed according to the teachings of the present specification, as will be apparent to those skilled in the relevant art(s). Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will also be apparent to those skilled in the relevant art(s).
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. | An apparatus comprising a first circuit, a second circuit and a third circuit. The first circuit may be configured to present device information in response to one or more externally generated signals. The second circuit may be configured to store the device information. The third circuit may have (i) a first mode configured to program the device information into the second circuit and (ii) a second mode configured to transfer the device information from the second circuit to the first circuit. | 6 |
[0001] This application claims the benefit of the Patent Korean Application No. P2004-91274, filed on Nov. 10, 2004, which is hereby incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a combination dryer, and more particularly, to an operation method for a combination dryer which enables air in a drying drum and a cabinet for drying the laundry to circulate continuously and enables condensed water generated in the circulation process to perform a refreshing cycle by using the water.
[0004] 2. Discussion of the Related Art
[0005] In general, a dryer is an electric home appliance which can dry cloth items, cloths and beddings (hereinafter, ‘the laundry’). The dryer dries the laundry by supplying hot air to the washed laundry continuously.
[0006] FIG. 1 illustrates a conventional tumble dryer of a related art dryer.
[0007] That is, the related art tumble dryer includes a body 10 , a drying drum 20 , a door 40 , a motor 50 , a drying heater 60 and a fan 70 .
[0008] The body 10 defines an exterior of the tumble dyer, and the drying drum 20 is rotatably mounted inside of the body 10 .
[0009] Also, an opening 11 is formed in front of the body 10 , and the door 40 is coupled for opening/closing the opening 11 .
[0010] The motor 50 is secured to an inner downside of the body 10 for creating a driving force to rotate the drying drum 20 and the fan 70 .
[0011] The drying heater 60 is mounted on an inner portion of a hot air supply channel 81 for heating air flowing within the hot air supply channel 81 . The hot air supply channel 81 guides a hot air passage supplied into the drying drum 20 .
[0012] The fan 70 discharges dry air flowing inside of the drying drum 10 outside, and is provided in communication with a hot air discharge channel 82 .
[0013] Thus, once the fan 70 is put into operation, external air is guided by the hot air supply channel 81 and heated by passing through the drying heater 60 to be drawn into the drying drum 10 .
[0014] Thereby, the damp laundry introduced into the drying drum 10 is getting dried by the heated external air gradually.
[0015] The air having dried the laundry by being circulated within the drying drum 10 is guided by the hot air supplying channel 82 to be discharged outside.
[0016] Once drying is completed by the repeated performance of the above process, the fane 70 and the drying heater 60 are stopped to finish a drying cycle.
[0017] However, the related art tumble dryer has a problem that drying for a tangled portion of the laundry is not dried smoothly, because the drying cycle is in process in a state of the laundry being introduced together at one time.
[0018] There is another problem that it is impossible to keep the laundry for a long time in the related art tumble dryer.
[0019] Thus, recently demands have been increasing accordingly for a new type of a combination dryer having a drying capacity thereof enlarged as well as capable of keeping the laundry for a long time. There are various combination dryers provided with tumble dryers having auxiliary cabinet dryers provided therewith, for example, U.S. Patent No. 2004-0194339 A1 or U.S. Patent No. 2004-0154194.
[0020] The above combination dryer allows a cabinet dryer provided on a top of a conventional dryer having a rotatory drum. The cabinet dryer has space for the laundry and receives hot air used to dry or keep the laundry for a long time.
[0021] However, the combination dryer described above has an inconvenience that a user should directly supply water needed for steam generation to refresh the laundry by using steam.
[0022] Especially, since a refreshing process may be performed even in lack of the water needed for the steam generation, a problem may be caused that the refreshing process is not performed smoothly.
SUMMARY OF THE INVENTION
[0023] Accordingly, the present invention is directed to an operating method for a combination dryer that substantially obviates one or more problems due to limitations and disadvantages of the related art.
[0024] An object of the present invention is to provide an operating method for a combination dryer that enables air for drying in a drying drum of a tumble dryer and a space of a cabinet dryer to be circulated continuously, such that water is generated in the circulation process to perform a refreshing cycle.
[0025] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
[0026] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an operation method for a combination dryer comprises a controlling process for alternatively operating a drying cycle for drying the laundry and a refreshing cycle for refreshing the laundry, wherein the refreshing cycle comprises a step of supplying water for supplying water stored in a water storing chamber into a heating part; a step of generating steam for generating steam by evaporating the water within the heating part; and a step of supplying steam for supplying the steam into a drying drum of a tumble dryer and/or a laundry-keeping space of a cabinet dryer.
[0027] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
[0029] FIG. 1 is a diagram illustrating an inner structure of a conventional tumble dryer.
[0030] FIG. 2 is a diagram schematically illustrating an exterior of a combination dryer according to the present invention.
[0031] FIG. 3 is a block diagram schematically illustrating the combination dryer according to the present.
[0032] FIG. 4 is a flow chart schematically illustrating a controlling process when operating a refreshing cycle in the combination dryer according to the present invention.
[0033] FIG. 5 is a flow chart schematically illustrating a controlling process during the operation of the refreshing cycle.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
[0035] As shown in FIGS. 2 and 3 , a combination dryer according to an embodiment of the present invention includes a tumble dryer 100 , a cabinet dryer 200 , and a control part 300 .
[0036] The tumble dryer 100 performs only a drying cycle of the laundry.
[0037] The tumble dryer 100 includes a drying drum 110 capable of rotating and agitating, a hot air supplying pipe, a hot air supplying part 130 , and an air condensing part 140 .
[0038] The hot air supplying pipe as a pipe guiding a flow of high-temperature hot air is connectedly in communication with inside space among the drying drum 110 , the air condensing part 140 and a cabinet dryer 200 .
[0039] The hot air supplying pipe includes a first supplying pipe 121 for supplying hot air into the drying drum 110 , a second supplying pipe 122 for receiving and supplying the air having passed through the air condensing part 140 to the first supplying pipe 121 , and a third supplying pipe 123 for receiving and transmitting the air discharged from the drying drum 110 to the air condensing part 140 .
[0040] A filtering part 124 may be further provided in the third supplying pipe 123 for filtering foreign substances contained in the flowing air.
[0041] Also, the hot air supplying part 130 is provided in the second supplying pipe 122 for generating hot air.
[0042] The hot air supplying part 130 includes a drying heater 131 for heating the air flowing inside of the second supplying pipe 122 , a fan 132 for forcibly ventilating the air within the second supplying pipe 122 .
[0043] Preferably, the fan 132 is provided in a portion of the second supplying pipe 12 allowing air drawn into the drying heater 131 .
[0044] That is for minimizing damage of the fan 132 due to hot air.
[0045] Also, the air condensing part 140 condenses the air flowing along the hot air supplying pipe to radiate heat of the air.
[0046] The air condensing part 140 includes a condenser 141 and a condensing fan 142 .
[0047] The condenser 141 receives the hot air from the third supplying pipe 123 , and includes a pipe having a plurality of branched portions and a cooling pin.
[0048] The condensing fan 142 ventilates external air toward the condenser 141 .
[0049] Furthermore, a water holding chamber 150 is further provided in the air condensing part 140 . The water holding chamber 150 is connected with the air condensing part 140 , the cabinet dryer 200 and a drain pipe 160 .
[0050] The water holding chamber 150 holds condensed water generated in the air condensing part 140 and remaining washing water generated within the space for keeping the laundry in the cabinet dryer 200 . Alternatively, a user may directly supply water to the water holding chamber 150 .
[0051] Furthermore, a pump 161 is further provided in the drain pipe 160 for transmitting the water to the water holding chamber 150 after pumping the water forcibly.
[0052] Preferably, a water level sensor 151 is further provided in the water holding chamber 150 for sensing a level of the water stored in the water holding chamber 150 .
[0053] The cabinet dryer 200 is mounted on a top of the tumble dryer 100 , with a predetermined space having lots of the laundry kept therein.
[0054] The cabinet dryer 200 includes space 220 for keeping the laundry therein, a hot air inlet pipe 241 , and an air outlet pipe 242 .
[0055] A first end of the hot air inlet pipe 241 is connected to a portion of the second supplying pipe 122 where air is discharged, and a second end thereof is connectedly in communication with the space 220 keeping the laundry therein for transmitting the hot air from the second supplying pipe 122 into the space 220 keeping the laundry therein.
[0056] Preferably, an air channel valve 125 may be further provide in the second supplying pipe 122 for choosing and guiding a direction of the air flowing to the first supplying pip 2 121 and/or the hot air inlet pipe 241 .
[0057] Also, a first end of the air outlet pipe 242 is in communication with the space 220 keeping the laundry therein, and a second end thereof is connected to the third supplying pipe 123 to discharge the high-temperature humid air having passed through the laundry within the space 220 .
[0058] At that time, an auxiliary exhaustion fan (not shown) may be further provided in the air outlet pipe 242 .
[0059] On the other hand, the combination dryer according to the embodiment of the present invention further includes a steam generating part 410 for generating steam after receiving the water stored in the water holding chamber 150 , and a steam supplying pipe 420 for supplying the steam generated in the steam generating part 410 to the cabinet dryer 200 .
[0060] The steam generating part 410 is provided in either of the tumble dryer 100 and the cabinet dryer 200 .
[0061] The steam generating part 410 includes a water supplying pipe 412 for receiving the water from the water holding chamber 150 , a heating part 413 having space for temporally holding the water from the water supplying pipe 412 , and a heating element 414 provided within the heating part 413 for heating the stored water into steam.
[0062] Preferably, an opening/closing valve 415 may be further provided for alternatively opening or closing the inflow of the water supplied to the heating part 413 .
[0063] The control part 300 according to the present invention controls operation of the tumble dryer 100 and the cabinet dryer 200 .
[0064] At that time, the control part 300 may be provided in at least one of the tumble dryer 100 and the cabinet dryer 200 , and it is preferred but not necessary that the control part 300 is provided only in the tumble dryer as shown in the embodiment of the present invention.
[0065] If the control part 300 is provided in both the tumble dryer 100 and the cabinet dryer 200 , the control parts 300 are connected by a data cable (not shown) to make possible to intercommunicate information.
[0066] Also, the control part 300 may control the tumble dryer 100 and the cabinet dryer 200 respectively, and may control the tumble dryer 100 and the cabinet dryer 200 to communicate each other.
[0067] The combination dryer with the configuration described above may operate a refreshing cycle for refreshing the laundry, as well as a drying cycle.
[0068] At that time, the refreshing cycle makes the dried laundry in a state before getting dressed such as smoothing out the wrinkles, and is operated by using a high-temperature steam.
[0069] According to the embodiment of the present invention, the refreshing cycle is operated only in the cabinet dryer 200 .
[0070] Alternatively, the refreshing cycle may be operated in the tumble dryer. But since there is a lots of the laundry tangled in the tumble dryer 100 , the outstanding effect of the refreshing cycle is not expected. If a rack is further provide for holding the laundry after separating the laundry and the refreshing cycle is operated in the tumble dryer 100 , the refreshing effect may be expected.
[0071] It is a distinguishable outstanding technical feature of the present invention that water used for generating steam is created in the combination dryer itself, unlike the related art in that the user supplies extra water for generating steam.
[0072] That is, the water stored within the water holding chamber 150 is used for the water needed to generate steam.
[0073] Since a lot of water is created in the air condensing part 140 of the combination dryer according to the present invention and also there is a lot of water within the space keeping the laundry therein, the water is supplied enough to generate steam.
[0074] Referring to FIG. 4 , an embodiment for a refreshing cycle of the combination dryer according to the present invention will be described.
[0075] First, for the refreshing cycle, a sufficient amount of water is stored in the water storing chamber (S 111 ).
[0076] At that time, the water may be stored during the drying cycle after receiving the washing water remaining in the drying drum 110 of the tumble dryer 100 and/or the space keeping the laundry in the cabinet dryer 200 . Alternatively, the water is stored after receiving the condensed water created by condensing the high-temperature hot air having passed through the air condensing part.
[0077] The drying cycle is a series of processes drying the laundry in the drying drum 110 and/or the space 220 keeping the laundry therein by supplying high-temperature dry air into the drying drum 110 and/or the space 220 through the drying heater 131 and the fan 132 .
[0078] At that time, the dry air supplied into the drying drum 110 and/or the space 220 is reaching at high temperatures by the drying heater 131 , and flown along each supplying pipe 121 , 122 and 123 by the fan 132 . Hence, in the middle of passing through the air condensing part 140 , the dry air is heat-exchanged and condensed in the condenser 141 by the condensing fan 142 to be dried.
[0079] Alternatively, the water may be stored during the refreshing cycle after receiving the water created in the drying drum 110 of the tumble dryer 100 and/or the space 220 of the cabinet dryer 200 .
[0080] As described above, once the refreshing cycle is required to be operated in a state of a sufficient amount of water being stored in the water storing chamber 150 , the opening/closing valve 413 in the water supplying pipe 412 is opened (S 112 ).
[0081] Thus, the water in the water storing chamber 150 is supplied to the heating part 413 through the water supplying pipe 412 .
[0082] If the refreshing cycle is not required to be operated, only a series of the processes storing the water in the water storing chamber 150 is continuously repeated.
[0083] Hence, the control part 300 controls the heating element 414 provided in the heating part 413 to radiate heat (S 113 ).
[0084] Thereby, the water within the heating part 413 turns into vapor to created hot steam.
[0085] The steam is supplied though the steam supplying pipe 420 into the space 220 of the cabinet dryer 200 (s 114 ).
[0086] Thus, due to the hot steam, wrinkles of the laundry are smoothed out and also microorganisms such as various kinds of mold fungi are sterilized.
[0087] As described before, it is preferred but not necessary that the amount of the water stored in the water storing chamber 150 should be always sufficient during the refreshing cycle.
[0088] For that, as shown in a flow chart of FIG. 5 , the control part 300 constantly identifies a water level within the water chamber 150 by controlling the water level sensor 151 during the refreshing cycle (S 121 ). If the water level identified is lower than the water level preset to create steam, a series of processes is performed for generating condensed water.
[0089] Preferably, the above control of the water level sensor 151 and the supplementary process for generating the condensed water is performed at the beginning of the refreshing cycle, that is, before generating the steam, so that the water level may always maintain proper.
[0090] Also, the series of the processes may be processes generating steam by circulating the air into the hot air supplying pipe and condensing the circulated air.
[0091] The air circulation into the hot air supplying pipe is possible through the control of the fan driving. Preferably, heating the drying heater 131 as well as controlling to operate the condensing fan 142 may enable more water to be created.
[0092] In other words, the condensed water needed to create steam is generated by condensing the high temperature hot air after heat-exchanging. At that time, the created condensed water may be supplied to the water storing chamber 150 through controlling of the pump 161 driving (S 123 ).
[0093] As shown in the series of the processes according to the embodiment of the present, it is possible to supply the water needed to create the steam for the refreshing cycle, thereby preventing lack of the water.
[0094] Therefore, the combination dryer according to the embodiment of the present invention has an advantageous industrial effect that the laundry may be sterilized, as well as the wrinkles thereof may be smoothed out, due to the refreshing cycle.
[0095] Especially, since the steam for the refreshing cycle uses the condensed water created in the combination dryer, an inconvenience is removed that the user should identify the water for creating the steam and supply the water.
[0096] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | An operation method for a combination dryer is disclosed. The present invention relates to a combination dryer, and more particularly, to an operation method for a combination dryer which enables air in a drying drum and a cabinet for drying the laundry to circulate continuously and enables condensed water generated in the circulation process to perform a refreshing cycle by using the water. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electric charge detecting apparatus which performs charge-voltage conversion in a charge-coupled device (referred to as a CCD hereinafter).
2. Description of the Prior Art
In a conventional CCD, a signal charge has been detected by a so-called floating diffusion method (depicted as an FD method hereinafter), thereby to generate an output.
More specifically, the potential change has been detected by means of a floating diffusion amplifier by injecting signal charges into a floating diffusion layer according to the floating diffusion method. The floating diffusion amplifier is generally denoted by FDA which is described in "Characterization of Surface Channel CCD" by Marvin H. White, IEEE Journal of Solid-State Circuits, Vol. SC-9, No. 1, 1974, pp. 1-13.
FIGS. 11(a) and 11(b) illustrate the structure of a conventional charge transfer device. FIG. 11(a) is a block diagram of the whole CCD. Photons entering a photodiode PD90 are converted to electric charges and accumulated in PD90. A predetermined time later, the electric charges are read out by a VCCD91 (Vertical CCD) and input to an FDA93 (Floating Diffusion Amp.) through an HCCD92 (Horizontal CCD), and finally detected as a voltage. FIG. 11(b) is a sectional view along A--A' line of FIG. 11(a). HCCD92 in FIG. 11(a) is formed of a P well 81, an n layer 88, n + regions FD83 and RD86, a p - region 89 and a p + layer all laminated on an n-type substrate 80, and polysilicon electrodes on the laminate via a gate oxide film 82. FDA93 is constituted of an FD83 and a source follower amplifier SFA87. The electric charge ΔQ is input from HCCD92 to FD83 through an output gate OG84. Supposing that the parasitic capacitance present between FD83 and SFA87 is represented by C T and the gain of SFA87 is G T , the potential change ΔV is expressed by an expression (1) below:
ΔV=G.sub.T ·Q/C.sub.T ( 1)
A reset pulse synchronized with a φH signal is input to an RG85. A constant voltage V RD is impressed to an RD86. The electric charge ΔQ input to FD83 is discharged to RD86 in accordance with the reset pulse of RG85.
FIG. 12(a) is a plan view of a general MOS transistor, and cross sections thereof along the lines A--A' and B--B' are indicated respectively in FIGS. 12(b) and 12(c). Referring to FIG. 12(b), a field oxide film 206 is a thick film obtained by a local oxidation method of silicon (LOCOS), and generally 0.5-1.0 μm (5000-10000Å) thick. In the transistor of FIG. 12, after a gate 96, a source 94 and a drain 95 are formed, interlayer films of BPSG, NSG or the like (not shown) are laminated, and then contact holes 97, 98 are opened by etching. The source 94 is connected with the drain 95 by an aluminum wiring.
The P + region of the field oxide film 206 undesirably spreads further than in the initial state, as shown in FIG. 12(b), due to the thermal oxidation. Thereby, a capacitance Cb exists between the polysilicon gate 96 and P + region. A gate oxide film 208 is 500-700Å thick, and the field oxide film 206 is 5000-10000Å thick. When the transistor operates, a channel 200 is constructed and therefore, a capacitance C6 is present also between the gate 96 and the channel 200. There is an overlap capacitance C7 between the gate 96 and the channel 200 at the drain side, which will be re-defined as a capacitance Cd. A source capacitance Cs is the sum of an overlap capacitance C5 and the capacitance C6. FIG. 13 is a diagram explanatory of the parasitic capacitance. Although SFA87 is constructed in two stages, only the first stage is shown in the drawing for the convenience of description. The parasitic capacitance is constituted as follows:
C.sub.T =C1+C2+C3+C4+C.sub.Tr ( 2)
C.sub.Tr +Cd+Cs·(1-G1)+Cb (3)
C.sub.L +C.sub.Tr2 +C.sub.dL +C.sub.Js ( 4)
wherein C1 and C2 are capacitances between FD83 and OG84 and between FD83 and RG85, C3 is a capacitance between FD83 and the P well 81, C4 is a capacitance of the wiring from FD83 to the drive transistor Tr in the first stage, G1 is a gain of the source follower in the first stage, and C Tx is an input capacitance from the drive transistor. In other words, the expression (3) represents that the capacitance Cs is lowered by nearly one digit because of the gain G1 (G1, G2=approximately 0.8-0.95), whereby C Tr , C T are decreased. C JS is a capacitance between the diffusion region at the source side of the drive transistor Tr and the P well 81, C dL is a capacitance between a gate and a drain (working also as a source of the drive transistor Tr) of a load transistor Tr, and C L is a load capacitance necessary to be driven by the source follower.
In the above-described constitution, there still remain such problems yet to be solved as 1) the parasitic capacitance and 2) mixing of noises into output signals, which will be depicted hereinbelow;
1) Parasitic capacitance:
The sensitivity should be improved in order to prevent the decrease of the saturated charges when the pixels are turned considerably fine, and therefore C T in the expression (1) should be eliminated. Moreover, it is also important to eliminate the parasitic capacitance so as to improve the frequency characteristic. Therefore, the parasitic capacitance, particularly, the overlap capacitance at the drain side should be eliminated to improve the sensitivity and the frequency characteristic. Besides, the PN junction capacitance and the wiring capacitance are required to be reduced to improve the sensitivity.
2) Mixing of noises into output signals:
FIG. 14 is a sectional view showing the vicinity of the source follower and FIG. 15 is an equivalent circuit diagram of CCD. Only the first stage of the circuit is indicated in FIG. 15 for brevity's sake.
The PN junction capacitance is proportional to a contact hole 119 which is approximately 1.21*1.2 μm 2 at minimum at present, from the viewpoint of the stability of the process. Although the CCD part and FDA are separated by a field oxide film, actually they are not insulated because they use the P well in common. As is understood from FIG. 14, in a general CCD, FDA and VCCD, HCCD share the P well. That is, driving signals from VCCD, HCCD are mixed into an output signal Vo of FDA. Referring to FIG. 15, when signals are added to φVi-φV4, φH1, φH2, the signals are impressed to the P well 81 through C31-C36. The influences when the potential of the P well 81 is scattered by the P well resistance and C20-C30 appear through C37-C40 of FDA. The changing component acts as noises, with inviting the S/N deterioration in the succeeding stage or inferior operation of CDS.
The output signals are mixed also on a signal wiring. FIG. 16 is a sectional view of a signal wiring part and an equivalent circuit diagram thereof. Generally, a signal line is formed of aluminum and wired on a field oxide film 212, as illustrated in FIGS. 16(a) and 16(b). The AL layer is generally 1 μm thick, and the distance from the AL wiring to a P + layer below the field oxide film 212 is also about 1 μm. The distance between signal lines is approximately 10-20 μm depending on the design of the mask, and each signal line is approximately 10 μm wide. Assuming that S is the area of the overlap portion, .di-elect cons. is the dielectric constant of the oxide film, and d is the thickness of the oxide film, a capacitance C is represented by an expression (5) as follows;
C=.di-elect cons.·S/d (5)
Therefore, C51-C53 are almost negligible in comparison with C41-C44 in the equivalent circuit of FIG. 16(b). The driving signals of φH1, φH2, RG, φV1-φV4 (not shown) are transmitted to the P + layer (including the P well) through C41, C42, C44. Thereafter, as the P well resistance and C51-C54 take part, the P well potential is scattered and the signals are mixed into the output signal Vo through C43. This phenomenon is impossible to be prevented in the conventional example using the field oxide film.
SUMMARY OF THE INVENTION
The object of the present invention is therefore to provide an electric charge detecting apparatus for detecting electric charges with high sensitivity in a broad band while suppressing mixing of noises, with eliminating the disadvantages inherent in the prior art. The present charge detecting apparatus with little mixing of noises is realized in the constitution below:
1. A buffer electrode is provided at both ends or one end of a gate electrode;
2. A gate electrode is formed only in the active region of the transistor;
3. The actual area of the PN junction is reduced by forming a contact hole to connect polysilicon on a voltage converter means with a source follower;
4. A plurality of P wells are provided under a wiring connecting the voltage converter means and the source follower, to be connected with a source of the drive transistor in the source follower, whereby the parasitic capacitance is reduced; and
5. P + region under a field oxide film on which an output signal line from the source follower is wired is separated from other P + region or no P + region is provided, whereby mixing of noises is effectively suppressed.
According to the present invention, the parasitic capacitance can be effectively eliminated in a simple constitution. Therefore, a highly sensitive, broad-band charge detecting apparatus is achieved. The decrease of saturating charges when the pixels are rendered fine is compensated, whereby a CCD of high resolution such as an HDTV or the like is easily realized. Moreover, mixing of the other signals is reduced by separating the P wells, thus enabling reliable CDS operation with high S/N ratio. The charge detecting apparatus of the present invention is superior in sensitivity and low noise characteristic in a broad band, and therefore considerably effective in practical use.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become clear from the following description taken in conjunction with the preferred embodiments thereof with reference to the accompanying drawings throughout which like parts are designated by like reference numerals, and in which:
FIG. 1(a) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 1 of the present invention;
FIG. 1(b) is a sectional view along the line C--C' in FIG. 1(a);
FIG. 1(c) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 2 of the present invention;
FIG. 1(d) is a sectional view along the line D--D' in FIG. 1(c);
FIG. 2(a) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 3 of the present invention;
FIG. 2(b) is a sectional view along the line E--E' in FIG. 2(a);
FIG. 2(c) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 4 of the present invention;
FIG. 2(d) is a sectional view along the line F--F' in FIG. 2(c);
FIG. 3(a) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 5 of the present invention;
FIG. 3(b) is a sectional view along the line G--G' in FIG. 3(a);
FIG. 3(c) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 6 of the present invention;
FIG. 3(d) is a sectional view along the line H--H' in FIG. 3(d);
FIG. 4(a) is an enlarged plan view of a Tr used in an electric charge detecting apparatus according to Embodiment 7 of the present invention;
FIG. 4(b) is a sectional view along the line J--J' in FIG. 4(a);
FIG. 4(c) is another example similar to FIG. 4(b);
FIGS. 5(a), 5(b), 5(c) and 5(d) are a series of steps showing LOCOS process according to Embodiment 8 of the present invention;
FIGS. 6(a), 6(b), 6(c) and 6(d) are a series of steps for forming signal wirings according to Embodiment 9 of the present invention;
FIGS. 7(a), 7(b), 7(c) and 7(d) are a series of steps for forming signal wirings according to Embodiment 10 of the present invention;
FIG. 8(a) is an enlarged plan view of a floating diffusion part in an electric charge detecting apparatus according to Embodiment 11 of the present invention;
FIG. 8(b) is a sectional view along the line K--K' in FIG. 8(a);
FIG. 9(a) is an enlarged plan view of a floating diffusion part in an electric charge detecting apparatus according to Embodiment 12 of the present invention;
FIG. 9(b) is a sectional view along the line L--L' in FIG. 9(a);
FIG. 10(a) is an enlarged plan view of a floating diffusion part in an electric charge detecting apparatus according to Embodiment 13 of the present invention;
FIG. 10(b) is a sectional view along the line M--M' in FIG. 10(a);
FIG. 11(a) is a block diagram of a conventional charge transfer device;
FIG. 11(b) is an enlarged sectional view along the line A--A' in FIG. 11(a);
FIG. 12(a) is an enlarged plan view of a Tr used in the conventional electric charge detecting apparatus;
FIG. 12(b) is a sectional view along the line A--A' in FIG. 12(a);
FIG. 12(c) is a sectional view along the line B--B' in FIG. 12(a);
FIG. 13 is an explanatory view for showing parasitic capacitances related to P well part and source follower part in the conventional charge detecting apparatus;
FIG. 14(a) is antenlarged plan view of the source follower part in the conventional charge detecting apparatus;
FIG. 14(b) is a sectional view along the line C--C' in FIG. 14(a);
FIG. 15 is an equivalent circuit of a conventional charge coupled device;
FIG. 16(a) is an enlarged sectional view of a signal wiring part of the conventional CCD; and
FIG. 16(b) is an equivalent circuit of the signal wiring part in the conventional CCD.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1(a) and 1(b) show enlarged views of a Tr part in an electric charge detecting apparatus according to Embodiment 1 of the present invention. FIG. 1(a) is a plan view and FIG. 1(b) is a sectional view taken along the line C--C' of FIG. 1(a). After a gate PS1 is formed of a first polysilicon layer (PS) on a gate oxide film 100, a polysilicon oxide film 101 is obtained on the surface of the gate PS1 through thermal oxidation. Then, a gate PP2 is formed of a second polysilicon layer (PP). At this time, since the polysilicon oxide film 101 works as an insulating layer between the gates PS1 and PP2, the gates are electrically separated from each other. In Embodiment 1, the gate oxide film 100 is set to be 500-700Å thick, and the polysilicon oxide film 101 is made approximately 800-1100Å thick. The films are used in a region where the relationship, i.e., gate oxide film thickness<polysilicon oxide film thickness is held. A drain 5 and a source 6 are formed by diffusing Phosphorus and Arsenic. A contact hole 3 is formed to connect the drain 5 with the gate PP2. A contact hole 4 connects the source 6 with an AL wiring. Since it is a thermal process when the drain and the source are formed by diffusion, P and As are spread by approximately 0.7-1.0 μm. The gate PP2 is designed to project outside the gate PS1 as the above spread is taken into consideration. The overlap capacitance of the gate PS1 and the drain 5 is accordingly considerably small. Although the drain and the source may be formed by injection of ions, the succeeding thermal process (to form contact holes or the like) invites the spread as well. In a conventional method, parasitic capacitances C5, C7 are present between the gate 96 and the diffusion region (source, drain) as shown in FIG. 12(c). On the other hand, in Embodiment 1 shown in FIG. 1(b), a capacitance corresponding to the conventional C7 is not present at the drain side and the gate PP2 is connected with the drain 5, and therefore another capacitance C10 is added between the gates PS1 and PP2. The gate PP2 is connected with the drain 5 without any capacitance therebetween. The overlapping amount of polysilicon between PS1 and PP2 is 0.2-0.3 μm, and the polysilicon oxide film 101 is about 800-1100Å thick. Since the overlapping amount of PS1 and the diffusion region is 0.7-1.0 μm and the oxide film under the gates is 500-700Å thick in Embodiment 1, C7>C10 is held according to the expression (5). In other words, the problem pending heretofore, namely, the parasitic capacitance at the drain side is eliminated in Embodiment 1. The input gate capacitance of Tr from the FD part is greatly reduced, thereby improving not only the sensitivity, but the frequency characteristic. Although the formation of the drain and source and the formation of contact holes are separately described hereinabove, the drain and source, and the contact holes may be formed in one process. Since the contact hole 3 is formed to overlap with PP2, P and As, entering from the end of PP2, are spread to the end of PS1 by thermal diffusion. Therefore, the width of PP2 should be set considering this fact. If the contact hole 4 is disposed to be separated from the gate PS1, the overlapping amount with PS1 is decreased because P and As are spread by heat. That is, when Embodiment 1 is applied, one diffusion becomes enough although A, Ps are diffused twice in the conventional method in order to form the drain and source and the contact holes (to connect with the AL wiring). The process is accordingly simplified.
FIGS. 1(c) and 1(d) are enlarged views of the Tr part in an electric charge detecting apparatus according to Embodiment 2 of the present invention. FIG. 1(c) is a plan view and FIG. 1(d) is a sectional view taken along the line D--D' of FIG. 1(c). The same parts as in Embodiment 1 are designated by the same reference numerals. A gate PS8 is formed of a first polysilicon layer (PS) on a gate oxide film 100 and then a polysilicon oxide film 101 is formed through oxidation of polysilicon. Subsequently, a gate PP7 is formed of a second polysilicon layer (PP). A source 12 and a drain 11 are formed in the same manner as in Embodiment 1 through diffusion of P and As. A contact hole 9 connects the gate PS8 with the drain 11, while a contact hole 10 connects the source 12 with the gate PP7 via an AL wiring. Although the drain 11 and source 12 are spread due to the thermal diffusion, the gate PS8 is allowed to project outside the gate PP7 with the spread taken into consideration, so that the overlap capacitance between the gates PS8 and PP7 is remarkably reduced. A fresh capacitance C11 is generated between the gates PP7 and PS8 in Embodiment 2. Nevertheless, the parasitic capacitance is eliminated as a whole because C7>C11 is satisfied, similar to Embodiment 1. Accordingly, the input gate capacitance of Tr from the FD part is greatly reduced and, both the sensitivity and the frequency characteristic are improved in the simplified process,
FIGS. 2(a) and 2(b) are enlarged views of a Tr part in an electric charge detecting apparatus according to Embodiment 3 of the present invention, FIG. 2(a) being a plan view and FIG. 2(b) being a sectional view along the line E--E' of FIG. 2(a). A gate PS20 of a first polysilicon layer is formed on a gate oxide film 100. After oxidation of polysilicon, gates PP21, PP22 are formed of a second polysilicon layer. A polysilicon oxide film 101 is formed by oxidation of the first polysilicon layer. The gate PP21 is connected with a drain 23 through a contact hole 25, and the gate PP22 is connected with a source 24 through a contact hole 26 via an AL wiring. In this Embodiment 3, there is provided the second polysilicon gate PP22 at the source side, thereby making it possible to eliminate the overlap capacitance at the source side as well as at the drain side. The drain and source regions are spread by the thermal diffusion. The gates PP21 and PP22 project outside the gate PS20 by the amount of the spread, thus reducing the overlap capacitance. Although capacitances C12, C13 are generated, C7>C12 and C5>C13 and therefore, the parasitic capacitance is eliminated as a whole. Since the drain and source regions are formed in a manner of self alignment in Embodiment 3, the contact holes 25 and 26 are obtained at one time. Accordingly, the efficiency is stabilized and the process is simplified.
FIGS. 2(c) and 2(d) are enlarged views of a Tr part in an electric charge detecting apparatus in Embodiment 4 of the present invention. FIG. 2(c) is a plan view and FIG. 2(d) is a sectional view along the line F--F' in FIG. 2(c). Gates PS28 and PS29 are formed of a first polysilicon layer on a gate oxide film 100 and subjected to oxidation. Thereafter, a gate PP27 is formed of a second polysilicon layer. Due to the oxidation of the first polysilicon layer, a polysilicon oxide film 101 is formed. The gate PS28 and a drain 30 are connected by a contact hole 32, and the gate PS29 is connected with a source 31 by a contact hole 33 via an AL wiring. In Embodiment 4, the gate PS29 of the second polysilicon layer is formed also at the source side, so that the overlap capacitance can be eliminated at the source side as well as at the drain side. Since the length L of each gate PS28 and PS29 is set corresponding to the amount of the spread of the drain and source, the overlap capacitance is quite small. Although capacitances C14 and C15 are generated in Embodiment 4, similar to Embodiments 1-3, since C7>C14 and C5>C15, the parasitic capacitance is reduced as a whole. Moreover, the source and drain are formed in the same process as when the contact holes are formed, thereby simplifying the process.
In Embodiments 1-4, the gates PS1, PP7, PS20, PP27 are connected to FD83 of the conventional example. Each of the gates PP2, PS8, PP21, PP22, PS28, PS29 works as a buffer electrode.
FIGS. 3(a) and 3(b) are enlarged views of a Tr part in an electric charge detecting apparatus according to Embodiment 5 of the present invention. A plan view is shown in FIG. 3(a), and a sectional view along the line G--G' is indicated in FIG. 3(b). After gates PS35 and PS36 are formed of a first polysilicon layer on a gate oxide film 100, a polysilicon oxide film 101 is formed, and a gate PP37 is constituted of a second polysilicon layer. Contact holes 38 connect the gates PS35 and PS36 to a source 14. In the conventional constitution, the parasitic capacitance Cb is present between the gate and the P + region at the end of the field oxide film as shown in FIG. 12(b). In this case, the main component of the capacitance Cb is the capacitance between the polysilicon gate and the P + region below the gate oxide film 100 which is 500-700Å thick. The polysilicon oxide film 101 is approximately 800-1100Å. In Embodiment 5, since the polysilicon gates PS35 and PS36 are provided separately below the gate PP37 of the transistor, the capacitance Cb between the gate PP37 and P + region disappears, and the other parasitic capacitances C16 and C17 are generated between the gates PS35 and PP37, and between the gates PS36 and PP37, respectively. Cb>C16 and Cb>C17 based on the relative thickness of the oxide films. Since the gates PS35 and PS36 are connected to the source 14, the capacitances C16 and C17 assume the capacitance Cs between the gate and the source. As described by expression (3), supra, the source capacitance Cs between the gate and source is multiplied (1-G1) times, thus the source capacitance's influence on the input capacitance is controlled by G1 (G1 is the gain of a source follower in the first stage). Therefore, in Embodiment 5, not only the capacitances C16 and C17 are decreased more than the capacitance Cb, but the source capacitance's influence on the input capacitance can be reduced through manipulation of the gain of the source follower. Although the capacitance Cb disappears between the gate PP37 and P + layer, capacitances present between PS35 and the P + layer and between PS36 and the P + layer. As such, the capacitance Cb is incorporated in the capacitance C L to be driven by the source follower which is represented in the expression (4). However, the frequency characteristic is hardly influenced because of the relationship C L >>Cb.
FIGS. 3(c) and 3(d) are enlarged views of a Tr part in an electric charge detecting apparatus according to Embodiment 6 of the present invention. FIG. 3(c) is a plan view and FIG. 3(d) is an H--H' sectional view. A gate PS38 is formed of a first polysilicon layer on a gate oxide film 100 and a polysilicon oxide film 101 is formed through oxidation of the first polysilicon layer. Subsequently, a gate PP39 is formed of a second polysilicon layer. A contact hole 40 connects the gate PS38 with a source 16 via an AL wiring. The difference from Embodiment 5 is that the gates PS35 and PS36 of Embodiment 5 are formed of an integral polysilicon layer, as is the gate PS38, however, the gates PS35 and PS36 are separated from each other. In Embodiment 6 similar to Embodiments 1-4, the gate PS38 projects outside the gate PP39 of the transistor by the amount of the spread of the diffusion region. Therefore, although a capacitance C18 is added as a capacitance between the gates PP39 and PS38, the overlap capacitance at the source side (n + layer) of the gate PP39 is almost removed, and the parasitic capacitance of the gate PP39 is reduced as a whole. The reason for this is, as described in Embodiments 1-5, the difference of the thickness of the gate oxide film 100 and the polysilicon oxide film 101. Since the gate PS38 is connected at the source side, the capacitance between the gates PP39 and PS38 is regarded as the capacitance Cs between the gate and source. The capacitance Cs influences the input capacitance by a factor of (1-G1) based on the gain G1 of the source follower (expression (3), supra). According to Embodiment 6, since the overlapping amount between the gate and source is reduced much more than in Embodiment 5, the capacitance Cs is further lowered. In Embodiments 5 and 6, the gates PP37 and PP39 are connected to FD83 of the conventional example. Moreover, the gates PS35, PS36, PS38 serve as buffer electrodes.
FIG. 4(a) is an enlarged view of a Tr part in Embodiment 7 of the present invention. As shown in FIG. 12(b), the capacitance Cb exists between the polysilicon gate and P + region. In embodiment 7, the part of the polysilicon gate overlapping with the P + layer is removed. A gate PS45 is formed only in the active region to function as a transistor. A contact hole 46 is opened on the gate PS45 to be connected with an AL wiring. The gate length is not larger than 4 μm, which is enough to form the contact hole. In general, the AL wiring is used while tungsten silicide is arranged for a lower layer and aluminum is an upper layer. Therefore, even when the AL wiring is directly connected with the polysilicon gate PS45, it makes little influences to Vth (threshold value). In other words, polysilicon is not in direct contact with aluminum, but tungsten silicide is in touch with aluminum, so that the difference of the work functions is small. FIG. 4(c) illustrates a process to form a contact hole 18 at a part of the gate PS45 after oxidation of polysilicon of the gate PS45, and to form a gate PP17 of a second polysilicon layer on the contact hole 18. When a polysilicon gate is to be formed, generally, n-type impurities are doped to decrease the resistance. In the case of Embodiment 7, when n-type impurities are doped to the gate PP17, the gates PS45 and PP17 are electrically connected through the contact hole 18. Moreover, even when the gates PS45 and PP17 are connected with each other, no influences to Vth are observed in the absence of the difference of the work functions. The gate PP17 is connected with the AL wiring in the same fashion as in FIG. 4(b). In consequence, it becomes possible in Embodiment 7 to reduce the parasitic capacitance Cb between the gate and P + region.
A LOCOS process according to Embodiment 8 of the present invention will be explained with reference to FIGS. 5(a) to 5(b). In FIG. 5(a), a P well 222 is formed on an n-type substrate 223, on which an SiO2 film 221 and an Si3N4 film 220 are sequentially layered. After a photoresist 47 is applied, exposure, development and etching are carried out to remove the resist of a part to be used as an active region (where CCD operates). Etching is intended to remove the Si3N4 film 220. The Si02 film 221 is partly removed so as to surely remove the Si3N4 film. The resultant state is shown in FIG. 5(b). After the photoresist 47 is removed, a photoresist 48 is applied, exposed and developed and boron B is injected, as indicated in FIG. 5(c). The resist 48 is left in a manner to enclose the remaining part of the Si3N4 film 220 of FIG. 5(b). In accordance with the following growth of the oxide film, a field oxide film 224 is formed where the Si3N4 film 220 is not present. The Si3N4 film 220 is removed and a gate PS49 is formed of a first polysilicon layer. FIG. 5(d) results. A birds beak 252 is a part protruding triangularly from the field oxide film 224. According to Embodiment 8, since the P + layer does not ride and spread over the end of the field oxide film 224 (birds beak 252), the source and the drain can be formed up to the end of the field oxide film 224. Therefore, the capacitance conventionally brought about between the P + layer protruding from the end of the field oxide film and the gate is eliminated. That is, the capacitance between the gate PS49 and P + layer (Cb in FIG. 12) can be considerably reduced. The gate PS49 works as a first stage transistor of the source follower, and therefore the input capacitance in the first stage can be decreased.
FIGS. 6(a) to 6(d) are sectional views of a signal wiring part in Embodiment 9 of the present invention, indicating a process to form the signal wiring part subsequent to the LOCOS process. As the pending problem to be solved has been described with reference to FIG. 15, C31-C40 in FIG. 15 should be decreased to avoid mixing of noises into output signals. In the same manner as in Embodiment 8, Si3N4 is etched (FIG. 6(a)) and a photoresist 61 is removed, then a photoresist 63 is applied, followed by the injection of boron B (FIG. 6(b)) for forming a P + region. At this time, since the signal wiring part is covered with the photoresist 63, boron B is not injected into the signal wiring part (FIG. 6(b)). Then, a field oxide film 230 is formed through oxidation (FIG. 6(c)), and an interlayer film 231 (of BSPG, NSG or the like) is laminated and an AL wiring is provided (FIG. 6(d)). In Embodiment 9, the part below the field oxide film 230 is changed from P + layer to P layer (P well 62). Therefore, the capacitance between the AL wiring and P layer (P well 62) is reduced approximately 30%, so that the CCD driving signals (RG, φH1, φH2, φVi-φV4) are less mixed into the output signal Vo.
FIGS. 7(a) to 7(d) are sectional views of a signal wiring part according to Embodiment 10 of the present invention, specifically, showing a process to form the signal wiring part after the LOCOS process. FIG. 7(a) indicates the same state as in Embodiment 9, but without the P well.
After a photoresist 64 is removed and a photoresist 65 is applied, exposed and developed, boron B is injected to an AL signal wiring part alone (FIG. 7(b)). When a field oxide film 232 is formed, the P + regions do not come in touch with each other although the regions actually spread (FIG. 7(c)). An interlayer film 233 is laminated and thereafter, an AL wiring is provided. Accordingly, since the P + regions are separated from each other under the signal wiring, CCD driving signals (RG, φH1, φH2, φVi-φV4) are mixed less with the output signal Vo.
FIGS. 8(a) and 8(b) are structural diagrams of the vicinity of an FD part in accordance with Embodiment 11 of the present invention. FIG. 8(a) is a plan view and FIG. 8(b) is a sectional view taken along the line K--K' of FIG. 8(a). The FD part has conventionally been obtained when the contact holes are formed (cf FIG. 14), and the PN junction capacitance C PN of the FD part is proportional to the size of the contact hole. It is a characteristic of Embodiment 11 that the polysilicon layer is overlapped with the contact hole, thereby to make the effective hole (contact area with the silicon substrate) small. As is clear from FIG. 8(a), in Embodiment 11, a gate PS71 of the first stage drive transistor is extended to FD72 and, a contact hole 70 is formed astride the gate PS71. FD72 is obtained as P and As are thermally diffused. Then, the gate PS71 is connected with the silicon substrate (FD72) by an AL wiring. Since a part of the contact hole 70 covered with the gate PS71 is not provided with an n + layer (except for the part spread by thermal diffusion), the n + layer formed on the silicon substrate becomes smaller than the conventional one. FIG. 8(b) indicates the final state when the n + layer is spread through thermal diffusion. In consequence to this, FD72 (n + layer) becomes equivalent to that the minimum size in the conventional process is greatly reduced, thus eliminating the PN junction capacitance on a large scale.
FIGS. 9(a) and 9(b) are structural diagrams of the vicinity of an FD part in Embodiment 12 of the present invention. FIG. 9(a) is a plan view and FIG. 9(b) is a sectional view along the line L--L' of FIG. 9(a). Embodiment 12 is characterized in that a contact hole 75 is formed in a manner to stretch over the polysilicon layer and the silicon substrate. As is understood from FIG. 9(a), a polygon is formed of polysilicon on the FD part. The thus-formed polygonal polysilicon 73 may be any one of the polysilicon layer. As is clear from the cross section of FIG. 9(b), a contact hole 75 is formed covering both the polysilicon layer 73 and the silicon substrate. Therefore, P and As diffused when the contact hole is formed never enter a part covered with the polysilicon layer 73. FD74 is formed through diffusion of P and As and is spread by thermal diffusion, therefore increasing the area more or less than in the initial state. As a result, FD74 is rendered equivalent to that when the minimum size of the contact hole is considerably reduced, and the PN junction capacitance C PN is removed so much. The feature of Embodiment 12 is that the contact hole is formed on one polysilicon. For example, in the case where a plurality of polysilicons 73 are arranged and contact holes are formed in the gap of the polysilicons, the size of FD74 is determined according to the etching rule of the polysilicon. In Embodiment 12, however, the size of FD74 can be controlled by the overlapping amount of the contact hole 75 with the polysilicon 73, and moreover, the PN junction capacitance C PN is greatly eliminated.
FIGS. 10(a) and 10(b) are structural diagrams of the vicinity of an FD part in Embodiment 13 of the present invention. FIG. 10(a) is a plan view and FIG. 10(b) is a sectional view along the line M--M' of FIG. 10(a). In the aspect of Embodiment 13, a P well 75 of the drive transistor is extended from the FD part to below the AL wiring of the initial stage transistor. The forming method of the P well in Embodiment 9 is utilized for the above purpose. The P well 75 is connected with a source 78 of the drive transistor (FIG. 10(a)). The P well 75 is arranged below a gate PS76 of the drive transistor (below the field oxide film) from a contact hole 77. Therefore, the wiring capacitance C4 in the expression (2), supra, is the capacitance between the AL wiring part and the P well 75. Since the P well 75 is connected with the source 78 of the drive transistor in Embodiment 13, the above wiring capacitance C4 can be regarded as the capacitance between the gate and source of the drive transistor. The capacitance Cs between the gate and source is multiplied (1-G1) times as described in Embodiments 5-7, and its influence on the input capacitance can be reduced by manipulating G1 according to expression (3), supra. In other words, since the input capacitance is eliminated, the total parasitic capacitance C T is reduced. If the diffusion region (n + ) at the source side is extended to below the AL wiring, it brings about the same result.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom. | An electric charge detecting apparatus comprising vertical CCD, horizontal CCD and floating diffusion amplifier comprised of floating diffusion layer and source follower amplifier comprising a MOS transistor wherein a buffer electrode is arranged at one end of a gate electrode of the MOS transistor, the gate electrode is formed within an active region of the MOS transistor, a contact hole is provided for connecting a polysilicon layer arranged on a charge-voltage transformer and the source follow or plural P wells are formed and one of them is arranged under a wiring connecting the charge-voltage transformer and the source follower and connected to a source of a drive transistor. Said electric charge detecting apparatus further comprising, P + region arranged under a field oxide film on which an output signal wiring from the source follower is electrically isolated from another P + region or no P + regions are provided under the field oxide film. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an information input and output apparatus, more particularly, to an information input and output apparatus comprising an active matrix drive type display device and a light pen.
2. Description of the Related Art
As an information input and output apparatus, conventionally, there has been used an apparatus integrally comprising a separate CRT display device and a separate input apparatus for inputting information using a light pen. The apparatus of this type has a disadvantage that it is not suitable for portable use since the power consumption is relatively large and the size of the apparatus is relatively large.
In order to solve the above problems, there has been proposed in the Japanese patent laid open publication (JP-A) No. 61-6729 published on Jan. 13, 1986, an information input and output apparatus of a completely integral type comprising a combination of a liquid crystal display device and a light emitting type light pen. In the proposed information input and output apparatus, plural photoelectric transducers are arranged inside of an active matrix drive type liquid crystal display device so as to oppose respective pixel electrodes.
FIG. 1 shows a structure of a pixel of the conventional liquid crystal display device of this type.
Thin film transistors (referred to as TFTs hereinafter) for driving the pixel electrodes and photodiodes for detecting light projected from a light pen which are photoelectric transducers each having two terminals are formed on an electrically insulating substrate (not shown) in a matrix shape so as to oppose the pixel electrodes (not shown), respectively.
A TFT comprises a source line 63, a gate line 65, and a drain electrode 67, as shown in FIG. 1. In one pixel of the liquid crystal display device, in addition to these components, a photoconductive semiconductor film 62 for detecting light projected from the light pen is formed on the gate line 61 so as to correspond to each pixel electrode, and a data read line 69 is formed on the photoconductive semiconductor film 62 so as to solidly cross the gate line 61 in parallel to the source line 63.
FIG. 2 shows a conventional circuit for detecting a position of the light pen.
Referring to FIG. 2, after an image signal is inputted to a line memory 43 with a clock signal having a predetermined frequency and is stored therein, the image signal is read out from the line memory 43 and is outputted to each source line 63. Responsive to the clock signal, a scan pulse generator 81 generates a scan pulse and outputs it to the gate lines 61, which is connected to the data read line 69 through the photoconductive semiconductor film 62. The drain electrode of each TFT is connected to a capacitor Cs for storing a signal and each pixel electrode (not shown) which is connected to each opposing electrode (not shown) through the liquid crystal layer 110. Each data read line 69 is connected to one input terminal of each comparator 44, which compares the voltage of the data read line 69 with a reference voltage Vref so as to detect the position of the light pen when a pixel is indicated by the light pen so that a beam of light projected therefrom is incident onto one of photoconductive semiconductor films 62.
The information input and output apparatus of this type shown in FIGS. 1 and 2 has a relatively small power consumption, and can be miniaturized. However, it is necessary to form each data read line 69 in parallel to the source line 63, resulting in twice the number of the electrodes in the column direction of the matrix when each data read line 69 is not formed. In this case, the method of fabricating the liquid crystal display device of this type becomes extremely complicated, and the information input and output apparatus has such a disadvantage that it is extremely difficult to fabricate it. Further, since the structure of the apparatus of this type becomes complicated, there are such problems that an area of each opening on each pixel decreases and the contrast of the displayed image is lowered.
SUMMARY OF THE INVENTION
An important object of the present invention is to provide an information input and output apparatus which can be miniaturized and can be suitable for portable use, and further has a power consumption smaller than the conventional apparatuses.
Another object of the present invention is to provide an information input and output apparatus which does not need any electrode for detecting the position of the light pen.
A further object of the present invention is to provide an information input and output apparatus being capable of displaying an image without lowering the contrast thereof.
In order to accomplish the above objects, according to one aspect of the present invention, there is provided an information input and output apparatus comprising:
display means for display an image according to an image signal, said display means having plural pixel electrodes formed in a matrix shape on a transparent substrate;
plural row electrode lines being formed on said transparent substrate so as to be parallel to each other;
plural column electrode lines being formed on said transparent substrate so as to cross said row electrode lines at substantially right angle in parallel to each other;
switching means for driving said display means responsive to a predetermined voltage to be applied to one of row electrode lines and a predetermined voltage to be applied as said image signal to one of column electrode lines;
a light pen for projecting light onto said display means;
a photoconductive layer being formed between each of said row electrode lines and each of said column electrode lines at each intersection of said row electrode lines and said column electrode lines so as to receive light projected from said light pen; and
detecting means for detecting a position of said light pen located on said display means responsive to a signal induced to each of said column electrode lines.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become clear from the following description taken in conjunction with the preferred embodiment thereof with reference to the accompanying drawings, in which:
FIG. 1 is a top plan view showing a structure of a pixel of a conventional active matrix drive type liquid crystal display device;
FIG. 2 is a schematic circuit diagram showing a conventional circuit for detecting a position of a light pen and a conventional circuit for driving TFTs which are applied to the display device shown in FIG. 1;
FIG. 3 is a perspective view showing a structure of a pixel of an active matrix drive type liquid crystal display device of a preferred embodiment according to the present invention;
FIG. 4a is a schematic cross sectional view taken on line A-A' of a photodetecting section shown in FIG. 3;
FIG. 4b is a schematic cross sectional view of the liquid crystal device, taken on line B-B' of FIG. 3;
FIG. 5a is a top plan view showing a light shutter filter formed on the display device shown in FIG. 3;
FIG. 5b is a top plan view showing a light shutter filter of a modification of the light shutter filter shown in FIG. 5a;
FIG. 6 is a schematic circuit diagram showing a circuit for detection a position of a light pen and a circuit for driving TFTs which are applied to the display device shown in FIG. 3; and
FIG. 7(a)-(e) is a timing chart showing an action of the circuit for detecting the position of the light pen shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An active matrix drive type liquid crystal display device of a preferred embodiment of an information input and output apparatus according to the present invention will be described below with reference to the attached drawings.
FIG. 3 shows a structure of one pixel of the active matrix drive type liquid crystal display device, FIG. 4a shows a photodetecting section 42 of the liquid crystal display device, and FIG. 4b shows a display section 40 thereof.
Referring to FIG. 3, there are formed in a matrix shape on an electrically insulating glass substrate 9, TFTs 41 for driving the photodetecting section 42 formed at each intersection 4 of electrically conductive gate lines 1 and electrically conductive source lines 3 and for driving the display section 40, each TFT having a gate electrode 5, a source electrode 6 and a drain electrode 7.
A method of fabricating the TFT 41 and the photodetecting section 42 will be described below with reference to FIGS. 3 and 4a. It is to be noted that the method for fabricating the TFT 41 and the photodetecting section 42 of only one pixel will be described hereinafter for convenience of the description.
First of all, the gate line 1 and the gate electrode 5 for one TFT 41 electrically connected to the gate line 1 which are made of an electrically conductive material such as Ta, ITO+Ta are formed on the transparent glass substrate 9. Then, after an area of the intersection 4 of the gate line 1 and the source line 3 is covered by a resist film (not shown) in order that a gate electrically insulating film (not shown) and an i type a-Si layer are not formed on the area of the intersection 4, the gate insulating film is formed thereon, and further, the i type a-Si layer of the TFT 41 is piled up thereon. Thereafter, an n type a-Si layer (not shown) for forming the TFT 41 and a photoconductive semiconductor layer 2 is formed thereon. In order to form the TFT 41 and the photoconductive layer 2, the a-Si layer is etched so that there remain thereon a partial portion of the a-Si layer which becomes a portion of the TFT 41 and another partial portion thereof which becomes the photoconductive layer 2.
Thereafter, a pixel electrode 8 of ITO is formed on the insulating substrate 9, and then, the source line 3 and the source electrode 6 electrically connected to the source line 3 are formed on the insulating substrate 9 so that the source line 3 crosses the gate line 1 at right angles and the source electrode 6 is formed on the a-Si layer of TFT. Then, it is necessary to form the source line 3 on the insulating substrate and the photoconductive layer 2 so that the width of the source line 3 is smaller than that of the photoconductive layer 2, as shown in FIG. 4a, in order that the photoconductive layer 2 of the a-Si layer can receive a beam of light projected from a light pen 300, resulting in that photodetecting portions 2a of the photoconductive layer 2 are formed which are exposed to a beam of light projected therefrom.
Furthermore, the drain electrode 7 of Ta or ITO+Ta is formed on a partial area of the a-Si layer of the TFT 41 and a partial area of the pixel electrode 8. It is to be noted that the gate line 1, the gate electrode 5, the source line 3, the source electrode 6 and the drain electrode 7 may be made of a metal such as Ni, Cr, Mo in place of Ta or ITO+Ta.
On the other hand, in the display section 40 shown in FIG. 4b, there is provided a liquid crystal layer 110 between the pixel electrode 8 and an opposing electrode 111 which is grounded or to which an opposing electrode driving signal is applied. Further, a transparent electrically insulating glass substrate 112 is formed on the opposing electrode 111.
Further, there is formed a light shutter filter 10 on the portions of the glass substrate 112 which oppose to the gate line 1, the gate electrode 5 and the source line, as shown in FIG. 5a. The light shutter filter 10 passes therethrough substantially only light having a predetermined wavelength substantially equal to that of light projected from the light pen 300, and shuts light having a relatively low intensity like that of the surrounding light. Alternately, shown in FIG. 5b, the light shutter filter 10 may be formed on the portions of the glass substrate 112 which oppose to the photodetecting section 42, and a light shielding member 11 of black color for shutting all the light may be formed on the other portions than the portions where the light shutter filter 10 is formed.
The light shutter filter 10 shuts light having wavelengths other than transmitted wavelength. Further, the light shutter filter 10 has a property of attenuating the light so that the electrons which exist in the valence band of the photoconductive layer 2 are hardly excited by the surrounding light. Therefore, upon a normal liquid crystal display, the surrounding light hardly influence the liquid crystal display. On the other hand, the light shutter filter 10 passes a beam of light having an energy projected from the light pen 300, which is larger than that of the surrounding light.
The light pen 300 comprises a light source and a lens which are mounted in a pen-shaped case. As the light source thereof, there is used a light source having a narrow spectrum such as a light emitting diode (LED), a semiconductor laser. Light emitted from the light source is converged by the lens which is mounted at the end of the light pen 300, and a beam of light is projected onto the liquid crystal display device. As shown in FIG. 4a, a beam of light projected from the light pen 300 is incident onto the photodetecting portions 2a of the photoconductive layer 2 which has a width larger than that of the source line 3, through the light shutter filter 10 shown in FIG. 5a.
FIG. 6 shows a circuit for driving the TFTs 41 and a circuit for detecting the position of the light pen 300 which are applied to the liquid crystal display device and FIG. 7 is a timing chart showing the action of the circuit for detecting the position of the light pen 300. In FIG. 6, the same components as that shown in FIG. 2 are denoted by the same numerical references as that shown in FIG. 2.
Referring to FIG. 6, the liquid crystal layer 110 is driven by a line sequential drive method of an active matrix drive manner which is known to those skilled in the art. Responsive to a clock signal, a scan pulse generator 81 generates a scan pulse and outputs it to the gate lines 1 sequentially. On the other hand, an image signal of one horizontal scan period is latched by a line memory 202 according to a sampling signal outputted from a serial to parallel shift register 201. It is to be noted that the sampling operation of the image signal is started responsive to a source start pulse inputted to the shift register 201.
After the latch operation of the image signal of one line to be outputted for the next period has been completed, data stored in an output buffer memory 204 which outputs the data at present are cleared responsive to a discharge pulse. Thereafter, the image signal of one horizontal scan period having been latched by the line memory 202 is transferred to the output buffer memory 204 at a predetermined timing responsive to a transfer pulse.
At that time, the TFT 41 which connected to the gate line 1 to which the scan pulse is applied by the scan pulse generator 81 is turned on so as to active the liquid crystal layer 110 which is disposed on the pixel electrode 8. On the other hand, when a beam of light is projected onto the photodetecting section 42 from the light pen 300, the resistance of the photoconductive layer 2 decreases, and then, the scan pulse having been applied to the gate line 1 is leaked and transferred into the the source line 3. In the present preferred embodiment, the leaked signal is utilized as a position information signal of the light pen 300.
There is provided a time interval for reading the position information signal between the aforementioned discharge pulse and the aforementioned transfer pulse, and the position information signal of the light pen 300 is read out from the source line 3 responsive to a read start pulse which is generated by a read start pulse generator 82 responsive to the clock signal. Namely, responsive to the read start pulse, analog switches 42 are turned on, and then, the position information signal is transferred from the source line 3 to the comparators 44 through the analog switches 42. Thereafter, the position information signal is compared with a reference voltage Vref and is amplified by the comparators 44, and then, the position information signal is latched by RS type flip flops 45. The signals outputted from respective flip flops 45 are inputted to an OR gate OR1
The signals outputted from respective comparators 44 are reset to the Low level or "0"at the beginning of each line. Thereafter, when a beam of light projected from the light pen 300 is incident onto the photoconductive layer 2 of the photodetecting section 42 of the liquid crystal display device, the signal outputted from the comparator 44 which is connected through the analog switch 42 to the source line 3 changes to the High level or "1", and the signal outputted from the OR gate OR1 becomes the High level or "1". The signal outputted from the OR gate OR1 is inputted to a counter 49 through an AND gate AND2 which is controlled to be gated according to the clock signal. The scan pulses while the signal outputted from the OR gate OR1 is the Low level or "0"is counted by the counter 49, and then, data of the number of the counted scan pulses are outputted as Y coordinate data.
On the other hand, the signals latched by respective RS type flip flops 45 are transferred to another parallel to serial shift register 46, and the signals outputted from the shift register 46 are outputted to a counter 48 through an RS type flip flop 47 and one input terminal of an AND gate ANDI, to another input terminal of which the clock signal is inputted. Then, the clock signal is counted by the counter 48 until the signal outputted from the flip flop 47 becomes the High level or "1"for the first time, data of the number of the counted clock signal are outputted as X coordinate data.
The surrounding light can be prevented from influencing to the aforementioned operation for detecting the position of the light pen 300 by adjusting the sensitivity of each of the light shutter filter 10 and the photoconductive layer 2. However, if the surrounding light influences thereto, it is necessary to adjust the reference voltage Vref which is inputted to the comparators 44. Alternately, the light emitted from the light source of the light pen 300 may be flushed with a predetermined period, and only the signal synchronous with the flushed light may be read out from the source lines 3 and amplified, resulting in the position information signal.
According to the preferred embodiment, the photoconductive layer 2 is formed between the gate line 1 and the source line 3 at the intersection 4 of these lines 1 and 3. Therefore, it is not necessary to provide the data read lines 69 for reading out the position information signal of the light pen 300. Then, the structure of the liquid crystal display device having the photodetecting section 42 becomes simpler than that of the conventional display device shown in FIGS 1 and 2. Further, the area of the opening of each pixel can be prevented from decreasing, and the contrast of the displayed image can be prevented from lowered. The liquid crystal display device of the preferred embodiment can be miniaturized as compared with the conventional apparatus, and is suitable for portable use and has a power consumption smaller than the conventional apparatus.
In the present preferred embodiment, the TFTs 41 are formed on the glass substrate 9. However, the present invention is not limited to this. There can be used a liquid crystal display device of reflection type mode wherein the TFTs 41 are formed on a semiconductor substrate of SI.
In the present preferred embodiment, the photoconductive layer 2 of the photodetecting section 42 is made of a-Si, however, the present invention is not limited this. The photoconductive layer 2 may be made of a photoconductive material such as CdS, GaAs, SeTe.
In the present preferred embodiment, the RS flip flops 45 are used. However, the present invention is not limited to this. Peak holding circuits may be used in place of the flip flops 45.
It is understood that various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of the present invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be construed as encompassing all the features of patentable novelty that reside in the present invention, including all features that would be treated as equivalents thereof by those skilled in the art to which the present invention pertains. | An information input and output apparatus includes an active matrix type display device and switching device. In the information input and output apparatus, the display device displays an image according to an image signal, and has plural pixel electrodes formed in a matrix shape on a transparent substrate. The switching device drives the display device in response to a predetermined voltage to be applied to one of row electrode lines and a predetermined voltage to be applied as the image signal to one of column electrode lines. A photoconductive layer is formed between each of the row electrode lines and each of the column electrode lines at each intersection of the row electrode lines and the column electrode lines in a structure relation to receive light projected from the light pen. When light projected from a light pen is incident onto the photoconductive layer, the resistance thereof decreases. Then, a detection circuit detects a position of the light pen located on the display means responsive to a signal corresponding to the decrease of the resistance of the photoconductive layer which is induced to each of the column electrode lines. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to gelled fuels and solvents in US class 44, subclass 272. Specifically the invention relates to gel thickeners that reduce vapor pressure in fuels and solvents and are shear thinning (pseudoplastic or thixotropic) or are shear thickening and remain pourable and flowable. Still more specifically, the invention relates to nonaqueous gels made with diblock copolymers that reduce the Reid Vapor Pressure of gelled gasoline and lower the total volatility of gelled hydrocarbon solvents. These gels may contain secondary amino acid or triblock polymer gelling agents. The invention includes gel compositions and methods of making gels.
[0003] 2. Background Information
[0004] The vapor pressure of hydrocarbon fuels such as gasoline is controlled by both state and federal regulations. The purpose of these regulations is to reduce the production of environmental pollutants including ozone that cause smog. The economics of refining favors adding cheap butane fractions to the blend to produce high vapor pressure gasoline. Environmental regulations require refineries to produce reduced vapor pressure gasoline that contains less butane. This is expensive. Oxygenates, which are oxygen containing compounds such as ethanol, are sometimes blended into gasoline to lower undesirable emissions. These oxygenates are expensive and do not remove the need to control the gasoline's vapor pressure. Currently oxygenates are government subsidized and some studies report that oxygenates do not significantly reduce ozone formation. It is still necessary to reducing the amount of butane in the blend to lower the gasoline's vapor pressure.
[0005] Like gasoline, industrial and consumer hydrocarbon solvents contribute to the volatile organic compounds released into the environment that produce ozone and cause smog. These solvents are not as highly regulated as gasoline, but their control regime is getting tougher and it would certainly be desirable to lower their total volatility to reduce the amount of volatile organic compounds released into the atmosphere.
[0006] When the amount of butane in gasoline is reduced, the octane rating of the gasoline goes down, which makes engines knock and hard to start. It would be desirable to be able to lower the vapor pressure of gasoline and hydrocarbon solvents without removing as much butane from the blended gasoline.
[0007] Gel thickeners have been tested to lower the vapor pressure of gasoline, especially in aviation fuels. The prior art teaches that gelled gasoline does have lower vapor pressure. The high viscosity of the gelled fuel required that the gel be degraded by in-line degraders in the fuel lines before the fuel was pumped, filtered or injected into an engine. This requirement for the use of in-line degraders made the use of gelled fuels economically impractical.
[0008] To better understand the present invention, it is helpful to understand vapor pressure. Vapor pressure is the measure of how volatile a compound is; the lower the vapor pressure, the less volatile the compound. From the standpoint of petroleum characterization, lighter hydrocarbons (i.e. butane) have a higher vapor pressure than heavier hydrocarbons.
[0009] The volatility of a blended gasoline is characterized by its Reid Vapor Pressure (RVP.) There is a direct correlation between the ability of a gasoline to operate an engine in both cold and hot start situations and its RVP. Also, the ideal RVP for a blended gasoline depends on the season (approximately 13 psi RVP in winter, 8.5 psi RVP in summer). Furthermore, the change in atmospheric pressure with altitude and variations in temperature means that the RVP of a blended gasoline must be localized. This means that the RVP of gasoline sold in Denver is different than the gasoline sold in Death Valley.
[0010] Gasoline, from a refinery point of view, it is a mix of hydrocarbons that, when combined, meet vapor pressure specifications. These hydrocarbons fall in the C 4 to C 12 range. Only isobutane and normal butane have RVPs above the limit of 13 psi. Therefore, addition or removal of these butane blending components is used to adjust the gasoline's RVP to meet vapor pressure requirements. The procedure for estimating the volume of butane required is outlined in Petroleum Refining in Nontechnical Language (Pennwell Nontechnical Series) by William L. Leffler. It should also be noticed that these butanes are the lowest cost components in the gasoline blend. Their elimination to lower RVP increases the price of the final gasoline product.
[0011] The Clean Air Act amendments of 1990 require the use of reformulated gasoline with oxygen additives such as ethanol (sometimes just called “alcohol”) and methyl tertiary butyl ether (MTBE) in areas of the United States that have substantial ozone pollution. These gasolines are sold in cities on the East Coast, in the Midwest, Texas, and California—particularly during the summer months, when near-ground ozone is most prevalent. This ozone is formed when pollutants from many different sources, including automobiles, react chemically in the presence of sunlight. Reformulated gasolines are designed to lower the emissions of vehicle pollutants, including those that contribute to ozone formation. In addition to oxygen additives, the fuels have a number of other characteristics that lower emissions.
[0012] But the oxygen additives in reformulated gasolines have raised environmental concerns. MTBE, for example, has leaked into drinking water in California, leading the state to phase out the use of this additive. Other states will probably also phase out the use MTBE. Because questions persist over which types of reformulated gasolines are preferable in improving air quality, the Environmental Protection Agency (EPA) recently asked the National Research Council (NRC) to study methods for certifying gasoline blends with oxygen additives.
[0013] The NRC found that, compared with MTBE blends, ethanol blends result in more pollutants evaporating from vehicle gas tanks. Ethanol blends also increase the overall potential of emissions to form ozone. Recent test data indicate that the potential for either additive to lower smog levels is small and will continue to decrease as other measures to reduce vehicle emissions take effect.
[0014] The EPA has established a two-phase reduction in summertime commercial gasoline volatility. These rules reduce gasoline emissions of volatile organic compounds (VOC) that are a major contributor to ground-level ozone (smog). Phase I was applicable to calendar years 1989 through 1991. Depending on the state and month, gasoline RVP was not to exceed 10.5 psi (pounds per square inch), 9.5 psi, or 9.0 psi. Phase II is applicable to 1992 and later calendar years. Depending on the state and month, gasoline RVP may not exceed 9.0 psi or 7.8 psi.
[0015] The prior art in gasoline RVP control is the production of low RVP gasoline. To make low RVP gasoline, refiners simply lower the vapor pressure by removing high vapor pressure components, i.e. the cheap butanes. Low RVP gasoline has a lower vapor pressure and thus a lower evaporation rate and lower volatility than conventional gasoline, but it costs more to make.
[0016] Lowering the vapor pressure of gasoline also reduces the evaporative emissions generated during vehicle refueling and therefore decreases the emissions of volatile organic compounds (VOCs) and other ozone-forming emissions.
[0017] Currently, the Regional Low RVP Gasoline program requires that low RVP gasoline be used in 95 central and eastern Texas counties during the summer months when ozone pollution is at its worst. The program, which began May 1, 2000, requires that all gasoline sold from retail gasoline-dispensing facilities within the affected counties have a maximum Reid vapor pressure of 7.8 pounds per square inch (psi) from June 1 through October 1 of each year. Gasoline suppliers are required to supply low RVP gasoline to the affected counties from May 1 through October 1 of each year.
BRIEF SUMMARY OF THE INVENTION
[0018] The present invention is a gelled fuel or solvent, for example gasoline, containing an effective amount of at least one diblock copolymer. The effective amount of copolymer may be determined on a case by case basis by those skilled in the art. It will be the type and amount of diblock copolymer that results in the gelled gasoline having a desired RVP and viscosity and also being pseudoplastic shear thinning so it can pass though fuel filters, pumps and injectors. In the case of gelled hydrocarbon solvents it may be sometimes desirable to add amino acid gelling agent or triblock, radial or star copolymers to the gel to lower the total amount of polymer required to produce an acceptable gel. The addition of these gelling agents and non diblock copolymers will cause the gel to become Newtonian or shear thickening, but not so much as the prior art and the gelled solvent will still be flowable. Flowable means that it can be poured easily and will flow through pipes.
[0019] The diblock copolymer should have a molecular weight between about 100,000 and about 500,000. The molecular weight of the diblock polymer, or diblock polymers, is a function of the desired viscosity of the gelled fuel or solvent, the resulting vapor pressure of the gelled fuel and its ability to be flowable or shear thinning for use with fuel injectors, pumps and filters so as to avoid the requirement of in line degraders.
[0020] In the present invention, the embodiment of the invention comprising gasoline gelled with diblock copolymer is pseudoplastic. The gelled gasoline has a viscosity higher than the base ungelled gasoline, which lowers the vapor pressure and the gelled fuel exhibits a significant instantaneous reduction in viscosity when it flows through a small orifice, such as the fuel injector of an automotive engine. One benefit of the present invention is to allow formation of useful gels from a wide range of gasoline and solvent products, including by way or example, and not of limitation: Conosol® and Drakeol® hydrocarbon oils and solvents made by Penreco of Houston, Tex.; gasoline and other hydrocarbon containing fuels and lubricants such as diesel oil, jet fuel; and low viscosity specialty hydrocarbon products including penetrating oils and solvents sold under the trademarks Liquid Wrench® and WD-40®.
[0021] The vapor pressure reducing gelled fuels and solvents taught by the present invention may use one or more of a wide variety of diblock copolymers such as the hydrogenated and unhydrogenated diblock copolymers manufactured under the trademark Kraton®. The preferred embodiment of the present invention for use with gasoline and Conosol solvents uses Kraton® G-1702 diblock copolymer. This material is sold by Kraton Polymers of Houston, Tex.
[0022] The gelled hydrocarbon fuels and solvents taught by the present invention may also contain small amounts of amino acid gelling agents and triblock, radial or star copolymers in addition to the primary diblock copolymer. These low amounts of secondary gelling agents are useful in the range of about 0.1 to 5.0 weight percent to increase the viscosity of the gelled solvent while still allowing the gelled solvent to be pourable and flowable.
[0023] Yet a further benefit of the present invention is reduction in hydrocarbon product vapor pressure lowers the total amount of volatile organic compounds (VOC) that are released by the product into to the environment at a given temperature and pressure. One example of this benefit is that gelled fuel in an empty gas tank would have a lower vapor pressure, i.e. less VOC per unit volume of the gas tank, and thus would release less VOC pollution into the atmosphere during refueling, when the VOC vapor in the gas tank is forced out of the tank by the fuel flowing into the tank.
[0024] Yet another advantage of the pseudoplastic shear thinning gelled gasoline taught by the present invention is that the lower vapor pressure of the present invention lowers the risk of hydrocarbon-air explosion, while at the same time providing a gelled gasoline or solvent product that can flow through pumps, filters and small orifices, such as the jets in pores in fuel filters and fuel injectors in reciprocating gasoline or diesel engines, which may be stationary or may be in a car, truck or other mobile machinery. This advantage includes use of the present invention to provide a sprayable hydrocarbon containing gel with reduced vapor pressure to make fuel air explosion less likely while retaining the ability to flow properly through fuel spray nozzles in an aircraft reciprocating or turbojet engine or through the fuel injector plate orifices in an expendable or reusable rocket engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a graph showing the weight vs. time plot for a hydrocarbon solvent gelled according to the present invention and the ungelled hydrocarbon solvent. The solvent is Penreco Conosol 260.
[0026] FIG. 2 . is a bar graph showing the Reid Vapor Pressure of gasoline gelled according to the present invention compared to the Reid Vapor Pressure of ungelled gasoline.
[0027] FIG. 3 is a bar graph showing the reduction of viscosity of the gelled gasoline with increasing shear.
DETAILED DESCRIPTION OF THE INVENTION
[0028] Numerous commercially available block copolymers can be used in embodiments of the invention. For example, various grades of copolymers sold under the trade name of Kraton® from Kraton Polymers, Houston, Tex. can be used. In some embodiments, the diblock copolymers are one or more of Kraton® G-1701 and Kraton® G-1702. Both Kraton® G-1701 and Kraton® G-1702 are diblock copolymers comprising hard styrene blocks and saturated poly(ethylene/propylene) blocks. Kraton® G-1701 has a specific gravity of about 0.91, and is reported to have a tensile strength of about 300 psi as measured on films cast from toluene, with Instron jaw separation of 10 inches per minute at a temperature of 25° C. and dumbbell specifications cut with ASTM die D. The styrene to rubber content of Kraton® G-1701 is reported by the manufacturer to be about 37:63, and the Brookfield viscosity is about greater than 50,000 cps (toluene solution, cps at 77° F., 25% by weight). The Shore A hardness is about 72. Kraton® G-1702 has a styrene content of about 28% and a Shore A hardness of about 75.
[0029] In addition, copolymers sold under the trade name of Vector® available from Dexco and Septon® from Kuraray also may be used. Table I lists some commercially available block copolymers which may be used in embodiments of the invention.
[0000]
TABLE I
Block
Polystyrene
Copolymer
Type
Content (%)
Comment
Kraton ® G 1702
SEP
28
hydrogenated diblock
Kraton ® G 1701
SEP
37
hydrogenated diblock
Septon ® 1001
SEP
35
Hydrogenated diblock
Vector ® 6030
SB
30
Unsaturated diblock
Solprene ® 1430
SB
40
Unsaturated diblock
[0030] Kraton® G-1702 is used with gasoline and solvents in the examples set out below. However the remaining examples of diblock polymers, as well as other diblock copolymers having similar characteristics, may be used depending on the values of pseudoplasticity, viscosity and RVP desired in the final gelled solvent or fuel.
[0031] Penreco Conosol 260 is a high-purity, low-odor aliphatic solvent that is composed primarily of C 13 -C 20 isoparaffinic and cycloparaffinic hydrocarbons. It is a low-toxicity product that contains less than 0.5% aromatics, and it has a higher solvent strength than competitive aliphatic solvents. Conosol 260 is environmentally friendly and meets numerous FDA regulations (21 CFR) for direct and indirect food additives. Penreco has determined that this product meets the low vapor pressure (LVP) VOC exemption for consumer products as set by the California Air Resources Board.
[0032] The chemical composition of Penreco Drakesols is predominantly saturated hydrocarbons. These compounds may be branched, straight chain or saturated cyclic structures. The aromatic content is very low and olefins are almost nonexistent.
[0033] Any hydrocarbon fuel or solvent with similar properties may be used in the present invention. The weight percent of the copolymer is selected in order to yield the desired viscosity, shear thinning and RVP. In the preferred embodiment of the invention, the weight percent of copolymer is from about half a weight percent to about twently weight percent. This yields a gelled fuel or solvent that has a viscosity range from about 100 SUS to about 2000 SUS, whereby the gelled fuel can be used fuel injector. The injection pressure ranges in, for example, a Jaguare engine, is from 230 bar (3,380 psi) at low engine speeds to 1,500 bar (22,000 psi) when engine speed exceeds 2,000 rev/min.
[0034] The gelled fuels and solvents taught by the present invention may contain any well known additive used in gasoline (discussed in more detail below), chemical and physical stabilizers, long chain alcohols, fragrances, insecticides, waxes, other solvents, oils and long chain organic acids, long chain organic bases, mineral oils, oils derived from vegetables and fruits, and animal derived oils and fats, long chain esters, and generally any organic material that contains hydrocarbons, having carbon chain length preferably from about C6 up to about C40. These additional materials may be blends from natural or synthetic feedstocks or may be pure chemicals.
[0035] The gelled gasoline taught by the present invention may contain gasoline additives. Additives are gasoline-soluble chemicals that are mixed with gasoline to enhance certain performance characteristics or to provide characteristics not inherent in the gasoline. Typically, they are derived from petroleum-based raw materials and their function and chemistry are highly specialized. They produce the desired effect at the parts-per-million (ppm) concentration range. (One ppm is 0.0001 mass percent.)
[0036] Oxidation inhibitors, also called antioxidants, are aromatic amines and hindered phenols. They prevent gasoline components from reacting with oxygen in the air to form peroxides or gums. They are needed in virtually all gasolines, but especially those with a high olefins contents. Peroxides can degrade antiknock quality and attack plastic or elastomeric fuel system parts, soluble gum can lead to engine deposits, and insoluble gums can plug fuel filters. Inhibiting oxidation is particularly important for fuels used in modern fuel-injected vehicles, as their fuel recirculation design may subject the fuel to more temperature and oxygen-exposure stress.
[0037] Corrosion inhibitors are carboxylic acids and carboxylates. The facilities—tanks and pipelines—of the gasoline distribution and marketing system are constructed primarily of uncoated steel. Corrosion inhibitors prevent free water in the gasoline from rusting or corroding these facilities. Corrosion inhibitors are less important once the gasoline is in the vehicle. The metal parts in the fuel systems of today's vehicles are made of corrosion resistant alloys or of steel coated with corrosion-resistant coatings. In addition, service station systems and operations are designed to prevent free water from being delivered to a vehicle's fuel tank.
[0038] Metal deactivators are chelating agents—chemical compounds which capture specific metal ions. More-active metals, like copper and zinc, effectively catalyze the oxidation of gasoline. These metals are not used in most gasoline distribution and vehicle fuel systems. However, when they are present, metal deactivators inhibit their catalytic activity.
[0039] Demulsifiers are polyglycol derivatives. An emulsion is a stable mixture of two mutually insoluble materials. A gasoline-water emulsion can be formed when gasoline passes through the high-shear field of a centrifugal pump if the gasoline is contaminated with free water. Demulsifiers improve the water separating characteristics of gasoline by preventing the formation of stable emulsions.
[0040] Antiknock compounds are lead alkyl, tetraethyl lead (TEL) and tetramethyl lead (TML) and methylcyclopentadienyl manganese tricarbonyl (MMT). Antiknock compounds increase the antiknock quality of gasoline. Because the amount of additive needed is small, they are a lower cost method of increasing octane than changing gasoline chemistry. Gasoline containing tetraethyl lead was first marketed in 1923. The average concentration of lead in gasoline gradually was increased until it reached a maximum of about 2.5 grams per gallon (g/gal.) in the late 1960s. After that, a series of events resulted in the use of less lead: new refining processes which produced higher octane gasoline components, steady growth in the population of vehicles requiring unleaded gasoline, and EPA regulations requiring the reduction of the lead content of gasoline in phased steps beginning in 1979. The EPA completely banned the addition of lead additives to onroad gasoline in 1996 and the amount of incidental lead may not exceed 0.05 g/gal.
[0041] MMT was commercialized in 1959 and was used in gasoline alone or in combination with the lead alkyls. The Clean Air Act Amendments of 1977 banned the use of manganese antiknock additives in unleaded gasoline unless the EPA granted a waiver. MMT continued to be extensively used in unleaded gasoline in Canada. In 1996, after several waiver requests and court actions by the manufacturer, the courts ordered the EPA to grant a waiver for MMT. Its use is limited to a maximum of 0.031 g/gal. California regulations continue to ban the addition of manganese to gasoline.
[0042] Anti-icing additives are surfactants, alcohols, and glycols. They prevent ice formation in the carburetor and fuel system. The need for this additive is disappearing as older-model vehicles with carburetors are replaced by vehicles with fuel injection systems.
[0043] Dyes are oil-soluble solids and liquids used to visually distinguish batches, grades, or applications of gasoline products. For example, gasoline for general aviation, which is manufactured to different and more exacting requirements, is dyed blue to distinguish it from motor gasoline for safety reasons.
[0044] Markers are a means of distinguishing specific batches of gasoline without providing an obvious visual clue. A refiner may add a marker to their gasoline so it can be identified as it moves through the distribution system.
[0045] Any of these additives may be used in the reduced vapor pressure pseudoplastic gelled fuels and solvents taught by present invention without departing from the scope of the invention.
EXAMPLES
[0046] The following are examples of gelled fuel and solvent made according to an embodiment of the present invention. These examples should be taken as illustrative of the invention and not as limiting its scope. All values are in weight percent.
[0047] Gelled Hydrocarbon Solvent
[0048] The first example is a gelled solvent. The base hydrocarbon solvent is Penreco Conosol C-145. This solvent is made and sold by Penreco of Houston, Tex. Conosol C-145 is a high-purity, low-odor aliphatic solvent composed primarily of C 10 -C 13 cycloparaffinic and isoparaffinic hydrocarbons. It is a low-toxicity product that contains less than 0.5% aromatics, and it has a higher solvent strength than competitive 140+ flash aliphatic solvents.
[0049] The Conosol solvent is gelled by the addition of 9.5 weight percent of Kraton 1702 diblock copolymer and 0.5 Kraton 1650 triblock copolymer. These polymers are produced and sold by Kraton Polymers of Houston, Tex.
[0050] The control solvent and the gelled solvent were then tested for volatility by an evaporation test conducted at the Penreco Technology Center in the Woodlands, Tex.
[0051] Evaporation Test Procedure
[0052] Instruments: Square glass dish 4″/4′/1″ (2); Fume hood; Room thermometer; Scale that can accurately measure 100 g product
[0053] Materials: Conosol C-145, Gelled Conosol
[0054] Procedure: 1. Weigh 100 g of Conosol C-145 directly in a square glass dish previously tarred. Repeat with gelled Conosol.; 2. Record products' weight and ambient temperature. 3. Place the two dishes side-by-side in the fume hood. 4. Pull the dishes out and weigh them every day for the two weeks. 5. Record products' weight and ambient temperature. 6. After the two weeks, when the evaporation rate has slowed down, weigh the dishes only once a week. 7. Record products' weight and ambient temperature.
[0055] The results of this experimental example is shown in Table 2 below and is presented graphically in FIG. 1 .
[0000]
TABLE 2
Solvent
Gelled Solvent
Day
Weight loss percentage
Weight loss percentag
0
0
0
1
9.73
7.24
2
19.27
14.48
3
25.81
20.32
4
29.36
23.86
5
34.17
27.78
6
40.86
32.61
7
44.86
37.17
8
46.72
39.72
9
50.84
43.05
10
55.1
49.47
11
12
61.29
52.68
13
63.13
55.13
14
68.3
59.93
15
66.83
58.23
16
17
18
19
75.56
68.09
20
78.49
69.7
21
79.14
71.87
22
23
83
74.85
24
83.83
75.48
25
86.45
80.6
26
87.51
78.98
27
88.25
79.64
28
29
90.28
81.44
30
31
32
33
92.92
83.4
34
35
36
37
96.46
85.67
38
39
40
41
42
43
98.88
87.5
44
45
46
47
99.65
88.07
[0056] The gelled solvent is shear thickening, but it remains pourable and flowable and needs no in line gel degrading to be used in industrial processing. The amount of triblock copolymer can be from about 0.10 to about 3.0 weight percent.
[0057] Gelled Fuel
[0058] The second example is a gelled fuel—gasoline v. ungelled gasoline. This test was conducted by Intertek Testing Services—Caleb Brett of Houston, Tex. according to ASTM D323, the Reid Vapor Pressure test.
[0059] Materials: Gasoline: Lab ID # 1004-2-0; Gelled Gasoline: Lab ID # 1004-2-1
[0060] The gelled gasoline was prepared by adding 10 weight percent of Kraton 1702 diblock copolymer to the base gasoline in a cold mix.
[0061] Test Procedure Reid Vapor Pressure ASTM D323; Vapor Pressure Test Results: Gasoline: 10.30 psi; Gelled Gasoline: 9.50 psi.
[0062] The gelled gasoline is pseudoplastic and shear thinning. At a shear rate of 25 the viscosity is 1.456; at shear rate of 50, the viscosity is 1.185; at a shear rate of 75, the viscosity is 1.062; and at a shear rate of 100, the viscosity is 1.019. Please see FIG. 3 for a graphical presentation of these results.
[0063] While the invention has been described with respect to a limited number of embodiments, the specific features of one embodiment should not be attributed to other embodiments of the invention. No single embodiment is representative of all aspects of the inventions. In some embodiments, the gel compositions may include numerous compounds not mentioned herein. In other embodiments, the gel compositions do not include, or are substantially free of, any compounds not enumerated herein. Moreover, variations and modifications therefrom exist. For example, various additives may also be used to further enhance one or more properties of the gel compositions and fuels or solvents made therefrom. Cross-linking within the gel may be either enhanced or reduced, as desired, by physical or chemical methods in order to modify the properties of the composition. It should also be understood that uses of the gel compositions are not limited to retail fuel or solvent products, but also encompass industrial solvents and fuels. While the processes are described as comprising one or more steps, it should be understood that these steps may be practiced in any order or sequence unless otherwise indicated. These steps may be combined or separated. Finally, any number disclosed herein should be construed to mean approximate, regardless of whether the word “about” or “approximate” is used in describing the number. The appended claims intend to cover all such variations and modifications as falling within the scope of the invention. The appended claims intend to cover all such variations and modifications as falling within the scope of the invention. | The present invention relates generally to gelled fuels and solvents. Specifically the invention relates to gel thickeners that reduce vapor pressure in fuels and solvents and are shear thinning (pseudoplastic or thixotropic) or are shear thickening and remain pourable and flowable. Still more specifically, the invention relates to nonaqueous gels made with diblock copolymers that reduce the Reid Vapor Pressure of gelled gasoline and lower the total volatility of gelled hydrocarbon solvents. These gels may contain secondary amino acid or triblock polymer gelling agents. The invention includes gel compositions and methods of making gels. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to electronic read/write memories, and, more particularly to such memories that can operate as first-in/first-out (FIFO) shift registers.
Using the common vertical metaphor, a FIFO shift register includes a control section which directs input data to a data "top" cell. The "top" cell is more precisely characterized as the bottommost cell which is vacant, that is, without valid data; all cells below this "topmost" cell are occupied with data. In effect, such a FIFO is a variable length shift register, the length of which is always the same as the data stored within. Thus, when data is "pulled" from the FIFO, each data bit shifts down one cell, as does the top cell position.
FIFO shift registers are commonly used to buffer and interface between two systems with incommensurate timing characteristics. They are often included in devices such as tape recorders, electronic typewriters and word processors.
For example, FIFO shift registers can be used to interface the analog and digital subsystems of the read circuitry in a high-performance tape drive system. In such a system, data is typically recorded as on parallel tracks of flux levels on a magnetic tape. The tape is passed over a read head which converts the magnetic flux levels of each track into analog electrical signals. These analog electrical signals are then digitized and fed into read/format circuitry for decoding.
While the timing within the read/format circuitry can be precisely synchronized according to a system clock, it is not a trivial matter to coordinate this digital circuitry with the incoming analog signal tracks, and to coordinate the individual signal tracks with each other. The timing of the data in the form of flux reversals on the tape is subject to the vagaries of mechanical speed fluctuations, tape or head misalignment, and tape deformation. Thus, the individual data tracks can be skewed with respect to each other and generally bear no intrinsic relation to the synchronization governing the read/format circuitry.
In order to interface the analog and digital circuits, each track can be processed by a phase locked loop, a FIFO shift register and de-skew circuitry. Each phase locked loop samples and assigns digital values to segments of the incoming analog signal. The phase locked loop also determines which samples are valid, i.e. represent a single bit of data, rather than a transition between two bits. In accordance with such determination, the phase locked loop determines when "push" commands are issued for the FIFO to accept a data input. The de-skew circuitry looks for certain timing marks written into the data tracks and can issue or withhold "pull" commands which withdraw data from the FIFO and cause the contents to shift down. Thus, the FIFO shift registers serve to buffer the interface between the analog and digital subsystems of the read circuitry.
However, available FIFO shift register designs can constrain system performance due to cost, reliability and speed limitations. Most of these limitations are related to the difficulty of implementing current FIFO designs in very large scale integrated (VLSI) circuits. VLSI technology provides for very cost effective manufacture of complex circuits. This translates into significant savings with respect to simple circuits that can be integrated into a larger system implemented on a VLSI device. Likewise, a circuit included in a VLSI device can obtain speed advantages due to the short electrical paths involved and reliability advantages due to the minimization of separate interfacing manufacturing steps.
However, the reliability of VLSI devices is dependent on the manufacturer's ability to discard defective devices. This, in turn, requires that the designs implemented in VLSI be readily testable. Testability is in large part dependent on the design being entirely synchronous.
Thus, intelligent circuit design involves integrating circuits synchronized to a common clock on a monolithic device, such as a read/format chip, while leaving asynchronous components off. Thus, it can be said that a synchronization boundary limits which devices can take advantage of VLSI. Available FIFO shift register designs are asynchronous and thus must lie outside a synchronization boundary. Likewise, components separated from a synchronous subsystem by such a FIFO shift register are outside the synchronization boundary so that it is difficult to obtain advantages by integrating them into a main system chip.
Thus, current FIFO shift register designs cannot reliably take advantage of VLSI technology; this limitation extends to other components, e.g., those upstream from a FIFO shift register in tape recorder read circuitry. A related disadvantage is that it is difficult to coordinate the operation of FIFOs arranged in parallel, as is often the case in tape drive read circuitry. In addition, FIFO shift registers can delay system operation during the time it takes for a data bit to "bubble-through" to the top cell. Thus, there is a need for a FIFO shift register, which provides for higher speed operation, integration into VLSI devices, and coordination with other FIFO shift registers arranged in parallel.
SUMMARY OF THE INVENTION
A FIFO shift register includes means for directly injecting an input into any selected cell. This avoids the delays due to bubble-through time, and, more importantly, permits the FIFO to operate synchronously. Thus, the present invention provides for a FIFO shift register that can be integrated into a monolithic VLSI device. Furthermore, the operation of such a FIFO shift register can be readily coordinated with the operation of similar devices arranged in parallel.
As with comparable conventional devices, the present FIFO shift register includes a serially arranged set of read/write memory cells. This set includes a FIFO bottom cell, from which data exits the FIFO, and which, if any data is held by the FIFO, holds a data bit. The set also includes a FIFO top cell, which only holds a valid data bit when the FIFO is full. Each cell other than the FIFO top cell has an associated predecessor cell, and each cell other than the FIFO bottom cell has an associated successor cell. Means are provided for each cell having an associated successor cell to transfer the former's contents to the latter.
In accordance with the present invention, each cell of the FIFO shift register can accept an input from a parallel data input line. Input manager means are provided for determining, for each cell, whether the next transfer is to be from a predecessor cell or from the parallel data input line. Each cell can be clocked to provide synchronous operation. Several such FIFO shift registers can be operated synchronously in parallel, as desired.
The input manager can be implemented as a series of input manager cells in one-to-one correspondence with the data cells. Each input manager cell stores a bit indicating whether the respective data cell includes valid data or not. This information is used to control input selection for the respective data cell, and its successor data cell, if any. The specific determinations are responsive to "push" and "pull" signal inputs to the FIFO shift register. Further details and advantages are apparent in view of the drawings and detailed description below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of a synchronous bank of two FIFO shift registers in accordance with the present invention.
FIG. 2 is a schematic showing two of the cells of one of the FIFO shift registers of FIG. 1.
FIG. 3 is a timing diagram for one of the FIFO shift registers in FIG. 1.
FIG. 4 is a block diagram of the read circuitry for a tape drive incorporating FIFO shift registers in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A FIFO shift register bank 99 includes two FIFO shift registers 100 and 200, as illustrated in FIG. 1. Each FIFO shift register 100, 200 comprising a series of cells 101-132, 201-232. Flux data can be injected directly into each cell by means of flux data in (FDIN) lines which connect to parallel in-ports (PIN) of each cell. Additionally, the FIFO shift registers 100 and 200 can be driven by a common clock (CLOCK) for synchronous operation.
The operation of the FIFO shift registers 100 and 200 is explained in relation to the interaction between two adjacent cells 103 and 104, as detailed in FIG. 2. Cell 102 is the "next" cell referred to in FIG. 2, while cell 105 is the prior cell. Data flows toward cells with lower numbers, while the FIFO shift register fills towards the cells with higher numbers.
Cell 103 includes a data cell A 143 and an input manager cell A 153, and, correspondingly, cell 104 includes a data cell B 144 and an input manager cell 154. ("A" and "B" can be considered mnemonics for "above" and "below", respectively.) Each data cell 143, 144 includes ten ports. Conventionally, push (PSH), pull (PL), data input (SIN), data output (SOUT), clear (CL), and test (TST) ports are provided. In accordance with the present invention, clock (CLK), parallel in (PIN), data valid here (DVH) and data valid above (DVA) ports are also provided.
These additional ports are controlled, directly or indirectly by the input manager cells 153 and 154. For example, the value at the DVH port of data cell B 143 is the contents of input manager B 153, whereas the value at the DVA port of data cell B 143 is the same as the contents of input manager A 154. For any given data cell, the source of the next data bit to be stored is determined by the values at DVA and DVH in conjunction with received PSH and PL inputs. The source can be either the serial in (SIN) or the parallel in (PIN) of the cell.
When the clear (CL) signal is activated, all data cells are initialized to "0" and all input managers are initialized to "1". A "1" in an input manager cell is used to signify that the value stored by the associated data cell does not reflect valid data. Thus, the input managers store the complement of validity indicators, hence the denomination "V*". With qualification as detailed below, the effect of a "1" in the input manager is to cause the associated cell to accept data through its parallel in (PIN) rather than its serial in (SIN).
The input managers of a given FIFO shift register constitute a bi-directional shift register. A push, without a concurrent pull, causes the contents of this bi-directional shift register to shift up (or left, in FIGS. 1 and 2) one cell. For example, the "1" stored in input manager B 153 can be transmitted through its V* port to the INB port of input manager A 154. Conversely, a pull without a push causes a downward shift in input manager contents. For example, the "0" stored in input manager A 154 can be transmitted through its V* port to the INA port of input manager B 153. Concurrent pull and push signals result in no shift in input manager contents.
Referring to FIG. 1, the INB of bottom cell 101 is tied to ground. Thus, "0s" are drawn into the bidirectional shift register constituted by the input managers whenever a push without a pull is implemented. Thus, as data is stored in the FIFO shift register 100, the "1s" shift up, and "0s" fill the vacancies below. Correspondingly, the INA in-port of the top cell 132 is tied to a voltage high VDD, so that "1s" are input as the bi-directional shift register shifts down in response to pull commands. Note that the serial in (SIN) of this same top cell is tied to ground, so that, normally, the only data input to the FIFO is through the parallel in-ports (PIN).
This arrangement provides three alternative states for the bi-directional shift register. First, all input managers can store "1s", signifying that there is no valid data in the FIFO shift register, as is the case at initialization. Second, all input managers can store "0s"; this signifies that an overflow could have occurred, and accordingly, the V* out-port generates an overflow (OVER) signal, which is treated as an error signal. Third, there can exist a boundary, or "top", above which all input managers are filled with "1s" and below which all input managers are filled with "0s". There are no other normal steady state possibilities.
Consider the case where input manager A 154 contains a "1" and input manager B 153 contains a "0", with reference to FIG. 2. If a push is issued, the "0" stored in input manager B 153 provides that the associated data cell B is not to accept new data from either of its in-ports. The "1" in input manager A 154, on the other hand, causes the associated data cell A 144 to accept a data input through its parallel in-port PIN. The push command also shifts the contents of the input managers one cell up so that both input managers illustrated in FIG. 3 would contain "0 s". Thus, if the next command is a push, neither data cell would accept an input.
When a pull is issued, each data cell is governed by the value at its DVA port. Assuming again that the illustrated input managers 153 and 154 contain different values, when a pull is issued, the "1" at the DVA port of data cell B 143 causes it to accept data via its parallel in (PIN). If on the other hand, input manager A 154 contained a "0", indicating that data cell A had valid data, data cell B would accept that valid data via its serial in (SIN) port. When the pull is issued without a push, the values stored in the input managers shift one cell down. Thus, the "1" in input manager A exits its V* port and is received at the INB of input manager B.
When pull and push are issued concurrently, there is no change in the input manager contents. The value at the DVA port of a data cell determines through which port that data cell will accept its next data bit. Note that the input manager output V* has four destinations, the DVH, "data valid here", port of the associated data cell, the DVA, "data valid above", port of the data cell which is the immediate successor to the associated data cell, the INA, "input from above", of the immediate successor input manager, and the INB, "input from below", of the immediate predecessor input manager.
The operation of this pair of cells 103 and 104 can be characterized by the following program in MADL, the Multi-Level Architectural Language for system simulation, developed by Hewlett-Packard Company:
______________________________________BLOCK BEH BLOCK BEH dcb(INPORTBIT pin;BIT sin;BIT psh;BIT dva;BIT pl;BIT dvh;BIT clk;BIT cl;BIT tst;OUTPORTBIT sout);STRUCT temp,tempout;BEGIN #dcbIF clk = % b1 THEN #Phase 1BEGINif cl = % b1 then temp: = % b0else if tst = % b1 then temp: = sin;else if dvh = % b1 then temp: = pin;else if p1 = % b1 thenbeginif psh = % b1 && dva = % b1 thentemp: = pin;elsetemp: = sin;end;else temp: = tempout;END;ELSE #Phase 2BEGINtempout: = temp;sout: = temp;END;END; #dcbBLOCK BEH imb(INPORTBIT inb;BIT ina;BIT clk;BIT set;BIT tst;BIT pl;BIT psh;OUTPORTBIT v*;STRUCT temp, tempout;BEGIN #imbIF clk = % b1 THEN #Phase 1BEGINif set = % b1 then temp: = % b1;else if tst = % b1 then temp: = ina;else if pl = % b1 && psh = % b1then temp: = tempout;else if p1 = % b0 && psh = % b0then temp: = tempout;else if pl = % b1 && psh = % b0then temp: = ina;else if p1 = % b0 && psh = % b1then temp: = inb;END;ELSE #Phase 2BEGINtempout: = temp;v*: = temp;END;END; #imb(PROGRAM END)______________________________________
This program and the accompanying drawings are simplified in that in most cases, the signals are composite. For example, the clock signal is implemented as ten clock signals. The clock is a two phase clock, so that phase 1 and its complement, and phase two and its complement are provided. An additional phase 1 clock is provided due to routing constraints to the data cells. A duplicate set of signals is then directed to the input manager cells. Likewise, most of the other signals include the listed signal and its complement.
The operation of FIFO shift register 100 of FIG. 1, is further explained in connection with the timing diagram of FIG. 3 in which CLK[0] is the clock's phase 1 input to the FIFO shift register, CLK [1] is the clock's phase 2 input, CL is the "clear" input, PSH is the "push" input, PL is the "pull" input", FDIN is the flux data input, FDOUT is the "flux data out" of the FIFO shift register, and EMPTY is the "empty" output.
The sequence depicted in FIG. 3 is as follows:
1. (0-0.75 μS) During the first three cycles, clear is asserted and the FIFO shift register is forced into an empty state. Clear does not need to be asserted for this long. One cycle is enough.
2. (0.75-1.0 μS) Then, a "1" is pushed. Empty goes away before the next clock cycle.
3. (1.0-1.5 μS) Then a "0" is pushed.
4. (1.25-1.5 μS) Then, a pull is asserted. Note that the "1" at the output disappears at the end of phase 1 of the clock (clk[0] high) and is replaced by the next bit in the FIFO shift register, a "0".
5. (1.5-1.75 μS) Another pull is asserted. The "0" disappears at the end of phase 1 of the clock as in the previous pull. Empty goes true at the same time, indicating that the value of "FDOUT" is not valid.
6. (1.75-2.0 μS) Then, another "1" is pushed, empty goes false.
7. (2.0-2.25 μS) Then, a "0" is pushed simultaneously with pull being asserted. Note that the "1" that was just pushed is removed from the FIFO shift register output and is replaced by the next bit, a "0". Empty stays low, because the "0" at the output is valid, and has not yet been removed.
8. (2.25-2.5 μS) Another "1" is pushed.
9. (2.5-2.75 μS) A "0" is pushed simultaneously with pull being asserted. This time, the "0" is taken from the output and replaced by the "1" put in after it. As this procedure finishes, the FIFO shift register contains two bits: a "1" followed by a "0".
In order to facilitate interfacing, the FIFO shift registers 100 and 200 of FIG. 1 provide four output signals: "FDOUT" is a convention flux data out signal; "EMPTY" indicates that no valid data is available for output, and is generally used by interfaced devices to inhibit the assertion of a pull; "OVER" indicates all cells have valid data, and, therefore, that an overflow error may have occured; and "FULL" is used to initiate actions to be taken before an overflow error is encountered. In the illustrated FIFO shift registers 100 and 200 of FIG. 1, "FULL" is the V* output of the third to last cell, e.g. cell 130 in FIFO shift register 100.
These "FULL" or "almost full" signals are combined across FIFO shift registers in FIFO bank 99. The FULL output from cell 130 is directed to gate 161 which stores the logic sum of its FULLIN input, which is tied to ground, and the inverse of the V* output of cell 130. This sum is available at the FULLIN input of gate 162 where it is logically ORed with the inverse of the V* output of cell 230. The result is an "any full?" signal which indicates whether either of the two FIFO shift registers is full. Accordingly, three full signals are made available for interfacing, one for each FIFO shift register 100, 200, and a logically ORed signal that signifies if either of the shift registers is full.
As incorporated in the tape drive read circuitry 300 of FIG. 4, nine FIFO shift registers provide nine individual FULL signals and an ORed composite, yielding a 10-bit signal at 301. One FIFO shift register 302 is shown with the "OVER", push, pull, empty, and flux data input and output lines.
The flux data input to the FIFO shift registers of FIG. 4 is shown originating from a 9-track magnetic tape 303 passing over a read head 305. The read head 305 converts magnetic flux levels to electrical signal levels and directs them to analog read circuitry 307. The nine channels of flux data output from the analog read circuitry are digitized by a bank 309 of nine phase locked loops (PLL) 311.
The PLL bank 309 provides nine channels of multiplexed flux data and validity signals. Upon demultiplexing, an active validity signal is treated as a "push" signal to the respective FIFO shift register. That is, on one half cycle, a validity signal is issued which indicates whether or not the data represented on the following half cycle, on the same line, is to be pushed into the respective FIFO shift register. The timing for this clock cycle is governed and indicated by a phase/select signal provided by the incorporating read system and synchronized to the main system clock of the read circuitry.
The phase/select and flux data/validity signals are input to a monolithic VLSI de-skew/read circuit 313. An included demultiplexer 315 filters the incoming data/validity signal to filter out invalid data, and issues push (PSH) signals to the FIFO shift registers 302 as valid data is transmitted on a track-by-track basis.
The de-skew/read circuit 313 is governed by a master clock, not shown because of its pervasiveness. The master clock is the source of the clock input to the FIFO shift registers as well as to the de-skew and mark detect section 317 and the read/format section 319 of the de-skew/read circuit 313. Additionally, the master clock provides synchronization of the phase/select signal from the PLL bank 309.
While the 9-tracks of flux data output from the PLL bank 309 are synchronized with respect to the master clock, they are not generally synchronous with respect to each other. Relative mechanical misalignment of the read head and the tape path, and distortions of the tape due to drive forces and fatigue cause bits originally written synchronously to by read at slightly different times.
At the high bit densities used in high-performace tape drives, these small time differentials can cause, for example, bit one of track one to be concurrent with bit 3 of track 5. In order to be able to reliably decode data being read from a tape, de-skew circuitry is provided. In the illustrated embodiment, the de-skew and mark detect section identifies data block boundaries and synchronization marks written onto the tape on each track.
When a predetermined mark is found in one track, the de-skew circuitry disables the normally active "PULL" signal. Since this prevents data from exiting a FIFO shift register without preventing data from entering, the respective FIFO shift register starts to fill. As the FIFO shift register is filling, the de-skew and mark detect circuitry seeks corresponding marks in the other tracks. Assuming the sought mark is found for all tracks, or a sufficient number of tracks for error correction purposes, before any FIFO shift register issues a FULL signal, this procedure permits successful deskewing. In the event insufficient sought marks are detected prior to one of the tracks filling, then the de-skew circuitry performs further corrective action in response to the generated "any full", "this track full" and mark detects and in accordance with the implemented de-skew strategy.
When the attempt to locate a mark in sufficient tracks fails, a validity strobe is held inactive and the READ/FORMAT section discards the received flux data input. Otherwise, the READ/FORMAT section formats the valid input, discards non-data flux inputs, such as synchronization and other marks, and corrects the received data according to implemented error correction schemes, and outputs 8-bit data, which can include a parity bit, to a system processor (not shown). An end of data (EOD) signal is also provided to mark data boundaries for the processor.
The disclosed FIFO shift registers are readily adapted for alternative modes of operation by virtue of the fact that the manager cells can be read and programmed. For example, the contents of the input manager cells can be read by capturing the V* outputs for each input manager cell, or by stepping out the commands serially by issuing PSH without PL commands and monitoring the OVER signal, or by issuing PL without PSH signals and serially monitoring the EMPTY output.
Likewise, the input manager cells can be programmed by controlling the level at INB of the bottommost input manager cell, e.g. 101, as PSH without PL signals are issued, or by controlling the level at INA of the topmost input manager cell, e.g. 132, as PL without PSH are issued. By programming the input manager cells and by tying PSH and PL signals together, a programmable length shift register is provided.
The fact that the FIFO shift register structures disclosed provide for alternative use as programmable and readable fixed length shift registers can enhance the flexibility of an incorporating drive system. For example, at lower flux densities, dynamic skew can be insignificant, so that only static skew, which can be induced by stable mechanical misalignments, need be addressed. Thus, a calibration tape for a given flux density can be used to determine the skew profile of a particular tape drive system. This skew profile can be read from the respective input manager cells, and stored. When a normal (non-calibration) tape is loaded, this profile can be programmed into the respective input manager cells so that each shift register introduces the delay in its track necessary to ensure that the data is aligned across tracks at the shift register bank output. Of course, there are many other possible uses for the ability to read and program the shift registers.
Due to the provision for synchronized operation of the disclosed FIFO shift register, it can be implemented as shown as part of the monolithic VLSI de-skew/read circuit 313. As a bonus advantage, the demultiplexer, which if conventional FIFO shift registers were used would be excluded from the VLSI chip, can be and is brought within the synchronization boundary 315.
Additionally, the provision for clocked direct injection transfers removes uncertainty in determining when a bit is to be available at output. Thus, during normal operation in the absence of skew, bits input to a FIFO bank concurrently can be removed concurrently at a predictable time. In other words, the present invention provides that data synchronized at the input of the FIFO bank is synchronized at its output. This relieves the system of the need to introduce delays to allow the bits to "line-up" at the output of the FIFO bank, or, in the alternative, to include additional circuitry to correct an asynchronous output.
As a further advantage of the present invention, the direct injection of data into the next available vacancies minimizes "bubble-through" delays. Thus, the disclosed FIFO shift register can easily match the speeds of the interfacing circuitry.
The invention provides for further advantages in other modifications and variations apparent to those skilled in the art. The invention is adaptable to FIFO shift registers of two or more bits in depth, and parallel FIFO banks of any dimension. Furthermore, alternative modes of operation can be provided for by modifying the disclosed circuitry or by providing the appropriate outboard logic. These and other modifications and variations are provided for by the present invention, the scope of which is limited only by the following claims. | A FIFO shift register (100) includes a parallel data in-port (PIN) to each of its cells (101-132) and a means for managing input to determine for each cell whether it is to receive data and, if so, whether through its conventional serial in-port (SIN) or through its parallel in-port. The input manager comprises a bidirectional shift register of input manager cells arranged in one-to-one correspondence with data cells. A one-bit validity indicator stored within a given input manager cell is logically combined with asserted PUSH and PULL signals to determine the source of data for the associated data cell and its immediate successor. This arrangement not only provides greater speed by minimizing bubble-through time, but permits the FIFO shift register to be clocked. This capacity for synchronous operation permits ready VLSI implementation with concomitant advantages in economy, reliability and speed. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a magnetic resonance imaging apparatus, of the type having a mobile (movable) gradient coil unit.
[0003] 2. Description of the Prior Art
[0004] Magnetic resonance is a known technique for generating images of the inside of a body of an examination subject. For this purpose, rapidly switched gradient fields are superimposed onto a static basic magnetic field in a magnetic resonance apparatus, the static basic magnetic field being generated by a basic field magnet. The magnetic resonance apparatus also has a radio-frequency system which irradiates radio-frequency signals into the examination subject in order to trigger magnetic resonance signals and which accepts the triggered magnetic resonance signals. Magnetic resonance images are produced on the basis of the magnetic resonance signals.
[0005] The magnetic resonance apparatus has an examination chamber in which a port of the examination subject to be imaged is positioned for producing magnetic resonance images of the area to be imaged. For this purpose, the magnetic resonance apparatus normally has at least one movable positioning device on which the examination subject is borne. Positioning of the area to be imaged in the examination chamber is possible by displacing the positioning device with the examination subject thereon.
[0006] For example, U.S. Pat. No. 5,185,576 discloses a local gradient coil unit that is combined with a local radio-frequency antenna. The local gradient coil unit has an integrated local radio-frequency antenna is configured for a specific area of the examination subject such as a head of a patient. In contrast to a firmly installed gradient coil system which is dimensioned for the entire patient, the local gradient coil unit, therefore, can be smaller which has advantages concerning obtainable gradient intensities and power requirements with respect to a gradient amplifier feeding the gradient coil unit. The local gradient coil unit having an integrated local radio-frequency antenna can be mounted on the positioning device such that the local gradient coil unit does not move toward the positioning device even given the operation of the magnetic resonance apparatus and the forces acting on it.
[0007] Furthermore, U.S. Pat. No. 5,311,134 discloses a magnetic resonance apparatus having a cylindrical stationary base unit with a basic field magnet and a gradient coil system that cannot be displaced vis-a-vis the basic field magnet. The magnetic resonance apparatus has a track-like guiding device which is partially arranged in a hollow space of the base unit, and extends beyond the hollow space and on which an essentially cylindrical movable gradient coil unit can be displaced, whereby an antenna unit is firmly connected to it in one embodiment. The magnetic resonance apparatus also has a patient bed with which the patient thereon cannot only be positioned in the hollow space of the base unit but also in a hollow space of the gradient coil unit.
SUMMARY OF THE INVENTION
[0008] An object of the invention is to provide an improved magnetic resonance apparatus having a mobile gradient coil unit wherein the gradient coil unit can be handled in a simple manner.
[0009] This object is achieved in accordance with the present invention in a magnetic resonance apparatus has a gradient coil unit, which can be displaced on a guide device disposed inside an examination chamber of the magnetic resonance apparatus, an auxiliary device that is displaceable in relation to the examination chamber, and which can be docked on the guide device in order to extend the displacement of the gradient coil unit. The extension device may continue the course of the guide device along a curved path outside of the examination chamber. A positioning device may be displaced on the guide device, extended by the extension device, to displace a subject relative to the examination chamber.
[0010] The inventive gradient coil unit, whose weight can be up to 250 kg, does not have to be lifted for inserting or removing the gradient coil unit into or from the examination chamber given a change between an image acquisition operation with or without the mobile gradient coil unit. Since the gradient coil unit does not have to be lifted, a crane or lift, which is usually provided therefor, is not necessary. Rather, the change can occur by smoothly displacing the gradient coil unit on a horizontal plane.
[0011] In an image acquisition operation without the movable gradient coil unit, the gradient coil unit can be positioned next to an opening of the examination chamber such that a maximum extension of a positioning device through this opening is not impaired. Furthermore, additional space behind the opening is not necessary since the gradient coil unit is parked next to the opening—in contrast to the positioning device that is maximally extended through the opening. Therefore, the minimum distance between the opening and the wall of a setup room or a shielding cabin facing the opening is not enlarged. The unimpaired maximum extension of the positioning device is particularly important with for angiography of peripheral vessels of a patient and/or for obtaining images of the entire body, given magnetic resonance apparatuses having a short basic field magnet, in particular. In the inventive apparatus, in particular, the examination chamber can be easily accessed.
[0012] In an embodiment, an enlarged space must be provided behind the opening for a maximum extension of the positioning device through the opening of the examination chamber when the gradient coil unit is not used at the same time, however, a guiding device that is arranged in the examination chamber is used not only for the positioning device but also for the gradient coil unit.
DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 shows a horizontal longitudinal section through a magnetic resonance apparatus having an extension device for a guiding device of a movable gradient coil unit in accordance with invention.
[0014] [0014]FIG. 2 shows a horizontal longitudinal section through a magnetic resonance apparatus having a curved additional device for a guiding device of a movable gradient coil unit in accordance with invention.
[0015] [0015]FIG. 3 and FIG. 4 show horizontal longitudinal sections through a magnetic resonance apparatus having a movable auxiliary device for a movable gradient coil unit in accordance with the invention.
[0016] [0016]FIG. 5, FIG. 6 and respectively FIG. 7 show horizontal longitudinal sections through a magnetic resonance apparatus having a pivotable auxiliary device for a mobile gradient coil unit in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] As an exemplary embodiment of the invention, FIG. 1 shows a horizontal longitudinal section through a magnetic resonance apparatus having an extension device 16 . The magnetic resonance apparatus has an essentially cylindrical base unit 10 in whose hollow space an examination chamber 11 is arranged. The base unit 10 has a superconducting basic field magnet in order to generate a static basic magnetic field, a firmly installed gradient coil system in order to generate gradient fields and an antenna system, which is also firmly installed, for transmitting radio-frequency signals and for receiving magnetic resonance signals.
[0018] The magnetic resonance apparatus has a movable positioning device 18 for introducing the examination subject into the examination chamber 11 . The positioning device 18 can be completely moved out of the examination chamber 11 through an opening of the hollow space situated opposite an opening 12 (not shown in FIG. 1) and can be moved from there into the examination chamber 11 and can be maximally extended through the opening 12 up to the position shown in broken lines.
[0019] A guiding device 14 , which is continued beyond the examination chamber by the extension device 16 , is arranged in the examination chamber 11 of the magnetic resonance apparatus. The guiding device 14 and the extension device 16 serve as a glide path for the positioning device 18 and serve the purpose of guiding a movable gradient coil unit 15 on a horizontal plane prescribed by the devices 14 and 16 .
[0020] In order to generate gradient fields, the movable gradient coil unit 15 has at least one or up to three gradient coils and, depending on the utilization requirements, possibly has shielding coils, cooling and shim devices, which belong to the gradient coils, and can be combined with a local radio-frequency antenna. The electric connecting lines and, if present cooling supply lines, which are necessary for supplying the gradient coil unit 15 , are flexibly fashioned and are firmly connected to the gradient coil unit 15 and to a stationary part of the magnetic resonance apparatus.
[0021] The movable gradient coil unit 15 is cylindrically fashioned such that it can accept a head of a patient. For this purpose, the positioning device 18 is fashioned at the plane facing the gradient coil unit 15 such that it can be moved into a hollow space of the gradient coil unit 15 so that a patient correspondingly positioned on the positioning device 18 can be introduced with the head into the gradient coil unit 15 by displacing the positioning device 18 .
[0022] Given an image acquisition operation of the magnetic resonance apparatus without the gradient coil unit 15 and, as shown in FIG. 1, given a positioning device that is maximally extended through the opening 12 , a length of the extension device 16 is selected such that the extension unit 16 is still capable of carrying the gradient coil unit 15 in a position shown by a thick continuous line.
[0023] For an image acquisition operation using the gradient coil unit 15 and given a positioning device 18 which is only moderately introduced into the examination chamber 11 or which is completely moved out of the examination chamber 11 , the gradient coil unit 15 , from the position shown by a thick continuous line, is to be moved into the examination chamber 11 by a horizontal displacing along the extension device 14 and guiding device 16 and is to be fixed in the examination chamber 11 in a position shown by a thick dot-dash line. Subsequently, the head of the patient can be positioned in the gradient coil unit 15 by displacing the positioning device 18 with the correspondingly positioned patient.
[0024] In an exemplary embodiment, a local radio-frequency antenna, particularly for a head of the patient, can be introduced into the gradient coil unit 15 and is fashioned such it can be fixed on the positioning device 18 , so that the radio-frequency antenna, which is fixed on the positioning device 18 at the plane facing the gradient coil unit 15 , can be moved in and out of the gradient coil unit 15 , which is positioned in the examination chamber 11 , by displacing the positioning device 18 .
[0025] In a further exemplary embodiment, the gradient coil unit 15 is cylindrically fashioned having two recesses for accepting a head of a patient including his/her shoulders, so that a neck area of the patient can also be accepted instead of only imaging the head. German Patent 198 29 298 C2 describes such a gradient coil, however, it is not movable.
[0026] As another exemplary embodiment of the invention, FIG. 2 shows a horizontal longitudinal section through a magnetic resonance apparatus having a curved additional device 26 . The magnetic resonance apparatus has an essentially cylindrical base unit 20 that is configured corresponding to the one as shown in FIG. 1. An examination chamber 21 is arranged in a hollow space of the base unit 20 , whereby examination chamber 21 has a guiding device 24 for guiding a mobile gradient coil unit 25 within the examination chamber 21 . For the continuation of the guiding device 24 , the curved additional device docks on an opening 22 of the examination chamber 21 so that the mobile gradient coil unit 25 can be displaced on a horizontal plane defined by the additional device 24 and guiding device 26 .
[0027] For an operation of the magnetic resonance apparatus by using the movable gradient coil unit 25 , the gradient coil unit 25 is positioned as shown by a thick dash-dot line and is correspondingly fixed. For an operation without the gradient coil unit 25 , the gradient coil unit 25 is positioned as shown by a thick continues line and is correspondingly arrested. The additional device 26 , in particular, is fashioned such that a displaceable positioning device (not shown), which is moved inside through an opening of the hollow space (not shown) that is opposite the opening 22 , can be maximally extended through the opening 22 without impairment by the additional device 26 .
[0028] As a further exemplary embodiment of the invention, FIG. 3 and FIG. 4 show horizontal longitudinal sections through a magnetic resonance apparatus having an auxiliary device 36 . The magnetic resonance apparatus has an essentially cylindrical base unit 30 that is fashioned as shown in FIG. 1. An examination chamber 31 is arranged in a hollow space of the base unit 30 , whereby said examination chamber 31 has a guiding device 34 for guiding a movable gradient coil unit 35 .
[0029] In FIG. 3, the gradient coil unit 35 is fastened at the mobile auxiliary device 36 and the auxiliary device 36 , including the gradient coil unit 35 , is parked next to an opening 32 of the hollow space, so that the magnetic resonance apparatus can be operated without the gradient coil unit 35 and without impairment by the gradient coil unit 35 . Given this operating state, a positioning device (not shown) can be moved into and out of the examination chamber 31 without being restricted by the gradient coil unit 35 . The mobile auxiliary device 36 is fashioned such that it can be attached to the guiding device 34 for inserting or removing the gradient coil unit 35 , so that the gradient coil unit 35 can be displaced along a horizontal plane defined by the guiding device 34 and the auxiliary device 36 .
[0030] [0030]FIG. 4 shows the auxiliary device 36 being docked onto the guiding device 34 . After the gradient coil unit 35 has been detached with the auxiliary device, the gradient coil unit 35 can be moved onto the guiding device 34 into the examination chamber 31 smoothly by hand or motor-driven by the auxiliary device 36 and can be fixed there in a prescribed position.
[0031] As a further exemplary embodiment of the invention, FIG. 5 to FIG. 7 show horizontal longitudinal sections through a magnetic resonance apparatus having a pivotable auxiliary device 56 . The magnetic resonance apparatus has an essentially cylindrical base unit 50 that is fashioned as shown in FIG. 1. An examination chamber 51 is arranged in a hollow of the base unit 50 , whereby said examination chamber 51 has a guiding device 54 for guiding a mobile gradient coil unit 55 . The magnetic resonance apparatus also has a pivotable auxiliary device 56 , which for pivoting about a vertical axis, is connected to the base unit 50 via a hinge 57 . The gradient coil unit 55 can be fastened at the auxiliary device 56 . The auxiliary device 56 is fashioned in a pivotable manner such that the auxiliary device 56 can dock on the guiding device 54 in order to continue said guiding device 54 so that the gradient coil unit 55 can be displaced on a horizontal plane that is defined by the auxiliary and guiding device 54 and 56 . A particular advantage of the pivotable auxiliary device 56 is that the electric connecting lines, which are necessary for supplying the gradient coil unit 55 and possibly cooling supply lines, can be fashioned in a short manner.
[0032] [0032]FIG. 5 shows the auxiliary device 56 , which has the gradient coil unit 55 docked onto it, in a position pivoted next to an opening 52 of the hollow. This position is typical when the magnetic resonance apparatus is operated without using the gradient coil unit 55 . A positioning device (not shown), for example by using the guiding device 54 , can be displaced in the examination chamber 51 without impairment by the gradient coil unit 55 .
[0033] The auxiliary device 56 having the gradient coil unit 55 docked onto it, must be pivoted in the direction of the examination chamber 51 in order to operate the magnetic resonance apparatus with the gradient coil unit 55 . As an example, FIG. 6 shows an intermediate position of the pivot motion.
[0034] [0034]FIG. 7 shows the completed pivot motion with the auxiliary device 56 being docked onto the guiding device 54 . After the lock has been released, the gradient coil unit 55 , proceeding from the auxiliary device 56 can glide onto the guiding device 54 , can be displaced when gliding into the examination chamber 51 and can be fixed in the examination chamber 51 in order to subsequently operate the magnetic resonance apparatus with the gradient coil unit 55 .
[0035] Although modifications and changes may be suggested by those skilled in the art, it is the invention of the inventor to embody within the patent warranted heron all changes and modifications as reasonably and properly come within the scope of his contribution to the art. | A magnetic resonance apparatus has a gradient coil unit, which can be displaced on a guide device disposed inside an examination chamber of the magnetic resonance apparatus, an auxiliary device that is displaceable in relation to the examination chamber, and which can be docked on the guide device in order to extend the displacement of the gradient coil unit. The extension device may continue the course of the guide device along a curved path outside of the examination chamber. A positioning device may be displaced on the guide device, extended by the extension device, to displace a subject relative to the examination chamber. | 6 |
REFERENCE TO RELATED PATENTS
This invention is an improvement on the snow plow disclosed and claimed in Quenzi U.S. Pat. No. 4,658,519, which is incorporated herein by reference.
BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION
Numerous devices have been proposed in the past for detachably mounting a snow plow to the front of a vehicle, such as a truck. For the most part these require some vehicle attachment structure either to the bumper or have frame members such as a lift tower and light bar assembly which project in front of the bumper or, have a lift tower mechanism projecting upwardly between the bumper and the front grill of the vehicle. In most of these arrangements, the attachment structure remains on the vehicle during normal use (e.g., during non-plowing operations when the plow and its support frame are stored), and they, in effect, disable or in part disable the shock absorbing properties of the bumper and the operation of the bumper in actuating air bag deployment and the like. In addition, these attachment structures are generally unsightly and sometimes dangerous. In most cases, the prior art systems require fairly precise alignment (both vertically and horizontally) of parts on the plow itself and vehicle mounted parts during the attachment procedure. Very often, it requires two persons, one to drive the vehicle and, the other to either lift and make the alignment as the vehicle approaches to align the plow and the vehicle.
In addition, some recent mounting arrangements which seek to solve the bumper problems require a three-point connection to the vehicle, typically two spaced at a lower level below the bumper and one (or more) spaced above the bumper for connecting a lift mechanism to the plow frame to allow the frame to be lifted for transportation purposes. Moreover, such systems do not allow for slight horizontal and vertical misalignments between the attachment components permanently mounted on the vehicle and complementary attachment components on the plow support frame.
The present invention solves the above problems by providing a two-point coupling and suspension system in which a vehicle mounted attachment frame is secured to the frame of the vehicle and has a pair of spaced sockets which are positioned below and slightly behind the forward-most end surface of vehicle bumper when the vehicle mount attachment frame is mounted on the vehicle. The sockets include a first pair of reaction bearing surfaces aligned with and to the rear of the spaced sockets and a transverse latch bar forward of the reaction bearing surfaces. An intermediate support frame has a pair of rearwardly extending latching arms which extend in a rearward direction and have further reaction bearing surfaces for bearing against the respective ones of the first pair of reaction bearing surfaces when the plow has been lifted. The sockets have diverging plates which guide the rearwardly extending latching arms and thus horizontally aligns the arms with their respective sockets. Camming surfaces on the rearwardly extending latching arms engage a transverse latch bar and correct for vertical misalignments.
A support frame for supporting snow plow blade means has a rearward end pivotally connected to the intermediate frame for rotation about a horizontal axis. A lift mechanism is coupled between the intermediate support frame and the support frame for pivoting the support frame about the horizontal axis and for lifting the support frame and working implement off the ground such that the weight thereof is borne by the reaction bearing surfaces and the said pair of spaced socket means. One or more latch dogs are rotated by an over-center toggle linkage to lock the latch arms in their respective sockets.
In one preferred embodiment, the lift mechanism incorporates a pair of laterally spaced hydraulic lift cylinders. In a further preferred embodiment, the hydraulic lift cylinders are single acting and, in another embodiment, the lift cylinders are double-acting. In the case of single acting lift cylinders (or double acting cylinders operated as a single acting cylinder), hydraulic fluid is admitted to one side of the piston to force the piston towards the opposite end. Springs or the weight of the load system return the piston to the opposite end when the hydraulic pressure is released. In a further preferred embodiment, the hydraulic pressure is applied to both sides of the hydraulic piston head to positively drive it in both directions. This latter embodiment is very useful when it is desired to pack the snow or otherwise handle the snow more efficiently. The double-acting lift cylinder arrangement provides a capability to obtain pressure on the plow when using the appropriate control valve and is desirable for cutting matte or ice build-up and for stacking the snow.
In a further embodiment, instead of a pair of side-mounted hydraulic cylinders, a single acting hydraulic lift cylinder is centrally positioned on the coupler assembly upright members and a projecting arm is actuated in a vertical plane. A chain, coupled to the center of the projecting arm and to the plow support frame operates in a conventional fashion to pivot the frame about the horizontal pivot.
While in the preferred embodiment the plow blade support frame is a "T"-frame as disclosed in the above-referenced Quenzi patent, and the blade is constituted by a pair of centrally hinged plow blades, it will be appreciated that the plow blades may be constituted by a single blade. Moreover, while the blades are positioned using hydraulic cylinders, equivalent electrical or manual blade positioning or angle adjusting mechanism may be employed. In addition, while the "T"-frame of the above-reference Quenzi patent is preferred, an "A"-frame or other frame system may be used as the plow blade support and load transmitting frame.
A further feature of the invention is the provision of a friction mechanism so that the angle between the intermediate support frame and the support frame is maintained when the plow is rested on the ground for disengagement from the truck. In accordance with this feature, a support strap or slide bar is pivotally mounted on one of the plow support frame or intermediate frame and is provided with an elongated slot. The slotted portion of the slide bar is clamped between two pieces of plastic material (UHMW polyethylene or equivalent) with sufficient force to hold the weight of the components when the snow plow is off the truck but not so tight as to prevent lifting of the plow with one or more lift cylinders. This holds the coupler and the power unit and light bar assembly in position relative to the frame when the plow is off the truck and thus provides for easy one- person attachment of the plow to the truck since the projecting ends of the intermediate coupling unit are generally aligned with the truck when the plow blades have been lowered to the ground for storage or disengagement purposes.
DETAILED DESCRIPTION OF THE DRAWINGS
The above and other objects, advantages, and features of the invention will become more apparent when considered with the accompanying specification and following drawings wherein:
FIG. 1 is an exploded perspective view of a snow plow system incorporating the invention,
FIG. 2a is an exploded perspective view showing the vehicle mount attachment being attached to the exemplary frame horns of a truck,
FIG. 2b shows where an electrical socket connector can be mounted,
FIG. 3a is a partially exploded perspective view showing the intermediate attachment frame pivotal attachment of the plow support add load transmissive frame,
FIG. 3b is a partial perspective view showing the latching dogs and the rearwardly projecting latching areas,
FIG. 3c illustrates an alternate latching mechanism,
FIG. 4 is an exploded view showing details of the latch dog operating linkage,
FIG. 5 is an exploded view of the coupler side plate assembly for maintaining the coupler power unit and light bar assembly in position relative to the main frame when the plow is off the truck so as to not require operator intervention to reconnect,
FIG. 6 illustrates the hydraulic system and components thereof,
FIG. 7 is a side elevational view of the assembled unit showing the vehicle approaching for attachment purposes,
FIG. 8 is a side elevation view showing the preferred embodiment of the plow coupled to the vehicle attachment support frame,
FIGS. 9a, 9b 9c illustrations provided to demonstrate the positions of the reactive/reaction forces on the plow and truck with the plow in the raised position (FIG. 9a) when plowing forces are met (FIG. 9b) and when stacking snow the rebound forces are shown in FIG. 9c,
FIG. 10 is an exploded isometric view of a further embodiment of the invention incorporating a conventional single centrally located chain lift cylinder.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a plow blade support frame 10 which, in this embodiment, is the "T"-frame disclosed in the above-referenced Quenzi patent, has a forward end 11 which is provided with a horizontal pivot 12 on which is pivotally mounted a cowling structure 13 carrying a vertical hinge pin 14, which pivotally mounts a pair of blades 15, 16 from the cowling 13. Cowling 13 is provided with a horizontal pivot 17 through which horizontal hinge pin 18 passes and pivotally connects the cowling 13 to the forward end 11 of "T"-frame 10. A pair of angle adjusting hydraulic cylinders 19 and 20 are connected between pivots 20P on the blades 15 and 16 and pivots 21 on the cowling 13 and supplied by hydraulic fluid via hydraulic control valve assembly 22 and hydraulic pump system 23, all as described in detail in the above-referenced Quenzi patent. The hydraulic pump switch assembly HPS has a switch HPS-1 for operating the lift cylinder(s) and left and right blade angle switches HPS-R, HPS-L.
Return springs 24, 25 are coupled between the cowling and each blade, respectively. The blades may be provided with cutting edges 26 and shoe assemblies 27 in a conventional fashion. A bank of trip springs 30 extends from the main horizontal pivot axis 31 (bearing bar 95) through a coupling plate 32 to a turnbuckle 33 which has hook end 35 which is connected to cowling 13. When one or both blades strike, for example, a speed bump in a parking lot, the blade or blades pivot about pivot axis 17 stretching springs 30 and when the obstacle is passed, the blades are returned to their normal position by the bank of trip springs 30. (Only one trip spring 30 is shown in FIG. 1.)
Switch SW-1 is electrically connected to control auxiliary lights LA on light bar assembly 116.
It will be appreciated that up to this point, the assembly as described is essentially fully disclosed in the above-referenced Quenzi patent, which is incorporated herein by reference.
THE PRESENT INVENTION
The preferred embodiment of the present invention includes the vehicle mount attachment frame or push beam assembly 50, the intermediate coupler frame assembly 40, the coupler slide plate assembly 41, coupler latch elements, and coupler latch handle and latch mechanism 42, and the hydraulic lift cylinder means, e.g. the pair of hydraulic lift cylinders 45L and 45R.
THE VEHICLE MOUNT ATTACHMENT (VMA):
The vehicle mount attachments push beam assembly 50 is provided with a pair of spaced latching sockets 51, 52, each of which is formed by a pair of diverging plates 55, 56 and 57, 58 which diverge and form guiding surfaces to account for horizontal misalignment during docking.
The vehicle mount attachment or push beam assembly is best illustrated in FIG. 2a and includes a main cross-beam member 60 having welded thereto socket forming plates 55, 56, 57 and 58, forming latching sockets 51 and 52, respectively, which have outwardly diverging ends 55-O, 56-O, 57-O and 58-O, which provide for some degree of horizontal misalignment as will be discussed more fully hereafter. The ends of beam 60 are provided with welded-on mounting plates 61, 62 which may be bolted to support plates 63, 64, respectively, which, in turn, are bolted or welded to the frame horns 65, 66 on both the passenger and driver side, respectively. In addition, a pair of angle brackets 67, 68 are bolted to the rearward ends of plates 56, 57 as indicated in FIG. 2a. The upper ends of angle brackets 67, 68 are bolted or otherwise welded to the frame horns 65, 66 on the passenger and driver side, respectively.
A latch bar 70 is mounted on the vertical mount attachment and extends transversely between socket-forming plates 55, 56, 57, 58, respectively.
The installation shown in FIG. 2a is in connection with one particular vehicle and it will be appreciated that since the undercarriage structure of various manufacturer's vehicles varies, the installation may vary from vehicle-to-vehicle but, the structure constituted by the vehicle mount attachment frame (VMA) 50 constituted by the latch bar and the socket assemblies described earlier herein is essentially the same for all arrangements.
In FIG. 2b, the driver's side frame horn 66 may be provided with an electrical quick disconnect mounting bracket 71 so that a common electrical cable carrying control signals from switch assembly HPS and power to the electric motor driving hydraulic pump assembly 23 and the lights LA mounted on a light-bar 72 (FIG. 1) can be easily and quickly made.
THE INTERMEDIATE SUPPORT FRAME
The intermediate support frame or coupler assembly 40 and its relation to the "T"-frame is best seen in FIG. 3a. The intermediate support frame is constituted by a pair of spaced steel plates 80, 81, which are joined by a tubular cross-bar frame member 82 and a clevis support cross-bar member 83, the ends of which are welded to respective plates 80, 81. Plates 80, 81 have rearwardly projecting latching arms 84, 85 on the upper surfaces of which are welded reaction bearing surfaces 86, 87. Latch dog housings 88, 89 are positioned above bearing surfaces 86, 87 to form a latching notch LN for receiving latch bar 70 (FIG. 2a). The edges of the rear or aft end of each latch dog housing are bevelled as at 88B and 89B to form camming surfaces for vertical alignment purposes, the ends 84E and 85E of the latching arms are also bevelled to assist in the vertical alignment process. A pair of spaced clevises 90, 91 are welded to frame member 83 and each receive the respective ends of hydraulic lift cylinders 45R and 45L, respectively, as shown in FIG. 1.
The trailing end of "T"-frame 10 is provided with rearwardly projecting parallel arms 92L, 92R, 93L and 93R, which have bearing apertures 94 through which passes the coupler pivot bearing bar 95 having arm 95A which is rotatably mounted in the plates 80, 81 of intermediate support frame 40 by bearing bosses 96 and 97. Horizontal bearing bar 95 passes through each of the bearing apertures 94 in rearwardly projecting arms 92L, 92R, 93L and 93R so as to rotatably mount the "T"-frame for rotation about a horizontal pivot axis and thus support the "T"-frame from the intermediate support frame.
"T"-frame 10 is provided with a cross-bar 98 which is welded on a lower part of the stem 99 of the "T"-frame and has a pair of rearwardly extending brace plates 100, 101 extending to the cross 102 of the "T". A pair of clevises 103, 104 is provided in the lateral ends of cross-bar 98 for receiving the rod ends of hydraulic motors 45R and 45L, respectively (see FIG. 1). The hydraulic cylinders or motors are supplied from a common port on the hydraulic valve assembly 22 and a hydraulic "T"-joint HT (FIG. 1) assures that equal hydraulic pressures are supplied to the two hydraulic motors or cylinders 45R and 45L to thereby pivot the "T"-frame about the horizontal axis constituted by bar 95.
A pair of latching dogs 105, 106 are fixedly secured to bar 95 by set screws 105S and 106S. As shown in FIG. 3b, the latching dogs are housed within latch-dog housings, latch dog 105 being shown within latch dog housing 88.
In the embodiment shown in FIG. 3c, the latch dogs have been replaced by a flexible cable operated pair of spring loaded or biased latch pins, one for each latch bar. Since they are identical, only one will be described. Latch housing 142 is generally "D"-shaped and welded to side plates 80, 81, the lower surface forming a down vertical alignment camming surface 142C which, in conjunction with up vertical alignment camming surface 85E' provides for vertical misalignments to assure seating of latch bar 70 in the latching notch LN'. Latch pins 143 are vertically reciprocated in aligned latch pin holes 144-1, 144-2 and 144-3 (the latter hole being in the bearing surface 85). A stop plate 145 limits the downward travel of latch pin 143 caused by spring 146. An attachment tab 147 is connected to flexible cable 148 which has the opposite end wound on a drum 149 and crank assembly 150, which is mounted between upright plate 110 and 111 but diagrammatically illustrated in FIG. 3c as for convenience of illustration.
As shown in FIG. 4, arm 95A is pivotally connected at its upper end to link 95L. The upper end of link 95L is pivotally connected to latch dog operating arm 95LDA which has a manually actuated handle 95MH. A pair of vertical upright plates 110, 111 are bolted to intermediate support frame side plates 80, 81 and have extending therebetween shelf 112 and back plate 113 which support electric pump and hydraulic assembly 23 and a control valve assembly 22. A change bracket assembly 115 carries lights assemblies 116 and 117. See FIG. 1. A hydraulic pump solenoid may also be mounted on the shelf. FIG. 6 illustrates the hydraulic system, per se.
The lower end of latch operating handle 95MH is pivotally mounted on upright plate 111 and the angular arrangement of the linkages 95LDH and 95L and operating arm 95A are such that when in the latch position for latch dogs 105, 106, the upper pivotal connection of link 95L to the intermediate point on the latch arm 95LDH is over-center to thereby maintain the dog in a latch position at all times. A coupler latch spring plunger 95-SP has an end 95E which enters latch hole 95-LH in vertical upright plate 111.
A cover plate 120C can be used to protect the hydraulic pump and hydraulic valve assembly from the elements.
FIG. 5 illustrates the assembly that is used to maintain the coupler power unit in light bar assembly and position relative to the "T"-frame when the plow is not on the truck so as to thereby maintain the rearwardly projecting arms in a position so that the unit can be quickly attached to a truck and not require operator intervention. In this arrangement, the horizontal pivot arrangement between the "T"-frame and the intermediate support frame or coupler assembly is provided with a coupler slide plate assembly 41 which includes a slide plate or bar 120 having a lower end pivotally supported on a pivot boss 121 on the end of the "T"-frame 10. A slot 122 is formed in plate 120. A pair of plastic washers (UHMW polyethylene or equivalent) is clamped to the inside and outside surfaces of the slide bar 120 by a threaded lug or stud 123 on upright plate assembly 110 (see FIG. 1). Hex nut 124 and a Belville washer 125 are tightened with sufficient force to hold the weight of the components when the plow is off the truck but, not so tight as to prevent lifting of the plow with the lift cylinders 45R, 45L. The clamping force is adjusted by means of the hex nut and Belville washer and holds the power unit and light bar assembly in position relative to the "T"-frame 10 when the plow is off of the truck.
FIG. 7 shows the plow aligned for quick coupling with the latch handle forward and the latch dogs 105, 106 up, so that the latching notch LN is open to receive horizontal latch bar 70. In FIG. 7, when the truck is driven slowly forward, any horizontal misalignment is corrected by the guide surfaces 55-O . . . 58-O (FIG. 2a) and any vertical misalignments will be corrected by camming surfaces 88B, 89B (too high) on the latch dog housing or the surfaces 84E, 85E (too low) on the latching arms 84 and 85, respectively. When the latch bar is seated in the pair of latch notches LN under each latch dog housing, a latching linkage is operated to rotate the dogs into locking position with the downward leg of each latch dog behind or aft of the latch bar 70. Spring pin 95E is biased into hole 95LH on plate 111 to positively lock the linkage in the position shown in FIG. 8.
Referring now to FIGS. 9a, 9b and 9c, are illustrations which demonstrate the positions of the reactive/reaction forces on the plow and truck. In FIGS. 9a, 9b and 9c, while the plow and "T"-frame and the intermediate coupling assembly are shown spaced from the truck frame mounting assembly, it will be appreciated that these views are shown just for purposes of illustration in that the forces occur only when the plow is mounted on a truck, namely, when the rearwardly projecting arms 84, 85 are engaged in sockets 51, 52. In FIG. 9a, when the plow is raised, as when the truck is moving from one location to another or stacking snow, the reaction forces on the intermediate frame member 40 are the two reaction forces F1, F2 and their equal opposite reaction forces are F3, F4, respectively. In conjunction with the two rearwardly projecting arms, the reaction forces on plates 86, 87 (the forces acting in the direction F2) are equal and opposite to the reaction forces on cross-beam 60 on the push-beam assembly 50. The equal and opposite reaction forces on the lower end of dog housings 88, 89 and the latching surfaces on latch dog 105, 106, e.g., the forces F1, and the equal and opposite reaction forces on latch bar 70 provided a very stable two point hitch assembly and, at the same time, provided for quick easy attachment with significant horizontal alignment features provided by the diverging outer plates 550, 560, 570 and 580 and vertical alignments caused by camming surfaces 84E, 85E and 88E and 89E with bearing bar 70. When plowing snow (FIG. 9b) the force applied by the cutting edge 26 and snow in the plow blades, per se, whether the plow blade is being pulled or pushed is delivered essentially to the latch bar 70 with the equal and opposite reaction forces F5, F6, F7, F8 being illustrated in FIG. 4b. When stacking snow as when force is applied on the cutting edge 26 in the direction indicated by the force FP', an equal and opposite reaction force will be applied between the latch dog and latch dog housing F9 and the latch bar F10 and the forward-most end of the push-beam assembly 50 and its guide plates 560 and 570 will have the reaction force F11 which is equal and opposite to the reaction force F12 on the intermediate frame member 40.
CENTRALLY LOCATED LIFT CYLINDER EMBODIMENT
As shown in FIG. 10, a single centrally located chain lift cylinder may be used to lift the "T"-frame for transport and other purposes. In this embodiment a further cross-bar 130 is weld mounted between vertical uprights 110 and 111 and carries a central clevis 131 for pivotally supporting the lower end of centrally positioned hydraulic cylinder or motor 132. The light assembly cross-bar 133 also has a centrally located clevis 134 for pivotally receiving the end of lift arm 135. The outer end of lift arm 135 pivotally receives the upper or piston arm end 138 of hydraulic cylinder 132 at pivot 136. A chain 138 is hooked on the outermost end of left arm 135 and is coupled to the "T"-frame support frame 10' and operates in essentially the same fashion as disclosed in the aforementioned Quenzi patent.
While preferred embodiments of the invention have been shown and described, it will be appreciated that numerous modifications and adaptations will be readily apparent to those skilled in the art and embraced by the claims appended hereto. | A quick hitch-unhitch attachment for mounting a snow working implement on a vehicle, comprising a vehicle mount attachment (VMA) frame secured to the vehicle, has a pair of spaced sockets which are positioned below and behind the vehicle bumper when mounted on the vehicle. A first pair of reaction bearing surfaces are aligned with and to the rear of the spaced sockets and a transverse latch bar means extends transversely of the sockets. An intermediate support frame has a rearward end with a pair of latching arms extending in a rearward direction and in general alignment with the sockets, respectively. Each latching arm has a further reaction bearing surface for bearing against respective ones of the first pair of reaction bearing surfaces. A support frame has a forward end attached to the snow working implement and a rearward end pivotally connected to the intermediate frame for rotation about a horizontal axis. A latching mechanism on the intermediate support frame for positioning a latch member rearwardly of the transverse latch bar. A lift mechanism on the intermediate support frame pivots the support frame about the horizontal axis and lifts the support frame and working implement off the ground such that the weight thereof is borne by the reaction bearing surfaces and the pair of spaced socket means. A friction slide plate maintains the angular relationship between the intermediate frame and the support frame when the intermediate support frame is not coupled to the VMA frame. | 4 |
This application is a continuation of application Ser. No. 08/506,965, filed Jul. 28, 1995, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an AC type plasma display apparatus.
2. Description of the Related Art
Recent years, a plasma display panel such as an AC type plasma display apparatus is excepted to be a large thin color display apparatus.
FIG. 1 shows an example of a surface discharge AC type plasma display panel. This plasma display panel comprises a front side substrate 1 having column electrodes 2 and 2 and a back side substrate 5 having row electrodes 6. A plurality of pairs of the electrodes 2 and 2 as sustaining electrodes are formed in parallel on the glass substrate 1 of a display side. A dielectric layer 3 and a MgO layer 4 is formed in turn on the electrodes 2 and 2. Moreover, the row electrodes 6 are formed on the back side glass substrate 5 as address electrodes. A fluorescent layer 7 is formed on the row electrodes 6. The plasma display panel is constructed in such a manner that the front side substrate 1 and the back side substrate 5 are assembled and sealed with a gap so that the row electrodes 6 are disposed perpendicular to the sustaining electrodes 2 to define a discharge region 8 in the gap. After exhausting the discharge region 8, a rare gas is introduced and sealed into the discharge region 8. In this way, a pixel of a unit cell is formed at each intersection between each electrode 2 of the substrate 1 and each electrode 6 of the substrate 5. The plasma display panel is capable of displaying an image by a plurality of the pixels driven by a driving circuit.
In case of the displaying of the above plasma display panel, a discharge-starting voltage or higher voltage is applied across the electrodes 2 and 6 to the introduced and sealed rare gas in the selected pixel, so that a discharge occurs on the MgO layer 4 to emit light. This discharge-starting voltage is selected on the basis of the gap distance between the substrates 1 and 5, the kinds of introduced and sealed inert gas and the pressure thereof and the properties of the dielectric layer 3 and the MgO layer 4. The charges of anions and electrons transfer to the internal wall of the pixel in the opposite polarization directions to each other during the application of the discharge-starting voltage so as to charge the internal wall in a manner that the MgO layer 4 is divided into two opposite polarization regions. The wall charges remain on the MgO layer 4 because of a high resistance value thereof without decrement. This discharge is stopped immediately after emitting light by these wall charges because the electric field is weakened due to the formation of the electric field of the inverse polarization in the pixel.
The discharge is intermittently maintained by the application of the discharge sustaining voltage across the electrodes 2 and 2 in which the discharge sustaining voltage is an AC driving voltage and lower than a discharge-starting voltage because of the wall charge. This is referred to as a memory function of the plasma display panel. The selection of the dielectric layer 3 is important for the determination of the AC driving voltage in the pixel.
It is well known to use lead oxide (PbO) for the dielectric layer 3.
In such a plasma display panel, the discharge at the starting of discharge is stopped immediately after emitting light because of the charge transfer in the pixel. Since a dielectric layer 3 of PbO has a large dielectric constant of 9 to 12, the amount of discharge current flowing in the pixel is large per one emission of light and therefore the consumed electric power of the plasma display panel is also large.
Therefore, it has been attempted to make the dielectric layer 3 of SiO 2 with a low dielectric constant in order to reduce the pixel's capacity. A problem with such a method is that it is difficult to form the SiO 2 films of 20 to 30 microns thick since the SiO 2 layer is formed by a vacuum method or sputtering method. Another problem is that there is also an occurrence of cracks in a thick SiO 2 layer.
SUMMARY OF THE INVENTION
In view of the problems, an object of the present invention is to provide an AC type plasma display apparatus which reduces the consumed electric power thereof.
An AC type plasma display apparatus according to the present invention comprises:
a plurality of column electrodes disposed in parallel to each other;
a plurality of row electrodes spaced from and disposed perpendicular to said column electrodes;
a dielectric layer covering said column electrodes and charging a wall charge wherein said dielectric layer is made of a low melting point glass having a dielectric constant of 8 or less.
The AC type plasma display apparatus according to the present invention achieves the above object, since the dielectric layer has a dielectric constant of 8 or less. That is, the pixel's capacity in the intersection between the column electrode and the row electrode becomes small. Therefore, the consumed electric power per one discharge is reduced by the decrease of the amount of discharge current flowing in the emitting plasma display panel.
The above and other objects, features and advantages of the invention will become apparent from the following detailed description which is to be read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially enlarged cross-sectional view showing a conventional AC type plasma display panel;
FIG. 2 is a partially enlarged cross-sectional view showing an AC type plasma display panel according to the present invention; and
FIG. 3 is a graph showing a result from the comparison in the amount of discharge current per one pixel both of an AC type plasma display panel according to the present invention and a conventional plasma display panel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of a plasma display panel according to the present invention will be described hereinbelow with reference to FIGS. 2 and 3.
FIG. 2 is a cross-sectional view showing one of a plurality of pixels which form a surface discharge AC type plasma display panel employing a three-electrode structure. This pixel includes a front side transparent substrate 11 of glass as a display surface; and a back side glass substrate 12 disposed in parallel to the front side substrate 11 at a gap space of 100 to 200 microns. For maintaining the gap, barrier ribs (not shown) are formed between the front side substrate 11 and the back side substrate 12. The front side substrate 11, the back side substrate 12 and a pair of the barrier ribs define and surround a space as a discharge region 13.
The front side substrate 11 has a plurality of pairs of transparent electrodes 14 and 14 as column electrodes on its surface facing the back side substrate 12 in such a manner that the column electrodes extend in parallel to each other. The pair of column electrodes serve as control electrodes for driving the pixel and are formed of a transparent conductive material, such as indium tin oxide (ITO), tin oxide (SnO 2 ) or the like with a thickness of about several hundreds nm order by using a vacuum deposition method. For improving the conductance of the whole electrodes, metal auxiliary electrodes 15 are formed on and along the far opposite edges of the transparent electrodes 14 and 14 respectively to the adjacent edges thereof. The metal auxiliary electrodes 15 are made of Aluminum (Al) and each has a width narrower than that of the column electrode 14. An electrode protective layer 16 is formed on the pair of column electrodes 14 and 14 and the metal auxiliary electrodes as covering them at a thickness of 0.1 to 0.2 microns. A dielectric layer 17 is formed on the protective layer 16 at a thickness of 20 to 50 microns. A protective layer 18 made of SiO 2 is formed on the dielectric layer 17 at a thickness of about several hundreds nm order. A MgO layer 19 made of magnesium oxide (MgO) is formed on the protective layer 18 at a thickness of about several hundreds nm order.
The dielectric layer 17 is made of a low melting point glass having a softening point of 650° C. or less and a dielectric constant of 8 or less. The dielectric layer 17 of the low melting point glass contains sodium oxide (Na 2 O) and boron oxide (B 2 O 3 ) as components. Some examples of the low melting point glass are shown in the following table 1 in which low melting point glasses denoted by glass-codes (Product Numbers) are commercially available from Nihonn Denki Garasu kabusiki kaisya.
TABLE 1______________________________________ Softening DielectricGlass-code Components point (°C.) constant______________________________________GA-4 Na.sub.2 O--B.sub.2 O.sub.3 --SiO.sub.2 625 6.2GA-12 Na.sub.2 O--B.sub.2 O.sub.3 --ZnO 560 6.7LS-0500 Na.sub.2 O--B.sub.2 O.sub.3 --SiO.sub.2 585 7.6______________________________________
The electrode protective layer 16 is made of an inorganic material different from that of the dielectric layer 17, such as a glass containing lead oxide (PbO) and/or silicon dioxide (SiO 2 ), to protect the electrodes 14. The electrode protective layer 16 is formed in order to prevent from the internal dispersion of sodium (Na) from the dielectric layer 17 to the electrodes 14 and 15. This is because an alkali glass of the dielectric layer 17 with a low melting point contains sodium (Na) which causes a corrosion of the electrodes 14 and 15. It is noted that the protective layer 18 may be omitted.
On the other hand, the back side substrate 12 has a plurality of addressing electrodes 21 as row electrodes on its surface facing the front side substrate 11 in such a manner that the row electrodes extend in parallel to each other. The row electrodes also serve as sustaining electrodes for driving the pixel and are formed of a high reflectance metal such as Al and Al alloy at a thickness of about 1 microns by using a vacuum deposition method. The row electrodes 21 made of a high reflectance metal such as Al and Al alloy have a reflectance of 80% or more in a wavelength band of 380 to 650 nm. It is noted that the row electrodes 21 may be made of not only Al and Al alloy, but also an appropriate metal or alloy thereof having a higher reflectance such as Cu, Au and an alloy thereof.
The barrier ribs (not shown) are formed between the row electrodes 21 on the back side substrate 12 to define and surround spaces as discharge regions.
The row electrodes 21 and the exposed surface of the back side substrate 12 are covered with a fluorescent layer 22 for a monochrome plasma display panel. In case of a color plasma display panel, three fluorescent layers made of fluorescent substances for emitting red (R), green (G) and blue (B) lights are formed in turn on the corresponding row electrodes 21 respectively, so that each pixel emits light correspondingly to the fluorescent substance.
The back side substrate 12 and the front side substrate 11 are assembled in such a manner that the row electrodes 21 are perpendicular to the column electrodes 14. After assembled, the intersections with a gap between the column electrodes 14 and 14 and the row electrodes 21 define discharge regions 13 for the emitting regions of pixels. The front side substrate 11 and the back side substrate 12 are fixed to each other and the gap of the discharge regions 13 is exhausted by a vacuum pump. After that, the assembly is baked so that the surface of the MgO layer 19 is activated. Next, an inert mixture gas including a rare gas of xenon (Xe) at 1 to 10% is introduced and sealed into the discharge regions 13 at a pressure of 200 to 600 Torr.
In the conditions that the plasma display panel is driven, a pulse voltage for controlling the starting of the emission of light, and of sustaining the emission and of stopping the emission of light is supplied to the column electrodes 14 and 14. A data pulse for an image to be displayed including data starting the emission of light and sustaining the emission and stopping the emission is supplied to the row electrode 21.
An operation of the plasma display panel will be described. The embodiment (A) according to the present invention of FIG. 2 is compared to a comparative embodiment comprising a dielectric layer of PbO with the structure shown in FIG. 1.
The following table 2 shows components and dielectric constants of the dielectric layers 17 and 5 in the embodiment (A) and the comparative embodiment. In the table 2, low melting point glasses denoted by glass-codes (Product Numbers) are commercially available from Nihonn Denki Garasu kabusiki kaisya.
TABLE 2______________________________________ Dielectric Glass-code Components constant______________________________________Embodiment(A) GA-12 Na.sub.2 O--B.sub.2 O.sub.3 --ZnO 6.7Comparative PLS3232 PbO--B.sub.2 O.sub.3 --SiO.sub.2 10______________________________________
Each thickness of the dielectric layers 17 and 5 of the embodiment (A) and comparative are 30 micron meters. Both the display panels are formed in the same manner excepting the materials of the dielectric layers 17 and 5 and the electrode protective layer 16.
Next, amount of discharge current flowing in the emitting plasma display panel of the present invention is compared with that of the comparative embodiment. FIG. 3 shows curves of variations of discharge currents flowing in the emitting pixels of both the plasma display panels as a function of time under the conditions that a sustaining voltage 170 V is applied across the column electrodes to discharge pixels once. In FIG. 3, curve a represents the variation of the embodiment A and curve b shows that of the comparative embodiment.
As seen from FIG. 3, the amount of discharge current of the embodiment A and comparative embodiment reach peak values at substantially the same time respectively, during the application of the sustaining voltage. However, the peak of the embodiment A is about 1/2 of the peak of the comparative embodiment. The flows of discharge current of the embodiment A and comparative embodiment are terminated at substantially the same time respectively. The reason for this is as follows: The capacity C of the pixel is represented by the following equation:
C=ε·ε.sub.0 (S/D)
wherein ε denotes a dielectric constant, ε 0 denotes the permittivity in vacuum, S denotes an area of the electrode and D denotes a gap distance between the electrodes. Namely, the pixel's capacity C is in proportion to the dielectric constant ε of the dielectric layer and thus, as decreasing the dielectric constant ε of the dielectric layer, the pixel's capacity C decreases. Therefore, the capacity of pixel of the embodiment A is smaller than that of the comparative embodiment because of the above equation under the conditions that the dielectric constant ε of the dielectric layer 17 in the embodiment A is 6.7 and that of comparative embodiment is 10. As a result, the amount of discharge current flowing in the emitting plasma display panel of the present invention is less than that of the comparative embodiment under the application of the same voltage across the electrodes.
The reduction of permittivity in the layer covering the electrode makes the consumed electric power in the embodiment A decrease rather than that of the comparative embodiment, since the amount of discharge current flowing in the emitting plasma display panel of embodiment A is smaller than that of the comparative embodiment.
In addition, the dielectric layer 17 is preferably formed with a thickness in the range of 20 to 50 microns. This is because a destruction of insulation may occur when the dielectric layer 17 is formed with a thickness less than 20 microns so as to reduce the durability against the applied voltage across the electrodes 14 and 14. When the dielectric layer 17 is formed with a thickness of 30 microns, its durability against the applied voltage is about 1 kV. Furthermore, when the dielectric layer 17 is formed with a thickness 50 microns or more, the discharge-starting voltage becomes 400 V or more so as to make a difficulty of controlling the driving circuit for the plasma display panel. Therefore, the preferred thickness range of the dielectric layer 17 is within 20 microns or more and 50 microns or less.
In this way, the above embodiment is described as a surface discharge AC type plasma display panel which comprises the front side substrate having the column electrodes and the back side substrate having the row electrodes. In addition to this embodiments, not restrictive, the present invention may be applied to an opposite AC type plasma display panel in which the column and row electrodes are formed with a space in one substrate, and furthermore to all of AC type plasma display panels in which the electrodes for discharge are covered with dielectric layers.
According to the present invention, the AC type plasma display apparatus comprises a dielectric layer made of a low melting point glass having a dielectric constant of 8 or less, so that the pixel's capacity in the intersection between the column electrode and the row electrode become small. As a result, the consumed electric power per one discharge is reduced by the decrease of the amount of discharge current flowing in the emitting plasma display panel. | An AC plasma display includes a plurality of parallel column electrodes (14); a plurality of parallel row electrodes (21) disposed from, and perpendicular to, the column electrodes (14); a dielectric layer (17) for forming a wall charge is made of a low dielectric constant glass having a low melting point includes sodium oxide and boron oxide and covers the column electrodes (14); and an electrode protective layer (16) made from an inorganic material, for example silicon dioxide, prevents diffusion of sodium from the dielectric layer (17) to the column electrode (14). The dielectric layer (17) is made of a glass having a low dielectric constant of 8 or less to reduce pixel capacitance thereby reducing the electrical power consumption of the display. | 7 |
FIELD OF THE INVENTION
The present invention relates generally to power converters and, more particularly, to a power converter having an integrated AC/DC and DC/DC converter capable of starting an AC machine from either a DC or AC input source.
BACKGROUND OF THE INVENTION
There are various applications in which it is desirable to have the capability of starting an AC machine using either an AC or DC input source. For example, in aerospace applications a three phase AC source and a DC source are typically available. The ability to start an engine using either one of these sources provides enhanced system reliability.
A variety of power converter designs that afford start capability from AC or DC inputs are in existence. These conventional start converters utilize separate front end start converters, one for AC start (AC/DC converter) and the other for DC start (DC/DC converter). An example of such a start converter is shown in FIG. 1. Start converter 10 includes an AC/DC converter 12 that converts a three phase AC input to DC when switches S1 are closed. Three phase transformer 22 steps up the three phase AC voltage, rectifier bridge 24 rectifies the transformer voltage output, and the rectified output is supplied to a three phase DC/AC inverter 16, the output of which drives AC machine 17. The AC machine may be a synchronous, induction or permanent magnet machine. By pulse width modulation control of inverter 16, variable frequency and voltage can be provided to AC machine 17.
DC activation of machine 17 by DC battery 15 is by selectively switching on transistors 13 of DC/DC converter 14, producing multi-phase AC, which is stepped up in voltage by multi-phase transformer 28, and then rectified by rectifier stage 19. DC/AC inverter 16 then converts the rectified output to AC to drive AC machine 17. During DC activation, the AC inputs are off with switches S1 open.
Power converters utilizing separate front end start converters, such as the converter 10 just described, exhibit increased weight and decreased reliability. Accordingly, there exists a need for a power converter that is devoid of such drawbacks.
SUMMARY OF THE INVENTION
The present invention is directed to a power converter having integrated AC/DC and DC/DC converters that share common transformer magnetics and a common output rectifier.
In an illustrative embodiment of the invention, a power converter for starting an AC machine comprises at least one transformer for stepping-up AC source voltages, at least one rectifier for rectifying output voltages from the at least one transformer, a three phase inverter for inverting rectified voltages from the at least one rectifier for providing three phase voltages for starting the AC machine, and a DC to AC converter for converting DC source voltage to AC inverted voltages. The three phase voltages for starting the AC machine are derived from one of the AC and DC source voltages through the at least one transformer and the at least one rectifier.
Preferably, the at least one transformer has a set of first primary windings connected in wye for receiving the AC source voltages and a set of second primary windings connected in wye for receiving the inverted voltages of the DC source voltage. In addition, half of the transformer secondary windings may be connected in wye and the other half of the secondary windings may be connected in delta. This topology results in low harmonic generation.
Advantageously, with a common rectifier to rectify the transformer output voltages, and with the same transformer magnetics being utilized for both the AC/DC and DC/DC operating modes, power converters in accordance with the present invention have integrated AC/DC and DC/DC converter portions. This integration serves to minimize the total components, allowing the converter to be both compact and lightweight--two critical attributes for aerospace applications.
BRIEF DESCRIPTION OF THE FIGURES
For a better understanding of the present invention, reference is had to exemplary embodiments thereof, considered in conjunction with the accompanying figures in which like reference numerals designate like elements or features, wherein:
FIG. 1 schematically illustrates a prior art start converter;
FIG. 2A is a schematic diagram of a first embodiment of the present invention particularly suitable for high power applications;
FIGS. 2B-2D are schematic diagrams further illustrating the first embodiment of FIG. 2A;
FIG. 3A is a schematic diagram of a second embodiment of the invention, particularly useful for low power applications; and
FIG. 3B schematically illustrates transformer winding connections of the second embodiment; and
FIG. 4 schematically illustrates a third embodiment of the invention, useful for low power applications.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 2A, there is shown a power converter 30, which is a first embodiment of the present invention. Converter 30 is particularly useful for high power applications, e.g., output power between 5 kW and 30 kW.
In a first mode of operation, AC machine 17 is started by using three phase AC input voltage from sources A, B, C. This AC input voltage is stepped up by transformers T1 and T1'. The transformer outputs are rectified to provide DC voltage and then inverted to produce AC with variable frequency and voltage to start AC machine 17. In a second mode of operation, AC machine 17 is started from power originating from DC battery 32. Converter 30 converts the DC input voltage of battery 32 to three phase AC by means of inverter 31. This three phase AC is then stepped up, rectified and inverted again to produce variable frequency, variable voltage AC to start AC machine 17. Advantageously, both operating modes utilize common magnetics of transformers T1 and T1' and a common rectifier bridge 37 to rectify the stepped up voltages. Advantages of this circuit topology include reduced complexity and weight in comparison to prior art designs.
Three phase transformer T1 is comprised of six primary windings P1 to P6 and three secondary windings S1 to S3. (The term "primary winding", when used herein, refers to a winding, disposed on a transformer core, that receives an AC input voltage. The term "secondary winding", when used herein, refers to a winding that provides a transformed output voltage induced by application of an input voltage to an associated primary winding. The side of the transformer core in which the windings are shown herein does not dictate whether a particular winding is a primary or secondary winding).
AC voltage applied to winding P1 or P2 induces voltage in winding S1, voltage in windings P3 or P4 induces voltage in winding S2 and voltage in windings P5 or P6 induce voltage in winding S3. Transformer T1' can be of identical construction to transformer T1, with windings P1' to P6' and S1' to S3' being the same as corresponding windings P1 to P6 and S1 to S3.
The windings of transformer T1 are preferably connected in a wye-wye configuration, while the windings of transformer T1' are preferably connected in a wye-delta configuration, as shown in FIG. 2A, and also shown schematically in FIG. 2B. Winding trios P1, P3, P5; P2, P4, P6; P1', P3', P5'; P2', P4', P6'; and, S1, S2, S3 are connected in wye whereas windings S1', S2' and S3' are connected in delta. This arrangement results in low harmonic power generation and a high power factor.
Consequently, a harmonic filter is typically not needed with the preferred topology. (It is noted that each of magnetic cores M1 and M1' of FIG. 2B may comprise a single three-phase core or three separate cores as CR1, CR2, CR3).
Detailed operation of the two operating modes are as follows. In the first mode, i.e., AC/DC/AC, transistors Q1 to Q12 of inverter 31 are OFF, thereby preventing the DC battery 32 voltage from being applied to the transformer windings. For the start operation, each of switches S are closed via appropriate control means (not shown) to enable the three phase AC voltage V A1 (=V<0°), V B1 (=V<120°) and V C1 (=V<-120°) to be applied to the respective primary windings of transformers T1 and T1'. FIG. 2C further illustrates the first mode. Inverter 31 is omitted for clarity. AC current flows through primary windings P1, P3, P5, and P1', P3' and P5', and no current flows through the other primary windings. By way of example, voltages V A1 , V B1 and V C1 may be on the order of 115 V at 400 Hz, and the windings on transformers T1 and T1' can be designed to either step up or step down the three phase voltage. The respective transformed (e.g., stepped up) three phase voltage is designated as voltages V A1T , V B1T , and V C1T in the first operating mode. These voltages are applied to nodes N1-N3 and N1'-N3' of respective rectifier bridges 37a and 37b (which together comprise common rectifier 37). The rectified outputs are filtered by capacitor C L to produce DC link voltage, which is provided to three phase inverter 16. Inverter 16 converts the rectified waveform back to AC as the transistors are periodically switched on and off by an appropriate control means (not shown). By pulse width modulation control, a variable speed and amplitude three phase output voltage can be produced. The inverter output voltages are used to start AC machine 17.
Referring now to FIG. 2D, which illustrates the second mode, utilizing the DC input portion of converter 30, the AC machine 17 is started with power originating from DC battery 32. In this mode, the switches S are all opened. The voltage of battery 32, e.g., 24 or 48 V, is applied to both of three phase inverters 31a and 31b, which are connected in parallel and which together comprise input inverter 31. Voltage supplied to inverter 31a is filtered by capacitor C1 connected across circuit nodes 34 and 36; voltage to inverter 31b is filtered by capacitor C2 connected across circuit nodes 44 and 46, with nodes 36 and 46 being connected via lead 47 and nodes 34 and 44 being connected via lead 43. Transistors Q1-Q6 are periodically switched on and off in a conventional manner via a suitable three phase controller (not shown) to produce three phase AC voltage. This three phase voltage at nodes n4, n5 and n6 is designated as voltages V A2 , V B2 and V C2 , respectively (and differ in phase from one another by 120° at the three nodes). Transistors Q7 to Q12 are also periodically switched on and off to produce essentially the same three phase voltage at nodes n7, n8 and n9, with the voltage phases at nodes n7, n8 and n9 being the same as the phases at nodes n4, n5 and n6, respectively.
The three phase voltage at nodes n1, n2 and n3 produce AC in windings P2, P4, and P6, thereby inducing voltage in secondary windings S1, S2 and S3. This produces transformer output voltages V A2T , V B2T and V C2T at nodes N1, N2 and N3, respectively, which voltages correspond in phase to the respective input voltages V A2 , V B2 and V C2 . The turns ratio between these primary and secondary windings are preferably designed to provide the same voltage amplitude as in the AC/DC conversion case (mode 1 discussed above). Likewise, the time varying voltages at nodes n7, n8 and n9 drive currents in windings L2', L4' and L6' thereby inducing corresponding voltage in coils S1', S2' and S3'. As a result, output voltages V A2 , V B2 and V C2 of preferably the same amplitude are provided at respective nodes N1', N2' and N3'. Rectifiers 37a, 37b then operate in the same manner as in the first mode discussed above to rectify and invert the transformer output voltages. The rectified voltages are filtered by capacitor C L to provide DC link voltage which is inverted by inverter 16 to produce three phase AC to start AC machine 17.
As mentioned above, instead of employing three separate magnetic cores for each of transformers T1 and T1', a three-phase transformer having a single magnetic core could be used for each of the two transformers. Thus, cores CR1, CR2 and CR3 (as well as cores CR1', CR2' and CR3'), could be replaced by a single magnetic core having three legs, with coils P1, P2, S1 wrapped around one of the three legs, coils P3, P4, S2 wrapped around another leg, and so forth. The use of a single three-phase transformer permits a savings of core material. It is noted that a further savings of core material can be attained by using a single magnetic core for the entire transformer T. However, this would be impractical for high power applications in which a large voltage boost occurs, e.g., 24/48 V originating from the DC battery being stepped up to 250-300 V on the output. High currents accompany the large step up in voltage--consequently, the use of at least two magnetic cores is preferred for this application.
Referring now to FIG. 3A, a second embodiment of the present invention is shown, designated as power converter 50. This embodiment is particularly suitable for low power applications, e.g., less than 5 kW of output power. As in the high power embodiment of FIGS. 2, power converter 50 employs common transformer magnetics and a common rectifier, 57, for the AC/DC and DC/DC conversion circuitry.
Power converter 50 differs in topology from power converter 30 discussed above primarily via the utilization of a single three phase input inverter 31c and a twelve winding transformer T10. As is apparent from FIG. 3A, and which is shown schematically in FIG. 3B, primary windings P11, P12, P13 and P14, P15, P16 are connected in wye. Secondary windings S10, S12, S14 are also connected in wye, whereas secondary windings S11, S13, S15 are connected in delta. This topology is preferable to minimize harmonic pollution of the AC sources A, B and C. Also, single phase magnetic cores CR10, CR20 and CR30 are used for windings P11, S10, S11, S14; P12, S12, S13, P15; and P13, S14, S15, P16, respectively. These three cores can alternatively be replaced with a single, three phase magnetic core.
In a first mode of operation, i.e., AC/DC/AC power conversion, three phase AC energy from AC voltage sources A, B, C are applied to transformer T10 by dosing each switch S and switching each of transistors 61 of inverter 31c OFF. Hence, AC voltages V A1 , V B1 and V C1 are applied to respective primary windings P11, P12, P13. Consequently, current flows through primary winding P11, inducing voltage in secondary windings S10 and S11. Likewise, current flow through winding P12 induces voltage in secondary windings S12, S13; current flow through winding P13 induces voltage in secondary windings S14 and S15. As a result, transformer output voltages V A1T , V B1T and V C1T are produced and applied to circuit nodes G1, G2 and G3, respectively and to nodes G1', G2' and G3', respectively, of common rectifier 57. These voltages are stepped up versions of the respective AC input voltages V A1 , V B1 and V C1 .
The rectified voltages from the upper and lower rectifier bridge portions of rectifier 57 are filtered by link capacitor C K to provide DC link voltage. Output inverter 58 converts the rectified output back to AC to drive AC machine 67.
In the second operating mode of power converter 50, the switches S are opened and the transistors 61 of input inverter 31c are alternately switched on and off by a three phase controller. This converts DC voltage, e.g., 24/48 V from battery 51 (which voltage is applied to inverter 31c via capacitor C5) to three phase AC voltage, namely, voltages V A2 , V B2 and V C2 . These voltages are applied to respective primary windings P14; P15; and P16, thus driving current flow through secondary winding pairs S10, S11; S12, S13; and S14; S15, respectively. As a result, three phase transformer output voltages consisting of voltages V A2T , V B2T and V C2T are produced and applied to nodes G1, G2, G3, respectively, and to nodes G1', G2', G3', respectively. These output voltages are preferably of the same amplitude as voltages V A1T , V B2T , V C2T of the first operating mode. Rectifier 57 and inverter 58 then operate in the same manner as the first mode to start AC machine 67.
With reference now to FIG. 4, a third embodiment of the present invention, power converter 70, is particularly suitable for low battery voltage (e.g., 24 V) applications. This embodiment utilizes a transformer T11 having three primary windings P21-P23 used in a first operating mode (AC/DC/AC), six primary windings P24-P29 used in a second operating mode (DC/AC/DC/AC) and six secondary windings S21-S26 which provide three phase output voltage in either operating mode. Windings P21-P23 and S21, S23 and S25 are connected in wye; windings S22, S24, S26 are connected in delta; and winding pairs (P24, P25); (P26, P27); (P28, P29) are connected in push pull configuration as shown. Three single phase cores CR21-CR23 are employed; however, it is understood that a single three phase transformer could alternatively be utilized.
In the first operating mode, the switches S are closed and each transistor 74 of inverter 72 is switched OFF by a suitable control means. Voltages V A1 , V B1 and V C1 (e.g., 115 V RMS) are thus applied to respective windings P21-23, exciting secondary windings S21-S26 to produce corresponding transformer output voltages V A1T , V B1T and V C1T . In the second operating mode, the DC voltage of battery 71, e.g., 24 V, which is applied to transistors 74 via capacitors C6-C8, is converted to three phase AC by appropriate switching of transistors 74 via a control means. This three phase AC consists of voltages V A2 across windings P24, P25; V B2 across windings P26, P27, and V C2 across windings P28, P29. The transformer steps up the voltage waveforms, thus producing transformer output voltages V A2T , V B2T and V C2T (e.g., 200-300 V RMS). In both operating modes, rectifier 57 rectifies the respective transformer output voltages, and the rectified output is filtered by DC link capacitor CK to provide DC link voltage. This voltage is inverted to AC by output inventer 58, thereby starting AC machine 79.
For the low power applications mentioned above, the second embodiment of FIG. 3A is preferable when higher DC battery voltages are used, e.g., 48 V. On the other hand, the third embodiment of FIG. 4 is preferable for lower DC battery voltages, e.g., 24 V. The reason for this is that in the second embodiment, there are two transistors of the input inverter active at a time, while in the third embodiment, only one transistor of the input inverter is active at a time. As a result, there would be higher losses in the second embodiment if a lower DC voltage is used.
For any of the three embodiments of FIGS. 2-4, there may be applications where it is desirable to use only the DC output of the rectifier, rather than the AC output of the output inverters. Hence, for these applications, the output inverter would be omitted.
In addition, while the embodiments of the present invention disclosed above utilize three phase AC, the present invention may also be useful for other polyphase AC, e.g., six phase.
It will be understood that the embodiments described herein are merely exemplary and that one skilled in the art can make many modifications and variations to the disclosed embodiments without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention as defined by the appended claims. | In an illustrative embodiment, a power converter for starting an AC machine comprises at least one transformer for stepping-up AC source voltages, at least one rectifier for rectifying output voltages from the at least one transformer, a three phase inverter for inverting rectified voltages from the at least one rectifier for providing three phase voltages for starting the AC machine, and a DC to AC converter for converting DC source voltage to AC inverted voltages. The three phase voltages for starting the AC machine are derived from one of the AC and DC source voltages through the at least one transformer and the at least one rectifier. | 7 |
This is a division of U.S. patent application Ser. No. 493,145, filed July 30, 1974 now U.S. Pat. No. 3,998,811 granted Dec. 21, 1976 which, in turn, is a continuation-in-part of U.S. patent application Ser. No. 234,645, filed Mar. 14, 1972, now abandoned.
BACKGROUND OF THE INVENTION
Compounds similar to those of formula ##STR3## but solely in the form of racemates have been disclosed in J. Org. Chem. 27 3781 and 3788 (1963), Reeder et al., U.S. Pat. No. 3,371,085, and Japanese Patent 44/26302. These racemates are known to have sedative and tranquilizing effects.
However, the receptor theory of drug action, which teaches that pharmacologically active compounds act by interaction with a receptor which is a part of the cell affected by the action of a drug and is probably situated on the surface of the cell membrane, suggests that the racemic mixtures of compounds might not be as effective as a particular one of the optical isomers making up the racemic mixture.
According to the receptor theory of drug activity, the receptors are probably side chains or parts of the macromolecules which make up the cell surface layer. These side chains or parts of molecules have a definite, three-dimensional configuration, and can thus interact only with molecules possessing a complementary configuration. It is known that a relatively minor change in molecular shape can greatly alter the physiological effects of a chemical compound. This may be due to a change in the ability of the particular compound to bind itself to a particular receptor.
Indeed, there are cases known in which the S- and R- forms of optically active pharmacologically effective compounds are known to have different pharmacological effects. It cannot be predicted whether the enantiomers of optically active pharmacologically active compounds will have different effects in a given instance because the properties of the individual receptors are not known in detail, and the mechanisms by which pharmacologically active compounds exert their effects are also generally unknown. Nor can it be predicted which optical isomer will be active, nor how effective it will be in comparison to the optical isomer of opposite rotation or the racemic mixture. Of all presently known optically active drugs, the S- and R- configurations are found in almost equal numbers.
It is also very important to know what isomer is the active one in those cases where the enantiomers differ in effectiveness. Inactive forms dilute the active form, may be competitive antagonists, and may even have dangerous side effects. For example, the S- form of Ethambutole is an anti-tuberculous agent, while the R- form causes blindness in experimental animals, even at low dosages.
Therefore, one object of the present invention is to provide new optically active forms of 1-4 benzodiazepines.
Another object of the present invention is to provide a process for the preparation of solely a particular optically active form of 1-4 benzodiazepines.
A further object of the present invention is to provide compositions for administration of these useful compounds.
SUMMARY OF THE INVENTION
It has now been found that compounds of formula I ##STR4## having an asymmetric carbon atom in position 3 wherein R 1 is hydrogen, halogen or a nitro or trifluoromethyl group, R 2 is hydrogen or C 1-4 lower alkyl and R 3 is C 1-4 lower alkyl, hydroxy C 1-4 lower alkyl phenyl, hydroxy phenyl, benzyl, hydroxy benzyl, or 3'-methyleneindolyl, can be prepared in the pure 3S form. These compounds have pharmacological activity affecting the central nervous system (CNS) as tranquilizers and have a surprisingly greater effectiveness than compounds of the same formula in the form of racemic mixtures.
It has now also been found that optically active compounds of formula I may be obtained according to the invention by reacting a compound of the formula ##STR5## wherein R 1 and R 2 are as defined previously with a compound of formula ##STR6## wherein R 3 is as defined previously and A is H·HCl, H·HBr tertbutoxycarbonyl (Boc), phthalimido, carbobenzoxy (Cbo), or other protective group, to form an intermediate compound having the formula ##STR7## wherein R 1 , R 2 , R 3 and A are as defined previously.
The intermediate compounds of formula IV are also new compounds.
The protective group A of the compound of formula IV is removed to form a free amino group, which then reacts with the carbonyl group to form the compounds of formula I. According to the invention, the reaction between compounds II and III is carried out in an inert solvent and the elimination of protective group A from compounds of formula IV is accomplished by hydrolysis in an alkaline or acidic medium.
The optically active compounds of formula I according to this invention all occur in the 3S configuration and show a substantially higher pharmacological activity than the optically inactive racemic mixtures of the prior art. This may be explained since, as discussed above, where optically active compounds are concerned, often only one form is active in the human organism, while the other form is inactive. Each medicinal preparation affects, practically speaking, one enzymatic system which is substantially responsible for the resulting effect (as a result of the specific space orientation, these systems only react with compounds of a certain configuration). It can be assured that just one form of the racemic compounds having the general formula I is biologically active, while the other form could be a strong antagonist. The elimination of the antagonistic form results in a multiple increase in the activity, since the antagonistic isomer no longer competes with the biologically active form (during the attachment to the receptor inside the CNS). As a result of this, the compounds according to the invention show at least a 3 to 4 times higher activity, in test animals, when compared with the corresponding racemates.
The prepared compounds are completely new and have not been described previously; as a result of this, the optically active 1,4-benzodiazepines have been synthesized for the first time by the process according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred compounds according to this invention are those in which R 1 is chlorine, R 2 is hydrogen, and R 3 is selected from the group consisting of methyl, benzyl, p-hydroxy benzyl, and isopropyl.
The novel compounds of this invention are synthesized according to the following reaction scheme. ##STR8##
According to the above reaction scheme, a 2-aminobenzophenone (II) is reacted with an alpha-amino acid having a protected amino group (III) in an inert solvent in the presence of a suitable catalyst to form an intermediate benzophenone derivative (IV).
Preferred, novel intermediate compounds of formula IV are those in which R 1 is chlorine, R 2 is hydrogen, R 3 is selected from the group consisting of methyl, benzyl, p-hydroxybenzyl, and isopropyl and A is selected from the group consisting of carbobenzoxy, t-butoxycarbonyl, and H·HBr.
Suitable inert solvents are those which will not cause the optically active amino acid derivative or the intermediate optically active benzophenone derivative to become racemized. Examples of such solvents are methylene chloride and tetrahydrofuran (THF). The catalyst used in the reaction of the 2-amino benzophenone with the alpha-amino acid derivative may be any suitable catalyst which does not cause racemization of the alpha-amino acid or the intermediate product. A preferred catalyst is dicyclohexylcarbodiimide (DCC).
A preferred 2-amino-benzophenones is 2-amino-5-chlorobenzophenone.
Preferred alpha-amino acids having a protective group on the amino group are the Boc-and Cbo-protected alpha-amino acids having the 3S configuration. Examples of such alpha-amino acids are N-Boc-and N-Cbo- derivatives of L-alanine, L-valine, L-threonine, L-phenylalanine, L-tyrosine, and L-tryptophane.
Representative intermediate compounds of formula IV having a Boc or Cbo protective group are listed in Table I.
Intermediate compounds of formula IV having a Boc or Cbo protective group may be further converted to an intermediate compound having formula IV wherein group A is H·HCl or H·HBr. These further intermediate compounds may be isolated and characterized. Representative intermediate compounds having formula IV of this type are listed in Table II.
The Boc and Cbo protective groups may be removed by hydrolysis or hydrogenolysis. The hydrolysis is conveniently carried out using a 3% solution of hydrobromic or hydrochloric acid in glacial acetic acid (HAC) when the protective group is Cbo. However, 48% hydrobromic acid in glacial acetic acid can also be used. The Cbo group may also be removed by hydrogenolysis in a suitable inert solvent using 10% palladium supported on carbon as a catalyst. The Boc group is preferably removed with glacial acetic acid or a mixture of glacial acetic acid containing concentrated hydrochloric acid.
After the protective group has been removed, the intermediate compound may be isolated as the acid salt (compound of formula IV wherein group A is, for example, H·HBr) or the free base by conventional procedures of extraction and crystallization and subsequently cyclized, or the amino compound may be cyclized in basic solution without isolation in crystalline form. The cyclization takes place in an inert solvent under mildly basic conditions and at a relatively low temperature. The mild conditions are used to prevent racemization of the intermediate compound or product. Inert solvents are those which do not cause racemization of the intermediate or product. Organic, aqueous, and aqueous-organic solvents may be used. Examples of suitable solvents include water and methanol-water (1:1) mixtures and dioxane-ethanol mixtures. Likewise, the temperature used for the cyclization reaction should be low enough to avoid racemization, and preferably no higher than 40° C.
When the Boc or Cbo protective group is removed by hydrogenolysis in a suitable inert solvent, the cyclization may take place concurrently with the hydrogenolysis. In this way, the removal of the protective group and cyclization can be carried out in a single step.
The pharmacalogical activity of the novel compounds of this invention was evaluated by standard methods such as the anticonvulsant effect against pentylene tetrazole shock and maximal and minimal electroshock, muscle relaxing ability, the fighting test, and hypnotic effect. These standard tests are described in detail in the literature, for example, in L. O. Randall, C. L. Schenkel, R. F. Banziger, Curr. Ther. Res., Clin. Exp., 590 (1965), and M. I. Gluckman, Curr. Ther. Res., Clin. Exp., 7,721 (1965).
The novel compounds of this invention were found to have substantially higher pharmacalogical activity than the corresponding racemic mixtures.
The compounds of this invention may be administered in pharmaceutical compositions in combination with any suitable pharmaceutical vehicle. Thus, they may be administered as solutions, in capsules, tablets, and the like. Suitable formulations for pharmaceutical preparations containing the customary vehicles, adjuvants, and the like, may be taken from standard pharmaceutical reference works such as the U.S. Pharmacopoeia.
The following examples will illustrate the practice of this invention, but are not intended to limit its scope.
In these examples all melting points were determined on a Kofler-Mikroheiztish, and are uncorrected. Ir spectra were obtained on a Perkin Elmer Model 131 Spectrophotomer; uv spectra measurements were performed on a Zeiss Opton PMQ II Spectrophotometer; nmr spectra were obtained on a Varian A-60 or Varian T-60 apparatus using TMS (0.00 Hz) or Silicone grease (4.0 Hz) as internal standard. Rotations were measured on a Perkin Elmer Model 141 apparatus. Thin-layer and column chromatography were performed with the materials and by methods described in V. Sunjic, F. Kajfez, D. Kolbah and N. Blazevic, Croat. Chem. Acta, 43,205 (1971). Light petroleum refers to the fraction b.p. 40°-60°.
The novel optically active compounds of formula I may also be prepared by the method described in Assignees' copending U.S. application by Kajfez, Ser. No. 492,912 filed July 29, 1974.
Examples 1 through 9 illustrate the synthesis of intermediate compounds of formula IV according to the invention, wherein R 1 =C1, R 2 =H, and R 3 is varied. The yield of each synthesis, the melting point of the product, the optical rotation [α] at wavelengths of 578 and 546 nanometers (with solvents and concentrations), and the elemental analyses are tabulated in Table I.
EXAMPLE 1
In 20 ml of methylene chloride 5.08 g (22.0 mmoles) of 2-amino-5-chloro-benzophenone and 20.0 mmoles of N-Boc-L-alanine were dissolved. Dicyclo-hexylcarbodiimide (DCC) (4.49 g, 22.0 mmoles) dissolved in 20 ml of methylene chloride was added to this solution, dropwise during 1 hour at 0° C. and with stirring. After additional stirring at room temperature for 8 hours, the dicyclohexylurea formed was suctioned off and the filtrate evaporated to dryness. The residual crude product was recrystallized from cyclohexane to give 6.95 g of the compound of formula IV having R 1 =Cl, R 2 =H, R 3 =CH and A=Boc. The crude melting point was 150° C.-154° C. Two further recrystallizations from the same solvent gave the analytically pure sample, m.p. 154°-155° C.
EXAMPLE 2
By the procedure of Example 1 except that N-Boc-L-phenylalanine was used in place of N-Boc-L-alanine, the crude compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =CH 3 -C 6 H 5 was prepared. The crude compound was purified by column chromatography (320 g of silica gel. ether-methylene chloride 1:1 as eluent). Fractions of 10 ml each were collected and fractions 11-27 gave 7.50 g of the compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =CH 2 --C 6 H 5 , m.p. 132°-137° C. Recrystallization from cyclohexane gave the analytically pure sample, m.p. 137°-139° C.
EXAMPLE 3
By the procedure of Example 1, except that N-Boc-L-tyrosine was used in place of N-Boc-L-alanine and 30 ml of dried tetrahydrofuran was used in place of the methylene chloride solvent, the crude compound of formula IV wherein R 1 Cl, R 2 =H, and R 3 =p-hydroxybenzyl was prepared. The crude product was purified by recrystallization from cyclohexane (900 ml). The compound crystallized as a voluminous precipitate which was filtered off with difficulty, m.p. 150°-156° C. An analytically pure sample was obtained by column chromatography (ether as eluent), m.p. 158°-160° C.
EXAMPLE 4
By the reaction procedure of Example 3, except that N-Boc-L-tryptophane was used in place of N-Boc-L-tyrosine, a reaction mixture containing the crude compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =3'-methyleneindolyl, and A=Boc was prepared. The crude product was separated from the reaction mixture by column chromatography (360 g of silica gel, methylene chloride-ether 10:1 as eluent). Fractions having a volume of 30 ml each were collected, and fractions 24-37 gave 6.52 g of the chromatographically pure compound. Recrystallization from benzene-light petroleum gave the pure sample with m.p. 152°-154° C.
EXAMPLE 5
By the reaction procedure of Example 3, except that N-Boc-L-threonine was used in place of N-Boc-tyrosine, a reaction mixture containing the crude compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =threnyl, and A=Boc was prepared. The reaction mixture was then subjected to column chromatography on a column of 300 g of silica gel. Elution with 500 ml of methylene chloride gave 4.12 g of starting 2-amino-5-chlorobenzophenone and DCC. Thereafter, a mixture of methylene chloride-ether (4:1) was used, and 7.2 grams of the crude compound were obtained. After recrystallization from ether-light petroleum, the pure sample melted at 67°-70° C.
EXAMPLE 6
By the reaction procedure of Example 1, except that N-Boc-L-valine was used in place of N-Boc-L-alanine, the reaction mixture containing the crude compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =isopropyl, and A=Boc was prepared. The crude reaction mixture was applied to a column containing 350 g of silica gel. By elution with methylene chloride (500 ml), 4.65 g of a mixture of starting 2-amino-5-chlorobenzophenone and DCC was separated. Elution with methylene chloride-ether (10:1) gave 6.4 g of the mixture of the crude compound and by-products. This mixture was separated on a second column (220 g of silica gel, light petroleum-methylene chloride-ether, 10:5:1, as eluent). There was obtained 5.08 g of the chromatographically pure compound as a viscous oil which after crystallization from cyclohexane had a m.p. 106°-108° C.
EXAMPLE 7
Starting with 33.5 g (0.15 mole) of N-Cbo-L-alanine, 27.7 g (0.12 mole) of 2-amino-5-chlorobenzophenone and 30.7 g (0.15 mole) of DCC the same general reaction procedure as in Example 1 was followed and the crude compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =methyl, and A=Cbo was obtained by crystallization from 210 ml of hot cyclohexane, m.p. 144°-147° C.
EXAMPLE 8
By the procedure of Example 7, except that N-Cbo-L-phenylalanine (45.0 g, 0.15 mole) was used in place of N-Cbo-L-alanine and the crude product was recrystallized from cyclohexane-ether (20:1) instead of cyclohexane; the compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =benzyl and A=Cbo was prepared.
EXAMPLE 9
31.5 g (0.10 mole) of N-Cbo-L-tyrosine, 0.10 mole of DCC, and 0.09 mole of 2-amino-5-chlorobenzophenone were reacted by the general procedure of Example 1 using absolute T H F as a solvent instead of methylene chloride. The compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =p-hydroxybenzyl, and A--Cbo was isolated from the crude reaction mixture by column chromatography (600 g of silica gel). By elution with methylene chloride (150 ml) unconverted amine and DCC were separated. Elution with methylene chloride-ether (5:1) gave the crude product which recrystallized from cyclohexane-ether (10:1), m.p. 117°-120° C.
TABLE I__________________________________________________________________________ Elemental Analysis__________________________________________________________________________ Calcd. FoundEx- Yield % %ample R.sub.3 A % M.p.° C. [∝]578[∝]546 Formula C H N C H N__________________________________________________________________________1 --CH.sub.3 Boc 86.4 154-155 -58.5° -68.0° C.sub.21 H.sub.23 ClN.sub.2 O.sub.4 62.61 5.75 6.95 62.48 5.71 6.72 --CH.sub.2 -C.sub.6 H.sub.5 Boc 78.5 137.5-139 -72.0° -85.1° C.sub.27 H.sub.27 ClN.sub.2 O.sub.4 67.70 5.68 5.85 67.71 5.73 5.65 1.196/CHCl.sub.33 --CH.sub.2 -C.sub.6 H.sub.5 -p-OH Boc 61.2 158-160 -66.9° -79.2° C.sub.27 H.sub.27 ClN.sub.2 O.sub.5 64.93 5.82 5.24 64.70 5.62 5.41 0.688/CHCl.sub.34 --CH.sub.2 -3'-indolyl Boc 51.5 152-154 -89.5° -106° C.sub.29 H.sub.28 ClN.sub.3 O.sub.4 67.24 5.45 8.12 67.30 5.21 7.99 1.314/CHCl.sub.35 --CHOH-CH.sub.3 Boc 47.5 79-81 -39.6° -69.0° C.sub.22 H.sub.25 ClN.sub.2 O.sub.5 61.05 5.82 6.47 60.94 5.56 6.34 1.020/CHCl.sub.36 --CH(CH.sub.3).sub.2 Boc 59.0 106-108 -48.3° -57.2° C.sub.23 H.sub.27 ClN.sub.2 O.sub.4 64.12 6.30 6.49 63.90 6.60 6.25 1.118/CHl.sub.37 --CH.sub.3 Cbo 82.5 117-119 -17.8° -22.0° C.sub.24 H.sub.21 ClN.sub.2 O.sub.4 65.99 4.84 6.41 66.31 5.14 6.40 2.180/CHCl.sub.38 --CH.sub.2 -C.sub.6 H.sub.5 Cbo 66.0 115-116 -48.5° -55.8° C.sub.30 H.sub.25 ClN.sub.2 O.sub.4 70.24 4.91 5.46 69.90 4.92 5.24 1.200/CHCl.sub.39 --CH.sub.2 -C.sub.6 H.sub.4 -p-OH Cbo 57.5 117-120 -33.1° -39.3° C.sub.30 H.sub.25 ClN.sub.2 O.sub.5 68.12 4.76 5.30 67.91 4.49 5.17 0.968/Me.sub.2 CO__________________________________________________________________________
Examples 10 through 15 illustrate the synthesis of other intermediate compounds having formula IV wherein the Boc or Cbo protective group has been removed by hydrolysis and replaced by H·HBr. These novel intermdiates are listed in Table II together with their melting points and their optical rotations [α]at wavelengths of 578 and 546 nanometers at given concentrations in the given solvents.
EXAMPLE 10
0.1 moles of (-)-S-5-chloro-2-(carbobenzoxyalanyl)-amino-benzophenone (compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =methyl, and A=Cbo) was dissolved in 120 milliliters of 4 molar HBR/CH 3 COOH while being cooled in an ice bath. After 10 minutes the ice bath was removed and the reaction mixture was allowed to warm to room temperature. The mixture was then stirred until evolution of gas from the solution ceased. The reaction mixture was evaporated to dryness in a rotary evaporator and then with the addition of three 200 milliliter portions of benzene and subsequent evaporation was again dried. The oily residue was crystallized by addition of ether. The crude product was recrystallized from ether-methanol, with the addition of some cyclohexane.
The product was the compound of formula IV wherein R 1 =Cl, R 2 =H, R 3 =methyl and A=H·HBr.
EXAMPLES 11-15
By the procedure of Example 10, starting with the appropriately substituted compound of formula IV in which A=Cbo the corresponding compounds having A=H·HBr and R 1 , R 2 and R 3 as specified in Table II were prepared.
Examples 16 through 19 illustrate the synthesis of intermediate compounds having formula IV wherein A--H·HBr by hydrogenolysis of the compounds of formula IV wherein A--Cbo. These novel intermediates are listed in Table II along with the compounds prepared in Examples 10-15.
EXAMPLE 16
0.1 moles of (+)-S-5-chloro-2-(N-methyl-N-carbobenzoxyalanyl)-amino-benzophenone (compound having formula IV wherein R 1 = Cl, R 2 = methyl, R 3 = methyl, A = Cbo) was dissolved in 150 milliliters of 90% methanol and added to 0.2 to 0.3 moles HBr/CH 3 COOH and 10% Pd-C in a quantity equivalent to 10% of the added material. Then a hydrogenation was carried out in a closed system without significant excess pressure. The course of the reaction was followed by thin layer chromatography until the disappearance of the spot of starting material (ether-chloroform was used as the solution solvent). After the conclusion of the reaction, the catalyst was filtered off and the reaction mixture was evaporated to dryness. The residue was worked up in the same fashion as described in Example 10.
EXAMPLES 17-19
By the procedure of Example 16, starting with appropriately substituted compound of formula IV in which A = Cbo the corresponding compounds having A = H·HBr and R 1 , R 2 , and R 3 as specified in Table II were prepared.
TABLE II__________________________________________________________________________ [α] 578 [α] 546ExampleR.sub.1 R.sub.2 R.sub.3 M.P. ° C c (in CHCl.sub.3)__________________________________________________________________________ -66.7°10 Cl H CH.sub.3 129-131 -66.7° 80.4° 2.364 in H.sub.2 O11 Cl H ##STR9## 240-245 -41.3° -51.1° 1.211 in MeOH12 Cl H ##STR10## 160-165 -38.5° -45.8° 1.586 in MeOH13 Cl H ##STR11## 237-240 + 9.4° + 2.65° 0.748 in MeOH14 Cl H ##STR12## 240-243 -17.1° -21.7° 0.760 in MeOH15 Cl H ##STR13## 112-115 -4.8° -11.20° 0.624 in MeOH16 Cl CH.sub.3 CH.sub.3 165-167 -60.2° -83.5° 2.403 in MeOH17 No.sub.2 H CH.sub.3 172-174 +9.3° -36.3° 1.385 in MeOH18 H CH.sub.3 ##STR14## 248-250 -48.2° -56.2° 1.354 in MeOH19 CF.sub.3 H CH.sub.3 158-160 -35.7° -56.2° - 1.453 in__________________________________________________________________________ MeOH
EXAMPLE 20
A 8.55 g of the compound of formula IV wherein R 1 = Cl, R 2 = H, R 3 = CH 3 and A = Boc were dissolved in 45 ml of acetic acid at 0° C. and 5 ml of hydrogen bromide - acetic acid (4M) was added dropwise. After 5 minutes 50 ml of benzene was added and the reaction mixture evaporated in vacuo. The residual oil was dissolved in 200 ml of ethanol-water (1:1) and the pH adjusted to 8.5 by addition of 5% sodium hydroxide. After stirring overnight at room temperature (not over 25° C.) the solution was partially evaporated in vacuo, 300 ml of water was added and the mixture extracted with 3 × 100 ml of methylene chloride. The organic layer was dried (sodium sulfate), evaporated, and the residual oil recrystallized from 150 ml of acetone-water (1:1). The pure product (compound of formula I wherein R 1 = Cl, R 2 = H and R 3 = CH 3 ) was recrystallized and melted at 200°-203° C. nmr (CDCl 3 ): 1.76 ppm (d, 3H), 3.79 (qv. 1H), 7.3-7.8 (m, 1H), 9.25 (s, 1H). Analysis: calculated for C 16 H 13 ClN 2 O (284.74): C, 67.49; H, 4.61, N, 9.84. Found C, 67.21; H, 4.88; N, 9.54.
B. 21.75 g (0.05 mole) of the compound of formula IV wherein R 1 --Cl, R 2 = H, R 3 = CH 3 and A = Cbo were dissolved in 150 ml of a mixture of dioxane and ethanol (2:1) and 2.0g 10% Pd - C were added. Flow hydrogenation was performed during 6 hours after which time no starting material was present and thin-layer chromotography indicated that about 80% of the free amine had cyclized. The catalyst was filtered off, the filtrate was evaporated in vacuo and the residual oil was recrystallized, yielding 12.8 g of the compound of formula I wherein R 1 = Cl, R 2 = H, R 3 = CH 3 , having the same physical constants as the compound prepared by method A.
EXAMPLE 21
By the method of Example 20B except that the compound of formula IV having R 1 = Cl, R 2 = H, R 3 =benzyl, A = Cbo was used as the starting material the compound of formula I having R 1 = Cl, R 2 = H and R 3 = benzyl was prepared.
EXAMPLE 22
By the procedure of Example 20A except that the compound of formula IV wherein R 1 = CH 3 , R 2 = H, R 3 = p-hydroxybenzyl, and A = Cbo was used as the starting material, the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = p-hydroxybenzyl was prepared. The crude product was purified by column chromatography (ether-petroleum ether, 3:1 as eluent) followed by recrystallation from ether-cyclohexane.
EXAMPLE 23
By the procedure of Example 20A, except that the compound of formula IV wherein R 1 = Cl, R 2 = H, R 3 = 3'-methyleneindolyl and A = Boc was used as the starting material, the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = 3'-methyleneindolyl was prepared. The product was recrystallized from ether. One mole of ether included in the crystallized product could not be removed even after prolonged drying at 80° C. and 0.01 mm of mercury over phosphorus pentoxide.
EXAMPLE 24
By the procedure of Example 20A, except that the compound of formula IV wherein R 1 = Cl, R 2 = H, R 3 = 1'-hydroxyethyl, and A = Boc was used as starting material, the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = 1'-hydroxyethyl was prepared. The compound was purified by column chromatography (petroleum ether-methylene chloride-ether, 1:2:4 as eluent).
EXAMPLE 25
By the procedure of Example 20A, except that the compound of formula IV having R 1 = Cl, R 2 = H, R 3 = isopropyl and A = Boc was used as the starting material, the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = isopropyl was prepared. The compound was recrystallized from petroleum ether-methylene chloride (40:1).
EXAMPLE 26
10.0 g of the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = CH 3 were dissolved in 40 ml of dimethyl formamide (DMF) under nitrogen. Anhydrous barium oxide (2.0 g) was added and 3 ml of methyl iodide diluted in 10 ml of DMF was added dropwise with stirring during 0.5 hour. After 6 hours stirring the reaction mixture was diluted with 500 ml of water and extracted with three 200 ml portions of methylene chloride. The organic layer was dried (magnesium sulfate) and evaporated. The residual oil was applied to a column (300 g of silica gel) and eluted with methylene chloride (pure) to remove free 2-amino-5-chlorobenzophenone. Elution with ether-methylene chloride gave the compound of formula I wherein R 1 = Cl, R 2 = CH 3 , and R 3 = CH 3 as a viscous oil. The compound was recrystallized from light petroleum.
EXAMPLE 27
By the procedure of Example 26, except that the compound of formula I wherein R 1 = Cl, R 2 = H, and R 3 = benzyl was used as the starting material, the compound of formula I wherein R 1 = Cl, R 2 = CH 3 and R 3 = benzyl was prepared. The compound was recrystallized from light petroleum.
EXAMPLE 28
0.05 moles of the compound of formula IV in which R 1 = NO 2 , R 2 = H, R 3 = methyl and A = H·HBr were dissolved in a mixture of water-ethanol (100 ml:100 ml). 10% sodium hydroxide solution was added until the pH was 8.5 and the mixture was stirred at room temperature or on a water bath at 40° C. The ensuing cyclization reaction was followed by thin layer chromatography (ether-CHCl 3 (1:1) as eluting solvent). After the conclusion of the reaction of the solvent mixture was evaporated in a rotary evaporator and the residue was crystallized from acetone-water solvent mixture.
EXAMPLES 29-31
By the process of Example 28 starting from the appropriately substituted compound of formula IV the compounds of formula I listed in Table III were prepared.
EXAMPLE 32
This Example illustrates the pharmacological effectiveness of the compounds of this invention. A number of the compounds of this invention were tested for their pharmacological effect on the CNS by the procedures described above. Also tested were the corresponding racemic mixtures and three commercial tranquillizers:
Diazepam = 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepine-2-one ("Valium"),
Medazepam = 7-chloro-5-phenyl-1-methyl-1,2-dihydro-3H-1,4-benzodiazepine
Oxazepam = 7-chloro-1,3-dihydro-3-hydroxy-5-phenyl-2H-1,4-benzodiazepine-2-one
The results of the tests are shown in Table IV wherein the relative potencies compared with that of chlordiazepoxide which is assigned an activity of 1.00. The larger the numerical values, the less effective is the tranquillizing power in the given test. From the results presented in Table V, it can be seen that the racemic mixtures are typically 6-10 times less effective than the pure optical isomers of this invention. It can also be seen that the pharmaceutically active compounds of this invention compare favorably with some commercially useful tranquillizers and even surpass them in some respects.
TABLE III__________________________________________________________________________ [α] 578 [α] 546ExampleR.sub.1 R.sub.2 R.sub.3 M.P. ° C. c (in CHCl.sub.3)__________________________________________________________________________ +172.5°20 C1 H CH.sub.3 200-203 +201° 2.49221 Cl H ##STR15## 108-110 +51.8° +58.4° 0.52022 Cl H ##STR16## 139-141 +42.5° +502° 0.60023 Cl H ##STR17## 150-152 +40.4° +48.3° 1.068 +154°24 Cl H CHOH CH.sub.3 118-121 +179° 1.088 +148°25 Cl H CH(CH.sub.3).sub. 2 192-194 +171° 1.116 +212°26 Cl CH.sub.3 CH.sub.3 47-50 +249° 0.85227 Cl CH.sub.3 ##STR18## 135-137 +98.9° +116.0° 1.388 +132.5°28 NO.sub.2 H CH.sub.3 96-98 +177° 0.67429 H CH.sub.3 ##STR19## 135-137 +98.9° +116° 1.388 +74.6°30 CF.sub.3 H CH.sub.3 87-90 +99.8° 0.89231 Cl CH.sub.3 OCH.sub.2 CHOHCH.sub.2 OH__________________________________________________________________________
TABLE IV__________________________________________________________________________Pharmacological potencies of Benzodiazepines in various tests in mice(Relative Potencies in Comparison with Chlordiazepoxide)__________________________________________________________________________Anticonvulsant effectCompound Maximal Minimal of Pentylene electro electro Muscle Fighting Hypnotic LD 50Example tetrazole shock shock relaxation test effect P.O.__________________________________________________________________________20 (S) 4.1 1.32 0.20 1.0 1.0 0.4 230020 (Rac.) 30.40 8.20 5.00 9.60 10.4 2.3021 (S) 5.30 4.82 2.30 4.10 4.50 2.10 160021 (Rac.) 40.50 10.30 20.60 40.70 45.8 10.7022 (S) 7.3 6.30 1.42 4.30 5.70 4.20 185022 (Rac.) 75.6 65.40 16.70 46.20 56.30 18.6023 (S) 3.20 4.10 1.70 6.20 7.10 0.80 230023 (Rac.) 30.60 38.70 14.60 60.50 80.30 8.3024 (S) 10.30 1.30 0.45 0.62 1.70 0.51 600024 (Rac.) 105.60 12.60 3.27 5.42 16.30 3.2025 (S) 1.80 1.75 0.30 1.15 1.40 0.80 185025 (Rac.) 20.4 20.30 4.70 8.60 9.30 4.2026 (S) 5.80 0.90 0.10 0.70 1.00 0.80 260026 (Rac.) 47.30 10.20 2.10 6.54 8.94 2.7031 (S) 10.30 0.38 0 0.80 1.0 0.42 600031 (Rac.) 105.4 4.72 2.30 9.60 8.74 2.30__________________________________________________________________________Diazepam 6.7 5.20 1.73 3.30 4.3 1.75 800Medazepam 6.2 1.03 0.32 1.3 1.0 0.30 1420Oxazepam 12.3 2.1 0.77 0.62 1.3 0.48 3700__________________________________________________________________________ | Compositions, useful as tranquilizers containing, as active ingredient, an optically active compound having the formula: ##STR1## having an asymmetric carbon atom in position 3 having the S configuration and wherein R 1 is selected from the group consisting of hydrogen, halogen, nitro, and trifluoromethyl groups, R 2 is selected from the group consisting of hydrogen and C 1-4 lower alkyl groups and R 3 is selected from the group consisting of C 1-4 lower alkyl, hydroxy C 1-4 lower alkyl, phenyl, hydroxyphenyl, benzyl, hydroxybenzyl, and 3'-methyleneindolyl groups, is described.
They are obtained by reaction of a compound having the formula ##STR2## with a compound of the formula wherein A is a protective group.
The compounds of formula I have sedative and tranquilizing properties. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority from German Application No. 19732839.3, filed on Jul. 30, 1997, the subject matter of which is hereby incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a method of isolating 1- N 2 -((S)-ethoxycarbonyl) -3-phenylpropyl) -N 6 -trifluoroacetyl!-L-lysyl-L-proline (LPE, compound I). ##STR1##
BACKGROUND OF THE INVENTION
N-substituted amino acids of this type are valuable intermediate products for the production of inhibitors of angiotensin-converting enzyme (ACE), which act as regulators of blood pressure. The compound of formula (I) is the direct intermediate product for 1- N 2 - ((S) -carboxy) -3-phenylpropyl)!-L-lysyl-L-proline (Lisinopril II), which exhibits superb therapeutic results in combating high blood pressure (Zestril®, Coric®, Prinivil®).
Compound (I) is obtained according to the state of the art by the reductive amination of 2-oxo-4-phenyl-ethyl butyrate with the dipeptide Lys (Tfa)-Pro. ##STR2##
Such a method is described in the J. Org. Chem. 1988, 53, pp. 836-844. According thereto, compound (I) is obtained in a yield of 42% by basic extraction of the raw reaction solution, a subsequent extraction of the product in methylene chloride at pH 4.6 and, after a change of solvent, crystallization from methyl-tert.-butyl ether, cyclohexane.
EP 05 23 449 concerns the synthesis of compound (I) obtained according to example 3 with a yield of 60%. The workup of the raw reaction solution obtained according to this method contains, in addition to the basic and an acidic extraction step with 1,1,1-trichloroethane, a crystallization from methyl-tert. butyl ether.
In principle, other methods for producing compound (I) are also known which are not based on reductive amination but are less advantageous (EP 0 336 368 A2). The aqueous product phase is extracted therein with methylene chloride. However, after drying of the organic phase over sodium sulfate the solvent is again changed for crystallization in methyl-tert.-butyl ether.
The crystallization from pure methyl-tert.-butyl ether results in a crystal grain which is difficult to filter and in yields which are frequently insufficient (EP 0 645 398 A1). If compound (I) is allowed to crystallize out of solutions with a high concentration an additional recrystallization becomes necessary. The addition of cyclohexane (J. Org. Chem., 1988, 53, pp. 836-844) during the crystallization for increasing the yield is also described. However, there is the danger of a separation as oil, which makes it much more difficult to isolate the product, not only on an industrial scale.
EP 0 645 398 A1 extensively examines the possibility of the crystallization of compound (I) from various solvents or solvent mixtures. It is shown therein that when methyl-tert.-butyl ether or mixtures containing methyl-tert.-butyl ether are used the residual solvent content of the crystals is very great after the crystallization and residual solvent is bound in the crystal. The LPE raw material obtained in this manner is extremely difficult to dry. Long drying times which can adversely affect the product quality (formation of DKP, especially at elevated temperatures) and the tendency of the product to agglutinate makes special, expensive drying procedures necessary
WO 95/07928 teaches a type of workup which describes an extraction with subsequent crystallization. The raw material of the LPE production is pre-cleaned in a pH range of 0-6.3, if necessary by means of several liquid/liquid extraction steps before it is crystallized out of a mixture of methyl-tert.-butyl ether and methyl cyclohexane at reduced temperatures. A solvent exchange also takes place between the extraction and the crystallization.
A disadvantage of the methods of the state of the art for working up LPE is the fact that frequently environmentally hazardous chlorinated solvents are used and the solvent must be replaced during the workup. This is difficult to achieve completely on an industrial scale and as a result of which only insufficiently defined solvent compounds can be adjusted for the crystallization. In addition, only mild temperature conditions are permitted for such solvent changes on account of the sensitivity of the product, which entails long distillation times. Moreover, the methods of the state of the art often result in crystals which are difficult to filter and much residual solvent is included therewith. Such a product requires long drying procedures which make it difficult to control caking and agglutination on an industrial scale.
SUMMARY OF THE INVENTION
In view of the state of the art indicated and discussed herein, the invention therefore has the purpose of finding a novel method for isolating LPE (I) which permits the raw material obtained from an LPE production process to be better isolated from an aqueous product phase with a simplified and more economic process, which for its part helps reduce the customary long drying times which stress the LPE (I) and more favorable crystalline properties of the precipitated material are obtained.
The invention also has the purpose of generating an end LPE material using the novel, simpler isolating methods which end material is improved over that of the state of the art with comparable drying times, especially as concerns the residual solvent content.
The invention also has the purpose of providing an improved LPE (I).
As a result of the fact that LPE (I) is extracted with a solvent or solvent mixture from an aqueous product solution of an LPE production process produced according to the method of the state of the art and that this solvent or solvent mixture is subsequently used as a main component of the solvent or solvent mixture from which the LPE (I) is crystallized, crystals of LPE distinguished by more advantageous crystalline properties are obtained by this simplified and much more economic method. The LPE generated in this manner exhibits only slight solvent inclusion after crystallization and possesses excellent filterability on account of its well-formed crystalline structure. The slight amount of included residual solvent is a reason that the previous long drying times per drying batch can be significantly reduced. The LPE produced in this manner has a byproduct content which is just as excellently low as that of the state of the art. Thus, a product which is more advantageous in comparison to the state of the art can surprisingly be produced in spite of the simplified method of extraction and crystallization of LPE, which is a reason that a more cost-effective method for the production of LPE can be made available.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows, graphically, x-ray diffraction reflexes of LPE (I) of the prior art.
FIG. 2 shows, graphically, x-ray diffraction reflexes of LPE (I) of the subject invention.
DETAILED DESCRIPTION OF THE INVENTION
It is especially advantageous if the novel method for the extraction and crystallization of LPE (I) is carried out with solvents or solvent mixtures consisting of esters and/or ketones of the general formula (III) ##STR3## which solvents or solvent mixtures can be additionally mixed, if necessary, with open-chain aliphatic or cycloaliphatic hydrocarbons as solvent.
The groups R 1 and R 2 therein advantageously stand-for a group of (C 1 -C 6 ) alkyl groups. These groups can be linear or branched. In particular, the groups can contain: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert.-butyl, n-pentyl, n-hexyl. Group R 2 comprises the group of group R 1 and also the group of the (C 1 -C 6 ) alkoxy groups. The latter can also be linear or branched. The following are, in particular, suitable for R 2 : methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, isobutoxy, tert.-butoxy, n-pentoxy, n-hexoxy. The mixing of the solvent or solvent mixture with the hydrocarbons can be carried out before or even after the extraction. These hydrocarbons are open-chain aliphatic hydrocarbons which contain 5-9 C atoms. They can be linear or branched as desired. "Cycloaliphatic hydrocarbons" denotes rings having 5 to 7 C atoms which can be substituted as desired with (C 1-C 4 ) alkyl groups which can be present in branched form. The following have proven to be quite especially advantageous solvents and solvent mixtures:
Esters--Ethyl acetate, n-propyl acetate, n-butyl acetate, ethyl propionate
Ketones--Methyl isobutyl ketone, diethyl ketone, methyl isopropyl ketone
Aliphatics--n-pentane, n-hexane, cyclohexane, methyl cyclohexane.
Higher homologs of the solvents described above are also suitable, with a natural boundary resulting on account of the rising boiling points and therewith a deterioration of the drying properties of the moist crystallizate. Any combination of the above-named, especially advantageous solvents have proven to be especially advantageous solvent mixtures.
These solvents and/or solvent mixtures can also be used with advantage for pre-cleaning the aqueous product phase at a pH between 0 and 3.5. This pre-cleaning takes place before the actual extraction of the LPE (I) in the organic phase, and has the result that the aqueous product phase includes few byproducts. Since the same solvents and/or solvent mixtures can be used which can also be used for the extraction and crystallization, the necessity of making available additional storage capacity for solvents and/or solvent mixtures which differ from those of the extraction and crystallization of the LPE (I) is advantageously reduced. Likewise, this clearly improves the possibility of recycling the solvents. It is consequently always especially advantageous in an industrial process to use as few different solvents as possible.
In addition, an advantageous embodiment of the method can be seen in that an activated carbon purification can be carried out in the same pH range of 0-3.5 after the solvent treatment described above but before the actual extraction of the LPE (I) into an organic solvent or solvent mixture. This again clearly improves the ability of the LPE (I) to be crystallized.
The extraction of the LPE (I) described above from its aqueous product phase is subsequently carried out in a pH range between 3.5 and 6.3, especially preferably 3.9 to 4.8. It is quite especially preferred that the organic solution of LPE (I) obtained in this manner is washed before the crystallization with water at a pH of 4.8 to 6.3 --a range of 5.7 to 6.0 is especially preferred--and that the aqueous phase is separated from the organic phase.
According to the invention the LPE extraction solution can be azeotropically dehydrated before the concluding crystallization, if necessary by distillation. The indicated solvents and solvent mixtures function thereby as water-entraining medium.
The extraction steps discussed above are advantageously carried out at a temperature between 0° C. and 60° C., preferably at 20° C. to 50° C. and especially preferably at 35° C. to 45° C. If solvent mixtures are used volumetric ratios between esters and/or ketones and the aliphatic/cycloaliphatic hydrocarbons used of between 1:0.01 and 1:100, quite especially advantageously 1:0.5 to 1:2 are used. The concluding crystallization takes place according to the invention at temperatures between -40° C. and +50° C. After the crystallization an aliphatic or cycloaliphatic hydrocarbon like that already described in detail above can be added with advantage once more, optionally after the mother liquor has been evaporated to low bulk, to the latter. This results in a new crystallization during which the yields of >75% of LPE (I) which were already high in the past can be increased again by approximately 10%.
The present invention also comprises a novel LPE (I) distinguished by a novel and advantageous crystal modification. LPE (I) produced according to the prior state of the art exhibits a completely different X-ray diffraction behavior than one obtained according to the present invention. Significant new, different reflexes in an X-ray diffraction of the novel LPE (I) in a transmission diffractometer manufactured by STOE/Darmstadt are shown in Table 1.
TABLE 1______________________________________ No. 2 Theta______________________________________ 1 6.7241 2 9.4851 3 11.9034 4 16.3074 5 17.8722______________________________________
Diffractometer: Transmission
Monochromator: Curved Ge (111)
Wavelength: 1.540598 Cu
Detector: Curved PSD
Scan mode: Transmission/stationary PSD/fixed omega 2Theta scan
The reflexes shown in Table 1 have a relative intensity of ≧ 30% of the main reflex at 21.2663. The tolerance of the 2Theta values is maximally ±10%. A deviation of ±5% is preferred and the uncertainty is quite especially preferred at ±1%. However, errors of not greater than ±0.02 units usually occur in apparatus which has been properly adjusted and calibrated.
FIGS. 1 and 2 contrast the X-ray diagrams of two LPE specimens. FIG. 1 shows the reflexes of an LPE (I) produced according to the state of the art (method according to EP 0 719 279, comparative Example 1, completely dried product). FIG. 2 shows results from a specimen obtained according to Example 8 of the present invention. However, all X-ray diagrams of the specimens of examples 2-10 show equal reflex distributions and equal relative intensities.
This novel crystal modification has the result that the LPE (I) can be filtered especially well.
According to the invention the drying times of the LPE (I) produced in this manner are significantly below those of the state of the art. The finding of the novel crystal modification was therewith causal for the possibility of being able to carry out the LPE production method in an economically more advantageous manner.
The following non-limiting examples are intended to clarify the invention.
COMPARATIVE EXAMPLE 1
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated for 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 5° C. in the aqueous phase and the latter extracted with 400 ml ethyl acetate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was largely evaporated to low bulk in a vacuum at max. 33° C. bottom temperature. The bottom was mixed with 125 ml toluene and evaporated further to low bulk to 120 g. Thereafter, 240 ml methyl-tert.-butyl ether were added and cooled down to +4° C. A crystalline precipitate was produced thereby. To this crystalline suspension, 50 ml methyl cyclohexane were added dropwise at 4° C. within 3 h. The mixture was then agitated 1 h, filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 67.7 g (85.2% of theoretical)
Analytics:
______________________________________ (α)25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (° C.) (mg/kg) (degrees)______________________________________92.0(+-0.4) n.d. 6400 toluene -24.0 49100 methyl-tert.- dibutyl ether 770 methyl cylcohexane______________________________________ (n.d. = not determined)
EXAMPLE 2
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated for 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml ethyl acetate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation 235 ml methyl cyclohexane were added to the organic phase and evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 290 g. The bottom was cooled down to -5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 48.0 g (60.5% of theoretical)
Analytics:
______________________________________ (α)25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (° C.) (mg/kg) (degrees)______________________________________98.3(+-0.3) 85-90 n.n. ethyl acetate -25.2 126 methyl cyclohexane______________________________________ (n.n. = cannot be demonstrated)
EXAMPLE 3
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated for 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml ethyl propionate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation 225 ml methyl cyclohexane were added to the organic phase and evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 270 g. The bottom was mixed with 250 ml methyl cyclohexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 59.9 g (75.4% of theoretical)
Analytics:
______________________________________ (α)25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (° C.) (mg/kg) (degrees)______________________________________96.8(+-0.8) 87-90 <20 -25.5 ethyl propionate- 598 methyl cyclohexane______________________________________
EXAMPLE 4
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml n-propyl acetate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation 300 ml n-hexane were added to the organic phase and evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 240 g. The bottom was mixed with 206 ml n-hexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 54.8 g (69% of theoretical)
Analytics:
______________________________________ (α)25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (° C.) (mg/kg) (degrees)______________________________________97.0(+-0.6) 87-91 <20 n-propyl -25.4 acetate 43 n-hexane______________________________________
EXAMPLE 5
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml ethyl propionate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 230 g. The bottom was mixed with 275 ml cyclohexane and cooled down to +50° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 60.0 g (75.6% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.1N HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________97.4 (+-0.8) 87-91 <20 ethyl -25.3 propionate 524 cyclohexane______________________________________
EXAMPLE 6
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml n-propyl acetate. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH-of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 200 g. The bottom was mixed with 270 ml cyclohexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 56.5 g (71.2% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________97.6 (+-0.2) 87-91 <20 propyl -25.4 acetate 253 cyclohexane______________________________________
EXAMPLE 7
1- N 2 -((S) -ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml methyl isobutyl ketone. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 230 g. The bottom was mixed with 185 ml methyl cyclohexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 56.1 g (70.6% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________97.6 (+-0.6) 87-91 91 methyl isobutyl -25.5 ketone 253 methyl cyclohexane______________________________________
EXAMPLE 8
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 120 ml toluene and 30 ml ethyl acetate the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml methyl isobutyl ketone. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 185 g. The bottom was mixed with 235 ml cyclohexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 60.5 g (76.2% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________98.4 (+-0.5) 87-91 207 methyl isobutyl -25.4 ketone 226 cyclohexane______________________________________
EXAMPLE 9
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously to Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 45 ml methyl isobutyl ketone and 45 ml cyclohexane the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml methyl isobutyl ketone. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 185 g. The bottom was mixed with 235 ml cyclohexane and cooled down to +5° C. A crystalline precipitate was produced which was filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 61 g (76.8% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________98.6 (+-0.4) 87-91 215 methyl isobutyl -25.6 ketone 280 cyclohexane______________________________________
EXAMPLE 10
1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (compound I)
A reductive amination according to patent application EP 05 23 449 is carried out analogously in Example 3, page 10.
Workup:
The reaction solution, for which the dosage for the workup was selected in such a manner that in addition to the typical byproduct profile altogether 150 mmol of the desired LPE-(SSS)-diastereomer (I) were in it, was largely concentrated by evaporation in a vacuum at 45° C. bath temperature. The residue was taken up in 1400 ml water and briefly stripped in a vacuum. After the addition of 45 ml methyl isobutyl ketone and 45 ml cyclohexane the pH was adjusted with concentrated hydrochloric acid to 1. The mixture was then agitated 10 min. and the phases subsequently separated. A pH of 4 was now adjusted at 40° C. in the aqueous phase and the latter extracted with 450 ml methyl isobutyl ketone. The phases were separated, the organic phase mixed with 110 ml water and adjusted with sodium hydroxide solution (50%) to a pH of 5.8. After phase separation the organic phase was evaporated to low bulk in a vacuum at max. 40° C. bottom temperature to 160 g. The bottom was mixed with 175 ml cyclohexane and cooled down to +5° C. A crystalline precipitate was produced thereby. To this crystalline suspension, 103 ml. cyclohexane was added dropwise at 5° C. within 1.5 hr. The mixture was then agitated for 1 hr., filtered, washed and subsequently dried in an oil pump vacuum 4 h at RT.
Yield: 66.0 g (83.1% of theoretical)
Analytics:
______________________________________ (α) 25/DSSS diastereomer (c = 1 MeOH/content Melting point Residual solvent 0.IN HCl)(% by weight) (°C.) (mg/kg) (degrees)______________________________________97.4 (+-0.3) 87-91 167 methyl isobutyl -25.6 ketone 218 cyclohexane______________________________________ | A method of isolating 1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (lisinopril (TFA) ethyl ester, LPE). The solvent or solvent mixture used for the extraction is also a main constituent of the solvent or solvent mixture from which the crystallization takes place. High yield as well as good purity of the end product are obtained, without distillation. 1- N 2 -((S)-ethoxycarbonyl)-3-phenylpropyl)-N 6 -trifluoroacetyl!-L-lysyl-L-proline (lisinopril (TFA) ethyl ester, LPE) is described as a precursor for producing an ACE inhibitor. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a machine and process for producing a laminate structure, and more particularly, it relates to a machine and process for coating a base material, such as a fabric, with a two dimensional layer of fibers, then bonding the fibers to the base material by the use of resin in order to make an impregnated laminate structure. This laminate may be used as is; or, by way of example, it may be further processed such as by applying a color coating to each side of the material in order to make it into a colored laminate material.
2. Background of the Invention
The manufacturing and processing of laminate materials is well taught in the prior art with thousands of patents and hundreds of books being published on the subject. In fact, in certain specific fields, such as the manufacture of camouflage materials, a laminate structure comprising a base material such as a fabric that has a network of short length, small diameter metal fibers is taught in British Pat. No. 1,258,943. Other such structures wherein other fiber materials are deposited in a two dimensional array on foraminous base materials is also well known in the art. However, nowhere does the art teach an economical and efficient machine or method for making such laminate material with a preselected amount of fibers bonded to the base material. Quite surprisingly, accomplishing this task proved to be quite difficult.
SUMMARY OF THE INVENTION
This invention relates to a machine and method for making a laminate structure with a base foraminous material, such as a porous paper, having a preselected randomly disposed two dimensional fiber layer thereon with the fiber being bonded, such as by a resin, to the base material. The resin may also be used to impregnate part or all of the base material, as desired. The machine used in making this product includes means for unrolling and feeding the base material to a fourdrinier head box wherein a slurry of liquor and fiber is deposited on the foraminous material with the liquor being suction removed. The fibers are bonded to the base material and the bonding agent may be cured. The laminate may be compressed or calendarized prior to inspecting and rewinding. The product made from this machine can be used as a laminate structure or may be further processed, such as by applying to both sides of the material color coats making a material suitable for camouflage garnish. For use of such material as a camouflage garnish see our co-pending application Ser. No. 540,495, filed Jan. 13, 1975 entitled "MACHINE AND METHOD FOR MAKING CAMOUFLAGE NETS."
It is therefore an object of this invention to provide a machine for making a laminate structure comprising a base material with a second layer comprising a two dimensional array of fibers thereon.
It is another object of this invention to provide such a machine wherein the fiber layer is bonded by a cured resin to the base material.
Yet another object of this invention is to provide a machine wherein inspection of the product occurs as the product is being made and in the event of fluctuations in the product the inspection device can automatically or semi-automatically correct the process by a means of feedback system.
Still another object of the invention is to provide a method of making a laminate structure starting with a base material layer, applying a second layer of a two dimensional array of fibers in a preselected amount to the first layer and then bonding the fibers to the material.
And yet another object of this invention is to provide for each a method wherein the fiber layer constitutes from about 0.5% to about 100% by weight of the base material.
The feature of this invention is that the product made by the method and machine described herein can be further processed to be used as a camouflage garnish or numerous other materials such as anti-static fabrics such as uniforms and floor and wall coverings.
Another feature of this invention is that the fiber layer is made of metal fibers having a diameter of approximately 4 to 50 microns.
Yet another feature of this invention is that the bonding agent for securing the fiber layer to the base material layer is a resin which may comprise, after curing, part of the laminate structure.
The above and other and further objects and the features will be more readily understood by reference to the following detailed description and accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block schematic view of the process performed by the machine of this invention;
FIG. 2 is a perspective view of the first part of the machine;
FIG. 2A is the perspective view of the second part of the machine;
FIG. 3 is a semi-schematic side view of the first part of the machine;
FIG. 3A is a semi-schematic side view of the second part of the machine;
FIG. 4 is a schematic view of the piping and tank arrangement;
FIG. 5 is a perspective view of the tension conveyor link;
FIG. 6 is a segmented perspective view of the base material;
FIG. 7 is a segmented perspective view of the base material with a two dimensional array of fibers thereon; and,
FIG. 8 is a segmented perspective view of the resin impregnated laminate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention comprehends as a preferred embodiment a machine and a process for making a laminate material (referring to FIGS. 6, 7 and 8) starting with a foraminous base material 10, for example a porous paper, a woven or knit fabric, a substantially two dimensional non-woven fabric or felt, a a spun bonded synthetic fiber product which includes non-woven products such as CEREX (a trademark product of the Monsanto Corporation) or REMAY (a trademark product of the Dupont Corporation) with a substantially two dimensional layer of randomly oriented fibers 11 deposited on the surface of the material 10 to form a laminate 12. The laminate 12 is then impregnated with a resin 13 to bond the fibers 11 to the base material 10 thus forming a resin impregnated fiber laminate material 14. If desired, the material 14 may then be formed into a compressed laminate material 16 by compression, compaction, calendering, crimping, etc., as desired. The fibers 11 can be organic, natural or metallic filaments and can be of any preselected size of diameter or length. The weight of fibers 11 can be approximately 0.5 to about 100% of the base material. Obviously, since cotton weighs one-seventh as much as stainless steel the weight percentage for stainless steel can be much greater than cotton, yet much fewer fibers might be used. When metal fibers having a diameter of from about 4 microns to about 50 microns are used, they can constitute from about 3 to 20 % by weight of the base material. Preferably when a base material weighting 1.5 oz. per sq. yard is used the metal fibers will be present in about 2% to 8% by weight and most preferably about 3% by weight. In this preferred embodiment the resin content will be from about 10% to 100% by weight of the base material. Preferably when a 1.5 oz. per. sq. yard base material is used, the resin content is most preferably about 33% by weight of the base material. The resin can be selected from (1) water disperesed resins including polyvinyl chloride, nitril rubbers, neoprene, polyvinylidene but not limited thereto; (2) water soluble resins including polyvinyl alcohol, polyvinyl pyrollidone, methyl cellulose; or (3) numerous non-water soluable or dispersible resins. Special care must be taken in using textile metal fibers to insure that the ends of the fibers are not hooked. One technique for providing such metal fibers as taught in copending U.S. patent application Ser. No. 533,988, filed Dec. 18, 1974, entitled PROCESS FOR PRODUCTION OF PRECISION CUT LENGTHS OF METAL FIBERS, and owned by the assignee hereof. It has been found extremely economical and efficient to produce the laminate material 14 or 16 by the method and machine described herein.
The operation of the machine and the process is best understood by reference to FIGS. 1, 2, 2A, 3 and 3A. In one preferred embodiment of the invention a 2,000 to 4,000 yard roll of CEREX non-woven material 10, about 60 inches wide, is placed on spool 20 that is journally mounted on stand support 21. The material 10 passes underneath journaled guide roll 22 to the pre-moisturizer 24 wherein additional journal mounted guide rolls 22 guide material 10 to the pre-moisturizer rollers 28 which submerge the material 10 in the pre-moisturizer pan 26. When the fourdrinier slurry liquor is water and resin is water dispersible material the pan 26 is filled with water. Obviously other solutions and solvents may be used as desired. The material 10 then passes to the slurry deposition section 30 where the fibers 11 are deposited onto the base material 10. The slurry deposition section 30 comprises a fourdrinier head box 32, a fourdrinier screen 34 that continuously and endlessly passes beneath the head box 32 carrying the material 10. The screen 34 is supported by lead-in roller 35 and support rollers 36. The material 10 enters the slurry deposit section 30 inbetween the screen 34 and the head box 32 near the roller 36. As the material 10 passes beneath the fourdrinier head box lip 33, the slurry 50 with the fibers 11 is deposited on the moving material 10 supported by screen 34 in a quasi-flotational manner. Suction boxes 38 rapidly withdraw the water or slurry liquor through the foraminous material 10 and the screen 34 leaving the fibers 11 deposited in a two dimensional array. The now laminate material 12 passes over the resin impregnation roll 42 which is mounted above resin reservoir 44, both being supported by frame 46.
As the laminate material 12 passes over the impregnation roller 42 with resin 13 coating the base material 10 and fibers 11 it is introduced to conveyor 70. Conveyor 70 has special conveyor chains having side chain links 72 with upright needles 76 mounted on needle plate 74 that grip and stretch the material 14 as it proceeds along the conveyor 70. These special links 72 are depicted in FIG. 5 with a section of material 14 shown in the phantom.
Material 14 enters the radiant preheater 78, and in one preferred embodiment the preheater 78 is 4.2 feet long and maintained at a surface temperature of about 1500°F. In this embodiment material 14 is traveling at a speed of approximately 80 feet per minute. When the resin is water soluble or dispersible, then the sides of the preheater can be left opened to the atmosphere and approximately 20% of the water moisture can be removed from the material 14. For resins soluble or dispersible in liquids others than water, normally the preheater will be closed to the atmosphere and a hood will be provided over the preheater 78 so that fumes may be properly removed. Preferably the speed of the material 10 can vary anywhere from 40 to 200 feet a minute depending, in part, upon the type of fiber slurry deposition, the amount of fiber, the type of fiber, the resin coating, and the type of base material. Obviously other variables can affect the speed with which the material 10 travels through the machine.
Even though the material 4 is being pulled partially through the machine by conveyor links 72 of chain 70 in cooperation with the needles 76, the links 72 and the needles 76 also pull the material at approximately 90° to its main direction of travel so that the material is kept very tight and will dry evenly as it continues through preheater 78 and the oven 80. After the material 14 leaves the oven 80 it is removed from conveyor 70 by a stripper finger (not shown) and enters the compression section 82 where a series of heated rolls 83 compress the material to the desired thickness and it becomes a compressed resin impregnated fiber laminate material 16. Alternatively, the material may be calendered, crimped, or corrugated in station 82, as desired. The material then proceeds to the inspection station 84 where it is inspected for such items as the proper fiber density, orientation of fibers, and thickness. The material 16 is then respooled in station 90 so that it may be removed from the machine and further processed, as desired.
Not only can the inspection station 84 inspect the material 16, but it can indicate on the material 16 the portions that do not meet the pre-established standards. The inspection station 84 can cause the fault marker 86 to place an identifiable mark on the substandard portions of the material 16 so that it can be removed from the roll at a later date. If desired, the inspection station 84 can also monitor the density of the fiber deposition from slurry 50 on the material 10 and trigger a light or signal on an indicator board (not shown) that adjustments should be made. Alternatively, inspection station 84 can be connected through the feedback control system 110 with a computer (not shown) directly to the slurry deposition section 30 to control the amount of either new water or concentrate water that comprises the slurry (hereinafter discussed).
In one preferred embodiment of the invention where metal fibers having a diameter of approximately 8 microns and a length of approximately 0.170 inch have been deposited on a non-woven textile material 10 and resin bonded thereto by a copolymer resin of PVC present in about 33% by weight, the fibers comprise about 3% by weight of the base material. The inspection station 84 utilizes three different heads 87 transmitting at 9.375 GHz modulated, respectively, by frequencies of 510 Hz, 1300 Hz, and 2300 Hz in order to check the radar transmission, reflection and polarization of the material 16. These frequencies are generated with a known amount of energy and the sensors 88 measure the amount of energy absorbed and reflected and compare it with a baseline standard in a computer (not shown). If the material 16 is not within tolerance then that portion is immediately marked by the fault marker 86 so that it can be removed later. Obviously, other types of inspections can be made with respect to other physical characteristics of the material as desired.
Referring now to FIG. 4 and a preferred embodiment of the invention where the slurry liquor is water, city water is used to fill up the 10,000 gallon water storage tank 51 by means of pipe 51a. The water from tank 51 is used to fill a 6,000 gallon concentrate tank 54 by closing valve 53a and opening valve 52a letting the water flow through pipe 52. When the tank 54 is filled to the desired level, valve 52a is closed and valve 53a is opened so that tank 55 may be filled to the desired level through pipe 53. In one preferred embodiment of the invention, 8 micron stainless steel fibers each having a length of 0.170 inches are added to the tank 54 in the ratio of 0.55 grams of fibers per gallon of water. The mixer or beater 54 is turned on to form a uniformly mixed slurry 50 of meatl fibers and water. By closing valve 55b and opening valve 54b the slurry liquor can be pumped by constant flow pump 56 through pipe 57 to the mixing chamber 58. New or city water is added at the pump 56 diluting the concentrate slurry from tank 54 to 55. The fiber density monitor 56 senses the amount of fiber in the slurry in pipe 57 and automatically adjusts the valve 56b controlling the amount of new water in order to change, when necessary, the fiber concentration level of the slurry. A special controllable metering valve 57a is provided between the pump 56 and the mixing chamber 58 in order to control the rate of flow to the chamber 58. The valve 57a may be operated either automatically or manually, as desired. Water from recirculating tank 60 is added to the mixing chamber 58 by opening controllable metering valve 60b (operated either automatically or manually, as desired) so that recirculating water may flow through pipe 60a into the mixing chamber 58. In the mixing chamber 58 a proper amount of recirculating water is added to a preselected amount of concentrated slurry from tank 54 or 55 to dilute the slurry to the desired consistency prior to its passing through pipe 59 into the head box 32.
As the concentrated slurry is being used from tank 54, tank 55 with a second batch of concentrated slurry is prepared so that when tank 54 is empty valve 54b is closed and valve 55b opened and the slurry from tank 55 is used. Thus it is possible to oscillate back and forth between tank 54 and tank 55 so that a constant source of concentrated slurry is always available. After the slurry 50 is deposited on the material 10 the liquor or water portion of the slurry is removed from the material 10 by means of vacuum suction pumps 61 and 62 that are attached to the suction boxes 38. The water withdrawn by pumps 61 and 62 is combined and charged back into the recirculating tank 60 by means of pipes 61a and 62a feeding into pipe 63. In the event that there is an excess of recirculating water at any one time in the system, it can be discharged by pump 64 through pipe 64a into water storage tank 51.
As previously discussed it is possible to couple the control portion of the inspection station 84 to the valves 56a, 57a and 60b to form part of a feedback system so that the flow of the recirculating water, the new water and the concentrate slurry may be varied with respect to each other by means of valves 56a, 57a and 60b thereby altering the amount of fiber 11 that is deposited on the material 10. Also by use of a computer (not shown) that is coupled to inspection station 84 and the screen 34 drive motor (not shown) a second feedback control system may be formed to alter and adjust the speed of the respooling station 90. Thus it is possible to vary the amount of fiber deposition on the material 10 by two different feedback systems by employing the monitoring portion of inspection station 84 and a computer coupled with the screen 34 drive motor or the slurry valving.
By use of the machine and method described herein above, one is able to economically, efficiently and automatically produce a compressed resin impregnated fiber laminated material. By varying the amount of resin, the fiber layer and starting base material any reasonable degree of porosity (or no porosity) may be obtained in the final material. Although specific embodiments of the invention have been described, many modifications and changes may be made in the machine or the process without departing from the spirit and scope of the invention as defined by the appended claims. | This invention comprehends a machine for producing a composite laminate structure wherein one layer is a base material, such as a non-woven fabric, a second layer, interspersed with the first layer, is substantially a two dimensionally randomly oriented fiber layer. The fibers are bonded to the first layer by resin which is applied from underneath the first layer so as not to disturb the orientation of the fibers. Also comprehended is a method of making such a composite laminate structure. | 3 |
FIELD OF THE INVENTION
This invention relates generally to infusion devices and, more particularly, to an actuator for use in an infusion device drive mechanism, the actuator being configured to facilitate periodic cleaning of the infusion device and to generally improve fluid flow from the infusion pump's inlet reservoir to the pump's outlet chamber.
BACKGROUND OF THE INVENTION
Infusion devices may be used to deliver an infusion media (e.g. a medication such as insulin) to a patient. Such devices may be designed to be implanted into a patient's body to deliver predetermined dosages of the infusion media to a particular location within the patient's body; e.g. in the venous system, the spinal column, or within the peritoneal cavity.
A known infusion device of the type described above includes a drive mechanism that includes a reciprocating pumping element made of a ferrous material. The reciprocating pumping element includes an actuator including a piston portion that is coupled to an armature portion. The piston portion is configured to reciprocate within a piston channel when a solenoid coil is alternately energized and de-energized. That is, when the solenoid is energized, magnetic flux causes the actuator to move very quickly (i.e. in the order of 2-3 milliseconds) until it reaches a stop member. This corresponds to the pump's forward stroke and results in the delivery of a predetermined dosage of infusion media from an outlet chamber to the patient. When the solenoid is de-energized, the lack of magnetic flux allows the actuator to return to its original position under the force of a spring. This, in turn, causes the pressure in the piston chamber to fall. The reduced pressure in the piston chamber causes infusion media to flow from a reservoir through an annulus between the actuator piston and the piston cylinder wall to refill the piston chamber thus equalizing the pressure between the reservoir and the piston chamber and preparing the pump for its next pumping or delivery stroke. This is referred to as the refill stroke. The annulus between the actuator piston and the piston cylinder is very small (i.e. in the order of 150 to 250 microinches radially) resulting in an outlet chamber refill process that takes between about 1 to 2 seconds. In contrast, the pump's forward (delivery) stroke may be approximately 500 times faster than the refill process.
Over time, protein drugs such as insulin denature resulting in the deposition of protein on the surfaces of fluid paths; for example, on the surfaces that form the annulus between the actuator piston and the pistol cylinder. Such deposits may cause valves to leak, impede the motion of moving parts, and/or otherwise degrade device performance. Typically, such deposits are removed periodically (e.g. once per year) by rinsing the implanted pump with a solvent (for example, sodium hydroxide (NaOH)) causing the deposits to dissolve.
The rinsing procedure is typically performed as follows. The infusion device's reservoir is first filled with a desired buffer or rinsing solution. Since the device is implanted near the patient's skin, the reservoir may be filled utilizing a first syringe. A second syringe engages the device's outlet to produce a negative pressure differential and therefore help pull the fluid through the pump. The pump itself is operated during this procedure to assist fluid flow through the pump. In the case of insulin, it is an established goal that the rinsing procedure should result in the transport of at least 1 cc of rinsing fluid from the inlet reservoir to the pump's outlet in approximately ten minutes. Rinse cycles less than ten minutes in duration may result in failure to dissolve all deposits, and rinse cycles greater than ten minutes may result in undue discomfort to the patient. The rinse procedure may include a multi-stage operation that involves emptying and refilling the pump's reservoir several times with different fluids, and different drug therapies may require the use of different rinsing agents. It is to be understood that other protein drugs may require different rinse times and/or volumes.
As previously stated, the space or annulus between the surface of the actuator piston and the piston cylinder wall is approximately 150-200 micro-inches radially, a fairly tight fit, and it takes approximately 1 to 2 seconds to refill the piston chamber via this annulus. Deposits of the type described above that form on the annulus walls will restrict fluid flow thus increasing the time it takes to refill the piston chamber, which, in turn, lowers the stroking frequency and causes the corrective rinse procedure to be protracted; e.g. it could take 30 minutes or more instead of the desired 10 minutes. The deposit build-up could be so extreme so as to cause the pump to jam. In this case, it could take more than 30 minutes to pass ¼-½ cc of rinsing fluid. This may not be sufficient to render the pump operational.
BRIEF SUMMARY OF THE INVENTION
According to an aspect of the invention, there is provided an apparatus for delivering a fluid. The apparatus includes a housing, an inlet in the housing for receiving the fluid, an outlet in the housing for discharging the fluid, a piston channel within the housing through which the fluid flows from the inlet to the outlet, and an actuator positioned within the housing and moveable between a retracted position and a forward position. The actuator in conjunction with the piston channel defines a piston chamber for storing fluid received through the inlet when the actuator is in the retracted position. The actuator drives the fluid stored in the piston chamber toward the outlet when the actuator transitions from the retracted (or refill) position to the forward (or delivery) position. The actuator includes an armature and a piston coupled to the armature and moveable within the piston channel. The piston has a groove in an outer surface for conducting fluid from the inlet to the outlet.
According to a further aspect of the invention, there is provided an actuator for delivering fluid through a piston channel from an inlet to an outlet. The actuator includes an armature configured to move between a forward position and a retracted position, and a piston that is coupled to the armature and moveable within the piston channel. The piston has a groove in an outer surface for conducting fluid through the groove.
According to a still further aspect of the invention, there is provided an actuator mechanism including an armature portion and a piston portion coupled to the armature portion and having a groove in an outer surface thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will hereinafter be described in conjunction with the following drawings wherein like reference numerals denote like elements throughout, and
FIG. 1 is an isometric view of an implantable infusion device in accordance with the prior art;
FIG. 2 is an isometric view of a drive mechanism for the implantable infusion device shown in FIG. 1 ;
FIG. 3 is a cross-sectional view of a drive mechanism in accordance with a first embodiment of the present invention;
FIG. 4 is an exploded view of an embodiment of the drive mechanism shown in FIG. 3 ;
FIG. 5 is an isometric view of an embodiment of an actuator including an armature and a grooved piston for use in the drive mechanism shown in FIGS. 3 and 4 ;
FIGS. 6 , 7 , and 8 are simplified cross-sectional views of the drive mechanism shown in FIG. 3 in quiescent, forward, and retracted states, respectively;
FIGS. 9 , 10 , and 11 are cross-sectional views of three piston grooves in accordance with an embodiment of the present invention;
FIG. 12 is a graph illustrating the relationship between pressure differential and volume pull-through for grooved and ungrooved actuator pistons;
FIG. 13 is a graph illustrating the relationship between stroke volume and pulse period for grooved and ungrooved actuator pistons;
FIG. 14 is an isometric view of a portion of an actuator piston having first and second oppositely directed helical grooves;
FIG. 15 is an isometric view of a portion of an actuator piston having a helical groove with very few turns; and
FIG. 16 is an isometric view of a portion of an actuator piston having a plurality of longitudinal straight grooves.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description is of the best presently contemplated mode of implementing the invention. This description is not to be taken in a limiting sense, but is merely for the purpose of illustrating the general principles of embodiments of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention. The scope of the invention is best defined by the appended claims.
As discussed above, embodiments of the present invention relate to an infusion device and to a drive mechanism including an actuator that improves fluid flow from the device's inlet reservoir to the device's outlet and facilitates the periodic cleaning of the device.
FIG. 1 shows an implantable infusion device 10 in accordance with the teachings of the prior art. The illustrated device 10 is configured to be surgically implanted into a patient, for example, in the abdominal region, between the skin and the abdominal wall. A catheter connected to the pump may deliver infusion medium to the patient, for example, by feeding infusion medium to a particular location in the venous system, within the spinal column, or in the peritoneal cavity of the patient. As described below, embodiments of the device 10 are configured in accordance with one or more aspects of the invention for enhancing prolonged usage and cleaning after implantation. However, further embodiments of the invention may be implemented as external infusion devices, which connect to patients through suitable catheter devices or the like. Yet further embodiments of the invention may be used in other contexts; e.g. for delivery of a medium into other suitable environments. Therefore, for purposes of simplifying the present disclosure, the term “patient” is used herein to refer to any environment in which an implantable device is implanted or to which an external device is connected, whether or not the implant or connection is carried out for medical purposes. Also, the term “infusion medium” is used herein to refer to any suitable medium delivered by the drive device.
The device 10 includes a generally disc-shaped housing 14 . While a generally circular disc-shaped embodiment is illustrated in FIG. 1 , it will be understood that further embodiments of the invention may employ housing of other shapes, including, but not limited to, oval, oblong, rectangular, or other curved or polygonal shapes. In implantable devices, the housing 14 is made of a biocompatible material and most often has a relatively small diameter and thickness to reduce patient trauma during implant surgery and after implantation.
The housing 14 includes a reservoir 16 for holding a volume of infusion medium, such as, but not limited to, a liquid medication to be administered to the patient. Housing 14 also contains a drive mechanism 18 (e.g. a pump), a power source 13 , and control electronics 20 described below. Pump 18 is configured to receive infusion media from reservoir 16 via a pump inlet 22 . Inlet structure 22 provides a closeable and sealable fluid flow path to the reservoir in the reservoir portion of the housing. The inlet structure includes a port for receiving a needle through which fluid may be transferred to the infusion device; for example, to fill or re-fill the reservoir of the device with the infusion media or a rinsing fluid as will be more fully discussed below. In particular embodiments, the inlet structure is configured to re-seal after a fill or re-fill operation, and to allow multiple re-fill and re-seal operations. One example of an inlet structure is described in U.S. Pat. No. 6,652,510, titled “Infusion Device and Reservoir for Same,” which is incorporated herein by reference. However, further embodiments may employ other suitable inlet structures, including, but not limited to, those described in U.S. Pat. Nos. 5,514,103 and 5,176,644, each to Srisathapat et al.; U.S. Pat. No. 5,167,633 to Mann et al.; U.S. Pat. No. 4,697,622 to Swift; and U.S. Pat. No. 4,573,994 to Fischell et al. Representative examples of reservoir housing portions and reservoirs which may be employed in embodiments of the invention are described in the above referred to U.S. Pat. No. 6,652,510, and further embodiments may employ other suitable reservoir configurations, including, but not limited to, those described in the above referred to U.S. Pat. Nos. 5,514,103; 5,176,644; 5,167,633; 4,697,622; and 4,573,994.
Returning now to FIGS. 1 and 2 , pump 18 has an outlet 24 through which the infusion medium may be expelled. When the device 10 is implanted in a patient or connected externally to a patient, a catheter 12 may be connected to the outlet 24 to deliver expelled infusion medium into the patient's blood stream or to a selected location in the patient's body.
The infusion device 10 includes a drive mechanism 18 such as a pump, and an electronic control system 20 located in the housing portion 14 . The drive mechanism 18 is connected between the reservoir and the outlet of the infusion device. The electronic control system 20 includes a power source 13 , such as a battery, and control electronics for controlling the drive mechanism 18 to deliver infusion medium from the reservoir to the patient in a prescribed manner. The drive mechanism may be controlled to deliver infusion medium in any suitable manner; for example, according to a programmed dispensing rate or schedule or according to an actuation signal from a sensor, timer or other suitable source.
In particular embodiments, both the drive mechanism 18 and the reservoir 16 are hermetically sealed. In such embodiments, the housing 14 containing drive mechanism 18 and control electronics 20 may be made from titanium or titanium alloy or other biocompatible metals, while the reservoir portion 16 of the housing may be made from such metals or a biocompatible and infusion medium compatible plastic as long as the material is such as to permit the required hermeticity.
The drive mechanism 18 includes mechanical and electromagnetic components that inhabit a volume of space within the housing 14 in which the components reside and operate. In that regard, the drive mechanism can contribute to the thickness requirements of the housing 14 , and thus to the overall thickness of the device 10 . The ability to reduce or minimize the device thickness without compromising the drive capabilities can provide significant advantages with respect to patient comfort, appearance and flexibility in selecting implant locations of the body. In particular embodiments, the drive mechanism 18 is configured to have a relatively small thickness thus allowing the device 10 to have a relative small thickness. Also in particular embodiments, the device 10 is configured such that, once implanted, it functions for a relatively long period of time to administer infusion medium to the patient to periodically be replenished from the outside of patient's body, and to be periodically rinsed to remove unwanted protein build-up on the fluid path surfaces that may degrade the performance of the infusion device.
FIG. 2 illustrates a drive mechanism 18 in accordance with the prior art. The drive mechanism 18 has a partially cylindrical, disc-shaped configuration having an inlet 30 and an outlet 24 . The inlet 30 may be coupled in fluid communication with reservoir 16 of device 10 ( FIG. 1 ) through a suitable conduit (not shown) within the device 10 . Similarly, the outlet 24 may be coupled in fluid communication with outlet 12 of the device 10 in FIG. 1 , through a suitable conduit (not shown) within the device 10 .
FIG. 3 is a cross-sectional view of a drive mechanism 18 in a retracted position or state in accordance with an embodiment of the present invention. As described in more detail below, the drive mechanism 18 employs electromagnetic and mechanical forces to change (or move) between retracted and forward states to cause infusion medium to be drawn in through the inlet 30 and forced out of the outlet 24 , respectively. The assembly of components shown in FIG. 3 is also shown in an exploded view in FIG. 4 .
Referring to FIGS. 3 and 4 , the drive mechanism 18 includes a housing member 32 that is open on one side to a hollow, annular interior section 34 . The housing 32 has a central hub portion 36 with a central piston channel 38 . The bottom side of the housing member 32 (with reference to the orientation shown in FIG. 3 ) includes an opening to the hollow interior section 34 through which coil wires may pass, as described below. The bottom side of the housing member also includes a configuration of recesses and cavities for providing an outlet chamber and an outlet passage. The housing member 32 is most often made of generally rigid, biocompatible and infusion medium compatible material having no or low magnetic permeability such as, but not limited to, titanium, stainless steel, bio-compatible plastic, ceramic, glass or the like.
As shown in FIGS. 3 and 4 , a coil cup 40 is located within the annular interior section 34 of the housing 32 . The coil cup 40 has a generally cylinder shape, open on one side to a hollow, annular interior. The coil cup 40 includes a bore 42 located in a central hub portion 44 and extending axially relative to the annular interior. The hub portion 44 of the cup member defines an inner annular wall 46 having an end surface 48 (or inner pole surface) having a width W 1 . The cup member 40 has an outer wall 50 having an end surface 52 (or outer pole surface) having a width W 2 . The outer wall 50 is connected to the inner wall 46 of hub portion 44 by a backiron portion 51 of the cup member 40 . As described in further detail below, at the open end of cup member 40 , the end surfaces 48 and 52 of the inner and outer walls 46 and 50 , respectively, define pole surfaces that cooperate with pole surfaces on an armature to provide a path for electromagnetic flux during a forward stroke of the drive mechanism. In particular embodiments, the width W 1 of inner pole surface 48 is greater than the width W 2 of the outer pole surface 52 to provide certain electromagnetic characteristics as described below.
When assembled, the coil cup 40 is located in the hollow interior of the housing member 32 , with the central portion 36 of the housing 32 extending through channel 42 of the coil cup 40 as shown in FIG. 3 . A coil 54 is located within the hollow, annular interior of the coil cup 40 and is disposed around the axis of the annular interior of the coil cup 40 . The coil cup 40 is provided with an opening 56 through which coil leads extend, as shown in FIGS. 3 and 4 . The coil cup 40 is most often made of generally rigid material having a relatively high magnetic permeability such as, but not limited to, low carbon steel, iron, nickel, ferritic stainless steel, ferrite, other ferrous materials, or the like. The coil 54 includes a conductive wire wound in a coil configuration. The coil wire may include any suitable conductive material such as, but not limited to, silver, copper, gold or the like, with each turn electrically insulated from adjacent turns and the housing. In one particular embodiment, the coil wire has a square or rectangular cross-section to achieve minimal space between windings and a greater number of coil turns thus improving electrical efficiency.
The drive mechanism 18 also includes an actuator member 58 , which has an armature portion 60 and a piston portion 62 . The actuator member is most often made of a generally rigid, biocompatible and infusion medium compatible material having a relatively high magnetic permeability such as, but not limited to, ferrous materials, ferritic stainless steel with high corrosion resistance, or the like. In the embodiment of FIGS. 3 , 4 , and 5 , the actuator (with an armature portion 60 and a piston portion 62 ) is formed as a single, unitary structure. In other embodiments as described below, the piston portion may be a separate structure with respect to the armature portion.
A perspective view of the example actuator member 58 is shown in FIG. 5 , where the armature portion 60 of the actuator member has a round, disc shape, and may be provided with at least one opening, and most often a plurality of openings as shown in the drawing. The openings in the illustrated example include a plurality of substantially circular openings 66 . The sections 68 of the armature 60 between openings 66 generally define radial struts coupling an annular outer section (or outer pole) 70 to an inner section (or inner pole) 72 of the armature. In particular embodiments, the width W 1 of the inner pole surface is greater than the width W 2 of the outer pole surface corresponding to the difference between the width of the pole surface 48 on the inner wall 46 of the cup member and the width of the pole surface 52 on the outer wall 50 of the cup member.
As described in more detail below, the armature 60 cooperates with the inner and outer walls of the coil cup 40 to provide a flux path for electromagnetic flux. The spacing between the pole surfaces on the armature 60 and the pole surfaces on the coil cup walls define gaps in the flux path. In particular embodiments, the spacing between the surface of outer pole 70 of the armature 60 and the surface of outer pole 52 of the outer wall 50 of the coil cup 40 (or a barrier 74 described below) is greater than the spacing between the surface of inner pole 72 of the armature and the pole surface 48 of the inner wall 46 of the coil cup (or the barrier 74 ) when the actuator is in the retracted position shown in FIG. 3 .
The radial struts 68 in the armature provide radial paths for electromagnetic flux between the outer and inner pole sections 70 and 72 of the armature. The openings 66 provide a passage for infusion medium to pass as the actuator 58 is moved between retracted and forward stroke positions to reduce resistance to the actuator motion that the infusion medium may otherwise produce. The configuration of openings is most often designed to provide a sufficient conductor for electromagnetic flux and yet minimize or reduce viscous resistance to actuator motion. With reference to FIG. 3 , the actuator member 58 is arranged with the piston portion 62 extending through the axial channel 38 of the housing 32 and with the armature portion 60 positioned adjacent to the open side of the coil cup 40 . An actuator spring 78 is positioned to force the armature portion 60 of the actuator 58 in the direction away from the open side of the coil cup 40 to provide a gap between the armature 60 and the open side of the coil cup 40 . A biocompatible and infusion medium compatible barrier 74 is located over the open side of the coil cup 40 between the armature 60 and the coil cup 40 to help seal the annular interior of the coil cup 40 and coil 54 . In other embodiments in which infusion medium may contact the coil, the barrier 74 may be omitted.
The actuator spring 78 in the illustrated embodiment includes a coil spring disposed around the piston portion 62 of the actuator 58 adjacent the armature portion 60 . One end of the coil spring abuts the armature portion 60 of the actuator, while the opposite end of the coil spring abuts a shoulder 81 in the piston channel 38 of the housing 32 . In this manner, the actuator spring 78 imparts a spring force between the housing and the actuator 58 to urge the actuator toward its retracted position shown in FIG. 3 .
In the illustrated embodiment, by using a coil spring 78 located around and coaxial with the piston portion 62 and disposed partially within the piston channel 38 , the actuator spring may have minimal or no contribution to the overall thickness dimension of the drive mechanism. However, in other embodiments, actuator springs may have other suitable forms and may be located in other positions suitable for urging the actuator toward its retracted position shown in FIG. 3 . The actuator spring 78 is most often made of a biocompatible and infusion medium compatible material that exhibits a suitable spring force such as, but not limited to, titanium, stainless steel, MP35N cobalt steel or the like.
The drive mechanism 18 further includes a cover member 80 which attaches to the housing member 32 over the open side of the housing member and the barrier 74 . The cover member 80 is most often made of a generally rigid, biocompatible and infusion medium compatible material having a relatively low magnetic permeability (being relatively magnetically opaque) such as, but not limited to, titanium, stainless steel, biocompatible plastic, ceramic, glass or the like.
The cover member 80 defines an interior volume 82 between the barrier 74 and the inner surface of the cover member. The armature portion 60 of the actuator member 58 resides within the interior volume 82 when the cover is attached to the housing below, the armature 60 is moveable in the axial direction within the volume 82 between a retracted position shown in FIG. 3 and a forward stroke position. This movement is created by the action of electromagnetic force generated when a current is passed through the coil 54 and the mechanical return action of the actuator spring 78 .
An adjusting plunger 84 is located within the cover 80 for contacting the armature 60 when the armature is in the fully retracted position shown in FIG. 3 to set the retracted position of the armature. In particular embodiments, a seal (e.g. a silicon rubber sealing ring) may be disposed between the plunger 84 and the cover member 80 . In further embodiments, a flexible diaphragm 85 (such as, but not limited to, a thin titanium sheet or foil) may be coupled to the inside surface of the cover 80 and sealed around the opening through which the plunger 84 extends. The diaphragm will flex to allow the plunger to define an adjustable retracted position and, yet, provide sealing functions for inhibiting leakage at the interface between the plunger 84 and the cover 80 . In other embodiments, after a proper armature position is set, the plunger is fixed in place with respect to the cover member, for example, by adhering the plunger to the cover member with one or more welds, adhesives or other securing methods.
The cover member 80 includes the inlet 30 of the drive mechanism, which has an inlet opening 86 in fluid flow communication with the interior volume 82 as described below. The inlet opening 86 connects in fluid flow communication with the reservoir of the infusion device 10 ( FIG. 1 ) to receive infusion medium from the reservoir. Connection of the inlet opening 86 and the reservoir may be through suitable conduit (not shown), such as tubing made of suitable infusion medium compatible material, including, but not limited to, titanium, stainless steel, biocompatible plastic, ceramic, glass or the like.
The inlet opening 86 provides a flow path to an inlet chamber 88 formed in the cover member 80 adjacent the inlet opening. A filter or screen member, such as a porous or screen material 90 , may be disposed within the inlet chamber 88 . The filter or screen member 90 is provided in a flow path between the inlet opening 86 and an inlet port 92 to the volume 82 . A one-way inlet valve (not shown) may also be provided in the flow path between the inlet opening 86 and the inlet port 92 or within the inlet port 92 to allow medium to flow into but not out of the interior volume 82 through the inlet. The cover member 82 may be provided with an inlet cover 94 that, when removed, allows access to the inlet chamber 88 to, for example, install, replace or service a filter 90 or inlet valve, or to service or clean the inlet 86 .
As shown in FIG. 3 , the piston portion 62 of the actuator 58 extends through the axial channel 38 in the housing 32 toward an outlet chamber 98 at the end of the axial channel 38 . The channel 38 has an inside diameter which is larger than the outside diameter of the piston portion 62 . As a result, an annular volume is defined between the piston portion 62 and the wall of the axial channel 38 along the length of the axial channel 38 . Infusion medium may flow through the annular volume 82 within the cover 80 to a piston chamber 100 located between the free end of the piston portion 62 and a valve member 102 of a valve assembly 96 . In particular embodiments, the radial spacing between the piston portion 62 and the wall of the channel 38 is selected to provide a suitable flow toward the piston chamber 100 to refill the piston chamber 100 (during a return stroke of the piston portion), but small enough to sufficiently inhibit back flow of medium from the piston chamber 100 (during a forward stroke of the piston portion).
The actual radial spacing between the piston portion 62 and the wall of the channel 38 to achieve such results depends, in part, on the overall dimensions of those components, the pressure differentials created in the mechanism, and the viscosity of the infusion medium. In particular embodiments, the radial spacing is selected such that the volume of medium for refilling is between about 1 and 4 orders of magnitude (and, most often, about 2 orders of magnitude) greater than the volume of medium that back-flows through the space. Alternatively, or in addition, the radial spacing may be defined by the ratio of the diameter D P of the piston portion 62 to the diameter D C of the channel 38 , where the ratio D P /D C is most often within a range of about 0.990 to about 0.995. As a representative example, a total spacing of about 400 to 600 micro-inches and, most often, an average radial gap of about 250 micro-inches annularly around the piston portion 62 may be employed.
The valve assembly 96 in the embodiment of FIG. 3 includes the valve member 102 and a valve spring 106 . The valve member 102 is located within the outlet chamber 98 and, as shown in FIG. 3 , is positioned to close the opening between the axial channel 38 and the outlet chamber 98 when the actuator 58 is in the retracted position. During the forward stroke, the valve member 102 is positioned to open a flow passage between the axial channel 38 and the outlet chamber 98 . The valve spring 106 is located within the outlet chamber 98 to support the valve member 102 . The spring 106 imparts a spring force on the valve member 102 in the direction toward piston 62 urging the valve member 102 toward a closed position to block the opening between the axial channel 38 and the outlet chamber 98 .
The valve member 102 is most often made of generally rigid, biocompatible and infusion medium compatible material, such as, but not limited to, titanium, stainless steel, biocompatible plastic, ceramic, glass, gold, platinum or the like. A layer of silicon rubber or other suitable material may be attached to the rigid valve member material on the surface facing the channel 38 to help seal the opening to channel 38 when the valve member is in the closed position shown in FIG. 3 .
The valve spring 106 is most often made of biocompatible and infusion medium compatible material that exhibits a suitable spring force such as, but not limited to, titanium, stainless steel, MP35N cobalt steel or the like. In the illustrated embodiment, the valve spring 106 is a coil spring. In other embodiments, other suitable valve spring configurations may be employed, including, but not limited to, helical, flat, radial, spiral, barrel, hourglass, constant or variable pitch springs or the like.
The embodiment shown in FIG. 3 utilizes a valve cover 110 sealed to the housing 32 to enclose the outlet chamber 98 . The valve cover 110 is most often made of a generally rigid, biocompatible and infusion medium compatible material, such as, but not limited to, titanium, stainless steel, biocompatible plastic, ceramic, glass, gold, platinum or the like.
The coil 54 may be inserted into the annular interior of the coil cup 40 with the coil leads extended through a coil lead opening 56 in the coil cup. The coil may be impregnated or partially impregnated with a fill material of epoxy or the like for adhering the coil to the coil cup and for sealing or partially sealing the coil. The fill material may also be used to adhere the barrier plate to the coil members to avoid warping or bulging of the barrier plate after assembly.
The coil cup 40 and the coil 54 may be inserted into the interior of the housing 32 with the coil leads (which may be wire leads or flexible conductive tabs) extending through a coil lead opening 56 in the housing 32 . In particular embodiments, the coil cup and housing are configured to provide a tight friction fit that does not require additional means to adhere the two components together. In other embodiments, the coil cup 40 and housing 32 may be coupled together by a suitable adhesive material or other adhering methods, including, but not limited to, welding, brazing or the like.
The barrier 74 may be placed over the coil, coil cup and housing sub-assembly. The barrier 74 may be adhered to the housing by one or more adhering points or continuously secured along the circumference of the barrier 74 with any suitable adhesive material or other adhering methods including, but not limited to, welding, brazing, soldering, or the like. Alternatively, or in addition, the barrier 74 may be held in place by a shoulder portion of the cover 80 , as shown in FIG. 3 . In addition, as noted above, the barrier 74 may be adhered to the coil 54 by fill material in the coil. In particular embodiments, the barrier 74 is held in a generally flat position relative to the coil cup and coil. To enhance this flat relationship, the coil cup and housing may be assembled together and then machined to planarize the barrier contact surfaces prior to inserting the coil in the coil cup and prior to adding fill material to the coil.
After the barrier 74 is placed over the coil, coil cup and housing, the actuator 58 may be added to the sub-assembly. First, however, the actuator spring 78 is placed around the piston portion 62 adjacent the armature portion 60 of the actuator. Then the free end of the piston portion 62 is passed through the axial channel 38 of the housing 32 with the armature end of the actuator arranged adjacent the barrier 74 .
The cover member 80 may then be disposed over the armature end of the actuator and secured to the housing 32 . In particular embodiments, the cover member 80 is adhered to the housing by one or more adhering points or continuously along the circumference of the cover member 80 with one or more welds or any other suitable adhering methods, including, but not limited to, adhesive materials, brazing or the like. The inlet filter 90 and the inlet cover 94 may be pre-assembled with the cover member 80 prior to adding the cover member to the sub-assembly. Alternatively, the filter 90 and the inlet cover 94 may be added to the cover member 80 after the cover member 80 is assembled onto the housing 32 . In particular embodiments, the filter 90 is disposed within the inlet chamber 88 and then the inlet cover 94 is adhered to the cover member 80 by one or more adhering points or continuously along the circumference of the inlet cover with one or more welds or any other suitable adhering methods, including, but not limited to, adhesive materials, brazing or the like.
The valve side of the drive mechanism may be assembled before or after the above-described components are assembled. On the valve side of the drive mechanism, the valve member 102 is disposed within the outlet chamber cavity 98 of the housing 32 adjacent the opening to the axial channel 38 . The valve spring 106 is then disposed within the outlet chamber cavity 98 adjacent the valve member 102 . The valve cover 110 may then be placed over the outlet chamber cavity 98 . In particular embodiments, the valve cover 110 is adhered to the housing 32 by one or more adhering points or continuously along the circumference of the valve cover with one or more welds or any other suitable adhering methods, including, but not limited to, adhesive materials, brazing or the like.
The volume of piston chamber 100 , the compression of the actuator spring 78 , and the position of the actuator 58 in the retracted position shown in FIG. 3 may be adjusted by adjusting the position of the adjusting plunger 84 . In one particular embodiment, the adjusting plunger includes a threaded cylindrical member that engages corresponding threads in a plunger aperture in the cover member 80 to allow adjustment in a screw-threading manner. The diaphragm 85 under the plunger 84 contacts the armature portion 60 of the actuator inside of the cover member 80 . The other end of the plunger 84 may be provided with a tool-engagement depression for allowing engagement by a tool, such as a screw-driver, Allen wrench or the like, from outside of the cover member 80 . By engaging and rotating the plunger 84 with a suitable tool, the depth that the plunger extends into the cover member 80 may be adjusted to adjust the retracted position of the armature portion 60 relative to the barrier 74 (to adjust the gaps between the pole sections 70 and 72 of the armature and pole sections formed by the coil cup 40 when the actuator is in the retracted position of FIG. 3 ). In one particular embodiment, adjustments of the plunger 84 are made during manufacture. In that embodiment, the adjusted position is determined and set by welding or otherwise adhering the plunger 84 in the adjusted position during the manufacture. In other embodiments, the plunger 84 is not set and welded during manufacture to allow adjustment of plunger 84 after manufacture.
FIGS. 6 , 7 and 8 are simplified cross-sectional views of the drive mechanism 18 shown in FIG. 3 and will be useful in explaining the operation of drive mechanism 18 . In the interest of clarity, only major functional features and components are illustrated, and these are identified by reference numerals corresponding to reference numerals used in FIG. 3 to denote like features and components.
FIG. 6 illustrates drive mechanism 18 in its quiescent state. That is, valve member 102 is fully extended under the force of spring 106 , piston chamber 100 and inlet chamber 88 are substantially filled with infusion media (or rinsing media as the case may be), and coil 54 is de-activated (not energized or inadequately energized) in a manner to overcome the force of spring 78 . Drive mechanism 18 employs electromagnetic and mechanical forces to move between retracted ( FIG. 8 ) and forward ( FIG. 7 ) positions to cause infusion medium to be drawn into and driven out of the mechanism in a controlled manner. In the retracted position, the spring 78 urges the actuator 58 toward its retracted position shown in FIG. 8 . When the coil 54 is energized to overcome the spring force of spring 78 , the actuator 58 moves to its forward stroke position shown in FIG. 7 . The movement of the actuator between retracted and forward positions creates pressure differentials within the internal chambers and volumes of the drive mechanism 18 to draw medium into the inlet 86 and drive medium out the outlet 24 .
More specifically, when the coil 54 is de-activated, the actuator 58 is held in its retracted position ( FIGS. 6 and 8 ) under the force of the spring 78 . When coil is de-activated immediately following a forward stroke, the spring 78 moves the actuator 58 to the retracted position of FIG. 8 from the forward position shown in FIG. 7 . The openings 66 ( FIG. 5 ) in the armature portion 60 of the actuator 58 provide passages for medium to pass and, thus, reduce viscous drag on the actuator. As a result, the actuator 58 may move to its retracted position ( FIG. 8 ) relatively quickly.
As the actuator 58 retracts, the piston portion 62 of the actuator is retracted relative to the valve member 102 such that a piston chamber 100 volume is formed between the end of the piston portion 62 and the valve member 102 . The formation of the piston chamber 100 volume creates a negative pressure which draws infusion medium (or rinsing fluid) from the volume 82 of the cover member 80 through the annular space between the piston portion 62 and the wall of the channel 38 and into the piston chamber 100 as is indicated by arrows 120 . While not shown, one or more channels could be provided through the piston portion 62 to provide one or more additional flow paths to the piston chamber 100 if desired.
In the retracted position, a gap is formed between each of the annular pole surfaces 48 and 52 defined by the inner and outer walls 46 and 50 of the coil cup 40 and respective annular surfaces of the inner and outer pole sections 72 and 70 of the actuator's armature portion 60 . With particular reference to FIG. 3 , a first gap is formed between the annular pole surface 48 of the inner cup member wall 46 and the annular surface of the inner pole section 72 . A second gap is formed between the annular surface 52 of the outer cup member wall 50 and the annular surface of the outer pole section 70 .
When the coil 54 is energized in a manner to overcome spring force 78 , the actuator 58 is forced in the direction to close the gaps and moves to its forward position ( FIG. 7 ) under the influence of electromagnetic flux generated by the energized coil. In particular, the coil may be energized by passing an electrical current through the coil conductor to create electromagnetic flux. The electromagnetic flux defines a flux path through the coil cup walls across the gaps and through the armature portion of the actuator. The electromagnetic flux provides an attraction force between the annular surfaces 48 and 52 of the coil cup 40 and the annular surfaces of the armature's pole sections 70 and 72 to overcome the spring force of spring 78 and draw the armature 60 toward the coil cup.
As the armature portion 60 of the actuator is drawn toward the coil cup 40 , the piston portion 62 of the actuator is moved axially through the channel 38 in the direction toward the outlet chamber 98 . With the coil energized, the piston portion 62 continues to move under the action of the armature until a mechanical stop is reached, for example, mechanical contact of the actuator 58 with the barrier 74 , a portion of the housing 32 or cover member 80 . In other embodiments, the motion may continue until the return force of the spring and fluid pressure overcomes the electromagnetic force provided by energizing the coil.
The movement of the piston portion 62 towards the stopping point reduces the volume of the piston chamber 100 and increases the pressure within the piston chamber until the pressure is sufficient to overcome the force of the valve spring 106 . As the valve spring force is overcome by the pressure within the piston chamber, the valve member 102 is moved toward an open position, away from the opening between the piston chamber 100 outlet chamber 98 . When the valve member 102 is in the open position, medium is discharged through the outlet chamber 98 and outlet 24 as is indicated by arrow 128 in FIG. 7 .
When the coil is deactivated and the piston portion 62 is moved back to its retracted position, the pressure in the piston chamber 100 reduces and the valve member 102 is reseated under the action of the valve spring 106 . This prevents fluid from flowing back into the drive mechanism through the outlet. In addition, a negative pressure is created in the piston chamber 100 to draw medium into the chamber for the next forward stroke, as described above.
In this manner, energization of the coil 54 to move the actuator 58 to its forward position ( FIG. 7 ) causes a measured volume of medium to be discharged from the outlet. As described above, when the coil 54 is de-energized, the actuator 58 is returned to the retracted position ( FIG. 8 ) under the force of spring 106 and an additional volume of medium is drawn into the piston chamber 100 for the next discharging operation. Accordingly, the coil 54 may be energized and de-energized by a controlled electronic pulse signal where each pulse may actuate the drive mechanism 100 to discharge a measured volume of medium. In particular embodiments, the coil 54 may be electrically coupled to an electronic control circuit (not shown) to receive an electronic pulse signal from the control circuit; for example, in response to a sensor signal, timer signal or other control signal input to the control circuit.
In particular embodiments, when the piston motion is stopped at the end of the forward stroke, the valve-facing end of the piston portion 62 is in close proximity to the valve member 102 , for example, spaced from the valve member 102 by a distance that is no more than two to three percent (2-3%) of the piston diameter. In further embodiments, the valve facing end of the piston portion 62 is in contact with the valve member 102 at the end of the forward stroke. In this manner, gas that may be present in the infusion medium is less likely to accumulate within the piston chamber 100 . More specifically, in some operational contexts, infusion medium may contain gas in the form of small bubbles that may migrate into the piston chamber 100 during filling of the piston chamber. As gas is significantly more compressible than liquid, too much gas within the piston chamber may adversely affect the ability of the drive mechanism to self prime.
In yet another embodiment, the piston portion 62 may contact the valve member 102 at the end of the forward stroke and push the valve member 102 open. In this embodiment, it is less likely that gas will be trapped between the piston portion 62 and the valve member 102 and more likely that the chamber will be purged of gas.
As already described, protein drugs such as insulin denature resulting in the deposition of denatured protein on the surfaces of the fluid delivery path. Over time, such deposits may (1) occlude the delivery path to the therapy site; (2) reduce clearances between moving parts and thus slow operation and perhaps ultimately cause jamming; (3) compromise the condition of valve mating surfaces causing the valve not to seat properly; and (4) create areas of precipitant coagulation that may grow and collect debris thus further impacting fluid flow and device operation.
These deposits may be periodically removed (e.g. once per year) by rinsing the implanted pump with a solvent (e.g. sodium hydroxide) to dissolve the deposits. The infusion device's reservoir is first filled with a desired buffer or rinsing solution. Since the device is implanted near the patient's skin, the reservoir may be filled utilizing a first syringe. A second syringe engages the device's outlet to produce a negative pressure differential and therefore help pull the fluid through the pump. The pump itself may be operated during this procedure to assist fluid flow through the pump. It is an established goal that the rinsing procedure should result in the transport of at least 1 cc of rinsing fluid from the inlet reservoir to the pump's outlet in approximately ten minutes. Rinse cycles less than ten minutes in duration may result in failure to dissolve all deposits, and rinse cycles greater than ten minutes may result in undue discomfort to the patient. The rinse procedure may include a multi-stage operation that involves emptying and refilling the pump's reservoir several times with different fluids, and different drugs may require the use of different rinsing agents. However, other time periods may be used depending on the agent used, the frequency between rinsings, the amount of deposits and/or the like.
As previously stated, the space or annulus between the actuator piston and the piston cylinder is approximately 150-200 micro-inches radially, a fairly tight fit, and it takes approximately 1 to 2 seconds to refill the piston chamber via the annulus. Deposits on the annulus walls, however, will restrict fluid flow thus increasing the time to refill the piston chamber, which, in turn, lowers the stroking frequency and causes the corrective rinse procedure to be protracted; e.g. it could take 30 minutes or so instead of the desired 10 minutes. The deposit build-up could be so severe so as to cause the pump to jam. In this case, it could take more than 30 minutes to pass ¼-½ cc of rinsing fluid and thus may not be sufficient to render the pump operational.
To overcome these problems and provide a more effective flow path for the rinsing agent, a groove is provided in the outer surface of the actuator piston. For example, actuator piston 62 is provided with a helical groove 64 and is shown in FIGS. 3 and 5 . Groove 64 may have, for example, a hemispherical cross-section as shown in FIG. 9 of sufficient cross-sectional area to ensure that a flow path will always exist regardless of the amount of deposits in the bore from the inlet end 130 of actuator piston 62 to the outlet end 132 of actuator piston 62 . In addition, the helical groove 64 is most often configured to deliver rinsing agent in close proximity to any protein deposit in the annulus between the actuator piston 62 and the surface of the central piston channel 38 . In this manner, rinsing agent can be effectively applied to deposits even when the actuator is jammed.
In particular, groove 64 is configured to conduct rinsing agent to within approximately 0.015 inch of any deposit in the annulus. To this end, it has been found that for devices of this nature, a groove having a depth that is approximately 1.5-6% of the diameter of the piston, a width that is approximately 3-30% of the diameter of the piston, a pitch that is approximately 8-70% of the diameter of the piston, and/or a cross-sectional area that is approximately 0.2-0.6% of the area of the piston face is helpful. More specifically, a groove having a width of substantially 0.012 inch, a depth of substantially 0.0035 inch, and a pitch of about 0.025-0.035 inch works quite well. In this case, the groove 64 will have approximately seven turns. More specifically, the groove may have 1-2 turns in the area occupied by piston spring 78 and 5-6 turns in the remainder of the piston 62 . It will be appreciated that a tight spiral path (i.e. many turns) makes it more certain that the rinsing agent will reach deposits in the annulus; however, too many turns could result in back leakage during the pumping stroke due to the corresponding reduction in the piston's regions of higher diameter which are responsible for the piston's tight fit within the piston channel. It is to be noted, however, that since the forward stroke is very fast (e.g. 1.5 milliseconds) and the refill time is much longer (e.g. 100-150 times longer), the back leakage is dramatically smaller than the forward flow. Furthermore, a helical groove of the type shown in FIG. 5 causes fluid flow to transition from laminar to turbulent thereby restricting fluid flow. Thus, the groove generally provides a flow path when the actuator is moving relatively slowly (retracting) and provides a sealing action when the actuator is moving fast (pumping).
While the groove in the outer surface of the actuator piston is shown in FIG. 9 as having a hemispherical cross-section, it is known that sharp edges in the flow path (such as edges 134 in FIG. 9 ) may cause further denaturing of the protein therapy drug. Therefore, in a particular embodiment shown in FIG. 10 , groove 64 has a cross-sectional shape including rounded edges 136 . It should be clear, however, that grooves having a variety of cross-sectional shapes may be employed depending on the particular application and circumstances, and all such grooves are considered to be within the scope of the present invention. For example, groove 64 shown in FIG. 11 includes rounded edges for the reasons described above, but has a cross-section that is generally more conical.
Groove 64 enhances the operation of drive mechanism 18 in several ways. First, it can assure that a flow path will exist between the pump's inlet 86 and outlet 24 even if there are heavy protein deposits on the surfaces of the flow path. This permits rinsing agent to pass through the mechanism even if the mechanism is jammed. Second, it can significantly shorten the refill period by 75 percent or more compared to that of a smooth, ungrooved actuator of similar dimensions thus increasing the amount of rinsing agent that may be pumped by the actuator. Under normal operation, the increased frequency of operation permits infusion rates to be increased thus permitting therapy drugs to be delivered to the patient more expeditiously.
The graph shown in FIG. 12 illustrates the relationship between the inlet-to-outlet pressure differential (horizontal axis) and the volume of fluid pulled through a pump in ten minutes (vertical axis) for a drive mechanism having a smooth actuator (curve 140 ) and an actuator including a seven-turn helical groove having a width of approximately 0.01 inch and a depth of 0.004 inch in the surface thereof (curve 142 ). As can be seen, at pressure differentials greater than −8 psig, the volume pull-through in the grooved actuator increases dramatically above that of the smooth actuator. In fact, at a differential pressure of −13 psig, the pull-through of the grooved actuator is over two times that of the ungrooved actuator. If the pump is operated while the differential pressure is applied, the volume passed through the pump will exceed 1 cc in 10 minutes.
FIG. 13 illustrates the relationship between stroke refill volume (vertical axis) and pump pulse period (horizontal axis) for a standard ungrooved actuator (curve 144 ), an actuator having a 0.0025 inch deep helical groove in its surface (curve 146 ), and an actuator having a 0.004 inch deep helical groove therein (curve 148 ). As can be seen, the stroke refill volume for the ungrooved actuator peaks at about 1.0 second, and the actuator with the 0.0025 inch deep helical groove therein peaks at about 0.6 second. The actuator having the 0.004 inch deep helical groove therein has a stroke refill volume that peaks in about 0.2 second, approximately five times faster than the ungrooved actuator piston. Thus, an infusion pump equipped with the grooved actuator piston characterized by curve 148 in FIG. 13 can be operated at approximately five times the speed of a pump having an ungrooved actuator piston.
Thus far, the inventive drive mechanism/actuator has been described in accordance with particular embodiments; i.e. one in which the actuator piston has a helical groove in the surface thereof. It should be appreciated, however, that different configurations and/or numbers of grooves may be utilized. For example, FIG. 14 illustrates an actuator piston 62 that includes a double helical groove formed by a right-spiral groove 150 and a left-spiral groove 152 . The use of two or more grooves such as is shown in FIG. 14 may permit the grooves to be shallower and still provide the desired results. FIG. 15 illustrates a helical groove 154 including a lesser number of turns, perhaps less than one turn, and FIG. 16 illustrates an actuator piston 62 having one or more straight grooves 156 in its surface. While reducing the number turns or utilizing straight grooves may result in increased back leakage during the forward stroke of the piston, the forward stroke (pumping) of the piston will still be substantially faster than the rearward stroke (refill) and the back leakage will still be substantially less that the forward flow. Finally, one or more such grooves may be provided in the cylinder wall to facilitate fluid flow as described above in connection with the groove or grooves in the armature piston.
Thus, there has been provided an infusion pump that dispenses predetermined dosages of a protein drug (e.g. insulin) and is configured to facilitate the passage of rinsing fluid to remove undesirable protein building on the fluid path surfaces. The infusion pump includes a piston pumping mechanism that includes an actuator configured to dissolve protein build-up on the surfaces of the piston and piston walls. In addition, the drive mechanism is configured to reduce the time it takes to refill the outlet chamber of the infusion pump to an acceptable time despite the build-up of protein deposits on the walls of the pump's fluid path.
While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing exemplary embodiments of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents. | An apparatus for delivering a fluid includes a housing, an inlet in the housing for receiving the fluid, and an outlet in the housing for discharging the fluid. A piston channel is provided within the housing through which the fluid flows from the inlet to the outlet. An actuator is positioned within the housing and is moveable between a retracted position and a forward position, the actuator defining a piston chamber for storing fluid received through the inlet when the actuator is in the retracted position and for driving the fluid stored in the piston chamber toward the outlet when the actuator transitions from the retracted position to the forward position. The actuator includes an armature and a piston coupled to the armature and moveable within the piston channel. The piston is provided with a groove in an outer surface for conducting fluid from the inlet to the outlet. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a dyeing apparatus and method for coloring articles such as garments or other textile products and particularly relates to batch dyeing processes.
2. Description Of The Prior Art And Objectives Of The Invention
Various techniques have been practiced in the textile industry for coloring or discoloring yarns, fabrics and garments including many continuous and batch dyeing techniques. In recent years, the fashion industry has promoted "worn" or faded styles whereby denim products are bleached and are "stone washed" to provide the fabric with an "aged or used" appearance. Style-conscious consumers are always looking for unique-appearing garments and as the current fashion trends provide a myriad of garment selections, the present invention was conceived and one of the objectives of the invention is to provide wearing apparel having a new, decorative mottled appearance.
It is another objective of the present invention to provide dyeing apparatus which will color garments such as socks or the like in a random, mottled manner in a fast, efficient process.
It is yet another objective of the present invention to provide dyeing apparatus which includes a rotatable container having a conduit attached thereto for supplying colorants or discolorants in an intermittent, periodic fashion.
It is also an objective of the present invention to provide products formed by the process with a unique, distinctive appearance which would be readily acceptable by the fashion-conscious consumers.
Other objectives and advantages of the present invention will become apparent to those skilled in the art as a more detailed description is presented below.
SUMMARY OF THE INVENTION
The aforesaid and other objectives of the invention are realized by providing dyeing apparatus having a rotatable container with baffles therein which will tumble the contents such as textile articles during rotation. A fluid conduit extends into the rotatable container which is provided with one or more outlets or apertures. A colorant source is connected to the conduit whereby, upon rotation of the container, liquid dye or colorants can be directed through the conduit and intermittently enter the container during rotation thereof to impinge the articles contained therein. The articles thus colored have an irregular dye pattern thereon and one or more colors can be introduced into the rotatable container either by adding additional conduits thereto or by allowing different colorants or discolorants to sequentially pass through a single conduit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 demonstrates dyeing apparatus of the present invention;
FIG. 2 illustrates an enlarged view of a section of the inside of the container of the dyeing apparatus of FIG. 1 with socks being processed therein;
FIG. 3 depicts a sock which has undergone the intermittent dyeing process; and
FIG. 4 shows a partial inside view of another embodiment of the rotatable container.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred form of the apparatus of the invention consists of a rotatable container which is driven by an electric motor and heated by a gas burner. Attached to the rotatable container or rotation therearound is a fluid conduit whereby a desired substance such as a dye, bleach or other colorants or discolorants can be intermittently delivered into the container as it rotates. Attached to the fluid conduit is a dye source such as a dye tank and a pump is provided for directing the colorant fluids along the conduit and into the rotatable container.
The preferred method of the invention consists of placing textile articles into the container and rotating the container around its horizontal axis. During rotation, a heated liquid colorant is delivered into a fixed conduit and openings therealong allow the colorant to periodically drip onto the garments during rotation and tumbling. After the dyeing process has sufficiently proceeded, the colorant supply is terminated and the articles are removed therefrom and conventional finishing techniques are applied.
The preferred form of the product of the process consists of wearing apparel which can be identified by its mottled, irregularly colored appearance.
DETAILED DESCRIPTION OF THE DRAWINGS AND OPERATION OF THE INVENTION
Turning now to the drawings, dyeing apparatus 10 as shown in FIG. 1 includes a rotatable drum or container 11 having a series of baffles 12 which tumble articles placed therein to provide a thorough mixing and blending action. Fluid conduit 13 consists of a pipe or tube with a series of apertures 14 therealong. Apertures 14 allow for the intermittent delivery such as by dripping of a heated (110° F.) colorant such as a cold reactive dye solution as, for example, a Procion™ dye as manufactured by ICI Americas, or a discolorant such as a bleach into rotatable container 11 onto socks 15 which may be cotton plaited nylon (50/50) as conventionally made although 100% natural or synthetic yarns or other various blends thereof are anticipated to be processed as herein described. Thus, as container 11 is rotated articles such as socks 15 are intermittently and randomly impinged with the desired coloring substance. As would be understood, various types of articles can be processed within apparatus 10 whether they be piece goods, garments, yarns or other products.
As further seen in FIG. 1, conduit 13 is attached to container 11 but remains stationary and container 11 rotates therearound. In FIG. 1 only one (1) conduit is shown although a plurality of conduits may be employed as required. In certain circumstances articles within container 11 may be tossed upon conduit 13 and to prevent or remedy this occurrence, sweep arms 50 as seen in FIG. 4 are provided. Sweep arms 50 parallel conduit 13 and rotate therearound as they are affixed to the rotatable end walls 51 of container 11. During rotation, arms 50 brush off any articles that may have fallen on conduit 13 during rotation or tumbling.
Dye source 16 as shown in FIG. 1 consists of dye tanks 32, 33 and 34 which feed into manifold 17 which is joined to pump 18. Pump 18 forces liquid along conduit 13 from one or more of tanks 32, 33 or 34 as required. Pump 18 consists of an adjustable metering pump of conventional design and sized to adequately supply the colorant requirements. Tanks 32, 33 and 34 may have jacket or other heaters as needed. Conduit 13 can be gravity fed or may be pump fed as shown in FIG. 1 depending on the particular requirements of the user. Apparatus 10 includes electric motor 19 and motor transmission 20 which consists of a gear reduction mechanism and drive means 21 which comprises a roller for turning container 11 and which is connected to transmission 20. Gas burner 22 and centrifugal fan 23 supply heat to container 11. Exhaust stack 24 allows the combustion components to be expelled outside into the atmosphere. Other types of heating systems such as heat exchangers employing steam can be used as practical and to obtain the heat ranges needed. For example, on 100% nylon articles certain acid dyes may require a temperature of approximately 200° F. to properly fix the dye.
The method of operation of apparatus 10 comprises opening door 25 for the loading of socks 15 or other articles. Once inside container 11 has been sufficiently loaded, motor 19 is activated by switch 26 on control panel 27 and the rotation of container 11 begins. The articles therein are tumbled and valve 28 can then be opened and pump 18 turned on to force the desired dyeing substance which may be a liquid dye at a slow rate through conduit 13. Conduit 13 then allows the liquid from dye tank 34 to slowly drip onto the articles contained therein to provide a mottled, randomly colored appearance. Once sufficient dye has been supplied, valve 28 can be turned off and valve 29 opened as tank 33 may contain a different colorant or discolorant such as a bleach and in sequential fashion thereafter, valve 29 can be closed and valve 30 opened and another colorant such as a dye or bleach from tank 32 is supplied. Once articles 15 are sufficiently impinged with the colorant, pump 18 is turned off and container 11 can then be heated by burner 22 or motor 19 can be turned off and articles 15 removed and conventional finishing processes employed. As would be understood, apparatus 10 and the methods as shown herein are simplified versions and automatic or microprocessor controls can be utilized in place of manual controls for greater production requirements and where automation and high speeds are justified to reduce cost and overhead expenses.
Sock 15 as shown in FIG. 3 demonstrates only one product formed by the process of the invention wherein socks are first knitted by conventional means with a white bleached cotton yarn plaited over a whitened nylon yarn and therefore after dyeing form a garment having a substantially white background 40. By dripping two (2) colors of dye, red and blue, sock 15 has areas 41 which are substantially red in appearance, areas 42 substantially blue and areas 43 substantially purple since areas 43 demonstrate the mixing of red and blue dyes thereon. Various rates of colorant delivery, rotational speed of container 11 and other variables contribute to the ultimate appearance of a particular article colored in this manner.
Various changes and modifications can be made to the invention by those skilled in the art without departing from its intended scope and the illustrations and examples provided herein are for explanatory purposes and are not intended to limit the appended claims. | A dyeing apparatus and method is presented whereby garments such as socks and other articles can be dyed to provide a mottled, random coloration thereon. The apparatus consists of a rotating container into which colorants or discolorants are dripped as the articles therein are tumbled. Garments can be colored with one or more substances to provide a wide variety in styles and patterns. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is based on and claims priority to U.S. Provisional Application Ser. No. 61/174,005, filed Apr. 30, 2009.
BACKGROUND
In a variety of subsea well related applications, subsea test trees (SSTTs) are installed within subsea risers during completion operations. The subsea test trees enable the safe and temporary closure of subsea wells. Depending on the application, a control system is positioned either at a topside location or a subsea location and coupled to the subsea test tree. The control system is used to actuate valves in the subsea test tree by controlling the delivery of hydraulic fluid through a control line. The hydraulic fluid is selectively applied to cause a desired change in state, e.g. transition of a valve, on the subsea test tree. In some of these applications, it may be desirable to design the control system with simplicity to obtain a desired Safety Integrity Level (SIL) rating recognized by the industry. However, designing the control system with simplicity for certification as an SIL unit can limit the ability to monitor functionality of the control system.
SUMMARY
In general, the present application provides a system and methodology for controlling a subsea test tree via a control system of a type suitable for gaining desired industry ratings. A monitoring system is utilized to monitor functions of the control system, but the monitoring system is independent from the control system.
BRIEF DESCRIPTION OF THE DRAWINGS
Certain embodiments will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 is a schematic view of a well system used in a subsea application, according to an embodiment;
FIG. 2 is a schematic illustration of one example of a control system and an independent monitoring system positioned to monitor functions of the control system, according to an embodiment;
FIG. 3 is a schematic illustration of subsea components of the control system and the monitoring system illustrated in FIG. 2 , according to an embodiment;
FIG. 4 is an orthogonal view of one example of a riser instrumentation module that can be utilized in the monitoring system, according to an embodiment;
FIG. 5 is another view of the riser instrumentation module illustrated in FIG. 4 , according to an embodiment; and
FIG. 6 is a schematic illustration of a gauge monitor pressure sensing arrangement, according to an embodiment.
DETAILED DESCRIPTION
In the following description, numerous details are set forth to provide an understanding of various embodiments. However, it will be understood by those of ordinary skill in the art that many embodiments may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
The present application generally relates to a technique for utilizing subsea control devices in subsea applications. This technique also relates to instrumentation that involves sensors and/or monitoring in subsea control devices and applications. The subsea systems and methodologies can be employed in a variety of subsea applications with wells formed in many types of subsea environments. For example, wells may be formed as generally vertical wells or as deviated, e.g. horizontal, wells, and the equipment used in a given well application may be selected according to the type of well, subsea environment, surface equipment, and other factors that affect the specific well application.
According to one embodiment, a subsea well 20 extends below a subsea test tree 22 positioned at a subsea location 24 along, for example, a seabed 26 , as illustrated in FIG. 1 . The subsea test tree 22 comprises a valve system 28 that may be selectively operated to open and shut off the subsea well 20 . In the example illustrated, subsea test tree 22 is connected with a surface structure 30 via a riser 32 or other suitable structure that provides a passage through the sea between surface structure 30 and subsea test tree 22 . The surface structure 30 may be at a surface location 33 and may be in the form of a surface vessel, a permanent structure or a semi-permanent structure depending on the type and location of subsea well 20 .
In the embodiment illustrated, a control and monitoring system 34 is employed in cooperation with the subsea test tree 22 . In this example, system 34 comprises a control system 36 operatively coupled with the subsea test tree 22 to control features of the subsea test tree, such as valve system 28 . System 34 further comprises a monitoring system 38 which is positioned and employed to monitor functions of control system 36 . In this example, monitoring system 38 comprises a riser instrumentation module system which is independent from and remains isolated from control system 36 .
Control system 36 may be constructed in a variety of configurations with various components depending on the specific application. However, one specific example of a type of control system for controlling subsurface test trees is a subsea test tree control system available from Schlumberger Corporation and known as SenTURIAN. As noted previously, however, this type of control system employs limited or no monitoring to ensure sufficient simplicity for certification as a Safety Integrity Level (SIL) unit having a desired SIL rating, e.g. a SIL 2 rating. The SenTURIAN control system and similar systems may be defined as Safety Instrumented Systems (SAS) per IEC Standard 61508. In the present system, however, addition of the independent riser instrumentation module system 38 enables the overall system 34 to monitor functions of the primary control system 36 while maintaining isolation from the SIL system, i.e. control system 36 . This allows the control system to be designed in a manner that maintains the desired SIL certification and promotes compliance with the applicable International Organization for Standardization (ISO) standards.
To maintain the desired SIL rating on control system 36 while adding monitoring capabilities, the control functions are isolated from the monitoring functions. To accomplish the isolation, the riser instrumentation module system 38 contains separate components, such as separate acquisition circuits, modem, communication lines, e.g. cable, and/or other independent components.
As discussed in greater detail below, monitoring system information may be communicated between the subsea location 24 and the surface structure 30 via a separate communication line 40 , e.g. cable, relative to a communication line 42 of control system 36 . By way of example, communication line 42 may comprise a plurality of hydraulic lines used to deliver fluid for actuating valve system 28 and/or other systems of subsea test tree 22 . Creation of independent monitoring and control systems means that any problem with the monitoring system 38 causes no effect on the ability of control system 36 to effectively carry out its safety functions with respect to actuation of valve system 28 and/or other systems of subsea test tree 22 .
Referring generally to FIG. 2 , the relationship between control system 36 and riser instrumentation module system 38 is illustrated. In this embodiment, control system 36 comprises a subsea control module 44 and a topside control system 46 that are connected with each other via communication line 42 . By way of example, communication line 42 may comprise a multicore cable having one or more hydraulic control lines. In this example, the monitoring system 38 comprises a subsea monitoring module 48 and a topside monitoring system 50 that are connected with each other via communication line 40 . By way of example, communication line 40 may comprise one or more electric, fiber-optic, wireless, or other suitable signal communication lines able to convey signals between the subsea location 24 and the surface location 33 . The subsea monitoring module 48 is designed to measure and monitor desired parameters, such as temperature and pressure in hydraulic control lines used to manipulate valve system 28 and/or other systems of subsea test tree 22 .
Communication line 40 and monitoring communication line 42 may be routed as two completely separated cables, or the communication lines 40 , 42 may be combined in a common umbilical 52 . If a common umbilical 52 is utilized, the communication lines 40 , 42 , e.g. cables, are maintained as independent paths for communicating signals between the subsea and surface locations. Accordingly, the isolated communication layout of the overall system is maintained. Additionally, data can be observed and/or input to control system 36 and/or monitoring system 38 via a display system 54 . By way of example, display system 54 may utilize a graphical user interface 56 for displaying information to a user and for allowing the user to input control commands or other system data.
As illustrated in FIG. 3 , parameters of control system 36 are monitored with appropriate sensors 58 of subsea monitoring module 48 . The sensors 58 may comprise, for example, a temperature sensor and/or pressure sensor associated with individual hydraulic lines 60 extending between subsea control module 44 and controlled components of subsea test tree 22 , e.g. valve system 28 . In some applications, other sensors, e.g. vibration sensors, also may be employed to detect parameters related to operation of control system 36 .
The sensors 58 may be associated with individual hydraulic lines or with a plurality of hydraulic lines, and the output from sensors 58 is directed to acquisition circuitry 62 that is completely independent of componentry of control system 36 . Acquisition circuitry 62 may be part of subsea monitoring module 48 or may be positioned at other suitable locations in monitoring system 38 . In the particular example illustrated, parameter data is directed to one or more sensors 58 by providing a “T” in the corresponding hydraulic line 60 to measure, for example, pressure and temperature of the hydraulic control line 60 without obstructing its function. Use of the “T” coupling enables observation of the desired parameter at a specific location 63 along the hydraulic line; however other systems may be used to observe the desired parameter.
Subsea monitoring module 48 may be constructed in various configurations with components selected to enable independent monitoring of control system functions. In one example illustrated in FIG. 4 , the subsea monitoring module comprises a modular monitoring hub 64 that may be mounted at a variety of locations along the subsea test tree 22 and riser 32 to monitor a desired parameter or parameters related to control system 36 . For example, the modular monitoring hub 64 may be constructed as a pressure and/or temperature monitoring hub utilized in cooperation with the control system 36 to monitor pressure/temperature in control lines at the desired location. The modular monitoring hub 64 may be mounted on a mandrel 66 , such as a 10 ksi or 15 ksi mandrel of the type used in a variety of offshore, well related applications.
In one example, modular monitoring hub 64 is designed to slide over and attach to mandrel 66 , as illustrated in FIG. 4 . As further illustrated in FIG. 5 , the modular monitoring hub 64 may comprise a plurality of hydraulic flow ports 68 designed to enable measuring and monitoring of the desired parameter at specific locations 63 along subsea test tree 22 and/or riser 32 . In this manner, monitoring hub 64 can be designed as a modular component for utilization in many types of riser systems to monitor hydraulic lines or other pressure lines.
The modular monitoring hub 64 may be designed with a first, e.g. top, interface 70 and a second, e.g. bottom, interface 72 , as illustrated schematically in FIG. 6 . The top interface 70 provides a hydraulic interface designed for connection to many types of hydraulic control lines 60 by providing appropriate adapters to form the connection. Similarly, bottom interface 72 also provides a hydraulic interface that may be connected to many types of hydraulic control lines 60 by providing the appropriate adapters. Multiple individual pressure and/or temperature sensors 58 , e.g. gauges, are connected between top interface 70 and bottom interface 72 to detect parameters of the control fluid moving through individual ports 68 . For example, individual sensors 58 can monitor corresponding hydraulic lines 60 at ports 68 through a “T” engagement as described above.
As a result, modular monitoring hub 64 enables the independent monitoring of multiple hydraulic control lines in control system 36 . In some applications, it may only be necessary to monitor an individual hydraulic line; although monitoring hub 64 simplifies the monitoring of greater numbers of control system hydraulic lines 60 .
The control and monitoring system 34 also may be designed to automatically detect the presence of riser instrumentation module system 38 , e.g. subsea monitoring module 48 or specific components of the system, such as modular monitoring hub 64 . For example, when monitoring hub 64 is installed in the string along riser 32 or subsea test tree 22 , the system 34 automatically detects its presence and enables control of the monitoring functions conducted with respect to control system 36 . In one specific embodiment, a topside system, such as topside monitoring system 50 and/or topside control system 46 may be utilized to detect the presence of modular monitoring hub 64 or other portions of riser instrumentation module system 38 . Once detected, the graphical user interface 56 on display 54 may automatically be updated to include data related to monitoring system 38 . In one example, the topside system accomplishes updating of the graphical user interface by monitoring a modbus port associated with the riser instrumentation module system 38 . When the riser instrumentation module is detected, the topside system reads communication frames from the module to ensure the topside system sets up appropriate graphics on the graphical user interface 56 .
System 34 may be constructed in a variety of configurations for use in many types of subsea wells. For example, many types of topside processing systems may be incorporated into the topside control system and topside monitoring system, respectively. Additionally, various sensors may be employed at the subsea test tree 22 or at other suitable subsea locations, and the mechanical structures used in mounting the sensors can be adjusted according to the configuration of the corresponding subsea components. Furthermore, various parameters and combinations of parameters may be measured to monitor the control system without compromising the SIL rating of the control system. This is accomplished by maintaining the monitoring system as a separate, independent system which does not utilize common sensors, common control circuitry, common communication lines, or other common components with the control system. Thus, the monitoring system is not able to interfere with operation of the control system.
The subsea test tree 22 and riser 32 also may be constructed in a variety of sizes and configurations. Depending on the specific subsea application, control system 36 may be utilized in a variety of safety controls, such as closing off the subsea well 20 at subsea test tree 22 . However, control system 36 also may be designed to control other or additional functions within subsea test tree 22 and/or along riser 32 .
Although only a few embodiments have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this application. Accordingly, such modifications are intended to be included within the scope defined in the claims herein and subsequent related claims. | A technique operates a valve system in a subsea test tree via a control system of a type suitable for gaining desired industry ratings. A monitoring system is utilized to monitor functions of the control system, but the monitoring system is independent from the control system. | 4 |
PRIORITY INFORMATION
[0001] The present application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 62/103,317, filed Jan. 14, 2015, the entire contents of which are expressly incorporated herein by reference.
TECHNICAL FIELD
[0002] The present embodiments relate to a method and service for protecting and managing personal digital information across multiple computing and storage platforms. More particularly, the present embodiments provide a method and service for storing sensitive and personal data on a hardware device.
BACKGROUND
[0003] The following definitions and explanations are intended to facilitate the understanding of the present embodiments without limiting their scope. A problem of securely storing and managing personal and private information today requires the users of personal computers and smart phones to install and run special purpose client applications specifically designed for such task. Exemplary programs are software products known as password managers, such as Lastpass, Dashlane, Roboform, 1Password, to name just a few. The operation of these commercial products typically requires users to authenticate themselves before they are granted access to information, data or services which are either financially relevant or confidential in nature. In other words, these products operate on the assumption that users can be effectively and securely authenticated before access to the stored data is provided to them.
[0004] The most common, simple and convenient form of authentication is based on the use of a static (i.e. fixed in time) credential (e.g. a password) which the user must provide to the application each time it is executed. In such scenario, the security of all the stored data relies totally on the secrecy of the authentication credential which is the only factor guarding against illegitimate usage by unauthorized individuals. The need to remember only one password to access all the data stored by password managers and the pivotal role this requirement plays in securing the private data is aptly highlighted by the customary appellation of a master password. One main argument in favor of using password managers requiring one single static master password is clearly the convenience, whereby the user can access all of his passwords anytime and anywhere as long as he remembers just one single secret credential.
[0005] The use of client password managers alone cannot, however, satisfy one prime requirement of users who wish to access their passwords on a number of separate devices which they typically access at different times during the day. This is the case, for example, of a laptop and smart phone which can be both used to access online banking services. The same password will be needed on both platforms where it can also be updated if required by the service provider or desired by the user. This example highlights the need to share and synchronize the passwords database across all devices accessed by the user, a task which clearly cannot be performed by independent instances of an installed client application running on separate disconnected platforms.
[0006] This latter consideration has prompted vendors of software password managers to develop and deploy cloud-based services designed to support the synchronization requirements of users. Typically, such service requires the payment of a yearly fee and the servers store and fetch from the cloud the latest password database previously copied in encrypted format over Internet from any of the installed database instances of the client application. When properly implemented by the vendors, this method can allow satisfying both the synchronization requirement as well as the need to provide an updated backup of the latest password database which can later be used for recovery purposes.
[0007] The picture that emerges from the above description of the typical way that software password managers operate can be summarized as follows. Users can install the client application on any of their digital platforms (laptop, PC, smart phone, etc.) and rest assured that by remembering only the master password they will be granted access to the latest version of the password database as long as they are connected to the Internet.
[0008] It is worthwhile to rephrase the above value proposition by highlighting the critical enabling underlying factors. While employing software password managers, users must: (1) rely on the confidentiality of the Master Password as the sole protection against unauthorized disclosure of all the contents of the password database. In other words, an attacker capable of sniffing or obtaining in other fraudulent way the master password can in principle and in practice gain access to all other passwords kept in the password database; (2) trust the product vendor and cloud service provider with the entire contents of the password database, albeit in encrypted format. In other words, notwithstanding all of the provided assurances, the user must accept to release his most valuable data to a third party in the hope that it will be securely handled according to all the agreed and implied policies and procedures; and (3) accept the limitation of synchronizing the password database across his computing platforms only when accessing Internet (i.e. while operating online). This requirement is at the root of the cloud as a service-for-fee and in some products (e.g. LastPass) it is also extended to the case of one password database on a single platform (i.e. passwords are all stored on the cloud and cannot be accessed offline).
[0009] The above three tenets of mainstream software password managers' usage, namely rely, trust, accept, pose serious questions regarding the practical security and suitability of such products in today's real-life digital information management scenarios. In fact, the use of a static master password has been shown to be ineffective against social engineering, brute force guessing and malware driven attacks whereby a third party is capable of obtaining the password for reading any amount of the private stored data before the legitimate user discovers the theft. Such attacks highlight the main weakness of static login credentials, i.e., the decoupling of the authentication credentials from the individual which they are purposing to authenticate. In this case, the simple knowledge of the password allows any individual to enjoy the authenticated status. In the case of password managers the threat can be even more effective than against web services which can stop providing the service when under attack. In fact, once an attacker copies the local password database he can perform brute force rounds to discover the Master Password (or equivalent secret) without any limitation on the number of attempts.
[0010] The use of static login credentials for applications requiring strong security assurances such as password managers has, therefore, been strongly criticized by security professionals warning about the catastrophic consequences of a theft or an unauthorized disclosure of the master password.
[0011] Indeed, having realized that this problem risks undermining the very foundations of their products' value proposition, vendors of software password managers have started advocating the adoption of small hardware devices as additional authentication means beyond the simple and sole master password.
[0012] The more general class of two-factor authentication methods which aim at binding the presence of the physical user to the requirements of the authorization procedure. The second factor in addition to the static credentials can be something that the user has (a physical device or a token external to the host device) or something that the user is (obtained using biometric sensors, e.g. via fingerprinting or iris scanning). Because of limitations due to the technology and to the still relatively high costs associated to mass deployments of biometric devices, the prevailing choice has until now been to provide users with small hardware tokens which the user must have and operate each time he requests access to the password database and cloud service.
[0013] However, both the static master password and the two-factor authentication methods described above suffer from one fundamental weakness, i.e., the need to rely on an application (a software controlled process executed on the host device) to authorize the user and communicate with the cloud sever.
[0014] For example, the application executing on the host device may require to retrieve a password, in which case the cloud sever may generate a random session key, and then protect the session key in such a way that it can be obtained only with the user-specific secret key kept in the hardware device owned by the user. With this approach, it would seem that no one except the legitimate user could receive the data, since only the password manager application can access the secret key and the secret key can never leave the device safely kept and operated by the user.
[0015] However, this approach has a weakness in that a rogue application, developed by a malicious programmer and executed on the user's host device—or on the programmer's device through remote connection—can make an identical request to the cloud server after obtaining all the necessary authentication data from the unaware user. In fact, the objective of the rogue application is only to access the sensitive cloud resources and not to know or extract the user-specific secret key from the hardware device. To obtain its goal, the rogue application can simply make the same authentication request to the cloud server that the client application would do using the user-specific secret, and thus obtain access to the sensitive data on the server. In this example, there is nothing to differentiate from the cloud server point of view the password manager's authentication request from that of the rogue application. Once this latter has gained access to the service, it can in principle operate independently from the legitimate application and from any further user input.
[0016] Remarkably, the weakness described above applies to all user-based authentication methods, regardless of the enabling technology applied to generate and store the secret access credentials. In fact, the roots of this vulnerability rest in the need for all user-based authentication methods to rely on the trustworthiness of the applications employed to communicate with the cloud service providers.
[0017] It is therefore clear that the security of cloud-enabled transactions is first and foremost dependent on the ability to authenticate executable code running on a host device, an issue which falls into the more general category of software security. The goal of providing reliable and practicable means for remotely authenticating software applications has been the subject of U.S. Pat. No. 8,713,705B2 and will not be further discussed here. Suffices to conclude, however, that the approach advocated by vendors of software password managers cannot claim to resolve in any definitive way the critical vulnerability tied to the user's authentication and authorization when employing a static Master Password, with or without additional “strong” authentication means.
[0018] The criticality mentioned above is clearly related to the catastrophic nature of the security failure which occurs once the authentication and authorization steps are bypassed by a malicious code or attacker, namely the exposure of the entire contents of the password database. Hence, it is highly desirable to improve prior art methods for authorizing access to private information and data, and to also remove the requirements and limitations imposed on the users of software password managers (rely, trust, and accept).
SUMMARY
[0019] An object of the embodiments is to substantially solve all the problems and/or disadvantages discussed above, and to provide at least one or more of the advantages described below.
[0020] It is therefore a general aspect of the embodiments to provide systems, methods, and modes in accordance with the following. In particular, a system for protecting the privacy associated with one or more encrypted data records includes: a host device operable to allow access to the one or more data records being in an encrypted format including encrypted data records, and upon an attempt to access the one or more encrypted data records transmitting a request for an encryption key for unencrypting the encrypted data records to a security device; and a security device remote from the host device operable to require one or more actions being taken by a user as a condition to providing said encryption key, and upon the success of said actions as said condition, transmitting said encryption key to the host device.
[0021] The host device can unlock the one or more encrypted data records upon receipt of the encryption key. The one or more encrypted data records can be resident on the host device. In addition, the one or more fields associated with each of the one or more encrypted data records can also be maintained on the host device, and the one or more encrypted data records associated therewith can be resident on the security device.
[0022] The host device and security device may be securely coupled over a telecommunications connection, with the connection being any one of a wireline and a wireless connection. The security device may be a system closed from external communications but in relation to the encrypted data records and one or more additional encrypted data records, and further may be operable to execute low level instructions in an embedded, secured processing system. The host device may include one or more software applications resident and executing on any one of: a personal computer; a tablet; a smart watch and a mobile communications device. The one or more aforementioned actions may be any one of: physical actuation by a user; entry of information by the user; and entry of biometric information by the user.
[0023] The system may further include a remote processing device accessible over the Internet, the remote processing device (a) able to access the encryption key, (b) being operable to require one or more items of information provided by a user as a condition to providing the encryption key, and (c) upon determining the items of information to be correct information, transmitting the encryption key to the host device.
[0024] The system may also include any one of: an out-of-band authentication of a user; and a dynamic authentication of a user upon the processing of one or more signals between the host device and the security device. The host device may be further operable to maintain the encryption key and to mark the encrypted data records to reflect that the encryption key is being maintained on the host device.
[0025] Also provided is a method for protecting the privacy associated with one or more encrypted data records accessible by a host device, with the method including: maintaining an encryption key for unencrypting the one or more records on a security device; upon an attempt to access the one or more encrypted records, transmitting a request for the encryption key to the security device; and requiring one or more actions to be taken in relation to the security device as a condition to providing the encryption key to the host device. The method can further include: unlocking the one or more encrypted records of the host device upon receipt of the encryption key.
[0026] The one or more encrypted data records may be maintained resident on the host device. Also, one or more fields associated with each of the one or more records can be maintained on the host device, and the one or more encrypted data records can be maintained resident on the security device. The method further includes securely coupling over a telecommunications connection the host device and security device, with the connection being any one of a wireline and a wireless connection. Also, low level instructions may be executed in an embedded, secured processing system on the security device. Also, the encryption key may be maintained on a remote processing device accessible over the Internet, and upon an attempt to access the one or more encrypted records, the method may require one or more items of information being provided by a user as a condition to providing the encryption key from the remote processing device.
[0027] Further, the above noted one or more actions may include any one of: physical actuation by a user; entry of information by the user; and entry of biometric information by the user. The method may further include any one of: an out-of-band authentication of a user; and a dynamic authentication of a user upon the processing of one or more signals between the host device and the security device.
[0028] Additionally is provided a method for protecting the privacy associated with one or more encrypted data records accessible, the method including: maintaining the encrypted data records resident on a device, the encrypted data records being operable to become unencrypted upon actuation of a unique encryption key; upon an attempt to access the one or more encrypted records, transmitting a request for the encryption key; and upon user action being taken remotely, actuating a received key comprising the unique encryption key to unencrypt the encrypted data records.
[0029] Furthermore, a method is provided for protecting the privacy associated with one or more encrypted data records accessible, the method including: maintaining a unique encryption key operable to unlock one or more encrypted data records, said encrypted data records being remote from a device; and upon actuation by a user, transmitting the encryption key to the remote device in order to permit unlocking of said one or more data records.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The above and other objects and features of the embodiments will become apparent and more readily appreciated from the following description of the embodiments with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures unless otherwise specified.
[0031] FIG. 1 illustrates a high level block diagram of a system for managing personal information according to aspects of the embodiments.
[0032] FIG. 2 illustrates the high level block diagram of FIG. 1 further illustrating a number of differing exemplary systems/devices that are used as a host according to aspects of the embodiments.
[0033] FIG. 3 illustrates the high level block diagram of FIG. 1 further illustrating a number of differing exemplary systems/devices that are used as a cloud server environment according to aspects of the embodiments.
[0034] FIG. 4 illustrates exemplary embodiments of a hardware security device according to aspects of the embodiments.
[0035] FIG. 5 illustrates a first embodiment of an exemplary host device including an application capable of executing operating system resources and memory locations storing information according to aspects of the embodiments.
[0036] FIG. 6 illustrates a second embodiment of an exemplary host device including an application capable of executing operating system resources and memory locations partitioned into unboxed and boxed records of stored information according to aspects of the embodiments.
[0037] FIG. 7 illustrates an exemplary hardware (“security”) device including an application capable of executing instructions and associated memory locations of the same in accordance with aspects of the embodiments.
[0038] FIG. 8 illustrates an exemplary remote system including one or more resources running remote applications and memory locations pertaining to the same, together comprising components of an exemplary Internet cloud according to aspects of the embodiments.
[0039] FIG. 9 illustrates the block diagram of FIG. 1 further illustrating an exemplary host, an exemplary security device and an exemplary Internet cloud with the greater detail associated with FIGS. 4-8 respectively, in accordance with certain aspects of the embodiments.
[0040] FIG. 10 illustrates a block diagram of a system high level architecture in accordance with certain aspects of the embodiments.
DETAILED DESCRIPTION
I. Overview
[0041] The embodiments are described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the inventive concept are shown. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout. The embodiments can, 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 inventive concept to those skilled in the art. The scope of the embodiments is therefore defined by the appended claims.
[0042] The following embodiments are discussed, for simplicity, with regard to the terminology and structure of the apparatus and methods employed. However, the embodiments are not limited to the foregoing.
[0043] Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the embodiments. Thus, the appearance of the phrases “in one embodiment” on “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular feature, structures, or characteristics can be combined in any suitable manner in one or more embodiments.
[0044] In exemplary embodiments, a secure and flexible method and service is provided for authorizing and managing personal information on any number of client devices. It allows removing the requirements and limitations imposed on the users of software password managers (rely, trust, and accept) and overcomes all major drawbacks of known devices inasmuch the user is now always in control of his most sensitive data, but can still access them under all operational conditions.
[0045] Furthermore, it is practically impossible for a malicious programmer or malware code to steal all the personal information at once even when using a previously sniffed password required by the device or the server validation before each new request for access by the application.
[0046] These embodiments can be applied to three atomic operational conditions: (1) disconnected, meaning that the software password manager application is executed on a host without connection to a security device; (2) connected, meaning that the software password manager application is executed on the host while connected with a hardware device (e.g. over Bluetooth, USB, or other direct means), and (3) online, meaning that the software password manager application is executed on the host while able to communicate with a remote escrow service over Internet. Exemplary embodiments are set forth in greater detail below.
[0047] While there are numerous embodiments that enable authentication and personal information management in the described configurations and architecture, it is however expected that one with ordinary skill in the art will be capable of extending the concepts and principles disclosed herein to alternative embodiments by replacing the host, hardware device and/or the remote components with different or additional components capable of executing similar tasks. Examples of such alternative embodiments include the case in which the hardware and remote components are exchanged (i.e., the device authenticates the software application) and the case in which the remote system or the host or both are replaced by a mobile or tamper-proof secure device.
[0048] 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.
II. Overall Environment
[0049] FIG. 1 portrays an exemplary overall environment in which a method and service for managing personal information data using a software application executing on a host computer connected to a hardware device and capable of exchanging data over Internet with a computing service according to the present invention may be used.
[0050] In reference to FIG. 1 , an aspect of the present embodiments provides methods of distributing a password database information among up to three storage and computing systems: (1) the first, a host 200 runs a software password manager application, while (2) the second, a hardware device or “security” device 100 , and (3) the third, a remote system, for example running on the Internet cloud 300 , respectively provide additional security, data storage and authorization functions. As shown, exemplary host 200 and security device 100 are coupled 130 for communications, exemplary host 200 and cloud 300 are coupled 110 for communications, and cloud 300 and security device 100 are coupled 120 through host 200 for communications respectively between them.
[0051] In one embodiment, the password manager application, a software controlled process executed on the host device 200 , is installed and run on one or more of the computing devices operated and owned by the user (PC, laptop, tablet, smart phone, etc.) and capable of connecting to the Internet. The user is also provided with security device 100 capable of storing and computing data, as well as of visualizing information and logging user confirmation via physical action (e.g., by pressing a button, swiping a finger, etc.) or entering a password via a keypad. For example, the user may be required to validate security-critical operations or requests, such as authentication and authorization procedures by pressing a button on device 100 . In this exemplary embodiment, the personal information is stored in certain logically but not necessarily physically distinct databases as described below.
III. Exemplary Host Device Systems
[0052] FIG. 2 is the same as FIG. 1 except that it illustrates a number of differing exemplary systems/devices that are used as host device 200 . Specifically, mobile device 208 , tablet 210 and a plurality of computers, tablets and servers connected over a LAN or WAN architecture 212 are shown, though any combination of hardware executing resident or non-resident software is capable of being used in accordance with the embodiments.
IV. Exemplary Remote Cloud Server Systems
[0053] FIG. 3 is the same as FIG. 1 except that it illustrates a number of differing exemplary systems/devices that are used as a remote system comprising Internet cloud 300 . Specifically, near remote server 302 , distant remote server 306 , a server/client environment (connected over a LAN) 304 , and a plurality of computers, tablets and servers connected over a LAN or WAN architecture 308 are shown, though any combination of hardware executing resident or non-resident software is capable of being used in accordance with the embodiments.
V. Exemplary Security Device Systems
[0054] FIG. 4 illustrates exemplary embodiments of hardware device 100 , namely exemplary devices 140 , 150 and 160 . Exemplary hardware device 140 includes an exemplary actuator device 115 and an output indication device 112 , which can comprise an indicator light. Actuator device 115 is any resident or non-resident component that is physically actuated on the device. In an exemplary embodiment, actuator device 115 is a button which is depressed, serving as an input to the processor of device 140 . Output indication device 112 may be, for example, an indicator light serving as output from the processor of device 140 to provide information to the user, such as that the user's actuation of actuator device 115 has been recognized or accepted.
[0055] Exemplary hardware device 150 includes the foregoing exemplary actuator device 115 and indicator light 112 , and further includes expanded display module 107 and expanded input module 106 . Display module 107 provides additional input to the user further to a light signal. Expanded input module 106 is adapted to receive input from the user including without limitation biometric input, voice input and other user-associated input which are recognized by the processor of device 150 .
[0056] Exemplary hardware device 160 includes the foregoing exemplary actuator device 115 , indicator light 112 , expanded display module 107 and expanded input module 106 . Device 160 further includes a full keyboard for user generated input.
VI. Exemplary Implementation of Host Device Systems
[0057] In reference to FIG. 5 , host device 200 (e.g. PC, smart phone, tablet or other personal computing device) comprises a client application 201 , such as for example software programming code or a computer program product. Client application 201 can be a software password manager. In the exemplary embodiment, client application 201 is embedded within, or installed on, the host device 200 , where it can be executed within the operating system's context comprising all the resources and objects that are required for the execution of the client application 201 on the host device 200 .
[0058] Such resources and objects include the ability to enter, store, retrieve, view, change, receive and transmit personal information data to/from hardware security device 100 and to/from processors running remotely in cloud 300 . All of these devices are coupled or linked together over wired or wireless connections 110 in any fashion characterized and enabled by specific middleware, topology, protocol, and architecture providing the desired security and performance assurances.
[0059] FIG. 5 also illustrates host 200 in greater detail, including in addition to application 201 , locations 202 - 205 where either data or pointers associated with memory locations are stored. In the illustrated embodiment, according to predefined constraints, required usage or individual preferences, the personal information data entered by the user of the system via client application 201 is stored on the host in data collections (e.g., in relational databases) 202 - 205 .
[0060] FIG. 6 illustrates an alternative implementation where the memory locations are partitioned for the type of data held and marked accordingly. The implementation is further described below.
VII. Exemplary Implementation of Security Device Systems
[0061] FIG. 7 an exemplary embodiment of the memory associated with security device 100 . In particular, FIG. 7 illustrates the storage components 102 - 108 of device 100 in greater detail. Personal information data transmitted from host 200 to hardware device 100 over link 130 is stored in data collections 102 - 108 , after operating on them by executing persistent memory and program code 101 (e.g., firmware). In exemplary embodiments, data collection 108 stores encrypted data, while data collections 102 - 105 are used for storage of encryption keys as hereinafter described.
VIII. Exemplary Implementation of Remote Cloud Server Systems
[0062] FIG. 8 is an exemplary embodiment of the memory associated with a remote server system running its own operating system and being remotely accessible over one or more telecommunications connections comprising Internet cloud 300 . In exemplary embodiments, data collections 302 - 308 store encryption keys associated with one or more data records resident on either host device 200 or security device 100 . In exemplary embodiments, the remote server in cloud 300 can also store and access encrypted data in memory locations (not shown).
IX. Exemplary Implementation of Host Device, Security Device and Cloud Server Systems
[0063] FIG. 9 illustrates the exemplary host device 200 of FIGS. 5, 6 , the exemplary security device 100 of FIG. 7 , and the exemplary remote server system of cloud 300 of FIG. 8 . As shown, host device 200 and cloud 300 are coupled by connection 110 ; host device 200 and device 100 are coupled by connection 130 ; cloud 300 and device 100 are coupled by connection 120 .
[0064] In an exemplary embodiment, data contained within database 203 is stored on host 200 running password manager software 201 . Database 203 is kept permanently encrypted while the application is executed, but the database records and their keys can be accessed and individually decrypted after the user enters a secret password without any further or external confirmation. Records stored in this database are, therefore, as secure as those managed by a software-only password manager, since their security ultimately hinges on the privacy of the secret password and on the security of the application itself.
X. Exemplary Overview of Memory and Processing By Host Device, Security Device and Cloud Server Systems
[0065] In exemplary embodiments, the following databases can be used on host device 200 in coordination with security device 100 :
[0066] (1) A first database is stored on the host running the password manager software. This database is kept permanently encrypted while the application is executed, but the database records and their keys can be accessed and individually decrypted after the user enters a secret password without any further or external confirmation. Records stored in this database are, therefore, as secure as those managed by any typical software-only password manager, since their security ultimately hinges on the privacy of the secret password and on the security of the application itself.
[0067] (2) A second database, is also stored on the host running the password manager software. This database is kept permanently encrypted while the application is executed, and it contains data related to records which can be accessed and individually decrypted only after the user confirms via physical action on the hardware device. This database stores the record's encrypted data, but none of the keys required to individually decrypt them. It will be possible to decrypt and view information from these records under two operational conditions: the hardware device is connected (over Bluetooth, USB, etc.) to the application which is requesting to view the record's data and the User has confirmed the request by physical action on the device (e.g. by swiping his finger). Optionally, the application can be authenticated by the device, such as for example found in U.S. Pat. No. 8,713,705B2, incorporated by reference herein in its entirety.
[0068] (3) A third database is stored on the hardware device and contains all records and their encryption keys. This database is kept permanently encrypted using keys which are never shared with any other system, for example non-extractable key(s) stored on a secure micro-controller or similar secure storage. Before sharing any record data with the client application, the data are encrypted/decrypted as needed on the device and securely sent to the application. This database is effectively the union of the first, second and fifth database described below, and is the “master copy” of all private information stored by the user. It is the sole and unique synchronization source across all computing hosts accessed by the user.
[0069] (4) A fourth database that can be stored on any storage medium connected to the host running the application. This database contains information and data for all private records and is a backup database kept permanently encrypted with a key derived from a complex backup password created during the initial system configuration and stored on the third database, for example. This database is updated with the data from the third database each time the client application is executed while connected to the device and is never decrypted by the application during standard usage: it is reserved, for example, only for restore purposes in the case of partial or catastrophic data loss from the third database or in order to restore all data on a new or additional hardware device.
[0070] (5) A fifth database containing all or part of the encryption keys of the records stored in the second database. The keys are kept individually permanently encrypted and can be provided one at a time to the client application as will be described below.
XI. Exemplary Implementation of Memory and Processing By Host Device, Security Device and Cloud Server Systems
[0071] The aforementioned is further explained as follows. In an exemplary embodiment, database 202 is stored on host 200 running password manager software 201 . Here, database 202 keeps encrypted data while the application is executed. The encryption key is kept on security device 100 , particularly in memory locations 102 - 105 . In the exemplary embodiment, security device 100 runs low level instructions such as assembler language embedded in firmware. In this and numerous other embodiments, device 100 lacks an open operating system, but instead runs the low level instructions in response to certain input received over a secure transaction. As device 100 is closed from non-authenticated communications, and purposefully does not include a generic operating system, it provides a very secure environment for maintaining the encryption key. Encryption keys for individual records are transmitted from device 100 back to host 200 when the user actuates device 100 , by either actuating device 115 , or providing required biometric or user-associated input via expanded input module 106 .
[0072] In another exemplary embodiment, database 204 is stored on host 200 running password manager software 201 . Here, database 204 keeps only fields associated with encrypted data. Both the encrypted data associated with the fields, as well as the encryption keys pertaining to each of the respective encrypted data, are kept in security device 100 . In particular, device 100 keeps the encrypted data in memory locations 108 , and the encryption keys in memory locations 102 - 105 . In this embodiment, again device 100 is a closed system running low level instructions as above noted, except that both encryption keys and encrypted individual records of data corresponding to the fields of database 204 , are maintained on the device. Again, actuation by the user via actuating device 115 or expanded input module 106 is required before the data records are encrypted by the encryption keys. In response to the user actuation, the unencrypted data is transmitted over secure connection 130 back to host device 200 .
[0073] In another exemplary embodiment, database 205 is stored on host 200 running password manager software 201 . Here, database 205 keeps a combination of some fields associated with encrypted data as well as some encrypted data, itself. Here, encrypted data associated with the one or more of the fields, encryption keys for such encrypted data of the fields, as well as encryption keys for encrypted data in database 205 are kept on security device 100 . In particular, on device 100 the encrypted data are located in memory locations 108 , and the encryption keys are located in memory locations 102 - 105 . In this embodiment, again device 100 is a closed system running low level instructions as above noted, except that both encryption keys and encrypted individual records of data corresponding to the fields of database 204 , are maintained on the device. Again, actuation by the user via actuating device 115 or expanded input module 106 is required before the data records are encrypted by the encryption keys. In response to the user actuation, for the data for which only fields are stored in database 205 , the encrypted data is unencrypted via encryption keys, and transmitted back to host device 200 over a secure connection. In addition, in response to the user actuation, for data for which the encrypted data itself is kept in database 205 , the respective encryption keys required are transmitted back to host device 200 over a secure connection, where the data is then unencrypted.
[0074] In exemplary implementations, rather than using particular memory locations for encrypted data, fields associated with encrypted data and/or encryption keys, the memory locations can be partitioned for the type of data held and marked accordingly. For example, in the exemplary embodiment of FIG. 6 , the memory locations of host device 200 and accessed by client application 201 are designated as “boxed” records 206 and “unboxed” records 207 . The boxed records are data which are explicitly marked as such, which include encrypted data stored locally on device 200 , and for which encryption keys are kept on the security device 100 . The unboxed records are data which are explicitly marked as such, which include encrypted data stored locally on device 200 , and for which encryption keys are kept on host device 100 itself. In an exemplary embodiments, boxed data may be transformed by the user's actions to unboxed, and vice versa, as the encryption keys are respectively provided from device 100 , or transmitted to device 100 , and the memory locations are re-designated appropriately.
[0075] In exemplary embodiments, any particular one or any combination of the aforementioned features and functions of device 100 , including of its respective component program code 101 , data collections 102 - 108 and processor(s), are specifically carried out by one or more remote devices, such as remotely operated servers, in cloud 300 . In particular, in exemplary embodiments, encryption keys are stored in memory locations 302 - 308 and/or encrypted and/or unencrypted data are stored in additional memory locations (not shown). In one particular exemplary embodiment, no user actuation (analogous to actuation of actuator device 112 ) is required for encrypted or unencrypted data, or encryption keys in encrypted or unencrypted format, to be transmitted to host device 200 . In certain such exemplary embodiments, the processors of cloud 300 are (1) in closed systems, running for example low level instructions with limited, secure connections to other devices as above note with respect to device 100 , while in other exemplary embodiments, (2) the processors of cloud 300 are in open systems, running on defined operating systems and with multiple inputs/outputs over open network connections that are not necessarily secure, while in yet additional embodiments, (3) the processors of cloud 300 run in environments that are a combination of the foregoing (1) closed systems and (2) open systems.
[0076] In exemplary embodiments, additional authentication is also used in addition to the above processes, both individually and in combined fashion. An exemplary additional authentication method is an out-of-band authentication of the user. Another exemplary authentication method employs dynamic authentication of a user pursuant to U.S. Pat. No. 8,713,705, entitled “Application Authentication System and Method,” and of common inventorship and assignee as the present embodiments, which is incorporated herein by reference in its entirety.
XII. Exemplary System High Level Architecture
[0077] FIG. 10 illustrates a high level architecture of an exemplary implementation of the foregoing inventive concepts as used by EISST Ltd. of the United Kingdom in its Qubi product series. In the illustrated embodiment, host device 200 is running an app instance, and communicatively coupled to cloud server 300 and security device 100 . In addition, a backup archive 1000 serves to provide archival functionality for host device 100 .
[0078] The terminology employed in relation to FIG. 10 is detailed in the tables provided below. In particular, the tables are defined as follows. Table 1 provides a resource dictionary for databases and encryption employed; Table 2 provides a glossary of symbols defining exemplary encryption operations; Table 3 provides definitions of the databases used respectively for records (boxed and unboxed), encryption keys and for the backup archives; and Table 4 provides exemplary encryption technologies employed.
[0079] Beginning with host (QubiApp) device 200 , included are: 1101 —QubiApp instance; 1102 —Salt values—four generated salt values; 1103 —<LKK>-LKK encrypted with [BXK]LK; 1104 —<UDBK>-UDBK encrypted with [BXK]UD; 1105 —<LDBK>-LDBK encrypted with [BXK]LD; and 1106 —<UDB>-UDB encrypted with UDBK.
[0080] Backup archive 1000 includes: 1201 —QubiPass backup archive; 1202 —<UDBKB>-<UDBK> encrypted with BDBK; 1203 —<LDBKB>-<LDBK> encrypted with BDBK; 1204 —<LKKB>-<LKK> encrypted with BDBK; 1205 —<BDBKB>-BDBK encrypted with BXMK hashed with SALTBDB; 1206 —Salt values—Backup copy of four generated salt values, plus SALTBDB; 1207 —<UDBB>—Copy of <UDB>, and 1208 —<KDBB>—Collection of <LK> encrypted with BDBK.
[0081] Cloud server (QubiCloud) 300 includes: 1302 —QCK—QubiCloud key/salt encryption key; 1303 —QCDB—QubiCloud Database; 1304 —QCL—QubiCloud user login; 1305 —[QCP]—QubiCloud user password hashed with SALTQCP; 1306 —<SALTQCP>-SALTQCP encrypted with QCK; 1307 —<QCAT>-QCAT encrypted with QCK; 1308 —[[BXK]A]—[BXK]A hashed with SALTBXK; 1309 —<SALTBXK>-SALTBXK encrypted with QCK; and 1310 —KDB—Collection of <LK>.
[0082] Security (QubiBox) device 100 includes: 1402 —Encrypted file system; 1403 —UDB—Copy of UDB; 1404 —KDB—Collection of <LK>; 1405 —[BXK]—Hashed BXK; 1406 —[BXMK]—Hashed BXMK; 1407 —BDBk—Backup encryption key; 1408 —<UDBK>—Copy of <UDBK>; 1409 —<LDBK>—Copy of <LDBK>; 1410 —<BDBK>-BDBK encrypted with BXMK hashed with SALTBDB; 1411 —<LKKB>—Copy of <LKK>; 1412 —Salt values—Copy of four generated salt values, plus SALTBDB; 1413 —SDEK—Storage Encryption Key; and 1414 —FSEK—File system encryption key.
[0000]
TABLE 1
Term
Definition
QubiPass or QP
The bundled QubiApp + QubiBox product
QubiApp or QA
QubiPass Manager (the software client component of
Application or App
the QubiPass product)
QubiCloud or QC
The cloud key escrow service provided to Users who
wish to view Boxed records in disconnected mode.
BoxKey or BXK
The password required to run the QubiApp in both
connected and disconnected modes
BoxMasterkey or
The password required for special operations, such as
BXMK
unblocking a QubiBox and recovering data from a
backup archive. This password is used to backup
(wrap) all the Records in encrypted format by the
Application. The BoxMasterkey is defined once by
the User and can be changed through the QubiApp
Settings.
UDB (Unified
Database of unboxed records with their keys and
Database)
Boxed Records without keys kept on the host
KDB (Keys
Database of keys for decrypting the boxed records
Database)
BDB (Backup
Archive with all the data required for a full restore
Archive)
LK
Key which is used to encrypt a Boxed record, unique
for each record
UK
Key which is used to encrypt an Unboxed record,
unique for each record
UDB-K
Key which is used to encrypt the UDB
LDB-K
Key which is reserved for future use
BDB-K
Key which is used to encrypt the BDB
LK-K
Key which is used to encrypt the LK and UK
[BXK]-LK
Derivative of BXK which is used to encrypt LK-K
[BXK]-LD
Derivative of BXK which is used to encrypt LDB-K
[BXK]-UD
Derivative of BXK which is used to encrypt UDB-K
[BXMK]-BD
Derivate of BXMK which is used to encrypt BDB-K
QCK
QubiCloud key/salt encryption key, generated once
during the deployment, stored outside QCDB
QCL
QubiCloud user login
QCDB
QubiCloud Database
QCP
QubiCloud user password
SYNCK
Randomly generated 256-bit AES key, used to
encrypt KDB wholly or partially before transferring it
to QubiCloud. Protects the contents of KDB from
QubiApp
QCPuK
Public component of QCPK
QCAT
Randomly generated 128-bit Authorization Token
issued to QubiApp by QubiCloud after authenticating
the user
QCPK
QubiCloud's 2048-bit RSA private key
[0000]
TABLE 2
Encryption Notation
Definition
< >
Encrypted quantities are indicated by enclosing the
quantity within brackets, e.g. <Key>
[ ]
Hashed quantities are indicated by enclosing the
quantity within square parenthesis, e.g. [Key]
⊙
Symmetric encryption (decryption) operation is
indicated by the ⊙ symbol followed by the encryption
(decryption) key, e.g. Key ⊙ [Key] → <Key>
-U
Quantities with a -U appended to the right indicate
entries from the User
≡
Comparison operation is indicated by the ≡ symbol
between two quantities
[0000]
TABLE 3
Database
Definition
UDB (Unified
Database of unboxed records with their keys and
Database)
Boxed Records without keys kept on the host
KDB (Keys Database)
Database of keys for decrypting the boxed records
BDB (Backup
Archive with all the data required for a full restore
Archive)
[0000]
TABLE 4
Encryption
Definition
Cryptographically
A pseudo-random number generator designed to be
Secure Pseudo-
cryptographically secure, providing a high level of
Random Number
randomness and being completely unpredictable (see
Generator or
for example:
CSPRNG
http://en.wikipedia.org/wilci/CryptGenRandom)
SHA-256
Secure hash function computed with a 32-bit words
(http://en.wikipedia.org/wiki/SHA-2)
RIPEMD-256
RACE Integrity Primitives Evaluation Message
Digest (http://en.wikipedia.org/wiki/RIPEMD)
PBKDF2
Password-Based Key Derivation Function 2
(http://en.wikipedia.org/wiki/PBKDF2)
Salt
Random data used as an additional input to a one-way
hashing function that “hashes” the password or
passphrase
XIII. Exemplary Setup and Configuration for QubiApp, QubiBox and QubiCloud
[0083] The setup and configuration of QubiApp, QubiBox and QubiCloud may be in accordance with the following exemplary embodiment.
[0084] 1. The User is asked to choose a BoxKey (BXK) with given complexity requirements.
[0085] 2. If the Host is already set up in Disconnected mode, check if the given BXK can be used to decrypt existing <UDBK>. If not, require the User to enter valid BXK or ask if the existing keys and databases can be removed.
[0086] 3. The User is asked to choose a BoxMasterkey (BXMK) with given complexity requirements.
[0087] 4. QubiApp generates three random AES256 encryption keys: UDBK, LDBK, LKK
[0088] 5. QubiApp generates four fixed-length random salt values. The length of the salt values must be 128 bits.
[0089] 6. QubiApp generates four salted consecutive hashes from BXK in the following order: [BXK]LK→[BXK]LD→[BXK]UD→[BXK]A. The salt value must be stored on the Host and the Device with the respective key encryption key, encrypted with BXK, for future uses.
[0090] 7. Use the hashes derived from BXK as key encryption keys: UDBK ⊙ [BXK]UD→<UDBK>LDBK ⊙ [BXK]LD→<LDBK >LKK ⊙ [BXK]LK→<LKK>
[0091] 8. Create UDB, the database for storing Records and their encryption keys (if it doesn't exist)
[0092] 9. Store <UDB>, <UDBK>, <LDBK> and <LKK> on the Host
[0093] 10. QubiApp initiates QubiBox personalization by sending BXMK as PUK
[0094] 11. QubiBox generates embedded file system encryption key: FSEK
[0095] 12. QubiBox formats the embedded file system using FSEK
[0096] 13. QubiBox reads Storage Encryption Key from the protected memory: SDEK
[0097] 14. QubiBox encrypts FSEK with SDEK: FSEK ⊙ SDEK→<FSEK>
[0098] 15. QubiBox stores <FSEK> on the embedded file system header
[0099] 16. QubiBox opens the embedded file system using FSEK
[0100] 17. QubiBox hashes BXMK: [BXMK]
[0101] 18. QubiBox stores [BXMK] on the embedded file system and marks it as non-exportable
[0102] 19. QubiBox generates 128-bit random salt value on the device: SALTBDB
[0103] 20. QubiBox generates a salted hash from BXMK with SALT BDB with 2000 iterations: [BXMK] BD
[0104] 21. QubiBox generates a random AES256 encryption key: BD BK
[0105] 22. QubiBox stores BD BK on the embedded file system and marks it as non-exportable
[0106] 23. QubiBox stores SALT BDB on the embedded file system and marks it as exportable
[0107] 24. QubiBox encrypts BDB K : BDB K ⊙ [BXMK] BD →<BDB K >
[0108] 25. QubiBox stores <BDB K > on the embedded file system and marks it as exportable
[0109] 26. QubiApp logs into QubiBox with BXMK as PUK
[0110] 27. QubiApp sends BXK to QubiBox as PIN
[0111] 28. QubiBox hashes BXK: [BXK]
[0112] 29. QubiBox stores [BXK] on the embedded file system and marks it as non-exportable
[0113] 30. The User logs into QubiApp (see 3.4 or 3.5 of QubiApp Key & DB Management)
[0114] 31. QubiApp reads QCAT from UDB
[0115] 32. QubiApp sends QCAT, [BXK- ] A and the device serial number to QubiCloud
[0116] 33. QubiCloud verifies if QCAT is valid with QCDB
[0117] 34. QubiCloud stores the device serial number in the QCDB
[0118] 35. QubiCloud generates a 128-bit salt for hashing the [BXK] A and stores it in the QCDB: SALT BXK
[0119] 36. QubiCloud generates a salted hash from [BXK] A and SALT BXK : [[BXK] A ]
[0120] 37. QubiCloud stores [[BXK] A ] in the QCDB
[0121] 38. Clear all setup and initialization objects from process memory of the Host
XIII. Certain Computer Implementation of the Embodiments
[0122] As also will be appreciated by one skilled in the art, the various functional aspects of the embodiments can be provided with numerous technologies. Accordingly, the embodiments can take the form of an entirely hardware embodiment or an embodiment combining hardware and software aspects. Further, the embodiments can take the form of a non-transitory computer program product stored on a computer-readable storage medium having computer-readable instructions embodied in the medium. Any suitable computer-readable medium can be utilized, including hard disks, CD-ROMs, digital versatile discs (DVDs), optical storage devices, or magnetic storage devices such a floppy disk or magnetic tape. Other non-limiting examples of computer-readable media include flash-type memories or other known types of memories.
[0123] Further, those of ordinary skill in the art in the field of the embodiments can appreciate that such functionality can be designed into various types of circuitry, including, but not limited to field programmable gate array structures (FPGAs), application specific integrated circuitry (ASICs), microprocessor based systems, among other types. A detailed discussion of the various types of physical circuit implementations does not substantively aid in an understanding of the embodiments, and as such has been omitted for the dual purposes of brevity and clarity. However, as well known to those of ordinary skill in the art, the systems and methods discussed herein can be implemented as discussed, and can further include programmable devices.
[0124] Such programmable devices and/or other types of circuitry as previously discussed can include a processing unit, a system memory, and a system bus that couples various system components including the system memory to the processing unit. The system bus can be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. Furthermore, various types of computer readable media can be used to store programmable instructions. Computer readable media can be any available media that can be accessed by the processing unit. By way of example, and not limitation, computer readable media can comprise computer storage media and communication media. Computer storage media includes volatile and nonvolatile as well as removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CDROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the processing unit. Communication media can embody computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and can include any suitable information delivery media.
[0125] The system memory can include computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) and/or random access memory (RAM). A basic input/output system (BIOS), containing the basic routines that help to transfer information between elements connected to and between the processor, such as during start-up, can be stored in memory. The memory can also contain data and/or program modules that are immediately accessible to and/or presently being operated on by the processing unit. By way of non-limiting example, the memory can also include an operating system, application programs, other program modules, and program data.
[0126] The processor can also include other removable/non-removable, volatile/nonvolatile, and transitory/non-transitory computer storage media. For example, the processor can access a hard disk drive that reads from or writes to non-removable, nonvolatile, and non-transitory magnetic media, a magnetic disk drive that reads from or writes to a removable, nonvolatile, and non-transitory magnetic disk, and/or an optical disk drive that reads from or writes to a removable, nonvolatile, and non-transitory optical disk, such as a CD-ROM or other optical media. Other removable/non-removable, volatile/nonvolatile, and non-transitory computer storage media that can be used in the operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM and the like. A hard disk drive can be connected to the system bus through a non-removable memory interface such as an interface, and a magnetic disk drive or optical disk drive can be connected to the system bus by a removable memory interface, such as an interface.
[0127] The embodiments discussed herein can also be embodied as computer-readable codes on a computer-readable medium. The computer-readable medium can include a computer-readable recording medium and a computer-readable transmission medium. The computer-readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer-readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs and generally optical data storage devices, magnetic tapes, flash drives, and floppy disks. The computer-readable recording medium can also be distributed over network coupled computer systems so that the computer-readable code is stored and executed in a distributed fashion. The computer-readable transmission medium can transmit carrier waves or signals (e.g., wired or wireless data transmission through the Internet). Also, functional programs, codes, and code segments to, when implemented in suitable electronic hardware, accomplish or support exercising certain elements of the appended claims can be readily construed by programmers skilled in the art to which the embodiments pertains.
XIV. Certain Computer Implementation of the Embodiments
[0128] It should be understood that this description is not intended to limit the embodiments. On the contrary, the embodiments are intended to cover alternatives, modifications, and equivalents, which are included in the spirit and scope of the embodiments as defined by the appended claims. Further, in the detailed description of the embodiments, numerous specific details are set forth to provide a comprehensive understanding of the claimed embodiments. However, one skilled in the art would understand that various embodiments can be practiced without such specific details.
[0129] Although the features and elements of aspects of the embodiments are described being in particular combinations, each feature or element can be used alone, without the other features and elements of the embodiments, or in various combinations with or without other features and elements disclosed herein.
[0130] This written description uses examples of the subject matter disclosed to enable any person skilled in the art to practice the same, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and can include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims.
[0131] The above-described embodiments are intended to be illustrative in all respects, rather than restrictive, of the embodiments. Thus the embodiments are capable of many variations in detailed implementation that can be derived from the description contained herein by a person skilled in the art. No element, act, or instruction used in the description of the present application should be construed as critical or essential to the embodiments unless explicitly described as such. Also, as used herein, the article “a” is intended to include one or more items.
[0132] All patents and applications and publications discussed above are hereby incorporated herein by reference in their entireties. | A system and corresponding method for protecting the privacy associated with one or more encrypted data records includes a host device and a security device. The host device is operable to allow access to the one or more data records being in an encrypted format including encrypted data records, and upon an attempt to access the one or more encrypted data records transmitting a request for an encryption key for unencrypting the encrypted data records to a security device. The security device is remote from the host device and is operable to require one or more actions being taken by a user as a condition to providing the encryption key, and upon the success of the actions as the condition, transmitting the encryption key to the host device. The host can then unlock the encrypted data records upon receipt of the encryption key. In different implementations, either the encrypted data records can be resident on the host device, or there can be fields associated with each of the encrypted data records maintained on the host device, and the encrypted data records associated with them can be resident on the security device. Further included is a remote processing device such as a server accessible over the Internet, the remote processing device able to access the encryption key, to require one or more items of information provided by a user as a condition to providing the encryption key, and upon determining the items to be correct, transmitting the encryption key to the host device. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to an improved rope structure, and more specifically to a composite rope structure having a core consisting primarily of high modulus fibers, and a sheath consisting primarily of a relatively lower modulus fiber having high abrasion resistance.
The fibers comprising the core are, as indicated, primarily high modulus fibers while the fibers comprising the sheath are relatively lower modulus fibers having high abrasion resistance. The composite structure has been found to provide a finished product having properties which exceed the sum of the individual parts, thereby providing and contributing to a synergistic effect in the overall finished product.
In the preparation of ropes or lines, the utilization of high modulus fibers alone normally provides two disadvantages, the first being the high specific gravity of these fibers, the second being the generally low abrasion resistance. For certain applications, such as utilization as a water ski-tow rope, the use of high modulus fibers may provide a finished product with a specific gravity greater than 1.0, thereby having a non-floating line. Furthermore, the low abrasion resistance of these fibers limits or restricts the application of the finished line for a wide variety of uses.
The utilization of lower modulus fibers will, of course, provide a specific gravity normally less than 1, however the stretch characteristics of such fibers when braided into a line also limits the application of the braided product. In the present structure, a high modulus core is covered with a sheath of a different fiber having high abrasion resistance and low specific gravity, thereby achieving a finished rope product with a specific gravity less than 1, and having high strength and low stretch.
The core material is preferably prepared from fibers which consist essentially of a polyimide of an aromatic tetracarboxylic acid dianhydride having the recurring unit with the structural formula: ##EQU1## wherein R is a tetravalent aromatic radical, and wherein R is a divalent benzenoid radical. Fibers of such polyimide materials are co-mercially available. The sheath material, as indicated, consists primarily of filaments of a polyolefin selected from the group consisting of polypropylene and polyethylene. Such polyolefin filaments are, of course, commercially available.
Therefore, it is a primary object of the present invention to provide an improved composite rope structure having low stretch, high strength, and high abrasion resistance.
It is a further object of the present invention to provide an improved braided rope structure which comprises a blend of filaments braided together to form the composite line structure, and including a braided core of filaments having a high modulus and a sheath braided thereover, the sheath comprising filaments of lower modulus, but significantly higher abrasion resistance.
It is a further object of the present invention to provide an improved rope comprising a plurality of discreet filaments, the filaments being arranged in a core and sheath structure, the composite of which forms a high strength core and a high abrasion resistance sheath, and with the composite structure having high strength and low stretch characteristics.
Other further objects of the present invention will become apparent to those skilled in the art upon a study of the following specification, appended claims and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating the elongation in percent as a function of test load, for a number of test samples; and
FIG. 2 is a perspective view of a typical rope prepared in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with the preferred embodiment of the present invention, and with particular attention being directed to FIG. 2 of the drawings, it will be seen that the rope structure generally designated 10 comprises an inner core component 11 along with an outer sheath component 12. Core 11 is comprised of a plurality of multi-filament yarns braided together in a diamond braid construction. The term "multi-filament" is being utilized in a comprehensive sense, and refers to the plurality of filaments employed in the preparation of the composite line structure. In order to enhance the flexibility of the composite product, and to enable splicing of the finished rope, it has been found desirable to add a quantity of relatively low modulus fibers, such as polypropylene to the core braid. The sheath construction is essentially a braid of multi-filament yarn of relatively low modulus but high abrasion resistant material, with the filaments forming the sheath material consisting of polypropylene. It will be appreciated, of course, that polyolefins may be employed for the sheath construction, with polyethylene being suited for application to the sheath.
In preparing a preferred composite structure with specific application to a ski-tow rope, the following yarns were employed:
1. 15 filament .007 polypropylene Denier - 3,600 Test - 40 lbs.2. 60 filament .007 polypropylene Denier - 14,400 Test - 160 lbs.3. 100 filament polyimide Denier - 1,500 Test - 65 lbs.
Each of these filamentary materials is commercially available, with the polypropylene material being widely available, and with the 100 filament polyimide yarn being available from E. I. DuPont de Nemours Corp., Wilmington, Delaware, under the code name "Kevlar DP-01." In order to fabricate this structure into a composite rope, the following operations are conducted.
CORE CONTRUCTION
One yarn of 15 filament 0.007 polypropylene and two yarns of 1500 denier polyimide are spooled together on braider bobbins. These yarns are then braided together in a diamond braid construction. The presence of polypropylene in the core renders it more easily spliceable, thus making a braided core that can be entered with a splicing fid. It has been found that the high modulus fibers of polyimide do not remain firmly in place, thus rendering the material difficult to treat with a splicing fid.
SHEATH CONSTRUCTION
Yarn comprising 60 filament 0.007 polypropylene fibers is braided over the core material. While other filament counts may be employed, it has been found that the specific combination herein provides the best results when employed on eight carrier braiders. The core is preferably passed upwardly through the center of the eight carrier braider whereupon the sheath is braided thereover.
PHYSICAL PROPERTIES
In the composite material provided, the following physical properties of components and composite are provided:
CorePicks per foot - 30Diameter - .150 inchesYield - .44 lbs. per 100 foot .21 lbs. propylene .23 lbs. KevlarTest - 820Elongation - 9.6%SheathPicks per foot - 30Yield - .66 lbs. per 100 footTest - 1,450Elongation - 22%Composite RopePicks per foot - 30Diameter - .300 inchYield - 1.1 lbs. per 100 foot .87 lbs. polypropylene .23 lbs. KevlarTest - 1,260Elongation - 9%
From this data, it is apparent that the physical properties of the composite exceed that of the sum of the components.
POLYIMIDE FIBERS
As has been indicated, the polyimide fibers are characterized by a structure having a repeating unit with the following structural formula: ##EQU2## wherein R is a tetravalent aromatic radical, and wherein R is a divalent benzenoid radical. Aromatic polyimides of this type and the process of preparing them are disclosed in U.S. Pat. No. 3,179,634, and reference is made to that patent for a disclosure of the process for preparing typical polyimides of this type.
ALTERNATE CONSTRUCTIONS
While it has been indicated that the core material be braided, it will be appreciated that the core may be prepared from fibers or yarns having generally parallel orientation, as well as twisted orientation. It will be appreciated, however, that the braided core will provide ideal peformance for water ski use. In the utilization of a twisted core, generally similar preparation techniques will be employed, with the exception of the formation of the twisted core.
As has been indicated, polyolefins are preferred for materials of construction for the fibers forming the sheath, and hence in lieu of the polypropylene employed in the specific example herein, polyethylene may be employed as a direct substitute for the polypropylene and in the same filamentary diameter.
As has been indicated, the term "multi-filament" has been utilized in a comprehensive sense, and thus it will be appreciated that the core may be prepared from woven multi-filaments, or alternatively from braided or twisted filaments generally known as "monofilaments" in the industry. It will be appreciated, therefore, that reference to the term "multi-filament" is not intended to limit or restrict such structures to those having a diameter of 0.003 inches or less.
Inasmuch as the densities may vary from yarn to yarn the ratio of materials utilized in the preparation of the composite structure may be modified or selected so as to achieve a specific gravity within any desired useful range. For water ski tow ropes, of course, a specific gravity of less than 1 is desired in order to assure a floating line.
WATER SKI-TOW APPLICATION
In a water ski-tow application, the rope has high strength, low elongation or stretch, and high abrasion resistance. Under typical water skiing conditions, the load applied to the rope varies significantly from time to time, particularly when the skier is engaged in a slalom event. If the rope has relatively high elongation or stretch, the performance of the skier may be compromised due to the slower response of the tow rope. With the lower stretch material of the present invention, the response time is significantly shortened and the skier may perform unusual movements with a greater degree of predictability and more uniform response. | A multi-filament rope which comprises a blend of filaments braided together to form a composite line structure. The core of the structure consists primarily of polyimide of an aromatic tetracarboxylic acid dianhydride, with the sheath consisting primarily of polyolefin fibers selected from the group consisting of polypropylene and polyethylene braided over the core. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of, and priority to, U.S. Provisional Application Ser. No. 61/592,494 filed on Jan. 30, 2012, entitled “A means for attaching Split-board specific bindings or sliding rail bindings to non-split-board or regular snowboard,” which is incorporated herein by reference in its entirety.
REFERENCES CITED
[0002]
[0000]
Cited
Original
Patent
Filing date
Issue Date
Assignee
Title
5,984,324
Aug. 14, 1997
Nov. 16, 1999
Voile Man-
Touring
ufacturing
Snowboard
8,226,109
Jun. 11, 2009
Jul. 24, 2012
Splitboard
Bindings
BACKGROUND OF THE INVENTION
[0003] Most snowboarding occurs within the monitored boundaries of a ski resort. Often snowboarders own several snowboards, each with slightly different shapes, camber, and/or varying levels of stiffness, for use in different snow conditions and territory on the mountain. A growing population of snowboarders also own a splitboard and splitboard bindings such as but not limited to those disclosed in U.S. Pat. No. 5,984,324 (Wariakois) and U.S. Pat. No. 20120256395 (Ritter) respectively. A splitboard as disclosed in U.S. Pat. No. 5,984,324 (hereby incorporated in full by reference) is comprised of a pair of “skis” (two halves of a snowboard) that may conjoin via hooks or latches to form what looks like and functions as a snowboard. Wariakois' splitboard design is centered around the idea of allowing one to approach and climb a slope on two “skis”, and consequently descend that slope via snowboard configuration, with “skis” latched or hooked together. As Ritter points out, “Backcountry splitboarding, which combines ski touring and snowboarding, thus requires boot bindings adaptable for both ski configuration (i.e. one to a ski) and for snowboard configuration, (i.e. joining the skis as a snowboard)” (U.S. Pat. No. 20120256395). As such, backcountry splitboarding also requires binding mounts for both ski configuration and snowboard configuration. Ski configuration binding mounts would run parallel to the individual ski members, whereas, snowboard configuration binding mounts would run at an adjustable angle, each foot across both ski members (traditional snowboarding stance.) For the purposes of the present invention, only the binding mounts for snowboard configuration are relevant and below-mentioned.
[0004] Wariakois' binding, according to Ritter per U.S. Pat. No. 20120256395, employs “one widely used configuration of the prior art [in which] mounting block assemblies are attached in pairs crosswise on the opposing ski member halves of the splitboard, one pair for the forward leg and one pair for the back leg. These mounting blocks, disclosed by Wariakois in U.S. Pat. No. 5,984,324 (hereby incorporated in full by reference) include a toe mounting block and a heel mounting block, which are designed to slidingly receive an adaptor mounting plate . . . .” These prior art mounting blocks' are structurally designed with hole patterns, by which they are affixed to Wariakois' splitboard or any other industry standard splitboard. Splitboard hole patterns are wider (at 85 mm by 25 mm) than a snowboard's (at 40 mm by 20 mm, 20 mm by 20 mm, both industry standards), making these mounting blocks unable to affix to a snowboard.
[0005] Per U.S. Pat. No. 20120256395, Ritter designed new bindings to fit Wariakois' mounting block design. Rather than needing an additional adaptor plate, Ritter's bindings slide directly onto Wariakois' mounting blocks.
[0006] The present invention provides a receiver plate and receiver plate retainer that slidingly accept Ritter's splitboard binding or the likes thereof as laid out in U.S. Pat. No. 20120256395. Ritter's splitboard binding is structurally superior to prior art, and the present invention herein stated now allows Ritter's bindings to be affixed not only to splitboards but also to snowboards. The option of mounting a traditional snowboard with splitboard or slide-mount bindings does not exist in prior art.
[0007] The present invention allows snowboarders to use a slide on and off binding for splitboards on snowboards as well. Snowboarders can own one set of bindings and multiple boards with the present invention affixed to each board. Each system on each board has a set stance, angularly determined, that the rider may take advantage of easily, switching the bindings from board to board quickly. Thus, on a powder day, a rider may switch his bindings onto the board he prefers for deeper snow that already has his stance in place. He need not adjust the stance each time he switches boards.
[0008] The dimensions and sizing to fit a splitboard are an extreme limiting factor in providing a way to firmly mount a splitboard binding onto a traditional snowboard and still allow for adjustability of the angles while making a product strong enough for the rigors of riding. Given the amount of different snowboards and different bindings, it is not easy to change bindings between the various types of snowboards, and usually bindings are specific to boards or vice versa. This can make it very difficult to change bindings from board to board let alone the hassle of switching screws, screwing and unscrewing, and adjusting the angles of the various boards one might own. The end result of the present invention is that any board can now be used at any time, for changing conditions or preferences with a single pair of splitboard or slide-mount bindings.
[0009] Many other binding systems use different holes, disks, or tracks to attach said bindings to a board; these various systems make it impossible to own multiple boards and use the same binding. Thus the present invention solves the problem of having to buy multiple sets of bindings for multiple boards. It makes stance adjustments simple and switching bindings between boards even simpler.
BRIEF SUMMARY OF THE INVENTION
[0010] Disclosed here are mounting plates for attaching splitboard bindings to a snowboard. Contrary to presented teachings herein, teachings of the prior art disclose a series of mounting blocks designated for use on a splitboard with no prior art or solutions in disclosing the ability or option to use mounting plates for the purpose of riding on a snowboard. The object of the present invention is to make mountable a pair of splitboard bindings, which use a box girder type construction, variform box girder construction, or any similar means of a mediolateral flange attachment, to slidingly be placed on a snowboard as defined herein. No solution has been offered in the prior art to accomplish this, as mounting points are different on a snowboard comparatively to a splitboard. As previously defined, a snowboard is comprised of one solidly laminated piece that is inseparable. Due to the narrower hole patterns of a snowboard, there are many constraints in size and strength that must be overcome in order to mount splitboard bindings to a snowboard. The receiver plate and receiver plate retainer interface design allows for the weight of a snowboarder, translated through his bindings, to be distributed effectively from edge to edge of the snowboard, regardless of the narrower hole pattern. It provides a strong solution over the now longer area it must cover with minimal bolts while still functioning effectively over a wider-spanning distance.
[0011] The receiver plate and receiver plate retainer interface provides adequate support to keep a splitboard binding firmly attached to a snowboard. By making the receiver plate retainer of an oblong shape, the receiver plate can be oriented angularly according to a rider's stance while still fitting a splitboard binding. The receiver plate retainer disperses and channels forces to the edges of the snowboard resulting in a strong receiver plate and receiver plate retainer assembly, also allowing quick edge-to-edge response of the snowboard. In function, by resting the receiver plate retainer in the aligned groves, notches, or ridges within the receiver plate at a user-defined angle, the tightening force on the receiver plate retainer sandwiches the receiver plate in the correct and chosen orientation as to provide a seamless and attached assembly to the board granting the user an easy on/off procedure of the splitboard binding. Thus creating a riding interface not seen before in snowboarding history.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0012] These teachings of the invention can be easily understood whilst considering the following detailed descriptions along with the drawings and claims, in which:
[0013] FIG. 1 is an exploded view of a receiver plate retainer and receiver plate as forming the assembly.
[0014] FIG. 2 is a perspective view of a snowboard mounted with receiver plate retainer and receiver plate.
[0015] FIG. 3 is a perspective view of a receiver plate retainer.
[0016] FIG. 4 is a perspective view of a receiver plate.
[0017] FIG. 5 is perspective view of a receiver plate using an alternative groove or notch type adjustment.
[0018] FIG. 6 is a perspective view of a receiver plate retainer using an alternative groove or notch type adjustment.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The terms below-mentioned are defined herein as intended by the inventor, i.e., they are inherent meanings Any cited works incorporated by reference that utilize any meaning or definition of a word in the reference that diminishes or conflicts with the meaning as used here shall be considered idiosyncratic to said reference and shall not supersede the meaning of the word as used in the disclosure herein.
1. DEFINITIONS
[0020] Snowboard: a single, inseparable, and laminated board intended to slide downhill on the snow, using standard 4×4 4×2 or slot mounting hardware.
[0021] Splitboard: A pair of two separable ski members that join together using hardware and retention clips to take the form of a snowboard.
[0022] Splitboard bindings: Consists of a pair: one for each foot of a snowboard rider. Comprised of metal or thermo-moldable plastics. Any type of snowboard bindings, which use a box girder type construction, variform box girder construction, or any similar means of a mediolateral flange attachment, to slidingly be placed on a snowboard as defined herein.
[0023] Receiver Plate Retainer: Center fastening piece in which 4 or 2 bolts are placed through and connected to standard snowboard mounting features. Comprised of metal or composite thermo-moldable plastics. Securely retains the receiver plate at a specified angle for a rider's stance.
[0024] Receiver Plate: rotationally coupled to the receiver plate retainer. Rotates around receiver plate retainer so that a given angle that corresponds to the grooves, notches, or slots can be chosen before the receiver plate retainer is fully tightened to the snowboard.
[0025] Rider: One who rides or uses a snowboard to enjoy the thrill of going through and down the snow, also requiring a specific stance or stance angle coordinated by using the mounting points of a snowboard to make one's stance angles correct and optimal.
[0026] Hardware: standard mounting hardware for snowboard bindings typically of an M6 style bolt supplied with snowboards or traditional snowboard bindings; used to fasten bindings to a snowboard.
[0027] Mounting Point/Insert: exists on both splitboards and snowboards and allows for a screw to be mounted, attaching hardware for the fastening of bindings onto a board. Splitboard and snowboard mounting points are uniquely different due to the inherent differences in binding types and mounting preferences associated with snowboarding and splitboarding.
2. DETAILED DESCRIPTION
[0028] Referring now to FIG. 1 , this exploded view of the receiver plate retainer ( 1 ) and receiver plate ( 2 ) shows the assembly when using standard hardware to conjoin the two parts for a rider's chosen alignment: as seen mounted to a snowboard's insert ( 3 — FIG. 2 ). Commonly, snowboards have bindings that mount to them using inserted attachment points or anchors ( 3 — FIG. 2 ) and usually this is in a 20×40 mm configuration or by means of a track mount. Using the holes ( 5 — FIG. 6 ) in the receiver plate retainer ( 1 ), one must insert screws through the holes ( 5 — FIG. 6 ) in the receiver plate retainer. Mounts/inserts on a snowboard ( 3 — FIG. 2 ) differ from those on splitboards (see prior art U.S. Pat. No. 5,984,324). Splitboards use a common mounting block as per U.S. Pat. No. 5,984,324. Given the nature and proprietary features of a splitboard under U.S. Pat. No. 5,984,324, splitboard mounting blocks were not designed for nor are capable of mounting to a snowboard. This due to the fact that all splitboards use proprietary mounting configurations as per U.S. Pat. No. 5,984,324. These patterns restrict angular adjustability on any common variations of the mounting blocks and these blocks are further impeded by their lack of strength to span the greater distances in insert patterns seen on a snowboard. New shapes and different materials must be chosen to ensure the ability to fasten a splitboard binding to a snowboard given these above listed constraints.
[0029] The invention differs from many other board to binding interfaces in that the receiver plate retainer and receiver plate use a specifically shaped, molded or milled assembly to allow for bindings (currently made solely for splitboarding) to be attached to any standard non-split snowboard. Furthermore this specifically shaped assembly allows splitboard or box girder type bindings to be slidingly received by the assembly while allowing freedom of stance options limited to 40 degrees.
[0030] The receiver plate retainer ( 1 ) is specifically shaped to use the reach of an oblong type shape to create the maximum surface for retaining the maximum surface area and attain a degree of adjustment equal to or less than 40-degrees. The stronger receiver plate retainer ( 1 ) is therefore able to extend the flex and structural aspects of the receiver plate ( 2 ) to allow for maximum distribution of the side to side flexes and stresses associated with maneuvering a snowboard.
[0031] Relationship Between the Components:
[0032] The receiver plate retainer ( 1 ) is mounted by means of mounting hardware through the receiver plate ( 2 ) onto the snowboard using 4 or 2 screws that go through the holes ( 5 ) in the receiver plate retainer ( 1 ) and fasten the whole assembly ( 9 ) to the snowboard's mounting points ( 3 — FIG. 2 ), holding the receiver plate retainer ( 1 ) against and down on the receiver plate ( 2 ) as to make the receiver plate retainer ( 1 ) and receiver plate ( 2 ) pieces conjoin along the grooves, notches, or teeth ( 6 — FIG. 3 , 10 — FIG. 4 , 7 — FIG. 5 , 8 — FIG. 6 ) at a determined angle to a rider's stance preference and hold the tightened assembly ( 9 ) to the board with common and standard hardware provided by board and binding makers.
[0033] How the Invention Works:
[0034] The receiver plate retainer ( 1 ) and receiver plate ( 2 ) components work together to create a mounting surface for a splitboard or box girder type binding. The receiver plate retainer ( 1 ) attaches through the receiver plate ( 2 ) by using screws standard for mounting a snowboard. The receiver plate retainer ( 1 ), and receiver plate ( 2 ) matingly engage together, via corresponding grooves, notches, or teeth ( 6 — FIG. 3 , 10 — FIG. 4 , 7 — FIG. 5 , 8 — FIG. 6 ) and allow the receiver plate ( 2 ) to stay fixed in a chosen orientation to the snowboard as retained by the mounting inserts in a snowboard ( 3 — FIG. 2 ). The receiver plate ( 2 ) rotates around the receiver plate retainer ( 1 ), allowing the stance to be adjusted only when the receiver plate retainer is loosened for that purpose, as once the receiver plate retainer ( 1 ) is fully tightened, further rotation becomes impossible due to the effect of the downward forces on the matingly engaged parts of the assembly ( 6 — FIG. 3 , 10 — FIG. 4 , 7 — FIG. 5 , 8 — FIG. 6 ). Once a given stance angle is chosen and mounting hardware is tightened the splitboard binding can be slidingly received by the assembly ( 9 — FIG. 2 ).
[0035] How to Make the Invention:
[0036] The invention would be made by either milling, stamping, or molding the two pieces, receiver plate retainer ( 1 ) and receiver plate ( 2 ), from metal or thermo-moldable plastics. The parts expressed as the receiver plate retainer ( 1 ) and the receiver plate ( 2 ) are necessary to make a splitboard binding mount to a snowboard. The size of the receiver plate retainer ( 1 ) can be changed to make a smaller or larger interface; whereas, the shape of the receiver plate ( 2 ) must remain constant due to the constraints of splitboard or box girder type binding dimensions. The shape of the receiver plate retainer ( 1 ), could be altered to allow either a smaller or larger size, could be different shapes or materials as to allow for different stance options or a stronger connection. The receiver plate retainer ( 1 ) could also have different hole configurations to allow different mounting options for new or different, emerging snowboard mounting technologies. The receiver plate ( 2 ) can be adjusted to shave weight, harden material, or change the overall flex on a snowboard. The receiver plate ( 2 ) can be made of different combined materials to allow for a more flexible interface with a snowboard.
[0037] How to Use the Invention:
[0038] A person who has a set of splitboard bindings or slide-mount bindings made by various manufacturers would purchase a mounting system comprised of receiver plate retainers ( 1 ), receiver plates ( 2 ), and associated hardware. He would then affix these assemblies to his snowboard, allowing him to put his splitboard bindings on a snowboard aside from his splitboard, effectually buying one pair of bindings for multiple boards and allowing splitboard bindings to be mounted on all snowboards whether or not their snowboards have different hole patterns, tracks, etc.
[0039] Additionally: The combination of the receiver plate retainer ( 1 ), and receiver plate ( 2 ), allows for various other attachments to be connected to a snowboard such as but not limited to a lock, larger no bindings, no boarding plates, tool assemblies, or padding not limited to rubber inserts that may be added under the plate, changing desired flex of the overall unit or maintaining a solid grip to board interface. Furthermore, dimensions of the hole patterns in which the mounting hardware is placed in the receiver plate retainer ( 1 ) can be changed to fit various hole patterns or alternate hardware preferences.
[0040] Herein as stated, the preferred embodiment visually shown and described is capable of achieving the objective in relation to the present invention. These embodiments are described and shown only for the purpose of the illustration and not for the purpose of limitation; those skilled in the art will appreciate that many additions, modifications, and substitutions are possible without departing from the scope of the invention as defined herein. | Mounting system for attaching splitboard bindings or slide-mount bindings to non-splitboards or snowboards as to use multiple boards with one set of bindings, or interchange bindings quickly. Accomplished by using an assembly comprised of two congruent parts, namely a receiver plate and receiver plate retainer, that affix to a snowboard to allow the above mentioned bindings to slide on and off of any snowboard mounted with said assembly. A receiver plate retainer rests in and atop a notched and patterned receiver plate that, when fastened, creates a solid but angularly adjustable mounting system for said bindings to be securely fastened to a standard snowboard. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The instant invention relates to hot-gas solder levelling machines, and more particularly to a pneumatic system for controllably lowering a printed circuit board into a pool of molten solder, stroking the board upwardly and downwardly while immersed and subsequently raising the board out of the bath past a pair of knives from which a hot gas is directed upon the board to control the thickness of solder on the circuit conductors and the like of the board and to clear the through-holes of excess solder.
2. Description of the Prior Art
In the past, various techniques have been used to remove excess solder from printed circuit boards and to clear the through-holes of excess solder. One such prior art technique involved spraying or otherwise contacting the board with molten solder and subsequently immersing the board in a pool of hot wax or oil, vibrating the board to remove the excess solder and clear the holes and then withdrawing the board to cool. This technique had associated with it certain problems relating to pollution from fumes from the hot wax or oil and thermal shock to the boards which caused the printed circuits to lose continuity in some connections.
Another prior art technique involved immersing a board in molten solder and subsequently exposing the board to a blast of hot air or other gas. This technique has proved more effective than the hot wax or oil technique, but prior art machines for accomplishing the technique were generally slow and difficult to adjust for consistent and controllably variable solder deposition thicknesses.
SUMMARY OF THE INVENTION
The instant invention overcomes the problem of the prior art systems by providing a pneumatic arrangement for easily varying the rate of insertion and removal of the board from the molten solder and the length of insertion time within the solder. A pneumatic system in accordance with the invention comprises an air cylinder arrangement to insert and remove the board and a pulsing system for pulsing the board while immersed in molten solder at the bottom of the immersion stroke to agitate the board.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a solder leveling machine embodying features of the invention.
FIG. 2 is a side view of the machine of FIG. 1.
FIG. 3 is a schematic diagram of a pneumatic system usable with the machine of FIG. 1.
FIGS. 4 and 5 are side and perspective views, respectively, of a solder pot and sump according to the invention.
FIG. 6 is a partial schematic diagram of the hot air system of the invention.
FIG. 7 is a view of a manifold for the air knives of the invention.
FIGS. 8 and 9 are partially sectioned views of the air knives of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a front view of a machine incorporating the features of the instant invention. It should be understood that the actual machine would be preferably enclosed in a heat-retaining protective cabinet, which is not illustrated for purposes of clarity.
A solder pot 2 is shown into which a printed circuit board 4 is to be lowered. The printed circuit board is secured by a fixture 6 which is clamped to a movable member 8 which moves along a guide rod 10 to lower the board into the solder pot 2. An air knife 12 is shown, the air knife being one of a pair of air knives, in front of and behind the path of the printed circuit board 4.
Also shown in FIG. 1 is a hand-operated switch 3 for operating the machine. Obviously other switches, such as automatic switches or foot switches may be used. The connection and function of the switch will be described in connection with the description of the operation of the pneumatic system of the machine.
FIG. 2 shows a side view of the machine of FIG. 1 with like parts having like numbers. The rear air knife 14 is observable in FIG. 2. Further shown in FIG. 2 is another rod 11 attached to the piston of an air cylinder 13 upon which the movable member 8 travels in lowering the board into the solder pot. Movable member 8 extends through the support to the rear of the support through a slot 9 only the bottom of which is visible in FIG. 1.
At each end of the air knives is a manifold 16 and 18, each manifold being connected to a source of hot air or other gas under pressure 20 and 22.
To the immediate left of the solder pot is a solder reservoir 24 into which extends a submersible pump 26. The pump is driven by a pulley 28 by means of a motor mechanism not shown. Associated with the solder pot is a spillway 30 which openly communicates with the solder reservoir at 32. Partially hidden in FIG. 1 behind the solder pot 2 are a pair of heaters 34 and 36, each of the heaters having an outlet through the pipes 20 and 22 connecting the air or gas heater to the air knife manifolds 16 and 18.
Shown in FIG. 2, is a conduit 38 through which solder in the reservoir 24 may be pumped by the pump 26 into the solder pot 2.
A plurality of heaters, which may be strip heaters bolted to the sides of the reservoir or pump 24 and solder pot 2, are not illustrated for purposes of clarity.
Also shown in FIG. 2 are air switches 5, 7, on a suitable mounting bracket, the operation and function of which will be explained in connection with the description of the operation of the pneumatic system of the machine which follows.
FIG. 3 is a schematic diagram of a pneumatic board raising and lowering system showing the appropriate controls and valves to cause the movable member 8 of FIGS. 1 and 2 to lower the printed circuit board 4 into the solder pot 2. While the board is immersed within the solder which is kept at a level at the top of the solder pot, the pneumatic mechanism may pulse the board rapidly up and down over a relatively short stroke to agitate the board while immersed within the molten solder of the solder pot 2.
The hand valve 3 is shown having a connection to a main supply of air. The hand valve 3 has an output connected by a line to a Tee connection 39. Tee 39 is in turn connected to a pulse valve 40 and the upper air switch 5, shown in FIG. 2. The air switch 5 is connected to one side of shuttle valve 41, the other side of which is connected to pulse valve 40. The outlet of shuttle valve 41 is connected to a master valve 42. Master valve 42 is connected to the main air supply source at 49 and has two outlets, one directed to flow control valve 43 and the other to flow control valve 44. The outlet of flow control valve 43 is connected to the top of air cylinder 13, and thus is the flow control valve which controls the rate of descent of the printed circuit board into the solder pot. The output of flow control valve 44 is connected to the bottom of air cylinder 13 and controls the rate of withdrawal of the board from the solder pot.
A second air switch 7 is connected to the main air source and also to a second shuttle valve 45. Shuttle valve 45 is connected to master valve 42 and to a pulse valve 46 which in turn is connected to a second outlet of hand switch 3. Master valve 42 has an exhaust mechanism 48, a part of the valve which acts to release air pressure applied to the piston of air cylinder 13 upon reversals of applied pressure to the piston.
Before the hand valve 3 is operated, no air except the main air supply source at 49 enters the master valve. This set of circumstances causes the master valve to direct the main air at 49 to the bottom of the piston of air cylinder 13 via the flow regulator 44 to withdraw the board from the solder pot.
The shuttle valves 41 and 45 normally prevent flow from pulse valves 40 and 46 to master valve 42. When hand valve 3 is operated, a flow of air from the main air supply and through valve 3 is applied to pulse valves 40 and 46 and, through Tee 39 to air switch 5. The application of air to pulse valve 40 opens shuttle valve 41 such that air flows from pulse valve 40 into master valve 42. Master valve 42 directs the main air supply source to flow regulator 43 which, in turn, applies air pressure to the top of air cylinder 13 causing the piston therein to begin a downstroke lowering the printed circuit board into the solder pot.
As the piston descends, and carries movable member 8 downwardly, member 8 strikes air switch 7. When switch 7 is tripped, the main air supply is momentarily connected, through switch 7 to shuttle valve 45 which operates to allow the source air switch to flow to master valve 42 and thereby cause it to change state. Master valve 42 exhausts the air pressure to the top of cylinder 13 and applies an air flow from the source supply to flow regulator 44 which applies air pressure to the bottom of the piston of air cylinder 13 to start the piston upward. Flow regulator 44 regulates the rate of withdrawal of the board from the solder pot to aid in controlling thickness of deposition of solder.
In this case, since hand valve 3 is still being held down, the board is not withdrawn but the up-stroke is stopped by the tripping of air switch 5. The tripping of air switch 5 allows source air pressure from Tee 39 to be applied momentarily to shuttle valve 41 which reverses its position and allows the flow of source air to master valve 42 again changing the state of that valve. Again, cylinder air pressure is exhausted and air flow is applied from the main air supply through regulator 43 to the top of the piston of cylinder 13 as in the initiation of operation.
The ensuring down stroke again trips switch 7 starting another up stroke. When switch 7 is tripped the momentary application of source air from switch 7 reverses master valve 42 as before. It may be noted that at all times during which hand switch 3 is depressed pulse valves 40 and 46 tend to bias the shuttle valves in the direction indicated by the arrows associated therewith.
The pulsing action continues as previously described until hand valve 3 is released. On the next upstroke following release of valve 3, switch 5 can no longer reverse the master valve 42 since its source of air passes through valve 3. The upstroke continues past switch 5 until the uppermost or home position is reached. The cycle may be repeated by again depressing hand valve 3.
During the pulsing action the stroke is limited, as previously noted, such that the printed circuit board does not emerge from the molten solder. The stroking then serves the purpose of agitating the solder pool and helping to control the thickness of solder coating on the board.
FIG. 4 is a side view of the solder pot 2 and solder sump 24 and FIG. 5 is a perspective view of the same elements. The pump 26 is not shown in either of the figures so that other details of the structure are visible.
For purposes of illustration, the solder pot of the instant invention may have an internal width of approximately two inches, a height of approximately 24 inches, and a length of approximately 28 inches. The solder sump 24 may have a width of approximately six and one-half inches, a height of approximately twelve and three-quarter inches and a depth of approximately twelve and three-quarter inches.
As can be seen in FIGS. 4 and 5, a pool of solder fills sump 24. By means of the pump 26 and the pipe or conduit 38 associated therewith, solder is pumped from the sump to the bottom of the solder pot 2. As the solder is pumped into solder pot 2, the level of the solder ultimately reaches a rim near the top of the solder pot shown at 50 which is slightly lower than the actual top of the solder pot. As solder is continually pumped into the solder pot, solder overflows at the lip 50 into a channel 52. The channel 52 allows the overflowing solder to spill back into the solder sump 24. This action carries any dross which may have formed on the top of the solder pool off into the sump from which it may be conveniently skimmed, by means not shown, without interfering with the operation of the solder levelling machine, and particularly with the action of the printed circuit board 4 being lowered into and removed from the solder pot 2.
Since the level of the solder pot is higher than the level of the sump to allow the dross to run from the solder pot into the sump, in the event of a machine shutdown, and termination of operation of the pump, solder will tend to be drawn back into the sump by a siphon action and ultimately overflow. To prevent the overflow of solder from the sump when the machine is inoperative, an antisiphon valve 54 is provided in the conduit 38 to break the suction and prevent overflow spillage.
In addition to the self-purging features described above, it may be noted that the solder is pumped from the sump into the solder pot at the bottom of the solder pot. This provides a continuous flow of solder through the solder pot such that the entire pot stays hot at a relatively constant temperature, slightly above the melting temperature of solder. With a static pot, as has been used in the past, the top of the solder tends to become chilled due to the lowering of relatively cool printed circuit boards into the solder. The solder pot of the instant machine, therefore, provides automatic skimming to remove slag, dross, and contaminents at the top of the solder pot and also provides a uniform temperature throughout the depth of the solder pot.
FIG. 6 is a partially schematic diagram showing the air knives 12 and 14 between which a printed circuit board passes upon being raised from the molten solder bath and solder pot 2. The air knives provide a blast of air or other hot gas to remove excess solder from the printed circuit board and to clear the molten solder from the through-holes of the circuit board.
In conjunction with FIG. 6, it is useful to consider FIGS. 7, 8, and 9. As before, like parts will be provided with like numbers.
At either end of the air knives 12, 14, are manifolds 16 and 18 through which heated air, under pressure, is introduced into the air knives 12, 14. Each manifold has associated therewith a heater 34, 36 which communicates with the manifold through an inlet hole 60. The manifold allows flow of air to enter the air knives 12, 14 through conduits 62, 64.
The heaters 34 and 36 may be any heater means for storing a quantity of air and heating the air to a suitable temperature, somewhat above the temperature of molten solder.
Air is directed to the heaters 34 and 36 through conduits 66. Pressure regulators 68 are provided in the line together with solenoid valves 70 to turn on and turn off the flow of air from the air supply indicated at 72 to the air knives. In operation, as a circuit board is being removed from the solder bath 2 to pass between the air knives 12 and 14 a blast of heater air or other gas is allowed to flow by means of operation of the solenoids 70 to connect the air supply to the heaters. The solenoids are actuated by connections, not shown, from switches 76, 78 which, in turn, are actuated by movable member 8 as the board is withdrawn from the solder pot. Switch 76 is actuated to turn on the blast of air and switch 78 turns the blast off.
FIG. 8 is a front view of air knife 12. The air knife 12 has a central cavity 70 into which air flows from the manifolds 16, 18. As the air flows under pressure from the heater air supply to the air knife, the air is forced through the slot in the front of the air knife 72 which slot may be approximately 20/1000th of an inch wide. Merely for purpose of reference, the width of the knives may be on the order of 24 inches. This width is not critical, and may be any convenient width desired to handle circuit boards of a desired size. Mounted on the bottom segment of each air knife are five spacers 74, which spacers are approximately 20/1000th of an inch in height. The spacers are somewhat recessed from the aperture of the air knife so that turbulence in the operation area of air knives is eliminated. It has been found, however, that while baffling is not necessary with the double manifold arrangement of the instant device, the spacers do help to provide an even flow of air across the relatively long width of the knives and improve operation of the device. As the knives are heated by the hot air, any temperature variation across the width of the knives may result in a twisting and a distortion of the aperture shape and size. The spacers retain the correct aperture size. It should be further noted, that since no baffling is present within the air knives, a relatively equal pressure should be applied to each of the manifolds 16, 18 by means of the pressure regulator 68 in the air supply lines.
In operation, a printed circuit board 4 is attached to a holding mechanism 6 which is mounted on a movable device 8 which is pneumatically operated to lower the printed circuit board 4 into the solder pot 2 which is filled with molten solder. When the printed circuit board 4 reaches the bottom of the lowering cycle, the board may be stroked, or moved upwardly and downwardly for a short distance while remaining immersed, a variable number of times in order to agitate the flowing solder and to vary the subsequent thickness of the solder which will adhere to the exposed conductors and through-holes of the circuit board. Upon completion of the stroking action, the board is raised between a pair of air knives 12, 14. As the board is passing between the air knives, a blast of hot air or other gas (such as an inert gas to reduce the occurrence of dross and slag on top of the solder pot) impinges upon the both sides of the circuit board to remove the excess solder from the board and to clear the molten solder from the through-holes which are provided in the circuit board. The air flow continues until the board has traveled beyond the limit of the air knives. The air knives may be actuated at an appropriate time by means of solenoid valves 70 which connect the air knives, through a heating device, to an air supply. (It should be noted, that prior to immersing the board in the molten solder, the board is suitable prepared for soldering by washing or scrubbing, possibly etching with a mild acid solution, and thoroughly fluxing such that solder will be more readily accepted). The pressure of the gas may be varied to vary the thickness of the solder remaining on the board. The thickness of the solder may also be varied by varying the rate of withdrawal of the board from the solder pot.
Continually, during the process, a supply of molten solder is provided from a solder sump 24 by means of a pump 26 through a conduit 38 to the bottom of the solder pot. Since a fresh supply of molten solder is continually provided at the bottom of the solder pot, the solder continually flows upwardly through the solder pot to aid in maintaining a uniform temperature throughout the solder pot. The excess solder from the pumping action overflows at the top of the solder pot and is directed back to the sump together with slag dross, and impurities. The slag, dross and impurities may be removed from the sump by appropriate skimming means. As previously noted, an antisiphon valve 54 may be provided in the conduit 38 to prevent siphoning action which may overflow the solder sump in the event the machine is shut down while the solder is still in its molten state.
After the printed circuit board has been coated with solder and leveled it may be cleaned and treated in an appropriate manner to prepare the board for application of components thereto.
While the invention has been described with respect to a specific embodiment thereof, it is understood that alternatives may occur to those skilled in the art. The invention, therefore, should be limited only by the scope of the claims appended hereto. | A solder levelling machine which uses a hot gas emanating from opposed gas knives to remove excess molten solder from a printed circuit board as the board is withdrawn from a bath of molten solder contained in a self-purging solder pot. The hot gas clears the through-holes in the circuit board and allows a controllable desired thickness of solder to remain on the board and in the through holes. A pair of heaters supplies the hot gas to the knives through a manifolding arrangement. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a louvered arch mechanism, and more particularly, to a louvered arch window that includes a mechanism for opening and closing blinds that are radially disposed with a common central point.
2. Description of the Related Art
Many designs for louvered arch mechanisms have been designed in the past. These mechanisms are used in arches that are typically positioned above doors and windows. None of them, however, has the blinds taut at one end while the other end (distal end) is actuated (rotated) in tandem with a common link. The blinds or louvers or slats are remotely rotated by a user. The actuating mechanism has the advantage of being substantially flush with the arched member.
Applicant believes that the closest reference corresponds to U.S. Pat. No. 1,447,189 issued to Simon on Mar. 6, 1923. Simon's patented invention includes a frame assembly ( 1 ) with horizontal piece ( 2 ) and semi-circular or arcuated pieces ( 3 and 4 ), slats ( 5 ) with wire framework ( 10 ), block ( 11 ) and arcuated (actuating) member ( 19 ) with the consequently structural exposure. The ends ( 12 and 13 ) of framework ( 10 ) are mounted to lower arcuated piece ( 4 ). However, it differs from the present invention because the distal end of the blinds is actuated with a common link connected to a gear assembly mounted to the center of the distal end. In Simon's, the slats ( 5 ) are pivotally mounted to a fixed concentric member (arcuated piece 3 ) and the distal ends of the blinds are actuated with arcuated members ( 19 ) connected to one of the external edges of the distal ends of slats ( 5 ), not in the central axis of the pivot point. There is no mechanism for aligning the slats or louvers as in the invention claimed herein.
Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.
SUMMARY OF THE INVENTION
It is one of the main objects of the present invention to provide a louvered arch mechanism where the louvers are remotely actuated and rotated between two extreme positions.
It is another object of this invention to provide a system is volumetrically efficient and thus capable of being mounted with minimum requirements.
It is still another object of the present invention to provide a system that imparts the rotational movement to the clips centrally mounted to the distal ends of the louvers at the center allowing the mechanism to be hidden.
It is yet another object of this invention to provide such a device that is inexpensive to manufacture and maintain while retaining its effectiveness.
Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which:
FIG. 1 represents an isometric view of one of the preferred embodiments for the louvered arch mechanism, object of the present invention.
FIG. 2 shows the louvered arch mechanism shown in FIG. 1, seen from the other side.
FIG. 3 illustrates a broken, detailed and partial view of one of the louvers used in the embodiment shown in previous figures for louvered arch mechanism.
FIG. 4 is a cross-sectional view taken along line 4 — 4 in FIG. 3 .
FIG. 5 shows an exploded view of the sprocket assembly used for the embodiment represented in FIGS. 1 through 4.
FIG. 6 represents an isometric view of another preferred embodiment for the louvered arch mechanism object of this application.
FIG. 7 illustrates a broken detail view of the embodiment shown in FIG. 6 for louvered arch mechanism with non-perfect or imperfect arch.
FIG. 8 shows an exploded view of the sprocket assembly used for the embodiment represented in FIGS. 6 and 7.
FIG. 9 is a cross-sectional view taken along line 9 — 9 in FIG. 7 .
FIG. 10 represent an isometric view of the washer member used in the present invention to avoid the frictional forces of the actuating mechanism assembly and the chain against the shoulder.
FIG. 11 represent a schematic view of the embodiment represented in FIGS. 6 and 7 for mechanisms with non-perfect or imperfect arch.
FIG. 12 shows an enlarged detail view of the sprocket assembly for the embodiment represented in FIGS. 6 and 7 for louvered arch mechanisms with non-perfect or imperfect arch.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, where the present invention is generally referred to with numeral 10 , it can be observed that it basically includes arched frame assembly 20 , blinds or louver members 30 , actuating mechanism assembly 40 and tensioning assembly 50 .
Frame assembly 20 includes arched frame member 22 and straight frame member 26 . Member 22 extends from one end of member 26 and joins the other end of member 26 . Arched anchorage member 28 is centrally mounted on member 26 , as seen in FIG. 2, extending at a parallel and spaced apart relationship with respect to member 22 and also in a substantially concentric relationship thereto. Arched back member 22 ′ serves as support for decoration arched cover member 22 ″. Member 22 ′ is perpendicularly mounted to member 22 ″. Member 22 ′ includes a number of recessed through openings 23 .
Blinds or louver members 30 include distal end 32 with through opening 33 at a predetermined distance from end 32 and proximal end 34 with through opening 35 at a predetermined distance from end 34 , as seen in FIGS. 3 and 4. Blinds or louver members 30 have a substantially truncated triangular shape and preferably are made out of a rigid material.
In the preferred embodiment, tensioning assembly 50 includes several anchoring members 54 mounted to member 28 . Flexible member 52 is preferably a chain, hooked at end 55 to opening 35 through hook 53 . Anchoring member 54 engages flexible member 52 between ends 55 and 55 ′ urging it away from member 22 ′ and keeping it tense.
In the preferred embodiment, actuating mechanism assembly 40 includes sprocket assembly 40 ′, pin members 48 , chain 60 , cable 61 , hook members 64 and actuating lever 62 , as seen in FIGS. 3, 4 and 5 . Sprocket assembly 40 ′ has upper and lower ends and includes sprocket member 42 with built-in washer 41 rigidly mounted to the lower end of sprocket assembly 40 ′, as best seen in FIG. 5 . Built-in washer 41 rests on washer member 45 and the latter rests on counterbore shoulder 25 permitting sprocket assembly 40 ′ to slidably rotate. Built-in washer 41 and washer member 45 coact with a relatively small friction coefficient. Washer member 45 includes perpendicularly and peripherally mounted tongue 45 ′ that is positioned inside channel 24 . Sprocket member 42 includes central through opening 43 with internal sawtooth formation 44 formed adjacent to internal wall 47 and extending approximately to half the height of sprocket member 42 . Pin member 48 includes headed end 49 , which includes circular surface 49 ′. The underside of headed end 49 includes sawtooth skirt 51 that extends perpendicularly from surface 49 ′. End 48 ′ of pin member 48 is rigidly mounted to louver clip member 46 . Clip member 46 has legs 38 and 38 ′ extending parallel to each other. Leg 38 includes internal hook member 46 ′. End 48 ′ has cooperative dimensions to be received within opening 43 and internal sawtooth formation 44 mesh with internal sawtooth skirt 51 so that rotating sprocket member 42 transmits the movement to sawtooth skirt 51 .
Chain 60 is of the ball chain type, preferably. Chain 60 is housed within channel 24 on the outer surface of arched back member 22 ′, as best seen in FIG. 2 . Chain 60 is preferably actuated by a user through actuating lever 62 and cable 61 , as seen in FIGS. 1 and 3. Chain 60 slides inside channel 24 and meshes with sprocket 42 at a point where channel 24 passes tangentially next to recessed through opening 23 . Tongue 45 ′ provides a hard surface to links 66 causing it to press against sprocket member 42 . Moving chain 60 causes sprocket 42 to rotate and thus louver members 30 rotate.
Recessed through openings 23 includes counterbore shoulder 25 . In the preferred embodiment, washer member 45 rests on counterbore shoulder 25 avoiding the frictional forces of sprocket assembly 40 ′ and chain 60 against counterbore shoulder 25 . Ball links 66 of chain 60 cooperatively coact with sprocket member 42 to convert the translational movement into rotational movement. Sprocket assembly 40 ′ transmits the rotational movement to pin member 48 and clip 46 causing blind or louver member 30 to rotate.
By maintaining blinds or louver members 30 taut at ends 34 , ends 32 are moved in tandem with chain 60 . Different types of chain can be used provided that they co-act with sprocket 42 . Mechanism 40 is actuated by a user, preferably through the use of actuating lever 62 located at the center of lower frame member 26 , as seen in FIG. 1 . Control lever 62 is connected to chain 60 through hook member 64 and cable 61 . The system is volumetrically efficient and thus capable of being mounted with minimum space requirements.
Another embodiment for the present invention 100 is represented in FIGS. 6; 7 ; 8 ; 9 ; 11 and 12 , for a louvered arch mechanism. This embodiment can be used for perfect of imperfect arches. By imperfect or non-perfect arch is meant an arch with a center that falls beyond the straight frame member. Louvered arch mechanism 100 includes arched frame assembly 120 , blinds or louver members 130 , actuating mechanism assembly 140 and tensioning assembly 150 . Imperfect blind assemblies 120 are aesthetically desired when there is no sufficient ceiling height or it is merely desired by a user. The problem with these designs is that louver holding pin member 148 is kept at an angle with respect to arched back frame member 122 ′.
Arched frame assembly 120 includes arched frame member 122 and straight frame member 126 . Member 122 extends from one end of member 126 and joins the other end of member 126 . Arched anchorage member 128 is centrally mounted on member 126 extending at a parallel and spaced apart relationship with respect to arched frame member 122 . Arched frame member 122 includes arched back frame member 122 ′, arched cover frame member 122 ″, channel 124 on the outer surface of arched back frame member 122 ′, and recessed through openings 123 through which louver holding pin member 148 passes, as shown in FIG. 9 . Clip member 146 is mounted to end 132 of louver member 130 . Pin member 148 is rigidly mounted to clip member 146 and the former has cooperative dimensions to pass recessed through opening 123 to engage with sprocket member 142 .
Actuating mechanism assembly 140 , includes sprocket assembly 140 ′, louver holding pin member 148 , chain 160 , cable 161 , hook members 164 and actuating lever 162 , as seen in FIGS. 6 and 7. Sprocket assembly 140 ′ can be used for the embodiment represented in FIGS. 6; 7 ; 8 ; 9 ; 11 and 12 , involving non-perfect (or imperfect) arch frames (where the radius of curvature is different at different points of the arch). The difficulty with these arch frames is that, for most blinds or louver members 130 , counterbore shoulder 125 is not in a perpendicular disposition with respect to the longitudinal axle of pin member 148 , as best seen in FIGS. 11 and 12. Blinds or louver members 130 include distal end 132 and proximal end 134 . Sprocket assembly 140 ′ has upper and lower ends and includes sprocket member 142 with built-in washer 144 rigidly mounted to the lower end of sprocket assembly 140 ′, headed end 149 rigidly mounted to louver holding pin member 148 and clip member 146 . Headed end 149 has a substantially hemispherical shape with flat upper end 149 ′. Headed end 149 includes radial pin members 141 cooperatively disposed around headed end 149 next to upper end 149 ′. Sprocket member 142 includes through opening 143 with socket 147 and internal radially-grooves 143 ′ cooperatively disposed to receive pin members 141 therein. Socket 147 has cooperative dimensions to receive headed end 149 .
As shown in FIG. 9, actuating mechanism assembly 140 and louver members 130 move between two extreme positions as shown in phantom with 130 ′ and 130 ″. Extreme positions 141 ′ and 141 ″, respectively, for pin members 141 that move along internal grooves 143 ′.
Blinds or louver members 130 have different dimensions being the longest ones the ones on the sides and the shorter ones the ones in the center, as seen in FIGS. 6 and 11.
Chain 160 is housed within channel 124 tangent to opening 123 . Built-in washer 144 rests on washer member 145 . Washer member 145 rests in counterbore shoulder 125 avoiding the frictional forces of sprocket assembly 140 ′ and chain 160 against counterbore shoulder 125 . Ball links 166 of chain 160 coacts with sprocket member 142 causing the latter to rotate. Sprocket member 142 transmits the rotational movement to pin member 148 and clip member 146 causing louver members 130 to rotate.
Washer member 145 , like washer member 45 , includes perpendicularly mounted tongue 145 ′, arms 345 and 345 ′ and central through opening 445 , as seen in FIG. 10 . Washer member 145 rests on counterbore shoulder 125 and arms 345 and 345 ′ are positioned inside channel 124 adjacent to recessed through opening 123 . Arms 345 and 345 ′ prevent the rotation of washer member 145 with the movement of actuating mechanism assembly 140 and chain 160 . Tongue 245 is positioned adjacent to the farthest wall of channel 124 providing a hard surface against which ball links 166 coact with sprocket assembly 140 ′, as best seen in FIGS. 7 and 9 (and FIGS. 3 and 4 for washer member 45 ).
The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense. | A louver assembly for semi-circular, non-perfect or imperfect arch frame assemblies with louvers rotably mounted therein. A tensioning mechanism keeps the louvers taut between an arched frame member and a smaller anchorage frame member. An actuating mechanism is used to rotate the louvers upon the application of a predetermined force to a chain that coacts with teethed sprockets coupled with hooked clip members that removably hold the louvers. In this manner, the louvers are rotated between two extreme positions. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention pertains to the art of laundry appliances, and more particularly, to a menu driven electronic interface system used in controlling the operation of a laundry appliance.
[0003] 2. Discussion of the Prior Art
[0004] Automatic commercial washing machines have traditionally been operated from stored programs or manually actuated buttons. There is known in the art of washing machines a large number of electronic control systems for washing machines which arrive from the factory with a variety of settings. These settings often include wash temperatures and time settings for the various operations performed by the washing machine. Commonly present in modem washing machines are settings which optimally clean different fabrics. Depending upon the type of fabric chosen, the settings direct the various operations of the washing machine. It is also known in the art to provide on-premise laundry systems with pre-programmed operational cycles. Frequently, these pre-programmed operational cycles are organized into a slate which gives a user a number of different cycles from which to choose.
[0005] Because the cycles are pre-programmed at the factory, each machine is particularly designed for a specific environment. Typically, a machine is pre-programmed with cycles relating to types of fabric usually found in that environment. For example, a machine may be programmed with a slate directed to the fabrics found in a home, hotel, hospital, restaurant, or health club. Because the types of soiled fabrics differ in each environment, the slate is specifically tailored to the types of fabric used, as well as typical stains found on the fabrics, in that environment. For example, if a machine is to be used in a hospital, the cycles from which the user may choose are pre-programmed to optimally clean the fabrics typically found in a hospital setting. If the machine was to be used in a health club, the cycles would differ because the typical fabrics and stains encountered in a health club vary from that of a hospital. Therefore, depending upon the expected location and environment of the machine, the various cycles available are preset at the factory or by the installer.
[0006] In a domestic washing machine, the cycles are often designed to clean the fabrics and stains usually encountered in the home. Most commonly, one cycle is provided for whites, another for colors, and a third for delicates. In any event, the manufacturer provides the machine with the various cycles pre-programmed. In general, the various cycles can be accessed by a consumer of the washing machine through a series of buttons and/or a rotating dial. When a specific cycle is desired, a user only needs to press an appropriate button, perhaps in combination with setting the dial, on the face of the washing machine to begin the operation. This design, while simple to manufacture and operate, limits the versatility of the overall system to most effectively clean a wide range of fabrics.
[0007] U.S. Pat. No. 5,585,704 to Elzind teaches incorporating a microprocessor based control system into a washing machine in order to allow the changing of pre-programmed cycles after installation. The system proposes to replace the pre-existing manual operation push buttons with a module connected to an automatic controller. The controller includes a control circuit which uses a series of manual push buttons. Through the manual push buttons, the user is able to select between various wash programs. The controller also includes a removable and replaceable solid-state memory card which stores multiple wash programs. These memory cards, once inserted into a memory card driver present on the machine, provide multiple wash programs to the machine, allowing the archiving and up-loading of various wash programs. Although the system allows the alteration of various wash cycles programmed in a washing machine, the selection of wash cycles is limited to those present on the memory cards. Additionally, such a system requires external peripherals to add more settings. Therefore, users are limited to the current slate programmed into the machine. In addition, although it may be possible to load other cycles into the machine, it is difficult to change each of the cycles for optimal use in another environment. Additionally, a new slate of cycles cannot easily be loaded into the machine. Furthermore, with conventional washing machines, changing the individual parameters, other than a single wash cycle, is difficult at best.
[0008] Therefore, there exists a need in the art for a domestic washing machine which is manufactured with a variety of washing operations and is capable of taking on supplementary cycle operations at the direction of the user. There also exists a need for a more user friendly system for controlling the operation of a washing appliance, rather than a conventional mechanical button operation. More specifically, there exists a need for an electronic control system which functions to prompt a user, as needed, to input certain washing information in a convenient and concise manner, and then automatically controls the washing appliance to perform the desired operation. Furthermore, there is a need for an electronic washing appliance control system which can itself be programmed to perform various operations in a desired manner, such as following a personal washing schedule stored in the system by the user. Corresponding needs exist in other known laundry appliances as well.
SUMMARY OF THE INVENTION
[0009] The present invention pertains to a system for programming and operating a laundry appliance, based on selections made by a user. In the most preferred embodiment wherein the invention is employed in a washing appliance, a menu driven display, such as a touch screen, is used to prompt a user for programming inputs, as simple as the type of fabric to be cleaned to the degree or level of soiling, or as complex as the desired water extraction speed and temperature. In addition to prompting the user for necessary programming information, the washing appliance can pause the programming sequence to automatically perform rinse, extract, or dispensing sequences as needed, preferably while displaying a control screen to the user concerning the function being performed.
[0010] Additionally, the user is provided with a plurality of menu screens with which to operate and control the washing machine of the invention. Specifically, the washing machine includes a touch screen which allows the user to start the operation of the machine simply by pressing the correct area of the touch screen. The touch screen also gives the user access to a variety of databases, including washing instructions and tips, as well as help information for operating and programming the washing machine.
[0011] Additional objects, features and advantages of the present invention will become more readily apparent from the following detailed description of preferred embodiments thereof when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a perspective view of a domestic washing machine incorporating the menu driven control system of the invention;
[0013] [0013]FIG. 2 is a detailed view of the display, including an initial operating screen as presented to a user;
[0014] [0014]FIG. 3A is a diagrammatic representation of the first operating screen;
[0015] [0015]FIG. 3B is a diagrammatic representation of operating screens seen by the user during general operation;
[0016] [0016]FIG. 4 is a diagrammatic representation of operating screens encountered by the user during a help sequence;
[0017] [0017]FIG. 5 is a diagrammatic representation of operating screens seen by the user during a service sequence;
[0018] [0018]FIG. 6 is a diagrammatic representation of operating screens seen by the user during a diagnostic sequence;
[0019] [0019]FIG. 7 is a diagrammatic representation of operating screens seen by the user during a cycle programming sequence;
[0020] [0020]FIG. 8A is a diagrammatic representation of a second embodiment of an initial operating screen set as presented to the user;
[0021] [0021]FIG. 8B is a diagrammatic representation of operating screens seen by the user during a general sequence; and
[0022] [0022]FIG. 8C is a diagrammatic representation of operating screens seen by the user during a cycle programming sequence.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] With initial reference to FIG. 1, an appliance 1 is schematically shown in the form of a washing machine. Appliance 1 includes a cabinet 2 provided with a door 3 in a front face 4 . Door 3 is designed to be pivoted to expose an integral washing tub (not shown). A display 10 is provided through which a user controls and programs washing appliance 1 . As will become more fully evident below, the particular construction of washing appliance 1 can significantly vary in accordance with the present invention. Display 10 includes a plurality of selectable control areas or zones 15 (see FIG. 2), which can be accessed by a user to both program and operate washing machine 1 .
[0024] In the most preferred form of the invention, display 10 takes the form of an LCD display, such as a 128×96 dot matrix, touch screen display, which enables a user to readily review displayed data, preferably in alpha or word text format, and select from that data to establish and begin a desired washing operation. Display 10 , although shown with the various selectable areas 15 near or close to the comer and side portions of display 10 , could have the selectable areas 15 at any location on the display. The manner in which washing appliance 1 operates in accordance with the most preferred embodiment will be described in detail below, particularly with reference to the diagrams of FIGS. 3 - 7 . However, at this point it, should be realized that, in addition to the control options presented in these figures, appliance 1 may also include various buttons, such as “POWER”, used to selectively turn on or off washing appliance 1 , and “BACK/CLEAR”, used to erase an inadvertently inputted control parameter through display 10 . Additionally, display 10 may include a FAVORITES button which gives the user quick access to the most often used cycles and functions.
[0025] Reference will now be made to FIG. 3 in describing various, preferred programming sequences in accordance with the invention. Upon activating washing machine 1 , a user is presented with screen 100 . As shown, screen 100 preferably presents various operating options for washing appliance 1 . With screen 100 displayed, the user can select a desired operating command, preferably by simply touching a portion of display 10 in which a key word is indicated. As shown, the user can select “Hints & Tips”, “Select Cycle”, “Help”, or “Quit” options. Further details of the operation of washing appliance 1 upon selecting each of the options will be presented more fully below.
[0026] [0026]FIG. 3A particularly illustrates a preferred sequence when the user programs washing appliance 1 under the “Hints & Tips” option. Specifically, the “Hints & Tips” option is used to access washing assistance databases preferably stored in memory of washing appliance 1 , and changes display 10 to a different screen configuration, screen 110 . Alternatively, the databases may be stored in external accessible memory. As shown in FIG. 3 a , the user can select from “Laundry Advice” or “Stain Removal”, as well as “Return to Main Menu”.
[0027] Selecting the “Laundry Advice” option from screen 110 accesses screen 120 , as shown in FIG. 3B. The “Laundry Advice” option causes washing appliance 1 to access a stored database containing a variety of suggestions for washing, and to display one of the suggestions contained therein. Because washing appliance 1 preferably, randomly displays a suggestion from the database, repeatedly selecting the “Laundry Advice” option will successively display additional suggestions.
[0028] Also shown in FIG. 3B is screen 130 which is entered by selecting the “Stain Removal” option from screen 110 . Screen 130 presents the user with common types of stains, or an alphabet listing used to input spelling information on a common stain, and, by selecting the specific stain type, suggestions for best cleaning of that type of stain. As shown, screen 130 includes exemplary options for “Oil & Grease” and “Protein”. Screen 140 results from selecting the “Oil & Grease” option. Although screen 130 is shown as including only two specific stain types, screen 130 may include a variety of additional stain types, such as “Grass”. Additionally, screen 130 may present the user with an algorithm with which to determine the type of stain. Furthermore, although screen 140 is shown as presenting particular advice on cleaning an oil and grease stain, it must be remembered that screen 140 is only exemplary and that washing appliance 1 can change screen 140 , depending upon the desired instructions and type of stain chosen in screen 130 .
[0029] Washing appliance 1 is provided with a help sequence, shown in detail in FIG. 4, which is activated by selecting the “Help” option from screen 100 . The help sequence is initially displayed to the user in screen 150 . Selecting a “How to . . . ” option from screen 150 causes washing appliance 1 to display screen 160 , which presents the user with a variety of general washing procedures and suggestions for each. It is also within the scope of this invention to provide a plurality of additional screens which can be accessed by selecting one of the washing procedures for additional help and suggestions.
[0030] Screen 150 also provides the user with a “Before Calling for Service . . . ” option which presents a series of commands to the user to perform before calling a service technician, and causes display 10 to show screen 170 . These commands are designed to alleviate the necessity of calling the service technician prior to considering basic potential problem areas, such as checking the various supply and waste hoses. The specific text displayed in screen 170 is only to be considered exemplary, and may alternatively show other suggestions, as well as provide additional screens which assist the user with an algorithm to determine the problem.
[0031] A “Service Menu” option is also provided from screen 150 as shown in detail in FIG. 5. Selecting this option changes display 10 to screen 200 and gives the user a variety of additional options for servicing washing appliance 1 . A “Demonstration Mode” option is available, through which the tumble action, or other washing operations, are exhibited (screen 210 ). Additionally, a “Help Mode” option is provided, wherein “Help Codes”, “Extended Fill Option”, “Software Revision”, “Spinner RPM”, as well as other types of service help information are displayed (screen 220 ).
[0032] Selecting a “Machine Status” option shows the current condition of washing appliance 1 . Screen 230 shows the number of cycle counts as one potential condition which may be displayed.
[0033] Selecting a “Set Up” option from the service menu screen 200 gives the user the ability to set up the washing operation of washing appliance 1 . Specifically, screen 240 (see FIG. 4) presents the user with a “Cycle Set Up” option, a “Counter Set Up” option, and a “Language Set Up” option” as a sample of the type of options given in the setup mode. The “Cycle Set Up” option is used to redefine one or more steps of an individual cycle, such as demonstrated in co-assigned U.S. patent application entitled, “Programmable Laundry Appliance”, filed on even date herewith, and incorporated herein by reference. The “Counter Set Up” option is used to display and reset a running counter which calculates the number of times each cycle has been actuated and, optionally, the number of times each of the menu systems has been accessed, as well as error code counts. The “Language Set Up” option can be used to change the language which is displayed by washing appliance 1 . That is, because washing appliance 1 has access to an internal or an external database, it is possible to have a non-English language displayed.
[0034] [0034]FIG. 6 diagrams the screens of a diagnostics mode of the washing appliance 1 , which is accessed via a “Diagnostics” option from screen 200 . An initial screen 250 of the diagnostics mode presents the user with a “Field Test Cycle” option which runs washing appliance 1 through a specially designed diagnostic cycle to test the operation of washing appliance 1 . Screen 260 shows a preferred screen displayed during the “Field Test Cycle” option to convey the current status and progression of the test cycle. A similar “Factory Test Cycle” option is provided, which runs washing appliance 1 through a different specially designed diagnostic cycle to test the operation of washing appliance 1 . Screen 270 shows a preferred screen displayed during the “Factory Test Cycle” option to indicate the current status and progression of the test cycle. Screen 280 shows codes, explanations and troubleshooting guides resulting from the selection of the “Diganostics Codes” option from screen 250 .
[0035] Choosing a “Select Cycle” option from screen 100 presents the user with a set of cycles and operations from which to choose, as best shown in FIG. 7. First, the user chooses the type of fabric to be cleaned in screen 300 . Next, via screen 310 , the user chooses the type of cycles to be followed. Specifically, screen 310 shows a “Normal Cycle”, a “Wash/Rinse”, and a “No Delay” cycle, but optionally may contain various types of automatic cycle used in domestic or commercial washing machines. The parameters, such as wash temperature, spin speed, and additive used, are determined by the selection of fabric type and wash type. Sample types of cycles are demonstrated in the above-identified co-pending application entitled, “Programmable Laundry Appliance”.
[0036] Selecting “More Options . . . ” presents the user with screen 320 . Screen 320 essentially includes a plurality of washing options 324 and associated check-boxes 326 . For example, screen 320 is shown with options for “Max Extract”, “Stain Cycle”, “Extra Rinse” and “Signal”, which each relate to different aspects of the washing cycle. When a specific washing option is selected, the user only needs to touch the desired washing option 324 or its check-box 326 . Once selected, check-box 326 is filled on display 10 , with a check symbol or by otherwise filling in check-box 326 . Because only the contents of check-box 326 changes when washing option 324 is selected, the user is given the ability to choose one or more washing options 324 without substantial change in display 10 , until “Start Cycle” is selected.
[0037] At this point, it should be realized that the options presented in screen 320 are only a sample of the potential options which may be presented to the user. The “Max Extract” option, when selected, causes washing appliance 1 to spin a washing tub (not shown) at an elevated RPM and for an extended time during the final extract step of the washing cycle. The “Stain Cycle” is a specially designed additional set of steps added to the cycle which increases the stain removal capabilities of washing appliance 1 . Washing appliance 1 may additionally include a series of screens through which the user can define the type of stain to better assist washing appliance 1 in removing the stain. The “Signal” option, when selected, turns on an audible signal to alert the user of the completion of a selected cycle. It is also contemplated that the signal can be delivered via other means, i.e. telephone call, facsimile, or electronic mail, if washing appliance 1 is so equipped. However, it must be remembered that these options are only a representative sample of the types of options which are available through screen 320 . It is also contemplated that screen 320 can be replaced with a plurality of screens, or even a scrolling screen, giving more space for presentation and selection of the available options. Screen 320 , as well as screen 310 , also preferably includes a “Start Cycle” option through which washing appliance 1 begins the washing cycle. Screen 330 is then shown to display information such as fabric type, time remaining and door lock status as the cycle progresses.
[0038] [0038]FIGS. 8A, 8B and 8 C demonstrate a menu control system in accordance with a second embodiment of the invention. Preferably, the menu control system of this embodiment is somewhat simpler than the system of the first embodiment. Initially, as shown in FIG. 8A, the user is presented with screen 500 . Screen 500 has been designed with custom information, such as a family name, but may alternatively include any customized alphanumeric information. Touching any specified area of screen 500 moves to screen 510 , which is similar to screen 100 of the first embodiment. As shown, screen 510 preferably presents various operating options for washing appliance 1 . With screen 510 displayed, the user can select a desired operating command, preferably by simply touching a portion of display 10 in which a key word is indicated. As shown, the user can select “Hints & Tips”, “Select Cycle”, “Help”, or “Quit” options.
[0039] The “Select Cycle” option changes display 10 to screen 520 . First, the user chooses the type of fabric to be cleaned. Next, via screen 530 , the user chooses the type of cycle to be used. Specifically, screen 530 shows a “Normal Cycle”, a “Wash/Rinse”, and a “No Delay” cycle, but optionally may contain any type of automatic cycle used in a domestic or commercial washing machine. The parameters, such as wash temperature, spin speed, and additive used, are determined by the selection of fabric type and wash type. Sample types of cycles are also demonstrated in the co-pending application entitled, “Programmable Laundry Appliance”, as referenced above.
[0040] Selecting “More Options . . . ” presents the user with screen 540 . Screen 540 essentially includes a plurality of washing options 542 and associated check-boxes 546 . For example, screen 540 is shown with options for “Max Extract”, “Stain Cycle”, “Extra Rinse” and “Signal”, each of which relates to different aspects of the washing cycle. When a specific washing option is selected, the user only needs to touch the desired washing option 542 or its associated check-box 546 . Once selected, check-box 546 is filled on display 10 , with a check symbol or by otherwise filling in check-box 546 . Because only the contents of check-box 546 changes when washing option 542 is selected, the user is given the ability to choose one or more washing options 542 without substantial change in display 10 in a manner similar to screen 320 . Screen 540 , as well as screen 530 , includes a “Start Cycle” option to cause washing appliance 1 to begin the washing cycle. Screen 550 is then shown, and displays information such as fabric type, time remaining and door lock status.
[0041] From screen 530 , the “Wash/Rinse” option activates screen 570 . Screen 570 gives the user the ability to choose the temperature of each of the wash step and the rinse step. Simply selecting a combination, either “COLD/COLD”, “WARM/COLD”, “WARM/WARM” or “HOT/COLD” returns display 10 to screen 530 .
[0042] Also from screen 530 , the “No Delay” option activates screen 580 . Screen 580 gives the user the ability to choose each of the options and cycles to be used, but delay the start of washing appliance 1 . Options for “No Delay”, “2 Hour Delay”, “4 Hour Delay” and “8 Hour Delay” are shown, but a wide range of delay times may be provided. Simply selecting a delay time returns display 10 to screen 530 .
[0043] The operation of the “Hints & Tips” and “Help” options are identical as the operation in the first embodiment, such that these features will not be discussed further here. Based on the above, it should be apparent that the menu driven control system of the invention provides an enhanced system for programming, as well as increasing the versatility, of a washing machine. However, although described with reference to preferred embodiments, it should be readily understood that various changes and/or modifications could be made to the invention without departing from the spirit thereof. For instance, although the figures depict specific progressions of screens, it is within the scope of this invention to shuffle and reorganize the screens, with one or more of the screens and options being replaced or even eliminated. In addition, the invention can also be applied to other laundry appliances such as a dryer. In any event, the invention is only intended to be limited by the scope of the following claims. | A system for operating and programming a laundry appliance includes a menu system giving a user extreme flexibility in operating the appliance. Through a series of menu screens, the user is presented with a variety of available options. Additionally, the laundry appliance of the invention gives the user access to databases, preferably already programmed into memory of the appliance, such as general tips for laundering and simple troubleshooting. Finally, the user has the ability to program the menu system. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from provisional application No. 60/262,020 filed on Jan. 16, 2001.
BACKGROUND OF INVENTION
[0002] Focal plane mass spectrometers are known. For example, one popular focal plane type mass spectrometer is of the so-called Mattauch-Herzog geometry. These devices spatially separate ions having different masses along the focal plane. An advantage of this kind of spectrometer operation is that 100 percent duty cycle is possible along with the high sensitivity for ion detection. This compares with previous systems such as photographic plates, which may be cumbersome and may lack sensitivity.
[0003] An electro-optic ion detector (EOID) is described in U.S. Pat. No. 5,801,380 for the simultaneous measurement of ions spatially separated along the focal plane of the mass spectrometer. This device may operate by converting ions to electrons and then to photons. The photons form images of the ion-induced signals. The ions generate electrons by impinging on a microchannel electron multiplier array. The electrons are accelerated to a phosphor-coated fiber-optic plate that generates photon images. These images are detected using a photodetector array.
[0004] The EOID, although highly advantageous in many ways, is relatively complicated since it requires multiple conversions. In addition, there may be complications from the necessary use of phosphors, in that they may limit the dynamic range of the detector. A microchannel device may also be complicated, since it may require high-voltage, for example 1 Kv, to be applied. This may also require certain of the structures such as a microchannel device, to be placed in a vacuum environment such as 106 Torr. At these higher pressures of operation, the microchannel device may experience ion feedback and electric discharge. Fringe magnetic fields may affect the electron trajectory. Isotropic phosphorescence emission may also affect the resolution. The resolution of the mass analyzer may be therefore compromised due to these and other effects.
SUMMARY OF INVENTION
[0005] The present application defines a charge sensing system which may be used, for example, in a Mass Spectrometer system, e.g. a GCMS system, with a modified system which allows direct measurement of ions in a mass spectrometer device, without conversion to electrons and photons (e.g., EOID) prior to measurement. An embodiment may use charge coupled device, “CCD” technology. This CCD technology may include metal oxide semiconductors. The system may use direct detection and collection of the charged particles using the detector. The detected charged particles form the equivalent of an image charge that directly accumulates in a shift register associated with a part of the CCD. This signal charge can be clocked through the CCD in a conventional way, to a single output amplifier. Since the CCD uses only one charge-to-voltage conversion amplifier for the entire detector, signal gains and offset variation of individual elements in the detector array may be minimized. This may prove to be an advantage over CMOS technology.
DETAILED DESCRIPTION
[0006] [0006]FIG. 1 shows an embodiment. A mass spectrometer system 98 , which may be a gas chromatograph-mass spectrometer combination or a mass spectrometer alone, produces ions along a focal plane 99 . Ions of different masses are spatially separated along the focal plane. These ions should be measured along the focal plane with individual detectors with high spatial resolution. According to the embodiment, measurement of the ions on the focal plane may use an electronic linear array detector.
[0007] An array of capacitive elements coupled to a CCD shift register form a detector for the charged particles along the focal plane. In the embodiment, a linear array of CCD pixels 100 , 105 , 110 , 115 is formed along a focal plane 99 . Each pixel is formed using conventional three-phase CCD process technology. Each pixel has a capacitive sensing element part 130 , formed of two layers of conductive material insulated from one another. The conductive material may be, for example, aluminum or other conductive wiring material. The capacitive sensing elements may be coupled to the CCD shift register using a charge mode input structure 135 . The charge mode input structure is typically known as a fill-and-spill input structure. This element senses the charge that is collected on a capacitive sensing element and creates a packet of signal charge that is proportional to the charge on the capacitor. Fill and spill is well known in the art, and is described, for example, in D. D. Buss et al, “Applications to Signal Processing”, Charge Coupled Devices And Systems, 1979. Fill and spill may produce linearity of greater than 100 db with negligible offset levels. The fill and spill structure may also effectively provide gain in the charge domain. For example, the charge mode amplifier in this embodiment may have a gain of 10. The output of the charge mode amplifier is sent to a signal collection area 140 , and then to a CCD shift register 145 . Further detail on this structure is provided herein.
[0008] [0008]FIG. 2 shows a representation of the unit cell operating as a charged particle detector. As described above, the ions are captured by a pair of electrodes, including an ion capture electrode 200 ,and a bottom electrode 202 . Incident charged particles are captured by the electrode pair.
[0009] Each of the electrodes is connected to a respective transistor; electrode 200 is connected to transistor 205 and electrode 202 is connected to transistor 206 . The transistors are actuated to periodically reset the potential on the electrodes 200 , 202 to a reset level. Gates 210 are located below the electrodes. The gates 210 comprise the fill and spill input, level control gates and CCD register part. A controller 250 , which may be part of the detector, or some external unit, may control the production of the signals described herein, in the sequence that is described herein.
[0010] [0010]FIG. 3 illustrates the device initialization procedure, in which the detection capacitor 199 is initialized and reset. The first part of the device operation requires that the top and bottom electrodes 200 , 202 of the detection capacitor 199 be reset to a known potential. The respective field effect transistors 205 are therefore actuated to apply a known potential to the electrodes 200 , 202 . The bias on DD 1 may be lowered. A bias is also applied via the “SIG” gate.
[0011] [0011]FIG. 4 illustrates releasing the capacitors from reset, and filling the “reservoir” area, under the reservoir gate 400 , with charge, as part of the fill and spill. First, the bias applied to the diode region DD 1 is raised towards ground. This has the effect of providing a source of charge which spills over the barrier formed by the gate DC and into the reservoir area. During this time, the gate DDG is held in the on state, which allows overflowing charge to be directly removed from the structure through the drain diode DDO.
[0012] In FIG. 5, the reset FETs 205 , 206 are turned off. The diode DD 1 is also rebiased to its initial positive level. The output gate DDG/TG is maintained off. This allows the signal in the reservoir to come to equilibrium. In this way, any residual reset charge is removed.
[0013] This fill and spill operation as described above may substantially compensate against sensitivity to the absolute voltage level that is applied to the capacitor plates. Thus, any variations in FET threshold, both inherent FET threshold, and radiation induced FET threshold, become less important. These variations may not result in signal offset variations within the unit cells that form the detector array. This may also remove KTC noise that may otherwise be present as a result of filling a well with charge via a diode source.
[0014] [0014]FIG. 6 shows the result when all equilibrium operations are complete. The structure then begins to detect charged particles. As the particles are detected on the capacitor plates, the charge from those particles changes the voltage level on the gate SIG. This voltage change allows packets of charge to flow from the reservoir, across the SIG gate and into the collection wells under the gates W- 2 and W- 3 . By using a large reservoir and a smaller SIG gate, amplification may occur in the charge domain. A small change on the SIG gate may produce a larger amount of charge flow from the reservoir. At the end of a desired part of the cycle, the DDG/TG gate may be biased to prevent further charge transfer.
[0015] [0015]FIG. 7 illustrates the end of the integration cycle. The potential level within the silicon well defined by the SIG gate potential determines the amount of integrated signal charge. The charge detection and signal integration can continue until the potential produced by the SIG gate drops below the level of charge that is being held under the reservoir. In reality, integration can be halted at any time using the reset transistors 205 , 206 .
[0016] [0016]FIGS. 8 and 9 show how the collected signal charge is transferred from the storage wells under gates W- 2 , W- 3 into the CCD shift register S 1 , S 2 . FIG. 8 shows transferring the charge form the collection region into the CCD shift register. Then, FIG. 9 shows the completed operation, with the charge in the CCD shift register. The transfer is carried out by applying appropriate biases to the control gates. Charge is then detected at the output of the CCD shift register by a standard charge-to-voltage conversion stage.
[0017] Although only a few embodiments have been disclosed in detail above, other modifications are possible. For example, the embodiment disclosed above describes using a single, large, detection capacitor formed from two continuous plates. An alternative system, however, may use a series of smaller detection capacitors, connected in series through a second set of CCD registers. The second set of registers may be connected orthogonal to the CCD shift register. The registers may sum charge packets from each of the small capacitances. This system may allow faster operation and improved noise performance in some conditions.
[0018] All such modifications are intended to be encompassed within the following claims, in which: | An electronic ion detection system which may detect low-energy charge particles such as ions from, for example, a mass spectrometer system. The capacitive sensors are located with two plates which are separated by an insulator. The ions which impinge on one of the plates cause charge to be created. That charge may be amplified and then handled by a charge mode amplifier such as a CCD sensor. That CCD sensor may operate using fill and spill operations. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. Non-Provisional Application No. 12/ 724,563 filed Mar. 16, 2010, now abandoned, which is a continuation of U.S. Non-Provisional Application No. 12/274,814 filed Nov. 20, 2008, now abandoned, which claims the benefit of prior U.S. Provisional Application No. 61/003,748, filed Nov. 20, 2007.
FIELD OF THE INVENTION
The present invention relates generally to self-standing riser systems used during energy exploration and production, and in a particular though non-limiting embodiment, to a system useful for deploying self-standing risers and associated buoyancy devices in a variety of operating conditions.
BACKGROUND OF THE INVENTION
Over the past decade, there has been an increasing worldwide demand for oil and gas production. At present, however, oil and gas supply continues to lag far behind demand, a situation which has at times contributed significantly to worldwide economic difficulties and could well present a major concern for many years to come.
In an effort to balance supply and demand, companies and governmental entities have begun to explore and develop relatively marginal fields in the deeper offshore waters of the Gulf of Mexico, West Africa and Brazil. However, due to high construction costs and limited manufacturing facilities, only a small number of mobile offshore drilling units (MODUs) are being manufactured each year, thereby resulting in escalating “per day” unit costs and a shortage of associated offshore drilling, completion and workover equipment.
Moreover, even though the cost differential between drilling operations and completion or workover operations is relatively modest (since MODUs usually perform all of these functions during a typical operation), most such projects are still inefficient, because a MODU actively performing one function (e.g., drilling) is generally not able to accomplish any other functions (e.g., completion or workover).
In other applications by this inventor, it has been shown that a self-standing riser system can be safely and reliably installed in communication with a well head or production tree. Such risers by design are self-supporting, and provide all of the necessary risers, casing, buoyancy chambers, etc., required for exploration and production and of oil, gas and other hydrocarbons. Self-standing risers also provide the requisite safety features required to ensure that the produced hydrocarbons do not escape from the system out into surrounding waters. For example, self-standing riser systems fully support both surface-based and semi-submersible platform interfaces, blow-out preventers, production trees, and other common exploration and production installations.
Known self-standing riser systems require either a number of different surface vessels or a MODU for installation, due to the size and weight of riser stacks, drilling pipe, buoyancy devices, etc. For many installations, expensive hull and deck modifications also have to be made. Accordingly, few improvements in associated per-day costs have been realized.
There is, therefore, a need for a more cost-effective method of installing self-standing riser systems, which does not require the use of MODUs.
SUMMARY OF THE INVENTION
A water-borne vessel for deploying a self-standing riser system is provided, wherein the vessel hull is configured to receive, transfer and deploy components of a self-standing riser system. The vessel hull includes at least a landing platform, a component transfer means, and a deployment platform suitable for deploying the riser components into associated surrounding waters. Various means of assisting the process whereby self-standing riser components are loaded onto the vessel and stored; transferred from receiving to deployment platforms; and deployed from the vessel into surrounding waters are also considered.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a side view of a self-standing riser deployment vessel, according to example embodiments.
FIG. 1B is a schematic diagram depicting the submersion of a self-standing riser system, according to example embodiments.
FIG. 1C is a schematic diagram of a deployment vessel positioning a completed self-standing riser system, according to example embodiments.
FIG. 1D is a schematic diagram of a deployment vessel releasing from a completed self-standing riser system, according to example embodiments
FIG. 2A is a side view of a self-standing riser system deployment vessel, according to example embodiments.
FIG. 2B is top view of a self-standing riser system vessel equipped with a buoyancy device loading bay, according to example embodiments.
FIG. 2C is a schematic diagram depicting a buoyancy device being lowered into a buoyancy device loading bay, according to example embodiments.
FIG. 2D is a schematic diagram of a deployment vessel beginning its release of a deployed buoyancy device stack, according to example embodiments.
FIG. 2E is a schematic of a deployment vessel having released its load, and leaving the site prior to commencement of drilling operations.
DETAILED DESCRIPTION
The description that follows includes exemplary systems, methods, and techniques that embody various aspects of the presently inventive subject matter. However, it will be readily understood by those of skill in the pertinent arts that the described embodiments may be practiced without one or more of these specific details.
In other instances, well-known manufacturing equipment, protocols, structures and techniques have not been shown in detail in order to avoid obfuscation in the description.
Referring now to FIG. 1A , an example embodiment of a self-standing riser deployment vessel 6 is depicted, comprising a plurality of buoyancy devices 2 temporarily attached to the bottom of the hull. In exemplary embodiments, deployment vessel 6 is a workboat, anchor handling boat, or any other available vessel of suitable size and configuration; the lengths of such vessels might range, for example, from around 150 ft. to around 300 ft., though these size estimates should not be deemed as limitative.
Other embodiments of deployment vessel 6 comprise enough deck and storage space to carry associated riser tubing 4 , and additional buoyancy devices 2 . Still further embodiments employ dynamic positioning equipment (e.g., a spar), which facilitate efficient and reliable riser stack deployment and installation on the sea floor.
In one embodiment, an entire string of risers is assembled with one or more buoyancy devices interspersed as needed in order to provide sufficient buoyancy for the entire system. The string is then deployed as a continuous structure and lowered to the sea floor in a controlled manner. The top of the string is then secured and lifted so that it can be moved over the drilling site and attached to the well. In other embodiments, the system is deployed in a piecemeal fashion, with sections of a desired length being individually deployed and mechanically joined as the assembly is completed.
In the example embodiment illustrated in FIG. 1A , deployment vessel 6 further comprises a hoisting frame 3 disposed near a moon pool. The hoisting frame permits riser 4 stored within the vessel to be loaded and lowered or held in position. In various embodiments, the lowering, raising and holding of riser 4 is facilitated using conveyor belts, chains, rollers, etc. In one example embodiment, riser 4 is transferred from a storage container towards the moon pool using a conveyor belt, and subsequently connected to a fastening device affixed to hoisting frame 3 . The riser can then be deployed or held in a desired position in a safe and reliable manner.
Consistent with the example deployment vessel 6 illustrated in FIG. 1A , further embodiments also comprise loading mechanisms (e.g., frames, rails, etc.) used to load, guide and control the buoyancy devices 2 . FIG. 1A , for example, depicts two buoyancy devices 2 disposed in mechanical communication with the bottom of the hull of the deployment vessel 6 . The buoyancy devices 2 are affixed to a carrying frame 1 configured to reliably accommodate large, heavy loads. Carrying frame requirements will vary by project, but each such device should, at minimum, be capable of supporting the weight of one or more buoyancy devices. Electric, hydraulic or pneumatic lifts can be used to raise and lower the buoyancy devices, and ropes, chains, and tension lines reeled out from strategically placed winches can assist in the fine control necessary to ensure safe and controlled deployment of the buoyancy devices.
In some embodiments, each of said buoyancy devices 2 further comprises a connector 14 (i.e., a flange or receptive housing, etc.) that allows for attachment of additional buoyancy devices 2 or riser assemblies 4 .
In the example embodiment depicted in FIG. 1B , each of the buoyancy devices further admit to the passing of riser 4 through a void space in the buoyancy devices by means of a hoisting frame 3 , so that the riser 4 can subsequently be attached to a subsurface wellhead 8 installed atop a well bore 9 . A flanged member 18 can be used to help capture descending riser and assist in connection of the riser to the wellhead.
In the example embodiment illustrated in FIG. 1C , deployment vessel 6 is used to lower a fully assembled self-standing riser system into position for attachment with wellhead 8 . Guide frame 1 assists in the controlled deployment of the riser near the surface, and a flanged member 14 assists in capture of the lowered riser. In other embodiments, deployment vessel 6 utilizes dynamic positioning equipment (or alternatively, light equipment such as ropes, chains, winch lines, etc.) to lower, raise and support the riser stack as it is position above the wellhead. Further embodiments utilize buoyancy devices to tension the stack as deployment is carried out, and to dynamically position the riser between the vessel and the well.
As seen in FIG. 1D , once the self-standing riser system is deployed and attached to the well, the surface vessel releases its hold and the vessel can be used for other operations on a cost-effective basis. In some embodiments, the vessel deploys the self-standing riser and leaves the site so that other vessels (e.g., vessels with testing packages, separators, or even MODUs when one becomes available) can interface with the system and initiate completion, testing or workover operations.
Referring now to FIG. 2A , a side view of a deployment vessel is illustrated, comprising a plurality of buoyancy devices 2 and a reliable means for deployment thereof. Some embodiments comprise one or more of a loading crane, a hoisting frame, buoyancy device transmission and positioning means 5 , etc., disposed near a moon pool.
As seen in FIG. 2B , it may be convenient that the moon pool is formed at the aft end of the vessel. In an especially novel approach, the aft end is open, and the moon pool has only three sides 6 , so that greater flexibility in position is achieved. In still further embodiments, the buoyancy devices 2 are loaded onto the deployment vessel from a neighboring service vessel, whereafter operations are carried out as described above.
In the example embodiment depicted in FIG. 2A , a plurality of buoyancy devices 2 are loaded onto the deployment vessel from a neighboring vessel, positioned for deployment from the deployment vessel by a transmission means 5 , and then deployed into a body of water in a safe and controlled fashion that ensures efficient operations and maintenance of the buoyancy devices' structural integrity.
In some embodiments, a neighboring crane is used to lower the buoyancy devices onto a deployment vessel landing platform, as depicted in FIG. 2A . The landing platform can be either flooded (in the event the devices are intended for immediate deployment), or dry (in the deployment is intended for a later time, or if access is needed so as to permit outfitting or maintenance). If the landing platform is dry, intake ports are provided so that it can later be flooded, allowing easier transportation and deployment of the devices at or near the drilling site (see, for example, FIG. 2C ). Such embodiments would likely utilize winches, fastening mechanisms, etc., to secure and facilitate safe and reliable control of the devices. The deployment vessel can then transport and deploy the devices as described above.
In the example embodiment depicted in FIG. 2C , a barge or other transport vessel is used to transfer additional buoyancy devices to the landing platform of a deployment vessel by means of a rope, chain, winch line, etc. In one particular embodiment, the buoyancy devices are moved via roller tracks toward an overhead gantry, hoisted by a crane or other hoisting device, and lowered into the deployment pool.
In the example embodiment depicted in FIG. 2D , the buoyancy devices have been landed from a service vessel and lowered into the water. The devices are then towed in by a second deployment vessel and attached to its hull via winches, hooks, fastening mechanisms, etc., disposed in mechanical communication with the second deployment vessel. In FIG. 2E , the second deployment vessel has captured and secured the devices, and the service vessel has released its line. The service vessel can then repeat the process until the desired number of buoyancy devices has been transferred to a desired number of deployment vessels.
The foregoing specification is provided for illustrative purposes only, and is not intended to describe all possible aspects of the present invention. Moreover, while the invention has been shown and described in detail with respect to several exemplary embodiments, those of ordinary skill in the art will appreciate that minor changes to the description, and various other modifications, omissions and additions may also be made without departing from the spirit or scope thereof. | A water-borne vessel for deploying a self-standing riser system is provided, wherein the vessel hull is configured to receive, transfer and deploy components of a self-standing riser system. The vessel hull includes at least a landing platform, a component transfer means, and a deployment platform suitable for deploying the riser components into associated surrounding waters. Various means of assisting the process whereby self-standing riser components are loaded onto the vessel and stored; transferred from receiving to deployment platforms; and deployed from the vessel into surrounding waters are also considered. | 4 |
FIELD OF INVENTION
The present invention relates to filters for electromagnetic waves and more particularly, to RF filters which can be controlled electronically. Commercial YIG filters are available.
DESCRIPTION OF THE PRIOR ART
Ferroelectric materials have a number of attractive properties. Ferroelectrics can handle high peak power. The average power handling capacity is governed by the dielectric loss of the material. They have low switching time (such as 100 nS). Some ferroelectrics have low losses. The permittivity of ferroelectrics is generally large, as such the device Is small in size. The ferroelectrics are operated in the paraelectric phase, i.e. slightly above the Curie temperature to prevent hysteresis which introduces a hysteresis loss with an a.c. biasing field. Inherently, they have a broad bandwidth. They have no low frequency limitation as contrasted to ferrite devices. The high frequency operation Is governed by the relaxation frequency, such as 95 GHz for strontium titanate, of the ferroelectric material. The loss of the ferroelectric high Tc superconductor RF tunable filters is low for ferroelectric materials, particularly single crystals, with a low loss tangent. A number of ferroelectrics are not subject to burnout. Ferroelectric tunable filters are reciprocal. Because of the dielectric constant of these devices vary with a bias voltage, the impedance of these devices vary with a biasing electric field;
There are three deficiencies to the current technology: (1) The insertion loss is high as shown by Das, U.S. Pat. No. 5,451,567. (2) The properties of ferroelectrics are temperature dependent (3) The third deficiency is the variation of the VSWR over the operating range of the time delay device.
It is stated in U.S. Pat. No. 5,459,123, that Das used a composition of polycrystalline barium titanate, of stated Curie temperature being 20 degrees C and of polythene powder in a cavity and observed a shift in the resonant frequency of the cavity with an applied bias voltage based on the publication by S. Das, "Quality of a Ferroelectric Material," IEEE Trans. MTT-12, pp. 440-448, July 1964.
It is stated in U.S. Pat. No. 5,496,795 to Das, that Das discussed operation, of microwave ferroelectric devices, slightly above the Curie temperature, to avoid hysteresis and showed the permittivity of a ferroelectric material to be maximum at the Curie temperature and the permittivity to reduce in magnitude as one moves away from the Curie temperature based on the publication by S. Das, "Quality of a Ferroelectric Material", IEEE Trans. MTT-12, pp. 440-445, July, 1964.
It is stated in U.S. Pat. No. 5,496,795, that another object of this design is to design phase shifters to handle power levels of at least 0.5 Megawatt based on the publication by G. Shen, C. Wilker, P. Pang and W. L. Holstein, "High Tc Superconducting-sapphire Microwave resonator with Extremely High Q-values Up To 90K," IEEE MTT-S Digest, pp. 193-196, 1992.
SUMMARY OF THE INVENTION
The invention includes band pass and reject tunable filters in the configuration of four layer microstrip devices. A first layer is a sheet of a single crystal dielectric material. Examples of dielectric materials are sapphire and lanthanum aluminate. A second layer is a film of a single crystal high Tc superconductor deposited on the sheet of single crystal dielectric material and which is connected to an external ground. Examples of such superconductors are YBCO and TBCCO. A third layer is a film of a single crystal ferroelectric material deposited on the film of single crystal high Tc superconductor. Examples of single crystal ferroelectric materials are KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 where the value of x is between 0.005 and 0.7. A fourth layer contains microstrip lines, shaped for a band pass or a band reject filter, composed of a single crystal high Tc superconductor and deposited on the film of a single crystal ferroelectric material. Application of a bias voltage changes the permittivity of the ferroelectric material and the operating frequency of the tunable filter. Microstrip line quarter wavelength long transformers, deposited on the same ferroelectric material film as that used for the filter, are used to provide impedance matching of the input of the filter to an input circuit of the filter and matching the output of the filter to an output circuit of the filter. One object of the invention is to reduce the loss of the tunable filter to a minimum value. The use of a single crystal ferroelectric material reduces the dielectric loss of the ferroelectric material to a minimum value. The use of a single crystal dielectric material reduces its dielectric loss to a minimum. The use of a single crystal high Tc superconductor reduces the conductive loss to a minimum. Another object of the invention is (1) to obtain a single valued variable dielectric constant as a function of the biasing voltage and (2) eliminate hysteresis loss present with an a.c. biasing voltage by operating the tunable filter slightly above the Curie temperature. Another object of this invention is the ability to operate the tunable filter up to a 0.5 MW level of RF power. Another object of this invention is to obtain a reciprocal device. Another object of this invention is to obtain epitaxial deposition of a high Tc superconductor on a ferroelectric material.
Another object of the invention is to obtain a minimum dielectric loss, which is the predominant loss of the ferroelectric materials, by the use of single crystal ferroelectric and single crystal dielectric materials. Another objective is to obtain a minimum conductive loss by the use of single crystal high Tc superconductor materials.
Depending on a trade-off study in an individual case, the best type of tunable filter can be selected.
With these and other objectives in view, as will be more particularly pointed out in detail in the appended claims, reference is now made to the following description taken in connection with the accompanying diagrams.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of an embodiment of my invention.
FIG. 2 is a transverse cross-section view, through a resonator 4, of FIG. 1, the tunable band reject filter.
FIG. 3 is another transverse cross-section view, through a resonator 4, of FIG. 1, depicting another embodiment of the tunable band reject filter.
FIG. 4 depicts a top view of another embodiment of my invention, a monolithic band pass tunable ferroelectric filter.
FIG. 5 is a longitudinal cross-section view of FIG. 4 of the monolithic tunable band pass ferroelectric filter.
FIG. 6 is another longitudinal cross-section view of FIG. 4 of the monolithic tunable band pass ferroelectric filter.
FIG. 7 is a top view depicting another embodiment of my invention, a monolithic tunable ferroelectric band pass filter.
FIG. 8 depicts a longitudinal cross-section view of FIG. 7.
FIG. 9 depicts another longitudinal cross-section view of FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a top view of an embodiment of my invention. It is a film of a single crystal high Tc superconductor material, such as YBCO or TBCCO and is a part of a monolithic single crystal ferroelectric tunable band reject filter. The tunable band reject filter's main microstrip line is 1. Generally, the permittivity of the ferroelectric film 15, below the single crystal high Tc superconductor film, is high and the resulting impedance of the microstrip line 1 is low. To match the impedance of the tunable band reject filter microstrip line 1 to the impedance of an input circuit of the tunable filter, a quarter wavelength long , at an operating frequency of the tunable band reject filter, matching transformer 2 is used. For matching the impedance of the tunable band reject filter microstrip line 1 to the impedance of the output circuit of the tunable band reject filter, a quarter wavelength long, at an operating frequency of the tunable band reject filter, matching transformer 3 is used. A half wave resonator 4 is inductively coupled to the main microstrip transmission line 1 and provides a short circuit at the resonant frequency of the resonator. There is no effect off resonance. The coupling length, between the main transmission line 1 and the resonator 4, is a small percentage of the total resonator length and is adjusted to increase or decrease the bandwidth of the filter. It is inductively coupled in the middle of the resonator. The tunable band reject filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. An inductance L1 provides a high impedance at an operating frequency of the tunable filter. Any RF energy present after the inductance L1 is bypassed to the ground by the capacitor C1. A bias voltage V1 is applied to the resonator of the tunable band reject filter to change the permittivity and as such the resonant frequency of the tunable band reject filter. The input is 10 and the output is 11. The tunable filter is reciprocal. A second resonator 5 is shown in FIG. 1 which is tuned to a different or same frequency depending on the requirements of the filter. The bias filter is comprised of inductance L2 and capacitor C2. A voltage V2 is applied to the resonator 5 to change its resonant frequency. To eliminate or to reduce the interference at different frequencies, resonators tuned to different frequencies are used. Only two resonators are shown in FIG. 1, but n resonators can be used. The separation distance between the centers of the resonators is typically three quarters of a wavelength or a value determined by the requirements of the filter. The bias voltages, and thus the reject frequencies, can be independently controlled by a microprocessor whose outputs are fed to the bias voltage sources.
FIG. 2 is a transverse cross-section I--I view of the tunable band reject filter, through a resonator 4, of FIG. 1. A single crystal dielectric material, such as sapphire, is the substrate 13. On top of the substrate 13 is deposited a film 14 of a single crystal high Tc superconductor, such as YBCO or TBCCO, which is grounded. On top of the film 14 is deposited a film 15 of a single crystal ferroelectric material such as KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 where the value of x is between 0.005 and 0.7. On top of the film 15 are deposited films 1 and 4 of a single crystal high Tc superconductor material. The cross-section of the main transmission line is 1. The cross-section of the coupled resonator is 4. An inductance L1 provides a high impedance at an operating frequency of the tunable band reject filter. Any remaining RF energy is bypass to the ground by the capacitor C1. A bias voltage V1 applied to the resonator 4 of the band reject filter changes the permittivity of the ferroelectric film 15 and as such the operating frequency of the band reject filter. The tunable band reject filter is a monolithic microwave integrated circuit (MMIC).
The tunable band reject filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. Element 99 is the means to keep the tunable filter at a high superconducting temperature
FIG. 3 is another transverse cross-section, through a resonator 4, of FIG. 1, depicting another embodiment of the tunable band reject filter. A single crystal high Tc superconductor, such as YBCO or TBCCO, is the substrate 64 which is grounded. On top of the substrate 64 is deposited a film 15 of a single crystal ferroelectric material such as KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 where the value of x is between 0.005 and 0.7. On top of the film 15 are deposited films 1 and 4 of a single crystal high Tc superconductor material. The cross-section of the main transmission line is 1. The cross-section of the coupled resonator is 4. An inductance L1 provides a high impedance at an operating frequency of the tunable band reject filter. Any remaining RF is bypass to the ground by the capacitor C1. A bias voltage V1 applied to the resonator 4 of the band reject filter changes the permittivity of the ferroelectric film 15 and as such the operating frequency of the band reject filter. The tunable band reject filter is a monolithic microwave integrated circuit (MMIC). The tunable band reject filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film.
FIG. 4 depicts a top view of another embodiment of my invention, a monolithic band pass tunable ferroelectric filter. It consists of interdigital microstrip lines 21, 22, 23 comprised of a film of a high Tc superconductor material such as YBCO or TBCCO. There are 1st through nth parallel microstrip lines having a separation between the 2 nd through (n-1) th microstrip lines. The separation distance between the 1 st and 2 nd microstrip lines and the separation distance between the (n-1)th and the nth microstrip lines respectively are smaller than the separation distance between the rest of the microstrip lines. The 1 st through nth microstrip lines are separate from each other respectively. Each microstrip line is half a wavelength long at an operating frequency of the filter. The coupled lines are 24 and 25. The high Tc superconductor film is deposited on a single crystal ferroelectric film. Generally, the permittivity of a ferroelectric film is large and as such the impedance of the microstrip line is low. For matching the impedance of the input of the tunable filter to an impedance of the input circuit of the tunable filter, a quarter wavelength, at an operating frequency of the tunable filter, matching transformer 26 is used. For matching the impedance of the output of the tunable filter to an impedance of the output circuit of the tunable filter, a quarter wavelength, at an operating frequency of the filter, matching transformer 27 is used. The tunable band reject filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. Inductances L1, L2, L3, L4 and L5 provide a high impedance at an operating frequency of the tunable filter. Any RF energy present after the inductances L1, L2, L3, L4 and L5 is by passed to the ground by the capacitor C. A bias voltage V is applied to the microstrip lines of the tunable band pass filter to change the permittivity and as such the resonant frequency of the tunable band pass filter. The input is 10 and the output is 11. The tunable band pass filter is reciprocal. Only three microstrip lines are shown in FIG. 4, but n microstrip lines can be used depending on the tunable filter requirements.
FIG. 5 is longitudinal cross-section II--II of the monolithic tunable band pass ferroelectric filter. A single crystal dielectric, such as sapphire, substrate is 36. On top of the substrate 36 is deposited a film 35 of a single crystal high Tc superconductor material, such as YBCO or TBCCO, which is grounded. On top of the film 35 is deposited a film 34 of a single crystal ferroelectric material such as KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 where the value of x is between 0.005 and 0.7. On top of the film 34 of a ferroelectric material is deposited films 26, 24, 21, 22, 23, 25 and 27. The matching transformers are 26 and 27. The input matching transformer 26 cross-section is continuous with the microstrip line 24. The cross-section of the output matching transformer 27 is continuous with the microstrip line 25. The tunable band pass filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. The band pass filter is reciprocal. Cross-sections of only three microstrip lines are shown in FIG. 5, but n microstrip lines can be used depending on the tunable filter requirements. The band pass filter is a monolithic microwave integrated circuit (MMIC). Element 99 is the means to keep the tunable filter at a high superconducting temperature.
FIG. 6 is a longitudinal cross-section of another monolithic tunable band pass ferroelectric filter embodiment of FIG. 4. A single crystal high Tc superconductor material, such as YBCO or TBCCO, is the substrate 65 which is grounded. On top of the substrate 65 is deposited a a film 34 of a single crystal ferroelectric material such as KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 where the value of x is between 0.005 and 0.7. On top of the film 34 of a ferroelectric material are deposited conductive films. Elements 26, 24, 21, 22, 23, 25 and 27 are cross-sections of conductive films. The matching transformers are 26 and 27. The input matching transformer 26 cross-section is continuous with the microstrip line 24. The cross-section of the output matching transformer 27 is continuous with the microstrip line 25. The tunable band pass filter is operated at a high Tc superconducting temperature slightly above the Curie of the ferroelectric film. The band pass filter is reciprocal. Cross-sections of only three microstrip lines are shown in FIG. 6, but n microstrip lines can be used depending on the tunable filter requirements. The band pass filter is a monolithic microwave integrated circuit (MMIC).
FIG. 7 is a top view depicting another embodiment of my invention, a monolithic tunable ferroelectric band pass filter, Half wavelength, at an operating frequency of the tunable filter, parallel staggered microstrip lines, comprised of a film of a single high Tc superconductor material such as YBCO or TBCCO, are 41, 42, 43, 44 and 45. Only five poles or microstrip lines are shown for simplicity. There are n poles or microstrip lines, in a tunable band pass filter, depending on the filter requirements. Each microstrip line is a half a wavelength long at an operating frequency of the filter. 1 st through nth microstrip lines are separate from each other respectively. Underneath the films 41, 42, 43, 44 and 45 of a single crystal high Tc superconductor is a film of a single crystal ferroelectric material. Generally, the permittivity of a single crystal ferroelectric material is large. As such, the impedance of the microstrip line is low. For matching the impedance of the band pass filter input to an impedance of an input circuit of the tunable band pass filter, a quarter wavelength, at an operating frequency of the tunable filter, matching transformer 46 is used. For matching the impedance of the output of the tunable band pass filter, a quarter wavelength, at an operating frequency of the filter, matching transformer 47 is used. The tunable band pass filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. Inductances L1, L2, L3, L4 and L5 provide a high impedance at an operating frequency of the tunable filter device. Any RF energy present after the inductances L1, L2, L3, L4 and L5 is bypass to the ground by the capacitor C. A bias voltage V is applied to the microstrip lines of the tunable band pass filter to change the permittivity and as such the resonant frequency of the tunable band pass filter. The input is 10 and the output is 11. The tunable band pass filter is reciprocal.
FIG. 8 depicts a longitudinal cross-section III--III of FIG. 7. A single crystal dielectric material, such as sapphire, is the substrate 56. On top of the substrate 56 is deposited a film of a single crystal high Tc superconductor, such as YBCO or TBCCO, 55 which is grounded. On top of the film 55, is deposited a film of a single crystal ferroelectric material 54 of KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 , where the value of x is between 0.005 and 0.7. On top of the film 54 are cross-sections of films 46, 41, 42, 43, 44, 45 and 47 comprised of a single crystal high Tc superconductor material. The cross-sections of the input quarter wave transformer 46 and the half wave microstrip line are continuous. The cross-sections of the output quarter wave transformer 47 and the half wave microstrip line 45 are continuous. The tunable band pass filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. The band pass filter is reciprocal. The tunable band pass filter is a monolithic microwave integrated circuit (MMIC). Element 99 is the means to keep the tunable filter at a high superconducting temperature.
FIG. 9 depicts longitudinal cross-section of FIG. 7, in another embodiment of my invention. A single crystal high Tc superconductor, such as YBCO or TBCCO, comprises the substrate 75 which is grounded. On top of the substrate 75, is deposited a film of a single crystal ferroelectric material 54 of KTa 1-x Nb x O 3 or Sr 1-x Pb x TiO 3 , where the value of x is between 0.005 and 0.7. On top of the film 54 are cross-sections of films 46, 41, 42, 43, 44, 45 and 47 comprised of a single crystal high Tc superconductor material. The cross-sections of the input quarter wave transformer 46 and the half wave microstrip lines are continuous. The cross-sections of the output quarter wave transformer 47 and the half wave microstrip line 45 are continuous. The tunable band pass filter is operated at a high Tc superconducting temperature slightly above the Curie temperature of the ferroelectric film. The band pass filter is reciprocal. The tunable band pass filter is a monolithic microwave integrated circuit (MMIC). Each embodiment has four layers. The first layer is a sheet of a single crystal dielectric material. The second layer is a film of a single crystal high Tc superconductor, connected to an electrical ground, deposited on the sheet of the single crystal dielectric material of the first layer. The third layer is a film of a single crystal ferroelectric material deposited on the film of a single crystal high Tc superconductor of the second layer, a fourth layer is made of microstrip lines comprised of a film of a high Tc superconductor material deposited on the film of a single crystal ferroelectric material of the third layer. A bias voltage is connected between the third layer and the microstrip line(s) of the first layer.
It should be understood that the foregoing disclosure relates to only typical embodiments of the invention and that numerous modification or alternatives may be made therein by those of ordinary skill in art without departing from the spirit and the scope of the invention as set forth in the appended claims. Specifically, the invention contemplates various dielectrics including sapphire, lanthanum aluminate, ferroelectrics, ferroelectric liquid crystals (FLCs), high Tc superconducting materials including YBCO, TBCCO, impedances, MMICs, tunable filter configurations, layers of filter devices, operating bias voltage of the filters, number of resonators and frequencies. | This invention pertains to monolithic filters of the band-pass or band-reject type which a single crystal ferroelectric material having an electric field dependent permittivity. The filters are comprised of: a first layer of a single crystal dielectric material; a second layer of a single crystal high T c superconductor material; a third layer of a single crystal ferroelectric material; and a fourth layer of high T c superconductive microstrip lines configured into the various filter circuits, including resonator circuits and transformer circuits. The filters are capable of operating at power levels up to 0.5 MW at a temperature slightly above the Curie temperature to avoid hysteresis. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] N/A
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
COPYRIGHT NOTICE
[0003] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure as it appears in the United States Patent and Trademark Office patent file or records, but otherwise reserves all copyrights whatsoever.
BACKGROUND
[0004] (1) Field of the Invention
[0005] Relating to improvements in training mechanisms used in exercise regimens for both men and women. More specifically, relating to improvements in devices utilizing a pace setting aid.
[0006] (2) Existing Technologies
[0007] There are many computer based pace setting equipment in existence that time the movements of persons in various sports. Optical measuring devices capture the movement of athletes and translate the detected data into pace setting and measuring outputs. However, the inclusion of computers, sensors and auxiliary equipment is expensive and cumbersome. Thus, what is needed is a simple device that can easily facilitate setting and maintaining the pace of exercises in an inexpensive and simple fashion.
BRIEF SUMMARY OF THE INVENTION
[0008] A cylindrical pace setting device having a cavity filled by a door at a base region forming a space for adhesion of circuit elements at the interior surface of an enclosed region (top interior, bottom interior, interior walls); at the opposite side of the door is a circular top wall that has a small central opening for insertion of a switch. A Velcro activated cuff is connected to the back of the cylinder. The device has multiple springs connected between the cylinder and the piece of material holding the piece of material and the cylinder together. The piece of material serves as a large touching zone for athletic pace setting. A row of LEDs arranged within cavities that perforate the surface of the circular cylindrical wall are lighted by a battery having a snap terminal connected to the first jumper connection and a push button device operable to activate the lighting circuit. The first jumper connection is connected to two resistors that are respectively connected to two sets of differently colored LEDs and a second jumper connection having connections to both sets of LEDs and the push button device.
[0009] The internal parts are glued, taped, arranged in molded plastic slots, bolted (nut and bolt), snap-in plastic part moldings or combinations of the foregoing. Further, the springs are connected to the piece of material and to the cylinder's top circular slab that has been integrated with a circular wall and an enclosed region therein. The springs can be glued, taped, the ends of each inserted in slots for holding it in place or combinations of the foregoing.
[0010] The large piece of material is a hemisphere or similar type of surface for easy accessibility during athletic training. In particular, the hemisphere is a representation of a sports item so as to situate the item in the particular field where training occurs such as soccer, basketball or similar sports. Additionally, the piece of material is substantially similar to the size of the enclosed region of the cylinder, in other words, of a size that it is of nearly the same size as the enclosed region as practical.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] FIG. 1 illustrates the application of an embodiment as applied to the legs of an athlete showing various features.
[0012] FIG. 2 illustrates various external and internal structures of an embodiment as taught herein.
[0013] FIG. 3 illustrates an electrical circuit overview showing various electrical components of an embodiment.
[0014] FIG. 4 illustrates an electrical circuit diagram of an embodiment showing the interrelation between various electronic parts.
[0015] FIG. 5 illustrates an electrical circuit overview showing various other features of electrical components of an embodiment.
[0016] FIG. 6 illustrates various connection schemes used in an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The following is a detailed description of the preferred embodiment with respect to FIGS. 1-5 .
[0018] FIG. 1 illustrates the application 100 of an embodiment as applied to the legs of an athlete showing various features. A (plastic, non-rigid or foam) hemisphere 110 of material is attached through the use of several glued springs 120 to a wide top surface 130 (PVC or similar material); this serves as a top portion for a reversed (PVC or similar plastic) cylinder 140 that has a hollow internal area for insertion of electrical components. The springs 120 are glued to the top 130 of the hollow cylinder 140 . Alternatively the springs' ends are threaded into corresponding slots that are found at the top of the hollow cylinder 140 . Similarly, the springs 120 are either glued or connected to the underside of the hemisphere (plastic, non-rigid or foam) using corresponding slots. The cylinder 140 has two banks of LED lights 150 alternatively RED and WHITE that are placed in a plurality of cavities arranged around the circumference of the cylinder 140 such that the cavities perforate the cylinder allowing for each of the LEDS 150 to be in electrical connection with other components of the circuit as taught below. An attachment cuff(s) 160 made of a generic material such as polyester, cotton, spandex or similar material is shown having VELCRO material sewn into or otherwise attached to it in a conventional fashion. VELCRO is a brand name of fabric hook-and-loop fasteners; the cuff 160 has a matching set ( 170 , 180 ) arranged on an external side of the cuff 170 and on an inner side 180 of the cuff 160 so as to enable engagement of the VELCRO material by user interaction with the cuff placing one over the other. The cuff 160 is attached to the external face of the bottom side of the cylinder 140 through the use of glue; alternatively plastic bolt and nut combination perforating the bottom of the cylinder will accomplish the same.
[0019] FIG. 2 illustrates various external and internal structures of an embodiment as taught herein. The top surface 200 of cylinder 220 is as shown in FIG. 2A . Just below the top surface 200 is a row of red and white LED lights 210 extending from the inside of the cylinder through the cylinder material and breaching the outside surface of the cylinder 220 so as to provide a light indication as discussed below. Springs 230 are glued or inserted in slots on the top surface 200 of the cylinder and at the bottom side of hemisphere 240 . The bottom surface of the hemisphere 240 is in contact with a push button switch 250 that is utilized to practice the invention. The switch 250 is situated in a hole central to the top surface slab and between the springs; it can be glued or taped to the slab 200 . When a user pushes down upon the surface of the hemisphere 240 it presses down upon the top surface of the push button switch that slides down upon application of sufficient pressure to the top of the hemisphere. The pushbutton switch thus enables the activation of the banks of LED lights 210 through the use of electronic circuitry described in further detail in FIGS. 3-5 . FIG. 2B shows a top down view of the symmetrical arrangement of four springs 230 about the center where the push button switch is centrally located. Similarly, when user pressure is no longer applied to the hemisphere 240 the springs push back upon it and the hemisphere moves upwards and as a consequence the switch 250 returns to its off position; as a result, the LED lights 210 are deactivated. FIG. 2C shows a hinged door 270 arrangement and mechanical clasp 280 that closes the enclosed region within the cylinder. FIG. 2D shows an outer door 290 that is taped or glued in place forming an enclosed space in the cylinder for the storage of electrical components. FIG. 2E shows a typical push button part for the circuit. FIG. 2F shows a typical taping arrangement for the circuit.
[0020] FIG. 3 illustrates an electrical circuit overview showing various electrical components of an embodiment. A half dozen red 300 and a half dozen white 310 LEDs are arranged in a circle about the cylinder previously described. FIG. 3 only shows how these components are arranged about the surface of the cylinder not their specific electrical connections; that will be shown with respect to FIGS. 4-5 . Jumper interconnects 320 and 330 are shown having three connection points and realized in WAGO part #859-403. A push button switch 340 is shown schematically as radio shack part #275-1547 that is used to make electrical connection and complete the circuit. A 9V battery 350 and snap-on battery terminal 360 are shown in the figure as ULTRALAST/PART #55039849 and RADIO SHACK/PART #270-325. The 9V battery serves as the only power source for the LOW GLOW device. When applied to the inner cylinder enclosed space, the various electrical components disclosed herein are taped or glued according to the wiring circuitry layout of FIGS. 3-4 in a convenient fashion according to the implementation. The walls of the cylinder, underneath, i.e., inside of the top slab and the bottom region (door or door edge area) may also be used to tape the devices herein.
[0021] FIG. 4 illustrates an electrical circuit diagram of an embodiment showing the interrelation between various electronic parts. A three-connection jumper WAGO part #859-403 node 400 connects three circuit legs in parallel. The first leg connects through a load resistor 410 herein shown as a 100 ohm resistor RADIO SHACK/PART 271-1108 that connects to a set 430 of six RADIO SHACK/PART 276-017 WHITE LEDs; this set 430 is itself an arrangement of parallel LEDs as shown in the drawings. Typically, the LEDS are 25 mA rated LEDS and are finally connected to another three connection jumper 450 interconnect WAGO part #859-403. In a similar fashion the second leg of the circuit connected to jumper interconnect 400 has a current limiting resistor 420 herein shown as a 330 ohm resistor RADIO SHACK/PART 271-1113 that connects to a set 440 of six RADIO SHACK/PART 276-026 RED LEDs; this set 440 is itself an arrangement of parallel LEDs as shown in the drawings. Typically, the LEDS are 28 mA rated LEDS and are finally connected to another three connection jumper 450 interconnect WAGO part #859-403. The final leg of the circuit has a push button 460 connected in series with a 9 Volt battery as shown. When a user applies pressure to the hemisphere of material the pushbutton is depressed, as a consequence it activates the circuit described above. Current flows from the battery through the two banks of LEDS lighting up the area around the external part of the hollow cylinder previously described. Thus, this light indicates to a user that a particular pace is being kept and so an instructor or group of athletes can maintain timing during an exercise regimen. When a user releases the pressure on the hemisphere of material the springs push back on the hemisphere returning it to its original location. In this fashion, the push button switch is no longer in the active position and current ceases to flow in the circuit and as a consequence the lights turn off.
[0022] FIG. 5 illustrates an electrical circuit overview showing various other features of electrical components of an embodiment. FIG. 5A illustrates how the Red LEDs cathodes are arranged together and how the Red anodes are arranged together. FIG. 5A indicates that the White LEDs cathodes and anodes are arranged together like their red counterparts. Once the red and white LEDs are connected in parallel with conventional electrical wiring the individual lights are placed inside the cavities along the inner surface of the cylinder. Each of the lights exits its respective cavity just enough so as to be visible externally; they are arranged so as to alternate white red white to red about the cylinder; to finish off the attachment of the device, glue and or tape hold the electric wiring and LEDs to the inner surface of the cylinder. FIG. 5B illustrates how a pushbutton switch has connections both to the 9V power source and jumper interconnection 450 . FIG. 5C illustrates how jumper interconnection 400 has three connection devices from the battery, the 330 ohm and 100 ohm resistors. Similarly, FIG. 5D shows how jumper interconnection 450 has three connection devices from the pushbutton 460 , from the last RED LED in the circuit and from the last WHITE LED in the circuit. FIG. 5E shows a typical 9V power source 470 , 350 having a snap-on connection 360 . The snap-on connector as its name implies snaps-on to the terminals of the battery; the other terminals of the connector 360 go to the pushbutton 460 and to the jumper interconnection 400 .
[0023] FIG. 6 shows various attachment mechanism used in various implementations. The first view 600 has an item (power supply and snap connector) glued 605 to the inner surface of the cylinder. It may also be taped or located on the internal bottom surface (door or door edge area) or inner top of the cylinder. The next view 610 shows how the LEDs are wired by skipping one LED in between whereby the electric wiring between each member of a set is taped 615 to the wall of the inner cylinder. The next view 620 has a plastic slot 625 for the push button whereby physical snap-in effects the connection. The plastic slot is molded right out of the internal piece of the cylinder or is itself glued to the inner surface. The next view 630 shows the end of spring can be loaded into a small notch or hole and glued therein 635 . The next view 640 shows how in one implementation bolt(s), nut(s) and or glue 645 are used to connect the cuff member(s) to the internal and external surface of the cylinder bottom. In this particular, implementation the cuff member is divided into two pieces with Velcro hooks and loops located on a different one and corresponding appropriate sides of the two pieces. Glue and or bolt fasteners hold the cuff pieces to the backside of the cylinder as shown. A door opens and closes between them facilitating access to the internal electrical parts. Optionally, one cuff may be laid across the back of the device.
[0024] The two jumper interconnects, battery and terminal are glued and or taped to the inner bottom, sides and or top of the cylinder depending upon the needs of the implementation. The push button switch is situated in a hole and is glued and or taped to the center interior top of the cylinder; alternatively, a slot is provided with a metal threading to ensure the fit of the device. Other connection schemes have any of the various parts internal to the cylinder being designed to be glued and or taped and or screwed in a metal sheath, placed in molded slots with a mechanical connection either through glue, physical compression with a plastic ‘snap-in’ effect whereby the plastic or metal holder expands to hold the device and then snaps on to a particular item, or bolt and nut type connection or combinations of the foregoing. However, the preferred system is gluing the various devices to internal surfaces and taping them for a good fit. The entire LOW-GLOW device is designed to be worn on the leg or the arm either as a single device or with a duplicate device on the other limb. The hemisphere of (plastic, non-rigid or foam) material is a representation of a sports item such as a soccer ball or basketball.
[0025] The invention has thus been described in such clear and precise terms as to enable one of ordinary skill in the art to understand its fundamental principles. | A pace setting device having a cylinder, top circular slab, a circular wall, an enclosed region; a piece of material connected at the top circular slab and a cuff at the cylinder base. The device has multiple springs connected between the cylinder and the piece of material holding the piece of material and the cylinder together. The piece of material serves as a large touching zone for athletic pace setting. A row of LEDs arranged within cavities that perforate the circular cylindrical wall are lighted by a battery having a snap terminal connected to a first jumper connection and a push button device operable to activate a lighting circuit made of the row. The first jumper connection is connected to two resistors that are respectively connected to two sets of differently colored LEDs and a second jumper connection having connections to both sets of LEDs and the push button device. | 0 |
This patent application is a continuation-in-part application of U.S. patent application Ser. No. 08/391,705 filed on Feb. 21, 1995, which will issue to U.S. Pat. No. 5,614,258 on Mar. 25, 1997.
FIELD OF THE INVENTION
The present invention relates to a method of growing diamonds by reduction of C 70 Buckminster fullerenes in the presence of diamond seed particles.
BACKGROUND OF THE INVENTION
Diamond, being the hardest substance known, is of great commercial and scientific value. It is inert to chemical corrosion and can withstand compressive forces and radiation. It is an electrical insulator having extremely high electrical resistance but is an excellent thermal conductor, conducting heat better than most other electrical insulators. Diamond is structurally similar to silicon but is a wide-band-gap semiconductor (5 eV) and so is transparent to UV-visible light and to much of the infrared spectrum. It has an unusually high breakdown voltage and low dielectric constant. These properties, coupled with recent advances, have led to speculation that diamond might find widespread application in high speed electronic devices and devices designed to be operated at high temperature. If it can be doped successfully diamond could become an important semiconductor material on which new or replacement device applications may be based. While silicon chips can withstand temperatures up to 300° C., it is estimated that diamond devices may be able to withstand considerably higher temperatures. Diamond film already find applications as hard protective coatings.
Because of these useful properties, synthetic diamond has great potential in research and commercial applications. Synthetic diamonds are now produced by two known methods: a high pressure process in which carbonaceous material is compressed into diamond using high pressure anvils; and the more recent technique of chemical vapour deposition (CVD) in which diamond films are deposited on an appropriate substrate by decomposing a carbon containing gaseous precursor.
Of recent particular scientific interest are a class of carbon structures known as Buckminster fullerenes which are formed by an integral number of carbon atoms which combine to form a closed, roughly spherical structure. Two prominent fullerenes are C 60 and C 70 , which are spherical structures comprising 60 and 70 carbon atoms, respectively. The successful transformation of C 60 and C 70 into diamond at high pressure has been disclosed by Manuel Nunez Regueiro, Pierre Monceau, Jean-Louis Hodeau, Nature, 355, 237-239 (1992) and Manuel Nunez Regueiro, L. Abello, G. Lucazeau, J. L. Hodeau, Phys. Rev. B, 46, 9903-9905 (1992). The transition of C 60 to diamond has also been studied by Hisako Hirai, Ken-ichi Kondo and Takeshi Ohwada, Carbon, 31, 1095-1098 (1993). It is also known that C 70 can accelerate the nucleation of diamond thin film formation on metal surfaces using CVD as disclosed by R. J. Meilunas, R. P. H. Chang, S. Liu, M. M. Kappes, Appl. Phys. Lett., 59, 3461-3463 (1991), and R. J. Meilunas, R. P. H. Chang, S. Liu, M. M. Kappes, Nature, 354, 271 (1991).
A high growth rate of diamond film using fullerene precursors in an argon microwave plasma with or without hydrogen has been reported by D. M. Gruen, S. Liu, A. R. Krauss and X. Pan, J. Appl. Phys., 75,1758-1763 (1994), and D. M. Gruen, S. Liu, A. R. Krauss, J. Luo and X. Pan, Appl. Phys. Lett., 64, 1502-1504 (1994).
Recently, dispersed diamond particles with diameters in the range of 20-150 Å have been observed in fullerene-rich soot as disclosed by Vladimir Kuznetsov, A. L. Chuvilin, E. M. Moroz, V. N. Kolomiichuk, Sh. K. Shaikhutdinov, Yu. V. Butenko, Carbon, 32, 873-882 (1994), and Vladimir L. Kuznetsov, Andrey L. Chuvilin, Yuri V. Butenko, Igor Yu. Malkov, Vladimir M. Titov, Chem. Phys. Lett., 222, 343-348 (1994).
U.S. Pat. Nos. 5,370,855, 5,462,776, 5,328,676 and 5,209,916 issued to Gruen disclose methods of conversion of fullerenes to diamond. The methods comprise subjecting the fullerenes to highly energetic environments such as radio frequency plasma discharges, electron beams, intense laser beams to break down potassium modified fullerenes. Growth of diamond onto diamond seed substrates heated to 1000° to 1200° C. is disclosed in U.S. Pat. No. 5,462,776. A drawback to all these methods of fullerene conversion is the fact that at such high temperatures the diamond structure is prone to conversion to graphite. Another drawback is the expense of the energy imparting devices such as lasers, RF generators and the like.
It would be very advantageous and of potentially significant commercial value to be able to grow single crystal diamond particles with much larger particle sizes at relatively low temperatures in an environment not requiring capital intensive equipment.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an economical process for growing single crystal diamonds which does not require high temperatures or pressures.
The present invention provides a process for the formation of diamond particles of mean diameters in excess of 4.0×10 -4 m, grown from diamond powder nucleation seeds of approximately 1.5×10 -6 m mean diameter. C 70 is reduced in the presence of reducing agents such as selenium or phosphorous at moderate temperatures and pressure.
In one aspect of the invention there is provided a process for growing diamonds comprising exposing diamond seed particles to vapour phase C 70 in the presence of an element selected from the group consisting of selenium and phosphorous at a temperature of at least 550° C. to cause at least some of the diamond seed particles to grow.
In another aspect of the invention there is provided a process for growing diamonds. The process comprises providing a plurality of diamond seed particles; providing a quantity of C 70 powder and an element selected from the group consisting of selenium and phosphorous, the C 70 and powder and the element being in flow communication with the diamond seed particles; and heating the C 70 powder to produce C 70 powder in vapour phase, and heating the element and the diamond seed particles at a temperature of at least 500° C. and for a period of time of from 18 days to 60 days to cause at least some of the diamond seed particles to grow.
In another aspect of the invention there is provided a process for growing diamonds. The process comprises providing a plurality of diamond seed particles having a mean diameter and providing a quantity of C 70 powder and a reducing agent. The C 70 powder and the reducing agent are in flow communication with the diamond seed particles. The process includes the step of heating the C 70 powder to produce C 70 in the vapour phase, and heating the reducing agent and the diamond seed particles under vacuum at a temperature of from about 500° C. to about 600° C. and for a period of time of from about 18 days to about 60 days to cause a portion of the C 70 in the vapour phase to be reduced by the reducing agent and deposit onto and increase the mean diameter of at least one of the diamond seed particles.
The present invention also provides a process for growing diamonds comprising exposing diamond seed particles to vapour phase C 70 in the presence of a gas phase metal carbonyl at an effective temperature to cause at least some of the diamond seed particles to grow. The gas phase metal carbonyl is preferably on of the iron carbonyls and most preferably iron penta-carbonyl.
The invention also provides a process for growing diamonds comprising exposing diamond seed particles to vapour phase C 70 in the presence of a gas phase catalyst comprising at least CO constituent at an effective temperature to cause at least some of the diamond seed particles to grow. The catalyst is preferably Fe(CO) 5 .
In another aspect the present invention provides a process for growing diamonds comprising exposing said diamond seed particles to vapour phase C 70 in the presence of a gas phase iron carbonyl at a temperature in the range from about 570° C. to about 600° C. to cause at least some of the diamond seed particles to grow. The iron carbonyl is preferably Fe(CO) 5 .
BRIEF DESCRIPTION OF THE DRAWINGS
The method of diamond growth from C 70 forming the subject invention will now be described, reference being had to the accompanying drawings, in which:
FIG. 1 illustrates an apparatus used for growing diamonds from diamond seeds according to the present invention;
FIG. 2 is a scanning electron micrograph (SEM) of C 70 polycrystalline powder used in the method according to the present invention;
FIG. 3 is an SEM of a sample of the diamond seeds (average size ˜1.5 μm) used in the method of the present invention;
FIG. 4 is an SEM of several diamond particles found in the lower portion of the capillary shown in FIG. 1 after the assembly was heated at 550° C. for 20 days in the presence of selenium;
FIG. 5 displays a typical laser micro-Raman spectrum of the C 70 polycrystalline powder of FIG. 2;
FIG. 6 displays a laser micro-Raman spectrum of one of the particles shown in FIG. 4 in the wavelength range 1000 to about 1700 cm -1 ;
FIG. 7 displays a laser micro-Raman spectrum of one of the particles shown in FIG. 4 in the wavelength range 500 to about 1700 cm -1 ;
FIG. 8 is shows the x-ray diffraction of one of the grown diamond particles shown in FIG. 4;
FIG. 9 shows the structure of a diamond particle grown according to the method of the present invention calculated from the x-ray diffraction pattern of FIG. 8;
FIG. 10 shows the structure of C 70 ; and
FIG. 11 shows the structure of C 60 .
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, approximately 18 to 20 mg of C 70 (98%), approximately 11 mg of elemental selenium powder (99.5%, -325 Mesh particle size, Alfa) or red phosphorous powder (99%, -100 Mesh particle size, Alfa) and trace quantities of diamond seed powder (average diameter of 1.5×10 -6 m) were placed generally at 10 in a 1 cm diameter×10 cm long pyrex tube 12. A trace quantity (<1 mg) of diamond powder shown generally at 14 was loaded into a small pyrex capillary (1.0 mm×50 mm) 16, which was then set into the larger pyrex tube 12 as shown in FIG. 1. The entire tube assembly was evacuated and sealed under vacuum of approximately 2.66×10 -2 Pascals (˜2×10 -5 torr). After heating the tube assembly at a temperature of about 550° C. in a tube oven (not shown) with controllable temperature for 20 to 30 days, various portions of the product were examined using laser micro-Raman Spectroscopy and scanning electron microscopy (SEM).
Crystallite sizes and shapes of the diamond seeds and the reaction produces were examined using scanning electron microscopy (HITACHI model S-570, Japan). The identification of the crystallites as diamond was accomplished using Laser micro-Raman spectroscopy. An important advantage of micro-Raman spectroscopy is that the sample crystallite can be located by a charge coupled device (CCD) camera at high magnification. This enabled both the size of the crystallite and its identity to be determined simultaneously. A Kr ion laser tuned to 530.87 nm was used as the excitation source. An approximately 2 mW beam was focused down to a 3 micrometer diameter spot. Raman spectra were detected in a back scattering geometry using a triplemate spectrometer (SPEX Industries Inc. model 1877D) equipped with a microscope (Micromate model 1482D) and a liquid nitrogen cooled CCD detector (Princeton Instruments Inc. Model LN/CCD).
An SEM image of the C 70 powder that was used in the above-described experiment is shown in FIG. 2. The plate-like crystallites are shown for the purpose of comparison with diamond crystallites. FIG. 3 shows an SEM image of a sample of the diamond powder that was used as seed diamond. Examination of several such samples showed that particle diameters rarely exceeded 2×10 -6 m and no particle with a diameter in excess of 3×10 -6 m was seen. In contrast, FIG. 4 shows four crystallites with average diameters of approximately 400 μm that were found among the reaction products of the fullerene seeded with small diamond particles and with selenium used as the reducing or reacting agent after 20 days of heating at 550° C. Only approximately 1% of the diamond seeds were found to be enlarged to this extent. However, on a volume basis the overall enlargement of the individual seeds was substantial.
The micro-Raman spectrum of one of these crystallites is shown in FIG. 6 over the wavelength range 1000 to about 1700 cm -1 . The characteristic single peak at approximately 1328 cm -1 is unequivocal proof that the particle is diamond. The micro-Raman spectrum shown in FIG. 7 is similar to the spectrum of FIG. 6 but was taken in the wavelength range 500 to about 1700 cm -1 . For comparison, the Raman spectrum of C 70 that was used in this work is shown in FIG. 5. There is no such peak at 1328 cm -1 . The 26 relatively strong vibrational mode frequencies obtained from the spectrum of FIG. 5 are in good agreement with values previously disclosed in R. A. Jishi, M. S. Dresselhaus, G. Dresselhaus, Kai-An Wang, Ping Zhou, A. M. Rao and P. C. Eklund, Chem. Phys. Lett., 206, 187 (1993). These vibrational mode frequencies are also in good agreement with group theoretical analysis, see M. S. Dresselhaus, G. Dresselhaus and R. Saito, Phys. Rev. B, 45, 6234 (1992). In all C 70 has 53 Raman active modes.
The x-ray diffraction pattern shown in FIG. 8 for one of the grown diamond particles in FIG. 4 clearly shows the single crystal cubic structure of diamond and this is confirmed from the crystal structure shown in FIG. 9 calculated from the x-ray diffraction pattern of FIG. 8.
Most of the larger diamond particles that were produced were found in the capillary 16 (FIG. 1) in which the seed diamonds were deposited. This strongly suggests that gas-phase C 70 was responsible for the growth of the seed diamonds. C 70 has a substantial vapour pressure at 550° C. The Raman spectrum of the material that remained at the bottom of the larger tube 10 after 20 days corresponded to that of unreacted C 70 .
Analogous experiments were also conducted using C 60 instead of C 70 . These experiments using C 60 did not produce any measurable growth in the size of the diamond seed particles based on comparison of SEMs taken before and after prolonged exposure of the seeds to C 60 under essentially the same conditions of temperature, pressure and time as with the C 70 .
In addition to selenium and phosphorous, other elemental reducing agents such as sodium, potassium and sulphur are contemplated by the inventors to be effective in reducing C 70 and at temperatures higher than in the range 500° to 600° C.
The following is a possible growth mechanism proposed by the inventors. The mechanism is speculative, so it will be understood that the following is meant to be a non-limiting explanation. The structure of C 70 is shown generally at 40 in FIG. 10 and can be compared to the structure of C 60 shown at 70 in FIG. 11. The carbon atoms 42 comprising C 70 are hybridized intermediately between sp 2 (as in graphite) and sp 3 , the hybridization of carbon in diamond. When one of the bonds is broken in a fullerene, the two carbons comprising the broken bond have a choice between sp 2 and sp 3 hybridization according to the nature of the reaction partner that reacts at the broken bond. Referring to FIG. 11, C 60 has two types of C--C bonds; a so-called "single bond" 44 at the edges between pentagonal and hexagonal faces, and a "double bond" 46 at the edges between hexagonal faces. However, all carbon atoms are vertices of both hexagonal and pentagonal faces. Referring to FIG. 10, C 70 has, additionally, C--C bonds 50 that are edges separating two hexagonal faces and, also, vertices of hexagonal faces only. The inventors speculate that it is these additional carbon-carbon bonds 50 in C 70 that break to initiate diamond growth.
It is speculated that the diamond seed acts as a template whose surface dangling bonds ensure that the carbon atoms of the newly ruptured C--C bond of the C 70 molecule adopt the sp 3 hybridization required to continue the diamond growth. Ultimately all of the carbon atoms of the C 70 molecule could be incorporated into the diamond.
Metal carbonyls also exhibit an efficacy as catalysts for producing single crystal diamonds from C 70 . In one study, 110 mg of C 70 a was placed in a glass capillary tube together with a small quantity of 1-3 μm mean diameter diamond powder which had previously been cleaned with ether, acetone, methanol, acetonitrile, toluene, acetone, water, nitric acid, HCl and water. The tube was evacuated and distilled iron carbonyl (Fe(CO) 5 ) was introduced to the level of the room temperature vapor pressure. The tube was sealed and baked at 580° C. for 150 days. Twelve diamond particles were recovered from the cell, each in excess of 0.1 mm mean diameter. These particles were identified as diamond using Raman spectroscopy and x-ray crystallography. Other metal carbonyls than iron also exhibit catalytic properties for growth of diamond from C 70 in addition to iron carbonyls other than the penta-carbonyl. The inventors reasonably believe the metal carbonyl is acting as a source of CO which may also be acting to catalyse diamond growth.
The present process is very advantageous since gem diamonds may be grown under low pressures and low temperatures for example in the range from about 400° C. to about 700° C. As discussed above, prior art methods for growing diamonds involve very high pressures and temperatures or expensive equipment for generating various kinds of energetic environments. The present method provides a very economical method of growing diamonds.
Although the process in accordance with the present invention occurs at relatively low temperatures and pressures, it makes use of the free energy stored in the C 70 molecule during its formation at the very high temperatures of the carbon arc used to generate it. This increase in free energy (over that of the graphite precursor in the form of the electrodes of the arc) manifests itself in the intermediate hybridization characteristic of the fullerenes. Recent theory predicts the involvement of a non-planar intermediate which has one sp 3 and one sp hybridized carbon, see Robert L. Murray, Douglas L. Strout, Gregory K. Odom and Gustavo E. Scuseria, Nature, 366, 665-667 (1993).
In order to channel this free energy into diamond formation some of the C--C bonds in C 70 , must be induce to rupture. This is achieved by the presence of materials such as selenium, phosphorous and the carbonyl catalysts containing CO that donate electrons to the C 70 and, therefore, facilitate bond breaking.
The present invention advantageously provides an economical method of growing diamonds from seed diamond particles with C 70 which does not require high pressures or temperatures as in the known methods. The result that C 70 , but not C 60 , can be readily reduced in the presence of a reducing agent was completely unexpected. | A method of growing single crystal diamonds in excess of 10 μm in diameter from industrial diamond "seeds" having mean diameters of approximately 1.5 μm is disclosed. The diamonds are grown by exposing the seed diamonds to C 70 in the presence of elemental reducing agents such as phosphorus or selenium in evacuated cells at moderate temperatures and pressures. In another aspect the invention diamonds are grown by exposing diamond seed particles to vapour phase C 70 in the presence of a gas phase metal carbonyl, such as F 5 e(CO) in a temperature range of 400° C. to 700° C. to cause at least some of the diamond seed particles to grow. | 2 |
RELATED APPLICATION DATA
[0001] This application is a continuation of PCT application no. PCT/US2013/075317, designating the United States and filed Dec. 16, 2013; which claims the benefit U.S. Provisional Patent Application No. 61/779,169, filed on Mar. 13, 2013 and U.S. Provisional Application No. 61/738,355, filed on Dec. 17, 2012; each of which are hereby incorporated by reference in their entireties.
STATEMENT OF GOVERNMENT INTERESTS
[0002] This invention was made with government support under P50 HG005550 awarded by National Institutes of Health. The government has certain rights in the invention.
BACKGROUND
[0003] Bacterial and archaeal CRISPR systems rely on crRNAs in complex with Cas proteins to direct degradation of complementary sequences present within invading viral and plasmid DNA (1-3). A recent in vitro reconstitution of the S. pyogenes type II CRISPR system demonstrated that crRNA fused to a normally trans-encoded tracrRNA is sufficient to direct Cas9 protein to sequence-specifically cleave target DNA sequences matching the crRNA (4).
SUMMARY
[0004] The present disclosure references documents numerically which are listed at the end of the present disclosure. The document corresponding to the number is incorporated by reference into the specification as a supporting reference corresponding to the number as if fully cited.
[0005] According to one aspect of the present disclosure, a eukaryotic cell is transfected with a two component system including RNA complementary to genomic DNA and an enzyme that interacts with the RNA. The RNA and the enzyme are expressed by the cell. The RNA of the RNA/enzyme complex then binds to complementary genomic DNA. The enzyme then performs a function, such as cleavage of the genomic DNA. The RNA includes between about 10 nucleotides to about 250 nucleotides. The RNA includes between about 20 nucleotides to about 100 nucleotides. According to certain aspects, the enzyme may perform any desired function in a site specific manner for which the enzyme has been engineered. According to one aspect, the eukaryotic cell is a yeast cell, plant cell or mammalian cell. According to one aspect, the enzyme cleaves genomic sequences targeted by RNA sequences (see references (4-6)), thereby creating a genomically altered eukaryotic cell.
[0006] According to one aspect, the present disclosure provides a method of genetically altering a human cell by including a nucleic acid encoding an RNA complementary to genomic DNA into the genome of the cell and a nucleic acid encoding an enzyme that performs a desired function on genomic DNA into the genome of the cell. According to one aspect, the RNA and the enzyme are expressed, According to one aspect, the RNA hybridizes with complementary genomic DNA. According to one aspect, the enzyme is activated to perform a desired function, such as cleavage, in a site specific manner when the RNA is hybridized to the complementary genomic DNA. According to one aspect, the RNA and the enzyme are components of a bacterial Type II CRISPR system.
[0007] According to one aspect, a method of altering a eukaryotic cell is providing including transfecting the eukaryotic cell with a nucleic acid encoding RNA complementary to genomic DNA of the eukaryotic cell, transfecting the eukaryotic cell with a nucleic acid encoding an enzyme that interacts with the RNA and cleaves the genomic DNA in a site specific manner, wherein the cell expresses the RNA and the enzyme, the RNA binds to complementary genomic DNA and the enzyme cleaves the genomic DNA in a site specific manner. According to one aspect, the enzyme is Cas9 or modified Cas9 or a homolog of Cas9. According to one aspect, the eukaryotic cell is a yeast cell, a plant cell or a mammalian cell. According to one aspect, the RNA includes between about 10 to about 250 nucleotides. According to one aspect, the RNA includes between about 20 to about 100 nucleotides.
[0008] According to one aspect, a method of altering a human cell is provided including transfecting the human cell with a nucleic acid encoding RNA complementary to genomic DNA of the eukaryotic cell, transfecting the human cell with a nucleic acid encoding an enzyme that interacts with the RNA and cleaves the genomic DNA in a site specific manner, wherein the human cell expresses the RNA and the enzyme, the RNA binds to complementary genomic DNA and the enzyme cleaves the genomic DNA in a site specific manner. According to one aspect, the enzyme is Cas9 or modified Cas9 or a homolog of Cas9. According to one aspect, the RNA includes between about 10 to about 250 nucleotides. According to one aspect, the RNA includes between about 20 to about 100 nucleotides.
[0009] According to one aspect, a method of altering a eukaryotic cell at a plurality of genomic DNA sites is provided including transfecting the eukaryotic cell with a plurality of nucleic acids encoding RNAs complementary to different sites on genomic DNA of the eukaryotic cell, transfecting the eukaryotic cell with a nucleic acid encoding an enzyme that interacts with the RNA and cleaves the genomic DNA in a site specific manner, wherein the cell expresses the RNAs and the enzyme, the RNAs bind to complementary genomic DNA and the enzyme cleaves the genomic DNA in a site specific manner. According to one aspect, the enzyme is Cas9. According to one aspect, the eukaryotic cell is a yeast cell, a plant cell or a mammalian cell. According to one aspect, the RNA includes between about 10 to about 250 nucleotides. According to one aspect, the RNA includes between about 20 to about 100 nucleotides.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIGS. 1A-1C depict genome editing in human cells using an engineered type II CRISPR system. (A) sets forth SEQ ID NO:17; (B) sets forth SEQ ID NO:18.
[0011] FIGS. 2A-2F depict RNA-guided genome editing of the native AAVS1 locus in multiple cell types. (A) sets forth SEQ ID NO:19; (E) sets forth SEQ ID NOs:20 and 21.
[0012] FIGS. 3A-3C depict a process mediated by two catalytic domains in the Cas9 protein. (A) sets forth SEQ ID NO:22; (B) sets forth SEQ ID NO:23; (C) sets forth SEQ ID NOs:24-31.
[0013] FIG. 4 depicts that all possible combinations of the repair DNA donor, Cas9 protein, and gRNA were tested for their ability to effect successful HR in 293 Ts.
[0014] FIGS. 5A-5B depict the analysis of gRNA and Cas9 mediated genome editing. (B) sets forth SEQ ID NO:19.
[0015] FIGS. 6A-6B depict 293T stable lines each bearing a distinct GFP reporter construct. (A) depicts sequences set forth as SEQ ID NOs; 32-34.
[0016] FIG. 7 depicts gRNAs targeting the flanking GFP sequences of the reporter described in FIG. 1B (in 293 Ts).
[0017] FIGS. 8A-8B depict 293T stable lines each bearing a distinct GFP reporter construct. (A) depicts sequences set forth as SEQ ID NOs; 35-36.
[0018] FIGS. 9A-9C depict human iPS cells (PGP1) that were nucleofected with constructs. (A) sets forth SEQ ID NO:19.
[0019] FIGS. 10A-10B depict RNA-guided NHEJ in K562 cells. (A) sets forth SEQ ID NO:19.
[0020] FIGS. 11A-11B depict RNA-guided NHEJ in 293T cells. (A) sets forth SEQ ID NO:19.
[0021] FIGS. 12A-12C depict HR at the endogenous AAVS1 locus using either a dsDNA donor or a short oligonucleotide donor. (C) sets forth SEQ ID NOs:37-38.
[0022] FIGS. 13A-13B depict the methodology for multiplex synthesis, retrieval and U6 expression vector cloning of guide RNAs targeting genes in the human genome. (A) sets forth SEQ ID NOs:39-41.
[0023] FIGS. 14A-14D depict CRISPR mediated RNA-guided transcriptional activation. (A) sets forth SEQ ID NOs:42-43.
[0024] FIGS. 15A-15B depict gRNA sequence flexibility and applications thereof. (A) sets forth SEQ ID NO:44.
DETAILED DESCRIPTION
[0025] According to one aspect, a human codon-optimized version of the Cas9 protein bearing a C-terminus SV40 nuclear localization signal is synthetized and cloned into a mammalian expression system ( FIG. 1A and FIG. 3A ). Accordingly, FIG. 1 is directed to genome editing in human cells using an engineered type II CRISPR system. As shown in FIG. 1A , RNA-guided gene targeting in human cells involves co-expression of the Cas9 protein bearing a C-terminus SV40 nuclear localization signal with one or more guide RNAs (gRNAs) expressed from the human U6 polymerase III promoter. Cas9 unwinds the DNA duplex and cleaves both strands upon recognition of a target sequence by the gRNA, but only if the correct protospacer-adjacent motif (PAM) is present at the 3′ end. Any genomic sequence of the form GN 20 GG can in principle be targeted. As shown in FIG. 1B , a genomically integrated GFP coding sequence is disrupted by the insertion of a stop codon and a 68 bp genomic fragment from the AAVS1 locus. Restoration of the GFP sequence by homologous recombination (HR) with an appropriate donor sequence results in GFP + cells that can be quantitated by FACS. T1 and T2 gRNAs target sequences within the AAVS1 fragment. Binding sites for the two halves of the TAL effector nuclease heterodimer (TALEN) are underlined. As shown in FIG. 1C , bar graph depict HR efficiencies induced by T1, T2, and TALEN-mediated nuclease activity at the target locus, as measured by FACS. Representative FACS plots and microscopy images of the targeted cells are depicted below (scale bar is 100 microns). Data is mean+/−SEM (N=3).
[0026] According to one aspect, to direct Cas9 to cleave sequences of interest, crRNA-tracrRNA fusion transcripts are expressed, hereafter referred to as guide RNAs (gRNAs), from the human U6 polymerase III promoter. According to one aspect, gRNAs are directly transcribed by the cell. This aspect advantageously avoids reconstituting the RNA processing machinery employed by bacterial CRISPR systems ( FIG. 1A and FIG. 3B ) (see references (4, 7-9)). According to one aspect, a method is provided for altering genomic DNA using a U6 transcription initiating with G and a PAM (protospacer-adjacent motif) sequence −NGG following the 20 bp crRNA target. According to this aspect, the target genomic site is in the form of GN 20 GG (See FIG. 3C ).
[0027] According to one aspect, a GFP reporter assay ( FIG. 1B ) in 293T cells was developed similar to one previously described (see reference (10)) to test the functionality of the genome engineering methods described herein. According to one aspect, a stable cell line was established bearing a genomically integrated GFP coding sequence disrupted by the insertion of a stop codon and a 68 bp genomic fragment from the AAVS1 locus that renders the expressed protein fragment non-fluorescent. Homologous recombination (HR) using an appropriate repair donor can restore the normal GFP sequence, which allows one to quantify the resulting GFP cells by flow activated cell sorting (FACS).
[0028] According to one aspect, a method is provided of homologous recombination (HR). Two gRNAs are constructed, T1 and T2, that target the intervening AAVS1 fragment ( FIG. 1 b ). Their activity to that of a previously described TAL effector nuclease heterodimer (TALEN) targeting the same region (see reference (11)) was compared. Successful HR events were observed using all three targeting reagents, with gene correction rates using the T1 and T2 gRNAs approaching 3% and 8% respectively ( FIG. 1C ). This RNA-mediated editing process was notably rapid, with the first detectable GFP cells appearing ˜20 hours post transfection compared to ˜40 hours for the AAVS1 TALENs. HR was observed only upon simultaneous introduction of the repair donor, Cas9 protein, and gRNA, confirming that all components are required for genome editing ( FIG. 4 ). While no apparent toxicity associated with Cas9/crRNA expression was noted, work with ZFNs and TALENs has shown that nicking only one strand further reduces toxicity. Accordingly, a Cas9D10A mutant was tested that is known to function as a nickase in vitro, which yielded similar HR but lower non-homologous end joining (NHEJ) rates ( FIG. 5 ) (see references (4, 5)). Consistent with (4) where a related Cas9 protein is shown to cut both strands 6 bp upstream of the PAM, NHEJ data confirmed that most deletions or insertions occurred at the 3′ end of the target sequence ( FIG. 5B ). Also confirmed was that mutating the target genomic site prevents the gRNA from effecting HR at that locus, demonstrating that CRISPR-mediated genome editing is sequence specific ( FIG. 6 ). It was showed that two gRNAs targeting sites in the GFP gene, and also three additional gRNAs targeting fragments from homologous regions of the DNA methyl transferase 3a (DNMT3a) and DNMT3b genes could sequence specifically induce significant HR in the engineered reporter cell lines ( FIG. 7 , 8 ). Together these results confirm that RNA-guided genome targeting in human cells induces robust HR across multiple target sites.
[0029] According to certain aspects, a native locus was modified. gRNAs were used to target the AAVS1 locus located in the PPP1R12C gene on chromosome 19, which is ubiquitously expressed across most tissues ( FIG. 2A ) in 293 Ts, K562s, and PGP1 human iPS cells (see reference (12)) and analyzed the results by next-generation sequencing of the targeted locus. Accordingly, FIG. 2 is directed to RNA-guided genome editing of the native AAVS1 locus in multiple cell types. As shown in FIG. 2A , T1 (red) and T2 (green) gRNAs target sequences in an intron of the PPP1R12C gene within the chromosome 19 AAVS1 locus. As shown in FIG. 2B , total count and location of deletions caused by NHEJ in 293 Ts, K562s, and PGP1 iPS cells following expression of Cas9 and either T1 or T2 gRNAs as quantified by next-generation sequencing is provided. Red and green dash lines demarcate the boundaries of the T1 and T2 gRNA targeting sites. NHEJ frequencies for T1 and T2 gRNAs were 10% and 25% in 293T, 13% and 38% in K562, and 2% and 4% in PGP1 iPS cells, respectively. As shown in FIG. 2C , DNA donor architecture for HR at the AAVS1 locus, and the locations of sequencing primers (arrows) for detecting successful targeted events, are depicted. As shown in FIG. 2D , PCR assay three days post transfection demonstrates that only cells expressing the donor, Cas9 and T2 gRNA exhibit successful HR events. As shown in FIG. 2E , successful HR was confirmed by Sanger sequencing of the PCR amplicon showing that the expected DNA bases at both the genome-donor and donor-insert boundaries are present. As shown in FIG. 2F , successfully targeted clones of 293T cells were selected with puromycin for 2 weeks. Microscope images of two representative GFP+ clones is shown (scale bar is 100 microns).
[0030] Consistent with results for the GFP reporter assay, high numbers of NHEJ events were observed at the endogenous locus for all three cell types. The two gRNAs T1 and T2 achieved NHEJ rates of 10 and 25% in 293 Ts, 13 and 38% in K562s, and 2 and 4% in PGP1-iPS cells, respectively ( FIG. 2B ). No overt toxicity was observed from the Cas9 and crRNA expression required to induce NHEJ in any of these cell types ( FIG. 9 ). As expected, NHEJ-mediated deletions for T1 and T2 were centered around the target site positions, further validating the sequence specificity of this targeting process ( FIG. 9 , 10 , 11 ). Simultaneous introduction of both T1 and T2 gRNAs resulted in high efficiency deletion of the intervening 19 bp fragment ( FIG. 10 ), demonstrating that multiplexed editing of genomic loci is feasible using this approach.
[0031] According to one aspect, HR is used to integrate either a dsDNA donor construct (see reference (H)) or an oligo donor into the native AAVS1 locus ( FIG. 2C , FIG. 12 ). HR-mediated integration was confirmed using both approaches by PCR ( FIG. 2D , FIG. 12 ) and Sanger sequencing ( FIG. 2E ). 293T or iPS clones were readily derived from the pool of modified cells using puromycin selection over two weeks ( FIG. 2F , FIG. 12 ). These results demonstrate that Cas9 is capable of efficiently integrating foreign DNA at endogenous loci in human cells. Accordingly, one aspect of the present disclosure includes a method of integrating foreign DNA into the genome of a cell using homologous recombination and Cas9.
[0032] According to one aspect, an RNA-guided genome editing system is provided which can readily be adapted to modify other genomic sites by simply modifying the sequence of the gRNA expression vector to match a compatible sequence in the locus of interest. According to this aspect, 190,000 specifically gRNA-targetable sequences targeting about 40.5% exons of genes in the human genome were generated. These target sequences were incorporated into a 200 bp format compatible with multiplex synthesis on DNA arrays (see reference (14)) ( FIG. 13 ). According to this aspect, a ready genome-wide reference of potential target sites in the human genome and a methodology for multiplex gRNA synthesis is provided.
[0033] According to one aspect, methods are provided for multiplexing genomic alterations in a cell by using one or more or a plurality of RNA/enzyme systems described herein to alter the genome of a cell at a plurality of locations. According to one aspect, target sites perfectly match the PAM sequence NGG and the 8-12 base “seed sequence” at the 3′ end of the gRNA. According to certain aspects, perfect match is not required of the remaining 8-12 bases. According to certain aspects, Cas9 will function with single mismatches at the 5′ end. According to certain aspects, the target locus's underlying chromatin structure and epigenetic state may affect efficiency of Cas9 function. According to certain aspects, Cas9 homologs having higher specificity are included as useful enzymes. One of skill in the art will be able to identify or engineer suitable Cas9 homologs. According to one aspect, CRISPR-targetable sequences include those having different PAM requirements (see reference (9)), or directed evolution. According to one aspect, inactivating one of the Cas9 nuclease domains increases the ratio of HR to NHEJ and may reduce toxicity ( FIG. 3A , FIG. 5 ) (4, 5), while inactivating both domains may enable Cas9 to function as a retargetable DNA binding protein. Embodiments of the present disclosure have broad utility in synthetic biology (see references (21, 22)), the direct and multiplexed perturbation of gene networks (see references (13, 23)), and targeted ex vivo (see references (24-26)) and in vivo gene therapy (see reference (27)).
[0034] According to certain aspects, a “re-engineerable organism” is provided as a model system for biological discovery and in vivo screening. According to one aspect, a “re-engineerable mouse” bearing an inducible Cas9 transgene is provided, and localized delivery (using adeno-associated viruses, for example) of libraries of gRNAs targeting multiple genes or regulatory elements allow one to screen for mutations that result in the onset of tumors in the target tissue type. Use of Cas9 homologs or nuclease-null variants bearing effector domains (such as activators) allow one to multiplex activate or repress genes in vivo. According to this aspect, one could screen for factors that enable phenotypes such as: tissue-regeneration, trans-differentiation etc. According to certain aspects, (a) use of DNA-arrays enables multiplex synthesis of defined gRNA libraries (refer FIG. 13 ); and (b) gRNAs being small in size (refer FIG. 3 b ) are packaged and delivered using a multitude of non-viral or viral delivery methods.
[0035] According to one aspect, the lower toxicities observed with “nickases” for genome engineering applications is achieved by inactivating one of the Cas9 nuclease domains, either the nicking of the DNA strand base-paired with the RNA or nicking its complement. Inactivating both domains allows Cas9 to function as a retargetable DNA binding protein. According to one aspect, the Cas9 retargetable DNA binding protein is attached
[0000] (a) to transcriptional activation or repression domains for modulating target gene expression, including but not limited to chromatin remodeling, histone modification, silencing, insulation, direct interactions with the transcriptional machinery;
(b) to nuclease domains such as FokI to enable ‘highly specific’ genome editing contingent upon dimerization of adjacent gRNA-Cas9 complexes;
(c) to fluorescent proteins for visualizing genomic loci and chromosome dynamics; or
(d) to other fluorescent molecules such as protein or nucleic acid bound organic fluorophores, quantum dots, molecular beacons and echo probes or molecular beacon replacements;
(e) to multivalent ligand-binding protein domains that enable programmable manipulation of genome-wide 3D architecture.
[0036] According to one aspect, the transcriptional activation and repression components can employ CRISPR systems naturally or synthetically orthogonal, such that the gRNAs only bind to the activator or repressor class of Cas. This allows a large set of gRNAs to tune multiple targets.
[0037] According to certain aspects, the use of gRNAs provide the ability to multiplex than mRNAs in part due to the smaller size—100 vs. 2000 nucleotide lengths respectively. This is particularly valuable when nucleic acid delivery is size limited, as in viral packaging. This enables multiple instances of cleavage, nicking, activation, or repression—or combinations thereof. The ability to easily target multiple regulatory targets allows the coarse-or-fine-tuning or regulatory networks without being constrained to the natural regulatory circuits downstream of specific regulatory factors (e.g. the 4 mRNAs used in reprogramming fibroblasts into IPSCs). Examples of multiplexing applications include:
[0000] 1. Establishing (major and minor) histocompatibility alleles, haplotypes, and genotypes for human (or animal) tissue/organ transplantation. This aspect results e.g. in HLA homozygous cell lines or humanized animal breeds—or—a set of gRNAs capable of superimposing such HLA alleles onto an otherwise desirable cell lines or breeds.
2. Multiplex cis-regulatory element (CRE=signals for transcription, splicing, translation, RNA and protein folding, degradation, etc.) mutations in a single cell (or a collection of cells) can be used for efficiently studying the complex sets of regulatory interaction that can occur in normal development or pathological, synthetic or pharmaceutical scenarios. According to one aspect, the CREs are (or can be made) somewhat orthogonal (i.e. low cross talk) so that many can be tested in one setting—e.g. in an expensive animal embryo time series. One exemplary application is with RNA fluorescent in situ sequencing (FISSeq).
3. Multiplex combinations of CRE mutations and/or epigenetic activation or repression of CREs can be used to alter or reprogram iPSCs or ESCs or other stem cells or non-stem cells to any cell type or combination of cell types for use in organs-on-chips or other cell and organ cultures for purposes of testing pharmaceuticals (small molecules, proteins, RNAs, cells, animal, plant or microbial cells, aerosols and other delivery methods), transplantation strategies, personalization strategies, etc.
4. Making multiplex mutant human cells for use in diagnostic testing (and/or DNA sequencing) for medical genetics. To the extent that the chromosomal location and context of a human genome allele (or epigenetic mark) can influence the accuracy of a clinical genetic diagnosis, it is important to have alleles present in the correct location in a reference genome—rather than in an ectopic (aka transgenic) location or in a separate piece of synthetic DNA. One embodiment is a series of independent cell lines one per each diagnostic human SNP, or structural variant. Alternatively, one embodiment includes multiplex sets of alleles in the same cell. In some cases multiplex changes in one gene (or multiple genes) will be desirable under the assumption of independent testing. In other cases, particular haplotype combinations of alleles allows testing of sequencing (genotyping) methods which accurately establish haplotype phase (i.e. whether one or both copies of a gene are affected in an individual person or somatic cell type.
5. Repetitive elements or endogenous viral elements can be targeted with engineered Cas+gRNA systems in microbes, plants, animals, or human cells to reduce deleterious transposition or to aid in sequencing or other analytic genomic/transcriptomic/proteomic/diagnostic tools (in which nearly identical copies can be problematic).
[0038] The following references identified by number in the foregoing section are hereby incorporated by reference in their entireties.
1. B. Wiedenheft, S. H. Sternberg, J. A. Doudna, Nature 482, 331 (Feb. 16, 2012). 2. D. Bhaya, M. Davison, R. Barrangou, Annual review of genetics 45, 273 (2011). 3. M. P. Terns, R. M. Terns, Current opinion in microbiology 14, 321 (June, 2011). 4. M. Jinek et al., Science 337, 816 (Aug. 17, 2012). 5. G. Gasiunas, R. Barrangou, P. Horvath, V. Siksnys, Proceedings of the National Academy of Sciences of the United States of America 109, E2579 (Sep. 25, 2012). 6. R. Sapranauskas et al., Nucleic acids research 39, 9275 (November, 2011). 7. T. R. Brummelkamp, R. Bernards, R. Agami, Science 296, 550 (Apr. 19, 2002). 8. M. Miyagishi, K. Taira, Nature biotechnology 20, 497 (May, 2002). 9. E. Deltcheva et al., Nature 471, 602 (Mar. 31, 2011). 10. J. Zou, P. Mali, X. Huang, S. N. Dowey, L. Cheng, Blood 118, 4599 (Oct. 27, 2011). 11. N. E. Sanjana et al., Nature protocols 7, 171 (January, 2012). 12. J. H. Lee et al., PLoS Genet 5, e1000718 (November, 2009). 13. D. Hockemeyer et al., Nature biotechnology 27, 851 (September, 2009). 14. S. Kosuri et al., Nature biotechnology 28, 1295 (December, 2010). 15. V. Pattanayak, C. L. Ramirez, J. K. Joung, D. R. Liu, Nature methods 8, 765 (September, 2011). 16. N. M. King, O. Cohen-Haguenauer, Molecular therapy: the journal of the American Society of Gene Therapy 16, 432 (March, 2008). 17. Y. G. Kim, J. Cha, S. Chandrasegaran, Proceedings of the National Academy of Sciences of the United States of America 93, 1156 (Feb. 6, 1996). 18. E. J. Rebar, C. O. Pabo, Science 263, 671 (Feb. 4, 1994). 19. J. Boch et al., Science 326, 1509 (Dec. 11, 2009). 20. M. J. Moscou, A. J. Bogdanove, Science 326, 1501 (Dec. 11, 2009). 21. A. S. Khalil, J. J. Collins, Nature reviews. Genetics 11, 367 (May, 2010). 22. P. E. Purnick, R. Weiss, Nature reviews. Molecular cell biology 10, 410 (June, 2009). 23. J. Zou et al., Cell stem cell 5, 97 (Jul. 2, 2009). 24. N. Holt et al., Nature biotechnology 28, 839 (August, 2010). 25. F. D. Urnov et al., Nature 435, 646 (Jun. 2, 2005). 26. A. Lombardo et al., Nature biotechnology 25, 1298 (November, 2007). 27. H. Li et al., Nature 475, 217 (Jul. 14, 2011).
[0066] The following examples are set forth as being representative of the present disclosure. These examples are not to be construed as limiting the scope of the present disclosure as these and other equivalent embodiments will be apparent in view of the present disclosure, figures and accompanying claims.
Example I
The Type II CRISPR-Cas System
[0067] According to one aspect, embodiments of the present disclosure utilize short RNA to identify foreign nucleic acids for activity by a nuclease in a eukaryotic cell. According to a certain aspect of the present disclosure, a eukaryotic cell is altered to include within its genome nucleic acids encoding one or more short RNA and one or more nucleases which are activated by the binding of a short RNA to a target DNA sequence. According to certain aspects, exemplary short RNA/enzyme systems may be identified within bacteria or archaea, such as (CRISPR)/CRISPR-associated (Cas) systems that use short RNA to direct degradation of foreign nucleic acids. CRISPR (“clustered regularly interspaced short palindromic repeats”) defense involves acquisition and integration of new targeting “spacers” from invading virus or plasmid DNA into the CRISPR locus, expression and processing of short guiding CRISPR RNAs (crRNAs) consisting of spacer-repeat units, and cleavage of nucleic acids (most commonly DNA) complementary to the spacer.
[0068] Three classes of CRISPR systems are generally known and are referred to as Type I, Type II or Type III). According to one aspect, a particular useful enzyme according to the present disclosure to cleave dsDNA is the single effector enzyme, Cas9, common to Type II. (See reference (1)). Within bacteria, the Type II effector system consists of a long pre-crRNA transcribed from the spacer-containing CRISPR locus, the multifunctional Cas9 protein, and a tracrRNA important for gRNA processing. The tracrRNAs hybridize to the repeat regions separating the spacers of the pre-crRNA, initiating dsRNA cleavage by endogenous RNase III, which is followed by a second cleavage event within each spacer by Cas9, producing mature crRNAs that remain associated with the tracrRNA and Cas9. According to one aspect, eukaryotic cells of the present disclosure are engineered to avoid use of RNase III and the crRNA processing in general. See reference (2).
[0069] According to one aspect, the enzyme of the present disclosure, such as Cas9 unwinds the DNA duplex and searches for sequences matching the crRNA to cleave. Target recognition occurs upon detection of complementarity between a “protospacer” sequence in the target DNA and the remaining spacer sequence in the crRNA. Importantly, Cas9 cuts the DNA only if a correct protospacer-adjacent motif (PAM) is also present at the 3′ end. According to certain aspects, different protospacer-adjacent motif can be utilized. For example, the S. pyogenes system requires an NGG sequence, where N can be any nucleotide. S. thermophilus Type II systems require NGGNG (see reference (3)) and NNAGAAW (see reference (4)), respectively, while different S. mutans systems tolerate NGG or NAAR (see reference (5)). Bioinformatic analyses have generated extensive databases of CRISPR loci in a variety of bacteria that may serve to identify additional useful PAMs and expand the set of CRISPR-targetable sequences (see references (6, 7)). In S. thermophilus , Cas9 generates a blunt-ended double-stranded break 3 bp prior to the 3′ end of the protospacer (see reference (8)), a process mediated by two catalytic domains in the Cas9 protein: an HNH domain that cleaves the complementary strand of the DNA and a RuvC-like domain that cleaves the non-complementary strand (See FIG. 1A and FIG. 3 ). While the S. pyogenes system has not been characterized to the same level of precision, DSB formation also occurs towards the 3′ end of the protospacer. If one of the two nuclease domains is inactivated, Cas9 will function as a nickase in vitro (see reference (2)) and in human cells (see FIG. 5 ).
[0070] According to one aspect, the specificity of gRNA-directed Cas9 cleavage is used as a mechanism for genome engineering in a eukaryotic cell. According to one aspect, hybridization of the gRNA need not be 100 percent in order for the enzyme to recognize the gRNA/DNA hybrid and affect cleavage. Some off-target activity could occur. For example, the S. pyogenes system tolerates mismatches in the first 6 bases out of the 20 bp mature spacer sequence in vitro. According to one aspect, greater stringency may be beneficial in vivo when potential off-target sites matching (last 14 bp) NGG exist within the human reference genome for the gRNAs. The effect of mismatches and enzyme activity in general are described in references (9), (2), (10), and (4).
[0071] According to certain aspects, specificity may be improved. When interference is sensitive to the melting temperature of the gRNA-DNA hybrid, AT-rich target sequences may have fewer off-target sites. Carefully choosing target sites to avoid pseudo-sites with at least 14 bp matching sequences elsewhere in the genome may improve specificity. The use of a Cas9 variant requiring a longer PAM sequence may reduce the frequency of off-target sites. Directed evolution may improve Cas9 specificity to a level sufficient to completely preclude off-target activity, ideally requiring a perfect 20 bp gRNA match with a minimal PAM. Accordingly, modification to the Cas9 protein is a representative embodiment of the present disclosure. As such, novel methods permitting many rounds of evolution in a short timeframe (see reference (11) and envisioned. CRISPR systems useful in the present disclosure are described in references (12, 13).
Example II
Plasmid Construction
[0072] The Cas9 gene sequence was human codon optimized and assembled by hierarchical fusion PCR assembly of 9 500 bp gBlocks ordered from IDT. FIG. 3A for the engineered type II CRISPR system for human cells shows the expression format and full sequence of the cas9 gene insert. The RuvC-like and HNH motifs, and the C-terminus SV40 NLS are respectively highlighted by blue, brown and orange colors. Cas9_D10A was similarly constructed. The resulting full-length products were cloned into the pcDNA3.3-TOPO vector (Invitrogen). The target gRNA expression constructs were directly ordered as individual 455 bp gBlocks from IDT and either cloned into the pCR-BluntII-TOPO vector (Invitrogen) or per amplified. FIG. 3B shows the U6 promoter based expression scheme for the guide RNAs and predicted RNA transcript secondary structure. The use of the U6 promoter constrains the 1 st position in the RNA transcript to be a ‘G’ and thus all genomic sites of the form GN 20 GG can be targeted using this approach. FIG. 3C shows the 7 gRNAs used.
[0073] The vectors for the HR reporter assay involving a broken GFP were constructed by fusion PCR assembly of the GFP sequence bearing the stop codon and 68 bp AAVS1 fragment (or mutants thereof see FIG. 6 ), or 58 bp fragments from the DNMT3a and DNMT3b genomic loci (see FIG. 8 ) assembled into the EGIP lentivector from Addgene (plasmid #26777). These lentivectors were then used to establish the GFP reporter stable lines. TALENs used in this study were constructed using the protocols described in (14). All DNA reagents developed in this study are available at Addgene.
Example III
Cell Culture
[0074] PGP1 iPS cells were maintained on Matrigel (BD Biosciences)-coated plates in mTeSR1 (Stemcell Technologies). Cultures were passaged every 5-7 d with TrypLE Express (Invitrogen). K562 cells were grown and maintained in RPMI (Invitrogen) containing 15% FBS. HEK 293T cells were cultured in Dulbecco's modified Eagle's medium (DMEM, Invitrogen) high glucose supplemented with 10% fetal bovine serum (FBS, Invitrogen), penicillin/streptomycin (pen/strep, Invitrogen), and non-essential amino acids (NEAA, Invitrogen). All cells were maintained at 37° C. and 5% CO 2 in a humidified incubator.
Example IV
Gene Targeting of PGP1 iPS, K562 and 293 Ts
[0075] PGP1 iPS cells were cultured in Rho kinase (ROCK) inhibitor (Calbiochem) 2 h before nucleofection. Cells were harvest using TrypLE Express (Invitrogen) and 2×10 6 cells were resuspended in P3 reagent (Lonza) with 1 μg Cas9 plasmid, 1 μg gRNA and/or 1 μg DNA donor plasmid, and nucleofected according to manufacturer's instruction (Lonza). Cells were subsequently plated on an mTeSR1-coated plate in mTeSR1 medium supplemented with ROCK inhibitor for the first 24 h. For K562s, 2×10 6 cells were resuspended in SF reagent (Lonza) with 1 μg Cas9 plasmid, 1 μg gRNA and/or 1 μg DNA donor plasmid, and nucleofected according to manufacturer's instruction (Lonza). For 293 Ts, 0.1×10 6 cells were transfected with 1 μg Cas9 plasmid, 1 μg gRNA and/or 1 μg DNA donor plasmid using Lipofectamine 2000 as per the manufacturer's protocols. The DNA donors used for endogenous AAVS1 targeting were either a dsDNA donor ( FIG. 2C ) or a 90mer oligonucleotide. The former has flanking short homology arms and a SA-2A-puromycin-CaGGS-eGFP cassette to enrich for successfully targeted cells.
[0076] The targeting efficiency was assessed as follows. Cells were harvested 3 days after nucleofection and the genomic DNA of ˜1×10 6 cells was extracted using prepGEM (ZyGEM). PCR was conducted to amplify the targeting region with genomic DNA derived from the cells and amplicons were deep sequenced by MiSeq Personal Sequencer (Illumina) with coverage >200,000 reads. The sequencing data was analyzed to estimate NHEJ efficiencies. The reference AAVS 1 sequence analyzed is:
[0000] (SEQ ID NO: 1) CACTTCAGGACAGCATGTTTGCTGCCTCCAGGGATCCTGTGTCCCCGAGCTGGGACCACCTT ATATTCCCAGGGCCGGTTAATGTGGCTCTGGTTCTGGGTACTTTTATCTGTCCCCTCCACCCC ACAGTGGGGCCACTAGGGACAGGATTGGTGACAGAAAAGCCCCATCCTTAGGCCTCCTCCTT CCTAGTCTCCTGATATTGGGTCTAACCCCCACCTCCTGTTAGGCAGATTCCTTATCTGGTGAC ACACCCCCATTTCCTGGA
The PCR primers for amplifying the targeting regions in the human genome are:
[0000]
(SEQ ID NO: 2)
AAVS1-R
CTCGGCATTCCTGCTGAACCGCTCTTCCGATCTacaggaggtgggggttagac
(SEQ ID NO: 3)
AAVS1-F.1
ACACTCTTTCCCTACACGACGCTCTTCCGATCTCGTGATtatattcccagggccggtta
(SEQ ID NO: 4)
AAVS1-F.2
ACACTCTTTCCCTACACGACGCTCTTCCGATCTACATCGtatattcccagggccggtta
(SEQ ID NO: 5)
AAVS1-F.3
ACACTCTTTCCCTACACGACGCTCTTCCGATCTGCCTAAtatattcccagggccggtta
(SEQ ID NO: 6)
AAVS1-F.4
ACACTCTTTCCCTACACGACGCTCTTCCGATCTTGGTCAtatattcccagggccggtta
(SEQ ID NO: 7)
AAVS1-F.5
ACACTCTTTCCCTACACGACGCTCTTCCGATCTCACTGTtatattcccagggccggtta
(SEQ ID NO: 8)
AAVS1-F.6
ACACTCTTTCCCTACACGACGCTCTTCCGATCTATTGGCtatattcccagggccggtta
(SEQ ID NO: 9)
AAVS1-F.7
ACACTCTTTCCCTACACGACGCTCTTCCGATCTGATCTGtatattcccagggccggtta
(SEQ ID NO: 10)
AAVS1-F.8
ACACTCTTTCCCTACACGACGCTCTTCCGATCTTCAAGTtatattcccagggccggtta
(SEQ ID NO: 11)
AAVS1-F.9
ACACTCTTTCCCTACACGACGCTCTTCCGATCTCTGATCtatattcccagggccggtta
(SEQ ID NO: 12)
AAVS1-F.10
ACACTCTTTCCCTACACGACGCTCTTCCGATCTAAGCTAtatattcccagggccggtta
(SEQ ID NO: 13)
AAVS1-F.11
ACACTCTTTCCCTACACGACGCTCTTCCGATCTGTAGCCtatattcccagggccggtta
(SEQ ID NO: 14)
AAVS1-F.12
ACACTCTTTCCCTACACGACGCTCTTCCGATCTTACAAGtatattcccagggccggtta
[0077] To analyze the HR events using the DNA donor in FIG. 2C , the primers used were:
[0000]
(SEQ ID NO: 15)
HR_AAVS1-F
CTGCCGTCTCTCTCCTGAGT
(SEQ ID NO: 16)
HR_Puro-R
GTGGGCTTGTACTCGGTCAT
Example V
Bioinformatics Approach for Computing Human Exon CRISPR Targets and Methodology for their Multiplexed Synthesis
[0078] A set of gRNA gene sequences that maximally target specific locations in human exons but minimally target other locations in the genome were determined as follows. According to one aspect, maximally efficient targeting by a gRNA is achieved by 23 nt sequences, the 5′-most 20 nt of which exactly complement a desired location, while the three 3′-most bases must be of the form NGG. Additionally, the 5′-most nt must be a G to establish a pol-III transcription start site. However, according to (2), mispairing of the six 5′-most nt of a 20 bp gRNA against its genomic target does not abrogate Cas9-mediated cleavage so long as the last 14 nt pairs properly, but mispairing of the eight 5′-most nt along with pairing of the last 12 nt does, while the case of the seven 5-most nt mispairs and 13 3′ pairs was not tested. To be conservative regarding off-target effects, one condition was that the case of the seven 5′-most mispairs is, like the case of six, permissive of cleavage, so that pairing of the 3′-most 13 nt is sufficient for cleavage. To identify CRISPR target sites within human exons that should be cleavable without off-target cuts, all 23 bp sequences of the form 5′-GBBBB BBBBB BBBBB BBBBB NGG-3′ (form 1) were examined, where the B's represent the bases at the exon location, for which no sequence of the form 5′-NNNNN NNBBB BBBBB BBBBB NGG-3′ (form 2) existed at any other location in the human genome. Specifically, (i) a BED file of locations of coding regions of all RefSeq genes the GRCh37/hg19 human genome from the UCSC Genome Browser (15-17) was downloaded. Coding exon locations in this BED file comprised a set of 346089 mappings of RefSeq mRNA accessions to the hg19 genome. However, some RefSeq mRNA accessions mapped to multiple genomic locations (probable gene duplications), and many accessions mapped to subsets of the same set of exon locations (multiple isoforms of the same genes). To distinguish apparently duplicated gene instances and consolidate multiple references to the same genomic exon instance by multiple RefSeq isoform accessions, (ii) unique numerical suffixes to 705 RefSeq accession numbers that had multiple genomic locations were added, and (iii) the mergeBed function of BEDTools (18) (v2.16.2-zip-87e3926) was used to consolidate overlapping exon locations into merged exon regions. These steps reduced the initial set of 346089 RefSeq exon locations to 192783 distinct genomic regions. The hg19 sequence for all merged exon regions were downloaded using the UCSC Table Browser, adding 20 bp of padding on each end. (iv) Using custom perl code, 1657793 instances of form 1 were identified within this exonic sequence. (v) These sequences were then filtered for the existence of off-target occurrences of form 2: For each merged exon form 1 target, the 3′-most 13 bp specific (B) “core” sequences were extracted and, for each core generated the four 16 bp sequences 5′-BBB BBBBB BBBBB NGG-3′ (N=A, C, G, and T), and searched the entire hg19 genome for exact matches to these 6631172 sequences using Bowtie version 0.12.8 (19) using the parameters −l 16 −v 0 −k 2. Any exon target site for which there was more than a single match was rejected. Note that because any specific 13 bp core sequence followed by the sequence NGG confers only 15 bp of specificity, there should be on average ˜5.6 matches to an extended core sequence in a random ˜3 Gb sequence (both strands). Therefore, most of the 1657793 initially identified targets were rejected; however 189864 sequences passed this filter. These comprise the set of CRISPR-targetable exonic locations in the human genome. The 189864 sequences target locations in 78028 merged exonic regions (˜40.5% of the total of 192783 merged human exon regions) at a multiplicity of ˜2.4 sites per targeted exonic region. To assess targeting at a gene level, RefSeq mRNA mappings were clustered so that any two RefSeq accessions (including the gene duplicates distinguished in (ii)) that overlap a merged exon region are counted as a single gene cluster, the 189864 exonic specific CRISPR sites target 17104 out of 18872 gene clusters (˜90.6% of all gene clusters) at a multiplicity of ˜11.1 per targeted gene cluster. (Note that while these gene clusters collapse RefSeq mRNA accessions that represent multiple isoforms of a single transcribed gene into a single entity, they will also collapse overlapping distinct genes as well as genes with antisense transcripts.) At the level of original RefSeq accessions, the 189864 sequences targeted exonic regions in 30563 out of a total of 43726 (˜69.9%) mapped RefSeq accessions (including distinguished gene duplicates) at a multiplicity of ˜6.2 sites per targeted mapped RefSeq accession.
[0079] According to one aspect, the database can be refined by correlating performance with factors, such as base composition and secondary structure of both gRNAs and genomic targets (20, 21), and the epigenetic state of these targets in human cell lines for which this information is available (22).
Example VI
Multiplex Synthesis
[0080] The target sequences were incorporated into a 200 bp format that is compatible for multiplex synthesis on DNA arrays (23, 24). According to one aspect the method allows for targeted retrieval of a specific or pools of gRNA sequences from the DNA array based oligonucleotide pool and its rapid cloning into a common expression vector ( FIG. 13A ). Specifically, a 12 k oligonucleotide pool from CustomArray Inc. was synthesized. Furthermore, gRNAs of choice from this library ( FIG. 13B ) were successfully retrieved. We observed an error rate of ˜4 mutations per 1000 bp of synthesized DNA.
Example VII
RNA-Guided Genome Editing Requires Both Cas9 and Guide RNA for Successful Targeting
[0081] Using the GFP reporter assay described in FIG. 1B , all possible combinations of the repair DNA donor, Cas9 protein, and gRNA were tested for their ability to effect successful HR (in 293 Ts). As shown in FIG. 4 , GFP+ cells were observed only when all the 3 components were present, validating that these CRISPR components are essential for RNA-guided genome editing. Data is mean+/−SEM (N=3).
Example VIII
Analysis of gRNA and Cas9 Mediated Genome Editing
[0082] The CRISPR mediated genome editing process was examined using either (A) a GFP reporter assay as described earlier results of which are shown in FIG. 5A , and (B) deep sequencing of the targeted loci (in 293 Ts), results of which are shown in FIG. 5B . As comparison, a D10A mutant for Cas9 was tested that has been shown in earlier reports to function as a nickase in in vitro assays. As shown in FIG. 5 , both Cas9 and Cas9D10A can effect successful HR at nearly similar rates. Deep sequencing however confirms that while Cas9 shows robust NHEJ at the targeted loci, the D10A mutant has significantly diminished NHEJ rates (as would be expected from its putative ability to only nick DNA). Also, consistent with the known biochemistry of the Cas9 protein, NHEJ data confirms that most base-pair deletions or insertions occurred near the 3′ end of the target sequence: the peak is ˜3-4 bases upstream of the PAM site, with a median deletion frequency of ˜9-10 bp. Data is mean+/−SEM (N=3).
Example IX
RNA-Guided Genome Editing is Target Sequence Specific
[0083] Similar to the GFP reporter assay described in FIG. 1B , 3 293T stable lines each bearing a distinct GFP reporter construct were developed. These are distinguished by the sequence of the AAVS1 fragment insert (as indicated in the FIG. 6 ). One line harbored the wild-type fragment while the two other lines were mutated at 6 bp (highlighted in red). Each of the lines was then targeted by one of the following 4 reagents: a GFP-ZFN pair that can target all cell types since its targeted sequence was in the flanking GFP fragments and hence present in along cell lines; a AAVS1 TALEN that could potentially target only the wt-AAVS1 fragment since the mutations in the other two lines should render the left TALEN unable to bind their sites; the T1 gRNA which can also potentially target only the wt-AAVS1 fragment, since its target site is also disrupted in the two mutant lines; and finally the T2 gRNA which should be able to target all 3 cell lines since, unlike the T1 gRNA, its target site is unaltered among the 3 lines. ZFN modified all 3 cell types, the AAVS1 TALENs and the T1 gRNA only targeted the wt-AAVS1 cell type, and the T2 gRNA successfully targets all 3 cell types. These results together confirm that the guide RNA mediated editing is target sequence specific. Data is mean+/−SEM (N=3).
Example X
Guide RNAs Targeted to the GFP Sequence Enable Robust Genome Editing
[0084] In addition to the 2 gRNAs targeting the AAVS1 insert, two additional gRNAs targeting the flanking GFP sequences of the reporter described in FIG. 1B (in 293 Ts) were tested. As shown in FIG. 7 , these gRNAs were also able to effect robust HR at this engineered locus. Data is mean+/−SEM (N=3).
Example XI
RNA-Guided Genome Editing is Target Sequence Specific, and Demonstrates Similar Targeting Efficiencies as ZFNs or TALENs
[0085] Similar to the GFP reporter assay described in FIG. 1B , two 293T stable lines each bearing a distinct GFP reporter construct were developed. These are distinguished by the sequence of the fragment insert (as indicated in FIG. 8 ). One line harbored a 58 bp fragment from the DNMT3a gene while the other line bore a homologous 58 bp fragment from the DNMT3b gene. The sequence differences are highlighted in red. Each of the lines was then targeted by one of the following 6 reagents: a GFP-ZFN pair that can target all cell types since its targeted sequence was in the flanking GFP fragments and hence present in along cell lines; a pair of TALENs that potentially target either DNMT3a or DNMT3b fragments; a pair of gRNAs that can potentially target only the DNMT3a fragment; and finally a gRNA that should potentially only target the DNMT3b fragment. As indicated in FIG. 8 , the ZFN modified all 3 cell types, and the TALENs and gRNAs only their respective targets. Furthermore the efficiencies of targeting were comparable across the 6 targeting reagents. These results together confirm that RNA-guided editing is target sequence specific and demonstrates similar targeting efficiencies as ZFNs or TALENs. Data is mean+/−SEM (N=3).
Example XII
RNA-Guided NHEJ in Human iPS Cells
[0086] Human iPS cells (PGP1) were nucleofected with constructs indicated in the left panel of FIG. 9 . 4 days after nucleofection, NHEJ rate was measured by assessing genomic deletion and insertion rate at double-strand breaks (DSBs) by deep sequencing. Panel 1: Deletion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The deletion incidence at each nucleotide position was plotted in black lines and the deletion rate as the percentage of reads carrying deletions was calculated. Panel 2: Insertion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The incidence of insertion at the genomic location where the first insertion junction was detected was plotted in black lines and the insertion rate as the percentage of reads carrying insertions was calculated. Panel 3: Deletion size distribution. The frequencies of different size deletions among the whole NHEJ population was plotted. Panel 4: insertion size distribution. The frequencies of different sizes insertions among the whole NHEJ population was plotted. iPS targeting by both gRNAs is efficient (2-4%), sequence specific (as shown by the shift in position of the NHEJ deletion distributions), and reaffirming the results of FIG. 4 , the NGS-based analysis also shows that both the Cas9 protein and the gRNA are essential for NHEJ events at the target locus.
Example XIII
RNA-Guided NHEJ in K562 Cells
[0087] K562 cells were nucleated with constructs indicated in the left panel of FIG. 10 . 4 days after nucleofection, NHEJ rate was measured by assessing genomic deletion and insertion rate at DSBs by deep sequencing. Panel 1: Deletion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The deletion incidence at each nucleotide position was plotted in black lines and the deletion rate as the percentage of reads carrying deletions was calculated. Panel 2: Insertion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The incidence of insertion at the genomic location where the first insertion junction was detected was plotted in black lines and the insertion rate as the percentage of reads carrying insertions was calculated. Panel 3: Deletion size distribution. The frequencies of different size deletions among the whole NHEJ population was plotted. Panel 4: insertion size distribution. The frequencies of different sizes insertions among the whole NHEJ population was plotted. K562 targeting by both gRNAs is efficient (13-38%) and sequence specific (as shown by the shift in position of the NHEJ deletion distributions). Importantly, as evidenced by the peaks in the histogram of observed frequencies of deletion sizes, simultaneous introduction of both T1 and T2 guide RNAs resulted in high efficiency deletion of the intervening 19 bp fragment, demonstrating that multiplexed editing of genomic loci is also feasible using this approach.
Example XIV
RNA-Guided NHEJ in 293T Cells
[0088] 293T cells were transfected with constructs indicated in the left panel of FIG. 11 . 4 days after nucleofection, NHEJ rate was measured by assessing genomic deletion and insertion rate at DSBs by deep sequencing. Panel 1: Deletion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The deletion incidence at each nucleotide position was plotted in black lines and the deletion rate as the percentage of reads carrying deletions was calculated. Panel 2: Insertion rate detected at targeting region. Red dash lines: boundary of T1 RNA targeting site; green dash lines: boundary of T2 RNA targeting site. The incidence of insertion at the genomic location where the first insertion junction was detected was plotted in black lines and the insertion rate as the percentage of reads carrying insertions was calculated. Panel 3: Deletion size distribution. The frequencies of different size deletions among the whole NHEJ population was plotted. Panel 4: insertion size distribution. The frequencies of different sizes insertions among the whole NHEJ population was plotted. 293T targeting by both gRNAs is efficient (10-24%) and sequence specific (as shown by the shift in position of the NHEJ deletion distributions).
Example XV
HR at the Endogenous AAVS1 Locus Using Either a dsDNA Donor or a Short Oligonucleotide Donor
[0089] As shown in FIG. 12A , PCR screen (with reference to FIG. 2C ) confirmed that 21/24 randomly picked 293T clones were successfully targeted. As shown in FIG. 12B , similar PCR screen confirmed 3/7 randomly picked PGP1-iPS clones were also successfully targeted. As shown in FIG. 12C , short 90mer oligos could also effect robust targeting at the endogenous AAVS1 locus (shown here for K562 cells).
Example XVI
Methodology for Multiplex Synthesis, Retrieval and U6 Expression Vector Cloning of Guide RNAs Targeting Genes in the Human Genome
[0090] A resource of about 190 k bioinformatically computed unique gRNA sites targeting ˜40.5% of all exons of genes in the human genome was generated. As shown in FIG. 13A , the gRNA target sites were incorporated into a 200 bp format that is compatible for multiplex synthesis on DNA arrays. Specifically, the design allows for (i) targeted retrieval of a specific or pools of gRNA targets from the DNA array oligonucleotide pool (through 3 sequential rounds of nested PCR as indicated in the figure schematic); and (ii) rapid cloning into a common expression vector which upon linearization using an AflII site serves as a recipient for Gibson assembly mediated incorporation of the gRNA insert fragment. As shown in FIG. 13B , the method was used to accomplish targeted retrieval of 10 unique gRNAs from a 12 k oligonucleotide pool synthesized by CustomArray Inc.
Example XVII
CRISPR Mediated RNA-Guided Transcriptional Activation
[0091] The CRISPR-Cas system has an adaptive immune defense system in bacteria and functions to ‘cleave’ invading nucleic acids. According to one aspect, the CRISPR-CAS system is engineered to function in human cells, and to ‘cleave’ genomic DNA. This is achieved by a short guide RNA directing a Cas9 protein (which has nuclease function) to a target sequence complementary to the spacer in the guide RNA. The ability to ‘cleave’ DNA enables a host of applications related to genome editing, and also targeted genome regulation. Towards this, the Cas9 protein was mutated to make it nuclease-null by introducing mutations that are predicted to abrogate coupling to Mg2+(known to be important for the nuclease functions of the RuvC-like and HNH-like domains): specifically, combinations of D10A, D839A, H840A and N863A mutations were introduced. The thus generated Cas9 nuclease-null protein (as confirmed by its ability to not cut DNA by sequencing analysis) and hereafter referred to as Cas9R-H-, was then coupled to a transcriptional activation domain, here VP64, enabling the CRISPR-cas system to function as a RNA guided transcription factor (see FIG. 14 ). The Cas9R-H-+VP64 fusion enables RNA-guided transcriptional activation at the two reporters shown. Specifically, both FACS analysis and immunofluorescence imaging demonstrates that the protein enables gRNA sequence specific targeting of the corresponding reporters, and furthermore, the resulting transcription activation as assayed by expression of a dTomato fluorescent protein was at levels similar to those induced by a convention TALE-VP64 fusion protein.
Example XVIII
gRNA Sequence Flexibility and Applications Thereof
[0092] Flexibility of the gRNA scaffold sequence to designer sequence insertions was determined by systematically assaying for a range of the random sequence insertions on the 5′, middle and 3′ portions of the gRNA: specifically, 1 bp, 5 bp, 10 bp, 20 bp, and 40 bp inserts were made in the gRNA sequence at the 5′, middle, and 3′ ends of the gRNA (the exact positions of the insertion are highlighted in ‘red’ in FIG. 15 ). This gRNA was then tested for functionality by its ability to induce HR in a GFP reporter assay (as described herein). It is evident that gRNAs are flexible to sequence insertions on the 5′ and 3′ ends (as measured by retained HR inducing activity). Accordingly, aspects of the present disclosure are directed to tagging of small-molecule responsive RNA aptamers that may trigger onset of gRNA activity, or gRNA visualization. Additionally, aspects of the present disclosure are directed to tethering of ssDNA donors to gRNAs via hybridization, thus enabling coupling of genomic target cutting and immediate physical localization of repair template which can promote homologous recombination rates over error-prone non-homologous end-joining.
[0093] The following references identified in the Examples section by number are hereby incorporated by reference in their entireties for all purposes.
REFERENCES
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TECHNICAL FIELD
This invention deals with a kind of nanocomposite materials composed of transition metal nanoclusters and magnetic iron oxides nanoparticles, their preparation methods and applications, especially the application as catalysts for the selectively catalytic hydrogenation of aromatic halonitro compounds to aromatic haloamines.
BACKGROUND TECHNOLOGY
Transition metal and alloy nanoclusters are nanoscopic materials with significant value of applications, which can be used to develop various functional materials and devices (Y Wang, Y. G Wei, “Metal Nanoclusters” (chapter) in: H. S, Nalwa (Ed.), Encyclopedia of Nanoscience and Nanotechnology , Vol. 5, pp. 337-367, 2004, American Scientific Publishers). The inventors of the present invention had invented a kind of “unprotected” noble metal and alloy nanoclusters, as well as the method for preparing the same.
These metal nanoclusters, stabilized only with simple ions and organic solvent molecules, have small particle sizes and narrow size distributions, and can be produced in a large scale. Moreover, the “unprotected” metal nanoclusters can be conveniently separated as precipitates from the original dispersions and purified, which can be then re-dispersed into many kinds of organic solvents to form stable metal colloidal solutions (Y. Wang, J. W. Ren, K. Deng, L. L. Gui, Y. Q. Tang, Chem. Mater., 2000, 12, 1622; Chinese Patent, ZL 99100052.8). These metal nanoclusters have been used to synthesize catalysts (Y. Wang, et al., J. Catal., 2004, 222, 493), catalytic electrodes for fuel cells (S. Mao, G Mao, “Supported Nanoparticle Catalyst”, USA Patent, US 2003/0104936, A1, Jun. 5, 2003; Q. Xin, et al., App. Catal. B, 2003, 46, 273), and hydrogen sensors (Y. Wang, et al., Chem. Mater., 2002, 14, 3953), etc.
γ-Fe 2 O 3 and Fe 3 O 4 are two kinds of well known magnetic iron oxides, both of them have the cubic inverse spinel crystal structure. They can transform to each other in specific conditions. For example, the oxidation of Fe 3 O 4 at about 523 K can produce γ-Fe 2 O 3 , indicating that γ-Fe 2 O 3 is more stable than Fe 3 O 4 . Different from the conventional ferromagnetic iron oxides materials with large particle sizes, upon decreasing the particle size to some extent, the iron oxides nanoparticles may exhibit special electronic, magnetic and optical properties. These unique properties endow the iron oxides nanoparticles with extensive application value in the fields of ultrahigh density data storage, bio-separation, controllable release of medicine, and wave-absorption materials. Currently, the most common method for industrial production of γ-Fe 2 O 3 is firstly preparing the ferric hydroxide precursor, followed by calcining the precursor at high temperature resulting in α-Fe 2 O 3 . Fe 3 O 4 is then produced by the reduction of α-Fe 2 O 3 with reductive gases, and then oxidized to γ-Fe 2 O 3 at high temperature. The required temperature in the preparation process is usually higher than 523 K. using γ-Fe 2 O 3 and Fe 3 O 4 materials prepared in such a high-temperature method, it is difficult to fabricate nanoscopic materials with small sizes and excellent performances.
The combination of metal nanoclusters and oxide nanoparticles can endow the composite materials with various properties. Many effective methods have been developed for immobilizing metal nanoclusters onto support particles, such as the impregnation method, reduction-deposition method, adsorption of protected metal colloidal particles, coordination capture method, deposition method, and the encapsulation method, etc. Due to the different microstructures of the metal-inorganic oxide composite materials derived from dissimilar preparation methods, catalysts with the same chemical compositions may exhibit obviously different catalytic properties. The composition, structure, particle size and size distribution of nanocomposites can also significantly affect their catalytic properties.
The immobilization of protected metal colloidal particles (Y. Wang, et al., J. Chem. Soc. Chem. Commun, 1989, 1878) or the encapsulation technique (C. Lange, et al., Catal. Lett., 1999, 58, 207; A. Martino, et al., J. Catal., 1999, 187, 30; A. G Sault et al., J. Catal., 2000, 191, 474; H. Bönnemann, et al., Eur: J. Inorg. Chem, 2000, 5, 819; Top. Catal., 2002, 18, 265; G. A. Somorjai, et al., Chem. Mater., 2003, 15, 1242; J. Zhu, et al., Langmuir, 2003, 19, 4396) can be used to synthesize the metal-inorganic oxide nanocomposites. In the encapsulation technique, the inorganic oxides of alumina or silica, prepared by the in suit hydrolysis of the corresponding metal-alcohol salts [M(RO) n ], are usually employed to encapsulate the metal colloidal particles protected by polymer, surfactant or coordination ligand. In order to obtain a close contact of the metal nanoparticles with inorganic supports, organic stabilizers originally adsorbed on the metal nanoclusters have to be removed by extraction or pyrolysis. This process may cause the aggregation of the metal nanoclusters, resulting in the difficulty in controlling the structure of the metal-inorganic oxide nanocomposites.
Seino et al. synthesized a kind of polyvinyl alcohol-metal-iron oxide magnetic nanocomposite materials by the photo-induced (using γ-irradiation) reduction of metal ions in aqueous solutions containing polyvinyl alcohol (PVA), and depositing the produced PVA-protected Au, Pt, Pd nanoclusters on commercially available γ-Fe 2 O 3 particles with an average diameter of 26 nm or Fe 3 O 4 particles with an average diameter of 100 nm ( Scripta Materalia, 2004, 51, pp. 467-472). In this synthesis method, the concentration of iron oxides was relatively low (about 1 g/l), so the synthesis efficiency was not very high. On the other hand, the particle size of metal nanoclusters was dependent on the concentration of iron oxides particles. When Fe 3 O 4 particles were used as the support, almost all of the metal particles deposited on the support were larger than 5 nm in size. In addition, the dispersion status of the oxide particles in the dispersion also affected the particle size of the deposited metal particles. Moreover, a part of PVA-protected Pt and Pd colloidal particles could not be adsorbed onto the iron oxides support.
Aromatic haloamines are important organic intermediates in the synthesis of dyes, pesticides, herbicides, medicines and special polymer materials. The hydrogenation of aromatic halonitro compounds to corresponding aromatic haloamines is one of important processes of chemical industry. It is a challenge in this synthesis industry to prevent the hydrogenolysis of the carbon-halogen bond in the haloaromatics, while maintaining the high catalytic activity of the catalysts for the hydrogenation of the aromatic halonitro compounds, especially when the conversion of the substrates is near 100%. If other electron-donating groups exist in the aromatic ring of the products, the hydrodehalogenation would become more serious (R. J. Maleski, et al., Eastman Chemical Co.) U.S. Pat. No. 6,034,276, (2000, 3, 7), WO 00/56698, 2000, 9, 2).
Over traditional metal catalysts (for example, Pt/C, Pd/C or Raney Ni), the hydrogenation of aromatic halonitro compounds was always companied by the hydrodehalogenation side reaction. Dehalogenation in the hydrogenation of bromine- or iodine-substituted aromatic nitro compounds is more serious than that in the case of aromatic chloronitro compounds. The order of susceptibility to hydrogenolysis for halogen-carbon bonds in aromatic halonitro compounds is I>Br>Cl>F (J. R. Kosak, in: Catalysis in Organic Syntheses , Academic Press, New York, 1980, pp. 107-117).
JP 2004277409-A (MITSUI CHEM. INC., JAPAN, 2004), disclose a technique for suppressing the hydrodechlorination of ortho-chloroaniline (o-CAN) over a Pt/C catalyst by charging 9.8 MPa of CO 2 into the reaction system, which achieve a selectivity of 99.7 mol % to O-CAN. Obviously, this technology need highly expensive reactors, and could not completely suppress the dechlorination side reaction.
Over a Pt/TiO 2 catalyst in a strong metal-support interaction state, the selective hydrogenation of para-chloronitrobenzene (p-CNB) was investigated under atmosphere pressure. When the conversion of p-CNB was less than 99.7%, the selectivity to para-chloroaniline (p-CAN) could reach 99.3%, which was the best selectivity in publications over Pt-based heterogeneous catalysts (B. Coq, A. Tijani, R. Dutartre, F. Figueras, J. Mol. Catal. A, 1993, 79, 253). However, after the complete conversion of the p-CNB substrate, the dechlorination rate of p-CAN increased rapidly. It is difficult to precisely control the reaction process in industrial production; thereby it is difficult to efficiently produce aromatic haloamines with high purity by using this catalyst.
Adding dechlorination inhibitors into the reaction system is also a method for suppressing the hydrodechlorination side reaction. EP473552-A (Baurneister, et al., 1992) described that in the hydrogenation of 2,4-dinitrochlorobenzene (2,4-DNCB) over a Pt/C catalyst modified with formamidine acetate, the selectivity to 4-chloro-m-phenylenediamine (4-CPDA) could reach 98% at complete conversion of the substrate.
DESCRIPTION OF THE INVENTION
The purpose of the present invention is providing a kind of nanocomposite materials composed of transition metals nanoclusters and magnetic iron oxides nanoparticles, and their preparation methods.
The invented transition metals-magnetic iron oxides nanocomposite materials are essentially composed of transition metals or their alloys nanoparticles with particle sizes ranging from 0.7 to 5 nm and magnetic iron oxides nanoparticles having sizes ranging from 5 to 50 nm. The total contents of the related transition metals or alloys in the related nanocomposite materials range from 0.1-30 wt. %. The related magnetic iron oxides include γ-Fe 2 O 3 , Fe 3 O 4 , the composite derived from part reduction of γ-Fe 2 O 3 , or the composite derived from part oxidation of Fe 3 O 4 .
The said composite derived from part reduction of γ-Fe 2 O 3 was obtained by partly reducing the related transition metal-γ-Fe 2 O 3 nanocomposite at 278-473 K in the presence of the reductants including hydrogen, glycolic acid, alcohol, aldehyde, etc. The said composite derived from part oxidation of Fe 3 O 4 was obtained by partly oxidating the related transition metal-Fe 3 O 4 nanocomposite at 313-523 K in the presence of oxygen.
In the present invention, typical transition metals are selected from Pt, Ru, Rh or Ir, etc. Typical transition metal alloys are selected from discretional two or more elements of Pt, Pd, Rh, Ru, Ir and Os. Typical particle sizes of the related magnetic iron oxides nanoparticles range from 5 to 25 nm.
The invented transition metals-magnetic iron oxides nanocomposite materials can be prepared by the following two methods:
The first method comprises the steps of:
1) preparing transition metal colloids: dissolving at least one kinds of soluble salts or acids containing the related transition metals into an alcohol solution or alcohol/water mixture to form a solution of transition metal compounds with concentration of 0.01-100 g/l, and adding an alcohol solution, or aqueous solution, or alcohol/water mixture of alkali metal hydroxides or alkaline-earth metal hydroxides into the said solution of the transition metal compounds, then heating the obtained mixture at 343-473 K to produce a colloidal solution of transition metal nanoclusters. The typical molar ratio of alkali metal hydroxides or alkaline-earth metal hydroxides to the salts or acids containing the said transition metals is in the range from 3 to 30. Typical alcohols are selected from alcohols containing one, or tow, or three hydroxyl groups and 1-8 carbon atoms, and unitary methoxyl or ethoxyl derivatives of the alcohols containing two or three hydroxyl groups and 1-8 carbon atoms. The typical volume content of water in the alcohol/water mixtures is 0-50%;
2) preparing ferric hydroxide colloids: forming a precipitate of ferric hydroxide by adding an alkaline solution into a solution containing ferric (Fe 3+ ) salts to adjust the pH value to 4-12, and peptizing the obtained precipitate in peptizing agents to produce a colloidal solution of ferric hydroxide with a concentration of 1-300 g/l. The said peptizing agents are selected from ferric chloride solution, ferric nitrate solution and hydrochloric acid;
3) preparing nanocomposite materials composed of transition metals nanoclusters and magnetic iron oxides nanoparticles: mixing the transition metal colloidal solutions prepared in step 1) and the ferric hydroxide colloidal solutions prepared in step 2) at mass ratios of metal colloidal solution to ferric hydroxide colloidal solution of 1:3-1:13400, and heat treating the mixture at 313-523 K for 1-200 h, then drying the obtained precipitates at 278-523 K to provide the related nanocomposite materials composed of transition metals nanoclusters and magnetic iron oxides nanoparticles.
The second method comprises the steps of:
1) preparing transition metal colloids: (A) dissolving at least one kinds of soluble salts or acids containing the related transition metals into an alcohol solution or alcohol/water mixture to form a solution of transition metal compounds with concentration of 0.01-100 g/l, and adding an alcohol solution, or aqueous solution, or alcohol/water mixture of alkali metal hydroxides or alkaline-earth metal hydroxides into the said solution of the transition metal compounds. The typical molar ratio of alkali metal hydroxides or alkaline-earth metal hydroxides to the salts or acids containing the said transition metals is in the range from 3 to 30. Typical alcohols are selected from alcohols containing one, or tow, or three hydroxyl groups and 1-8 carbon atoms, and unitary methoxyl or ethoxyl derivatives of the alcohols containing two or three hydroxyl groups and 1-8 carbon atoms. The typical volume content of water in the alcohol/water mixtures is 0-50%; (B) heating the obtained mixture at 343-473 K, and adding an acidic aqueous solution to form a precipitate of transition metal nanoclusters, then dispersing the said precipitate into ethylene glycol solutions of alkali metal or alkaline-earth metal hydroxides, or into organic solvents, to produce a colloidal solution of transition metal nanoclusters. Typical organic solvents are selected from alcohols containing tow or three hydroxyl groups and 1-8 carbon atoms, ketone, 1,4-dioxane, DMSO, THF and DMF;
2) preparing ferric hydroxide colloids: forming a precipitate of ferric hydroxide by adding an alkaline solution into a solution containing ferric (Fe 3+ ) salts to adjust the pH value to 4-12, and peptizing the obtained precipitate in peptizing agents to produce a colloidal solution of ferric hydroxide with a concentration of 1-300 g l. The said peptizing agents are selected from ferric chloride solution, ferric nitrate solution and hydrochloric acid;
3) preparing nanocomposite materials composed of transition metals nanoclusters and magnetic iron oxides nanoparticles: mixing the transition metal colloidal solutions prepared in step 1) and the ferric hydroxide colloidal solutions prepared in step 2) at mass ratios of metal colloidal solution to ferric hydroxide colloidal solution of 1:3-1:13400, and adding one or several kinds of organic reductants into the mixture, then heat treating the said mixture at 313-523 K for 1-200 h, followed by drying the obtained precipitate at 278-523 K to provide the related nanocomposite materials composed of transition metals nanoclusters and magnetic iron oxides nanoparticles. The related organic reductants are selected from formaldehyde, glycolic acid, sodium glycolate, isopropyl alcohol, glyoxal, oxalic acid and hydrogen. The typical molar ratio of organic reductants to ferric hydroxide is 0.1-10.
In the two preparation methods described above, soluble salts or acids containing the related transition metals in step 1) are selected from salts or acids containing Pt, Pd, Ru, Rh, Os and Ir.
In step 2), the concentration of the related Fe 3+ salts in the solutions is 0.01-4 mol/l; the ferric salts are selected from ferric sulfate, ferric nitrate, ferric chloride, etc. Typical alkalis include ammonia, potassium hydroxide, sodium hydroxide, lithium hydroxide, tetramethylammonium hydroxide, etc; the typical temperature for precipitating ferric hydroxide is 278-370 K; typical concentration of peptizing agents is in the range of 0.01-2 mol/l; typical peptization temperature is 278-373 K.
In step 3), the heat treating methods include solvothermal method, beating and refluxing method, and microwave irradiation method; the drying processes can be conducted in the following manners: drying in vacuum can provide the nanocomposite materials composed of transition metal nanoclusters and Fe 3 O 4 nanoparticles; oxidation drying in oxygen-containing atmosphere can provide the nanocomposite materials composed of transition metal nanoclusters and γ-Fe 2 O 3 nanoparticles; part-oxidation drying in oxygen-containing atmosphere can provide the nanocomposite materials composed of transition metal nanoclusters and magnetic iron oxides nanoparticles, the said magnetic iron oxides are the composite produced by partly oxidating Fe 3 O 4 in the transition metal-Fe 3 O 4 nanocomposite. Moreover, the related nanocomposite materials composed of transition metal nanoclusters and magnetic iron oxides nanoparticles can also be obtained by partly reducing the transition metal-γ-Fe 2 O 3 nanocomposite materials at 278-473 K in the presence of the reductants selected from hydrogen, glycolic acid, alcohol and aldehyde, the said magnetic iron oxides are the composite produced by partly reducing γ-Fe 2 O 3 in the transition metal-γ-Fe 2 O 3 nanocomposite materials.
The other purpose of the present invention is to provide the application of the invented transition metals-magnetic iron oxides nanocomposite materials.
Studies of the inventors of the present invention showed that the nanocomposite materials composed of the transition metal nanoclusters and magnetic iron oxides nanoparticles exhibited excellent catalytic properties, especially the high catalytic activity and superior selectivity in the selective hydrogenation of aromatic halonitro compounds. Moreover, the magnetic property of the nanocomposite material provides a convenient route for separating the catalysts from the reaction system in an applied magnetic field.
Over the invented nanocomposite catalysts, the hydrogenation of many aromatic halonitro compounds, such as halonitrobenzenes, halodinitrobenzenes and halonitrobiphenyl, can be conducted with very high selectivity, i.e. the hydrodehalogenation of the corresponding aromatic haloamine products would not occur over these catalysts. Generally, the hydrogenation conditions are as follows: temperature, 273-393 K; pressure of hydrogen, 0.1-10 MPa. The typical solvents used in the hydrogenation can be selected from alcohols or other organic solvents such as THF, DMSO and toluene. When the reaction is complete, the catalyst can be recovered from the reaction system by magnetic separation, centrifugation or filtration, and be reused.
The typical structures of aromatic halonitro compounds mentioned above are shown as follows:
In Scheme (I), X=Cl, Br or I; Y=H, R, COOR, RO, Cl, Br, I, NO 2 or NH 2 (R is saturated alkyl of C 1 -C 4 );
In Scheme (II), X=Cl, Br or I; X′, Y, Y′=H, R, COOR, RO, Cl, Br or I; Z=H, NO 2 or NH 2 (R is saturated alkyl of C 1 -C 4 ).
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a transmission electron microscope (TEM) image of Pt nanoclusters (Example 1).
FIG. 2 is a scanning transmission electron microscope (STEM) image of the Pt/γ-Fe 2 O 3 nanocomposite according to the present invention (Example 1).
FIG. 3 is an energy dispersive X-ray (EDX) pattern of the Pt/γ-Fe 2 O 3 nanocomposite according to the present invention (Example 1).
FIG. 4 is a Raman spectrum of the Pt/γ-Fe 2 O 3 nanocomposite according to the present invention (Example 1).
FIG. 5 is a Raman spectrum of the Pt/Fe 3 O 4 nanocomposite according to the present invention (Example 3).
EXAMPLES
Objects and advantages of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this invention.
Section 1
Examples for the Preparation of Nanocomposite Materials
Example 1
Preparation of Pt/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Pt Loading
1.0 g of hexachloroplatinate hexahydrate (H 2 PtCl 6 .6H 2 O) was dissolved into 50 ml of ethylene glycol (EG), followed by addition of 50 ml of EG solution containing NaOH (0.5 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 453 K for 3 h, with a nitrogen flow passing through the reaction system. A homogeneous, dark-brown colloidal solution of “unprotected” Pt nanoclusters (Pt: 3.75 g/l) was obtained. The average diameter of the prepared Pt nanoclusters was determined to be 2.0 nm by TEM measurements.
An aqueous solution of ammonia (10%) was added dropwise into a solution of ferric chloride (FeCl 3 ) in 100 ml of water (4%) to adjust the pH value to about 7.5, after ageing for 5 min, the produced precipitate of ferric hydroxide was filtered, washed to remove Cl − , and peptized in 30 ml of an aqueous solution of FeCl 3 (4%) by stirring and slightly heating under 323 K, resulting in a colloidal solution of ferric hydroxide, which was kept at room temperature for utilization.
2.6 ml of the Pt colloidal solution was added dropwise into the prepared ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 353 K for 72 h. A magnetic precipitate was produced, which was separated by filtration, washed to remove Cl − , dried and oxidized at 353 K in air for 48 h to produce the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt. The average diameter of γ-Fe 2 O 3 nanoparticles was determined to be 16 nm by TEM.
FIG. 1 shows the TEM image of the Pt nanoclusters prepared in Example 1. FIG. 2 shows the STEM image of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt. FIG. 3 shows the EDX pattern of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt. The above characterization results illustrated that the Pt nanoclusters were well dispersed in the matrix of the γ-Fe 2 O 3 nanoparticles without obvious aggregation. FIG. 4 shows the Raman spectrum of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt, demonstrating that iron oxide in the nanocomposite is γ-Fe 2 O 3 .
Example 2
Preparation of Pt/γ-Fe 2 O 3 Nanocomposite with 30 wt. % of Pt Loading
1.0 g of H 2 PtCl 6 .6H 2 O was dissolved into 50 ml of EG, followed by addition of 125 ml of EG/H 2 O (4:1, v:v) solution containing Ba(OH) 2 (0.1 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 433 K for 3 h under flowing nitrogen to produce a colloidal solution of “unprotected” Pt nanoclusters (Pt: 3.75 g/l). The average diameter of the obtained Pt nanoclusters is 3.0 nm.
An aqueous solution of ammonia (10%) was added dropwise into a solution of FeCl 3 in 100 ml of water (4%) to adjust the pH value to about 8.0, after ageing for 3 min, the produced precipitate of ferric hydroxide was then filtered, washed to remove Cl − , and peptized in 30 ml of an aqueous solution of FeCl 3 (4%) by stirring and slightly heating under 323 K, resulting in a colloidal solution of ferric hydroxide, which was kept at room temperature for utilization.
78.0 ml of the Pt colloidal solution was added dropwise into the prepared ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 353 K for 72 h. A magnetic precipitate was produced, which was separated by filtration, washed to remove Cl − , and dried at 353 K in air for 48 h to produce the Pt/γ-Fe 2 O 3 nanocomposite containing 30 wt. % of Pt. Particle size analyses showed that the average diameter of γ-Fe 2 O 3 nanoparticles is 9 nm.
Example 3
Preparation of Pt/Fe 3 O 4 Nanocomposite with 3 wt. % of Pt Loading
Colloidal solutions of Pt nanoclusters and ferric hydroxide nanoparticles were prepared as in Example 1. The Pt/Fe 3 O 4 nanocomposite was prepared as follows: 7.8 ml of the Pt colloidal solution was added dropwise into 30 ml of the ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 353 K for 72 h. A magnetic precipitate was produced, which was separated by a filtration, washed to remove Cl − , and dried at 353 K in vacuum to produce the Pt/Fe 3 O 4 nanocomposite containing 3 wt. % of Pt. Particle size analyses showed that the average diameter of Fe 3 O 4 nanoparticles is 16 nm. FIG. 5 shows the Raman spectrum of the Pt/Fe 3 O 4 nanocomposite containing 3 wt. % of Pt, indicating that iron oxide in the nanocomposite is Fe 3 O 4 .
Example 4
Preparation of Pt/Fe 3 O 4 Nanocomposite with 0.1 wt. % of Pt Loading
0.1 g of H 2 Pt/Cl 6 .6H 2 O was dissolved into 50 ml of EG, followed by addition of 50 ml of EG solution containing NaOH (0.05 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 433 K for 3 h to produce a colloidal solution of “unprotected” Pt nanoclusters (Pt: 0.375 g/l). Particle size analyses showed that the average diameter of the obtained Pt nanoclusters is 1.0 nm.
An aqueous solution of ammonia (10%) was added dropwise into a solution of FeCl 3 in 200 ml of water (2%) to adjust the pH value to about 12, after ageing for 10 min, the produced precipitate of ferric hydroxide was then separated by filtration, washed to remove Cl − , and peptized in 60 ml of an aqueous solution of FeCl 3 (2%) by stirring and heating under 363 K, resulting in a colloidal solution of ferric hydroxide, which was kept at room temperature for utilization.
2.6 ml of the Pt colloidal solution was added dropwise into the ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 413 K for 160 h. A magnetic precipitate was produced, which was separated by filtration, washed to remove Cl − , and dried in vacuum for 48 h to produce the Pt/Fe 3 O 4 nanocomposite containing 0.1 wt. % of Pt. Particle size analyses showed that the average diameter of Fe 3 O 4 is 45 nm.
Example 5
Preparation of Ru/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Ru Loading
1.0 g of RuCl 3 .3H 2 O was dissolved into 50 ml of ethylene glycol monomethyl ether, followed by addition of 50 ml of EG/H 2 O (1:1, v:v) solution containing KOH (0.5 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 373 K for 3 h to produce a colloidal solution of “unprotected” Ru nanoclusters (Ru: 3.75 g/l). Particle size analyses showed that the average diameter of the obtained Ru nanoclusters is 1.3 nm.
An aqueous solution of tetramethylammonium hydrate (10%) was added dropwise into a solution of ferric nitrate in 150 ml of water (4%) to adjust the pH value to about 4, after ageing for 3 min, the produced precipitate of ferric hydroxide was then separated by filtration, washed, and peptized in 30 ml of a dilute aqueous solution of HCl (1%) by stirring and slightly heating under 333 K, resulting in a colloidal solution of ferric hydroxide, which was kept at room temperature for utilization.
2.6 ml of the Ru colloidal solution was added dropwise into the ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 313 K for 72 h. A black precipitate was produced, which was separated by filtration, washed to remove Cl − , dried and oxidized at 353 K in air for 48 h to produce the Ru/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Ru. Particle size analyses showed that the average diameter of γ-Fe 2 O 3 nanoparticles is 6 nm.
Example 6
Preparation of Pt/γ-Fe 2 O 3 Nanocomposite with 5 wt. % of Pt Loading
Colloidal solutions of Pt nanoclusters and ferric hydroxide nanoparticles were prepared as in Example 1. The Pt/γ-Fe 2 O 3 nanocomposite was prepared as follows: 13 ml of an aqueous solution of HCl (1 mol/l) was added into 13.1 ml of the Pt colloidal solution (3.75 g/l) to form a precipitate of the Pt nanoclusters, which was separated by centrifugation and then redispersed into 5.6 ml EG solution of NaOH (0.5 mol/l), followed by the addition of 0.3 g glycolic acid. The obtained colloidal solution of Pt nanoclusters was added dropwise into 30 ml of the ferric hydroxide colloidal solution under vigorously stirring, the mixture was refluxed at 373 K for 72 h. The produced black precipitate was filtered, washed, dried and oxidized at 353 K in air for 48 h to produce the Pt/γ-Fe 2 O 3 nanocomposite containing 5 wt. % of Pt. Calcining the obtained sample at 773 K for 2 h to produce the calcined Pt/γ-Fe 2 O 3 nanocomposite containing 5 wt. % of Pt. X-ray diffraction (XRD) patterns and other measurements demonstrated that iron oxide in the nanocomposite is γ-Fe 2 O 3 .
Example 7
Preparation of Pt/Magnetic Iron Oxides Nanocomposite with 3 wt. % of Pt Loading
Colloidal solutions of Pt nanoclusters and ferric hydroxide nanoparticles were prepared as in Example 1. The Pt/magnetic iron oxides nanocomposite was prepared as follows: 7.8 ml of the Pt colloidal solution (3.75 g/l) was added into 30 ml of the ferric hydroxide colloidal solution under stirring. The mixture was then heated and refluxed under N 2 for 24 h. The obtained precipitate was filtered, washed, dried and oxidized at 333 K in air for 12 h to produce the nanocomposite composed of Pt/γ-Fe 2 O 3 and Pt/Fe 3 O 4 with 3 wt. % of Pt loading. Raman spectra proved that the nanocomposite consisted of γ-Fe 2 O 3 and Fe 3 O 4 .
Example 8
Preparation of Pt/Fe 3 O 4 Nanocomposite with 6 wt. % of Pt Loading
Colloidal solutions of Pt nanoclusters and ferric hydroxide nanoparticles were prepared as in Example 1. The Pt/Fe 3 O 4 nanocomposite was prepared as follows: 15 ml of an aqueous solution of HCl (1 mol/l) was added into 15.6 ml of the Pt colloidal solution (3.75 g/l) to produce a precipitate of the Pt nanoclusters, which was separated by centrifugation and then redispersed into 9 ml THF solution of KOH (0.1 mol/l). The obtained colloidal solution of Pt nanoclusters was added dropwise into 30 ml of the ferric hydroxide colloidal solution under vigorously stirring, followed by the addition of 10 ml THF solution containing 0.5 g of sodium glycolate. The mixture was heated by microwave irradiation under stirring for 2 h. The product was filtered, washed, and dried at 353 K in vacuum for 24 h to produce the Pt/Fe 3 O 4 nanocomposite containing 6 wt. % of Pt.
Example 9
Preparation of Pt—Ru/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Metal Loading and a Pt/Ru Molar Ratio of 1:1
0.5179 g of H 2 PtCl 6 .6H 2 O and 0.2073 g of RuCl 3 .3H 2 O were dissolved into 25 ml of EG, followed by the addition of 25 ml EG solution containing NaOH (1.0 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 453 K for 3 h to produce a colloidal solution of “unprotected” Pt—Ru alloy nanoclusters, wherein the total metal concentration of Pt—Ru is 5.92 g/l.
An aqueous solution of ammonia (10%) was added dropwise into a solution of FeCl 3 in 2.5 ml of water (10 mol/l) to adjust the pH value to about 7.5, after ageing for 5 min the produced precipitate of ferric hydroxide was then filtered, washed to remove Cl − , and peptized in 30 ml aqueous solution of FeCl 3 (1 mol/l) by stirring and slightly heating, resulting in a colloidal solution of ferric hydroxide, which was kept at room temperature for utilization.
1.65 ml of the Pt—Ru alloy colloidal solution was added into the ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 393 K for 72 h. A black precipitate was produced, which was filtered, washed, dried and oxidized at 393 K in air for 48 h to produce the Pt—Ru/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Ru molar ratio of 1:1.
Example 10
Preparation of Pt—Ir/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Metal Loading and a Pt/Ir Molar Ratio of 1:1
0.5179 g of H 2 PtCl 6 .6H 2 O and 0.2986 g of IrCl 3 .3H 2 O were dissolved into 50 ml glycerol, followed by the addition of 50 ml glycerol solution containing NaOH (0.6 mol/l). After stirring at room temperature for 5 min, the mixture was refluxed at 453 K for 3 h to produce a colloidal solution of “unprotected” Pt—Ir alloy nanoclusters, wherein the metal total concentration of Pt—Ir is 3.87 g/l.
An aqueous solution of KOH (2%) was added dropwise into a solution of FeCl 3 in 25 ml of water (1 mol/l) to adjust the pH value to about 7.53 after ageing for 5 min, the produced precipitate of ferric hydroxide was then filtered, washed to remove Cl − , and peptized in 30 ml aqueous solution of FeCl 3 (4%) by stirring at room temperature, resulting in a colloidal solution of ferric hydroxide.
2.52 ml of the Pt—Ir alloy colloidal solution was added dropwise into the ferric hydroxide colloidal solution under stirring. The mixture was then heated in a Teflonlined autoclave at 353 K for 72 h. A black precipitate was produced, which was filtered, washed to remove Cl − , dried and oxidized at 423 K in air for 48 h to produce the Pt—Ir/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Ir molar ratio of 1:1.
Example 11
Preparation of Rh/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Rh Loading
Replacing H 2 PtCl 6 .6H 2 O in Example 1 with RhCl 3 .3H 2 O of the same molar content, and using the same preparation method to produce the Rh/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Rh.
Example 12
Preparation of Pt—Pd/γ-Fe 2 O 3 Nanocomposite with 1 wt. % of Metal Loading and a Pt/Pd Molar Ratio of 4:1
Replacing RuCl 3 .3H 7 O in Example 9 with PdCl 2 .xH 2 O, keeping the Pt/Pd molar ratio to be 4:1, and using the same preparation method to produce the Pt—Pd/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Pd molar ratio of 4:1.
Example 13
Preparation of Pt/Magnetic Iron Oxide Nanocomposite
Heating the red-brown Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt prepared in Example 1 at 333 K under hydrogen for 60 min to produce a black Pt/magnetic iron oxide nanocomposite. Raman analyses revealed that the obtained nanocomposite consisted of γ-Fe 2 O 3 and Fe 3 O 4 .
Selecting two or several kinds of soluble salts of Pt, Rh, Ru, Ir, Os and Pd, and adopting the similar methods as described in Example 1-13, can prepare nanocomposite materials composed of alloy nanoclusters of the selected transition metals and the magnetic iron oxides nanoparticles.
Section 2
Examples for the Application of Nanocomposite Materials in Catalysis
The nanocomposite materials composed of transition metal nanoclusters and magnetic iron oxides nanoparticles according to the present invention exhibited high catalytic activity, excellent stability and superior selectivity in the hydrogenation of chlorine-, bromine-, and iodine-substituted aromatic nitro compounds (such as halonitrobenzenes and halonitrobiphenyl containing several kinds of substituted groups) to the corresponding aromatic haloamines. Over the invented nanocomposite catalysts, the selectivities to the corresponding aromatic haloamines can reach a level higher than 99.9% at 100% conversion of the aromatic halonitro compounds. It should be pointed out that even when the aromatic halonitro compounds were completely exhausted in these catalytic reactions, the coexistence of the present nanocomposite catalysts and the aromatic haloamines products under 0.1-4.0 MPa of hydrogen pressure will not cause the decrease in the selectivity to the desirable products. In other words, over these nanocomposite catalysts, the hydrodehalogenation side reactions in the catalytic reactions of interest are complete inhibited. Due to the fully suppression of the dehalogenation side reaction, the hydrogenation of the aromatic halonitro compounds can be conducted rapidly and completely under elevated hydrogen pressure, actualizing the aim of efficiently producing the corresponding aromatic haloamines with a high purity. Meanwhile, the separation process of the reaction products is also facilitated. The magnetic or super-paramagnetic property of the nanocomposite catalysts provides a convenient route for separating the catalysts from the reaction systems in an applied magnetic field.
In typical catalytic hydrogenation experiments, the invented magnetic transition metal-iron oxides nanocomposite materials were dispersed in suitable volume of organic solvents, activated under hydrogen ambience. Then organic solutions of the aromatic halonitro compound were added into the reactor to start the reaction. The obtained products were analyzed by gas chromatography (GC). After the reaction was complete, the catalyst was separated from the reaction system in an applied magnetic field and washed before reusing in the next cycle of the reaction. The catalyst separation can also be conducted by the conventional methods such as filtration or centrifugation. The reaction temperature was in a range from 273 to 393 K, and the pressure of hydrogen ranged from 0.1 to 10 MPa.
Example 14
Selective hydrogenation of o-chloronitrobenzene (o-CNB) over Pt/γ-Fe 2 O 3
1) Reaction Under 0.1 MPa of Hydrogen Pressure
The reaction was carried out in a 50-ml reactor with magnetic stirring at 333 K. Prior to the reaction, air in the system was replaced by hydrogen. 0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt prepared in Example 1 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of a methanol solution containing 13.0 mmol of o-CNB was added into the reactor to start the reaction. The products were analyzed by GC.
2) Reaction Under 2.0 MPa of Hydrogen Pressure
0.05 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt and 13.0 mmol of o-CNB were added into 25 ml of methanol in an autoclave, then the reaction was conducted at 333 K under 2.0 MPa of hydrogen pressure. The products were analyzed by GC.
3) Reaction Under 4.0 MPa of Hydrogen Pressure
0.05 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt and 13.0 mmol of o-CNB were added into 25 ml of methanol in an autoclave, then the reaction was conducted at 333 K under 4.0 MPa of hydrogen pressure. The products were analyzed by GC.
The catalytic activity and selectivity over the catalyst are listed in TABLE 1.
TABLE 1
H 2 pressure
Catalyst
Reaction time
Conversion
Reaction rate
Selectivity (%)
(MPa)
(g)
(min)
(%)
(mol o-CNB /mol Pt · s)
o-chloroaniline
aniline
0.1
0.20
95
100
0.22
>99.9
0.0
2.0
0.05
10
76.0
6.42
>99.9
0.0
0.05
10
89.4
7.55
>99.9
0.0
4.0
0.05
20
100
7.60
>99.9
0.0
0.05
240
100
—
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; o-CNB, 13.0 mmol.
Example 15
Selective Hydrogenation of p-CNB over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 2. After the reaction was complete, the catalyst was separated from the reaction system in an applied magnetic field, washed with methanol, and reused in the next cycle of reaction without obvious change in the catalytic properties.
TABLE 2
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.20
45.3
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
Example 16
Selective Hydrogenation of 2,4-dinitrochlorobenzene (2,4-DNCB) over Pt/γ-Fe 2 O 3
0.10 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of 2,4-DNCB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 3.
TABLE 3
Selectivity (%)
Catalyst
Reaction time
Conversion
Reaction rate
4-chloro-m-
(g)
(min)
(%)
(mol 2,4-DNCB /mol Pt · s)
phenylenediamine
m-phenylenediamine
0.10
80
100
0.052
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 2,4-DNCB, 1.27 mmol.
Example 17
Selective Hydrogenation of o-bromonitrobenzene (o-BNB) over Pt/γ-Fe 2 O 3
0.04 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was added into 100 ml of methanol solution containing o-BNB (0.10 mol/l), then the reaction was conducted at 303 K under 3.6 MPa of hydrogen pressure. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 4.
TABLE 4
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
o-bromoaniline
aniline
0.04
20
100
>99.0
0.0
Reaction conditions: methanol, 100 ml; temperature, 303 K; hydrogen pressure, 3.6 MPa; o-BNB, 10 mmol.
Example 18
Selective Hydrogenation of p-iodonitrobenzene (p-INB) over Pt/γ-Fe 2 O 3
0.15 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of THF, and activated at 303 K under 0.1 MPa of hydrogen pressure for 30 min, then 10 ml of THF solution containing p-INB (0.15 mol/l) was added into the reactor. The reaction was conducted at 303 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 5.
TABLE 5
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-iodoaniline
aniline
0.15
45
100
>99.0
0.0
Reaction conditions: THF, 15 ml; temperature, 303 K; hydrogen pressure, 0.1 MPa; p-INB, 1.5 mmol.
Example 19
Selective Hydrogenation of 3,4-dichloronitrobenzene (3,4-DCNB) over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of 3,4-DCNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 6.
TABLE 6
Selectivity (%)
Catalyst
Reaction time
Conversion
Reaction time
3,4-dichloro-
(g)
(min)
(%)
(mol 3,4-DCNB /mol Pt · s)
aniline
chloroaniline
aniline
0.20
30
100
0.068
>99.9
0.0
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 3,4-DCNB, 1.27 mmol.
Example 20
Selective Hydrogenation of 2-chloro-6-nitrotoluene over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of 2-chloro-6-nitrotoluene was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 7.
TABLE 7
Selectivity (%)
Catalyst
Reaction time
Conversion
3-chloro-2-
(g)
(min)
(%)
methylaniline
o-methylaniline
0.20
35
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 2-chloro-6-nitrotoluene, 1.27 mmol.
Example 21
Selective Hydrogenation of Methyl 4-chloro-3-nitrobenzoate over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of methyl 4-chloro-3-nitrobenzoate was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 8.
TABLE 8
Selectivity (%)
methyl
methyl
Catalyst
Reaction time
Conversion
4-chloro-3-amino-
3-amino-
(g)
(min)
(%)
benzoate
benzoate
0.20
50
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; methyl 4-chloro-3-nitrobenzoate, 1.27 mmol.
Example 22
Selective Hydrogenation of 4-chloro-3-nitro-methoxybenzene over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 30 ml of methanol solution containing 1.27 mmol of 4-chloro-3-nitro-methoxybenzene was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 9.
TABLE 9
Selectivity (%)
4-chloro-3-
3-amino-
Catalyst
Reaction time
Conversion
amino-methoxy-
methoxy-
(g)
(min)
(%)
benzene
benzene
0.20
55
100
>99.9
0.0
Reaction conditions: methanol, 35 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 4-chloro-3-nitro-methoxybenzene, 1.27 mmol.
Example 23
Selective Hydrogenation of 4-chloro-3-nitro-diphenyl over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of THF, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 30 ml of THF solution containing 1.27 mmol of 4-chloro-3-nitro-diphenyl was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 10.
TABLE 10
Selectivity (%)
Catalyst
Reaction time
Conversion
4-chloro-3-
3-amino-
(g)
(min)
(%)
amino-diphenyl
diphenyl
0.20
70
100
>99.9
0.0
Reaction conditions: THF, 35 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 4-chloro-3-nitro-diphenyl, 1.27 mmol.
Example 24
Selective Hydrogenation of 4-chloro-3-nitro-4′-methyldiphenyl over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of toluene, and activated at 383 K under 0.1 MPa of hydrogen pressure for 30 min, then 30 ml of toluene solution containing 1.27 mmol of 4-chloro-3-nitro-4′-methyldiphenyl was added into the reactor. The reaction was conducted at 383 K under vigorous stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 11.
TABLE 11
Selectivity (%)
4-chloro-3-
Catalyst
Reaction time
Conversion
amino-4′-
3-amino-4′-
(g)
(min)
(%)
methyldiphenyl
methyldiphenyl
0.20
70
100
>99.9
0.0
Reaction conditions: toluene, 35 ml; temperature, 383 K; hydrogen pressure, 0.1 MPa; 4-chloro-3-nitro-4′-methyldiphenyl, 1.27 mmol.
Example 25
Selective Hydrogenation of 4-chloro-3-nitro-4′-methyl-3′-nitro-diphenyl over Pt/γ-Fe 2 O 3
0.2 g of the Pt/γ-Fe 2 O 3 nanocomposite containing 1 wt. % of Pt was dispersed in 5 ml of THF, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 50 ml of THF solution containing 1.27 mmol of 4-chloro-3-nitro-4′-methyl-3′-nitro-diphenyl was added into the reactor. The reaction was conducted at 333 K under vigorous stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 12.
TABLE 12
Selectivity (%)
4-chloro-3-
amino-4′-
4-methyl-3-
Catalyst
Reaction time
Conversion
methyl-3′-
amino-3′-
(g)
(min)
(%)
amino-diphenyl
amino-diphenyl
0.20
90
100
>99.9
0.0
Reaction conditions: THF, 55 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; 4-chloro-3-nitro-4′-methyl-3′-nitro-diphenyl, 1.27 mmol.
Example 26
Selective Hydrogenation of p-CNB over the Pt/Magnetic Iron Oxides Nanocomposite
0.1 g of the Pt/magnetic iron oxides nanocomposite containing 3 wt. % of Pt prepared in Example 7 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 13.
TABLE 13
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.10
31
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
Example 27
Selective Hydrogenation of m-CNB over the Pt/Magnetic Iron Oxides Nanocomposite
0.2 g of the Pt/magnetic iron oxides nanocomposite prepared in Example 13 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of m-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 14.
TABLE 14
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
m-chloroaniline
aniline
0.20
43
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; m-CNB, 1.27 mmol.
Example 28
Selective Hydrogenation of p-CNB over Pt—Pd/γ-Fe 2 O 3
0.2 g of the Pt—Pd/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Pd molar ratio of 4:1 prepared in Example 12 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 15.
TABLE 15
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.20
41
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
Example 29
Selective Hydrogenation of p-CNB over Pt—Ru/γ-Fe 2 O 3
0.2 g of the Pt—Ru/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Ru molar ratio of 1:1 prepared in Example 9 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 16.
TABLE 16
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.20
58
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
Example 30
Selective Hydrogenation of p-CNB over Pt—Os/γ-Fe 2 O 3
0.2 g of the Pt—Os/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Os molar ratio of 20:1 prepared by the same method described in Example 9 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 17.
TABLE 17
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.20
79
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
Example 31
Selective Hydrogenation of p-CNB over Pt—Ir/γ-Fe 2 O 3
0.2 g of the Pt—Ir/γ-Fe 2 O 3 nanocomposite with 1 wt. % of metal loading and a Pt/Ir molar ratio of 1:1 prepared in Example 10 was dispersed in 5 ml of methanol, and activated at 333 K under 0.1 MPa of hydrogen pressure for 30 min, then 20 ml of methanol solution containing 1.27 mmol of p-CNB was added into the reactor. The reaction was conducted at 333 K under vigorously stirring. The products were analyzed by GC. The catalytic activity and selectivity over the catalyst are listed in TABLE 18.
TABLE 18
Catalyst
Reaction time
Conversion
Selectivity (%)
(g)
(min)
(%)
p-chloroaniline
aniline
0.20
62
100
>99.9
0.0
Reaction conditions: methanol, 25 ml; temperature, 333 K; hydrogen pressure, 0.1 MPa; p-CNB, 1.27 mmol.
The experimental results of this section show that, the nanocomposite catalysts according to the present invention possess high catalytic activity and superior selectivity for the hydrogenation of aromatic halonitro compounds to the corresponding aromatic haloamines. The hydrodehalogenation side reaction is fully inhibited successfully over the invented nanocomposite catalysts, indicating that these catalysts can be used for efficiently producing aromatic haloamines with a high purity.
INDUSTRIAL APPLICATION
In virtue of the catalytic function of the metal nanoclusters, the present invention succeeded in preparing a new kind of magnetic transition metals-iron oxides nanocomposite materials at relative low temperature. The main features of the preparation method according to the present invention are first to prepare the colloidal solutions of “unprotected” transition metal or alloy nanoclusters, which are then mixed with the colloidal solutions of ferric hydroxide nanoparticles to form complex sols, followed by the heat treatment in the presence of reductants, such as alcohol, aldehyde and glycolic acid. The obtained products are washed, dried or oxidized to produce the said nanocomposite materials composed of the transition metal nanoclusters and magnetic iron oxides nanoparticles.
The invented nanocomposite materials composed of transition metal nanoclusters and magnetic iron oxides nanoparticles can catalyze the hydrogenation of aromatic halonitro compounds to aromatic haloamines with very high selectivity. The hydrodehalogenation side reaction in the hydrogenation of aromatic halonitro compounds to aromatic haloamines was fully suppressed for the first time over the present nanocomposite catalysts. Moreover, due to the two or more functional components and the cooperative effect between the nanoparticles, the invented nanocomposite materials are of great value for application in the fields of catalyst, magnetic separation, wave-absorption materials, etc. | A composite material composed of nanoparticles of transition metal(s) and magnetic ferric oxide, a method of preparing the same, and uses of the same are provided. The composite material is substantially composed of nanoparticles of transition metal(s) or alloy thereof and nanoparticles of magnetic ferric oxide, the size of nanoparticles of transition metal(s) or alloy thereof is in the range of 0.7 to 5 nm, the size of nanoparticles of magnetic ferric oxide is in the range of 5 to 50 nm, and the amount of transition metal(s) or alloy thereof is in the range of 0.1 to 30 wt %, based on the total weight of composite material, the magnetic ferric oxide is gamma-Fe2O3, Fe3O4, complex obtained from gamma-Fe2O3 by partial reduction, or complex obtained from Fe3O4 by partial reduction. The composite material has a high reactivity and an extreme selectivity for industrial reaction of hydrogenating halogeno-nitro-aromaticics to obtain halogeno-arylamine, and has important industrial applicability because the problem such as hydrogenolysis-dehalogenation during preparing halogeno arylamine by hydrogenating halogeno-nitro-aromatics is fully resolved by using the composite materials. | 8 |
FIELD OF THE INVENTION
The invention relates to blood processing systems and apparatus. More specifically, the invention relates to blood processing apparatus such as centrifuges which are provided with improved spill sensors.
BACKGROUND OF THE INVENTION
Whole blood is separated by centrifugation into its various constituents, such as red blood cells, platelets, and plasma. Conventional blood processing methods use centrifuge equipment in association heaters that maintain the temperature of the processing system during the centrifuging process. Such systems have been provided with splash or spill detectors in the past that rely on a circuit being shorted by spilled blood to signal the existence of the spill.
SUMMARY OF THE INVENTION
The invention provides improved blood processing systems with a spill or splash detector that is fail safe in that the system is continuously monitored to ensure that the detector is operational. One aspect of the invention provides a blood processing assembly that includes a centrifuge having an enclosing housing, which may be provided with a heater and which housing contains a splash or spill detector that is provided with such fail safe characteristics by means of appropriate electronic circuits. It is an important object of the invention to provide a device that detects failure of a spill detecting system thus eliminating the need for verification of functionality by the operator.
In accordance with a further aspect of the invention, such circuits are provided using conventional and inexpensive components such as resistors or capacitors.
In accordance with a yet further related aspect of the invention, an open circuit is provided in the form of two parallel printed circuit conductors that are spaced apart a selected distance so that when a splash occurs within the confines of the housing a circuit is closed between the two parallel conductors. Such circuit is provided so that when a leak occurs, the circuit is closed, thereby triggering a message, sounding an alarm and/or stopping the centrifuge. The conductive strips form, in effect, electrodes that are insulated from each other and also from the surface on which they are mounted. Blood or other liquid from a leak in the centrifuge is thrown against the compartment wall and, thus, on the conductive strips. The blood causes a low resistance connection between the conductive strips. Thus current flows through the electrodes at a higher rate than that which flows through the fail--safe monitoring circuit, which in turn causes a message to be triggered and the machine to be stopped.
In accordance with the invention, a resistor or, alternatively, a capacitor is positioned between one end of each of the conductive strips so that a small amount of current continues to flow through the resistor or capacitor. This current flow is monitored, thus indicating that the system is functional. In the event of total failure of the system, the lack of this monitoring current is noted and an appropriate alarm or message indicating failure of the system is triggered.
Further features and advantages of the invention will become apparent from the following description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a centrifugal assembly that embodies the features of the invention;
FIG. 2 is a perspective view of the assembly of FIG. 1 showing the centrifuge chamber in the open position;
FIG. 3 is a sectional view of a centrifuge shown in FIG. 1 taken along Line 3--3 with parts broken away to show the compartment that houses the associated centrifuge;
FIG. 4 is a fragmentary side elevational view taken along Line 4--4 of FIG. 3 showing a splatter detector of this invention; and,
FIG. 5 is a diagrammatic view of a control circuit associated with the splatter detector.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 3 show a centrifugal processing system 10 that embodies the features of the invention. The system 10 can be used for processing various fluids. The system 10 is particularly well suited for processing whole blood and other suspensions of biological cellular materials. Accordingly, the illustrated embodiment shows the system 10 used for this purpose.
The system 10 includes a centrifuge assembly 12 (see FIG. 1) and a fluid processing assembly (not shown) used in association with the centrifuge assembly.
The centrifuge assembly 12 is intended to be a durable equipment item capable of long term, maintenance free use. The fluid processing assembly is a single use, disposable set loaded on the centrifuge assembly 12 at time of use in accordance with known practices. The operator removes the fluid processing assembly from the centrifuge assembly 12 upon the completing the procedure and discards it.
FIG. 2 shows a centrifuge or processing chamber 14 and containment housing 16 usable in association with the assembly 12. In use, the centrifuge assembly 12 rotates the processing chamber 14 to centrifugally separate blood components. The construction of the processing chamber 14 can vary, with numerous constructions being known in the art.
The processing assembly 12 includes an array of flexible tubing that forms a fluid circuit 18. The fluid circuit 18 conveys liquids to and from the processing chamber 14.
The fluid circuit 18 includes a number of containers 20. In use, the containers 20 fit on hangers within the centrifuge assembly 12 (see FIG. 3) to dispense and receive liquids during processing. Centrifuge 14 is rotationally driven by a motor 22.
The fluid circuit 18 includes one or more in line fluid processing containers and devices, as is known in the art, in association with pump and valve stations on the centrifuge assembly 12 to direct liquid flow among the multiple liquid sources and destinations during a blood processing procedure.
A portion of the fluid circuit 18 leading from the containers 20 is bundled together to form an umbilicus 24. The umbilicus 24 links the rotating parts of the processing assembly 12 with the nonrotating, stationary part of the processing assembly 12. The umbilicus 24 links the rotating and stationary parts of the processing assembly 12 without using rotating seals.
In the illustrated and preferred embodiment, the fluid circuit 18 preconnects the processing chamber 14, the containers 20, and other fluid processing parts of the system. The assembly 12 thereby forms an integral, sterile unit.
The umbilicus 24 consolidates the multiple fluid paths leading to and from the blood separation chamber. It provides a continuous, sterile environment for fluids to pass. In construction, the umbilicus 24 is flexible enough to function in the relatively small, compact operating space the centrifuge assembly 12 provides. Still, the umbilicus 24 is durable enough to withstand the significant flexing and torsional stresses imposed by the small, compact spinning environment, where rotation rates up to about 4000 revolutions per minute (RPM) can be encountered.
The processing chamber 14 can be variously constructed. For example, it can be constructed like the double bag processing chambers shown in Cullis et al. U.S. Pat. No. 4,146,172. Specific details of the construction of the processing chamber 14 and other components of the system are not essential to an understanding of the invention and can be also be found in copending U.S. patent application Ser. No. 07/965,074, filed Oct. 22, 1992 and entitled "Enhanced Yield Blood Processing Systems and Methods Establishing Vortex Flow Conditions," which is incorporated herein by reference.
The centrifuge assembly 12 includes a processing controller 246. The controller 246 governs the operation of the centrifuge assembly 12. The processing controller 246 preferably includes an integrated input/output terminal 248 as seen in FIG. 1), which receives and display information relating to the processing procedure.
The centrifuge 14 rotates about an axis within the compartment 16. As FIG. 2 shows, unlike conventional centrifuges, the rotational axis of the centrifuge 14 is not oriented perpendicular to the horizontal support surface. Instead, the rotational axis slopes in a plane outside a vertical plane. The centrifuge 14 is supported within the compartment 16 outside the vertical plane such that its rotating components lie near the access door 17 (see FIG. 2). In this way, opening the door 17 provides direct access to the rotating components of the centrifuge 14. The sloped orientation of rotational axis allows the centrifuge 14 to be mounted in a way that conserves vertical height.
The angled relationships established between the rotational axis of the centrifuge 14 and the plane of top panel 19 make it possible to place the rotating centrifuge components for access in a zone that lies between the knees and chest of the average person using the machine. These relationships also make it possible to place the stationary functional components such as pumps, sensors, detectors, and the like for access on the panel 19 by the user within the same zone. Most preferably, the zone lies around the waist of the average person.
Statistics providing quantitative information about the location of this preferred access zone for a range of people (e.g., Large Man, Average Man/Large Woman, Average Adult, Small Man/Average Woman, etc.) are found in the Humanscale™ Series Manuals (Authors: Niels Diffrient et al., a Project of Henry Dreyfuss Associates), published by the MIT Press, Massachusetts Institute of Technology, Cambridge, Mass.
These angled relationships established among the rotating and stationary components of the centrifuge assembly 12 provide significant ergonomic benefits that facilitate access to and operation of the assembly 12.
Further details of the chamber assembly are found in copending U.S. patent application Ser. No. 07/814,403, filed Dec. 23, 1991, and entitled "Centrifuge with Separable Bowl and Spool Elements Providing Access to the Separation Chamber," which is incorporated herein by reference. The centrifuge 14 made and operated according to the invention provides a small, compact operating environment. The compact operating environment leads to rates of rotation greater than those typically encountered in conventional blood centrifuges. As best seen in FIGS. 3 and 4, a splatter detector assembly 30 is provided on an interior wall of housing 16. In the event that blood is leaking, for example from containers 20 or from conduits 18 or connections thereof, it is important that the centrifuge be stopped and the problem remedied before excessive amounts of blood are lost within the interior of assembly 12 and leak into the surrounding area.
In the preferred embodiment shown in the drawings, the splatter detector assembly 30 consists of two splatter detectors 32 and 34. Each of these detectors consists of a pair of parallel electrodes, 36, 38 and 40, 42, respectively. A pair of electrodes is connected by means of a high resistance resistor 44 or 46, respectively. In the preferred embodiment the electrodes 36, 38, 40 and 42 may take the form of metallic strips on a non-conductive, for example plastic base. These strips may be in the form commonly used in printed circuits.
As further seen in FIG. 4, when droplets of a liquid such as blood are deposited, on the electrodes of the spill detector, a conductive flow path can be formed between electrode conductors 36, 38 or 40, 42. This enables a greater flow of current to pass through the circuit, thus triggering a message on the screen of processor 248, as well as cutting off the power driving the rotation of centrifuge 14. This enables the operator to open and clean the interior of assembly 12 and to remedy the problem.
As seen in FIG. 5, each of the detectors 32 and 34 has one end of each of its electrodes 36, 38 and 40,42 connected to terminals of a connector 58. One of these terminals is connected by capacitor 62 to an AC circuit 60. Circuit 60 serves to act as a sine wave or square wave generator for the detector circuit. The other electrode is ac coupled by another capacitor 66. The circuit is connected by a buffer circuit 66 to an amplifier 68 which serves as a half-wave rectifier. A third amplifier 70 serves as a low pass filter. An analog signal output 72 connects the circuit to outside monitoring circuits contained within controller 246. The circuit, thus, enables the monitoring of the small amounts of current flow through resistors 44 and 46 which tell processing controller 246 that each of the splatter detectors is operational. Subsequently, if a droplet of fluid 50 is present across either of the pairs of electrodes 36, 38 or 40, 42, a signal of greater amplitude is transmitted by output 72. This detection of the splatter then provides an appropriate warning message on input/output terminal 248. In accordance with the preferred embodiment, controller 246 also causes the flow of power to drive motor 22 to cease thereby stopping the centrifuge.
In the event that an electrode fails or a cable becomes disconnected, the detector will immediately signal the fact that the detector is not functional because current ceases to flow through resistor or capacitor 44. Thus operator involvement is not required for monitoring whether the detector is functioning. The invention thus provides a system that is continuously self monitoring.
The invention may be embodied in several forms without departing from its spirit or essential characteristics. The scope of the invention is defined in the appended claims, rather than in the specific description preceding them. All embodiments that fall within the meaning and range of equivalency of the claims are therefore intended to be embraced by the claims. | A blood processing assembly includes a centrifuge contained within a heated housing or chamber. A fail safe spill or splash detector is located within the inner wall of the housing. The detector includes a pair of parallel electrodes separated from each other from a small gap. The circuit detects a splash or droplet of liquid which conducts current between the electrodes. | 1 |
FIELD OF THE INVENTION
The present invention relates to a system for providing a secondary means of securing tubular members held together by a friction-lock system. In particular, the present invention relates to a mechanical latch that prevents drilling risers that are held together by friction from separating inadvertently.
BACKGROUND
In offshore drilling operations in deep water, the operator will perform drilling operations through a drilling riser string. The drilling riser string extends from a floating platform, such as a drilling ship, to a subsea wellhead or subsea tree assembly on the seafloor. The drilling riser string is made up of a number of individual riser joints or sections that are secured together to form the drilling riser string. The drilling riser string forms a central tube for passing a drill pipe from the floating platform to the wellhead on the sea floor. The drilling riser string normally has a number of auxiliary conduits that extend around the central tube. The auxiliary conduits may serve several purposes, such as supplying hydraulic fluid pressure to the subsea blowout preventer and lower marine riser package.
Typically, the central tube of a drilling riser joint has a pin member on one end and a box member on the other end. The pin end of one riser joint stabs into the box end of the adjoining riser joint. In one type of riser joint, flanges extend outward from the pin and box. The operator connects the flanges together with bolts spaced around the circumference of the coupling. In another type of riser, individual segments or locking segments are spaced around the circumference of the box. A screw is connected to each locking segment. Rotating the screw causes the locking segment to advance into engagement with a profile formed on the end of a pin.
In these systems, a riser spider or support on a riser deploying floor moves between a retracted position into an engaged position to support previously made-up riser joints while the new riser joint is being stabbed into engagement with the string. Wave movement can cause the vessel to be moving upward and downward relative to the riser when the riser is in operation.
In both types of risers, workers use wrenches to make up the bolts or screws. Personnel employed to secure the screws or the bolts are exposed to a risk of injury. Also, the process of making up the individual bolts is time consuming. Often when moving the drilling rig from one location to another, the riser has to be pulled and stored. In very deep water, pulling and rerunning the riser is very expensive.
A technique has been developed that uses a cam ring and dogs to secure drilling riser joints together. Each riser joint has a box end and a pin end. The pin end of one drilling riser joint is disposed within the box end of an adjoining drilling riser joint. The box ends of each drilling riser joint have dogs that are driven into engagement with the pin ends of the adjoining drilling riser joints by moving the cam ring axially. Friction between the dogs and the cam ring maintains the cam ring positioned to drive the dogs against the pin end of the adjoining drilling riser joint. No bolts or screws are used to connect drilling riser joints using this technique.
However, it is conceivable that friction may not be sufficient to maintain the cam rings at their desired axial positions so that the cam rings drive the dogs against the pin ends of the adjoining drilling riser joints. Were a cam ring to move from its desired axial position, its dogs could back out from the pin end of the adjoining drilling riser joint. If that were to occur, the drilling riser joints may disconnect from each other.
Therefore, a more effective technique is needed to secure drilling riser joints together. In particular, a technique is desired that would enable adjoining drilling riserjoints to be connected quickly and remain connected during operation.
BRIEF DESCRIPTION
A technique for securing drilling riser joints in a drilling riser string is presented. The drilling riser joints have a tubular housing that has a box configuration on one end and a pin configuration on the other end. The drilling riser string is assembled by connecting the pin end of one drilling riser joint to the box end of an adjoining drilling riser joint. A moveable ring is used to connect adjoining drilling riser joints. The moveable ring is used to drive a fastener, such as a dog, of one drilling riser joint against the adjoining drilling riser joint. The moveable ring is driven axially from a first position, where the fastener is not engaged against the adjoining drilling riser joint, to a second position, where the fastener is engaged against the adjoining drilling riser joint.
The technique also comprises the use of a latch to prevent the moveable ring from moving inadvertently from the second position. This prevents the drilling riser joints from disconnecting inadvertently. In the embodiment described below, the latch has a cantilevered arm having a toothed profile. The moveable ring also has a toothed profile that corresponds with the toothed profile on the latch. When the moveable ring is in the second position, the toothed profile on the latch engages the toothed profile on the moveable ring. The engagement of the toothed profile on the latch with the toothed profile on the moveable ring obstructs axial movement of the moveable ring. To disconnect the drilling riser joints, a tool is used to provide sufficient force to overcome the engagement of the toothed profiles on the latch and the moveable ring.
DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
FIG. 1 is a schematic view of a drilling riser system, in accordance with an exemplary embodiment of the present technique;
FIG. 2 is an elevation view of a portion of the drilling riser system of FIG. 1 , in accordance with an exemplary embodiment of the present technique;
FIG. 3 is a cross-sectional view of the portion of the drilling riser system of FIG. 2 , in accordance with an exemplary embodiment of the present technique;
FIGS. 4-6 are a side elevation view, a front elevation view, and a perspective view of the secondary latch for a riser joint connection, in accordance with an exemplary embodiment of the present technique;
FIG. 7 is an elevation view of the first drilling riser joint and second drilling riser joint with a cam ring used to secure the first drilling joint to the second drilling riser joint in a first axial position, in accordance with an exemplary embodiment of the present technique;
FIG. 8 is an elevation view of the first drilling riser joint and second drilling riser joint with a cam ring used to secure the first drilling joint to the second drilling riser joint in a second axial position, in accordance with an exemplary embodiment of the present technique
FIG. 9 is a partial cross-sectional view of a drilling riser joint and a system for connecting drilling riser joints together, in accordance with an exemplary embodiment of the present technique;
FIG. 10 is a partial cross-sectional view of a pair of drilling riser joints joined together by the system for connecting drilling riser joints together, in accordance with an exemplary embodiment of the present technique; and
FIGS. 11-13 are a sequence of elevation views illustrating the use of retractable jaws to connect a first drilling riser joint to a second drilling riser joint, in accordance with an exemplary embodiment of the present technique.
FIG. 14 is a top cross-sectional view of a riser joint connection, in accordance with an exemplary embodiment of the present technique;
DETAILED DESCRIPTION
Referring now to FIG. 1 , the present invention will be described as it might be applied in conjunction with an exemplary technique, in this case, a drilling riser string 20 to enable a subsea well to be drilled from a floating platform 22 . The drilling riser string 20 is secured to a lower marine riser package and Blowout Preventer (BOP) stack 24 , which is, in turn, secured to a subsea wellhead or subsea tree 26 of the well. The drilling riser string 20 is supported in tension by riser tensioners 28 suspended from the floating platform 22 .
The drilling riser string 20 is comprised of a series of riser joints 30 that are connected together to form several tubes that extend from the floating platform 22 to the lower marine riser package 24 . The drilling riser string 20 enables drill pipe 32 to be deployed from the floating platform 22 to the lower marine riser package 24 and on through the wellhead 26 into the seabed through a central tube 34 formed by the riser joints 30 . Drilling mud may be provided from the floating platform 22 through the drill pipe 32 and back to the floating platform 22 in the annulus between the drill pipe 32 and the inner walls of the central tube 34 . Auxiliary tubes 36 formed by the riser string 20 may be used for other purposes, such as serving as choke-and-kill lines for re-circulating drilling mud below a blowout preventer (BOP) in the event that the BOP secures flow through the central tube 34 .
Referring generally to FIGS. 2 and 3 , each riser joint 30 has a box end 38 and a pin end 40 that are used to connect each riser joint 30 to another riser joint 30 . As shown here, the box end 38 of a first riser joint 42 is connected to the pin end 40 of a second riser joint 44 . In this embodiment, the first riser joint 42 is oriented in a box-up orientation and the second riser joint 44 is oriented in a pin-down orientation. However, the first and second riser joints 42 , 44 may be oriented in the opposite orientation: pin-up/box-down. Here, the pin end 40 of the second riser joint 44 is stabbed into the box end 38 of the first riser joint 42 . As will be discussed in more detail below, a tool is used to drive a cam ring 46 of the box end 38 of the first riser joint 42 downward from a first axial position to a second axial position to connect the second riser joint 44 to the first riser joint 42 . The downward axial movement of the cam ring 46 urges a series of dogs (not shown in this view) disposed on the box end 38 of the first riser joint 42 inward against the pin end 40 of the second riser joint 44 . The engagement of the dogs secures the second riser joint 44 to the first riser joint 42 . To disconnect the first riser joint 42 and second riser joint 44 , the cam ring 46 is lifted to release the dogs from engagement with the pin end 40 of the second riser joint 44 .
In the illustrated embodiment, a latch 48 is provided to lock the cam ring 46 in the second axial position to maintain the second riser joint 44 connection to the first riser joint 42 . The cam ring 46 is held in the second axial position by friction between the cam ring 46 and the dogs. However, the latch 48 provides an additional mechanism by which the cam ring 46 is prevented from being moved inadvertently from the second axial position to the first axial position. As will be discussed in more detail below, the latch 48 is mounted on the box end 38 of each riser joint 30 and engages the cam ring 46 when the cam ring 46 is driven downward to the second position. The engagement between the latch 48 and the cam ring 46 resists upward movement of the cam ring 46 . Thus, the latch 48 maintains the second riser joint 44 connected to the first riser joint 42 .
Referring generally to FIGS. 4-6 , the latch 48 is adapted to cooperate with the cam ring 46 to prevent inadvertent axial movement of the cam ring 46 . The illustrated embodiment of the latch 48 has a toothed profile 50 that is located on one end of a cantilever arm 52 . The toothed profile 50 is configured to engage a corresponding grooved portion of the cam ring 46 when the cam ring 46 is positioned in the second axial position. Upward movement of the cam ring 46 from the second axial position to the first axial position is opposed by the engagement between the toothed profile 50 of the latch 48 and the corresponding grooved portion of the cam ring 46 . The cantilever arm 52 biases the latch 48 outward so that the toothed profile 50 will engage the corresponding grooved profile of the cam ring 46 . However, as will be discussed in more detail below, the cantilever arm 52 also enables the toothed profile 50 to be flexed inward during intentional axial movement of the cam ring 46 so that the toothed profile 50 of the latch 48 ratchets along the corresponding grooved portion of the cam ring 46 . In addition, the illustrated embodiment of the latch 48 has a pair of mounting holes 54 for securing the latch 48 to the box end 38 of each riser joint 30 . However, other arrangements and methods for securing the latch 48 to the riser joint 30 may be used.
Referring generally to FIG. 7 , the cam ring 46 is presented in the first axial position on the box end 38 of the first riser joint 42 . The cam ring 46 has a toothed profile 56 that is adapted to engage the toothed profile 50 of the latch 48 . In this embodiment, the toothed profile 56 extends around the inner circumference of the cam ring 46 . The toothed profile 50 of the latch 48 does not engage the toothed profile 56 of the cam ring 46 when the cam ring 46 is in the first axial position. Instead, the toothed profiles 50 , 56 are configured so that they are engaged only when the cam ring 46 is at or near the second axial position. The box end 38 has a cavity 58 that is provided to receive the latch 48 as the latch 48 ratchets when the cam ring 46 is moved axially.
Referring generally to FIG. 8 , the cam ring 46 is presented in the second axial position on the box end 38 of the first riser joint 42 . When the cam ring 46 is driven downward, as represented by arrow 60 , dogs (not shown) of the box end 38 of the first riser joint 42 are driven into an outer profile 62 of the pin end 40 of the second riser joint 44 . The cantilever arm 52 of the latch 48 is biased outward from the cavity 58 to engage the toothed profile 50 of the latch 48 with the toothed profile 56 of the cam ring 46 .
Referring generally to FIGS. 9 and 10 , a tool 64 is used to connect the riser joints 30 to form the riser string 20 . In the illustrated embodiment, the tool 64 has a plurality of retractable braces 66 that are extended outward to support a flange 68 of the first riser joint 42 . The braces 66 also align the first riser joint 42 for connection with the second riser joint 44 . The braces 66 are retracted to enable the first and second riser joints 42 , 44 to pass through the tool 64 during assembly and disassembly of the riser string 20 .
The tool 64 is adapted to connect the riser joints 30 in a box-up/pin-down configuration. The first riser joint 42 is supported in the tool 64 with the box end 38 upward in this embodiment. Consequently, the pin end 40 of the second riser joint 44 is inserted into the box end 38 of the first riser joint 42 . The box end 38 of the first riser joint 42 has a plurality of dogs 70 that are used to connect the box end 38 of the first riser joint 42 to the pin end 40 of the second riser joint 44 are presented. The dogs 70 extend through windows 72 in the box end 38 . As the cam ring 46 is driven downward to the second axial position, as represented by arrow 76 , the dogs 70 are driven by the cam ring 46 inward, as represented by arrow 78 , into engagement with the outer profile 62 of the pin end 40 of the second riser joint 44 . The tool 64 has a plurality of retractable jaws 74 that are extended outward to engage the cam ring 46 and drive it axially downward or upward.
Referring generally to FIGS. 11-13 , the jaws 74 are adapted to drive the cam ring 46 downward, as represented by arrow 76 , to drive the dogs 70 of the first riser joint 42 inward, as represented by arrow 78 , against the outer profile 62 of the pin end 40 of the second riser joint 44 . In addition to the latches 48 , friction between the inner surface 80 of the cam ring 46 and the outer surface 82 of the dogs 70 maintain the cam ring 46 in the second position.
Referring generally to FIG. 14 , the illustrated embodiment of the box end 38 of a riser joint 30 utilizes three latches 48 that are disposed equidistant around the central tube 34 to maintain the cam ring 46 in the second axial position. However, a greater or lesser number of latches 48 may be used. As noted above, when the cam ring 46 is in the second axial position, the cam ring 46 drives dogs 70 against the pin end 40 of the upper riser 44 through windows 72 in the box end 38 of the lower riser 42 , connecting the second riser joint 44 to the first riser joint 42 .
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | A technique for securing drilling riser joints in a drilling riser string is presented. The drilling riser joints have a tubular housing that has a box configuration on one end and a pin configuration on the other end. The drilling riser string is assembled by connecting the pin end of one drilling riser joint to the box end of an adjoining drilling riser joint. A moveable ring is used to connect adjoining drilling riser joints. The moveable ring is used to drive a fastener of one drilling riser joint against the adjoining drilling riser joint. The moveable ring is driven axially from a position where the fastener is not engaged against the adjoining drilling riser joint to a position where the fastener is engaged against the adjoining drilling riser joint. A latch is used to prevent the moveable ring from moving inadvertently from the second position. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a system for distributed data storage that ensures the safety of the user data. In particular, the system of the present invention provides that the data stored in a cloud storage service are encrypted and their cryptographic keys are created from a remote device. In the context of the present invention, cloud is a set of servers that form an online service over the Internet, these servers are invisible to the user of the service pretending they form only a single server, thus forming a “cloud servers”. These keys will be divided and stored in cloud storage part and part on other devices.
BACKGROUND OF THE INVENTION
[0002] While a mobile device is personal, unexpected situations can occur, such as loss or theft of the same. If this device has any sensitive or confidential information, it might be disclosed or lost.
[0003] To ensure that such information is not lost, it would be necessary some kind of redundancy, for example, to keep a copy on a local hard drive and the other in a remote location accessible over the Internet. However, storing sensitive data in online servers also poses risks, such as the invasion and/or information theft.
[0004] Within this context, to increase the degree of information security, this data should be encrypted, both in online copy or in remote device. Thus, even in case of theft or intrusion device of the server, the information itself will not be stolen.
[0005] Several security issues are found in the prior art, as detailed below:
Problem 1
[0006] One company had a leak portfolio with incalculable loss because one of the employees consulted some company documents on their mobile device, but that device was stolen while he was at a bar or other public place.
Problem 2
[0007] The employee of a company using the Wi-Fi network provided by the hotel where he was staying, carries sensitive data that are in online storage. But he paid no attention to the Wi-Fi did not have any kind of encryption. An attacker capturing the packets that travel in the middle of Wi-Fi network can view the data traffic, obtaining thus the information.
Problem 3
[0008] Files of a company are exclusively stored in an online service that offers no data encryption. In this case, a group of hackers attacking this service over the Internet is very likely that the company's portfolio is stolen. To minimize the risk of problems of the examples presented above, it is possible to adopt the following improvements for each of these cases, respectively:
Improvement for Problem 1: to use virtual storage (cloud); Improvement for Problem 2: to use a data connection encrypted (HTTPS for example); Improvement for Problem 3: encrypted storage in the cloud and on the phone;
[0012] However, these improvements do not provide a complete solution. Even with the addition of cryptographic techniques in the system other problems still need to be covered, as described below:
Problem 4
[0013] A system of online storage with encryption is deployed. In this type of system, controlling of data access is done by means of cryptographic keys. However, as this system uses keys that expire, each time a key expires, the entire file system should be re-encrypted, which, in turn, implies in great data traffic for all users because data stored on devices from other users will be invalid, requiring reloading the data stored in the cloud.
Problem 5
[0014] A company hires a group of hackers to steal information from another particular company. This group is one of the employees who have permission to take the documents home. The group, knowing that the mobile device that contains employee information they seek, steals your device. Although sensitive data is encrypted inside the device, hackers knowing the encryption key is stored within it, through a brute force attack on the hard drive of the phone can decrypt the data, thus achieving extract the desired information.
[0015] To overcome the above problems, some known solutions can be provided as follows:
Improvement for problem 4: each user has his account, with no need for directory access control, reducing the data traffic. Improvement for Problem 5: Division of keys between online storage and device
[0018] The patent document US2010235630 A1, published on May 20, 2010, holder UNISYS CORPORATION, describes a method and system for protecting data in a data storage network. The method comprises receiving data in a safe place for their respective storage. The method includes dividing the data received by means of cryptographically secure storage blocks in a variety of secondary data, and dividing cryptographic key to access data in a variety of key fragments. The method further includes encrypting each of the variety of data blocks with different keys, implementing a cloud that manages to retain a single IP for its infrastructure and using a secure bridge for communication between client and servers, preventing someone who is capturing the transmission has access to data transmitted. However, the storage protection still has flaws, and can be exploited.
[0019] The patent document WO2010057194 published on Sep. 16, 2010, holder: NOVELL, INC., describes a system to provide cloud computing services. This system comprises a cloud computing environment with resources for the data to be managed in the cloud, each load data having an address to the same cloud. Said system works so that a given data load to obtain a key from a first cryptographic key pair, said pair of keys for decrypting encrypted hosted storage within the cloud computing environment. The main purpose of this document is to increase the protection of the data stored in the cloud, using keys to this section by hard drive and dividing the file across multiple disks differently, complicating thus the theft of information in case of theft of the storage disk or theft of one of the keys, however, it is still extremely vulnerable to information theft on the client.
[0020] The document CN 201408416 published on Feb. 17, 2010, holder: TSINGHUA TONGFANG CO LTD, describes a mobile storage device with a storage mechanism and division keys. The device comprises an interface unit, a processing and control unit, a cryptographic service unit and a data storage unit. A decryption key used by the storage device is formed by the union of two or more segments of data or generated by an algorithm corresponding to this. Each segment has different forms of data storage and access mechanisms. The device is thus of broad protection provided by the adoption of the division of keys and storage mechanism, causing the device to be highly secure. This document relates to mobile storage devices that store the encrypted data and encryption key in separate pieces, spreading to the storage, hence impeding the theft. But the key is still in the entire device.
[0021] The document Wuala BY LACIE available on http://www.wuala.com/ is a commercial system that provides encrypted storage leaving the data encrypted on the client side (device). For this system has focused on several different users using the same cloud, it uses its own encryption and access control. This approach is advantageous for multiple users, but periodically causes the entire file system has to be encrypted and transmitted again consuming a large amount of processing and data transmission. We still have that as a key to decipher the data is still on the mobile device, it may be that an attacker breaks the encryption of stored data.
[0022] In order to overcome the disadvantages of the prior art, the present invention proposes a system focused on the security of data stored in a cloud infrastructure, as well as secure data in transfer, using a secure bridge (HTTPS), that also protects data stored. Furthermore, the system of the present invention uses asymmetric keys stored on the device and in the cloud, to ensure that even in case of theft of the device or hard disks will not be possible to obtain the key, since only with the two together can be calculated the symmetric key and without it you, it is not possible to decipher data. Moreover, since the system is not intended for use by multiple users, this is only one user on different devices, it is not necessary cipher again the file system and retransmit it, thereby minimizing the data exchange.
[0023] To provide the online storage of information, the present invention uses cloud storage service.
SUMMARY OF THE INVENTION
[0024] The system presented suggests that the data stored in the cloud are encrypted and that their encryption keys are created on a device, whether portable, mobile or fixed, and stored in a divided party cloud storage and part of the device itself. Thus, it is possible to ensure that:
If the device is stolen, you cannot decipher the data, and If the cloud storage is hacked, it will also be impossible to decipher the data.
[0027] Furthermore, the present invention proposes that files stored on-line will be divided into pieces (clusters) and that each cluster has its hash value calculated. In the context of the present description, hash (H) is a set of bytes of known small size, which is generated by mathematical operations, from large set of bytes (F) such that there are not two or more different Fs that generate a same H. In this context, comparing the computed hash values with those stored in the cloud, you can see which clusters have been modified. Using this information, we have only the clusters which have been modified will be trafficked, which, in turn, decreases the data transmission on the updated file system. In general, the system works as follows:
[0028] First, the system is booted. If the first run, the system will automatically generate the encryption keys, otherwise the keys that are stored in the cloud should be loaded into the system. Next, the symmetric key to be decrypted. From this key, the system goes to the main menu and is on standby. When a user interaction occurs, it will be checked if it was a written request for the file, otherwise the file is opened in read mode only. If a write request, there are three options: a) removing file, b) adding a new file or c) updating an existing file. After the operation, the system will return to the standby state. When the user wants to exit the system, as nothing was saved in the device, the memory used is released and all keys calculated and downloaded from the cloud will disappear from the device.
[0029] It will be used three pairs of asymmetric keys and a symmetric key by storing a portion of these keys in the cloud will always be necessary that the user is actually logged so that someone can decipher any information. Thus, to be able to decipher the data, it is necessary to have both keys stored on the device, as stored in the cloud storage. With this, the system is more secure because it ensures that even if the storage is compromised or the device is stolen, you cannot decrypt the data stored. This solution is independent of a specific cloud solution, or it can be configured to be used with any existing commercial solution such as, for example, DropBox, Evernotes or Amazon, not limited to those.
[0030] Using the hash of the files, we can transmit only what was changed, thus minimizing data transfer over the network.
[0031] By use a list containing the numbers of clusters for a particular file, it is not necessary that the clusters are sequential, making it more difficult for an attack can break the encryption. This can also lead to clusters that run out of the same file stored in different physical hard drives in the cloud, which increases safety.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The objectives and advantages of the invention will become more apparent from the following detailed description of an exemplary embodiment of the invention and the accompanying drawings, by way of non-limitative example, wherein:
[0033] FIG. 1 gives an overview of the architecture of the secure storage system for distributed data.
[0034] FIG. 2 shows the access to the file system according to the present invention.
[0035] FIG. 3 shows the operation flow of the system according to the present invention.
[0036] FIG. 4 shows the flow of initialization of the system according to the present invention.
[0037] FIG. 5 shows the generation of the cryptographic key system according to the present invention.
[0038] FIG. 6 shows the registration process in the system according to the present invention.
[0039] FIG. 7 shows the flow for opening a file system according to the present invention.
[0040] FIG. 8 shows the stream to modify a file system according to the present invention.
[0041] FIG. 9 shows the flow for adding a file system according to the present invention.
[0042] FIG. 10 shows the flow for deleting a file system according to the present invention.
DESCRIPTION OF THE INVENTION
[0043] The following description is merely exemplary in nature and is not intended to limit the disclosure, application, or use.
[0044] With reference to FIG. 1 , the overall system architecture is shown. To operate the system, first, it is necessary to boot the system. Then, the user 105 may interact with the system ordering it to open, add, modify or remove files from secure storage. For such operations to be performed, the user 105 necessarily need to be using a portable device 110 connected to the internet 120 with access to the cloud 125 , in which the encrypted data is stored on the storage medium 115 of the device and in the cloud 125 . The above storage medium may be any medium suitable for data storage such as a hard drive. All traffic between the device 110 and cloud 125 must be made using some method of secure data traffic, for instance the HTTPS protocol. Thus, the security of transmitted data is guaranteed against possible attacks aimed at capturing data sent.
[0045] FIG. 2 shows a system of files. The file system consists of extension files. “.f”, “.crc”, “.d”, e “.dl”, wherein:
To file with extension “.f”, they represent a file that contains a cluster of 256 KB. This cluster will contain the encrypted file with the standard padding of the prior art. These files can be part of a directory, in which case they will contain a list of files and children directories of the same descriptor. To file with extension “.crc”, they represent the hash code from another file that has the same name, but with different extension. To files with extension “.d”, these contain the descriptor for a particular file. This descriptor contains the first entry to the list of cluster comprising the file, the last modification date and the IP that made the last change. To file with extension “.dl”, they contain a list. Within this list, ten addresses are stored cluster and the continuation of an address list, thereby forming a linked list.
[0050] All files and descriptors have created its set number randomly, thus ensuring that the clusters are not sequential. The descriptor for the root directory will always be the fs0.d, and it contains the necessary information to reach any file. In the example of FIG. 2 , a schematic is presented step by step how a file is stored in the cloud. First, the descriptor is accessed fs0.d containing the list of clusters that forms the root file system (dl645.dl). Deciphering the root directory (fs76.f) gives the name and descriptor of the existing files. To open the file payroll.txt, we accessed the f138.d descriptor that contains the list of cluster comprising that file, and thus deciphered f132.f and f18.f, having access to the content of payroll.txt, which is ready to be used.
[0051] FIG. 3 shows the flow of normal system operation. The first step is to initialize the system 305 . After initialization, the symmetric key KS is in memory. After the system is waiting for some user interaction 310 . When the user interacts with the system by asking some operation in some file, it is checked whether it was a write operation 315 . If not, the file is opened 320 . Otherwise, it is necessary to check which type of write operation was required. If it is a removal 325 , the file is removed from the device and cloud 330 . Otherwise, the requested operation is a modification, and therefore if the operation is in a new file 335 , it should be added to the secure storage 340 . Otherwise, the file must be modified both in the device and in the cloud 345 .
[0052] As shown in FIG. 4 , the flow initialization consists of verifying whether a user and their respective keys were created 405 . If not, a new user should be created 410 . If there is a user, it should log into his account 425 .
[0053] FIG. 5 shows the process of generating cryptographic keys in the first access. More specifically, FIG. 5 details the initialization when the first access of a new user, wherein a set of cryptographic keys to be generated 415 . Said set of keys consists of three pairs of asymmetric keys K 1 , K 1 ′, K 2 , K 2 ′, KM, KM′ and a symmetric key KS, and KM′ (KM (x))=x. According to the present invention, all data is encrypted with the storage key KS, wherein the symmetric key KS is encrypted using the asymmetric key KM. The asymmetric key KM′ will be divided into two pieces and KM′ 1 KM′ 2 . The piece of the asymmetric key KM′ 1 will be ciphered with the key K 1 and will store it on the device. The piece of the asymmetric key KM′ 2 is ciphered with the key K 2 ′ and will store it in the cloud. The keys K 1 and K 2 will be kept on the device and keys K 1 ′ and K 2 ′ in the cloud ( 420 ), as shown in FIG. 5 , thus ensuring that only someone that will have access to KM (KS) will have keys K 1 , K 1 ′ and K 2 , K 2 ′ and is connected with the service, or authenticated.
[0054] According to a preferred embodiment of the invention, a copy of the keys K 1 , K 2 , K 1 ′, K 2 ′, KM (KS), K 1 (KM′ 1 ) and K 2 ′(KM′ 2 ) should be stored in removable memory device (SD Card) and a warning to the user to save on a computer or on a flash drive that has different access the cloud should be issued.
[0055] The registration process in the system illustrated in FIG. 6 . First, the user must have their credentials checked by the provider of online storage. Then it will download the key K 1 ′. Having K 1 (KM′ 1 ) in memory, calculate K 1 ″(K 1 (KM′ 1 )) that results in KM′ 1 . The next step is to download K 2 ′(KM′ 2 ) of online storage. Having key K 2 in memory, it calculate K 2 (K 2 ′(KM′ 2 )) that results in KM′ 2 . With this, we can calculate KM′. With KM ′, we can calculate KM′ (KM (KS)), resulting in symmetric key KS.
[0056] Once the user is registered, the system will check the file system changes. The hash clusters that comprise the file system must be loaded from the cloud 430 , these hashes are used to verify that the copy is equal to the cloud and the device 435 . If different packets of different file system 440 are downloaded and validated, then the file system is mounted ( 445 ).
[0057] FIG. 7 shows the flow for opening a file. First, it is checked if the file is updated with the file from the cloud 705 . If not, the different packages are downloaded 710 , and the file is decrypted using the key KS 715 . The file is decrypted in memory and it is possible to manipulate it or move it out of the safe area 720 .
[0058] FIG. 8 shows the flow for modifying a file. First, the file should be encrypted 805 . Then it must be divided into clusters and 810 clusters should have their hashes calculated. The file system must be further upgraded 815 . For upgrading the cloud, it should be compared the hash codes of modified clusters. For this, we make sure that all clusters have undergone operations that were verified with cloud 820 ; otherwise, it is necessary to check if the next cluster was modified, whether it is new or if it does not exist 825 . If so, the version should be updated in the cloud 830 . It should be remembered that this process serves both as the file to the file system.
[0059] FIG. 9 details the flow to add a file. The file should be encrypted first 905 , and then it should be broken into clusters 910 . Clusters should have their hash codes calculated, and then the file should be added to the file system 915 . This addition implies a modification in the files of the file system. For this, we make sure that all clusters have undergone operations that were verified with cloud 920 . If not, it should be checked whether the next cluster file system has been modified or if it is new ( 925 ). If so, the version of the cluster in the cloud must be updated 930 . When all clusters that represent the file system is checked, the new file will be copied to the cloud 935 .
[0060] FIG. 10 shows the flow to remove a file system. First, the file must have all pieces and hash codes erased 1005 . Next, the file system must be upgraded 1010 . This modification files in the file system implies an update in the cloud. For this, we make sure that all clusters have undergone operations that were verified with the cloud 1015 . If not, you need to check if the next cluster file system has been modified or removed 1020 . If so, the version should be updated in the cloud 1025 . When all clusters that represent the file system is checked, the clusters that represent the file from the cloud will be removed 1030 .
[0061] Although a preferred embodiment of the present invention is shown and described, those skilled in the art will understand that various modifications may be made without departing from the scope and spirit of the invention as defined in the appended claims.
[0062] It is also expressly stated that all combinations of elements which perform the same function in substantially the same way to achieve the same results are within the scope of the invention. | The present invention relates to a system for distributed data storage that ensures the safety of the user data. In particular, the system of the present invention provides that the data stored in a cloud storage service are encrypted and their cryptographic keys are created from a remote device. In the context of the present invention, cloud is a set of servers that form an online service over the Internet, these servers are invisible to the user of the service pretending they form only a single server, thus forming a “cloud servers”. These keys will be divided and stored in cloud storage part and part on other devices. | 7 |
[0001] The present invention is directed to improvements in existing safety-readiness certification programs. Specifically, the programs include the use of a safety advisory board and the use of entry scan systems to ensure worker compliance with safety testing.
BACKGROUND
[0002] Workplace safety is a significant priority for all manufacturing facilities. Safety training and other workplace readiness testing are a part of all responsible facilities. Such training and testing have been instituted for many years and have been successful particularly in connection with stationary work forces.
[0003] In more recent times, the work force has become more flexible and mobile. In the example of the construction industry, different teams of specialized workers may work at multiple sites over multiple days. There is no longer the stationary or relatively stationary work assignment. This means that workers may be subjected to different sites having potentially different safety hazards. It also means that employers see different workers/employees on their sites and have no knowledge of the work safety readiness of those workers.
[0004] Work safety readiness is typically ensured by the sponsor of a worker or a group of workers/employees. The sponsors may include contractors and labor unions for various work specialties including electrical, plumbing, welding, etc. The sponsors will typically provide some training, including safety training, for their workers/employees, but that training often is not organized or systematic. As a work force turns over, there is difficultly in knowing the amount of training of each of the workers. With respect to some safety issues such as drug testing, some workers may try to cheat the system so as to avoid readiness testing. At other times, workers may be inadvertently untrained for various job safety issues.
[0005] One solution to safety training is a certification program. One example is an online verification system for ensuring a worker's safety readiness. The system documents, tracks, and immediately validates (or does not validate) a worker's safe work readiness status. The particular work safety readiness and certification may be defined by the sponsor. Access to the work readiness status may be available wherever there is an internet connection. The system also has different “views” to the system so that workers, sponsors, and employers, for instance, may all have different levels of access to the information.
SUMMARY
[0006] Accordingly, it is an object of the present invention to improve existing verification systems and to improve the quality of safety education and discussion. Further, it is desirable to improve worker tracking with respect to safety.
[0007] In one example, a method for ensuring employees safe work readiness comprises the step of providing a computer processing hub adapted to store information regarding an employee in a hub database. The method further includes providing an advisory board of a plurality of members comprising safety-involved professionals, the advisory board having access to the computer processing hub. The method further includes providing a plurality of safety-related instructional courses reviewed by the advisory board and administering a safety related instructional course to an employee. Further the method includes verifying the identity of an employee and administering a test related to safety-related subject matter to the employee and evaluating the test results to determine a score for the employee's test answers, and storing the test results in the processing hub database making the test results available to an employer that is evaluating the employee's safe work readiness. Still further, the method includes making the employee's test results available to the employee and allowing the employee to ask questions to the advisory board regarding the safety-related subject matter, whereby an employer and employee may use the computer processing hub as an informational resource in the field of safe work readiness. The computer processing hub may comprise a plurality of categories of viewing access. The computer processing hub may be a website server, and the information stored in the hub database may be available on an internet website. The method may further include, after an employee has obtained at least a predetermined score on a predetermined number of tests, certifying the safe work readiness of the employee. Still further, different employers may select different scores on the predetermined test before declaring safe work readiness of an employee or they may require different predetermined tests before declaring safe work readiness of the employee.
[0008] In another example, a method for ensuring employees safe work readiness at an employer job site comprises the steps of providing a computer processing hub adapted to store information regarding an employee in a hub database. The method further includes providing a plurality of safety-related instructional courses and administering a safety-related instructional course to an employee. The method also includes verifying the identity of an employee and administering a test related to the safety-related subject matter to the employee and evaluating the test results to determine the score of the employee's test answers, and storing the test results in the hub database. An employee is provided with an identification card that is adapted to be scanned. The method further includes providing an entry scan system at an employer's job site, the scanned system adapted to read the employee's identification card, and using the entry scan system, confirming that each employee at the employer job site is safe work ready.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a flow chart illustrating the flow of information and inquiries into and out of a computer processing hub in accordance with an example described herein.
[0010] FIG. 2 is a flow chart showing an example of administering a safety-related instructional course and a corresponding test related to the course.
[0011] FIG. 3 is a flow chart showing an example of the operation of an entry scan system that ensures safe work readiness.
[0012] FIG. 4 is a flow chart showing an example of components and their interaction in a computer processing hub.
DETAILED DESCRIPTION
[0013] The present invention is directed to significant improvements over existing, safety-readiness certification systems. The present system includes a computer processing hub that is adapted to store information regarding an employee/worker in a hub data base. (The terms “employee” and “worker” are used interchangeably herein). An advisory board of one or more members involved in the field of safety are assembled. This advisory board has access to the computer processing hub. One or more safety-related instructional courses are reviewed by the advisory board. These courses are administered to relevant workers. After the courses have been taken by the workers, the workers are given a test that relates to the safety-related subject matter of the course. The test results are evaluated to determine a score for the employee's test answers, and those test results are stored in the computer processing hub database. Those test results then become available to an employer that is evaluating an employee's safe work readiness. The employees as well as the employers are allowed to ask questions to the advisory board regarding safety-related subject matter. In this way, the subject matter of the safety courses and related test results may be improved and enhanced. The advisory board becomes a resource not only to the testing authority, for instance a sponsor or employer, but also to the employees themselves. FIG. 1 illustrates the flow of information in an example described herein.
[0014] A computer processing hub acts as a storage device for storing hub database information including information about various workers/employees. The computer processing hub is further connected via a wide area network such as the internet to other computers in order to make the database information available to interested and authorized parties.
[0015] FIG. 4 illustrates an example of the component parts of a computer processing hub. There may be separate database and application servers to enhance operation of the system. The “Safe2Work” database refers to a safety training certification and online verification program. Redundancy is built into the system to protect and preserve the information and the operation of the system. Security components such as a securemail server, firewalls, load balances, SSL appliances, and a traffic prioritizer all protect the operation and confidentiality of the system and the system efficiency.
[0016] The safety-related instructional courses and testing may take place at fixed locations. Workers may be given CDs to view courses at their convenience. The courses and testing may alternatively take place online. It is essential that any testing that is based on the courses include verification of the identity of a worker taking a test. Adequate verification systems may include human instructors that confirm identity of a worker taking a test. Other types of security may also be used. The safety related courses and testing may relate to topics such as specific types of work specialties. In one example, available courses and tests (in English and Spanish) are in the following areas: Aerial Lifts, Asbestos Awareness, Cadmium Safety, Confined Space Entry, Electrical Safety, Fall Protection, Fire Safety, Hazcom: Identifying the Dangers, Ladder Safety, Lead Safety, Lockout/Tagout, Personal Protective Equipment, Scaffold Safety, Silica Safety, and Trenching and Shoring. The courses may also relate to drugs and drug testing and to life saving techniques such as CPR. FIG. 2 illustrates the steps of how a course may be taken and tested online.
[0017] Not every worker/employee needs to complete and pass a test for every safety course. It is possible for an employer to identify the specific courses and tests to be completed by particular employees. In other words, different employers may require different predetermined tests be completed and passed before declaring safe work readiness of an employee. Still further, different employers may select different scores be achieved on the predetermined tests before declaring safe work readiness of an employee. The foregoing are merely examples of how the system may be used to ensure safe work readiness in general and for specific job sites.
[0018] A traditional method of administering courses includes providing courses on CDs and the employee then tests online. This will always be available for those that prefer CDs. When the online tests are taken, they are proctored, and thus the results are verifiable and documented. However, courses may be taken online via a simple coding system that can set up easily. Embedded questions are used so that as one moves through the course, if a question is answered incorrectly, the Employee is remediated back to the course section where the information is covered. Then, once the section is reviewed, they are then given the opportunity to answer the question correctly. They must answer the question correctly before they can continue through the course. They can leave the course at anytime and be bookmarked if they care to resume, at a later time, in the same place. When the course is completed a Knowledge Banked status and date will appear and that will designate that the course has been completed but the Employee has not mastered the online test via a Proctor.
[0019] The test scores from the safety-related testing are all stored in the hub data base. The hub database is a central clearing house made accessible by employees/workers, sponsors, and employers. Others may also have access. In a preferred example, these different classes of individuals will have different levels of access to the information. In this way, the security and confidentiality of the testing is preserved.
[0020] In one example of the present invention, the system of safety-readiness certification includes a mechanism for real-time identification and safety certification. In this alternative, a worker/employee is issued a unique identification card. The card may include a magnetic strip, bar code, or other means for specifically and uniquely identifying the worker. These identification aspects may include a picture or other tamper-resistant features. When a worker appears at a work site, the identification card or other identification means is scanned. The scanning device is connected in real time to the computer processing hub and hub database information regarding safety readiness. FIG. 3 illustrates the steps of this safety-readiness certification process. The worker is immediately checked for safe work readiness. The log-in system also identifies in real time the worker/employee's location. In this way, employee tracking is enhanced by further being able to confirm the safe-work readiness of that worker.
[0021] Program reciprocity within sponsor's member employers allows for the ‘shared’ cost of training employees by not having to constantly re-train them, despite employees' mobility. Work readiness statuses follow employees from employer to employer and from jobsite to jobsite. Work status validation and verification is from wherever there is Internet access, by authorized User Login ID only.
[0022] The safety related advisory board may consist of one up to many members. The members have expertise and are involved in safety related fields. The members may come from different sides of the issue including management, labor, outside consultants, and other fields. The board is an online mechanism to monitor and act on policy and safety issues derived from use of the overall system. A purpose is to minimize issues through group decisions. The board will, for example, have input into the substance of the courses that are presented to the workers. They will have input into the actual testing of those workers. They may have input into the number and quality of tests for given certification. In addition to this input the advisory board would also be available to answer questions from workers, sponsors, employers and others with respect to the safety issues. The board may field questions, alternatively, they could also have routine discussions and topics for discussion that originate with the advisory board members. In one example, the advisory board is connected via the computer processing hub and the internet with outsiders interested in the safety topics. The Advisory Group must be efficient in order to be effective, and it will work to facilitate that end, while providing access to all issues, whether they are handled immediately or placed on the Advisory Group's Agenda for discussion and decision. The Advisory Group, in one example, may be comprised of two Sub-groups:
Policy—Issues concerning implementation of the present system; i.e., vendor issues; Safety—Issues concerning the safety components of the present system;
[0025] i.e., decisions related to the basic safety core curriculum courses.
[0000] The Advisory Group Sub-groups, both Policy and Safety, could meet as a whole. However, the Safety Group could also meet separately to determine safety related issues and will then advise the group as a whole.
[0026] While the invention has been described with reference to specific embodiments thereof, it will be understood that numerous variations, modifications and additional embodiments are possible, and all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the invention. | The present method provides online workforce readiness tracking of pertinent safety status information to safety professionals that is immediate, accurate, documented, verifiable, auditable and easily accessible for all authorized Users. All data is stored online, in one Secure Socket Layer (SSL) database location. The online system provides a ‘real time’ process of safety status validation and verification at multiple User access levels, dependent upon the specific safety information required, in order to determine compliance, as defined by the Owner's work readiness requirements, per Project Site. The present system simplifies and reduces the redundant costs associated with safe work preparedness—specifically, safety training, drug testing, Employee verifications or background checks. | 6 |
TECHNICAL FIELD
This disclosure relates generally to the processes of fabricating various petroleum-based fuels, and more specifically, to hydrogenation processes for obtaining petroleum distillate from light Fischer-Tropsch liquids.
BACKGROUND INFORMATION
Fischer-Tropsch synthesis is known to yield a broad mixture of products including primarily paraffins, and some olefins. The individual compounds of such mixture can contain up to about 200 carbons, the number of carbons between about 20 and about 150, with average number about 60 being typical. Certain quantities of oxygenated products and trace amounts of sulfur- or nitrogen containing products or aromatic compounds can be also present.
Some Fischer-Tropsch processes yield mixtures enriched with C 5 -C 30 alkanes and also containing a significant quantity of olefins and oxygenated compounds such as alcohols or acids. Such mixtures are known as “light Fischer-Tropsch liquids” or “LFTL.” Light Fischer-Tropsch liquids are frequently used as a raw material for obtaining various petrochemical products, such as, e.g., petroleum distillates, or diesel fuels, among others.
To make LFTL useful and suitable as blending stock for diesel fuel, olefins and oxygenated compounds contained therein are removed, typically by the saturation of olefins and by conversion of oxygenated compounds into water via hydrogenation also known as hydrotreating, which involves the processes of hydrogenation of LFTL in the presence of hydrogen and a catalyst.
Despite its many advantages, hydrotreating of LFTL is characterized by a number of drawbacks and deficiencies. For example, the process usually requires using very high pressures and temperatures. In addition, while traditional hydrotreating does allow for removal of olefins and oxygenated compounds, the final product often has a cloud point that is too high, limiting the amount of the product that can be blended into diesel fuels.
To avoid or lessen the effects of the above-mentioned deficiencies, as well as for the purposes of improvement of the overall process efficiency, better processes are needed to be used with light Fischer-Tropsch liquids.
SUMMARY
We provide methods for obtaining a petroleum distillate product. One method comprises subjecting an untreated light Fischer-Tropsch liquid to a first hydrogenation in the presence of a first catalyst to obtain a hydrotreated light Fischer-Tropsch liquid composite and subjecting the hydrotreated light Fischer-Tropsch liquid composite to a second hydrogenation in the presence of a second catalyst to obtain and recover the petroleum distillate product.
The light Fischer-Tropsch liquid subject to hydrogenation may be an untreated light Fischer-Tropsch liquid having the degree of unsaturation characterized by the bromine number of about 200 or below. The light Fischer-Tropsch liquid subject to hydrogenation may be also an untreated light Fischer-Tropsch liquid containing between about 1 mass % and about 20 mass % of oxygen.
The first catalyst, i.e., the catalyst used in the first step of hydrogenation process, may be a metallic composition embedded within an inorganic oxide or a zeolitic substrate, the composition comprising a base metal, e.g., a nickel-molybdenum composition or a cobalt-molybdenum composition. The metallic composition comprising the first catalyst may also include at least one noble metal, such as platinum or palladium.
The second catalyst, i.e., the catalyst used in the first step of hydrogenation process, may be a metallic composition embedded within an inorganic oxide or a zeolitic substrate, the composition comprising a base metal, e.g., a nickel-molybdenum composition or a cobalt-molybdenum composition. The metallic composition comprising the second catalyst may also include at least one noble metal, such as platinum or palladium. The first and the second catalysts may be the same or different.
We also provide a system for obtaining a petroleum distillate that subjects an untreated light Fischer-Tropsch liquid to a first hydrogenation and yields a hydrotreated light Fischer-Tropsch liquid composite, and a second hydrogenating unit that subjects the hydrotreated light Fischer-Tropsch liquid composite to a second hydrogenation and yields the petroleum distillate product.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically a system for hydrogenating of light Fischer-Tropsch liquids according to one embodiment of the present invention.
FIG. 2 illustrates schematically a system for hydrogenating of light Fischer-Tropsch liquids according to another embodiment of the present invention.
DETAILED DESCRIPTION
The following definitions and abbreviations are used below, unless otherwise described:
The term “a light Fischer-Tropsch liquid” or the abbreviation “LFTL” is defined as a mixture comprised of n-paraffins having the number of carbons between about 5 and about 50, the mixture containing a substantial portion of C 5 -C 30 alkanes and also containing olefins and oxygenated compounds.
The term “a hydrocarbon” is defined as an organic compound, the molecule of which consists only of carbon and hydrogen.
The terms “a paraffin” and “alkane” are used interchangeably and refer to a hydrocarbon identified by saturated carbon chains, which can be normal (straight), branched, or cyclic (“cycloparaffin”), and described by a general formula C n H 2n+2 , where n is an integer. Paraffins or alkanes are substantially free of carbon-carbon double bonds (C═C).
The term “an olefin,” also known as “alkene” is defined as a hydrocarbon containing at least one carbon-carbon double bond, and described by a general formula C n H 2n , where n is an integer.
The terms “hydrogenation” and “hydrotreating” are used interchangeably and refer to a process of addition of hydrogen to unsaturated organic compounds, such as olefins (alkenes), typically, in a presence of a suitable catalyst, to obtain saturated organic compounds, such as alkanes, as a result.
The term “a catalyst” is defined as substance that changes the speed or yield of a chemical reaction without being itself substantially consumed or otherwise chemically changed in the process.
The term “a noble metal” refers to a metal that is highly resistant to corrosion or oxidation, and does not easily dissolve, as opposed to most base metals. Examples include, but are not limited to, platinum, palladium, gold, silver, tantalum, or the like.
The team “a base metal” refers to any non-precious metal that is capable of being readily oxidized. Examples include, but are not limited to, nickel, molybdenum, tungsten, cobalt, or the like.
The term “a bromine index” or “bromine number” indicates the degree of aliphatic unsaturation and is defined as the amount of bromine in grams absorbed by 100 grams of a sample containing an unsaturated compound, such as an olefin.
The term “a cloud point” refers to a temperature at which fuel starts congealing and starts becoming cloudy due to the appearance of wax crystals, when the fuel is tested in accordance with the American Society for Testing and Materials (ASTM) Specification D2500. The cloudiness increases as the temperature is lowered further.
The term “diesel fuel” is defined in accordance with the specifications described in the ASTM Specification D975 and refers to a petroleum fraction having containing primarily C 10 -C 24 hydrocarbons and having distillation temperatures of about 160° C. at the 10% recovery point and about 340° C. at the 90% recovery point.
The term “API gravity” refers to American Petroleum Institute's measure of the density of a petroleum product relative to the density of water.
The abbreviation “WABT” means “weighted bed average temperature” and refers to an average temperature on the bed of catalyst.
The abbreviation “LHSV” means “liquid hourly space velocity” and refers to a ratio between the hourly volume of feedstock used in the process of hydrogenation and the volume of catalyst used.
The abbreviations “IBP” and “EBP” refer to the temperatures that are the initial boiling point of a product and the ending boiling point, respectively.
A petroleum distillate product may be obtained by using a two-stage process of hydrogenation. At the first stage, where most of the hydrotreating occurs, an untreated light Fischer-Tropsch liquid may be subjected to hydrogenation, which includes reacting the untreated LFTL with gaseous hydrogen, at an elevated temperature and elevated pressure, in the presence of a catalyst. During hydrogenation, the olefins that are present in the untreated LFTL react with hydrogen and become saturated by forming alkanes. If the original LFTL contained some quantity of cycloolefins, in addition cycloalkanes may be also formed. As a result, a hydrotreated light Fischer-Tropsch liquid composite is formed and water is released as a by-product.
The hydrotreated light Fischer-Tropsch liquid composite obtained as described above is then further hydrogenated to complete the process. Again, the second stage of hydrogenation includes reacting the hydrotreated LFTL, at an elevated temperature and elevated pressure, in the presence of a catalyst. Upon the completion of the process of hydrogenation, the final petroleum distillate product may be recovered. The final product is a diesel range material that may be substantially devoid of olefins and oxygenated products and may be suitable for blending with diesel fuels.
Both stages of hydrogenation may be carried out in a hydrotreating unit, or in two separate hydrogenating units, as desired. The temperature at which hydrogenation is carried out may be between about 200° C. and about 370° C., such as about 315° C. The pressure at which hydrogenation is carried out may be between about 1 MPa and about 15 MPa, for example, about 4 MPa. A desired rate of supply of hydrogen gas can be selected. For example, hydrogen gas can be supplied at a rate between about 170 and about 840 m 3 per 1 m 3 of the untreated LFTL at the first stage of hydrogenation or per 1 m 3 of the hydrotreated LFTL at the second stage.
Each stage of hydrogenation can be carried out under the same conditions, such as temperature, pressure, and the rate of hydrogen supply, or under the different conditions so long as the temperature and pressure are within the respective ranges disclosed above.
The process of hydrogenation can be described by the exemplary reaction schemes (1) (for straight-chained olefins such as methylbutene) and (2) (for cycloolefins such as cyclopentene):
As can be seen from the reaction schemes (1) and (2), the process of hydrogenation is carried out in the presence of a catalyst. An appropriate catalyst can be selected from a variety of available options known in the art. For example, the catalyst that can be used is a base metal composition, such as a nickel-molybdenum composition, a cobalt-molybdenum composition, or the like. Alternatively, or a noble metal composition comprising, for example, platinum, palladium, or the like can be employed. The same catalyst or different catalysts can be utilized at the first and second stages of hydrogenation as discussed above.
Hydrotreating is frequently a catch-all term for numerous processes that entail treating products with hydrogen. Hydrotreating includes processes such as hydrodeoxygenation, hydroisomerization, hydrocracking, and hydrodewaxing to name a few. To one skilled in the art, it is generally apparent which particular hydrotreating process is being employed when one is studying the fluids being treated, and the resulting products, as well as operating conditions. The preferred process is briefly described in order to clarify specific hydrotreating steps in the process of producing a high grade blending stock from Fischer-Tropsch liquids.
In a preferred process, the present invention uses a two step hydrotreating procedure. The first step involves hydrotreating the LFTL over a first catalyst for the purpose of hydrodeoxygenation and partial saturation of unsaturated hydrocarbon compounds. The first catalyst is an amorphous catalyst having a metal embedded therein. The removal of oxygen from the LFTL provides protection for catalysts used in the further processing of the hydrotreated LFTL. The hydrotreated LFTL is further processed over a second catalyst for isomerization and some cracking of the hydrocarbon compounds within the hydrotreated LFTL. The second catalyst is a zeolite having a metal embedded therein. The second step comprising isomerization and some cracking improves the pour and cloud points of the liquid allowing for blending into a diesel pool or, depending on the desired degree of cracking, can produce a high quality jet fuel.
In a normal process for multistage hydrotreating of a Fischer-Tropsch liquid, the process entails hydrotreating the Fischer-Tropsch liquid over an amorphous catalyst with the primary purpose of oxygen removal from the liquid. The second step of hydroisomerization is also performed with an amorphous catalyst to provide an isomerized and deoxygenated Fischer-Tropsch liquid. This can be seen in U.S. Pat. No. 6,602,402, where the process of Benazzi et al. use amorphous catalysts for the first hydrotreating step, and the hydroisomerization step. Benazzi et al. further requires an additional step for dewaxing the hydrotreated and hydroisomerized Fischer-Tropsch liquid. The present invention does not have a hydrodewaxing step as in Benazzi et al., but overcomes drawbacks to Benazzi's second step of hydroisomerization by using a zeolitic catalyst for generating a blending stock and eliminating Benazzi's third step of dewaxing as this is accomplished in our second reactor.
Any LFTL can be used as feedstock as the starting product in the hydrogenation processes described above, including a variety of commercially available light Fischer-Tropsch liquids. The starting untreated LFTL may have distillation temperatures of about 90° C. at the 10% recovery point and about 370° C. at the 90% recovery point.
An acceptable LFTL that can be used may include a substantial quantity of paraffins, which may include one or more straight-chained paraffin(s) and may in addition include at least one branched paraffin. Such straight-chained and branched paraffin(s) are the principal components of the untreated starting LFTL. In addition to straight-chained paraffin and branched paraffin(s) the paraffin composition can further comprise at least some quantity of cycloparaffin(s).
Furthermore, the starting LFTL may have the contents of olefins that is characterized by the bromine number greater than about 10. In addition, the starting LFTL may include a quantity of oxygenated products that is characterized by the total oxygen contents between about 1 mass % and about 20 mass %. Not more than just trace amounts of any aromatic compounds, including alkyl aromatic compounds and polyalkyl aromatic compounds, may be present in the original LFTL.
The final product of the entire process of hydrogenation can be for blended with diesel fuels and with jet oil, may have the cetane number of at least about 50, and may have a cloud point of about 5° C. or less.
Various systems and apparatuses can be used for conducting our processes. One embodiment of such a system that can be used is shown by FIG. 1 and can be described as follows. FIG. 1 illustrates the system 100 comprising three hydrotreatment reactors 4 , 11 , and 19 . All three reactors may be the same or different. In the exemplary system 100 shown by FIG. 1 , the reactors 4 and 11 may use a nickel/molybdenum catalysts such as KF-647 or KF-846, and the reactor 19 may utilize a platinum/palladium catalyst. The catalysts are described in more detail in the “Examples” portion of the application, below.
The LFTL feed 1 can be mixed with the hydrogen gas 2 that can be supplied at a rate between about 170 and about 840 m 3 per 1 m 3 of the LFTL. The LFTL/H 2 mixture can be then pre-heated to the desired temperature (e.g., 200° C. and about 370° C., such as about 315° C.) and can be then directed to the first hydrotreatment reactor 4 . The process of hydrogenation then occurs inside the reactor 4 and includes the reaction of the LFTL with hydrogen gas on a bed, such as a fixed bed, of a catalyst (not shown). As hydrogen is consumed during this process, hydrogen may be replenished from a make-up source of hydrogen 3 , and hydrogen provided from this source may contain some amount of H 2 S. The process may be carried out at a pressure between about 1 MPa and about 15 MPa, for example, about 4 MPa. The required pressure can be generated and maintained using the compressor 7 .
The exothermic reactions occurring in reactor 4 may lead to a temperature increase. In order to control the temperature in the reactor the reacting fluid may be cooled (quenched). Such quenching can be achieved by supplying cool hydrogen via the by-pass line 5 . Upon completion of this stage of hydrogenation, the partially hydrogenated product then may exit the reactor 4 and be directed into the separator 6 , where water is separated as the stream 13 . The product may exit the separator 6 via the line 8 , and may then be directed to the second hydrotreatment reactor 11 , using the pump 9 .
In the second reactor 11 , the process of hydrogenation may be continued using additional hydrogen that may be supplied via the line 10 . The conditions for the second stage hydrogenation may be the same as those used for the hydrogenation in the reactor 4 , as described above.
The hydrogenated product then may exit the reactor 11 and be directed into the separator 12 , where water is separated as the stream 13 , and the product may exit the separator 12 via the line 14 , and may then be directed to the stripper 15 , where the H 2 S gas is removed as the stream 16 , and the product may exit the stripper 15 via the line 17 , and may then be directed to the third hydrotreatment reactor 19 , using the pump 18 .
The final stage of the process of hydrogenation then occurs inside the reactor 19 and includes the reaction of the partially treated LFTL with hydrogen gas on a bed, such as a fixed bed, of a catalyst (not shown). As hydrogen is consumed during this process, hydrogen may be replenished from a make up source of hydrogen 20 , where hydrogen may be typically free of H 2 S. The process may be carried out at a pressure between about 1 MPa and about 15 MPa, for example, about 4 MPa. The required pressure can be generated and maintained using the compressor 23 .
The exothermic reactions occurring in reactor 19 may lead to a temperature increase. In order to control the temperature in the reactor the reacting fluid may be cooled (quenched). Such quenching can be achieved by supplying cool hydrogen via line 21 . Upon completion of this stage of hydrogenation, the partially hydrogenated product then may exit the reactor 19 via the line 22 , then may be directed to the separator 24 . After the process of separation, the final product can exit the system 100 as the stream 25 and then may be directed to fractionation.
Another embodiment of a system that can be used is shown by FIG. 2 illustrating the system 200 comprising two hydrotreatment reactors 29 and 40 . These reactors may be the same or different. In the exemplary system 200 shown by FIG. 2 , the reactor 29 may use a nickel/molybdenum catalysts such as KF-647 or KF-846, and the reactor 40 may utilize a platinum/palladium catalyst.
The LFTL feed 26 can be mixed with the hydrogen gas 27 that can be supplied at a rate between about 170 and about 840 m 3 per 1 m 3 of the LFTL. The LFTL/H 2 mixture can be then pre-heated to the desired temperature (e.g., 200° C. and about 370° C., such as about 315° C.) and can be then directed to the first hydrotreatment reactor 29 .
The process of hydrogenation then occurs inside the reactor 29 and includes the reaction of the LFTL with hydrogen gas on a bed of a catalyst (not shown). Hydrogen may be replenished from a make-up source of hydrogen 28 , and hydrogen supplied from this source may contain some amount of H 2 S. The process may be carried out at a pressure between about 1 MPa and about 15 MPa, for example, about 4 MPa. The required pressure can be generated and maintained using the compressor 33 .
The exothermic reactions occurring in reactor 29 may lead to a temperature increase. In order to control the temperature in the reactor the reacting fluid may be cooled (quenched), which can be achieved by supplying cool hydrogen via line 30 . The partially hydrogenated product then may exit the reactor 29 and be directed via the line 31 into the separator 32 , where water is separated as the stream 37 . The product may exit the separator 32 via the line 34 , and may then be directed to stripper 35 , where the H 2 S gas is removed as the stream 36 . The product may then exit the stripper 35 via the line 38 , and may then be directed to the second hydrotreatment reactor 40 , using the pump 39 . In an alternative, the product exiting the separator via line 34 may be directed to a fractionator 50 , that separates the hydrotreated light Fischer-Tropsch liquid composite into a plurality of fractions prior to hydrogenation in the second hydrotreating reactor 40 .
A later stage of the process of hydrogenation then occurs inside the reactor 40 and includes the reaction of the partially treated LFTL with hydrogen gas on a bed of a catalyst (not shown). As hydrogen is consumed during this process, hydrogen may be replenished from a make up source of hydrogen 41 , where hydrogen may be typically free of H 2 S. The process may be carried out at a pressure between about 1 MPa and about 15 MPa, for example, about 4 MPa. The required pressure can be generated and maintained using the compressor 42 .
The exothermic reactions occurring in reactor 40 may lead to a temperature increase. In order to control the temperature in the reactor the reacting fluid may be cooled (quenched) by supplying cool hydrogen via the by-pass line 44 . Upon completion of this stage of hydrogenation, the partially hydrogenated product then may exit the reactor 40 via the line 43 , then may be directed to the separator 45 . After the process of separation, the final product can exit the system 200 as the stream 46 and then may be directed to fractionation.
EXAMPLES
The following examples are provided to further illustrate the advantages and features of our processes and systems, but are not intended to limit the scope of this disclosure.
Example 1
Starting Material
The starting material that was used as a feed in hydrogenation was a commercially available light Fischer-Tropsch liquid and had the properties and characteristics shown in Table 1. In Table 1, the data for distillation temperatures show the boiling temperature at the beginning and the end of the recovery (by mass %) range. For example, the entry “10/20” in the property column and “100/142” in the value column signifies the boiling temperature of about 100° C. at the 10% mass recovery point and about 142° C. at the 20% mass recovery point.
TABLE 1
Properties of Starting Untreated LFTL
Property
Value
Specific gravity, g/cm 3
0.7884
API Gravity
47.98
Sulfur Contents, ppm* ) , mass
Less than 1
Nitrogen Contents, ppm* ) , mass
10
Oxygen Contents, mass %
5.9
Bromine Index
56
Acid Number
25.9
Distillation Temperature** ) , ° C.
IBP/5
21/86
10/20
100/142
30/40
167/190
50/60
418/454
70/80
266/296
90/95
336/373
EBP
469
Contents of Aromatic Compounds, mass %
One Ring
0.8
Two Rings
0.2
Three or More Rings
1.5
* ) parts per million
** ) determined in accordance with ASTM Specification D2887
*** ) determined in accordance with Institute of Petroleum Test IP-391
Example 2
Hydrogenation of the Starting LFTL
The starting untreated LFTL described in Example 1 was subjected to hydrogenation. The process was carried out in a two reactor (R-1 and R-2) configuration, with the removal of water between reactors. Nickel/molybdenum catalysts KF-647 and KF-846 were used in reactors R-1 and R-2, respectively. The catalysts were obtained from Albemarle Corp. of Baton Rouge, La.
The process yielded hydrotreated LFTL composite. The conditions of the process of hydrogenation are shown in Table 2, and the properties of the product are shown in Table 3.
TABLE 2
Operating Conditions Used for Hydrogenating LFTL
Operating Condition
Reactor 1 (R-1)
Reactor 2 (R-2)
Pressure, MPa
4.14
4.14
WABT* ) , ° C.
316
316
LHSV** ) , hr −1
2.5
1.67
Overall LHSV** ) , hr −1
1.00
Recycle Gas to Reactor 1, m 3
337
per 1 m 3 of LFTL
* ) weighted bed average temperature
** ) liquid hourly space velocity
TABLE 3
Properties of Hydrotreated LFTL Composite
Property
Value
Specific Gravity, g/cm 3
0.7387
API Gravity
60.04
Hydrogen Contents, mass %
15.39
Bromine Index
Less than 10
Oxygen Contents, mass %
Less than 0.02
Acid Number
0.005
Distillation Temperature* ) , ° C.
IBP/5
−9/66
10/20
88/126
30/40
152/175
50/60
197/218
70/80
255/287
90/95
331/369
EBP
510
Distillation Temperature** ) , ° C.
IBP/5
48/85
10/20
103/128
30/40
148/167
50/60
189/214
70/80
239/Solidified
90/95
N/A (Solidified)
EBP
N/A (Solidified)
* ) determined in accordance with ASTM Specification D2887
** ) determined in accordance with ASTM Specification D86, fractions are in volume %
The product obtained as described above and having properties shown in table 3 was then fractionated into two fractions to separate naphtha from diesel fuel. The first fraction (i.e., the naphtha fraction) had the IBP of about 149° C., and the second fraction (i.e., the diesel fraction) had the IBP above 149° C. The properties of the diesel fraction are provided in Table 4.
TABLE 4
Properties of the Diesel Fraction (IBP > 149° C.)
Property
Value
API Gravity
53.9
Cloud Point, ° C.
12.2
Flash Point, ° C.
57.2
Distillation Temperature* ) , ° C.
IBP/5
168/181
10/20
184/192
30/40
203/216
50/60
232/249
70/80
268/293
90/95
N/A//N/A (Solidified)
EBP
N/A (Solidified)
* ) determined in accordance with ASTM Specification D86, fractions are in volume %
As can be seen from Tables 3 and 4, in the process described above, it was not possible to complete the distillation according to ASTM Specification D86, and the diesel fraction had the cloud point which was quite high (about 12° C.), thus limiting the amount of the hydrotreated LFTL that can be used for blending into a diesel fuel. The following example demonstrates improvement of the process illustrated in Example 2.
Example 3
Further Processing of the Hydrotreated LFTL Composite
The product described in Table 3, obtained as discussed in Example 2 above (prior to fractionating the hydrotreated LFTL composite into the naphtha and diesel fractions), was further processed by additional hydrogenation, as follows.
The hydrotreated LFTL composite described in Table 3 was hydrogenated over a catalyst comprising about 0.45 mass % of platinum and about 0.45 mass % of palladium embedded on a support comprising a zeolite. The processing conditions for the process of hydrogenation are described in Table 5.
TABLE 5
Conditions for Processing the Hydrotreated LFTL Composite by
Hydrogenation over a Platinum/Palladium Catalyst
Operating Condition
Value
Pressure, MPa
6.9
LHSV, hr −1
1.0
Hydrogen Flow, m 3 per 1 m 3 of LFTL
1,011
Temperature, ° C.* )
265.6
291.7
* ) two separate experiments
As can be seen from Table 5, the process of hydrotreating was carried out at two different temperatures. Using the lower temperature, i.e., 265.6° C., may be suitable for improving the quality of the diesel fraction, while using the higher temperature, i.e., 291.7° C., may be beneficial if the product is to be used in the manufacturing of jet fuel with enhanced properties.
The product obtained under conditions shown in Table 5 was then fractionated and the light and the heavy naphtha fractions were removed by distillation. The properties of the remaining fraction are provided in Tables 6 and 7. Table 6 shows the properties of the diesel fraction that remained, as obtained after the hydrogenation carried out at the lower hydrogenation temperature of about 265.6° C.
TABLE 6
Properties of the Diesel Fraction After Processing the Hydrotreated
LFTL Composite by Hydrogenation over a Platinum/Palladium Catalyst
at 265.6° C.
Stream
Liquid Product
IBP/85° C.
85° C./143° C.
143° C./EBP
Yield, g
9,357
779
1,865
6,642
Yield, mass %
N/A
8.4
20.1
71.5
API Gravity
59.8
84.5
69.6
54.6
Specific Gravity, g/cm 3
0.7397
0.6550
0.7036
0.7602
Hydrogen Contents, mass %
N/A
N/A
15.78
15.33
Flash Point, ° C.
N/A
N/A
2.8
53.9
Cloud Point, ° C.
N/A
N/A
N/A
3.9
Pour Point, ° C.
N/A
N/A
N/A
−6.1
Viscosity at −20° C., cSt
N/A
N/A
1.185
N/A
Iron Contents, mass %
N/A
N/A
<0.00002
<0.00002
Reid Vapor Pressure, Pa
N/A
N/A
9,928.5
896.3
Micro Research Octane
N/A
N/A
<40
N/A
Number
Micro Motor Octane
N/A
N/A
<40
N/A
Number
Cetane Number
N/A
N/A
N/A
73.7
Distillation Temperatures* ) , ° C.
IBP
−1.1
−9.4
63.9
139.4
5
66.7
17.8
87.2
149.4
10
96.7
30.0
96.7
150.0
20
126.1
33.3
98.3
173.9
30
151.1
35.6
99.4
195.0
40
173.9
56.7
105.6
207.2
50
196.1
67.2
118.9
223.3
60
216.7
69.4
126.7
243.9
70
246.7
70.0
127.8
270.0
80
273.9
70.6
128.9
288.3
90
316.1
70.6
129.4
329.4
95
356.1
87.2
141.1
366.7
EBP
500.6
97.2
149.4
475.6
Distillation Temperatures** ) , ° C.
IBP
N/A
N/A
103.9
166.7
5
N/A
N/A
107.2
178.3
10
N/A
N/A
108.3
178.3
20
N/A
N/A
109.4
186.7
30
N/A
N/A
111.1
196.1
40
N/A
N/A
112.8
208.3
50
N/A
N/A
115.0
222.2
60
N/A
N/A
117.2
238.3
70
N/A
N/A
120.0
257.2
80
N/A
N/A
123.3
279.4
90
N/A
N/A
127.2
315.6
95
N/A
N/A
130.6
N/A
EBP
N/A
N/A
143.9
354.4
Recovery, mass %
N/A
N/A
98.7
93.9
* ) simulated, determined in accordance with ASTM Specification D2887
** ) Engler distillation, determined in accordance with ASTM Specification D86
As can be seen from the data presented in Table 6, the cloud point has been substantially improved compared with that of the diesel fraction recovered from the hydrotreated LFTL composite (see Table 4 for comparison of the respective cloud points), and the cetane number is quite high. Thus, the diesel fraction characterized in Table 6 may be used for blending with various diesel fuels. It may be also noticed that the difficulties previously experienced with the ASTM D86 distillation were eliminated.
Table 7 shows the properties of the kerosene/jet fuel fraction that remained, as obtained after the hydrogenation carried out at the higher hydrogenation temperature of about 291.7° C., and demonstrates that the product can be used as a high quality jet fuel blending component.
TABLE 7
Properties of the Kerosene/Jet Fuel Fraction After Processing the
Hydrotreated LFTL Composite by Hydrogenation over a
Platinum/Palladium Catalyst at 291.7° C.
Stream
Liquid Product
IBP/85° C.
85° C./135° C.
135° C./EBP
Yield, g
4,995
649
1,307
2,965
Yield, mass %
N/A
13.2
26.6
60.3
API Gravity
65.1
85.2
70.0
58.3
Specific Gravity, g/cm 3
0.7197
0.6530
0.7022
0.7456
Hydrogen Contents, mass %
N/A
N/A
15.78
15.44
Total Sulfur Contents, mass ppm
N/A
N/A
<0.05
0.07
Flash Point, ° C.
N/A
N/A
1.0
43.0
Cloud Point, ° C.
N/A
N/A
N/A
−35.0
Pour Point, ° C.
N/A
N/A
N/A
−57.0
Smoke Point, mm
N/A
N/A
N/A
39
Freeze Point, ° C.
N/A
N/A
N/A
−56.6
Viscosity at −20° C., cSt
N/A
N/A
1.137
3.250
Iron Contents, mass %
N/A
N/A
<0.00002
<0.00002
Reid Vapor Pressure, Pa
N/A
N/A
10,824.8
1,930.5
Micro RON
N/A
N/A
<40
N/A
Micro MON
N/A
N/A
<40
N/A
Distillation Temperatures* ) , ° C.
IBP
−22.2
−12.2
63.3
123.3
5
33.9
16.7
85.0
140.6
10
72.8
18.3
87.2
142.3
20
97.8
32.2
97.2
151.1
30
117.8
34.4
98.9
165.0
40
131.7
52.8
100.0
174.4
50
151.7
57.2
115.0
186.7
60
167.8
66.1
117.8
196.7
70
187.2
68.3
125.6
208.3
80
205.0
69.4
127.2
221.1
90
227.8
70.0
128.3
238.9
95
245.0
83.9
131.1
253.9
EBP
286.7
95.6
148.9
286.1
Distillation Temperatures** ) , ° C.
IBP
N/A
N/A
101.1
156.1
5
N/A
N/A
103.9
164.4
10
N/A
N/A
105.0
163.9
20
N/A
N/A
106.7
168.3
30
N/A
N/A
107.8
172.2
40
N/A
N/A
109.4
177.2
50
N/A
N/A
111.1
184.4
60
N/A
N/A
113.3
191.7
70
N/A
N/A
116.1
201.1
80
N/A
N/A
119.4
212.2
90
N/A
N/A
123.9
229.4
95
N/A
N/A
128.3
247.2
EBP
N/A
N/A
141.1
248.3
Recovery, mass %
N/A
N/A
97.0
95.8
* ) simulated, determined in accordance with ASTM Specification D2887
** ) Engler distillation, determined in accordance with ASTM Specification D86
Although our methods and systems have been described with reference to the above-discussed reactions and structures, it will be understood that modifications and variations are encompassed within the spirit and scope of the disclosure as defined in the appended claims. | A method for obtaining a petroleum distillate product is provided, the method includes subjecting an untreated light Fischer-Tropsch liquid to a two-step hydrogenation process, each step to be carried in the presence of a catalyst comprising an amorphous substrate having a metallic composition embedded therein. After the first step of hydrogenation, an intermediate hydrotreated light Fischer-Tropsch liquid is obtained, followed by the second step of hydrogenation thereof, obtaining the petroleum distillate product as a result. An apparatus for carrying out the method is also provided. | 2 |
BACKGROUND OF THE INVENTION AND PRIOR ART STATEMENT
The invention relates to a multi-stage refining method for organic bulk materials, according to the fluidized bed principle, for the production of low temperature carbonization gas, liquid products, and if necessary, coke, and an apparatus for performing this method.
A method for the gasification of carbonaceous materials is already known from the DE-OS 2947222, whereby a fluidized bed and fine dust gasification, and if necessary, also a solid bed gasification, take place continuously in a reaction chamber comprising one or several stages. In the direction of the gas stream, a given existing solid bed gasification is followed by two superposed and continuous stages of a fluidized bed gasification, whereby the charge of the crude raw material takes place in the lower stage thereof. Furthermore, in the lower fluidized bed, there are also immersed one or several fine dust gasification chambers having gasification burners mounted on the outside of the reaction chamber.
The method serves exclusively for the recovery of gas, whereby the solid materials are practically completely utilized; the only remaining residue is ash or slag. The configuration of all of the gasification stages in one reaction chamber, however, allows only an insufficient variability of the execution of the method with respect to the production of additional products, as well as to the temperature ratios in the individual stages.
The recovery of liquid products from a gas having compositions which are variable only within narrow limits, therefore is possible only at a high cost. The method further requires high energy consumption, and is unsuitable for the large-scale processing of carbonaceous materials. This deficiency, furthermore, results from the construction of the reactor, which requires high material and technical production expenses.
A method for the production of oil, gas and coke from coal according to the fluidized bed principle is known from the DE-OS No. 2939976. This is a multi-stage method comprising a grinding, a drying, a previous heating, two pyrolysis stages, as well as a stage for the partial gasification and heat development. The overhead streams of individual stages are thereby guided to the fluidization and heating located at upstream stages. The heat for the method is recovered from the partial carbonization of the coal particles in the last stage.
This method allows the regulation of the quantity portions of the end product, however, it does not reveal any possibility for its practical realization, particularly for the large-scale utilization of coal.
A method and an apparatus for the rapid pyrolysis of lignite has already been proposed (WP C No. 10 B/2490798) consisting of a two-stage method according to the fluidized bed principle for the production of coke, gas and tar. The fluidization of the coal is performed in a dryer via an influx floor. The fluidizing medium is produced in a carbonization chamber which is charged in the recycling direction with a part of the vapors from the drying. The dried coal is discharged via a discharge dike and is charged via a conveying apparatus and an intermediary bunker into the pyrolysis reactor. A carbonaceous gas alien to low temperature carbonization is utilized as a fluidizing medium which is heated in a preheater. The fluidized bed, also built up on an influx floor, is furthermore indirectly heated by a heat exchanger, through which is flowing the offgas of an additional carbonization chamber. Subsequently, the offgas heats the preheater, and is utilized as a mixing component for the direct heating in the dryer. The discharge dike provided in both stages simultaneously serves for the regulation of the height of the fluidized bed, and thereby for the determination of the residence time allocated to the coal in each particular stage.
This method still needs improvements with respect to the solid material transport, the determination of the residence time allocated in the stages, and the degree of the energy efficiency. The method, combined with the corresponding equipment, causes energy losses during the solid material transport, and provides an insufficient variability with respect to the quantity portions and the quality of the end product.
The equipment, furthermore, comprises a relatively large amount of apparatus, so that a large-scale utilization of the method requires a high capital investment.
SUMMARY OF THE INVENTION
The object of the invention is to provide a method and an apparatus for the multi-stage refining of organic bulk materials leading to a large-scale material and energy utilization thereof. It guarantees the conversion of bulk materials of various quality, a high degree of energy efficiency of the method and the apparatus, and which can be realized with an economically advantageous investment, by providing a high variability with respect to quantity proportions and quality of the end product.
Another object of the invention is to provide a method and an apparatus for the multi-stage refining of organic bulk materials, so that, by assigning the refining stages in connection with carrying out the transport of the solid material, there results a high variability in the quantitative and qualitative working process; that energy recovered in the refining stages, as well as, if necessary, energy supplied from the outside, is exploited at the least possible loss, and that the equipment has a compact construction for a large-scale plant of low space requirements and high throughput capacity.
These and other objects and advantages of the present invention will become apparent from the description which follows.
According to the invention, the object is solved, whereby the solid material transport of each refining stage takes place individually from the charge side to the opposite side and that the solid material transport is performed by gravity from one refining stage to the subsequent one, via a combined discharge/charge chute; that if the production of coke is omitted, subsequently to the degasification process, there follows an immediately continuous additional refining stage, which can be configured either as a carbonization stage or as a gasification stage; and that the necessary energy requirement of all the refining stages is selectively recovered either from the individual refining stages, or is supplied from the outside, or by a combination of these two possibilities, whereby the heat transmission occurs either directly or indirectly.
For the execution of the method with a continuous gasification stage, which is heated indirectly by the offgas of a carbonization chamber, the carbonization chamber simultaneously serves for preheating a mixture of a part of the gasification gas and/or water vapor, which is supplied directly to the gasification stage. By means of the offgas of the carbonization chamber, if necessary, after a subsequent heating in a second carbonization chamber, there also takes place an indirect heating of one or more degasification stages, through which the gasification gas passes directly.
A subsequent carbonization step following the degasification stage is charged with air, the gasification gas flows directly through the degasification steps, which furthermore are indirectly heated by the offgas of a carbonization chamber.
A further execution of the method consists in that the offgas of the carbonization chamber is supplied as a fluidizing medium to the drying stages which, furthermore, are alternatively heated indirectly by a part of the gasification or carbonization gas and/or are charged with a part of the vapors from the drying.
The dust removed from the drying stages is transferred to a separate low temperature dust carbonization.
The apparatus according to the invention consists in that the refining stages are configured one below another in a reactor having a rectangular cross section, separated from each other by the individual influx floor or a floor impermeable to gas, and connected to each other by individual, combined discharge/charge chutes which are located on opposite sides, and that the existing individual cells, each comprising a reactor, carbonization chambers and preheaters are aligned in a battery. One of the configurations of the apparatus consists in that each two adjacent cells are provided with a common separation wall, and that the corresponding combined discharge/charge chutes of these cells are positioned on both sides of this separation wall which is discontinuous in this area.
Other configurations consist in that the assigned preheater of a refining stage is an integrated component of the corresponding carbonization chamber; that the cells of a battery are connected in parallel with respect to bulk material charge and product discharge; and that to a corresponding number of cells of a battery, there is assigned an additional cell for the low temperature dust carbonization.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in detail by the following exemplified embodiment. The corresponding drawings show in schematic representation:
FIG. 1: a flow diagram of the method,
FIG. 2: a partial representation of the apparatus according
to the principle, and
FIG. 3: a configuration of a battery of a large-scale plant seen from the top.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is directed to a method for the multi-stage refining of orgianic bulk materials according to the fluidized bed principle, for the production of low temperature carbonization gas, liquid products and, if necessary, coke and an apparatus for the execution of the method. The method makes possible the large-scale material and energy utilization of bulk materials, with the object of achieving a high variability in quantitative and qualitative executions of the method, a compact construction of the apparatus and a high throughput performance at low space requirements. The method is characterized by the refining stages, where there occurs an exactly defined solid material transport, allowing the number and the kind of refining stages to be selected within a large range, and providing that the energy requirement of the refining stages are very variable. The appartaus consists of refining stages which are configured one below another in a reactor having a rectangular cross section, separated from each other by the individual influx floor or a floor which is impermeable to gas, and connected to each other by individual combined discharge/charge chutes located on opposite sides, and the individual existing cells, which are aligned in a battery, include a reactor, carbonization chamber and preheater.
Following is a glossary of terms and phrases (and reference numerals), and apparatus elements and members, as employed in the present invention.
GLOSSARY
1. Drying chamber
2. Degasification chamber
3. Refining chamber
4. Bulk goods
5. Discharge/charge chute
6. Discharge/charge chute
7. Carbonization chamber
8. Gasification chamber
9. Water
10. Offgas
11. Carbonization chamber
12. Air
13. Carbonization
14. Ash
15. Vapors
16. Dust
17. Discharge dike
18. Bulk goods charge
19. Influx floor
20. Floor
21. Ash discharge
22. Sealing part
23. Reactor
24. Separation wall
25. Gas product discharge
26. Coke product discharge
27. Natural gas
Referring to the drawings, the flow diagram according to FIG. 1 shows in simplified form only a drying stage 1 and a degasification stage 2, at the outlet side of which is connected the refining stage 3. The bulk goods 4 are charged into the drying stage 1. After the drying, the transfer through the combined discharge/charge chute 5 to the degasification stage 2 positioned underneath it occurs, in which the low temperature coke carbonization of the bulk goods is performed. The coke is transported via an additional discharge/charge chute 6 in the subsequent refining stage 3. The charging of the refining stages with the fluidizing medium takes place in counterflow thereof. A continuous carbonization stage 3a or a gasification stage 3b increases the production of low temperature carbonization gas and/or liquid products. For the gasification of the coke, the fluidized bed in this refining stage 3 is indirectly heated by the offgas 10 of a carbonization chamber 7, which simultaneously serves for the preheating of a mixture consisting of a part of the gasification gas 8 and water vapor 9, which is supplied to the fluidized bed as a fluidizing medium. The offgas 10, if necessary, is heated again in a second carbonization chamber 11, and is supplied for the indirect heating of the fluidized bed through the degasification stage 2. The gasification gas 8 thereby represents the fluidizing medium for the degasification stage 2.
In the carbonization of the coke in the refining stage 3, this stage is charged with air 12, and the carbonization gas 13, which is utilized as a fluidizing medium, flows through the degasification stage 2, which is indirectly heated by the offgas 10 of the carbonization chamber 11. Ash is discharged from the carbonization or gasification stage 3.
If there is no continuous refining stage 3 after the degasification stage 2, then the carbonization chamber 11 performs the indirect heating of the fluidized bed in the degasification stage 2, by means of offgas 10, whereby the carbonization chamber 11 simultaneously also serves for preheating a fluidizing medium, such as, for instance, natural gas 27, which is directly supplied to the degasification stage 2. In this case, the coke product discharge 26 is located at the degasification stage 2. The low temperature carbonization gas is discharged in each variation of the method through the gas product discharge 25 of the degasification stage 2 and is transferred for condensation.
The offgas 10 of the carbonization chambers 7, 11 is directly supplied to the drying stage 1 as a fluidizing medium which, additionally, is also alternatively heated indirectly by a part of the carbonization gas 13 or the gasification gas 8, and/or is charged with a part of the vapors 15 from the drying. Furthermore, by means of a suitable filter, the dust 16 is removed from the vapors 15 and transferred to a separate low temperature dust carbonization. In the apparatus according to FIG. 2, the solid material transport of each refining stage is indicated respectively occurring from the feeder side to the opposite side, whereby the residence time of the bulk goods in the refining stages is derived from the given width of the reactor in relationship to the height of the discharge dike 17.
The drying stage 1 has a bulk goods charge 18 and the influx floor 19, over which the fluidized bed is formed. Between the drying stage 1 and the degasification stage 2 there is provided a floor 20 which is impermeable to gas, and the two stages are connected to each other by the combined discharge/charge chute 5. In the degasification stage 2 and the refining stage 3, there are also provided influx floors 19, whereby these stages are separated from each other by an influx floor 19, and connected to each other by the discharge/charge chute 6. The ash discharge 21 is provided for the removal of the ash 14. In the bulk goods charge 18, the ash discharge 21 and the discharge/charge chutes 5, 6, there are located the sealing parts 22 for the charge of the solid materials and for the gas-tight separation of the refining stages.
The cells comprising the reactor 23 and the carbonization chambers 7, 11 with integrated preheaters are aligned to a battery according to FIG. 3. Each two adjacent cells have a common separation wall 24, whereby the discharge/charge chutes 5, 6 are positioned on both sides of this separation wall 24, which is discontinuous in this area. Each two cells, therefore, are provided between the same refining stages with a common discharge/charge chute 5, 6. The cells of a battery are connected in parallel with respect to the bulk goods charge 18 and the product discharges 25, 26. The battery configuration in FIG. 3 comprises two rows of 15 cells each, whereby one cell of each row performs the low temperature carbonization of the dust 16 removed from the drying stage 1 of the remaining cells.
The dimensions of the reactor 23 can be, for instance, 1.5 m in width, and 0.7 m in depth. The battery power at 30 cells is approximately 1800 t/d.
For the formation of stabilization zones over the fluidized beds, the reactors 23 in the individual refining stages can be provided with increasing expansions in vertical direction to the longitudinal axis of the battery.
The space between the battery rows is utilized for the supply and discharge of gas, as well as for dust removal apparatus and other devices, such as, for instance, blowers.
In comparison to the known solutions, the invention has the following advantages:
The execution of the process guarantees an improved determination of the residence time and a favorable solid material transport, so that in combination with the number and kind of refining stages, which can be selected from a large range, there is achieved a high variability with respect to the quantity portions and the quality of the end product. Because of the large number of possibilities of providing the energy requirements in the refining stages, on the one hand, materials of various BTU ratings can be utilized for refining, and on the other hand, a high degree of energy effectiveness is assured. The work cycle of the method permits a large-scale utilization.
Because of the building block solution of the reactor, the apparatus is highly compact, which allows a large-scale battery configuration. The construction of the apparatus further increases the variability of the execution of the method, improves the maintenance requirements of the equipment, and ensures the least loss in the utilization of the energy which is recovered in the process, as well as, if necessary, supplied from the outside. The battery configuration lowers the energy losses through radiation, and lowers insulation costs; it requires only a relatively low amount of material costs and space requirements, and thereby represents a low capital investment.
In summary, the present invention is characterized by the provision of a method for multi-stage refining of organic bulk materials according to the fluidized bed principle for the production of low temperature carbonization gas, liquid products and, if necessary, coke, whereby the bulk materials are submitted to a one or multi-stage drying, as well as a one or multi-stage degasification. The dust transported by the fluidizing medium from the drying stage is removed, and the low temperature carbonization gases are recovered in the degasification stages and are transferred to a condensation. The energy requirement of the individual refining stages is provided by recycling a part of the overhead stream in the recycling direction, by introducing of overhead streams in refining stages located upstream for simultaneous fluidization, or by supply from the outside in the form of direct and/or indirect heat transmission. A salient feature of the method is that the solid material transport in each refining stage each time takes place from the feeder side to the opposite side, and the solid material transport, performed by gravity, from a refining stage to the immediately continuous one is performed by a combined discharge/charge chute (5, 6). By omitting the production of coke, the degasification process is immediately continuous to a further refining stage (3), which can be configured either as a carbonization stage or as a gasification stage. The necessary energy requirement of all refining stages can be selectively recovered either from the individual refining stages, or can be supplied from the outside, or by a combination of these two possibilities, whereby the heat transmission occurs directly and/or indirectly.
In a preferred embodiment, the gasification stage is indirectly heated by the offgas (10) of a carbonization chamber (7), the carbonization chamber (7) simultaneously serves for preheating a mixture of a part of the gasification gas (8) and/or water vapor (9), whereby this mixture is supplied directly to the gasification stage, and the offgas (10) of the carbonization chamber (7), if necessary, after a subsequent heating also serves in a second carbonization chamber (11), in addition to the indirect heating of one or more degasification stages (2), through which the gasification gas (8) passes directly. Preferably, the carbonization stage is charged with air (12), and the carbonization gas (13) passes directly through the degasification stages (2), which are indirectly heated by the offgas of a carbonization chamber (11).
Typically, the offgas (10) of the carbonization chambers (7, 11) is transferred to the drying stage or stages (1) as a fluidizing medium, which, additionally, is alternatively indirectly heated with a part of the gasification gas (8) or the carbonization gas (13), and/or is charged with a part of the vapors (15) from drying. Preferably, the dust (16) of the drying stages (1) is transferred to a separate low temperature dust carbonization.
With regard to the apparatus aspect of the present development, the present apparatus for multi-stage refining of organic bulk materials, is specifically intended for the execution of the method as described supra. The apparatus includes one or several drying stages and one or several degasification stages, as well as, if necessary, a carbonization or gasification stage. The bulk materials are formed into a fluidized bed over the influx floor, whereby the bulk materials are conveyed by feeder and discharge apparatus from one refining stage to the subsequent one, and on which aggregates, such as carbonization chamber and preheater, are directly, pressure-tightly mounted. A salient feature of the apparatus is that the refining stages are configured one below another in a reactor (23) having a rectangular cross section, separated from each other by the individual influx floor (19), or a floor (20) which is impermeable to gas, and connected to each other by individual combined discharge/charge chutes (5, 6) positioned on opposite sides. The individual cells including a reactor (23), carbonization chambers (7, 11) and preheaters are aligned in a battery. Preferably, each two adjacent cells are provided with a common separation wall (24), and the combined discharge/charge chutes (5, 6) corresponding to each other of these cells are located on both sides of this separation wall (24), which is discontinuous in this area. Typically, a preheater assigned to a refining stage is an integrated component of the corresponding carbonization chambers (7, 11).
In a preferred embodiment of the present apparatus configuration, the cells of a battery are connected in parallel with respect to the bulk goods charge (18) and product discharges (25, 26). Preferably, an additional cell for low temperature dust carbonization is assigned to a corresponding number of cells of a battery.
It thus will be seen that there is provided a method and apparatus for multi-stage refining of organic bulk materials which attains the various objects of the invention and is well adapted for the conditions of practical use. As numerous alternatives within the scope of the present invention will occur to those skilled in the art, besides those alternatives, variations, embodiments and equivalents mentioned supra and shown in the drawings, it will be understood that the present invention extends fully to all such alternatives and the like, and is to be limited only by the scope of the appended claims, and functional and structural equivalents thereof. | An apparatus for the multi-stage refining of organic bulk materials according to the fluidized bed principle comprising a plurality of horizontally aligned cells (23) including an upper drying chamber (1), a middle degasification chamber (2) and a lower refining chamber (3) separated from each other by an individual gas permeable floor (19) or a gas impermeable floor (20). Adjacent cells are connected to each other by common discharge/charge chutes having vertical separation walls extending therein. | 2 |
BACKGROUND OF THE INVENTION
The field of this invention is positioning controls for variable displacement, axial piston pumps.
U.S. Pat. Nos. 2,733,666 to Poulos, and 2,977,891 to Bishop, show use of pressurized fluids available at the back plate. In these patents the fluid is used in different ways and for different uses than the present invention discloses. In U.S. Pat. No. 2,733,666, the fluid is channeled from the back plate to the opposite end of the cylinder barrel to re-engage the barrel with the back plate when they become disengaged as described in column 1, lines 27-55. In these two patents, the back plate is called a valve plate. In U.S. Pat. No. 2,977,891, the fluid is used to act on a piston system which regulates clearance between back plate and rotor of a radial piston pump as described in column 1, lines 53-63; in the last seven lines of claim 20; and as shown in FIG. 13.
Applicants know of no prior art using pressurized fluid to serve as a hydraulic stop in a cam plate positioning actuator to prevent the actuator from hammering on the back plate. This hammering of metal on metal occurs when the actuator is close to its fully retracted position, which is when the pump is working close to full displacement. The hammering of the movable part of the actuator against the back plate causes noise, wear, and vibration but is usually of short duration, occurring just before and just after the actuator is fully retracted. While fully retracted, the movable part is forced against the back plate thus preventing hammering. The hammering is caused by the varying forces exerted on the cam plate by pump pistons. In many hydraulic systems the pump seldom reaches full displacement, and therefore the problem does not occur. There are also many systems where the hammering is of such short duration that it is not objectionable or in some cases, unnoticeable. There are systems, however, where the noise, wear, or vibration of this hammering is undesirable. It is to those systems that this invention is directed.
SUMMARY OF THE INVENTION
The principal object of this invention is to eliminate noise, vibration, and wear in a cam plate positioning actuator of a variable displacement, axial piston pump when a movable part of the actuator is close to full retraction and hammers on a back plate.
Another object of the invention is to attain the foregoing objective by minor changes in the actuator and back plate of a conventional pump using an available source of pressurized fluid.
The gist of this invention is an automatic interposing of a hydraulic stop within the cam plate positioning actuator, whenever it is close to full retraction, to prevent hammering of the actuator's movable part on the back plate whether the contacting parts be metal or non-metal. Hammering is caused by unbalanced forces of pump pistons on the cam plate causing the movable part of the actuator to pulsate and when the actuator is close to full retraction the movable part impinges upon the back plate. This invention comprises a valve to block off drainage and to retain some fluid in the actuator when it is close to full retraction. This provides the hydraulic stop and precludes the movable part from impinging upon the back plate. The retained fluid prevents any further retraction and serves as a cushion for the pulsating forces.
The valve which blocks off the drainage from the actuator comprises a portion of the movable part blocking off the drain port of the actuator when it is close to full retraction. Thus the drain port is automatically closed whenever and only when impingement of the movable part upon the back plate is about to occur. Leakage normally occurs between moving parts in pumps, thereby furnishing lubrication, and to replenish the fluid leaking from the actuator while its drain port is closed and it is acting as a hydraulic stop, a supply of fluid from a charging port is channeled to the actuator. The charging port is a relief port used in many axial piston pumps and is located in the back plate, in circular alignment with and between the pressure port and the suction port, at the point where the pump pistons are reaching the end of their pressure stroke. Its principal purpose is to reduce the bending moments on the pump drive shaft and its use in this invention is to provide a convenient source of pressurized fluid which is channeled to the actuator instead of to a sump which would be its normal destination. Other sources for the pressurized fluid can be used such as an auxiliary pump, oil from the pump pressure port or by collecting the fluid near the back plate as shown in the aforementioned U.S. Pat. No. 2,733,666, column 1, lines 27-29, and in FIGS. 2 and 3.
Variable displacement, axial piston pumps are controlled by a pressure or flow compensator or a combined pressure and flow compensator, an example of which is shown in U.S. Pat. No. 3,508,847 to Martin. The compensator, sensing the pressure and flow conditions in a circuit, adjusts displacement of the pump by either routing pressurized fluid to the cam plate positioning actuator, which decreases displacement, or by routing the fluid in the actuator to drain, which increases displacement. The actuator decreases displacement by decreasing the tilt of the cam plate which is spring-biased toward the maximum tilt position. The actuator increases displacement by increasing the tilt. The routing of the pressurized fluid to and from the compensator will be more fully described in embodiments of this invention under "Description of the Preferred Embodiments".
The hydraulic stop can be appied to various forms of actuators according to the principle of this invention by using a valve to close off the drainage of the pressurized fluid in the actuator when it is close to full retraction and replenishing the pressurized fluid in the actuator while the valve is closed.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a view of the inside face of the back plate of the pump;
FIG. 2 is a sectional view taken on the line 2--2 of FIG. 1 through the back plate and also through an adjoining part of the pump showing an embodiment of this invention;
FIG. 3 is a sectional view similar to FIG. 2 but of another embodiment; and
FIG. 4 is an enlarged detail of a portion of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As can be seen in FIG. 1, the inner face of back plate 8 has a cylindrical-shaped, recessed shaft support 33, centrally located, and a series of arcuate openings 30, 26, and 32, spaced around and equidistant from the shaft support 33. These openings are a pressure port 30, located to one side of the shaft support 33; a charging port 26, located above the shaft support 33; and a suction port 32, located on a side opposite to the pressure port 30. A charging passage 16 within the back plate 8 leads upward from the charging port 26 to a circular, recessed chamber 24 in the back plate 8. A bore 35 passes through the back plate 8 and is surrounded by but separated from the chamber 24. A passage 14 within the back plate 8 extends upward from the chamber 24 and connects with a drain line 27 from a compensator illustrated schematically by block 6.
The hydraulic stop, in a first embodiment, can best be seen in FIG. 2 and in FIG. 4, which is an enlargement of a part of FIG. 2. The relevant parts of a conventional variable displacement, axial piston pump are shown. The back plate 8 serves as a support for a cam plate positioning actuator 20 and usually contains a compensator 6. One example of a commonly used compensator would be the pressure and flow compensator shown in U.S. Pat. No. 3,508,847 to Martin. The compensator 6 controls the cam plate positioning actuator 20 to adjust pump displacement to conditions the compensator 6 senses in the hydraulic circuit, as disclosed in detail in the above mentioned patent. Other compensators, including pressure compensators and flow compensators could also be used.
The charging passage 16 feeds pressurized fluid from the charging port 26 to the recessed chamber 24. The drain line 27 from the compensator 6 connects with the passage 14, thence with the chamber 24 and through it to the actuator 20, unlike a conventional compensator drain line which would drain to the interior of the pump case. A line 34 from the compensator 6 connects with the bore 35. A conventional cylinder block 38 rotates with its shaft, not shown, one end of which rests in the shaft support 33 shown in FIG. 1. The cylinder block 38 contains a plurality of axial pistons 36 which are reciprocated toward and away from the back plate 8 as the cylinder block 38 rotates while the pistons 36 are bearing against and engaged to a cam plate 15. A cam plate spring 22 biases the cam plate 15 toward a fully tilted position and its tilt is adjusted by the actuator 20. The actuator 20 may be in various forms, but the example shown in this embodiment comprises a closed end cylinder forming a movable part 10 sliding on a stud-shaped fixed part 12 attached to the back plate 8 by a mounting 31. The fixed part 12 has an axial bore 18 connecting the bore 35 in the back plate 8 with a chamber 19 which is enclosed by the movable part 10 and the outer end of the fixed part 12. A circular, recessed chamber 29 is located in the mounting end of the fixed part 12 and the chamber 29 adjoins and is freely connected with the circular, recessed chamber 24 in the back plate 8. A drain port 28 connects the chamber 29 with the inside of the pump case which serves as the sump. The drain port 28 is located in the sidewall of the fixed part 12 at a point where it will be covered and closed off by the movable part 10 whenever and only when the movable part 10 is close to the back plate 8. This condition occurs when the actuator 20 is close to being fully retracted which is the maximum displacement position of cam plate 15.
As used in this application, the words "close to being fully retracted", "close to full retraction", etc. mean that the movable part 10 of the actuator 20 is 2 to 5 millimeters or more from the back plate 8 and the fixed part 12 when the closing off of the drain port 28 occurs. The clearance of 2 to 5 millimeters is sufficient to prevent metal to metal contact of the movable part 10 due to pulsations in the actuator caused by reciprocating forces of the pistons 36 but it may be desirable to use a larger clearance for other reasons, such as limiting the displacement. In other designs of actuators, other arrangements of parts are used and it will be obvious where the clearance is needed between movable and fixed parts to implement the principle of providing the hydraulic stop by confining fluid within the actuator by closing off drainage and replenishing fluid when the actuator is close to full retraction.
In operation, when the compensator 6 senses that the circuit requires a greater supply of fluid, fluid is permitted to flow from the line 34 through line 27 to drain. This starts emptying chamber 19, under the influence of the spring 22. The fluid flows out through the bore 18, thence through the bore 35, line 34, compensator 6, line 27, passage 14, chamber 24, chamber 29, and out through the drain port 28 until the needs of the circuit are met. When the actuator 20 reaches a point close to full retraction, the movable part 10 slides over and closes off the drain port 28 and the remaining fluid is locked in the chamber 19 thereby stopping any further movement of actuator 20. This prevents the movable part 10 from striking the back plate 8, or the outer end of the fixed part 12, whichever is closer. The passage 16 conducts a supply of pressurized fluid from the charging port 26 to the chamber 24 where it replenishes fluid lost through normal leakage and thus keeps sufficient fluid in the chamber 19, while drain port 28 is closed, to keep the movable part 10 from striking the back plate 8 or other fixed parts, if closer.
Referring now to FIG. 3, a second embodiment of the hydraulic stop is shown with a different valving means for closing off the drainage of an actuator 20' and a different routing of the pressurized fluid to replenish the actuator 20' while the valving is closed. The relevant parts of the conventional variable displacement, axial piston pump are again shown in FIG. 3. A back plate 8' serves as a support for the cam plate positioning actuator 20' and usually contains the compensator 6 similar to that shown in FIG. 2. Compensator 6 controls the cam plate positioning actuator 20' to adjust pump displacement to conditions the compensator 6 senses in the hydraulic circuit.
The charging passage 16 feeds pressurized fluid from the charging port 26 to the recessed chamber 24. The drain line 27 from the compensator 6 connects, in a conventional manner, with a passage 17 and thence to the interior of the pump case which is the sump. The line 34 from the compensator 6 connects with the bore 35. The conventional cylinder block 38 rotates with its shaft, not shown, one end of which rests in a shaft support, not shown, in the back plate 8' but which is like the shaft support 33 shown in FIG. 1. The cylinder block 38 contains a plurality of axial pistons 36 which are reciprocated toward and away from the back plate 8' as the cylinder block 38 rotates due to the positioning of cam plate 15. The cam plate spring 22 biases the cam plate 15 toward the fully tilted position and its tilt is adjusted by the actuator 20'. The actuator 20' may be in various forms, but the example shown in this embodiment comprises a movable part 13 sliding within a closed end cylinder forming a fixed part 11, the closed end of which is attached to the back plate 8' by the mounting 31. The mounting 31 and adjacent closed end of the fixed part 11 has an axial bore 18' connecting the bore 35 with a chamber 19'. A check pin 7 is located in the inner end of the movable part 13. Pin 7, which is somewhat larger diameter than the axial bore 18', is biased toward the near end of the axial bore 18' by a check pin spring 21 and held in the movable part 13 by a bushing 9. A drain 23 in the movable part 13 drains the spring cavity within the movable part 13. A small diameter passage 25 connects recessed chamber 24 with the chamber 19'. The valving in this embodiment comprises the check pin 7 closing the end of the passage 18' whenever and only when the movable part 13 is close to the fully retracted end of its stroke.
In operation, when the compensator 6 senses that the circuit requires a greater supply of fluid, the fluid is permitted to drain from the line 34 through line 27 to the pump case, until the needs of the circuit are met or until the actuator 20' reaches the point close to full retraction. At that point the movable part 13, under the influence of the spring 22 moves the check pin 7 against the open end of the bore 18' and closes off the flow or fluid out of the chamber 19'. The fluid remaining in the chamber 19' stops the further retraction of the actuator 20' and serves as the hydraulic stop, preventing the movable part 13 from striking the closed end of the fixed part 11. Sufficient pressurized fluid from the charging port 26 flows through the passage 16 to the recessed chamber 24 and thence through the passage 25 to replenish the fluid lost from the chamber 19' due to normal leakage. Sufficient fluid is thus kept in the chamber 19' while the check pin 7 is closing off the opening to axial bore 18' to form the hydraulic stop and keep the movable part 13 from striking the closed end of the fixed part 11. Excess oil in chamber 19', supplied by charging port 26, positions movable member 13 against spring 22 until check pin 7 is unseated sufficiently to allow excess to exit through bore 18'. The hydraulic stop may be adjusted to points of less retraction by adjustment of the position where the check pin 7 closes off the flow through the bore 18'. | This automatic hydraulic cushioning device for cam plate positioning actuators on variable displacement, axial piston pumps eliminates the noise, vibration, and wear caused by hammering of the positioning actuator on the back plate when the actuator is close to full retraction. A supply of fluid under pressure, which is available at the back plate, is channeled to the cam plate positioning actuator. A valve in the actuator blocks off drainage of the fluid whenever the actuator is close to its fully retracted position. This retained fluid becomes a hydraulic stop and cushion for the actuator thus eliminating the hammering as well as the noise, vibration, and wear which results from the hammering. | 5 |
FIELD OF THE INVENTION
The invention relates to a force limiter for a vehicular seat belt restraint system, comprising a frame, a drum rotatably mounted in the frame for winding up belt webbing, a blocking disk coupled to the drum, and a blocking mechanism for selectively locking the blocking disk to the frame in a non-rotatable arrangement.
BACKGROUND OF THE INVENTION
The intention in providing a force limiter is to limit the force maximally active in the belt webbing when the blocking system is activated to a value which is uncritical for the restrained vehicle occupant. For this purpose a torsion rod arranged within the drum may be used, for example, which is connected non-rotatably to the drum, on the one hand, and to the blocking disk on the other. In the case of restraint, when a torque as predetermined by the dimensioning of the torsion rod is exceeded, the drum can be rotated relative to the belt retractor with twisting of the torsion rod, belt webbing thereby being withdrawn from the drum and, due to the occurring plastic deformation of the torsion rod, energy is depleted to prevent any further increase in the forces acting in the seat belt.
A torsion rod having the deformation properties with good reproducibility as required for a force limiter is a complicated component.
SUMMARY OF THE INVENTION
The invention provides a force limiter for a vehicular seat belt restraint system in which the blocking disk is axially held at one axial end of the drum and is coupled to the drum by at least two torsion elements anchored to the opposite end of the drum. By employing several torsion elements in parallel it is easily possible to adjust the force level at which the limiting action occurs, to a desired value, simply by using an appropriate number of torsion elements. Each individual torsion element can be simply configured as a metal bar, for example, as a wire section.
One advantage particular to the force limiter in accordance with the invention is that due to a simple further development a force limiting characteristic can be achieved having a degressive profile, i.e. in which the force level is reduced with increasing length of belt webbing withdrawn, resulting in optimum vehicle occupant protection in combination with an inflatable restraining means (gas bag), since on starting of the restraining action of the inflatable restraining means lower belt forces are desired in order to optimize the overall load by the belt webbing and the inflatable restraining means. In accordance with the preferred embodiment of the invention the torsion elements are inserted in openings passing through the blocking disk and protrude from these openings at the side of the blocking disk facing away from the drum; at least one of the torsion elements has a smaller axial length than the other torsion elements. When the torsion elements are twisted about each other their axial length is shortened at the same time. Thus, with increasing twisting, the length of the end sections of the torsion elements protruding from the through-openings becomes smaller. When a predetermined angle of rotation between drum and blocking disk is attained, the shorter torsion element is pulled out of the corresponding through-opening in the blocking disk totally, this torsion element then counteracting any further twisting by only little remaining resistance. Accordingly, the force is limited to a lower force level. By grading the axial length of several torsion elements the force limiting characteristic can be varied in a broad range.
It is especially of advantage in a further embodiment of the invention when the blocking disk is mounted so as to be shiftable on the drum in the axial direction. The axial shifting of the blocking disk on the drum is then effected by means of a positioning system which responds to such parameters as weight of the occupant, collision intensity or actuation of the gas bag. Due to the blocking disk being axially shifted, the level in limiting the force is varied very simply. When vehicle occupant weight, or collision intensity is low the level in limiting the force is thus so low that the risk of injury is minimized. On the other hand, when the vehicle occupant weight or collision intensity is higher or in the absence of the restraining action being supported by an inflatable restraining means (gas bag), the force needs to be limited at a higher level to prevent the vehicle occupant from too big a forward displacement in the vehicle.
Further advantages and features of the invention read from the following description of several embodiments and from the drawing, to which reference is made, and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side view of one embodiment of the force limiter in its condition prior to force limiting becoming active;
FIG. 2 shows the force limiter after having been active;
FIGS. 3a, 3b and 3c are various embodiments of the arrangement of several rod shaped torsion elements of the force limiter;
FIG. 4 is a diagram illustrating the force limiting characteristic of the force limiter in accordance with the invention as compared to that of a conventional force limiter; and
FIG. 5 shows a further embodiment of the force limiter in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment of the force limiter as shown in FIG. 1 a drum 12 is rotatably mounted in a frame such dimensioned as to be capable of bearing load, for securing to the vehicle body, whereby the drum 12 may be the belt reel of a belt retractor, it also being possible that the force limiter is designed as a limiter at an end fitting. The belt webbing 14 of a seat belt is wound up on the drum 12. The drum 12 consists of two flanges 12a, 12b axially spaced away from each other, a hollow cylinder 12c connecting the latter and forming a shell surface area, and a number of bar-shaped torsion elements 16 arranged parallel to each other and in axial direction, of which one axial end each is anchored to the flange 12a whilst the respective other axial ends protrude over through-openings in the flange 12b. The hollow cylinder 12c consists of two portions to enable a rotation of the flanges 12a and 12b relative to each other. The belt webbing 14 is secured to the portion of the hollow cylinder 12c which is fixedly connected to the flange 12a, shown on the left side of FIG. 1. A blocking disk 18 provided on its outer circumference with a blocking toothing is located on the outside of the one flange 12b from which the ends of the torsion elements 16 protrude. The blocking disk 18 is provided with through-openings in line with those of the flange 12b. The axial length of the torsion elements is dimensioned such that their ends also protrude from the through-openings of the blocking disk 18. In the preferred embodiment the torsion elements differ in length axially, however.
Swivably mounted on the frame 10 is furthermore a blocking pawl 20. This blocking pawl 20, like the blocking toothing on the outer circumference of the blocking disk 18, is a component of a blocking mechanism for selectively blocking the blocking disk 18 to the frame 10 in a non-rotatable arrangement.
When the blocking mechanism is activated the blocking pawl 20 is caused to engage the blocking toothing of the blocking disk 18, holding it non-rotatably relative to the frame 10. Despite this the belt webbing 14 wound up on the drum 12 can be withdrawn from the latter when the torsion elements 16 are twisted about each other as soon as a defined torque is exceeded. This condition is illustrated in FIG. 2. The torsion elements 16, which can be simple pieces of metal wire having a round cross-section, are twisted about each other, as a result of which their axial length is correspondingly reduced. It is evident from FIG. 2 that one of the torsion elements 16a is still maintained in the corresponding through-opening of the blocking disk 18 whilst another torsion element 16b, shorter in length, has already been pulled out of the corresponding through-opening of the blocking disk 18. This torsion element 16b then contributes only little to the resistance presented by the torsion elements in counteracting any further mutual rotation of the flange 12a, 12b. Accordingly, depending on the grading of the length of the various torsion elements the force level at which a force limitation occurs can be varied over a broad range.
An additional possibility of influencing the force limiting characteristic materializes from the blocking disk 18 being axially shiftable in response to parameters relevant to a collision, more particularly the weight or mass of the vehicle occupant, the collision intensity and the presence or activation of an inflatable restraining means (gas bag).
FIG. 4 is a diagram of various force limiting characteristics illustrating the profile of the force F in the belt webbing 14 versus the length L of withdrawn belt webbing. The force limiting characteristic 1 features, following a steep increase, a section of near constantly remaining force, followed by a section of progressively increasing force. This corresponds to the force limiting effect of a conventional force limiter, for example having a torsion rod as the torsion element. The force limiting characteristics 2, 3, 4, 5 and 6 illustrate the force limiting characteristics possible with the force limiter in accordance with the invention which may be strongly degressive as evident from curve 6. The variation in the characteristics is achieved, on the one hand, by suitably grading the lengths of the various torsion elements and, on the other, by axially shifting the blocking disk 18 as required.
FIGS. 3a, 3b and 3c show various embodiments for arranging the torsion elements in a radial plane of the drum 12, this arrangement being possible both symmetrically and non-symmetrically.
FIG. 5 partly shows a force limiter wherein the blocking disk 18 is mounted on the drum 12 so as to be axially shiftable. The blocking pawl 20 has a larger width, so as to be able to engage the blocking disk 18 even when the blocking disk 18 is axially shifted. The torsion elements have differing lengths and consequently a different axial position of the blocking disk 18 results in different force limiting characteristics. For axial shifting of the blocking disk 18, a threaded bolt 22 is provided, which is connected with the blocking disk 18 in its center of rotation in a non-rotational arrangement. At the end of the threaded bolt 22 facing away from the blocking disk 18, the threaded bolt 22 engages a threaded hole 24 of a coupling part 26. The coupling part 26 is secured to the shaft of an electric motor 28. By turning the shaft of the electric motor 28, the blocking disk 18 can be shifted in the axial directions indicated by the double-sided arrow shown in FIG. 5.
The electric motor is controlled by a control unit 30 which selects the axial position of the blocking disk 18 and consequently the force limiting characteristic by taking into account the weight of the vehicle occupant, the collision intensity and the gas bag activation. These parameters are detected by sensors 32 and 34, which are connected to the control unit 30. | A force limiter for a vehicular seat belt restraint system comprises a frame, a drum rotatably mounted in said frame for winding up a belt webbing, a blocking disk coupled to the drum, and a blocking mechanism for selectively locking said blocking disk to the frame in a non-rotatable arrangement. The blocking disk is axially held at one axial end of the drum and is coupled to the drum by at least two torsion elements anchored to the opposite end of the drum. | 1 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to the general art of ladders, and to the particular field of ladder stabilizers.
BACKGROUND OF THE INVENTION
[0002] Ladders are used extensively in a number of different situations such as construction, painting, building maintenance, etc. A ground supported ladder is generally used in an inclined position with its upper end portion resting on or against a suitable support. When a downwardly directed force is applied to the ladder by someone standing on it there is a nature tendency for the base of the ladder to move in a horizontal direction away from the supporting surface. Most serious accidents involving ladders of this type can be attributed to failure to provide a sound ladder footing. Long straight ladders and particularly extension ladders are inherently unstable when supported on uneven ground.
[0003] At times, the surface a ladder needs to be placed on is uneven or inclined. Placement of a ladder on an uneven surface renders the ladder unstable, which increases the possibility of the ladder toppling over, resulting in injury to workers. When such a ladder is used on irregular or sloping surfaces it is common practice to block or shim the ladder to compensate for the irregularity of the supporting surface. This is an extremely dangerous practice, but in many instances the practice cannot be avoided. This is particularly true where there is no provision for adjusting the effective length of the ladder side rails.
[0004] A number of devices have been developed to adjust the level of the ladder legs so that the ladder is firmly supported, even when placed on uneven surfaces. However, often, ladders may be unstable in a variety of planes. For example, the ladder may be subject to twisting on the top while subject to slipping in at least two planes on the bottom.
[0005] The inventor is not aware of any stabilizing device that can effectively stabilize a ladder, especially an extension ladder, in a multiplicity of planes. Without such effective multi-plane stabilization, there is a danger that the ladder can become unstable.
[0006] Accordingly, it is the general objective of the present invention to provide an improved ladder stabilizing unit which will provide a wide support base to assure firm footing for a ladder. It is a further objective of the invention to provide a ladder stabilizing device which may be readily adjusted to compensate for irregularities in the ladder supporting surface and may be adjusted to provide support in a variety of different planes.
[0007] Storage of ladders is another important consideration. A ladder is generally a bulky and sizable item and therefore may take up an inordinate amount of storage space. Any item that exacerbates this problem will likely not be successful. Accordingly, there is a need for a ladder stabilizer that can be moved into a position for storage and which will not unduly increase the storage bulk of a ladder.
SUMMARY OF THE INVENTION
[0008] The above-discussed disadvantages of the prior art are overcome by a ladder stabilizer system that supports the ladder, including an extension ladder, in a plurality of planes, including a roll plane, a tilt plane and a fall back plane. The stabilizer system includes an anti-roll bar on the top of each side rail of the ladder, a telescoping anti-slide leg on the bottom of each side rail for stabilizing the ladder in a slide plane with respect to the ladder, and a telescoping anti-fall back leg on the bottom of each side rail for stabilizing the ladder in a fall back plane with respect to the ladder. A safety harness system includes a cable that is mounted on one side rail of the ladder. The cable system permits adapting the harness to the chosen size of an extension ladder, and the harness adds a further safety feature to the ladder.
[0009] Using the ladder stabilizer system embodying the present invention will permit stabilization of a ladder, including an extension ladder, in a plurality of planes whereby the ladder is quite secure. The harness system adds further safety features to the stabilized ladder.
[0010] Other systems, methods, features, and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the invention, and be protected by the following claims.
BRIEF DESCRIPTION OF THE DRAWING FIGS.
[0011] The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.
[0012] FIG. 1 is a perspective view of a ladder stabilizer embodying the present invention.
[0013] FIG. 2 is a side elevational view of the ladder stabilizer shown in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0014] Referring to the figures, it can be understood that the present invention is embodied in a stabilized ladder unit 10 which is stabilized in a plurality of planes.
[0015] Ladder unit 10 comprises a ladder 12 which can be an extension ladder and includes two side rail units 14 and 16 . Each side rail unit includes a plurality of sections which slidably fit together. A first section 20 is a top section when the ladder is in use as shown in FIG. 1 and a second section 22 is a bottom section when the ladder is in use. A longitudinal axis 24 extends between the first section and the second section.
[0016] Each section of each side rail has an inner surface 26 , an outer surface 28 , a longitudinal axis 30 which extends between the direction of longitudinal axis 24 , a first side edge 32 which is an upper side edge when the ladder is in use and a second side edge 34 which is a lower side edge when the ladder is in use. A plurality of rungs, such as rung 40 , extend between the two side rail units. The rungs are located in a first plane P 1 on each section of the ladder.
[0017] An anti-roll unit 50 includes bars 52 and 54 . Each bar is mounted on the outer surface of a side rail of the first section of the ladder to extend away from the side rail on which it is mounted in a direction transverse to longitudinal axis 30 of the side rail on which it is mounted. The bars are located in first plane P 1 .
[0018] An anti-tilt unit 60 includes a telescoping leg, such as telescoping leg 62 , pivotally mounted on the outer surface of each side rail of second section 22 of the ladder to extend at an oblique angle θ 1 to side rail on which it is mounted. Each telescoping leg is located in a plane P 3 that is oriented at an oblique angle θ 2 to first plane P 1 .
[0019] An anti-fall unit 70 includes a telescoping leg, such as telescoping leg 72 , pivotally mounted on the upper side edge of each side rail of second section 22 of the ladder to extend at an oblique angle θ 3 to the side rail on which it is mounted. Each telescoping leg is located in a plane P 4 that is oriented at an oblique angle θ 4 to first plane P 4 and at an oblique angle θ 5 to the telescoping leg of the anti-tilt unit mounted on the side rail on which the telescoping leg of the anti-fall unit is mounted and at an oblique angle θ 6 with respect to the bars of the anti-roll unit. Multi-planar support is thus provided to the ladder by the above-discussed units.
[0020] Further support for a user is provided by a harness unit 80 mounted on the ladder. Harness unit 80 includes a cable housing 82 on one side rail, a cable guide 84 on the outer surface of one side rail of the first section of the ladder, a cable 86 which extends between the cable housing and the cable guide on one side rail of the ladder, a cable loop 88 movably attached to the cable, and a cable grip portion 90 attached to each cable loop. A cable control unit is contained in housing 82 and includes a spring unit or the like to rewind the cable when the ladder is collapsed and to allow the cable to be dispensed as the ladder is extended. A brake unit is also contained in the housing to catch the cable 86 when a sharp pull is exerted thereon in the manner of a motor vehicle seat belt so a user will be able to easily extend and retract the cable, but will have a stable and secure element to catch him if he begins to fall off of the ladder. In one form of the invention, cable 86 is formed of steel. A user wears a harness which connects to cable grip 90 to further secure himself to the ladder.
[0021] Use of stabilized ladder unit 10 will be understood by those skilled in the art based on the teaching of the foregoing disclosure. Accordingly, use of unit 10 will be only briefly discussed. A user extends ladder 12 to the desired height, then places anti-roll unit 50 against the support surface. The user then extends the legs of the anti-tilt unit 60 and the legs of the anti-fall back unit 70 to stabilize the ladder in two more planes. The user then ascends the ladder and connects his harness to grip portions 90 . Cables 86 unwind from housings 82 as the sections of the ladder are extended, and will rewind under spring bias or the like as the sections are collapsed for storage. The pivotal connections of the legs will permit the legs to be moved into the most desirable orientation for supporting the ladder and to be moved into a storage position next to the ladder when the ladder is to be stored so the ladder occupies the least volume during storage.
[0022] While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of this invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. | A ladder is stabilized in a plurality of planes so it will not twist, slide or fall once it is in place. Telescoping legs are mounted on each side rail of the ladder, a cable system acts as a harness rail and an anti-roll bar is mounted on top of each side rail. The cable system allows the harness to be extended on an extension ladder. | 4 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Ser. No. 60/780,393 filed Mar. 7, 2006 entitled G OLF T RAINING M ECHANISM A ND M ETHOD which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] Most people who have tried to learn the game of golf will agree that it constitutes one of the most challenging, frustrating, and demanding pastimes enjoyed, or at least practiced, by millions of people. The level of difficulty adds to the popularity of the sport. Most would also agree that enjoyment of the game increases with ability. Few golfers forget an unusually low scoring round they played during a given year.
[0003] The difficulty of the game is easy to explain. There are a number of factors that make the physics of hitting a golf ball understandably complex: (1) A golf club is longer than most of the racquets or bats used in other sports. (2) The contact area (club face) on a golf club is significantly smaller than the contact area of other sports-related striking implements. (3) A golf ball is smaller than almost any other ball found in striking sports. (4) The ball converts nearly all of the energy imparted on it to kinetic energy. (5) The ball spins at a high rate of speed. (6) The club head strikes the ball at over 100 miles per hour when swung correctly. (7) The golf swing uses nearly every muscle in the human body. (8) The ball flies hundreds of yards, leaving the margin for error very small for a decent following shot. (9) A good golfer uses fourteen different clubs during a round, each having a different length and a different club head. (10) A good golfer must be able to hit numerous different types of shots with each of his or her fourteen clubs. With all of these factors adding to the difficulty of the proper golf swing, it becomes easy to understand the healthy market for golf swing aids and instruction techniques.
[0004] Heretofore, however, the most popular training technique involves swing analysis by a golf professional, often with the aid of a video camera and a computer, followed by corrective instruction. Corrective instruction has involved verbal instruction, sometimes accompanied by a demonstration, followed by subsequent attempts by the student at correcting an identified problem.
[0005] There may be no substitute for the trained eye of a golf professional in identifying swing problems. However, the aforementioned correcting instruction technique is inefficient. Few people possess the athletic ability to listen to verbal instruction from a golf professional and then implement a swing change immediately thereafter. Golf swings, by necessity, are objects of habit. Like playing a complex musical piece on a piano, hitting a golf ball properly requires practice. Through practice, the muscles begin to receive repeated messages stored in the long-term memory of the brain, rather than immediate cognitive notions from the cerebral cortex. This “muscle memory” makes a long time golfer's swing look fluid while a beginner who has not yet memorized a swing, has an awkward swing. Changing a golf swing brings the swing instructions back from deep memory to the cerebral cortex. This is because the swing change is received aurally and must then be interpreted by the cerebral cortex to craft new swing instructions to the muscles. The result is an awkward-feeling swing, even if the golfer is executing the professional's instructions correctly.
[0006] Swing changes made in this manner, as mentioned above, feel awkward at first. The golfer usually leaves a golf lesson and heads for a driving range where he or she tries to “teach the muscles” the new swing through repetition. Hopefully, the new instruction set will work its way back into the memory of the brain, after hitting hundreds of golf balls, such that the golfer can eventually swing the golf club using the new swing without actively thinking about the differences. The swing becomes ingrained and the golfer becomes better.
[0007] However, quite often the new instructions being taught to the muscles get changed during the “memorizing phase” on the range. Swing changes necessary to correct a problem often seem counterintuitive. The golfer trying to implement a swing change battles the natural tendency of the brain to send its old memorized signals to the muscles rather than the new instructions from the cerebral cortex. Without substantial, frequent practice in the presence of a professional, the new swing that gets implemented is often different than the one the professional verbalized. Hence, usually swing changes are effectively made only in small, easy to remember increments.
[0008] A great many golf training tools are designed to provide the feedback necessary to keep a golfer focused on the proper new technique when a golf professional is not present. Some tools give visual feedback, others give aural feedback. Still others are result-based negative feedback. If a swing is improper, an obviously undesirable event happens. One example is a club with a hinged shaft that bends if swung improperly.
[0009] Though many of these tools are helpful teaching aides, none replaces or speeds the difficult conversion of verbal instruction into memorized muscle response. There is thus a need for teaching device and/or method that provides direct information to the muscles rather than through the ear of the golfer.
SUMMARY OF THE INVENTION
[0010] The present invention is directed to a device and technique that addresses the aforementioned need. Specifically, the present invention is a device and a teaching method that teaches a golfer to implement a swing change by teaching the golfer's muscles, rather than relying solely on educating the golfer's brain and the hoping the golfer properly trains his or her own muscles with the information provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of a component of the present invention;
[0012] FIG. 2 is a front elevation of the component of FIG. 1 with a golfer standing thereon;
[0013] FIG. 3 is a perspective view of a component of the present invention;
[0014] FIG. 4 is a perspective view of a component of the present invention;
[0015] FIG. 5 is a perspective view of a component of the present invention;
[0016] FIG. 6 is a perspective view of a component of the present invention;
[0017] FIG. 7 is a perspective view of a component of the present invention;
[0018] FIG. 8 is a plan view of the present invention being used on a golfer; and,
[0019] FIG. 9 is a plan view of the present invention being used on a golfer.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Turning now to the Figures and first to FIGS. 1 and 2 , there is shown a floor component 10 of the present invention. The floor component 10 includes a platform 12 on which a golfer stands when using the present invention. A back arm 14 extends in the direction of the backswing of the golfer and a fore arm 16 extends in the direction of the follow through of the golfer's swing. The arms 14 and 16 are angled away from the platform 12 and positioned such that they do not interfere with the golfer's swing. Each of the arms 14 and 16 has a plurality of attachment points 18 , the function of which is explained below. Preferably, the floor component 10 includes attachment points 18 that are vertically in line with the golfer's waist, knees, and ankles, at a minimum. The back arm 14 and fore arm 16 are shown as having telescopically adjustable lengths, an optional feature. To further enhance adjustability, the back arm 14 and fore arm 16 may be made to slide in the directions of arrows 15 and 17 , respectfully, or pivot around axes 19 and 21 , respectfully. Additionally, the floor component 10 also includes an optional attachment point 20 on or near the platform 12 , the function of which is also explained below.
[0021] FIG. 3 shows a belt 30 of the present invention. The belt 30 is sized to fit around the waist of a golfer and has a plurality of attachment points 32 placed in various positions around the outside of the belt 30 .
[0022] The present invention also includes one or more straps 40 like the one shown in FIG. 4 . The strap 40 is sized to fit around the ankle or knee of a golfer and is preferably adjustable such that it may also be used to fit around the wrist, arm, or thigh of a golfer as well. The strap 40 includes at least one attachment point 42 .
[0023] Turning now to FIG. 5 , there is shown a practice club 50 of the present invention. The practice club 50 is like a standard golf club with an attachment point 52 at the toe of the club head 54 . Attachment point 52 is shown as a loop though it could just as effectively be formed as a hole through the club head 54 or as a clamp-like device that attaches to a standard golf club. Using a band like the band 70 shown in FIG. 7 and explained below, the practice club 50 may be attached to an attachment point 18 on the back arm 14 .
[0024] FIG. 6 shows another practice club 60 of the present invention. The practice club 60 is like a standard golf club with an attachment point 62 at the end of the grip 64 . Using a band like the band 70 shown in FIG. 7 and explained below, the practice club 60 may be attached to the attachment point 20 of the floor component 10 . Though the attachment point 20 is shown extending from a front side of the floor component 10 , it may optionally be placed somewhere on the platform 12 in either a removable fashion or in a place that will not otherwise interfere with a golf swing.
[0025] FIG. 7 shows a band 70 of the present invention. Band 70 is formed of a stretchable material such as rubber, latex, or the like. Using the method of the present invention, explained below, a golf professional uses the band 70 to attach a golf club, such as practice club 50 or 60 , or a golfer wearing either a belt 30 , strap 40 , or combination thereof to an attachment point 18 or 20 of the floor component 10 of the present invention.
[0026] The physical components of the training technique of the present invention, explained above, provide a numerous ways in which a golfer may be attached to the floor component 10 of the present invention. However, a golf professional is needed to identify a swing flaw and use the present invention to correct that swing flaw using the training method of the present invention.
[0027] The method of the present invention thus begins with a swing analysis, not unlike those presently done by many golf professionals around the world. A golfer swings at a golf ball while a golf professional looks for swing flaws. Often, the golf professional will utilize video cameras and replay software so that he or she may review the swing in slow motion to analyze the swing more closely and show the golfer the flaw being corrected. However, a video camera is not crucial to practicing the method of the present invention.
[0028] Once a flaw is identified, the golf professional may decide to use assistive or resistive training, or both, to “teach the muscles” how to swing correctly. Both assistive and resistive training are made possible by the aforementioned components of the present invention. Each of these training techniques is now explained individually.
[0029] Assistive Training
[0030] Assistive training is a term used herein to describe a technique whereby a golfer's body is urged in a desired direction or configuration by the bands 70 of the present invention. Doing so shows the golfer what it feels like to correct a swing flaw rather than simply providing verbal instructions or showing the golfer the flaw on a video tape and expecting the golfer to reinstruct his or her muscles to correct the flaw. By guiding the muscles in the correct direction, the golfer is able to immediately imitate the proper swing after the bands 70 are removed. Hence, the golfer's muscles are “taught” rather than the golfer's brain, so to speak.
[0031] Reference is now made to FIG. 8 to demonstrate an example of where a golf professional might find assistive training useful. One common swing flaw is a failure to rotate the hips “through the ball” such that the hips face the target on the follow through. This is a flaw that is difficult to fix because concentrating on hip motion distracts the brain from making an otherwise fluid swing. The hips are a large component of a golf swing and affect almost all of the other components. Thus, simply telling the golfer to rotate their hips “through the ball” usually results in a hip slide, rather than a rotation, or throws of the timing of the swing enough so that the golfer can no longer make adequate contact with the ball.
[0032] FIG. 8 shows how a golf professional might attach a band 70 of the present invention between a golf student having a problem rotating his hips to the floor component of the present invention such that assistive training shows the golfer how to properly rotate his hips. The golfer 80 is shown in a cutaway through the torso for clarification. Hence, the golfer 80 stands on the platform 12 and addresses a ball 82 . A belt 30 is placed around the golfer's waist and a band 70 is wrapped around the golfer and attached to an attachment point 32 on the belt at one end, and at the other end to an attachment point 18 on the fore arm 16 of the floor component 10 . The band 70 is wrapped around the golfer in the manner shown such that the golfer's body will be urged to rotate in a counter clockwise direction, appropriate for a right-handed golfer.
[0033] The golf professional has many attachment points 18 and 32 from which to choose. Hence, the professional must decide which attachment points 18 and 32 to use based on the height of the golfer, the length of the band 70 and the desired strength of the assist. Stretching the band further results in stronger assistive training.
[0034] Furthermore, the example shown in FIG. 8 merely provides one assistive training technique for one golf flaw. The golf professional will quickly realize that between the plurality of attachment points 18 on both arms 14 and 16 , and the attachment points 32 and 42 provided by the belt 30 and straps 40 , almost every aspect of the golf swing can be taught through assistive training.
[0035] Additionally, the example shown in FIG. 8 provides only one way to use assistive training for that particular swing flaw. For example, if the golf professional noticed that the configuration of FIG. 8 results in a forward hip slide, another swing flaw, the band 70 could be wrapped further around the golfer's waist and attached to an attachment point 18 on the back arm 14 . Doing so would not only urge the golfer's torso to rotate in a counter clockwise direction, it would also urge the golfer rearward, thus preventing a forward hip slide.
[0036] Hence, the extreme flexibility of the device and method of the present invention is demonstrated. The need for knowledgeable professional assistance is also shown.
[0037] Resistive Training
[0038] Whereas assistive training “teaches” the muscles by showing the golfer what a flaw correction should feel like, resistive training “trains” the muscles by exercising them to work harder than they would during a normal golf swing. Resistive training works on the principle that if a muscle or muscle group performs a series of repetitions against unusually high strain or load, the muscle group will perform that same motion effortlessly when the strain or load is removed. This principle is practiced often by athletes. For example, many baseball players swing two bats, or one bat with weights attached prior to approaching the plate when it is their turn to bat. Having swung two bats or a heavy bat, swinging a normal bat will seem easy and effortless at the plate.
[0039] FIG. 9 shows an example of how resistive training might be used to correct the previously mentioned swing flaw whereby the golfer fails to rotate his hips “through the ball.” As in FIG. 8 , the golf professional has placed a belt 30 around the waist of the golfer, who is standing on the platform 12 of the floor component 10 . A band 70 is attached at one end to an attachment point 32 of the belt 30 and at the other end to an attachment point 18 on the back arm 14 . The band 70 is configured around the golfer 80 such that the golfer must exert extra force against the band 70 in order to rotate the hips properly. Doing so several times strengthens the necessary muscles and makes it obvious to the golfer what the desired result is. After a predetermined number of repetitions have been completed, the band 70 is removed and the golfer naturally rotates his hips properly during the next several swings.
[0040] Further Examples
[0041] The above description has discussed the basic premise of the present invention, and one skilled in the art will quickly realize the endless possibilities the present invention provides for unprecedented training capabilities. By way of example only, the following attachment combinations are also provided:
[0042] Knee Attachments for Right Handed Player:
[0043] 1. Assistive right knee: A band 70 is attached between a strap 40 on the right knee and the fore arm 16 . This teaches a player to feel how the knees should work together through the impact position and into the finish. This also assists in getting the hips to turn.
[0044] 2. Resistive right knee: A band 70 is attached between a strap 40 on the right knee and the back arm 14 . This trains the right knee to stay flexed on the takeaway. Most people straighten the right knee. This exercise illuminates how it should feel pushing off the right leg on the downswing. This also aids in hip turn when cord 70 is removed.
[0045] 3. Assistive left knee: A band 70 is attached between a strap 40 on the left knee and the fore arm 16 of the floor component 10 . This shows a golfer how it feels to have their left hip and knee bump forward on the downswing.
[0046] 4. Resistive left knee: A band 70 is attached between a strap 40 on the left knee and the back arm 14 of the floor component 10 . This forces the left knee to move forward on the downswing. Automatic implementation occurs after the strap 40 is removed after performing numerous repetitions with the strap 40 .
[0047] Hip Attachments for Right Handed Player:
[0048] 1. Assistive left hip: A band 70 is attached between a belt 30 near the left hip and the fore arm 16 of the floor component 10 . This promotes the left hip “bump” or initial move on the downswing.
[0049] 2. Assistive right hip: Shown in FIG. 8 and described above.
[0050] 3. Assistive left hip wrap: Combines #1 and #2 together using two bands 70 , one attached to the left hip and the other wrapped around the golfer as shown in FIG. 8 .
[0051] 4. Resistive left hip: Shown in FIG. 9 and described above. This forces a player to bump and rotate through the ball. It also promotes correct weight shift to the left side. Also aids in a better turn on the backswing by pulling left hip back with left shoulder.
[0052] 5. Resistive right hip wrap: A band 70 is attached between a belt 30 near the right hip and is fed around the back of the golfer to the fore arm 16 of the floor component 10 . This forces a player to bump and rotate through the ball. More tension around hips makes for a more prominent bump and rotation through the ball.
[0053] 6. Resistive right hip: A band 70 is attached between a belt 30 near the right hip and the back arm 14 of the floor component 10 . Promotes weight shift off of right side during the swing.
[0054] Ankle Attachments for Right Handed Player:
[0055] 1. Assistive right ankle: A band 70 is attached between a strap 40 on the right ankle and the fore arm 16 . This demonstrates a correct “rolling” motion of the right foot into the ball and through impact. A player is prevented from “squashing the bug” as in baseball/softball players.
[0056] 2. Resistive right ankle: A band 70 is attached between a strap 40 on the right ankle and the back arm 14 . This promotes correct “rolling” motion of right foot into the ball at impact after the band 70 is removed.
[0057] Using the Practice Club 50
[0058] 1. A band 70 is attached between the club head 54 at the attachment point 52 and the back arm 14 . Doing so is a resistive technique that promotes the golfer to turn the club over at impact after performing numerous repetitions using the practice club 50 .
[0059] Using the Practice Club 60
[0060] 1. A band 70 is attached between the end of the shaft at the attachment point 62 and the attachment point 20 on the floor component 10 . Doing so is a resistive technique that promotes the golfer to move back in the back swing and extend the club away from the body after performing numerous repetitions using the practice club 60 .
[0061] One skilled in the art will quickly realize that the invention has been shown and described for a right-handed golfer. A left-handed version of the present invention will simply be a mirror image of that shown and described. Moreover, as the floor component 10 is preferably symmetric along on axis through the center of the device, a left handed golfer may use the floor component 10 as described by simply hitting the ball in the opposite direction or turning the floor component 10 around.
[0062] Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. | Teaching a golfer a golf movement by applying a force to the muscles of the student while the student is performing the golf movement. The force being applied is either assistive or resistive in order to teach and train the student's muscles. Mechanisms for applying these forces are attachable to the body and typically extend from a portion of the body to a stationary object. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a projecting system and more particularly to a projecting system of having a prism between the polarizing beam splitter and the light source.
[0003] 2. Description of the Prior Art
[0004] Projectors are conventionally used in conference briefings in which a host projects data or graphics onto a screen for familiarizing attendants with a presentation. With the rapid development of technology, projectors are now widely used in other applications. With high-power hi-fi equipment, large-capacity digital video discs (DVDs), and the large images that can be generated by projectors, it is now possible to reconstruct at home visual and audio effects similar to those provided in a movie theater.
[0005] However, consumer projectors sold on market today typically have the disadvantage of insufficient brightness. For instance, after light is projected from a light source in a projecting system to a light-entering plane of a lens groups, the light is redefined through a polarizing beam splitter (PBS), reflected by a LCoS panel, and directed from a light-exit plane of the lens group to a projecting lens group. The projecting lens group then projects the corresponding image onto a screen. It should be noted that light projected from the light source onto the light-entering plane of the lens group is typically circular. However, as the light-entering plane of the lens group used for collecting light is built with a rectangular design, the mismatch between the light-entering plane of the lens group and the light produced from the light source often results in reduction of light and lowers the overall brightness of the display panel substantially.
SUMMARY OF THE INVENTION
[0006] It is an objective of the present invention to provide a projecting system for solving the disadvantage of having insufficient brightness in current projecting system.
[0007] According to a preferred embodiment of the present invention, a projecting system is disclosed. The projecting system includes: a light source; a lens group disposed on the exit of the light source, wherein the lens group comprises a polarizing beam splitter; and at least one rectangular prism disposed on one side of the prism group and between the polarizing beam splitter and the light source.
[0008] According to another aspect of the present invention, a projecting system is disclosed. The projecting system includes: a light source; a lens group disposed on the exit of the light source, wherein the lens group comprises a polarizing beam splitter; and a plurality of segmented prism disposed on one side of the lens group and between the polarizing beam splitter and the light source.
[0009] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 illustrates a perspective view of a projecting system according to a preferred embodiment of the present invention.
[0011] FIGS. 2-4 illustrate enlarged views of a prism of FIG. 1 according to different embodiments of the present invention.
[0012] FIG. 5 illustrates a perspective view of a projecting system according to another embodiment of the present invention.
[0013] FIG. 6 illustrates an enlarged view of the segmented prism shown in FIG. 5 .
DETAILED DESCRIPTION
[0014] Referring to FIG. 1 , FIG. 1 illustrates a perspective view of a projecting system according to a preferred embodiment of the present invention. Preferably, the projecting system could be constructed to project three-dimensional pictures or regular two-dimensional pictures, and an embodiment for projecting two-dimensional pictures is explained below. As shown in FIG. 1 , the projecting system includes a light source 12 , a lens 28 for collecting light, a lens group 14 , a liquid crystal on silicon (LCoS) panel 16 , a prism 18 disposed on a light-entering plane 22 and a projecting lens group 20 disposed on a light-exit plane 24 of the lens group 14 .
[0015] The light source 12 provides light required by the projecting system, in which the light source 12 could be composed of various light emitting elements including light emitting diodes (LEDs) or high intensity light bulbs. The lens 28 is situated between the light source 12 and the lens group 14 , and is preferably used to focus the light emitted from the light source 12 onto the light-entering plane 22 of the lens group 14 . Despite the lens 28 of this embodiment is composed of one single lens, the lens 28 could also be a composite lens structure with a plurality of lenses having focusing mechanisms, which is also within the scope of the present invention.
[0016] The lens group 14 is situated relative to the exit of the light source 12 , in which the lens group 14 could include a polarizing beam splitter (PBS) 26 coating to redefine the unpolarized light beam projected from the light source 12 into P-polarizing beam and S-polarizing beam. The defined P-polarizing beam and the S-polarizing beam are reflected from the LCoS panel 16 to the projecting lens group 20 . The projecting lens group 20 is composed of a plurality of lenses and situated relative to the exit-plane 24 of the lens group 14 and opposite to the LCoS panel 16 . Light reflected from the LCoS panel 16 are directed through the projecting lens group 20 to a screen (not shown) to display a corresponding image. In this embodiment, the light-entering plane 22 of the lens group 14 is rectangular, hence the prism 18 is preferably rectangular or square. Nevertheless, the shape of the prism 18 could also be adjusted according to the shape of the light-entering plane 22 of the lens group 14 , which is within the scope of the present invention. The prism 18 is disposed between the polarizing beam splitter 26 of the lens group 14 and the light source 12 , and is preferably adhered onto the light-entering plane 22 of the lens group 14 . As light entering the lens group 14 first passes through the prism 18 , the prism 18 is preferably used to adjust and gather the light entering the lens group 14 , such that the LCoS panel 16 could receive much stronger light.
[0017] Referring to FIGS. 2-4 , FIGS. 2-4 illustrate enlarged views of the prism 18 according to different embodiments of the present invention. As shown in the figures, the prism 18 is fabricated according to the light-entering plane 22 of the lens group 14 with a central region 30 and a peripheral region 38 . The peripheral region 38 of the prism 18 includes four sides, in which each sides has at least one inclined surface 32 , and the inclined surface 32 could have equal or different slopes. As shown in FIG. 2 , the peripheral region 38 of the prism 18 includes a total of four inclined surfaces 32 surrounding the rectangular central region 30 , in which each of the inclined surfaces 32 is a flat surface. However, one or more inclined surfaces 34 / 36 could be formed in the peripheral region 38 , as shown in FIG. 3 , and the inclined surfaces 34 / 36 could have same or different slopes therebetween. In addition to flat surfaces, the surface 32 of the peripheral region 38 of the prism 18 is fabricated with an arced profile, as shown in FIG. 4 . Overall, the peripheral region 38 of the aforementioned embodiments could be used to gather light emitted from the light source 12 to the lens group 14 , and the slope of the flat surface and degree of arced profile of the peripheral region 38 could all be adjusted according to the demand of the product.
[0018] Referring to FIG. 5 , FIG. 5 illustrates a perspective view of a projecting system according to another embodiment of the present invention. The projecting system of this embodiment could also be constructed to project three-dimensional pictures or regular two-dimensional pictures, and an embodiment for projecting two-dimensional pictures is explained below. As shown in FIG. 5 , the projecting system includes a light source 42 , a lens 58 for collecting light, a lens group 44 , a liquid crystal on silicon (LCoS) panel 46 , a plurality of segmented prisms 48 disposed on a light-entering plane 52 and a projecting lens group 50 disposed on a light-exit plane 54 of the lens group 44 .
[0019] Similar to the aforementioned embodiment, the light source 42 provides light required by the projecting system, in which the light source 42 could be composed of various light emitting elements including light emitting diodes (LEDs) or high intensity light bulbs. The lens 58 is situated between the light source 42 and the lens group 44 , and is preferably used to focus the light emitted from the light source 42 onto the light-entering plane 52 of the lens group 44 . Despite the lens 58 of this embodiment is composed of one single lens, the lens 58 could also be a composite lens structure with a plurality of lenses having focusing mechanisms, which is also within the scope of the present invention.
[0020] The lens group 44 is situated relative to the exit of the light source 42 , in which the lens group 44 could include a polarizing beam splitter (PBS) 56 coating to redefine the unpolarized light beam projected from the light source 42 into P-polarizing beam and S-polarizing beam. The defined P-polarizing beam and the S-polarizing beam are reflected from the LCoS panel 46 to the projecting lens group 50 . The projecting lens group 50 is composed of a plurality of lenses and situated relative to the exit-plane 54 of the lens group 44 and opposite to the LCoS panel 46 . Light reflected from the LCoS panel 46 are directed through the projecting lens group 50 to a screen (not shown) to display a corresponding image.
[0021] In contrast to the aforementioned rectangular prism 18 , a plurality of segmented prisms 48 is disposed on the light-entering plane 52 of the lens group 44 , in which the segmented prisms 48 are preferably composed of a frame consisting of four bar-shaped prisms. Referring to FIG. 6 , FIG. 6 illustrates an enlarged view of the segmented prism 48 shown in FIG. 5 . As shown in FIG. 6 , the segmented prisms 48 include at least one inclined surface 60 , in which the inclined surfaces 60 could have equal or different slopes therebetween. Similar to the aforementioned embodiment of using peripheral region 38 of the lens 18 for adjusting and gathering light entering the PBS, the inclined surface 60 of this embodiment is preferably used for gather light entering the lens group 44 , such that more lights are collected and gathered on the lens group 44 and the LCoS panel 46 for displaying much better images.
[0022] Despite the above embodiments are applied to a projecting system having one single LCoS panel as a base for projecting 2D images, the present invention could also apply the above embodiments to a projecting system with two LCoS panels for producing 3D images, which is also within the scope of the present invention.
[0023] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. | A projecting system is disclosed. The projecting system includes: a light source; a lens group disposed on the exit of the light source, wherein the lens group comprises a polarizing beam splitter; and at least one rectangular prism disposed on one side of the prism group and between the polarizing beam splitter and the light source. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a gun barrel base ring including an angular obturating ring mounted in a recess and means disposed between the base ring and the gun barrel for adjusting the axial play existing between the obturating ring and a breechblock.
A base ring of this type is disclosed in German Patent No. 1,578,046.A1, with particular reference to FIG. 1 thereof. According to this patent, manufacturing tolerances, particularly of the base ring, the wedge-type breechblock and an insert disposed in the breechblock, are compensated in that means are provided for adjusting the play between the base ring and the gun barrel as needed for the transverse movement of the breechblock. These means comprise twelve spacer rings of different thicknesses which are expensive to manufacture. Depending on the existing manufacturing tolerance, one of these twelve spacer rings is employed while the other eleven rings must be kept in storage near the gun. They are required, for example, for exchange if the base ring or the breechblock insert exhibits wear. It is therefore necessary to constantly check the supply of spacer rings at the gun and, moreover, they require much space in a storage depot.
SUMMARY OF THE INVENTION
It is an object of the present invention to reduce to a minimum the manufacturing and storage costs for the adjustment means required to adjust the necessary play between the obturating ring and the breechblock or the breechblock insert.
The above and other objects are accomplished according to the invention by the provision of an arrangement for axially adjusting play between an obturating ring of a gun barrel base ring and a wedge-type breechblock at the breech end of a gun barrel, including: a gun barrel base ring having first and second frontal faces, the first frontal face being adjacent a wedge-type breechblock of a gun barrel and having a recess opening toward the wedge-type breech block, and the second frontal face being adjacent the gun barrel and having an annular groove opening toward the gun barrel; an angular obturating ring supported in the recess; and a threaded ring adjustably disposed in the annular groove so as to be located between the base ring and the gun barrel for adjusting axial play existing between the obturating ring and the wedge-type breechblock.
By using a basically infinitely adjustable threaded ring, the present invention avoids in an advantageous manner the expensive manufacture of many spacer rings of different thicknesses and the complicated and space consuming storage of the spacer rings employed in the past.
The threaded ring has an internal and an external thread so that the stable position of the threaded ring within the base ring and the absorption of high axial forces that are transferred to the gun barrel is ensured. Moreover, the threaded ring is provided with adjustment means which permit, by simple rotation of the ring, an extremely accurate adjustability of, for example, 0.03 mm.
The adjustment means are configured as grooves which are uniformly distributed over the circumference of the threaded ring and whose free spaces are further advantageously usable for the space saving accommodation of thrust screws.
The present invention will now be described in greater detail with reference to an embodiment that is illustrated in the drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective, partial sectional view of the end of a gun barrel provided with a base ring, an obturating ring and an adjustable threaded ring according to the invention.
FIG. 2 is an enlargement of a region of the sectional view marked II in FIG. 1 and additionally shows sections of the breech ring and the breechblock.
FIG. 3 is a cross-sectional view of the base ring and the adjustment ring as seen along line III--III of FIG. 4.
FIG. 4 is an elevational view in the direction of the arrow IV in FIG. 3.
FIG. 5 shows an enlarged detail of an annular groove of the base ring as indicated at V in FIG. 3.
FIG. 6 is a cross-sectional view along line VI--VI of FIG. 4.
FIG. 7 is a top view of the threaded ring.
FIG. 8 is a cross-sectional view of the threaded ring.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 show the rear end of a gun barrel 12 and the seal region between a breechblock 20 that is transversely displaceable within a breech ring 40 in the direction of arrow 41. A base ring 10 is accommodated by gun barrel 12 and fastened by means of screws 39. Gun barrel 12 additionally includes a thread 42 on its exterior for fastening breech ring 40, and a recess 46 in the interior at the rear end of a charge chamber 44 for accommodating base ring 10.
FIG. 2 shows breechblock 20 in the closed position in which a breechblock insert 21 constitutes the contact surface of an angular obturating ring 16 seated in a recess 14 of base ring 10. Obturating ring 16 has an axially oriented arm 16.1 and a radially oriented arm 16.2. The depth of recess 14 in base ring 10 is less than the length of axially oriented arm 16.1 so that a play of 0.1 mm to 0.2 mm can be set between arm 16.2 of obturating ring 16 extending radially to gun barrel 12 and breechblock insert 21 in order to permit transverse movement of the breechblock wedge by displacement of base ring 10 in the axial direction 47. In the loading position (not shown), a loading channel 50 in breechblock 20 is disposed behind obturating ring 16 so that the ammunition (not shown), that is, projectiles and propelling charges, can be transported into charge chamber 44.
In order for arms 16.1 and 16.2 of obturating ring 16 to be charged with gas pressure for sealing immediately after a shot is fired, recess 14 is connected with charge chamber 44 by means of a plurality of bores 48. On the side of the charge chamber, base ring 10 ends in a narrow obturating lip 11 which lies against the interior of the gun barrel.
As means for adjusting the required axial play between the radial arm 16.2 of obturating ring 16 and breechblock 20 or breechblock insert 21, a threaded ring 18 is disposed within an annular groove 22 facing gun barrel 12 and disposed within base ring 10.
FIGS. 3 to 8 show that the surfaces of the interior bore 24 and of the exterior face 26 of threaded ring 18, and the associated axially extending faces 28 and 30 of annular groove 22 disposed in base ring 10, each are provided with a thread having the same pitch and the same starting point. Due to the fact that threaded ring 18 is provided with threads on both its inner and outer sides, threaded ring 18 becomes highly stressable and is supported without tilting. In particular, the forces acting forwardly onto base ring 10 and to be transferred to the gun barrel can be reliably absorbed by threaded ring 18.
By configuring the interior and exterior threads of threaded ring 18 and annular groove 22 as a fine thread having a pitch in a range between 0.6 mm and 1.5 mm, the required axial play of 0.1 mm to 0.2 mm can be set very precisely and easily between obturating ring and breechblock 20 or breechblock insert 21.
On its circumference, threaded ring 18 is provided with adjustment means 32 for fixing the set play and simultaneously securing threaded ring 18 against rotation. Adjustment means 32 are composed of radially extending grooves 34 disposed in the exterior circumferential surface of threaded ring 18 and which open outwardly in the shape of the letter U. Alternatively, in a manner not shown, adjustment means 32 may be provided in the form of bores. A securing pin 36 screwed into base ring 10 engages in at least one groove or bore 34 and, after adjustment of the axial play, is screwed into the free space of groove or bore 34 to secure the setting of threaded ring 18.
In the illustrated embodiment, adjustment grooves 34 are uniformly distributed over the circumference 12 of threaded ring 18. In one embodiment of threaded ring 18 in which it has a fine thread, for example with a pitch of 1.5 mm, an adjustment step of 0.12 mm can be realized and for a fine thread having a pitch of 0.6 mm an adjustment step of 0.05 mm can be realized with a rotation of the threaded ring between one groove 34 and the next. By increasing the number of adjustment grooves 34 on threaded ring 18, the setting accuracy for adjustment of the ring can be made even more precise. Thus, with 24 grooves and a pitch of 0.6 mm, it is possible to realize adjustment accuracies of 0.03 mm, and for a pitch of 1.5 mm, adjustment accuracies of 0.06 mm can be realized. With a fine clockwise thread, the distance from gun barrel 12 decreases when threaded ring 18 is turned clockwise so that the play to be set between obturating ring 16 and the breechblock becomes greater. For rotation in the opposite direction, the play to be set becomes correspondingly smaller.
In order to ensure a secure force transmission, threaded ring 18 has such a thickness that at least four supporting thread turns are screwed into annular groove 22.
The fine thread disposed on faces 28 and 30 within annular groove 22 ends in a groove enlargement 23 whose corners are rounded in order to reduce a notch effect.
Threaded ring 18 can still be adjusted with ease even after longer periods of use because its arrangement is protected against powder gases by sealing lip 11 and obturating ring 16.
In order to ensure that ring 18 is screwed uniformly into annular groove 22, the respective interior and exterior fine threads of ring 18 begin at the same point 25 and the fine threads disposed on faces 28 and 30 of annular groove 22 also begin at the same point 27.
As shown in FIGS. 1, 3 and 4, base ring 10 can easily be released from recess 46 of gun barrel 12 by preferably three thrust screws 38 distributed over the circumference. Thrust screws 38 require no further passage through threaded ring 18 for the thrusting process because the free space of grooves 34 can be utilized to advantage for this purpose.
Obviously, numerous and additional modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically claimed. | An arrangement for axially adjusting play between an obturating ring of a gun barrel base ring and a wedge-type breechblock. The base ring has a threaded ring adjustably disposed in an annular groove adjacent the gun barrel for adjusting axial play existing between the obturating ring and the wedge-type breechblock. | 5 |
FIELD OF THE INVENTION
This invention relates to error correction of a received data stream and more particularly to an error correction method and system which employs ambiguity zone detection, permutation and inverse permutation and iterative processing to perform the error correction action.
BACKGROUND OF THE ART
A primary objective of any digital communication system is to transmit information at the maximum possible rate and receive it with minimum errors or distortion. Similarly, a main design objective of data storage system is to allow the system to store information with the maximum possible density and to retrieve it with the least possible errors. A variety of error control coding schemes, channels with constraint, and digital modulation with constraint have been devised to improve data transmission and recording systems.
CONCATENATED ENCODING AND DECODING SYSTEMS
Error control codes such as block codes and convolutional codes are usually applied to digital sequences for the purpose of coping with errors which may happen in bursts as well as randomly. Basically, error control coding expands the information sequence by adding additional bits for error correction/detection purposes. The encoded sequence then contains some constraint or redundancy. Such constraint is then exploited by the receiver to identify possible errors that may exist in the received sequence. For example, if the received sequence does not satisfy parity-check equations, then the receiver detects the existence of some errors and, in some cases, can correct them.
In order to achieve a higher performance, a concatenation of two error correcting codes is sometimes adopted. FIG. 1 depicts such a concatenated encoding system and the corresponding decoding system. Here the term "inner encoder" is used in the sense that the inner encoder is closer to the communication channel. Hence a subsystem including an inner encoder, the communication channel and an inner decoder, is often called an "outer channel". The outer encoder therefore sees the outer channel as the effective channel.
An example is to use a block code (e.g., a Reed-Solomon code) as the outer code and a convolutional code as the inner code. An "interleaver" is often placed between the two encoders, because when the inner decoder makes erroneous decisions, it tends to create bursts of errors due to the nature of the convolutional code. FIG. 2 depicts such a concatenated system. An interleaver is an example of a device which permutes a data stream in a manner which is reversible. An example of an interleaver is shown in FIG. 2a, with bits 0-63 being serially loaded into adjacent rows. An output is obtained by sequentially accessing adjacent columns of bits. The interleaving action disperses adjacent bit values and prevents a burst error from affecting a sequential run of bits in the original data stream.
By having the interleaver in front of the outer channel, the outer encoder and decoder do not have to deal with long bursts of errors. (See e.g., S. Lin and D. J. Costello, Jr., Error Control Coding:Fundamentals and Applications, Prentice-Hall, 1983. pp. 535-538.) The type of system represented in FIG. 2 is closely related to the invention to be described below, in that a receiver incorporating the invention can be applied to the illustrated class systems without changing the transmitter side hence, as will be seen, the invention is backward compatible with such existing systems.
CHANNELS WITH CONSTRAINT
The notion of concatenated system can be generalized to a system in which the inner encoder is not a conventional error correcting encoder (such as a block code or convolutional code), but is a special type of signaling scheme or a channel with some constraint or memory. (See e.g., H. Kobayashi, "A Survey of Coding Schemes for Transmission or Recording of Digital Data", IEEE Trans. Communication Technology, vol. COM-19, pp. 1087-1100, December 1971).
Intersymbol interference (ISI) and/or interchannel interference (ICI) due to channel distortion, may sometimes be predominant factors in limiting performance and reliability. A number of coding techniques have been developed to reduce adverse effects due to these factors. Partial-response channel coding is well recognized as a bandwidth-efficient transmission technique and can be viewed as a technique to shape the signal spectrum by introducing a controlled amount of ISI. An optimal decoding structure for a partial-response channel is known as maximum-likelihood (ML) decoding (See e.g., H. Kobayashi, "Application of Probabilistic Decoding to Magnetic Recording Systems", IBM J. of Res. and Develop. Vol. 15, Jan. 1971, pp. 64-74., and H. Kobayashi, "Correlative Level Coding and Maximum-Likelihood Decoding", IEEE Trans. Information Theory, Vol. IT-17, Sep. 1971, pp. 586-594.).
A system with partial-response channel coding and maximum likelihood decoding has become popular in recent years and is often referred to as a PRML system (see e.g., J. W. M. Bergmans, "Digital Baseband Transmission and Recording", Kluwer Academic Publishers, 1996).
Another class of codes, often used in digital recording, is run-length limited codes, denoted (d,k)-limited codes. The integer parameters d and k represent the minimum and maximum numbers of runs of either 0's or 1's that are allowed in the encoded sequence. The lower bound d is chosen from the ISI consideration, and the upper bound k is set to insure clock synchronization capability at the receiver side.
Both partial-response channels and run-length limited codes can be viewed as techniques that introduce some constraints into the digital sequence to be transmitted. Similarly, a channel with ISI and/or multipath fading introduces some memory in the received sequence. Such constraints or memory should be exploited by the receiver to identify possible errors or biases that may exist in the received sequence. FIG. 3 shows a generalized concatenated system where the inner encoder represents a channel with some constraint.
DIGITAL MODULATION WITH CONSTRAINT
Techniques similar to partial-response signaling have been developed in digital modulation schemes. One important class of such modulation techniques is known as continuous phase modulation (CPM) or continuous envelope coded modulation (see e.g., C. E. Sundberg, "Continuous Phase Modulation", IEEE Communications Magazine, April 1986, pp. 25-38). Here, some constraint is introduced in the modulated signal, because the phase values that the modulated signal is allowed to take are limited to a subset of the set of phase values defined for the modulation system. An example of CPM is MSK (minimum shift keying) in which the phases that the modulated signal is permitted to take at a given symbol time are only the phases adjacent to the previous symbol phase.
Another class of digital phase modulation techniques with similar properties is those that use differential precoding of the data. In this case, the correlation is caused by the preceding and consequent modulation. An example of differentially precoded digital phase modulation is π/4-QDPSK (π/4-shifted quadrature differential phase shift keying).
These modulation techniques can be viewed as a means to minimize the adverse effects of unknown/time-varying channel attenuation, fading and nonlinear power amplification, while still allowing bandwidth efficient communication. Since the amplitude of transmitted signals contains no information, one can reproduce the original information even if the amplitude has been significantly distorted. These classes of digital modulation techniques have come to be predominantly used in wireless communication systems. FIG. 4 depicts a concatenated system in which the inner encoder is a modulator with some constraint.
CODED MODULATION
Instead of concatenating two error control codes, an error control code may be concatenated with digital modulation. A trellis-coded modulation (TCM) is a well-known example in which a convolutional code and digital-phase modulation are combined. The receiver can correct most errors effectively, since the receiver can exploit the constraint that the received phase sequence must satisfy. This is because a particular method (called set partitioning) is used to map the convolutional code sequence into the amplitudes and/or phases of the modulated signal. A concatenated system with TCM is schematically shown in FIG. 5.
An optimal decoding structure for continuous phase modulation, precoded digital phase modulation and TCM is maximum-likelihood (ML) decoding, similar to that originally derived for convolutional codes (i.e., Viterbi decoding) and for partial-response systems.
ERASURES
A receiver may be designed to decide that a symbol should be erased when it is received ambiguously. Suppose that a channel input is binary, i.e., 0 or 1. When a received symbol is corrupted by strong noise or interference and its value is near the threshold between 0 and 1, then the receiver may opt not to make a hard decision regarding the value of the symbol, and labels it as "e", which stands for an erasure. To implement an erasure, a quantizer is required with additional threshold(s), see FIG. 6a). When the input is binary, the output with erasure option can be represented by two bits, e.g., by (00), (01) and (10) to denote "0", "e" and "1", respectively.
A In coding theory a binary erasure channel (BEC) has been well studied (see e.g., W. W. Peterson and E. J. Weldon, Jr., "Error Correcting Codes", 2nd Edition, MIT Press, 1994. p. 8). The channel characteristic of a BEC is shown in FIG. 6b, where the possible errors are limited to erased digits. In other words 0 is never mistaken as 1 and vice versa. Kobayashi and Tang, "On Decoding of Correlative Level Coding Systems with Ambiguity Zone", IEEE Trans. Communications, Vol. COM-19, pp. 467-477, Aug. 1971) generalized the erasure concept and applied it to partial-response systems. They showed that decoding with the generalized erasure, which they termed ambiguity zone decoding can achieve a near-optimum performance, while retaining decoding complexity at a minimal level.
As discussed above, a large class of digital communication or recording systems can be viewed as concatenated systems in which each building block may be an error control encoder, a modulator with constraints, or a channel with constraints. The conventional method of receiving such signals is to perform the inverse operations of the transmitter's building blocks, in the reverse order. In other words, building blocks at the receiver are an inner decoder, a de-interleaver and an outer decoder. The inner decoder attempts to do its best in correcting errors and delivers the resultant output to the outer decoder. Such a decoding procedure may be called a "one-path" decoding method. Such a one-path method is still susceptible to being unable to correct many error states, notwithstanding a general ability to correct for many error conditions.
Accordingly, it is an object of the invention to improve error correction performance of a receiver system which receives digital data over a noisy communication channel (e.g., radio channel, cable channel).
It is another object of the invention to improve error correction performance of a system which retrieves data from a memory (e.g., digital magnetic recording disk) which is subject to random/burst noise or medium defects.
SUMMARY OF THE INVENTION
A method error corrects a received data stream in a general concatenated system in which a plurality of encoding algorithms and/or entities which impose a constraint are connected either in series or in parallel or both. The method includes the steps of: (a) sampling signal levels in the received data stream and assigning discrete data values to sampled signal levels falling in non-ambiguous amplitude and/or phase ranges and assigning ambiguity values to sampled signal levels falling within an ambiguity range of amplitude and/or phase values, and outputting a quantized data stream comprising the discrete data values and ambiguity values; (b) decoding and error correcting data values making up the quantized data stream to create an error-corrected data stream, the decoding including plural decoding actions for decoding data that has been encoded or subjected to a constraint by the plural concatenated entities; c) correcting data values and ambiguity values in the quantized data stream by substitution of corrected data values from the error corrected data stream into corresponding data values in the quantized data stream, to thereby create a revised data stream; and d) iteratively subjecting the revised data stream, both as is and as further revised, to steps b) and c) to improve an error correction state of the revised data stream. In a preferred embodiment, the data making up the received data stream has been subjected to a permutation action to time-wise separate original contiguous data values. The method subjects the quantized data stream to an inverse permutation action in producing the error-corrected data stream and further re-permutes the error-corrected data stream (in step (c)) to return it to a format identical to that of the quantized data stream before the substitution is performed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a prior art concatenated system for decoding and error correcting a received data stream.
FIG. 2 is a block diagram of a transmitter and receiver in a concatenated system, with interleaving, for decoding and error correcting a received data stream.
FIG. 2a is a schematic which illustrates an interleaving process.
FIG. 3 is a block diagram of a concatenated system for decoding and error correcting a received data stream, wherein the inner encoder is a channel with constraint.
FIG. 4 is a block diagram of a concatenated system for decoding and error correcting a received data stream, wherein the inner encoder is a modulator with constraint.
FIG. 5 is a block diagram of a concatenated system for decoding and error correcting a received data stream, wherein the inner encoder is a trellis-coded modulator (TCM).
FIG. 6a is a block diagram of a prior art erasure channel.
FIG. 6b is a channel transition diagram of the prior art erasure channel.
FIG. 7a is a block diagram of a transmitter portion of a concatenated system for decoding and error correcting a received data stream, which systemincorporates the invention hereof.
FIG. 7b is a block diagram of a receiver portion of a concatenated system for decoding and error correcting a received data stream, which system incorporates the invention hereof.
FIG. 8 is a block diagram of the concatenated system of FIGS. 7a and 7b, which system incorporates a Hamming code and duobinary signalling.
FIG. 9a is a plot of input/output relationship of a quantizer for duobinary signals, in a prior art threshold detector.
FIG. 9b is a plot of input/output relationship of a quantizer for duobinary signals, in a prior art ambiguity zone detector.
FIGS. 10a and 10b are charts which illustrate four phase modulation with four ambiguity zones (FIG. 10a) and with eight ambiguity zones (FIG. 10b).
FIG. 11a is a block diagram of a concatenated system incorporating the invention which employs three encoders.
FIG. 11b is a block diagram of a concatenated system equivalent to that shown in FIG. 11a which employs two encoders.
FIG. 11c is a block diagram of a concatenated system employing an iterative encoder for the equivalent two encoder system of FIG. 11b.
FIG. 11d is a block diagram of a concatenated system employing an expanded encoder for the three encoder system of FIG. 11a.
FIG. 12a is a block diagram of a concatenated system employing an equivalent two encoder system for the three encoder system of FIG. 11a.
FIG. 12b is a block diagram of a concatenated system employing an iterative decoder for the equivalent two encoder system of FIG. 12a.
FIG. 12c is a block diagram of a concatenated system employing an expanded decoder for the three encoder system of FIG. 11a.
FIG. 13 is a block diagram of a concatenated system employing an iterative three decoder system for the three encoder system of FIG. 11a, with one feedback loop.
FIG. 14a is a block diagram of a two-parallel concatenated system incorporating the invention.
FIG. 14b is a block diagram of an iterative decoder for the two-parallel concatenated system of FIG. 14a.
DETAILED DESCRIPTION OF THE INVENTION
Iterative Decoding with Ambiguity Zone Detection (AZD) and Permutation
A system incorporating the invention is schematically shown in FIG. 7. The transmitter side is almost the same as any of the concatenated systems discussed above, except that a "permutation" module has been inserted, for generalization purposes, (instead of the interleaver) between the outer and inner encoders. A carefully designed permutation module can improve the system more than a conventional interleaver, however it is to be understood that an interleaver is within the ambit of a permutation module and is a special and simple type of permutation module. Similarly, a concatenated system without an interleaver (FIG. 1) also can embody the invention, as no interleaver is equivalent to insertion of an "identity permutation". Thus, the invention can be applied to a large class of systems with little or no modification at the transmitter side.
The invention places an AZD (ambiguity zone detector) 10 at the receiver front end 12. An AZD is a threshold detector (or quantizer) which assigns "erasure symbols" to those digits that fall in ambiguous zones (see the example described below). The output sequence from AZD 10 is then processed by passing it to concatenated decoders 14 an 16 which are connected in a loop. Between decoders 14 and 16 is an inverse permutation module 18 (in the forward path) and a permutation module 20 (in the feedback path). Permutation module 20 is identical to the permutation module used at the transmitter.
Thus, in a first iteration after receiving a data stream, the output sequence from AZD 14 is processed by inner decoder 14, inverse permutation module 18 (which reverses the permutation inserted at the transmitter) and outer decoder 16. The decoded (and error-corrected) data stream is then processed by permutation module 20 which re-permutes the data stream to the form it had upon arrival at receiver input 12. At the end of a first iteration, the original output sequence from AZD 10 is modified by an error/erasure corrector 22, which incorporates the corrections made in the first pass through the forward path. The second iteration applies the modified AZD output to the above-mentioned receiver blocks, in the same order as in the first iteration. The cyclical decoding procedure repeats.
At each iteration, some of the remaining errors/erasures will be resolved, and error/erasure corrector module 22 modifies the AZD output sequence, by use of a simple logic circuit (or logic table) which substitutes some digits of the AZD sequence with their corrected values. In the first iteration, the error/erasure corrector module 22 plays no role, since the feedback loop provides no information at such time. The iterative procedure ends when all erasures are resolved and no errors are detected, or when no new resolution of error/erasures are achieved, or after a prescribed number of steps (as determined by logic block 24).
At this point there are two options if the decoded sequence contains some unresolved erasures or detectable errors: (1) the receiver can reject the received sequence and ask the transmitter for a retransmission, or (2) the receiver can make "hard" decisions on these digits and deliver the decoded result to data sink 26. This cyclic decoding procedure is hereafter referred to as iterative decoding.
If the channel contains burst errors, the original AZD output will contain errors/erasures in clusters, hence the provision of a permutation module or interleaver module is helpful in enabling correction of some such error conditions. However, even if the channel errors are random, i.e., not bursty, errors/erasures that remain unresolved after a few decoding cycles tend to form clusters. This is because isolated errors/erasures will be the first ones to disappear, and the remaining errors are likely to be the ones that appear in a bunch. The permutation and inverse-permutation in the decoding loop will separate these digits apart, hence the decoders in the next cycle stage can then resolve these isolated errors/erasures.
An Illustrative Example of the Invention
It is easiest to explain the invention by way of an example. A concatenated system of the type shown in FIG. 3 is shown in further detail in FIG. 8 which illustrates both the transmission and reception sides. As the outer code, a (7, 4) Hamming code is used and the inner code is duobinary signaling with a precoder. An (n, k) Hamming code is a single error correcting code, which can correct any single error that may exist in a block of bits, consisting of message bits, and parity-check bits (see e.g., Lin/Costello or Peterson/Weldon for details on Hamming codes).
Duobinary signaling is often achieved by sending a binary pulse sequence at a faster rate than is possible in ordinary transmission (see e.g., Bergmans, or any of the aforementioned articles by Kobayashi). When the channel input is binary (0 or 1), then the channel output, sampled at an appropriate rate, should be equivalent to the sum of the present and preceding digits. Thus, the output sequence is a three-level sequence, i.e., 0, 1, or 2. This three-level sequence cannot take on these values independently, because of the nature of its construction. For example, the output sequence should not have direct transitions from 0 to 2 or vice versa. The resultant ternary sequence, called duobinary, is a sequence with some correlation property due to the channel bandwidth constraint.
The precoder introduces a simple transformation prior to the transmission by duobinary signaling. Its purpose is to prevent a possible error propagation in the decoded output. The precoder maps the input binary sequence into another binary sequence, based on the following rule: when the current input is 0, the output should remain in the previous value; and when the input is 1, the output changes its value from the previous one, i.e. either 0 to 1 or from 1 to 0. Precoding of a binary sequence is similar to differential encoding usually used in DPSK (differential phase shift keying). Precoding for multi-level sequences is described in D. T. Tang and H. Kobayashi, "Error-Detecting Techniques for Multilevel Precoded Transmission", U.S. Pat. No. 3,622,986. Duobinary signaling illustrated in this example is a simplest case of partial-response channel coding referred to in the Background of the Art.
Consider a simple packet transmission system in which there are 28 information bits in a packet, an example of which is given by the stream:
I.sub.1 =(0001001000110100010101100000)
Rather than encoding the entire packet at once, it is first segmented into blocks of k=4 bits, and each block is then encoded to a codeword of length n=7, by using a (7, 4) Hamming code. Its parity-check and generator matrices are given in systematic form by:
______________________________________ 1 0 1 1 1 0 0 H = 1 1 1 0 0 1 0 0 1 1 1 0 0 1and 1 0 0 0 1 1 0 G = 0 1 0 0 0 1 1 0 0 1 0 1 1 1 0 0 0 1 1 0 1______________________________________
Then the Hamming encoder output is the following 49 bits (commas are placed between code words for clarity):
I.sub.2 =(0001101, 0010111, 0011010, 0100011, 0101110, 0110100, 0000000)
To perform a permutation action, a 7×7 block interleaver (e.g.,see FIG. 2b) is used which will store the above 49 bits row-wise in the following array structure.
______________________________________ 0 0 0 1 1 0 1 0 0 1 0 1 1 1 0 0 1 1 0 1 0 = 0 1 0 0 0 1 1 0 1 0 1 1 1 0 0 1 1 0 1 0 0 0 0 0 0 0 0 0______________________________________
Then the permutation output is obtained by reading out the above array, column by column as follows:
I.sub.3 =(0000000, 0001110, 0110010, 1010100, 1100110, 0111100, 1101000).
The precoder output is obtained by taking the modulo-2 sum of the current input and the previous output (where "modulo-2 summation" can be implemented by Exclusive OR: 0+0=0, 0+1=1, 1+0=1, 1+1=0 ):
I.sub.4 =(0000000, 0001011, 1011100, 1100111, 0111011, 1010111, 011000)
A duobinary sequence which might be observed at the channel output, in the absence of noise, may be given by
I.sub.5 =(0000000, 0001112, 2112210, 1210122, 1122112, 2111122, 1121000)
Because of channel noise or interference, a received (and sampled) sequence will deviate from the sequence I 5 . This noisy sequence is passed into an ambiguity zone detector (AZD), whose input and output relation is shown in FIG. 9b, in contrast with an ordinary threshold detector shown in FIG. 9a. When the noise is large, the received sequence may fall in ambiguity zones E or F. The AZD outputs are labeled as e or f, respectively. The symbols e and f are called "generalized erasures". The AZD output, therefore, has five levels {0, e, 1, f, 2}. In actual implementation, these values may be represented by {0, 0.5, 1, 1.5, 2} or a three bit representation may be used, e.g., {(000), (001), (010), (011), (100)}, or any similar representation.
In general, an AZD increases the quantization level by L-1, where L is the number of legitimate channel output levels (e.g., L=3 in the duobinary signal). This modest increase in the quantization level (hence one or a few additional bits required per digit) is advantageous to the conventional "soft-decision" quantizer which represents the received sequence in several-to-many bits per digit.
Suppose that the AZD output is given by:
I.sub.6 =(00e00ee, 00ee112, f11ff10, 1ffe122, 1eff112, 21ef122, ff21e00).
For simplicity it is assumed that no errors are made by the AZD processing. In other words, the ambiguity zones are set wide enough to capture all the noisy data. The invention is applicable to cases where the AZD output may contain errors as well as erasures. Existence of errors in the AZD output does not affect the principle of the iterative decoding procedure. It is simply a matter of added complexity in the decoder implementation.
The above AZD output is then fed to the decoder that attempts to resolve as many erasures/errors as possible. A "generalized maximum likelihood decoder" (MLD) is used in this example. An MLD for a partial-response channel is described in the aforementioned articles by H. Kobayashi, and is now widely known as a PRML (partial-response, maximum-likelihood) decoder (see e.g., Bergmans). The generalized MLD accepts a five-valued AZD sequence and produces also a five-value sequence, although the latter contains fewer e's and f's. This contrasts with a conventional MLD (often called a Viterbi decoder) that produces a 0-1 sequence at the decoder output in the one-path decoding algorithm.
In the present case, the generalized MLD can correct all isolated erasures and some consecutive erasures as shown below.
I.sub.7 =(00000ee, 0001112, f11ff10, 1ffe122, 1eff112, 2111122, ff21000,
where the digits obtained by resolving erasures are shown in bold face.
A mod-2 operation is then applied to the above sequence, whereby any 2 is replaced by 0 (i.e., 2=0 modulo 2). The erasures e and f are retained. Hence, the resultant sequence takes four value {0, e, 1, f} which can now be represented in two bits instead of three bits, if necessary.
I.sub.8 =(00000ee, 0001110, f11ff10, 1ffe100, 1eff110, 0111100, ff01000),
The generalized MLD and the mod-2 decoder can be combined in an actual implementation, producing I 8 directly from I 6 . The MLD and the mod-2 decoder are shown separately in order to clarify the decoding step.
Next, an inverse permutation (i.e., 7×7 de-interleaver) is applied. This can be performed in the same manner as the interleaving is performed at the transmitter. The only difference is that the data is written-in vertically, and is read-out horizontally:
______________________________________ 0 0 f 1 1 0 f 0 0 1 f e 1 f 0 0 1 f f 1 0.sup.-1 = 0 1 f e f 1 1 0 1 f 1 1 1 0 e 1 1 0 1 0 0 e 0 0 0 0 0 0______________________________________
The output of the de-interleaver is therefore given by
I.sub.9 =(00f110f, 001felf, 001ff10, 01fef11, 01f1110, e110100, e000000).
The above sequence is then passed into a "generalized Hamming decoder". The decoder receives the input with erasures, and corrects some errors and/or resolve some erasures. It is different from the ordinary Hamming decoder in the sense that the unresolved erasures are retained for further processing. Similarly unlike a conventional decoder, the check (i.e., parity) bits are not thrown away until the iterations are completed.
The generalized Hamming decoder can be constructed by modifying a "syndrome-based decoder" (see e.g., Lin/Costello, Peterson/Weldon for the conventional syndrome-based decoder), or by creating a decoding table. For this example, a majority of remaining errors and erasures contained in I9 can be corrected, obtaining
I.sub.10 =(0001101, 001felf, 0011010, 1100011, 0101110, 0110100, 0000000)
At the end of the first iteration, a permutation action is performed. This can be done by writing the seven blocks of I 10 row-wise, and creating the following array:
______________________________________ 0 0 0 1 1 0 1 0 0 1 f e 1 f 0 0 1 1 0 1 0' = 0 1 0 0 0 1 1 0 1 0 1 1 1 0 0 1 1 0 1 0 0 0 0 0 0 0 0 0______________________________________
The permutation output is obtained by reading out the above array column by column, yielding:
I.sub.11 =(0000000, 0001110, 0110010, 1f10100, 1e00110, 0111100, 1f01000)
Note that the array π' can share the memory space (or registers) used by the array π -1 , since the contents of these arrays are not retained once they are read out.
The error/erasure corrector module compares the original AZD output I 6 and the above I 11 , and replace some of the errors/erasures in I 6 by their correct values, yielding I 12 shown below.
I.sub.12 =(0000000, 0001112, 2112210, 1f10122, 1e22112, 2111122, 1f21000).
Note that the string I 11 is a binary sequence, whereas I 12 , like I 6 is a duobinary sequence with some erasures. So if some digit in I 11 is 0 (i.e., just corrected in the latest iteration), then the corresponding e in I 12 should be replaced by 0, and f by 1. Similarly, if some digit in I 11 is 1, then the corresponding erasure (whether e or f ) in I 12 should be changed to 1.
The second iteration of decoding starts with the sequence I 12 , which contains fewer errors/erasures than the original AZD output I 6 . This will make the subsequent decoding task simpler, hence will help the second iteration to further reduce the remaining errors/erasures. With 12 as the new input, the generalized MLD can correct, in this particular instance, all the remaining erasures, obtaining
I.sub.13 =(0000000, 0001112, 2112210, 1210122, 1122112, 2111122, 1121000).
Then a mod-2 operation is applied to I 13 (as was done to I 7 in the first iteration), obtaining
I.sub.14 =(0000000, 0001110, 0110010, 1010100, 1100110, 0111100, 1101000),
which is the same as I 3 .
Next, the 49 bits are written into the de-interleaver array column-wise:
______________________________________ 0 0 0 1 1 0 1 0 0 1 0 1 1 1 0 0 1 1 0 1 1.sup.-1 = 0 1 0 0 0 1 1 0 1 0 1 1 1 0 0 1 1 0 1 0 0 0 0 0 0 0 0 0______________________________________
The bits are then read out row-wise, to obtain a binary sequence:
I.sub.15 =(0001101, 0010111, 0011010, 0100011, 0101110, 0110100, 0000000)
which is identical to I 2 , as it should be. Therefore, all the erasures have been resolved even before the second iteration is completed.
The Hamming decoder checks the above sequence, block-by-block (by either "syndrome calculations" or by "table look-up"), and confirms that there are no errors. By deleting the last 3 bits (parity-check bits) in each block of 7 bits, the final decoded output is obtained:
I.sub.16 =(0001, 0010, 0010, 0100, 0101, 0110, 0000)
Hence the iterative decoder has successfully recovered the original information sequence of length 28 bits, and delivers it to the data sink or the end user. Should AZD output I 6 start with more erasures/errors, it would take more than two iterations to complete.
In the above description it has been assumed that the information source is binary data. The invention can also be applied to a non-binary system. For instance, a Reed-Solomon code can be used as an error correcting code instead of Hamming or BCH codes.
Partial-response channel coding can be also employ multi-level signals, as discussed in the aforementioned US patent by Tang/Kobayashi. Use of QAM (quadrature amplitude modulation), PSK (phase shift keying) or MSK (minimum shift keying) creates an equivalent baseband system with non-binary symbols.
In the above description, an ambiguity zone between adjacent legitimate values was considered. If the information is in L possible amplitudes of received sequence (as in the partial-response system), the number of ambiguity zones (hence the number of distinct erasure symbols) is L-1. In case of a phase modulation system with L discrete phase values, then the number of ambiguity zones is also L. FIG. 10a shows an example of 4-phase modulation, where φ1, φ2, φ3 and φ4 show legitimate phases. Regions D 1 , D 2 , D 3 and D 4 are decision regions for these phase values, and regions R 12 , R 23 , R 34 and R 41 are ambiguity zones to be used by the AZD. A signal value that falls in any of these zones will be labeled by one of the erasure symbols, say e 12 , e 23 , e 34 or e 41 . When the modulation scheme combines both amplitude and phase, then partitioning of the signal space into decision regions and ambiguity zones can be defined appropriately in the two-dimensional signal space.
More than one ambiguity zone can be assigned between a pair of legitimate values. For instance FIG. 10b shows a case where the ambiguity zones are subdivided into eight, R 1 +, R 2 -, R 2 +, . . . , R 4 +, R 1 -. This finer ambiguity zone assignment is especially useful when a concatenated system is considered with more than two encoders, as described below.
In the example presented, the result of a previous iteration is reflected by upgrading the AZD output sequence at the "error/erasure corrector". This simple comparison and substitution digit-by-digit is possible for the partial-response system, since a correctly decoded bit affects only one AZD digit position, due to the precoder's property. When the precoder is not adopted, or an appropriate precoder does not exist, as for a convolutional code, the "error/erasure corrector" function is incorporated into the inner decoder. In other words, the correctly decoded bit should be used to improve the inner decoder operation, instead of improving its input sequence. This improvement is possible, because the correct bit information made available will help the decoder select a correct "surviving path" among many contenders, in maximum likelihood decoding.
In the discussion above, only concatenated systems with two encoders have been discussed (i.e., the inner and outer encoders) at the transmitter and the corresponding two decoders at the receiver. The invention can be extended to a concatenated system with three or more encoders. An example of such a concatenation is one which contains a product encoder, followed by a partial-response channel (or a runlength-limited coder), as is often found in a digital storage system. As indicated above, a product code is by itself equivalent to a concatenated code with an interleaver in-between.
Consider, for instance, the concatenated coding system shown in FIG. 11a, where E 1 , E 2 and E 3 are encoders, and π 12 and π 23 are permutations. One way to derive the iterative decoding structure described above is to form a subsystem, which can be termed an "outer encoder" E out , including E 1 , π 12 and E 2 . The remaining subsystem, called an "outer channel" includes π 23 , E 3 and the channel, as shown in FIG. 11b. This system is a two concatenated system where E 3 is the inner encoder and having permutation π 23 between the outer encoder and this inner encoder. This observation readily leads to the iterative decoding system shown in FIG. 11c, where D out is the decoder for the outer encoder E out . Since the E out itself is a two-concatenated system, D out itself is a two-concatenated decoder. Thus, a decoding system is obtained as shown in FIG. 11d. Note that the quantization by AZD 2 may be more coarse than AZD 1 , or AZD 2 may not exist. Such a decision depends on the particular structure of the encoders, and cost/performance tradeoffs of the decoder.
Another way to derive an iterative decoder for the system FIG. 11a is to combine E 2 , π 23 and E 3 to form an inner encoder E in , as shown in FIG. 12a. Such grouping may be appropriate, for example, when E 1 is a block encoder, and E 2 is a convolutional encoder, and E 3 is a modulator with a constraint. Trellis coded modulation (TCM) corresponds to the case where E 2 is a convolutional encoder, E 3 is a phase modulator with constraint, and the permutation π 23 can be included as part of a set-partitioning rule used in TCM.) Then E 1 (an outer encoder by itself) and Bin form a two-concatenated system. The decoder structure of FIG. 11b is then obtained, where D in is the decoder for E in . By applying the similar argument as above, the structure D in , can be expanded, to obtain the overall decoder of FIG. 12c.
In either case the iterative loops are nested. That means in each iteration of an outer loop there will be several iterations along the inner loop.
A third type of decoding scheme is shown in FIG. 13, where a single feedback loop is formed and the erasure/error correction is incorporated in actual decoders D 1 , D 2 and D 3 .
The iterative decoding with AZD procedure described above can be generalized to a case where a parallel concatenation is adopted at the transmitter side. An example of such a system is a new class of codes, called Turbo codes (see e.g., Berroeux, A., "Near Optimum Error Correcting Coding and Decoding: Turbo Codes", IEEE Transactions on Communications, October 1996, pp. 1261-1271). FIG. 14a depicts such a system, where an information sequence I from a source is first passed into two parallel permutations π 1 and π 2 , which are then encoded by encoders E 1 and E 2 . The encoded messages are then multiplexed and sent over a channel.
The corresponding decoder is shown in FIG. 14b. The incoming data stream first passes AZD, and then is demultiplexed to generate two parallel streams. The upper stream is a noisy version of the output of E 1 , and the lower stream is a noisy version of the E 2 output. Iterative decoding is then performed by allowing lower decoder D 2 to use I as an estimate of I generated by upper decoder D 1 . The lower decoder then generates a new (and presumably better) estimate of the information, denoted I, and this will be fed back to the upper decoder. With this new information the upper decoder will produce a better estimate than its previous I. This can be fed again to the lower decoder, and so forth. The iteration steps should end when all erasures are resolved, or no further improvement is achieved.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. | A received signal is first converted into a digital sequence that may contain "erasures" (or ambiguity symbols) as well as errors. Then iterative decoding is applied in order to eliminate or reduce the erasures. This decoding procedure works effectively with the associated transmitter that adopts a concatenation of an outer coder, a permutation and an inner coder. The principal of the invention is also applicable to a system in which the inner coder is replaced by a "digital modulator" that introduces some constraint, or a channel that introduces some memory such as partial response signaling, intersymbol interference or multipath propagation. The invention can be applied to many existing systems while maintaining "backward compatibility" in the sense that the transmitter side need not be modified. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to certain indole alkanoic acids. Such compounds are able to selectively antagonise the effect of thromboxane A 2 (TXA 2 ), and its precursor prostaglandin H 2 (PGH 2 ), at the thromboxane receptor. In addition, certain of the compounds also selectively inhibit the thromboxane synthetase enzyme. The compounds are thus useful as therapeutic agents and they may be used either alone, or, in the case of compounds which do not inhibit the thromboxane synthetase enzyme, preferably in combination with a thromboxane synthetase inhibitor, for example in the treatment of atherosclerosis and unstable angina and for prevention of reocculsion, both acute and chronic, after percutaneous transluminal coronary and femoral angioplasty. The compounds may also find clinical utility in a further variety of disease conditions in which thromboxane A 2 has been implicated such as in the treatment of myocardial infarction, stroke, cardiac arrhythmias, transient isohaemic attack, tumour metastasis, peripheral vascular disease, bronchial asthma, renal disease, cyclosporin-induced neprotoxicity, renal allograft rejection, vascular complications of diabetes and endotoxin shock, trauma, pre-eclampsia and in coronary artery bypass surgery and haemodialysis.
SUMMARY OF THE INVENTION
The compounds of the invention are of formula (I): ##STR2## and pharmaceutically acceptable salts and biolabile esters thereof, wherein R 1 is H, C 1 -C 4 alkyl, phenyl optionally substituted by up to three substituents independently selected from C 1 -C 4 alkyl, C 1 -C 4 alkoxy, halogen and CF 3 , or is 1-imidazolyl, 3-pyridyl or 4-pyridyl;
R 2 is H or C 1 -C 4 alkyl,
R 3 is SO 2 R 4 or COR 4 where R 4 is C 1 -C 6 alkyl, C 1 -C 3 perfluoralkyl(CH 2 ) p , C 3 -C 6 cycloalkyl(CH 2 ) p , aryl(CH 2 ) p or heteroaryl(CH 2 ) p , p being 0, 1 or 2, or R 4 may be NR 5 R 6 where R 5 is H or C 1 -C 4 alkyl and R 6 is C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl or aryl, or R 5 and R 6 together with the nitrogen atom to which they are attached form a 5- to 7-membered heterocyclic ring which may optionally incorporate a carbon-carbon double bond or a further heteroatom linkage selected from O, S, NH, N(C 1 -C 4 alkyl) and N(C 1 -C 5 alkanoyl);
X is CH 2 or a direct link, with the proviso that when R 1 is 1-imidazolyl then X is CH 2 ;
m is 2, or 3;
n is 0, 1 or 2,
and wherein the group (CH 2 ) n NHR 3 is attached at the 5-position when n is 0 or 1, or at the 5- or 4-position when n is 2.
In the above definitions "aryl" means phenyl or naphthyl and "heteroaryl" means furyl, thienyl or pyridyl, any of which ring systems may optionally be substituted with one to three substituents each independently chosen from C 1 -C 4 alkyl, C 1 -C 4 alkoxy, halo, CF 3 , OCF 3 and CN. Alkyl and alkoxy groups having three or more carbon atoms may be straight chain or branched chain. "Halo" means fluoro, chloro, bromo or iodo.
Compounds containing asymmetric centres can exist as enantiomers and diastereisomers, and the invention includes the separated individual isomers as well as mixtures of isomers.
Also included in the invention are radiolabelled derivatives of compounds of formula (I) which are suitable for biological studies.
The term biolabile ester in the above definition means a pharmaceutically acceptable, biologically degradable ester derivative of a compound of formula (I), that is a prodrug which, upon administration to an animal or human being, is converted in the body to a compound of formula (I). In the case of the compounds of formula (I), such biolabile ester prodrugs are particularly advantageous in providing compounds of formula (I) suitable for oral administration. The suitability of any particular ester-forming group can be assessed by conventional in vivo animal or in vitro enzyme hydrolysis studies. Thus desirably, for optimum effect, the ester should only be hydrolysed after absorption is complete. Accordingly, the ester should be resistant to premature hydrolysis by digestive enzymes before absorption, but should be productively hydrolysed by, for example, gut-wall, plasma or liver enzymes. In this way, the active acid is released into the bloodstream following oral absorption of the prodrug.
Suitable biolabile esters may include alkyl, alkanoyloxyalkyl, cycloalkanoyloxyalkyl aroyloxyalkyl and alkoxycarbonyloxyalkyl esters, including cycloalkyl and aryl substituted derivatives thereof, aryl esters and cycloalkyl esters, wherein said alkyl, alkanoyl or alkoxy groups may contain from 1 to 8 carbon atoms and be branched-chain or straight-chain, said cycloalkyl groups may contain from 3-7 carbon atoms and said cycloalkyl groups may contain from 3-7 carbon atoms wherein both are optionally benzo-fused, and said aryl and aroyl groups include substituted phenyl, naphthyl or indanyl ring systems. Preferably, the biolabile esters of the invention are C 1 -C 4 alkyl esters. More preferably, they are methyl, ethyl and t-butyl esters.
The pharmaceutically acceptable salts of the compounds of formula (I) are those formed with bases which provide non-toxic salts. Examples include the alkali and alkaline earth metal salts such as the sodium potassium or calcium salts, and salts with amines such as diethylamine.
A preferred group of compounds of formula (I) is that where R 1 is optionally substituted phenyl or pyridyl, R 2 is H, R 3 is SO 2 R 4 where R 4 is optionally substituted phenyl, X is CH 2 , m is 2, n is 0 or 2, and (CH 2 ) n NHR 3 is attached at the 5-position.
Another preferred group of compounds of formula (I) is that where R 1 is pyridyl, R 2 is H, R 3 is SO 2 R 4 where R 4 is optionally substituted phenyl or, R 3 is COR 4 where R 4 is alkyl, X is CH 2 , m is 2, n is 2 and (CH 2 ) n NHR 3 is attached at the 4-position.
Particularly preferred are such compounds wherein R 1 is 4-fluorophenyl, R 2 is H, R 3 is 4-arylsulphonyl, X is CH 2 , m is 2, n is 0 and (CH 2 ) n NHR 3 is attached at the 5-position, or wherein R 1 is pyridyl, R 2 is H, R 3 is 3-methylbutanoyl, X is CH 2 , m is 2, n is 2 and (CH 2 ) n NHR 3 is attached at the 4-position.
DETAILED DESCRIPTION OF THE INVENTION
In another aspect the present invention provides processes for the preparation of compounds of formula (I), their biolabile esters and pharmaceutically acceptable salts.
In one process, the compounds of formula (I) are obtained by hydrolysis of their lower alkyl ester precursors of formula (II): ##STR3## wherein R 1 , R 2 , R 3 , m, n, p and X are as defined for formula (I) and R 7 is C 1 -C 4 alkyl, preferably methyl, ethyl or t-butyl. The reaction can be conducted under basic or acidic conditions, e.g. with excess aqueous alkali, preferably sodium hydroxide solution, or excess hydrochloric acid respectively, optionally with a suitable co-solvent such as a C 1 -C 4 alkanol, preferably methanol, at from ambient temperature to the reflux temperature of the reaction medium.
In the case where R 1 ═H and X═CH 2 (i.e. a 3-methylindole), the final compounds may be prepared by hydrogenolysis of the compound where R 1 =1-imidazolyl and X═CH 2 . ##STR4##
The compounds of formula (II) where R 3 is SO 2 R 4 or COR 4 may generally be prepared by sulphonation/sulphamoylation or acylation, respectively of an amine of formula (III): ##STR5## where R 1 , R 2 , R 7 , m, n and X are as defined above. Sulphonylation may be carried out by reaction of the amine of formula (III) with a sulphonyl halide of formula R 4 SO 2 Hal, where Hal is a halogen atom (preferably the chloride), or with a sulphonic anhydride of formula (R 4 SO 2 )O, where R 4 is as defined above but is other than NR 5 R 6 . Sulphamoylation may be carried out similarly by reaction of compound (III) with a sulphamoyl halide (preferably the chloride) of formula R 5 R 6 NSO 2 Hal, to yield a compound of formula (II) in which R 4 is NR 5 R 6 .
Acylation may be carried out by reaction of compound (III) with an acid anhydride of formula (R 4 CO) 2 O or acid halide R 4 CO Hal (preferably the chloride) where R 4 is as defined above.
These reactions may be carried out in the presence of a base such as triethylamine, pyridine, 4-dimethylaminopyridine or combination thereof to act as an acid scavenger in a suitable solvent such as methylene chloride or tetrahydrofuran.
Alternatively, the acylation may be carried out by reaction of compound (III) with an imidazolide of formula ##STR6## generated in situ by reaction of an acid of formula R 4 CO 2 H and carbonyldiimidazole in a solvent such as tetrahydrofuran, dimethylformamide or methylene chloride.
The novel compounds of formula (II) and (III) above are themselves part of the present invention.
The amines of formula (III) may be prepared by different methods, depending on the value of n. When n=2 the amine may be prepared by amine deprotection from a corresponding carbamate of formula (IV): ##STR7## where R 1 , R 2 , R 7 , m and X are as defined above and R 8 is a group which can be selectively removed in the presence of group R 7 to give the required amine. A suitable R 8 group is benzyl, which may be removed by catalytic transfer hydrogenation using ammonium formate and a palladium/carbon catalyst in a suitable solvent such as a methanol/tetrahydrofuran mixture at reflux temperature. Alternatively, this benzyl group may be removed by hydrogenation using hydrogen, at a pressure of 1-5 atmospheres, in the presence of a palladium/carbon catalyst and a solvent such as tetrahydrofuran, methanol or ethanol at a temperature from ambient to 50° C. Another possible R 8 is t-butyl, which may be removed by reaction with an acid such as hydrochloric or trifluoroacetic acid in a solvent such as dichloromethane at a temperature from 0° to 20° C.
When n=1 the amine of formula (III) may be prepared by reduction of a nitrile of formula (V): ##STR8## where R 1 , R 2 , R 7 , X and m are as defined above. This reduction may be performed by hydrogenation in the presence of a metal catalyst such as rhodium/alumina, preferably in the presence of ammonia, or Raney nickel under the usual conditions for this reaction. Reduction may also be carried out by means of diborane.
When n=0 the desired amines of formula (III) may be prepared by reduction of corresponding nitro compounds of formula (VI): ##STR9## where R 1 , R 2 , R 7 , m and X are as defined above. This reduction may be achieved by treatment with hydrogen, typically at a pressure of 1-5 atmospheres, in a suitable solvent such as methanol or ethanol with a catalyst such as palladium/carbon at a temperature of up to 50° C.
The carbamates of formula (IV) may be prepared from carboxylic acids of formula (VII): ##STR10## where R 1 , R 2 , R 7 , X and m are as defined above by reaction with diphenylphosphoryl azide in a suitable solvent, such as dioxan, at reflux in the presence of Et 3 N to form an acyl azide which undergoes the Curtius re-arrangement to give the corresponding isocyanate. Addition of an alcohol, such as benzyl or t-butyl alcohol, gives the corresponding carbamate (IV). Excess alcohol may be used as the solvent in place of dioxan.
The acids of formula (VII) may themselves be prepared from acrylic esters of formula (VIII): ##STR11## where R 1 , R 2 , R 7 , m and X are as defined above and R 8 is a group such as benzyl or t-butyl. Catalytic transfer hydrogenation or conventional hydrogenation, as described above in relation to compounds (IV), reduces the double bond of the acrylic substituent and, when R 9 is benzyl, also removes the R 9 group to yield an acid of formula (VII). When R 9 is a group not removed by hydrogenolysis, such as t-butyl, it may be removed by treatment with a strong acid, such as hydrochloric or trifluoroacetic acid, before or after hydrogenation of the acrylic double bond.
The esters of formula (VIII), nitriles of formula (V) and nitro compounds of formula (VI) may all be prepared from indole compounds of formula (IX): ##STR12## where R 1 , R 2 and X are as defined above and R 10 is ##STR13## CN or NO 2 , respectively. When m=2 compound (IX) may be allowed to react with compound ##STR14## in the presence of a base catalyst to give compound (VIII), (V) or (VI) by Michael addition. When m=3 these compounds may be obtained by reaction of compound (IX) with an ester of formula Hal-(CH 2 ) 3 --CO 2 R 7 , where Hal is chloro, bromo or iodo, in the presence of a base such as sodium hydride in dimethylformamide as a solvent.
When R 10 is the acrylic ester group ##STR15## compound (IX) may be obtained from a bromoindole of formula (X): ##STR16## where R 1 , R 2 and X are as defined above by a Heck reaction with an appropriate acrylic ester in the presence of palladium (II) acetate, tri-o-tolylphosphine and a base such as triethylamine in a suitable solvent such as acetonitrile or dimethylformamide at a temperature from 80° to 160° C.
When R 10 is CN compound (IX) may be prepared from compound (X) by reaction of the latter with a cyanide, such as CuCN in a solvent such as dimethylformamide, dimethylacetamide or N-methylpyrrolidone at reflux temperature.
When indole intermediates in which X is CH 2 , R 2 is C 1 -C 4 alkyl and R 1 is not 1-imidazolyl are to be obtained, compounds (IX or X) in which X is a direct link and R 1 is H, R 2 is C 1 -C 4 alkyl may be obtained by the above-described methods and subsequently allowed to react with an appropriate aldehyde in the presence of trifluoroacetic acid and triethylsilane: ##STR17##
When X is CH 2 and R 1 is a 1-imidazolyl group in the desired compound the following synthesis may be used: ##STR18##
In this synthesis the starting compound in which R 2 is as defined above and R 10 is ##STR19## or CN reacts with formaldehyde, dimethylamine and acetic acid to give the corresponding indole having a --CH 2 NMe 2 substituent at the 3-position. Subsequent treatment with imidazole in a solvent such as toluene or xylene, at the boiling point of the solvent, results in replacement of the --NMe 2 group with a 1-imidazolyl group.
The bromo-indole intermediates of formula (X) may be prepared from known compounds by standard methods, such as the Fischer indole synthesis or by substitution of bromocompounds (X) in which X is a direct link and R 1 is H. For example, a compound of formula (XI): ##STR20## where R 2 is as defined above may be converted to a compound (X) where X is CH 2 by reaction with aldehyde R 1 CHO in the presence of trifluoroacetic acid and Et 3 SiH, or with a Grignard reagent MeMgHal where Hal is a halogen atom followed by reaction with halide R 1 CH 2 Cl or R 1 CH 2 Br.
The nitroindole intermediates (IX) in which R 10 is NO 2 may be made by known methods, such as the Fischer indole synthesis applied to the appropriate nitrophenylhydrazone. When X is CH 2 and R 1 is imidazolyl these intermediates may be prepared from those in which X is a direct link and R 1 is H by reaction with formaldehyde/dimethylamine/acetic acid followed by reaction with imidazole, as described above.
As previously mentioned, the compounds of the invention are able to antagonise the action of thromboxane A 2 and prostaglandin H 2 at the thromboxane A 2 receptor.
Thromboxane A 2 (TXA 2 ) is a naturally occurring prostanoid which is known to be a potent vascoconstrictor and platelet aggregating agent. TXA 2 is also believed to be involved in a number of disease states including atherosclerosis, ischaemic heart disease, peripheral vascular disease and myocardial infarction. TXA 2 acts at the thromboxane A 2 receptor, at which site other prostanoids, notably prostaglandin H 2 , may also be agonists.
TXA 2 synthetase inhibitors prevent formation of TXA 2 from the precursor PGH 2 which may be diverted to produce more of the vasodilator and antiaggregatory PGI 2 . However, a possible drawback with this type of agent is that accumulated PGH 2 substrate can activate the TXA 2 receptor, thus partly eliminating or negating the benefit of suppressing TXA 2 formation. Furthermore, if inhibition of TXA 2 synthetase is incomplete, sufficient TXA 2 may be available to induce some platelet activation. Both of these drawbacks can be overcome if a TXA 2 receptor antagonist is present to block the action of any TXA 2 or accumulated PGH 2 substrate. It has been demonstrated that combination of a TXA 2 antagonist and a TXA 2 synthetase inhibitor produces a synergistic effect on platelet aggregation in vitro (Watts et al., Brit. J. Pharmacol., 102, 497, 1991). In addition, administration of the TXA 2 antagonist sulotroban and the TXA 2 synthetase inhibitor dazoxiben to human volunteers gave a stronger inhibition of platelet aggregation than either agent alone (Gresele et al.,). Clin. Invest., 80, 1435, 1987).
Thus the compounds of the invention are of particular value when used in combination with a selective inhibitor of the thromboxane synthetase enzyme and the resulting combinations will find utility in the disease states already mentioned as well as those in which PGD 2 and PGF 2 α may be implicated as mediators, such as diabetes, bronchial asthma, and other inflammatory conditions.
Thus the present invention also provides a pharmaceutical composition comprising as active ingredients a novel TXA 2 receptor antagonist of the formula (I) as hereinbefore defined and a TXA 2 synthetase inhibitor, together with a pharmaceutically acceptable diluent or carrier.
Suitable TXA 2 synthetase inhibitors for inclusion as active ingredients in the composition according to the invention include, for example, the known compounds:
1) 4- 2-(1H-imidazol-1-yl)ethoxy!benzoic acid, (dazoxiben, R. P. Dickinson, et al, J. Med. Chem., 1985, 28, 1427-1432);
2) 3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoic acid, (dazmegrel, R. P. Dickinson, et al, J. Med. Chem., 1986, 29, 342-346);
3) 2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoic acid, (European patent 0054417);
4) 3-methyl-2-(3-pyridylmethyl)benzo b!thiophene-5-carboxylic acid, (UK-49,883, P. E. Cross, R. P. Dickinson, Spec Publ. Royal Soc. Chem. No. 50, p. 268-285, 1984);
5) 1,3-dimethyl-2-(1H-imidazol-1-ylmethyl)-1H-indol-5-carboxylic acid, (R. P. Dickinson et al, J. Med. Chem., 1986, 29, 1643-1650);
6) a carboxy, lower alkoxycarbonyl or carbamoyl substituted benzothiophene, benzofuran or indole as claimed in European patent 0073663, or the novel compound:
7) 2-methyl-3-(3-pyridyl)-1H-indole-1-pentanoic acid; or any other thromboxane synthetase inhibitor which acts in a synergistic manner and is chemically compatible with the novel compounds of formula (I).
Many of the compounds of the invention also inhibit the thromboxane synthetase enzyme in addition to their action as thromboxane receptor antagonists. Such compounds may therefore be effective in the absence of an additional thromboxane synthetase inhibitor. The biological activity of the compounds of the invention can be demonstrated using the following in vitro and in vivo assay procedures.
1. Thromboxane A 2 receptor antagonism
Spirally cut rat aortic strips, mounted for isometric tension recording in 20 ml organ baths, are bathed in Krebs-bicarbonate solution at 37° C. Following an incubation period of 2 hours under 1 gram resting tension, the tissues are pre-treated with U-46619 (a thromboxane A2 receptor agonist) for 10 minutes, then washed and the tissues allowed to equilibriate for a further 1 hour. Cumulative doses of U-46619 over the range 1 nM-100 nM are sequentially included in the bathing fluid and increases in the tissue tension noted.
The test compounds are incubated with the tissue for 15 minutes prior to repeating the cumulative dosing of U-46619 and the ability of the compound to antagonize the thromboxane A 2 receptor is determined from the dose-response curves for U-46619 in the presence of varied concentrations of the test compound.
2. Anaesthetised Rabbits
Thromboxane A 2 receptor antagonism is evaluated ex vivo in anaesthetised rabbits as follows:
New Zealand White rabbits (2-2.5 kg) are anaesthetised with fentanyl citrate (0.1 89 mg) and fluanisone (6 mg) intramuscularly and midazolam (3 mg) intravenously and maintained by an intravenous infusion of fentanyl citrate (0.315 mg), fluanisone (1 mg) and midazolam (1 mg) per hour. After cannulation of the trachea, a carotid artery is cannulated for collection of blood samples. The catheter is kept patent by the presence within the catheter of saline containing heparin (50 μ/ml). Control carotid arterial blood samples are taken 25 and 5 minutes prior to administration of the test compound via a marginal ear vein. Two groups of rabbits are used. The first group receives 0.01 mg/kg of the test compound followed, at ten minute intervals, by 0.03, 0.1, 0.3, 1.0, 3.0 and 10 mg/kg doses; the second group comprises the controls. Carotid arterial blood samples are taken 5 minutes after all doses. At each time point, a 900 μl blood sample is immediately mixed with 100 μl of trisodium citrate (3.15%). After 90 minutes incubation at room temperature, this sample is mixed in equal proportions with an aggregometry buffer (J. Pharmacol. Methods, 1981, 6, 315) and brought to 37° C. Electrodes for the measurement of electrical impedance are placed in the blood and U-46619 (final concentration 3 μM) is added to the blood. Antagonism of platelet thromboxane A 2 receptors by the compound is assessed by comparing the change in electrical impedance produced by U-46619 in compound-treated rabbits with the untreated controls.
3. Conscious Dogs
Thromboxane A 2 receptor antagonism may also be evaluated ex vivo in sling-restrained conscious dogs after oral (p.o.) or intravenous (i.v.) administration of a compound of the invention. The sampling and assaying procedures employed are similar to those described for the ex vivo anaesthetised rabbit experiments.
For administration to man, in the therapy or prevention of diseases or adverse medical conditions in which TXA 2 is implicated as a causative agent, oral dosages of the compounds would be expected to be in the range of from 20-800 mg daily for an average adult patient (70 kg). Thus for a typical adult patient, individual tablets or capsules contain from 10 to 400 mg of active compound, in a suitable pharmaceutically acceptable vehicle or carrier, for administration as a single dose, or in multiple doses, once or several times a day. Dosages for intravenous administration would typically be within the range of from 5 to 400 mg per single dose required. In practice the physician will determine the actual dosage which will be most suitable for an individual patient and it will vary with the age, weight and response of the particular patient, and with the condition being treated. The above dosages are exemplary of the average case but there can, of course, be individual instances where higher or lower dosage ranges are merited, and such are within the scope of this invention.
For human use, the compounds of the formula (I) can be administered alone, but will generally be administered in admixture with a pharmaceutical carrier selected with regard to the intended route of administration and standard pharmaceutical practice. For example, they may be administered orally in the form of tablets containing such excipients as starch or lactose, or in capsules or ovules either alone or in admixture with excipients, or in the form of elixirs or suspensions containing flavouring or colouring agents. They may be injected parenterally, for example, intravenously, intramuscularly or subcutaneously. For parenteral administration, they are best used in the form of a sterile aqueous solution which may contain other substances, for example enough salts or glucose, to make the solution isotonic with blood.
Thus the invention provides a pharmaceutical composition comprising a compound of formula (I), or a pharmaceutically acceptable salt or biolabile ester thereof, together with a pharmaceutically acceptable diluent or carrier.
The invention also provides a compound of formula (I), or a pharmaceutically acceptable salt or biolabile ester thereof, or a pharmaceutical composition containing any of these entities, for use in medicine.
The invention further includes the use of a compound of formula (I), or a pharmaceutically acceptable salt or a biolabile ester thereof, for the manufacture of a medicament for the treatment of disease conditions in which thromboxane A 2 is a causative agent.
In a further aspect, the invention provides a method of treating or preventing disease conditions in which thromboxane A 2 is a causative agent in a mammal (including a human being) which comprises administering to said mammal a therapeutically effective amount of a compound of formula (I), or a pharmaceutically acceptable salt, or a biolabile ester thereof.
The invention also includes any novel intermediates disclosed herein.
The synthesis of the compounds of the invention and of the intermediates for use in their preparation are illustrated by the following Examples and Preparations. The purity of the compounds was routinely monitored by thin layer chromatography (TLC) using Merck Kieselgel 60 F 254 plates and the following solvent systems (SS):
1. Dichloromethane;
2. Dichloromethane:methanol, 95:5;
3. Dichloromethane:methanol:0.880 ammonia, 90:10:1;
4. Toluene:diethylamine, 9:1;
5. Dichloromethane:methanol:0.880 ammonia, 100:20:1;
6. Dichloromethane:ethanol:ammonia, 98:2:0.2;
7. Dichloromethane:ethanol:ammonia, 90:10:1;
1 H-Nuclear magnetic reasonance (NMR) spectra were recorded using either a Nicolet QE-300 or a Bruker AC-300 spectrometer and were in all cases consistent with the proposed structures. Chemical shifts are given in parts-per-million downfield from tetramethylsilane using conventional abbreviations for designation of major peaks: s, singlet; d, doublet; t, triplet; m, multiplet and br, broad.
EXAMPLE 1
Methyl 5- 2- (4-fluorophenyl)sulphonyl!amino!ethyl!-3-(3-pyridylmethyl)-1H-indole-1 -propanoate
4-Fluorobenzenesulphonyl chloride (0.346 g) was added portionwise to a stirred solution of methyl 5-(2-aminoethyl)-3-(3-pyridylmethyl)-1H-indole1-propanoate (0.50 g) and triethylamine (0.33 g) in dichloromethane (5 ml) at room temperature. The mixture was stirred for 30 minutes and then washed with water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel using dichloromethane/methanol (50:1) as eluant. The product fractions were combined and evaporated to give the title compound as a gum (0.59 g).
Found: C,62.89; H,5.22; N,8.15. C 26 H 26 FN 3 O 4 S requires: C,63.01; H,5.29; N,8.48%.
EXAMPLES 2 to 27
The compounds of the following formula were prepared as in Example 1 using the appropriate sulphonyl chloride, sulphamoyl chloride or acyl chloride and the appropriate indole compound.
__________________________________________________________________________ ##STR21## R.sup.3 NH (CH.sub.2).sub.n Solvent, m.p.Ex R.sup.1 R.sup.2 position R.sup.3 R.sup.7 n m x Base °C. Analytical Data__________________________________________________________________________2 1-imidazolyl H 5 4-fluoro- Me 0 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 57.93; H, 4.66; phenyl Et.sub.3 N N, 12.13; sulphonyl C.sub.22 H.sub.21 FN.sub.4 O.sub.4 S requires: C, 57.88; H, 4.64; N, 12.27%.3 1-imidazolyl Me 5 4-fluoro- Me 0 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 58.45; H, 4.94; phenyl Pyridine N, 11.56; sulphonyl C.sub.23 H.sub.23 FN.sub.4 O.sub.4 S requires: C, 58.71; H, 4.93; N, 11.91%.4 4-fluorophenyl H 5 4-fluoro- Me 0 2 CH.sub.2 CH.sub.2 Cl.sub.2, 115- Found: C, 61.55; H, 4.24; phenyl Et.sub.3 N 118 N, 5.90. sulphonyl C.sub.29 H.sub.22 F.sub.2 N.sub.2 O.sub.4 S requires: C, 61.97; H, 4.58; N, 5.78%.5 4-fluorophenyl H 5 4-chloro- Me 0 2 CH.sub.2 CH.sub.2 Cl.sub.2, 120- Found: C, 60.14; H, 4.35; phenyl Et.sub.3 N 123 N, 5.56; sulphonyl C.sub.25 H.sub.22 ClFN.sub.2 O.sub.4 S requires: C, 59.94; H, 4.43; N, 5.59%.6 3-pyridyl H 5 4-chloro- Me 0 2 direct CH.sub.2 Cl.sub.2, 176- Found: C, 58.96; H, 4.13; phenyl link Et.sub.3 N 178 N, 8.79; sulphonyl C.sub.23 H.sub.20 ClN.sub.2 O.sub.4 S requires: C, 58.78; H, 4.29; N, 8.94%.7 3-pyridyl H 5 4-chloro- Et 0 3 direct CH.sub.2 Cl.sub.2, 209- Found: C, 60.11; H, 4.83; phenyl link Et.sub.3 N 211 N, 8.33; sulphonyl C.sub.25 H.sub.24 ClN.sub.2 O.sub.4 S requires: C, 60.29; H, 4.86; N, 8.44%.8 3-pyridyl H 5 4-fluoro- Me 0 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 61.66; H, 4.63; phenyl Et.sub.3 N N, 8.95; sulphonyl C.sub.24 H.sub.22 FN.sub.2 O.sub.4 S requires: C, 61.65; H, 4.74; N, 8.99%.9 3-pyridyl H 5 4-fluoro- Me 0 3 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 63.01; H, 5.35; phenyl Et.sub.3 N N, 8.32; sulphonyl C.sub.26 H.sub.26 FN.sub.2 O.sub.4 S requires: C, 63.01; H, 5.29; N, 8.48%.10 1-imidazolyl Me 5 4-fluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Rf. 0.55(SS3) phenyl Pyridine δ(CDCl.sub.3): 2.47(3H, s), 2.74- sulphonyl 2.87(4H, m), 3.24(2H, m), 3.69(3H, s), 4.43(2H, t), 4.62(1H, t), 5.20(2H, s), 6.86(1H, s), 6.92(1H, dd), 7.02(1H, s), 7.05-7.15 (3H, m), 7.23(1H, d), 7.49(1H, s), 7.77(2H, m).11 1-imidazolyl Me 4 4-fluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 59.98; H, 5.53; phenyl DMAP N, 10.94; sulphonyl C.sub.26 H.sub.27 FN.sub.4 O.sub.4 S requires: C, 60.22; H, 5.46; N, 11.24%.12 3-pyridyl H 5 methyl- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Found: C, 59.37; H, 5.89; sulphonyl Et.sub.3 N N, 9.71; C.sub.21 H.sub.25 N.sub.3 O.sub.4 S. O.1CH.sub.2 Cl.sub.2 requires: C, 59.77; H, 5.99; N, 9.91%.13 3-pyridyl H 5 dimethyl- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Rf. 0.6(SS3) amino- DMAP/ δ(CDCl.sub.3): 2.75(6H, s), sulphonyl Et.sub.3 N 2.82(2H, t), 2.94(2H, t), (1.5:1) 3.34(2H, m), 3.67(3H, s), 4.08(2H, s), 4.14(1H, t), 4.42(2H, t), 6.87(1H, s), 7.08(1H, d), 7.20- 7.24(1H, m), 7.29-7.32 (2H, m), 7.55(1H, d), 8.46(1H, d), 8.60(1H, s).14 3-pyridyl H 5 3-methyl- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Found: C, 68.52; H, 7.09; butanoyl Et.sub.3 N N, 9.59; C.sub.25 H.sub.31 N.sub.3 O.sub.3. 0.25CH.sub.2 Cl.sub.2 requires: C, 68.49; H, 7.17; N, 9.49%.15 3-pyridyl H 4 4-fluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Rf. 0.6(SS3) sulphonyl Et.sub.3 N δ(CDCl.sub.3): 2.78(2H, t), 3.00(2H, t), 3.13(2H, m), 3.65(3H, s), 4.13(2H, s), 4.35-4.44(3H, m), 6.72 (1H, s), 6.74(1H, d), 7.07- 7.24(5H, m), 7.41(1H, d), 7.74(1H, m), 8.44(2H, m).16 3-pyridyl H 4 dimethyl- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Rf. 0.5(SS3) amino Et.sub.3 N δ(CDCl.sub.3): 2.70(6H, s), sulphonyl 2.79(2H, m), 3.08(2H, t), 3.26(2H, m), 3.66(3H, s), 4.10(1H, t), 4.23(2H, s), 4.38(2H, t), 6.74(1H, s), 6.88(1H, d), 7.13-7.23 (3H, m), 7.46(1H, d), 8.46- 8.49(2H, m).17 3-pyridyl H 4 3-methyl Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, 113- Found: C, 71.61; H, 7.11; butanoyl Et.sub.3 N/ 115 N, 9.96; DMAP(1:1) C.sub.25 H.sub.31 N.sub.3 O.sub.3 requires: C, 71.23; H, 7.41; N, 9.97%.18 3-pyridyl Me 5 4-fluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Rf. 0.55(SS2) phenyl Et.sub.3 N δ(CDCl.sub.3): 2.39(3H, s), sulphonyl 2.71-2.80(4H, m), 3.17- 3.24(2H, m), 3.67(3H, s), 4.01(2H, s), 4.34-4.43 (3H, m), 6.85(1H, d), 7.02 (1H, s), 7.05-7.15(3H, m), 7.20(1H, d), 7.39(1H, d), 7.70-7.75(2H, m), 8.40(1H, d), 8.49(1H, s).19 3-pyridyl Me 5 4-iodo- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 52.89; H, 4.55; phenyl- Et.sub.3 N N, 6.75; sulphonyl C.sub.27 H.sub.28 IN.sub.2 O.sub.4 S requires: C, 52.51; H, 4.57; N, 6.81%.20 3-pyridyl Me 5 4-trifluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Foam Found: C, 59.99; H, 5.09; methyl Et.sub.3 N N, 7.34; phenyl C.sub.28 H.sub.28 F.sub.3 N.sub.2 O.sub.4 S requires: sulphonyl C, 60.09; H, 5.04; N, 7.51%.21 3-pyridyl Me 4 4-fluoro- Me 2 2 CH.sub.2 CH.sub.2 Cl.sub.2, Gum Rf. 0.7(SS3) phenyl Et.sub.3 N δ(CDCl.sub.3): 2.35(3H, s), sulphonyl 2.76(2H, t), 2.89(2H, t), 3.05(2H, m), 3.68(3H, s), 4.14(2H, s), 4.39-4.48 (3H, m), 6.70(1H, d), 7.05- 7.12(4H, m), 7.20- 7.26(2H, m), 7.68- 7.72(2H, m), 8.33-8.38 (2H, m).22 H H 5 4-chloro- Me O 2 direct CH.sub.2 Cl.sub.2, Gum Found: C, 55.21; H, 4.36; phenyl link Et.sub.3 N N, 6.74; sulphonyl C.sub.18 H.sub.17 ClN.sub.2 O.sub.4 S requires: C, 55.04; H, 4.36; N, 7.13%.23 H H 5 4-fluoro- Me O 2 direct CH.sub.2 Cl.sub.2, Gum Found: C, 57.41; H, 4.61; phenyl link Et.sub.3 N N, 7.32; sulphonyl C.sub.18 H.sub.17 FN.sub.2 O.sub.4 S requires: C, 57.44; H, 4.55; N, 7.44%.24 4-fluoro- H 5 Phenyl- Me O 2 CH.sub.2 CH.sub.2 Cl.sub.2, 109- Found: C, 64.65; H, 5.05; phenyl sulphonyl Et.sub.3 N 112 N, 5.91; C.sub.25 H.sub.23 FN.sub.2 O.sub.4 S requires: C, 64.36; H, 4.97; N, 6.00%.25 4-fluoro- H 5 4-trifluoro- Me O 2 CH.sub.2 CH.sub.2 Cl.sub.2, 100- Found: C, 58.30; H, 4.09; phenyl methyl- Et.sub.3 N 103 N, 5.38; phenyl- C.sub.26 H.sub.22 F.sub.4 N.sub.2 O.sub.4 S requires: sulphonyl C, 58.42; H, 4.15; N, 5.24%.26 4-fluoro- H 5 4-methoxy- Me O 2 CH.sub.2 CH.sub.2 Cl.sub.2, 161- Found: C, 62.91; H, 5.00; phenyl phenyl- Et.sub.3 N 162 N, 5.43; sulphonyl C.sub.26 H.sub.25 FN.sub.2 O.sub.5 S requires: C, 62.89; H, 5.07; N, 5.64%.27 4-fluoro- H 5 4-methyl- Me O 2 CH.sub.2 CH.sub.2 Cl.sub.2, 145- Found: C, 65.06; H, 5.32; phenyl phenyl- Et.sub.3 N 148 N, 5.85; sulphonyl C.sub.26 H.sub.25 FN.sub.2 O.sub.4 S requires: C, 64.98; H, 5.24; N,__________________________________________________________________________ 5.83%.
EXAMPLE 28
Methyl 5- (2-cyclopropyl)acetyl!amino!ethyl-3-(3-pyridylmethyl))-1H-indole-1-propanoate
A mixture of cyclopropylacetic acid (0.25 g) and carbonyldiimidazole (0.288g) in dry tetrahydrofuran (9 ml) was heated under reflux until evolution ofCO 2 ceased. A solution of methyl 5-(2-aminoethyl)-3-(3-pyridylmethyl)-1H-indole-1-propanoate (0.50 g) in dry dichloromethane (5 ml) was added and the solution was stirred at room temperature for 56 hours and then evaporated. The residue was partitioned between ethyl acetate and water. The organic layer was washed twice with water, dried (MgSO 4 ) and evaporated. The residue was chromatographed on silica gel. Elution with dichloromethane gave starting material, and then further elution with dichloromethane/methanol (19:1) gave pure product. The product fractions were evaporated to give the title compound as a gum (0.497 g). Rf. 0.7 (SS3).
δ(CDCl 3 ): 0.10(2H,m), 0.48(2H,m), 0.85(1H,m), 2.10(2H,d), 2.82(2H,t) 2.91(2H,t), 3.57(2H,m), 3.67(3H,s), 4.07(2H,s), 4.42(2H,t), 5.90(1H,br), 6.85(1H,s), 7.08(1H,d), 7.22(1H,m), 7.29-7.32(2H,m), 7.57(1H,d), 8.48(1H,d), 8.57(1H,s).
EXAMPLE 29
5- (4-Fluorophenyl)sulphonyl!amino-3-(3-pyridylmethyl)-1H-indole-1-propanoic acid
A mixture of methyl 5- (4-fluorophenyl)sulphonyl!-amino-3-(3-pyridylmethyl)-1H-indole-1-propanoate (the product of Example 8) ((1.10 g), sodium hydroxide (0.47 g), methanol (2 ml) and water (10 ml) was heated under reflux for 75 minutes and then evaporated to a small volume. The solution was acidified with acetic acid to give a gum which solidified on scratching. The solid was filtered off, washed with water and dried. Crystallisation from ethyl acetate/methanol gave the title compound (0.64 g), m.p. 214°-215° C. Found: C,61.18; H,4.23; N,9.28. C 23 H 20 FN 3 O 4 S requires: C,60.91; H,4.44; N,9.26%.
EXAMPLES 30-56
The procedure of Example 29 was repeated but using the appropriate startingmaterial to produce compounds of the following formula given in the following Table:
__________________________________________________________________________ ##STR22## R.sup.3 NH(CH.sub.2).sub.n m.p.Ex R.sup.1 R.sup.2 position R.sup.3 n m x °C. Analytical Data__________________________________________________________________________30 1-imidazolyl H 5 4-fluorophenyl 0 2 CH.sub.2 208- Found: C, 57.47; H, 4.15; N, 12.60; sulphonyl 210 C.sub.21 H.sub.19 FN.sub.4 O.sub.4 S requires: C, 57.00; H, 4.33; N, 12.66%.31 1-imidazolyl Me 5 4-fluorophenyl 0 2 CH.sub.2 Foam Rf. 0.1(SS3) sulphonyl δ(CDCl.sub.3): 2.44(3H, s), 2.60(2H, t), 4.27(2H, t), 5.19(2H, s), 6.77(1H, d), 6.82(1H, s), 6.89(1H, s), 7.18(1H, s), 7.29-7.33(3H, m), 7.58(1H, s), 7.66- 7.70(2H, m), 9.97(1H, s).32 4-fluorophenyl H 5 4-fluorophenyl 0 2 CH.sub.2 185- Found: C, 60.78; H, 4.19; N, 5.74; sulphonyl 188 C.sub.24 H.sub.20 F.sub.2 N.sub.2 O.sub.4 S requires: C, 61.27; H, 4.28; N, 5.75%.33 4-fluorophenyl H 5 4-chlorophenyl 0 2 CH.sub.2 144- Found: C, 59.33; H, 3.93; N, 5.55; sulphonyl 147 C.sub.24 H.sub.20 ClFN.sub.2 O.sub.4 S requires: C, 59.20; H, 4.14; N, 5.75%.34 3-pyridyl H 5 4-chlorophenyl 0 2 direct 235- Found: C, 58.28; H, 3.71; N, 9.04; sulphonyl link 237 C.sub.22 H.sub.18 ClN.sub.3 O.sub.4 S requires: C, 57.95; H, 3.98; N, 9.22%.35 3-pyridyl H 5 4-chlorophenyl 0 3 direct 199- Found: C, 58.63; H, 4.16; N, 8.81; sulphonyl link 201 C.sub.23 H.sub.20 ClN.sub.3 O.sub.4 S requires: C, 58.78; H, 4.29; N, 8.94%.36 3-pyridyl H 5 4-fluorophenyl 0 3 CH.sub.2 154- Found: C, 61.80; H, 4.68; N, 8.91; sulphonyl 156 C.sub.24 H.sub.22 FN.sub.3 O.sub.4 S requires: C, 61.65; H, 4.74; N, 8.99%.37 1-imidazolyl Me 5 4-fluorophenyl 2 2 CH.sub.2 165- Found: C, 58.99; H, 5.40; N, 10.96; sulphonyl 167 C.sub.24 H.sub.25 FN.sub.4 O.sub.4 S requires: C, 59.49; H, 5.70; N, 11.57%.38 1-imidazolyl Me 4 4-fluorophenyl- 2 2 CH.sub.2 Foam Rf. 0.15(SS3). sulphonyl δ(DMSOd.sub.6): 2.45(3H, s), 2.63(2H, t), 2.79(2H, t), 2.85(2H, m), 4.37(2H, t), 5.24(2H, s), 6.72(1H, d), 6.82(1H, s), 6.88(1H, s), 6.98(1H, dd), 7.30-7.40 (3H, m), 7.45(1H, s), 7.79(2H, m), 8.91 (1H, t).39 3-pyridyl H 5 4-fluorophenyl- 2 2 CH.sub.2 158-160 Found: C, 61.98; H, 5.26; N, 8.52; sulphonyl C.sub.25 H.sub.24 FN.sub.3 O.sub.4 S requires: C, 62.35; H, 5.02; N, 8.73%.40 3-pyridyl H 5 methylsulphonyl 2 2 CH.sub.2 180- Found: C, 60.07; H, 5.78; N, 10.25; 182.5 C.sub.20 H.sub.23 N.sub.3 O.sub.4 S requires: C, 59.83; H, 5.77; N, 10.47%.41 3-pyridyl H 5 dimethylamino- 2 2 CH.sub.2 160-161 Found: C, 58.88; H, 5.81; N, 12.93; sulphonyl C.sub.21 H.sub.25 N.sub.4 O.sub.4 S requires: C, 58.58; H, 6.09; N, 13.02%.42 3-pyridyl H 5 3-methyl- 2 2 CH.sub.2 171- Found: C, 71.03; H, 6.79; N, 10.27; butanoyl 172.5 C.sub.24 H.sub.20 N.sub.3 O.sub.3 requires: C, 70.73; H, 7.17; N, 10.31%.43 3-pyridyl H 5 cyclopropyl- 2 2 CH.sub.2 159- Found: C, 71.17; H, 6.72; N, 9.89; acetyl 161 C.sub.24 H.sub.27 N.sub.3 O.sub.3 requires: C, 71.08; H, 6.71; N, 10.36%.44 3-pyridyl H 4 4-fluorophenyl 2 2 CH.sub.2 93-95 Found: C, 62.20; H, 5.00; N, 8.76; sulphonyl C.sub.25 H.sub.24 FN.sub.3 O.sub.4 S requires: C, 62.35; H, 5.02; N, 8.73%.45 3-pyridyl H 4 dimethylamino 2 2 CH.sub.2 179- Found: C, 58.96; H, 6.00; N, 12.56; sulphonyl 181 C.sub.21 H.sub.26 N.sub.4 O.sub.4 S requires: C, 58.58; H, 6.09; N, 13.02%.46 3-pyridyl H 4 3-methyl- 2 2 CH.sub.2 195- Found: C, 70.97; H, 7.11; N, 10.26; butanoyl 196 C.sub.24 H.sub.29 N.sub.3 O.sub.3 requires: C, 70.73; H, 7.17; N, 10.31%.47 3-pyridyl Me 5 4-fluorophenyl 2 2 CH.sub.2 197- Found: C, 62.49; H, 5.07; N, 8.15; sulphonyl 199 C.sub.26 H.sub.26 FN.sub.3 O.sub.4 S requires: C, 63.01; H, 5.29; N, 8.48%.48 3-pyridyl Me 5 4-iodophenyl 2 2 CH.sub.2 173- Found: C, 52.02; H, 4.27; N, 6.81; sulphonyl 176 C.sub.26 H.sub.26 IN.sub.3 O.sub.4 S requires: C, 51.74; H, 4.34; N, 6.96%.49 3-pyridyl Me 5 4-trifluoro- 2 2 CH.sub.2 185- Found: C, 59.51; H, 4.84; N, 7.53; methylphenyl- 187 C.sub.27 H.sub.26 F.sub.3 NO.sub.4 S requires: C, 59.44; sulphonyl H, 4.80; N, 7.70%.50 3-pyridyl Me 4 4-fluorophenyl 2 2 CH.sub.2 218- Found: C, 63.07; H, 5.19; N, 8.38; sulphonyl 220 C.sub.26 H.sub.26 FN.sub.3 O.sub.4 S requires: C, 63.01; H, 5.29; N, 8.38%.51 H H 5 4-chlorophenyl 0 2 direct 174- Found: C, 54.29; H, 4.12; N, 7.16; sulphonyl link 176 C.sub.17 H.sub.15 ClN.sub.2 O.sub.4 S requires: C, 53.90; H, 3.99; N, 7.39%.52 H H 5 4-fluorophenyl 0 2 direct 140- Found: C, 55.91; H, 4.08; N, 7.30; sulphonyl link 141 C.sub.17 H.sub.15 FN.sub.2 O.sub.4 S requires: C, 56.33; H, 4.17; N, 7.73%.53 4-fluoro- H 5 phenyl- O 2 CH.sub.2 178- Found: C, 63.37; H, 4.59; N, 5.90; phenyl sulphonyl 181 C.sub.24 H.sub.21 FN.sub.2 O.sub.4 S requires: C, 63.70; H, 4.68; N, 6.19%.54 4-fluoro- H 5 4-trifluoro- O 2 CH.sub.2 171- Found: C, 58.14; H, 3.61; N, 5.01; phenyl methylphenyl- 175 C.sub.25 H.sub.20 F.sub.4 N.sub.2 O.sub.4 S requires: C, 57.69; sulphonyl H, 3.87; N, 5.38%.55 4-fluoro- H 5 4-methoxy- O 2 CH.sub.2 166- Found: C, 62.14; H, 4.73; N, 5.93; phenyl phenyl- 168 C.sub.25 H.sub.23 FN.sub.2 O.sub.5 S requires: C, 62.23; sulphonyl H, 4.80; N, 5.81%.56 4-fluoro- H 5 4-methyl- O 2 CH.sub.2 203- Found: C, 64.12; H, 4.79; N, 5.95; phenyl phenyl- 206 C.sub.25 H.sub.23 FN.sub.2 O.sub.4 S requires: C, 64.36; sulphonyl H, 4.97; N, 6.00%.__________________________________________________________________________
EXAMPLE 57
1,2-Dimethyl-5- (4-fluorophenyl)sulphonyl!amino-1H-indole-1-propanoic acid
A solution of 5- (4-fluorophenyl)sulphonyl!amino-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoic acid (0.30 g) in ethanol (5 ml) and acetic acid (5 ml) was hydrogenated for 24 hours at 50° C. and 4.5 atm. in the presence of 10% palladium on carbon (30 mg). The mixture was filtered and the residue was washed with ethanol. The filtrate and washings were combined and evaporated, and the residue was partitioned between ethyl acetate and water. The organic layer was washed twice with water and dried(MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel, using dichloromethane/methanol (19:1) as eluant. The product fractions were combined and evaporated to give the title compound as a gum (0.035 g), Rf. 0.75(SS7). δ(DMSOd 6 ): 1.96(3H,s), 2.25(3H,s), ca 2.48(2H,t), 4.20(2H,t), 6.70(1H,d), 6.98(1H,s),7.15(1H,d), 7.26(2H,m), 7.66(2H,m), 9.71 (1H,s).
EXAMPLE 58
______________________________________Pharmaceutical Capsules mg/capsule______________________________________Thromboxane A.sub.2 Antagonist 50.0Thromboxane Synthetase Inhibitor 150.0Starch 49.0Magnesium stereate BP 1.0 250 mg______________________________________
The thromboxane A 2 antagonist and the thromboxane synethase inhibitor are sieved and blended with the starch and the excipients. The mix is filled into size No. 2 hard gelatin capsules, using suitable machinery. Capsules of other strengths or with different ratios of active ingredientsmay be prepared in a similar manner.
Regarding toxicity, the compounds of Examples 33,41,42,46 and 49 have each been administered acutely to dogs at doses up to 10 mg/kg orally. No signsof toxicity were observed.
PREPARATION 1
3-(1H-Imidazol-1-ylmethyl)-5-nitro-1H-indole
A mixture of N,N-dimethyl-5-nitro-1H-indole-3-methanamine (J.Med, Chem, 9, 140,(1966)) (9.10 g) and imidazole (2.96 g) in xylene (120 ml) was heated under reflux for 2.5 hours and then cooled. The solid was filtered off, washed with ether and dried to give the title compound (9.40 g), m.p. 230°-232° C. (from ethyl acetate/methanol). Found: C,59.85; H,4.39; N,22.80. C 12 H 10 N 4 O 2 requires: C,59.50; H,4.16; N,23.13%.
PREPARATION 2
3-(1H-Imidazol-1-ylmethyl)-2-methyl-5-nitro-1H-indole
Treatment of 2, N,N-trimethyl-5-nitro-1H-indole-3-methanamine (J.Org.Chem.,28,2921(1963)) (5.60 g) with imidazole (1.90 g) in xylene (100 ml) according to the method of Preparation 1 gave the title compound (5.50 g),m.p. 240°-242° C. Found: C,61.02; H,4.41; N,21.68. C 13 H 12 N 4 O 2 requires: C,60.92; H,4.72; N,21.87%.
PREPARATION 3
5-Nitro-3-(3-pyridylmethyl)-1H-indole
a) 3-(3-Pyridyl)propanal
Dimethylsulphoxide (18.9 ml) in dry dichloromethane (120 ml) was added over20 minutes to a stirred solution of oxalyl chloride (11.55 ml) in dry dichloromethane (225 ml) at -70° C. The mixture was stirred at -70° C. for 10 minutes and then a solution of 3-(3-pyridyl)propanol(16.56 g) in dry dichloromethane (120 ml) was added with stirring over 20 minutes. Stirring was continued at -70° C. for a further 20 minutesand then triethylamine (50.55 ml) was added dropwise and the temperature was allowed to rise to room temperature. Water (200 ml) was added and the layers were separated. The organic layer was washed twice with water, dried (MgSO 4 ) and evaporated. The residue was distilled to give the title compound as an oil (8.80 g), b.p. 88°-92° C. @ 0.3 mm., Rf. 0.15 (SS2). δ(CDCl 3 ): 2.80(3H,t), 2.93(3H,t), 7.18-7.21 (1H,m), 7.50(1H,d), 8.40-8.45(2H,m), 9.80(1H,s).
b) 3-(3-Pyridyl)propanal-4-nitrophenylhydrazone
3-(3-Pyridyl)propanal (8.50 g) was added to a stirred suspension of 4-nitrophenylhydrazine (9.62 g) in ether 150 ml. After a minute an orange-brown oil formed which solidified on further stirring. The solid was filtered off to give the title compound pure enough for further reaction (14.05 g), m.p. 146°-147° C. (from ethyl acetate/methanol). Found: C,62.12; H,5.02; N,20.36. C 14 H 14 N 4 O 2 requires: C,62.21; H,5.22; N,20.73%.
c) 5-Nitro-3-(3-pyridylmethyl)-1H-indole
The above hydrazone (15 g) was added portionwise to a stirred mixture of polyphosphoric acid (60 g) and toluene (180 ml). The mixture was then heated at 110° C. with stirring for 1 hour and then cooled, poured into water and basified with concentrated aqueous ammonia solution. The aqueous layer was separated and extracted three times with ethyl acetate. The organic layers were combined, washed with water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel. Elution with dichloromethane/methanol (40:1), gradually increasing the polarity to 25:1, gave the title compound(9.4 g), m.p. 154°-156° C. (from ethyl acetate). Found: C,66.68; H,4.19; N,16.61. C 14 H 11 N 3 O 2 requires: C,66.39; H,4.38; N,16.59%.
PREPARATION 4
5-Nitro-3-(3-pyridyl)-1H-indole
a) 3-(2-EZ-methoxyethenyl)pyridine
Phenyllithium (111 ml of 1.8M solution in ether) was added dropwise to a stirred suspension of (methoxymethyl) triphenylphosphonium chloride (68.6 g) in dry ether (600 ml) at -50° C. The mixture was stirred at -50° C. for 2 hours and then allowed to reach 0° C. over 30 minutes. 3-Pyridinecarboxaldehyde (10.70 g) was added dropwise with stirring, and the mixture was stirred at room temperature for 18 hours. Anexcess of ammonium chloride solution was then added and the layers were separated. The aqueous layer was separated and washed with ether, and the organic layers were combined and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel initially using ethyl acetate/hexane (1:4) as eluant. The polarity was gradually increased to ethyl acetate/hexane (1:1) to give the pure product as an oil(8.82 g) which was used directly in the next stage.
b) 3-Pyridineacetaldehyde-4-nitrophenylhydrazone
A solution of 3-(2-EZ-methoxyethenyl)pyridine (3.43 g) in ethanol (15 ml) and 2N hydrochloric acid (25 ml) was heated under reflux for 1 hour and then cooled. 4-nitrophenylhydrazine (3.89 g) was added portionwise with stirring to give a solution which deposited a yellow solid. The mixture was cooled in ice and the solid was filtered off, washed with isopropanol,ether and then dried to give the title compound (5.32 g), m.p. 212°-214° C. Found: C,53.54; H,4.51; N,19.00. C 13 H 12 N 4 O 2 requires: C,53.34; H,4.48; N,19.14%.
5-Nitro-3-pyridyl-1H-indole
The above hydrazone (4.30 g) was added to ice-cooled concentrated sulphuricacid (43 ml) at such a rate that the temperature did not rise above 20° C. The mixture was stirred at room temperature for 1 hour and was then stirred at 30° C. for a further 1 hour. It was carefully poured into 500 ml of ice water and the solution was basified with concentrated aqueous ammonia solution with cooling. The mixture was extracted twice with ethyl acetate and the combined extracts were washed with water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel. Elution with ethyl acetate followed by ethyl acetate/methanol (19:1) gave the title compound (1.25 g), m.p. >265° C. Found: C,65.34; H,3.41; N,17.69. C 13 H 19 N 3 O 2 requires: C,65.26; H,3.79; N,17.57%.
PREPARATION 5
3-(4-Fluorophenylmethyl)-5-nitro-1H-indole
a) 3-(4-Fluorophenyl)propanal
Di-isobutylaluminium hydride (75 ml of 1.0M solution in toluene) was added dropwise to a stirred solution of ethyl (4-fluorophenyl)-propanoate (J.Org.Chem.,31, 1524 (1966)) (11.84 g) in toluene (130 ml) at -70°C. The solution was stirred at -70° C. for 90 minutes, then ca 100 ml of 15% ammonium chloride solution was added dropwise and the temperature was allowed to reach room temperature. The organic layer was separated, dried (Na 2 SO 4 ) and evaporated to give an oil which was chromatographed on silica gel. Elution with dichloromethane/hexane (3:1) gave the title compound as an oil (7.05 g), Rf. 0.7(SS1).
δ(CDCl 3 ): 2.77(2H,t), 2.93(2H,t), 6.94-7.00(2H,m), 7.13-7.17(2H,m) 9.81(1H,s).
b) 3-(4-Fluorophenyl)propanal-4-nitrophenylhydrazone
A solution of 3-(4-fluorophenyl)propanal (7.0 g) in ether (50 ml) was addedto a stirred suspension of 4-nitrophenylhydrazine (7.0 g) in ether (1 50 ml), followed by sufficient ethyl acetate to achieve a clear solution. Thesolution was filtered and evaporated and the residue was crystallised from ethyl acetate/hexane to give the title compound (5.48 g), m.p. 125°-127° C. Found: C,62.81; H,4.87; N,14.44. C 15 H 14 FN 3 O 2 requires: C,62.71; H,4.91; N,14.63%.
Evaporation of the filtrate and trituration of the residue with hexane gavea further 5.39 g of title compound pure enough for further reaction.
c) 3-(4-Fluorophenylmethyl)-5-nitro-1H-indole
The above hydrazone (1 0.5 g) was added portionwise to a stirred mixture ofpolyphosphoric acid (45 g) and toluene (120 ml) at 40° C. The resulting mixture was stirred at 105°-110° C. for 75 minutesand then cooled. The toluene layer was decanted off and the residue was poured into water. The mixture was extracted twice with toluene and all the organic layers were combined, washed with water and dried (Na 2 SO 4 ). Evaporation of the solvent gave a solid which was crystallised from ethyl acetate to give the title compound (2.20 g), m.p. 142°-144° C. Found: C,66.44; H,3.68; N,10.00. C 15 H 11 FN 2 O 2 requires: C,66.66; H,4.10; N,10.37%.
PREPARATION 6
5-Bromo-3-(3-pyridylmethyl)-1H-indole
Methyl magnesium iodide (4.0 ml of 3M solution in ether) was added over 5 minutes to a stirred solution of 5-bromo-1H-in dole (1.96 g) in dry tetrahydrofuran (25 ml) at 2° C., the resulting suspension was stirred at room temperature for 45 minutes. Separately, a solution of 3-(chloromethyl)pyridine was prepared by partitioning 3-(chloromethyl)pyridine hydrochloride (1.97 g) between water and dichloromethane followed by dropwise addition of triethylamine with shaking until the pH of the aqueous layer was >7. The layers were separated and the aqueous layer was extracted with dichloromethane. The organic layers were combined, dried (MgSO 4 ) and evaporated to ca 25 ml. The solution was dried for a further 20 minutes by the addition of 3A molecular sieves. It was then added dropwise with stirring to the suspension of the indole Grignard reagent. The mixture was heated at 75° C. for 2 hours with stirring and then allowed to cool to room temperature. A solution of ammonium chloride (1.0 g) in water (30 ml) was added with stirring and the resulting mixture was extracted several times with ethyl acetate. The combined organic layers were washed with water, dried (MgSO 4 ) and evaporated. The residue was chromatographed on silica gel using dichloromethane/methanol (50:1) as eluent. Impurity was eluted first followed by pure product. The product fractions were combinedand evaporated and the residue was crystallised from ether to give the title compound (0.798 g), m.p. 126°-128° C. Found: C,58.76; H,3.92; N,9.67. C 14 H 11 BrN 2 requires: C,58.55; H,3.86; N,9.76%.
PREPARATION 7
4-Bromo-3-(3-pyridylmethyl)-1H-indole
Treatment of 4-bromo-1H-indole (J.Org.Chem., 48 2066(1983)) (16.95 g) with methyl magnesium bromide (34.6 ml of 3M solution in ether) followed by a dichloromethane solution of 3-(chloromethyl)pyridine (prepared from 17.02 g of 3-(chloromethyl)pyridine hydrochloride) according to the method of Preparation 6 gave the title compound (7.80 g), m.p. 173°-174° C. Found: C,58.90; H,3.88; N,9.80. C, 14 H 11 BrN 2 requires: C,58.55; H,3.86; N,9.76%.
PREPARATION 8
5-Bromo-2-methyl-3-(3-pyridylmethyl)-1H-indole
A solution of 5-bromo-2-methyl-1H-indole (J. Chem. Soc., 1428 (1965)) (2.0 g) and 3-pyridinecarboxaldehyde (1.02 g) in dry dichloromethane (20 ml) was added dropwise over 10 minutes to a stirred solution of triethylsilane(3.30 g) in trifluoroacetic acid (20 ml) at 0° C. The solution was stirred at 0° C. for 30 minutes and then evaporated under vacuum, keeping the temperature below 35° C. The residue was dissolved in dichloromethane, and the solution was washed with 2N sodium hydroxide, water and dried (MgSO 4 ). The solution was evaporated and the residue was chromatographed on silica gel, using dichloromethane/methanol (50:1) as eluent. The product fractions were combined and evaporated, and the residue was crystallised from ether to give the title compound (2.15 g), m.p. 188°-190° C. Found: C,59.62; H,4.43; N,9.26. C 15 H 13 BrN 2 requires: C,59.82; H,4.35; N,9.30%.
PREPARATION 9
4-Bromo-2-methyl-1H-indole and 6-bromo-2-methyl-1H-indole
3-Bromophenylhydrazine hydrochloride (26.5 g) was partitioned between etherand excess 2N sodium hydroxide solution. The ether layer was separated, washed with brine, dried (MgSO 4 ) and evaporated. The residue was redissolved in ether (25 ml) and the solution was cooled in ice. Acetone (25 ml) was added and the mixture was allowed to stand for 20 minutes and then evaporated. The residue was dissolved in acetone (25 ml), the solution was evaporated and the residue azeotroped with xylene. The residue was dissolved in xylene (30 ml) and the solution was added dropwise to stirred polyphosphoric acid (200 g) at 90° C. The mixture was stirred at 100° C. for 4 hours and then cooled and poured into ice water with stirring. The mixture was extracted twice with ether, and the combined extracts were washed with brine and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel using dichloromethane/hexane (1:4) as eluent. The product fractions were combined and evaporated, and the residue was crystallised twice from hexane to give 6-bromo-2-methyl-1H-indole (8.70 g), m.p. 132°-134° C. δ(CDCl 3 ): 2.38(3H,s), 6.15(1H,s), 7.12(1H,dd), 7.32(1H,d), 7.36(1H,d), 7.77(1H,br).
The hexane filtrates were combined and evaporated, and the residue was chromatographed as before to give an oil (8.35 g) shown by nmr to consist of a mixture of 4-bromo-2-methyl-1H-indole and 6-bromo-2-methyl-1H-indole in the ratio 3:1.
δ(CDCl 3 ) for the 4-bromo isomer: 2.45(3H,s), 6.29(1H,s), 6.95(1H,dd), 7.21-7.27(2H,m), 7.96(1H,br).
PREPARATION 10
Benzyl (E)-3-(2-methyl-1H-indol-4-yl)-2-propenoate
A mixture of 4-bromo-2-methyl-1H-indole (containing 25% of the 6-bromo isomer) (8.30 g), palladium (II) acetate (0.45 g), tri-o-tolylphosphine (1.22 g), benzyl acrylate (9.76 g) and triethylamine (8.36 ml) in acetonitrile (8 ml) was heated in an oil bath at 140° C. under an atmosphere of nitrogen for 2 hours. The mixture was cooled and partitionedbetween dichloromethane and water. The organic layer was separated, washed three times with water and dried (MgSO 4 ). Evaporation of the solvent gave an oil which was chromatographed on silica gel. Elution with dichloromethane/hexane (1:1) first gave impurity followed by pure product.The product fractions were evaporated and the residue was triturated with ether to give the title compound (6.60 g), m.p. 135°-136° C.Found: C,77.98; H,6.10; N,4.71. C 19 H 17 NO 2 requires: C,78.33; H,5.88; N,4.81%. Further elution with dichloromethane/hexane (4:1) gave benzyl (E)-3-(2-methyl-1H-indol-6-yl)-2-propenoate (2.0 g), m.p. 164°-165° C. Found: C,78.53; H,6.06; N,4.74. C 19 H 17 NO 2 requires: C,78.33; H,5.88; N,4.81%.
The following compounds were prepared similarly.
__________________________________________________________________________Structure m.p. °C. Analytical Data__________________________________________________________________________ ##STR23## 139-141 Found: C, 77.74; H, 5.92; N, 4.52; C.sub.19 H.sub.17 NO.sub.2 requires: C, 78.33; H, 5.88; N, 4.81%. ##STR24## 160-161 Found: C, 75.47; H, 6.46; N, 8.33; C.sub.21 H.sub.22 N.sub.2 O.sub.2 requires: C, 75.42; H, 6.63; N, 8.38%. ##STR25## 121-124 Found: C, 75.53; H, 6.87; N, 8.12; C.sub.22 H.sub.24 N.sub.2 O.sub.2 requires C, 75.83; H, 6.94; N, 8.04%. ##STR26## 146-148 Found: C, 75.12; H, 6.40; N, 8.29; C.sub.21 H.sub.22 N.sub.2 O.sub.2 requires: C, 75.42; H, 6.63; N, 8.38%.__________________________________________________________________________
PREPARATION 11
Benzyl (E)-3- 2-methyl-3-(3-pyridylmethyl)-1H-indol-4-yl!-2-propenoate
A solution of benzyl (E)-3- 2-methyl-1H-indol-4-yl!-2-propenoate (4.75 g) and pyridine-3-carboxaldehyde (2.10 g) in dry dichloromethane (45 ml) was added dropwise to a stirred solution of triethylsilane (7.82 ml) in trifluoroacetic acid (40 ml) at 0° C. The solution was stirred, allowing the temperature to rise to room temperature, for 45 minutes and then evaporated. The residue was partitioned between dichloromethane and dilute aqueous ammonia solution. The aqueous layer was extracted with dichloromethane, and the combined organic layers were washed with water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel. Elution with dichloromethane gave impurity,and further elution with dichloromethane/methanol (19:1) gave pure product.The product fractions were evaporated and the residue was triturated with ether to give the title compound (2.19 g), m.p. 180°-182° C., Rf. 0.35(SS1).
δ(CDCl 3 ): 2.43(3H,s), 4.21(2H,s), 5.21(2H,s), 6.30(1H,d), 7.01-7.11(2H,m), 7.28-7.42(8H,m), 8.19(1H,d), 8.22(1H,s), 8.38(2H,s).
PREPARATION 12
Benzyl (E)-3- 3-(dimethylaminomethyl)-2-methyl-1H-indol-5-yl!-2-propenoate
Dimethylamine (3.35 ml of 33% solution in methylated spirit) was added to astirred mixture of benzyl (E)-3-(2-methyl-1H-indol-5-yl)-2-propenoate (6.50g) in a mixture of acetic acid (14 ml) and tetrahydrofuran (15 ml) at 0° C., followed by the dropwise addition of formaldehyde (1.75 ml of 40% aqueous solution). The mixture was stirred at room temperature for 3 hours and then diluted with ethyl acetate. 2N sodium hydroxide was addeddropwise with stirring until the pH of the aqueous layer was ca.9. The mixture was filtered, and the residue was washed with water followed by ethyl acetate and then dried to give the title compound (6.58 g), m.p. 174°-177° C. Found: C,75.85; H,6.83; N,7.53. C 22 H 24 N 2 O 2 requires: C,75.83; H,6.94; N,8.04%.
PREPARATION 13
Benzyl (E)-3- 3-(dimethylaminomethyl)-2-methyl-1H-indol-4-yl!-2-propenoate
Treatment of benzyl (E)-3-(2-methyl-1H-indol-4-yl)-2-propenoate (6.20 g) with dimethylamine (3.2 ml of 33% solution in methylated spirit), and formaldehyde (1.68 ml of 40% aqueous solution) in acetic acid (13 ml) and tetrahydrofuran (15 ml) according to the method of Preparation 12 gave thetitle compound as a foam (7.45 g), Rf. 0.3(SS3).
δ(CDCl 3 ): 2.25(6H,s), 2.37(3H,s), 3.49(2H,s), 5.28(2H,s), 6.48(1H,d) 7.07(1H,dd), 7.22-7.44(7H,m), 8.08(1H,s), 9.07(1H,d).
PREPARATION 14
Benzyl (E)-3- 3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indol-5-yl!-2-propenoate
A mixture of benzyl (E)-3- (3-dimethylaminomethyl)-2-methyl-1H-indol-5-yl!-2-propenoate (7.65 g) and imidazole (1.64 g) in dry dioxan (50 ml) was heated under reflux for 4 hours. The solution was cooled, filtered and evaporated. The residuewas chromatographed on silica gel using dichloromethane/methanol (19:1) as eluent. Evaporation of the product fractions and trituration of the residue with ether gave the title compound (4.85 g), m.p. 120°-122° C. Found: C,74.43; H,5.70; N,11.25. C 23 H 21 N 3 O 2 requires: C,74.37; H,5.70; N,11.32%.
PREPARATION 15
Benzyl (E)-3- 3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indol-4-yl!-2-propenoate
A mixture of benzyl (E)-3- (3-dimethylaminomethyl)-2-methyl-1H-indol-4-yl!-2-propenoate (7.45 g), and imidazole (1.57 g) in xylene (50 ml) was heated under reflux for 6hours and the solution was evaporated. The residue was chromatographed on silica gel using dichloromethane/methanol as eluent. Evaporation of the product fractions and trituration of the residue with ether gave the titlecompound (3.85 g), m.p. 207°-208.5° C. Found: C,74.48; H,5.64; N,11.31. C 23 H 21 N 3 O 2 requires: C,74.37; H,5.70; N,11.32%.
PREPARATION 16
Methyl 5-nitro-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Benzyltrimethylammonium hydroxide (0.8 ml of 40% solution in methanol) was added to a stirred mixture of 5-nitro-3-(3-pyridylmethyl)-1H-indole (7.34 g) and methyl acrylate (3.0 g) in dioxan (140 ml) and the resulting solution was stirred for 75 minutes and then evaporated. The residue was partitioned between water and ethyl acetate. The aqueous layer was separated and extracted with ethyl acetate. The organic layers were combined, washed with water and dried (Na 2 SO 4 ). Evaporation of the solvent gave a solid which was crystallised from ethyl acetate/hexane to give the title compound (7.33 g), m.p. 101°-102° C. Found: C,63.85; H,4.86; N,12.37. C 18 H 17 N 3 O 4 requires: C,63.71; H,5.05; N,12.38%.
The following compounds were prepared similarly.
__________________________________________________________________________ ##STR27## m.p.R.sup.1 R.sup.2 Y °C. Analytical Data__________________________________________________________________________1-imidazolyl H 5-Nitro 152-154 Found: C, 58.88; H, 5.01; N, 17.07; C.sub.16 H.sub.16 N.sub.4 O.sub.4 requires: C, 58.53; H, 4.91; N, 17.07%.1-imidazolyl CH.sub.3 5-Nitro 150-151 Found: C, 59.82; H, 5.28; N, 16.41; C.sub.17 H.sub.18 N.sub.4 O.sub.4 requires: C, 59.64; H, 5.30; N, 16.37%.1-imidazolyl CH.sub.3 5-(E)-PhCH.sub.2 O.sub.2 CCHCH 113-116 Found: C, 70.97; H, 5.95; N, 9.12; C.sub.12 H.sub.27 N.sub.3 O.sub.4 requires: C, 70.88; H, 5.95; N, 9.19%.1-imidazolyl CH.sub.3 4-(E)-PhCH.sub.2 O.sub.2 CCHCH -- Found: C, 70.88; H, 5.90; N, 8.91; C.sub.27 H.sub.27 N.sub.3 O.sub.4 requires: C, 70.88; H, 5.95; N, 9.19%.3-pyridyl H 5-(E)-t-BuO.sub.2 CCHCH -- Found: C, 71.04; H, 6.67; N, 6.43; C.sub.25 H.sub.28 N.sub.2 O.sub.4 requires: C, 71.40; H, 6.71; N, 6.66%.3-pyridyl H 4-(E)-t-BuO.sub.2 CCHCH 86-88 Found: C, 71.69; H, 6.59; N, 6.77; C.sub.25 H.sub.28 N.sub.2 O.sub.4 requires: C, 71.40; H, 6.71; N, 6.66%.3-pyridyl CH.sub.3 5-(E)-t-BuO.sub.2 CCHCH 91-93 Found: C, 72.17; H, 6.96; N, 6.42; C.sub.26 H.sub.30 N.sub.2 O.sub.4 requires: C, 71.86; H, 6.96; N, 6.45%.3-pyridyl CH.sub.3 4-(E)-t-BuO.sub.2 CCHCH -- Found: C, 74.34; H, 6.07; N, 6.05; C.sub.29 H.sub.28 N.sub.2 O.sub.4 requires: C, 74.37; H, 6.03; N, 5.98%.__________________________________________________________________________
PREPARATION 17
Ethyl 5-nitro-3-(3-pyridyl)-1H-indole-1-butanoate
5-Nitro-3-(3-pyridyl)-1H-indole (0.60 g) was added portionwise to a stirredsuspension of sodium hydride (0.11 g of 60% dispersion in mineral oil) in dry N,N-dimethylformamide (10 ml) at room temperature, and the mixture wasstirred for 30 minutes. Ethyl 4-bromobutanoate (0.40 g) was added and the mixture was stirred for 18 hours. Further sodium hydride (0.11 g of 60% dispersion) was added, the mixture was stirred for 30 minutes and then further ethyl 4-bromobutanoate (0.40 g) was added. Stirring was continued for an additional 4 hours and then the mixture was partitioned between ethyl acetate and water. The organic layer was separated, washed twice with water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed using dichloromethane/methanol (100:1) as eluent. The product fractions were combined and evaporated, and the residue was triturated with ether to give the title compound (0.51 g), m.p. 76°-78° C. Found: C,64.92; H,5.48; N,11.95. C 19 H 19 N 3 O 4 requires: C,64.58; H,5.42; N,11.89%.
PREPARATION 18
Methyl 5-nitro-3-(3-pyridyl)-1H-indole-1-propanoate
Benzyltrimethylammonium hydroxide (0.17 ml of 40% solution in methanol) wasadded to a stirred suspension of 5-nitro-3-(3-pyridyl)-1H-indole (0.95 g) and methyl acrylate (0.41 g) in a mixture of tetrahydrofuran (10 ml) and dioxan (15 ml), and the mixture was stirred at room temperature for 2 hours. Methanol (10 ml) was added to give a clear solution followed by further methyl acrylate (0.41 g) and benzyltrimethylammonium hydroxide solution (0.17 ml) and stirring was continued for an additional 18 hours. Potassium t-butoxide (100 mg) was added and stirring was continued for a further 6 hours and the solution was evaporated. The residue was partitioned between ethyl acetate and water and the organic layer was separated and dried (MgSO,). Evaporation of the solvent gave a solid whichwas crystallised from dichloromethane/hexane to give the title compound (0.48 g), m.p. 123°-125° C. Found: C,62.85H,4.62; N,12.91. C 17 H 15 N 3 O 4 requires: C,62.76; H,4.65; N,12.92%.
PREPARATION 19
Methyl 3-(4-fluorophenylmethyl)-5-nitro-1H-indole-1-propanoate
Tetrabutylammonium bromide (0.262 g) and potassium t-butoxide (100 mg) wereadded to a stirred solution of 3-(4-fluorophenylmethyl)-5-nitro-1H-indole (2.20 g) and methyl acrylate (0.84 g) in dioxan (30 ml) and the solution was stirred at room temperature for 66 hours. Further quantities of methylacrylate (0.5 g), tetrabutylammonium bromide (262 mg) and potassium t-butoxide (100 mg) were added and stirring was continued for an additional 5 hours. The solution was poured into water and the mixture wasextracted twice with ether. The combined ether extracts were washed with water, dried (Na 2 SO 4 ) and evaporated. The residue was chromatographed on silica gel using hexane/dichloromethane (1:4) as eluent. The product fractions were combined and evaporated to give the title compound as a gum (1.90 g). Found: C,64.43; H,4.39; N,7.65. C 19 H 17 FN 2 O 4 requires: C,64.03; H,4.81; N,7.86%.
PREPARATION 20
Methyl 5-nitro-1H-indole-1-propanoate
Reaction of 5-nitro indole (3.0 g) with methyl acrylate (2.29 g) in the presence of potassium t-butoxide (0.258 g) and tetrabutylammonium bromide according to the method of Preparation 19 gave the title compound (3.0 g),m.p. 97°-99° C. Found: C,57.86; H,4.84; N,10.78. C 12 H 12 N 2 O 4 requires: C,58.06; H,4.87; N,11.28%.
PREPARATION 21
Methyl 5-(2-carboxyethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate
A solution of benzyl (E)-3- 3-(1H-imidazol-1-ylmethyl)-1-(2-methoxycarbonylethyl)-2-methyl-1H-indol-5-yl!-2-propenoate (2.0 g) in tetrahydrofuran (40 ml) was hydrogenatedat room temperature and 4.5 atm. in the presence of 10% palladium on carbon(0.20 g) until reaction was complete (5 hours). The mixture was filtered and the residue was washed with ethyl acetate. The combined filtrate and washings were evaporated and the residue was triturated with ether to givethe title compound (1.52 g), m.p. 134°-137° C. Found: C,65.31; H,6.35; N,10.70. C 20 H 23 N 3 O 4 requires: C,65.02; H,6.28N,11.38%.
PREPARATION 22
Methyl 4-(2-carboxyethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate
Hydrogenation of benzyl (E)-3- 3-(1H-imidazol-1-ylmethyl)-1-(2-methoxycarbonylethyl)-2-methyl-1H-indol-4-yl!-2-propenoate (1.40 g) in the presence of 10% palladium on carbon(0.15 g) according to the method of Preparation 21 gave the title compound (0.82 g), m.p. 136°-138° C.
δ(DMSOd 6 ): 2.34(2H,t), 2.57(3H,s), 2.74(2H,t), 2.96(2H,t), 3.54(3H,s), 4.40(2H,t), 5.32(2H,s), 6.78(1H,d), 6.82(1H,s), 6.90(1H,s), 6.98(1H,dd), 7.29(1H,d), 7.43(1H,s).
PREPARATION 23
t-Butyl 1-(2-methoxycarbonylethyl)-3-(3-pyridylmethyl)-1H-indole-5propanoate
A mixture of t-butyl (E)-3- 1-(2-methoxycarbonylethyl)-3-(3-pyridylmethyl)-1H-indol-5-yl!-2-propenoate (7.86 g), 10% palladium on carbon (0.70 g) and ammonium formate (5.60 g) in a mixture of methanol (40 ml) and tetrahydrofuran (40 ml) was heated at 60° C. for 3 hours and then cooled. The mixture was filtered and the residue was washed with methanol. The filtrate and washings were combined and evaporated, and the residue-was partitioned between water and ether. The organic layer was separated and the aqueous layer was extracted with ether. The organic layers were combined, washed with water and dried (MgSO 4 ). Evaporation of the solvent gave the title compound as an oil (7.80 g). Found: C,70.51; H,6.98; N,6.54. C 25 H 30 N 2 O 4 requires: C,71.06; H,7.16; N,6.63%.
PREPARATION 24
t-Butyl 1-(2-methoxycarbonylethyl)-3-(3-pyridylmethyl)-1H-indole-4-propanoate
Treatment of t-butyl (E)-3- 1-(2-methoxycarbonylethyl)-3-(3-pyridylmethyl)-1H-indole-4-yl!-2-propenoate (5.15 g) with 10% palladium on carbon (0.50 g) and ammonium formate (7.71 g) according to the method of Preparation 23 gave the title compound, (4.67 g) m.p. 80°-82° C. Found: C,71.43; H,7.06; N,6.35. C 25 H 30 N 2 O 4 requires: C,71.06; H,7.16; N,6.63%.
PREPARATION 25
Methyl 5-(2-carboxyethyl)-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Trifluoroacetic acid (15 ml) was added to a stirred solution of t-butyl 1-(2-methoxycarbonylethyl)-3-(3-pyridylmethyl)-1H-indole-5-propanoate (7.60 g) in dry dichloromethane (100 ml) at room temperature, and stirringwas continued for 18 hours. The solution was evaporated and the residue wasazeotroped with toluene and then dissolved in ethyl acetate. Saturated sodium bicarbonate solution was added slowly with shaking until the pH of the aqueous layer was 4-5. The organic layer was then separated, washed with water and dried (MgSO 4 ). The solvent was evaporated and the residue was triturated with ether to give the title compound (5.70 g), m.p. 108°-110° C. Found: C,68.80; H,6.16; N,7.57%. C 21 H 22 N 2 O 4 requires: C,68.83; H,6.05; N,7.65%.
The following compounds were prepared similarly from the corresponding t-butyl ester.
__________________________________________________________________________Structure m.p. °C. Analytical Data__________________________________________________________________________ ##STR28## 199-201 Found: C, 68.65; H, 6.27; N, 7.53. C.sub.21 H.sub.22 N.sub.2 O.sub.4 requires: C, 68.83; H, 6.05; N, 7.65%. ##STR29## 180-182 Found: C, 69.65; H, 5.73; N, 7.19. C.sub.22 H.sub.22 N.sub.2 O.sub.4 requires: C, 67.82; H, 5.86; N,__________________________________________________________________________ 7.40%.
PREPARATION 26
Methyl 5-(2-carboxyethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate
A mixture of (E)-3- 1-(2-methoxycarbonylethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indol-5-yl!-2-propenoic acid (2.02 g), 10% palladium on carbon (0.20 g) and ammonium formate (1.68 g) in methanol (20 ml) and tetrahydrofuran (20 ml) was heated at 60° C. for 4 hours and then cooled and filtered. The residue was washed with methanol, and the filtrate and washings were combined and evaporated. The residue was triturated with dilute acetic acid to give a gummy solid. The solid was filtered off and boiled with ether to give the title compound as a crystalline solid (1.79 g), m.p. 144°-146° C. Found: C,69.60; H,6.20; N,7.16. C 22 H 24 N 2 O 4 requires: C,69.45; H,6.36; N,7.37%.
PREPARATION 27
Methyl 4-(2-carboxyethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Treatment of benzyl 1-(2-methoxycarbonylethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate (6.45 g) with palladium on carbon (0.65 g) and ammonium formate (8.90 g) according to the method of Preparation 26 gave the title compound (3.76g). m.p. 165°-167° C. Found: C,69.43; H,6.42; N,7.37. C 22 H 24 N 2 O 4 requires: C,69.45; H,6.36; N,7.37%.
PREPARATION 28
Methyl 5-(2-benzyloxycarbonylaminoethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate
Diphenylphosphoryl azide (0.744 g) was added to a mixture of methyl 5-(2-carboxyethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate (1.0 g) and triethylamine (0.274 g) in dry dioxan (5 ml) at 50° C. The solution was then heated at 100° C. for 1 hour to give a clear solution. Benzyl alcohol (0.352 g) was added and the solution was heated at 1000° C. for a further 20 hours and then evaporated. The residue was partitioned between ethyl acetate and sodium bicarbonate solution. The organic layer was separated, washed with brine and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel using dichloromethane/methanol (97:3) as eluent. The product fractions were combined and evaporated to give the title compound as a gum (0.41 g). Found: C,68.12; H,6.41; N,11.23. C 27 H 30 N 4 O 4 requires: C,68.33; H,6.37; N,11.81%.
The following compounds were prepared similarly using either benzyl alcoholor t-butanol.
__________________________________________________________________________Structure m.p. °C. Analytical Data__________________________________________________________________________ ##STR30## Gum Rf. 0.4(SS4). δ(CDCl.sub.3): 1.46(9H, s), 2.82(2H, t), 2.89(2H, t), 3.42(2H, m), 3.67(3H, s), 4.08(2H, s), 4.41(2H, t), 4.58(1H, br), 6.84(1H, s), 7.08(1H, d), 7.22(1H, m), 7.28- 7.32(2H, m), 7.55(1H, d), 8.47(1H, d), 8.59(1H, s). ##STR31## Gum Rf. 0.5(SS3). δ(CDCl.sub.3): 1.44(9H, s), 2.80(2H, t), 2.99(2H, t), 3.32(2H, m), 2.65(3H, s), 4.15(2H, s), 4.38(2H, t), 4.57(1H, br), 6.75(1H, s), 6.87(1H, d), 7.16-7.22(3H, m), 7.45(1H, d), 8.44(1H, d), 8.50(1H, s). ##STR32## 127.5- 129.5 Found: C, 68.15; H, 6.42; N, 11.77. C.sub.27 H.sub.30 N.sub.4 O.sub.4 requires: C, 68.33; H, 6.37; N, 11.81%.__________________________________________________________________________
PREPARATION 29
Methyl 5-(2-t-butoxycarbonylaminoethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Diphenylphosphoryl azide (3.99 g) was added to a stirred mixture of methyl 5-(2-carboxyethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate (5.00 g) and triethylamine (1.46 g) in dry t-butanol (30 ml) and the mixture was heated at 100° C. for 18 hours and then evaporated. Theresidue was dissolved in dichloromethane, and the solution was washed twicewith water and dried (MgSO 4 ). The solvent was evaporated and the residue was chromatographed on silica gel. Elution with dichloromethane and evaporation of the product fractions gave the title compound as a gum (4.51 g), Rf. 0.35(SS4). δ(CDCl 3 ): 1.42(9H,s), 2.37(3H,s), 2.73(2H,t), 2.82(2H,t), 3.36(2H,m), 3.68(3H,s), 4.05(2H,s), 4.39(2H,t), 4.50(1H,br), 7.00(1H,d), 7.10-7.25(3H,m) 7.41 (1H,d), 8.39(1H,d), 8.50(1H,s).
PREPARATION 30
Methyl 4-(2-t-butoxycarbonylaminoethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Treatment of methyl 4-(2-carboxyethyl)-2-methyl-3-(3-pyridylmethyl)-1H-indole-1-propanoate (3.70 g) with diphenylphosphoryl azide (2.95 g), triethylamine (1.08 g), and t-butanol (30 ml) as described in Preparation 29 gave the title compound as an oil (3.46 g), Rf. 0.5 (SS2). δ(CDCl 3 ): 1.44(9H,s), 2.37(3H,s), 2.77(2H,t), 2.87(2H,t), 3.23(2H,m), 3.68(3H,s), 4.28(2H,s), 4.45(2H,t), 4.53(1H,br), 6.82(1H,d), 7.10-7.13(2H,m), 7.21(1H,d), 7.29(1H,d), 8.38-8.42(2H,m).
PREPARATION 31
Methyl 5-amino-3-(3-pyridylmethyl)-1H-indole-1-propanoate
A mixture of methyl 5-nitro-3-(3-pyridylmethyl)-1H-indole-1-propanoate (1.20 g) and 10% palladium on carbon (120 mg) in methanol (75 ml) was hydrogenated at 50° C. and 4.5 atm. until reduction was complete (2hours). The mixture was filtered and the catalyst was washed well with methanol. The filtrate and washings were combined and evaporated to give the title compound as an oil (1.05 g), Rf. 0.2(SS2). δ(CDCl 3 ): 2.76(2H,t), 3.45(2H,br), 3.63(3H,s), 3.98(2H,s), 4.32(2H,t), 6.66-6.68(1H,dd), 6.72(1H,d), 6.77(1H,s), 7.11(1H,d), 7.14-7.18(1H,m), 7.48-7.51(1H,m), 8.42-8.44(1H,m), 8.56(1H,d).
The following compounds were prepared similarly as oils.
__________________________________________________________________________ ##STR33##R.sup.1 X R.sup.2 m R.sup.7 Analytical Data__________________________________________________________________________1-imidazolyl CH.sub.2 H 2 CH.sub.3 Rf. 0.7(SS5). δ(CDCl.sub.3): 2.83(2H, t), 3.47(2H, br), 3.67(3H, s) 4.38(2H, t), 5.19(2H, s), 6.68(1H, d), 6.71-6.74(1H, dd), 6.96(1H, s), 7.06(1H+1H, s), 7.15(1H, d), 7.59(1H, s).1-imidazolyl CH.sub.2 CH.sub.3 2 CH.sub.3 Rf. 0.4(SS2). δ(CDCl.sub.3): 2.42(3H, s), 2.77(2H, t), 3.50(2H, br), 3.68(3H, s), 4.39(2H, t), 5.16(2H, s), 6.63-6.69(2H, m), 6.93(1H, s), 7.05(1H, s), 7.14(1H, d), 7.54(1H, s).4-fluorophenyl CH.sub.2 H 2 CH.sub.3 Rf. 0.4(SS6). δ(CDCl.sub.3): 2.77(2H, t), 3.42(2H, br), 3.65(1H, s), 3.97(1H, s), 4.33(2H, t), 6.67(1H, dd), 6.68- 6.69(2H, d+s), 6.95(2H, t), 7.12(1H, d), 7.17- 7.22(2H, m).3-pyridyl direct H 2 CH.sub.3 Rf. 0.2(SS2). link δ(CDCl.sub.3): 2.85(2H, t), 3.65(2H, br), 3.67(3H, s), 4.44(2H, t), 6.75(1H, dd), 7.18(1H, d), 7.27(1H, s), 7.27(1H, d), 7.30-7.34(1H, m), 7.87(1H, m), 8.47(1H, dd), 8.86(d).3-pyridyl direct H 3 C.sub.2 H.sub.5 Rf. 0.2(SS2). link δ(CDCl.sub.3): 1.24(3H, t), 2.15(2H, m), 2.32(2H, t), 3.45(2H, br), 4.11(2H, t), 4.19(2H, t), 7.18-7.23(3H, m), 7.30-7.35(1H, m), 7.89(1H, m), 8.47(1H, dd), 8.86(1H, dd).H direct H 2 CH.sub.3 Rf. 0.25(SS6). link δ(CDCl.sub.3): 2.80(2H, t), 3.35(2H, br), 3.67(2H, s), 4.39(2H, t), 6.30(1H, d), 6.68(1H, dd), 6.93(1H, d), 7.04(1H, d), 7.14(1H, d).__________________________________________________________________________
PREPARATION 32
Methyl 5-(2-aminoethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoat
A solution of methyl 5-(2-benzyloxycarbonylaminoethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate (0.57 g) in tetrahydrofuran (50 ml) was hydrogenated at room temperature and 4.5 atm. pressure in the presence 10% palladium on carbon (50 mg) for 20 hours. The mixture was filtered and the residue was washed with methanol. The filtrate and washings were combined and evaporated to give a gum which was chromatographed on silica gel. Elution with dichloromethane/methanol (19:1) gave impurity, and then further elution with dichloromethane/methanol/0.880 ammonia solution (95:5:1) gavepure product. The product fractions were evaporated to give the title compound as a gum (0.325 g), Rf. 0.4 (SS3). The product was used directly for further reaction.
PREPARATION 33
Methyl 4-(2-aminoethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate
Hydrogenation of methyl 4-(2-benzyloxycarbonylaminoethyl)-3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoate (0.50 g) in tetrahydrofuran (20 ml) in the presence of 10% palladium on carbon (100 mg+a further 50 mg quantities after 24 and 48hours) for 72 hours, followed by work up as described for Preparation 32 gave the title compound as a gum (0.20 g), Rf. 0.15(SS3). δ(CDCl 3 ): 1.70(2H,br), 2.47(3H,s), 2.81(2H,t), 2.88(4H,s), 3.70(3H,s), 4.48(2H,t), 5.37(2H,s), 6.86(1H,s), 6.95(1H,d), 7.04(1H,s), 7.17(1H,m), 7.24(1H,d), 7.42(1H,s).
PREPARATION 34
Methyl 5-(2-aminoethyl)-3-(3-pyridylmethyl)-1H-indole-1-propanoate
Trifluoroacetic acid (5 ml) was added to a stirred solution of methyl 5-(2-t-butoxycarbonylaminoethyl)-3-(3-pyridylmethyl)-1H-indole -1-propanoate (5.0 g) in dry dichloromethane (50 ml) and the solution was stirred for 3 hours. An additional 5 ml of trifluoroacetic acid was then added and stirring was continued for a further 2 hours. The solution was evaporated and the residue was partitioned between dichloromethane and dilute aqueous ammonia. The aqueous layer was separated and extracted withdichloromethane. The organic layers were combined and evaporated. Water (ca50 ml) was added followed by sufficient acetic acid to adjust the pH to ca4. The solution was washed twice with ethyl acetate and then made basic with concentrated aqueous ammonia solution. The mixture was extracted twice with dichloromethane and the combined extracts were dried (MgSO 4 ) and evaporated to give the title compound as a gum (2.51 g), Rf. 0.15(SS3).
(CDCl 3 ): 1.39(2H,s), 2.80-2.86(4H,m), 2.98(2H,t), 3.67(3H,s), 4.08(2H,s), 4.42(2H,t), 6.83(1H,s), 7.08(1H,d), 7.20(1H,m), 7.27-7.29(2H,m), 7.54(1H,d), 8.45(1H,d), 8.59(1H,s).
The following compounds were prepared similarly.
__________________________________________________________________________Structure Analytical Data__________________________________________________________________________ ##STR34## Rf. 0.4(SS5). δ(CDCl.sub.3): 1.47(2H, s), 2.38(3H, s), 2.71-2.80(4H, m), 2.92(2H, t), 3.66(3H, s), 4.04(2H, s), 4.40(2H, t), 7.00(1H, d), 7.11(1H, m), 7.18(1H, s), 7.22(1H, d), 7.40(1H, d), 8.36(1H, d), 8.52(1H, s). ##STR35## Rf. 0.45(SS3). δ(CDCl.sub.3): 1.08(2H, br), 2.77(2H, t), 2.88-2.97(4H, m), 3.65(3H, s), 4.22(2H, s), 4.35(2H, t), 6.69(1H, s), 6.87(1H, d), 7.12-7.26(3H, m), 7.45(1H, d), 8.45(1H, d), 8.51(1H, s). ##STR36## Rf. 0.4(SS3). δ(CDCl.sub.3): 2.37(3H, s), 2.76(2H, t), 2.85(2H, t), 2.97(2H, t), 3.68(3H, s), 4.21(2H, s), 4.30(2H, br), 4.44(2H, t), 6.82(1H, d), 7.05-7.11(2H, m), 7.20(1H, d), 7.24-7.26(1H, m), 8.31(1H, d), 8.45(1H, s).__________________________________________________________________________ | Compounds of formula (I): ##STR1## and pharmaceutically acceptable salt and biolabile esters thereof, wherein R 1 is H, C 1 -C 4 alkyl, phenyl optionally substituted by up to three substituents independently selected from C 1 -C 4 alkyl, C 1 -C 4 alkoxy, halogen and CF 3 , or is 1-imidazolyl, 3-pyridyl or 4-pyridyl; R 2 is H or C 1 -C 4 alkyl, R 3 is SO 2 R 4 or COR 4 where R 4 is C 1 -C 6 alkyl, C 1 -C 3 perfluoroalkyl(CH 2 ) p , C 3 -C 6 cycloalkyl(CH 2 ) p , aryl(CH 2 ) p , or heteroaryl(CH 2 ) p , p being 0, 1 or 2, or R 4 may be NR 5 R 6 where R 5 is H or C 1 -C 4 alkyl and R 6 is C 1 -C 6 , alkyl, C 3 -C 6 cycloalkyl or aryl, or R 5 and R 6 together with the nitrogen atom to which they are attached form a 5- to 7-membered heterocyclic ring which may optionally incorporate a carbon-carbon double bond or a further heteroatom linkage selected from O, S, NH, N(C 1 -C 4 alkyl) and N(C 1 -C 5 alkanoyl); X is CH 2 or a direct link, with the proviso that when R 1 is 1-imidazolyl then X is CH 2 ; m is 2, or 3; n is 0, 1 or 2, and wherein the group (CH 2 ) n NHR 3 is attached at the 5-position when n is 0 or 1, or at the 5- or 4-position when n is 2. These compounds are selective TXA 2 and PGH 2 antagonists. Some also inhibit thromboxane synthetase. | 2 |
INTRODUCTION
Numerous stands have been provided for mounting cut trees, such as Christmas trees; however, these stands have not been without problems. For example, if the lower portion of the tree trunk is bent or bowed, often it is very difficult to mount the tree vertically. Or, if the tree is mounted vertically, it is only with a great amount of trial and error.
In the art, U.S. Pat. No. 4,156,323 discloses a tree supporting stand having a central support member mounting a plurality of radially extending legs, each of which is adapted to engage a horizontal surface for supporting a tree.
U.S. Pat. No. 3,231,227 discloses an adjustable tree support to make allowances for curvature in tree trunks and to actually hold tree trunks in a vertical position.
U.S. Pat. No. 3,779,493 discloses a stand for trees, particularly means to secure the tree in a water container to take various positions of inclination. A ball joint is provided to permit adjustment of the alignment of the water container relative to the base supporting the tree.
U.S. Pat. No. 4,699,347 discloses a a Christmas tree stand having a circular base and three legs extending upward in tripod form to an apex where a clamping mechanism is located. A ball is securely held between a claim base located atop one leg and a clamp top. An elongated member pivots on the socket leg, and the tree can be adjusted to the vertical position.
U.S. Pat. No. 4,571,882 discloses a tree stand which permits a tree, if deformed or if placed in the stand at an angle, to be aligned in a perpendicular position with respect to any type of floor, whether it be irregular or uneven. The receptacle for retaining the tree is formed integral therewith a hemispherical ball which is received by two adjustable jaws which form a hemispherical cavity.
The present invention overcomes the problems encountered in prior tree stands and permits mounting and securing the tree in a vertical position with ease.
SUMMARY OF THE INVENTION
Disclosed is an improved tree stand for holding a tree trunk to position a tree in a substantially vertical position. The tree stand is comprised of a base member having a clamp means positioned on the base member, a tree trunk holder having a sleeve for receiving the tree trunk. The sleeve has a circumferential band thereon which has a substantially circular outer surface. A clamp means is attached to the base member and is designed to receive the circumferential band and to permit the tree trunk holder to swivel prior to being clamped in position.
It is, therefore, an object of this invention to provide an improved tree stand.
It is yet another object of this invention to provide an improved tree stand having a tree trunk holder which permits ease of positioning a cut tree in the vertical position even when the tree trunk is bent or crooked.
Yet another object is to provide a tree stand having an adjustable tree trunk holder.
These and other objects of the invention will be understood from the following description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the tree stand showing a tree trunk holder and base.
FIG. 2 is an elevational view of the tree trunk holder.
FIG. 3 is an elevational view of the base.
FIG. 4 is a cross-sectional view of the base and tree trunk holder showing water in the base.
FIG. 5 is a top view of the base along the line 5--5.
FIG. 6 is a top view of the tree trunk holder along the line 4--4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view of the tree stand 10 showing a circular base 12 having side wall 14 and collar 20. Collar 20 has a screw mechanism 24 which can be turned to clamp tightly around a tree trunk holder referred to generally as 30. Tree trunk holder 30 (FIGS. 2 and 6) comprises a sleeve-shaped portion 34 and has fasteners 32 for gripping the tree trunk upon its insertion into the sleeve-shaped portion. As can be seen in FIG. 2, sleeve-shaped portion 34 has a circumferential band 36 rigidly attached to sleeve-shaped portion 34. Band 36 is positioned on sleeve-shaped portion 34 to enable a part 38 of sleeve-shaped portion 34 to project into base 12 as seen in FIG. 4. In addition, sleeve-shaped portion 34 preferably has a part thereof which projects above band 36 to enable fastening of the trunk in the sleeve portion. Further, preferably sleeve portion has an end 40 which is tapered sufficiently inwardly to prevent the tree trunk from slipping through the sleeve portion. That is, tapered end 40 serves as a stop and prevents the tree trunk from resting on bottom 42 which would interfere with adjusting the tree into the vertical position, thereby defeating the purpose of the present invention.
Circumferential band 36 is generally circular and has an outer surface 44 which is curved or arched as shown. Preferably, surface 44 is curved to form a sector of a circle. As shown in FIG. 3, collar 20 has an interior surface 48 which is curved inwardly at lower section 50. That is, the inside diameter of collar 20 at lower extremity 50 is smaller than the inside diameter of collar 20 at upper extremity 51. The dimensions of band 36 should be such to permit the band to fit snugly in collar 20, as shown in FIG. 4. Surface 44 should be rounded or curved as noted to permit sleeve-shaped portion 34 to swivel or tilt from a vertical axis, as shown in FIG. 1, for example. Lower section 50 acts as a stop and as a bearing surface against band surface 44, thereby permitting sleeve-shaped portion 34 to be rotated when the tree trunk is inserted into the sleeve portion.
Collar 20 has a clamp means to secure band 36. The clamp shown is a screw mechanism 24 which serves to tighten collar 20 about circumferential band 36 whenever the tree has been placed in a desirable vertical position. Preferably, collar 20 is securely fastened at one point by welding, for example, so as to permit collar 20 to adjust and clamp band 36 firmly.
In using the adjustable stand, sleeve-shaped portion 34 may be removed from the base and the sleeve portion mounted on the tree trunk. The sleeve portion can be securely fastened to the trunk with screws 32 without the need for precisely centering the tree trunk within the sleeve portion. The sleeve portion containing the trunk is then placed in collar 20 and the tree rotated to a vertical position where it is then clamped using screw mechanism 24.
The adjustable tree stand has the added advantage that base 12 serves as a container for water 54 to keep the tree in fresh condition. An opening for adding water to the base may be provided in wall 14.
Further, the adjustable tree stand, including base and sleeve portion, can be fabricated or formed from plastic material, steel or aluminum, or like materials.
While the invention has been described with respect to embodiments and configurations shown in the drawings, it will be appreciated that other embodiments and configurations may be used which employ the spirit of the invention, and such is contemplated within the purview of the invention. | This invention relates to stands for cut trees, such as Christmas trees, and more particularly, it relates to a tree stand which permits the tree to be mounted vertically even when the tree trunk is bent. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of pending U.S. application Ser. No. 11/472,132, filed on Jun. 20, 2006, which claims the benefit of priority under 35 USC §119(e) to U.S. Provisional Application No. 60/779,654, filed on Mar. 7, 2006; U.S. Provisional Application No. 60/796,185, filed on May 1, 2006; U.S. Provisional Application No. 60/801,395, filed on May 19, 2006; U.S. Provisional Application No. 60/809,831, filed on Jun. 1, 2006; and U.S. Provisional Application No. 60/814,537, filed on Jun. 19, 2006; this application also claims the benefit of priority under 35 USC §119(e) to U.S. Provisional Application No. 60/843,393, filed on Sep. 11, 2006, and U.S. Provisional Application No. 60/842,667, filed on Sep. 7, 2006.
[0002] All of the above applications are incorporated herein by reference in their entirety for all purposes.
TECHNICAL FIELD
[0003] This invention pertains to computerized methods and systems for displaying information on a display associated with a computing device.
BACKGROUND OF THE INVENTION
[0004] Today, a computer user's display is a very busy environment. The typical user has many applications running on their computer. Email, word processing, spreadsheet, instant messaging, calendar, stock portfolio, newsreader, location and even process control. As a user is trying to complete a task, they are focused on one particular application, but the other applications continue to work in the background. These background applications can send notifications to the user's screen at any moment. A user often has to attend to this notification, simply to determine the notification contents. This takes the user away from the task they are focussed on. This is very intrusive. An example is when a user is working on a document in a word processor. They receive an instant message notification that is usually a flashing rectangle at the bottom of their screen and an accompanying audio herald. To determine the contents of the instant message, the user must click on the flashing rectangle at the bottom of the screen, which then expands to an instant messaging conversation window. The user then must minimize the conversation window and return to the word processor application. The instant message notification has notably disrupted the user's work in the word processor application.
[0005] Nawaz in U.S. Pat. No. 6,421,694, teaches the display of notifications in a ticker display pane similar to that illustrated in FIG. 1 a . Ticker panes repeat notifications periodically to increase the chance that a user will see the notification, but unless the user is looking at the ticker pane when a particular notification goes by, they will miss it. Another drawback with ticker panes is that because they repeat notifications periodically, old notifications are sometimes displayed next to new notifications. This lack of time order, in notification display, makes review of historic notifications difficult.
[0006] Email and newsreader programs use notification balloons in the corner of the screen. These notifications are transitory. If a user is not looking at the corner of the screen at the moment of the notification's arrival, the user will miss the notification. If a user is away from their computer while at lunch, they will miss all the notification balloons. Users do not trust that they have seen all their required notification balloons so they resort to manually checking all their applications for fresh notifications. The user checks their email application for the email they are expecting, they check their phone program to see who has called, they check their portfolio program for value of their portfolio, they check their newsgroup program to see if someone has responded to their question. All of this checking takes a lot of effort. To go through this checking cycle a user must click on the email icon to switch to their email inbox, examine their inbox, then click on the phone icon to switch to their phone inbox, examine their phone inbox, then click on the portfolio icon to switch to their portfolio application, examine their portfolio, then click on the newsgroup icon to switch to their newsgroup inbox and so on.
[0007] What is needed is a system and method such that a computer user can monitor a large number of notifications in one place. The display of notifications must not be disruptive to the user's current task. The computer user must be able to act on notifications quickly, easily transitioning to the computer program associated with the notification. The notifications must persist so the computer user can review them at their convenience. The display of the historic notifications must facilitate rapid review by the user.
BRIEF SUMMARY OF THE INVENTION
[0008] In one embodiment, a method of the invention is implemented in a first computer program running on a computing device. The first computer program can also be referred to as the Multi-application Bulletin Board computer program. The computing device is associated with a user.
[0009] The first computer program receives messages (notifications) from plural running computer programs. The messages are received in a non-polled manner, that is to say, the messages are received on an event driven basis without requiring a particular query by the first computer program. The plural running computer programs can be running on the same computing device as the first computer program or some of them can also be running on other computing devices. In addition, the messages are intended to be received by the first computer program.
[0010] Headlines are derived from the received messages and the headlines are integrated into a sequence of headlines. The sequence of headlines is displayed on a display associated with the computing device. The displaying of the sequence of headlines is such that headlines corresponding to more recently received messages are displayed below headlines corresponding to less recently received messages in the plane of the display. The order of the displayed sequence of headlines can also be reversed. The displayed sequence of headlines covers only a small area on the display, thus allowing the user to work in a particular computer program and still see notifications from background computer programs.
[0011] User input directed at the displayed sequence of headlines can cause a message to be posted back to one of the plural running computer programs. For example, if a user clicks on a headline corresponding to an instant message, a message can then be sent to an instant messaging program running on the computing device. The instant messaging program might then bring up a specific conversation window. Another example would be if a user clicks on a headline corresponding to a location notification, a message can then be sent to a location program. The location program might then display more detailed location information on a subject.
[0012] User input directed at the displayed sequence of headlines can also cause a computer program to be launched. An example of this would be if a user clicks on a headline corresponding to a word processor document, a word processing application can then be launched.
[0013] As messages (notifications) are received, headlines are added to the sequence of headlines and the displayed sequence of headlines is updated. This is an improvement over the prior art event viewer in FIG. 1B that only updates in response to user input. In addition, the displayed sequence of headlines can be made to go partially transparent after a period of time with no new headlines or without user interaction. This reduces the effective screen real estate. Also, if a user has been away from their computer for a lunch, upon their return, they can easily scroll the displayed sequence of headlines to review the headlines added during their absence.
[0014] Using the described systems and methods, a computer user does not have to look, click and maneuver through multiple screen areas while keeping on top of their instant messaging, process monitoring, location monitoring and emailing. Using the described system and methods, when a computer user returns to their desk, they can quickly check the displayed sequence of headlines for phone calls, instant messages, location notices or emails they have received during their absence from the computer.
[0015] Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
[0017] FIG. 1 a shows a prior art ticker pane.
[0018] FIG. 1 b illustrates a prior art event log.
[0019] FIG. 2 shows an exemplary block diagram of a system of the invention.
[0020] FIG. 3 a shows an example of a headline.
[0021] FIG. 3 b is an example of a message sent to the first computer program.
[0022] FIG. 3 c is another example of a message sent to the first computer program.
[0023] FIG. 4 a shows an array of received messages
[0024] FIG. 4 b shows an example user interface.
[0025] FIG. 5 a illustrates a method of the invention.
[0026] FIG. 5 b illustrates another method of the invention.
[0027] FIG. 6 shows how the displayed sequence of headlines might appear on a display of a computing device.
[0028] FIG. 7 illustrates what can happen when a user clicks on a headline from a location program.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
[0030] FIG. 2 is a block diagram of a system of the invention. 200 represents a computing device. The computing device is associated with a user. 200 can be any suitable type of computing device examples of which include: cellphone, handheld, PDA, desktop computer and notebook computer. 210 is a first computer program running on the computing device 200 . The first computer program 210 can be any type of computer program such as an application or service or part of an operating system. The first computer program 210 comprises a message receiver 220 , a headline integrator 230 , a user interface 240 , a message sender 250 and a computer program launcher 260 . This illustration of the functional modules of 210 is an example only. Other combinations of functionalities within 210 are possible and fit within the invention.
[0031] 270 is a second computer program running on the computing device 200 . The second computer program 270 can send and receive messages with the first computer program 210 . 280 is a third computer program running external to the computing device 200 . 280 is shown only sending messages to the first computer program 210 , but it could also receive messages from 210 . 290 and 295 are fourth and “nth” computer programs running on the computing device 200 , they are shown only sending messages to the first computer program 210 but they could also receive messages from the first computer program 210 . In one embodiment, there are two or more computer programs sending messages to the first computer program.
[0032] Messages are sent to the first computer program 210 on an event driven basis, with the sending computer programs determining the events which cause a message to be sent as well as the timing of when a message is sent. This is described as the first computer program 210 receiving messages on an event driven basis.
[0033] There are many ways to send and receive messages between running computer programs, a few examples include TCP, HTTP, SOAP, DDE, COM and CORBA. In one embodiment, Hyper Text Transfer Protocol (HTTP) is used to send and receive messages between the running computer programs but certainly any other methodology, such as COM, could be used.
[0034] FIG. 3 a illustrates one example of a headline 300 . A headline 300 comprises at least one word. The time stamp and and icon shown as part of the headline 300 in FIG. 3 a are optional. Also, other elements can be added to the headline 300 and it is still a headline 300 . A headline 300 can have text that extends for several rows, depending on how it is displayed.
[0035] FIG. 3 b is an example of a message 310 that might be sent from the second computer program 270 to the first computer program 210 . In this example, the second computer program 270 is a location application (this is an example only, the second computer program 270 can be any type of computer program). The message 310 is sent as an HTTP PUT request. The HTTP headers are populated with the details of the message 310 . 320 is a headline header that contains the characters of a headline associated with the message 310 . 325 is a postbackstring header that contains a string that can be sent back to the second computer program 270 . 330 is a postbacklistener header that contains the address where the postbackstring can be sent. 335 is the textcolor header that contains a possible color for use in the display of the headline 300 associated with the message 310 . 340 is data in the message which in this case is the binary data of an icon.
[0036] FIG. 3 c is an example of a message 310 that might be sent from the third computer program 280 . 345 is a appname header which contains the name of a computer program that can be launched. 350 is a doclocation header which contains a parameter that can be used when launching the computer program indicated by the appname header 345 .
[0037] FIG. 3 b and FIG. 3 c are examples of messages 310 that can be received by the first computer program 210 . These examples are using HTTP PUT requests. Messages 310 might be informational only and not contain postback strings or computer program names. Messages 310 can be in a format different than described in these examples. Messages 310 can have content different that described in these examples. Messages 310 can be received using communication methodologies different than HTTP, one possible alternative would be to use COM to send messages 310 from the second computer program 270 to the first computer program 210 . In addition, the messages 310 received by the first computer program 210 are primarily intended for the first computer program 210 .
[0038] FIG. 4 a is an example of an array of messages 310 received by a first computer program 210 . Each row in the array corresponds to a received message 310 . Column 400 holds the headlines 300 of the received messages 310 . Column 410 holds either the postback string or the name of the computer program to launch. Column 420 holds the address of where to send the postback string or else a parameter to be used when launching a computer program. Column 430 holds the color to use when displaying the headline 300 .
[0039] FIG. 4 b is an example of a user interface 240 . 440 is a sequence of headlines 300 . In one embodiment, the sequence of headlines is displayed using a datagridview control in a window. Other ways of displaying the sequence of headlines are possible and fit within the scope of the invention.
[0040] FIG. 5 a is a flowchart of a method in the preferred embodiment. In step 500 , the first computer program 210 receives messages 310 on an event driven basis from at least two other computer programs. As indicated earlier the messages 310 can be received via HTTP, or a COM interface or any other way of exchanging messages between computer programs. If the messages 310 are received via HTTP, the message receiver 220 can comprise an HTTP listener.
[0041] In step 510 , a headline 300 is derived from the received message 310 . This step is usually performed in the message receiver 220 , but it can be performed in another functional block of the first computer program 210 . Deriving a headline 300 comprises obtaining summary text that corresponds to the received message 310 . Examples of deriving a headline 300 can include parsing an email message for the subject line or extracting a portion of text from an instant message. Another example of deriving a headline 300 can comprise selecting a certain field in a received message. Many other examples of deriving a headline 300 are possible.
[0042] In step 520 , the derived headline 300 is integrated into a sequence of headlines 440 . This step is usually performed in the headline integrator 230 , but it can be performed in another functional block of the first computer program. The array in FIG. 4 a can be a result of the headline integration in this step. In one embodiment, step 520 gets executed by a function call from the message receiver 220 . Also, in one embodiment the message receiver 220 is running on a different thread than the headline integrator 230 .
[0043] In step 530 , the sequence of headlines 440 is displayed as part of a user interface 240 . FIG. 6 shows an example of displaying the sequence of headlines 440 on a display 600 associated with the computing device 200 . Note that when the sequence of headlines 440 is displayed, headlines 300 corresponding to more recently received messages 310 are displayed below headlines 300 corresponding to less recently received messages 310 in the plane of the display 600 . This order can be reversed, such that when the sequence of headlines 440 is displayed, headlines 300 corresponding to more recently received messages 310 are displayed above headlines 300 corresponding to less recently received messages 310 , in the plane of the display 600 .
[0044] After a new message 310 is received by the first computer program 210 , the displayed sequence of headlines 440 is adjusted to show the most recent headlines 300 . Also, the most recent headline 300 can be displayed in reverse video for ten seconds. The displayed sequence of headlines 440 is substantially static except when a new message 310 is received or when user input directed at the displayed sequence of headlines 440 is detected. Further, the displayed sequence of headlines 440 can be made to become substantially transparent after ten seconds of no user input or no new messages 310 . When the user “mouseovers” the nearly transparent shadow of the displayed sequence of headlines 440 , the displayed sequence of headlines becomes fully visible once again. Similarly, when a new message 310 is received, the displayed sequence of headlines 440 is made fully visible.
[0045] FIG. 5 b is a flowchart of another method in the preferred embodiment. In step 540 , the displayed sequence of headlines 440 is monitored for user input. Single click, double click, finger tap, stylus tap, double tap or any other similar action is a user input. When a user input is detected in step 540 , then step 550 is executed. In step 550 it is determined which particular headline 300 in the displayed sequence of headlines 440 the user has directed input at. Further, a message can be sent from the first computer program 210 to the second computer program 270 in response to the user action. This is illustrated by example in FIG. 7 . In FIG. 7 , the user has clicked on a headline 300 derived from a message 310 sent by the second computer program 270 . In this example, the second computer program 270 is a location program. After the second computer program 270 receives the postback message, it can initiate its own actions. In this example, the the second computer program 270 displays the window 700 .
[0046] Additionally, in step 550 , instead of sending a postback message, a computer program can be launched, such as a word processor or internet browser.
[0047] Step 550 can comprise the additional step of displaying an interim user interface element that requires another indication from a user before a postback message is sent to the second computer program 270 or another computer program is launched.
[0048] This detailed description of the invention is illustrative only, many other ways of implementing the invention are possible. As discussed earlier, instead of using HTTP to send messages to the first computer program 210 , messages 310 could be sent using COM or by any of many other ways to communicate between running computer programs. The user interface could be implemented using textboxes instead of a datagrid control. Many other modifications are possible without departing from the invention.
[0049] While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention. | Methods and systems for receiving notifications from plural running computer programs and facilitating user interaction with the plural running computer programs are disclosed. | 6 |
[0001] This application claims benefit, under U.S.C. §119(a) of French National Applications Number 03.09641, filed Aug. 5, 2003, and 04.00906, filed Jan. 30, 2004; and also claims benefit, under U.S.C. §119(c) of U.S. provisional application 60/523,480, filed Nov. 19, 2003 This application is a divisional application of, and claims benefit to U.S. Ser. No. 10/909,503, filed Aug. 2, 2004.
FIELD OF THE INVENTION
[0002] The present invention relates to flexible semiaromatic polyamides with a low moisture uptake. These polyamides also have good elongation properties. These polyamides have a high thermomechanical strength. Polyamide-6 and polyamide-6,6 have high melting points but their conversion is difficult and, furthermore, their water uptake is too high, which is damaging to their mechanical properties and to their resistance to ageing. Furthermore, they are too rigid to be used as pipes; it is then necessary to render them flexible with plasticizers or impact modifiers. All the properties are then lost. Polyamide-12 and polyamide-11 are much used in the automobile industry because of their noteworthy mechanical properties, their ease of use and their resistance to ageing. However, their thermomechanical strength is inadequate beyond a working temperature of 160° C. The invention relates to polyamides which are to replace polyamide-12 and polyamide-11 but which have an improved thermomechanical strength while retaining their ease of conversion and their flexibility.
BACKGROUND OF THE INVENTION
[0003] There exist terephthalic copolyamides based on a 6 unit (for example, 6,6/6,T or 6/6,T or also 6,I/6,T, comprising predominantly 6,T) which have very high melting points, above 300° C. These products are very rigid and their elongation at break is less than 10%, which prevents them from being used in the field of extrusion of pipes. Patent EP 550 314 gives examples of copolyamides-12/6,T. U.S. Pat. No. 3,843,611 discloses copolyamides-12,12/12,T. U.S. Pat. No. 5,708,125 discloses copolyamides-10,6/10,T. None of these prior arts discloses a possible aptitude with regard to ageing. Furthermore, none of these prior arts discloses the need for flexible polyamides. The aim of the present invention is to find polyamides which have resistance to ageing when they are subjected to a high working temperature, while remaining flexible. Such compositions have now been found.
SUMMARY OF THE INVENTION
[0004] The present invention relates to a composition comprising, by weight, the total being 100:
[0005] 60 to 99.5% (preferably 70 to 93%) of at least one copolyamide of formula X/Y,Ar in which:
Y denotes the residues of an aliphatic diamine having from 8 to 20 carbon atoms, Ar denotes the residues of an aromatic dicarboxylic acid, X denotes either the residues of aminoundecanoic acid NH 2 —(CH 2 ) 10 —COOH, of lactam-12 or of the corresponding amino acid, or X denotes the unit Y,x, residue from the condensation of the diamine with an aliphatic diacid (x) having between 8 and 20 carbon atoms, or X denotes the unit Y,I, residue from the condensation of the diamine with isophthalic acid,
[0009] 0.5 to 40% (preferably 7 to 30%) of at least one product chosen from plasticizers, nanofillers, polyolefins, crosslinked polyolefins and additives.
[0010] The intrinsic viscosity of the copolyamide is advantageously between 0.5 and 2 and preferably between 0.8 and 1.8.
[0011] The advantage of these compositions is the low water uptake, which does not exceed 3% by weight.
[0012] Preferably, X/Y, Ar denotes:
11/10,T, which results from the condensation of aminoundecanoic acid, 1,10-decanediamine and terephthalic acid, 12/12,T, which results from the condensation of lactam-12, 1,12-dodecanediamine and terephthalic acid, 10,10/10,T, which results from the condensation of sebacic acid, 1,10-decanediamine and terephthalic acid, 10,I/10,T, which results from the condensation of isophthalic acid, 1,10-decanediamine and terephthalic acid.
[0017] The present invention also relates to structures comprising a layer composed of the above composition. This structure is of use in preparing devices for the storage or transfer of fluids, in particular in automobiles. The invention also relates to these devices. These devices can be tanks, pipes or containers. These structures can comprise other layers composed of other materials.
[0018] The compositions of the invention can replace rubbers or metals.
[0019] The compositions of the invention are also of use as materials for electrical cables and can replace fluoropolymers.
[0020] The compositions of the invention are of use as materials for formulations comprising fillers: e.g. magnetic fillers. The compositions of the invention then act as binder for fillers of this type.
DETAILED DESCRIPTION OF THE INVENTION
[0021] As regards the aromatic diacid, mention may be made of terephthalic acid, isophthalic acid, bibenzoic acid, naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, bis(p-carboxyphenyl)methane, ethylenebis(p-benzoic acid), 1,4-tetramethylenebis(p-oxybenzoic acid), ethylenebis(para-oxybenzoic acid) or 1,3-trimethylenebis(p-oxybenzoic acid). Preferably, this is terephthalic acid; it is denoted by “T”.
[0022] As regards “Y”, the diamine can be an α,ω-diamine comprising a straight chain. It preferably has from 9 to 14 carbon atoms. According to a preferred form, this is 1,10-decanediamine. It can be branched or can be a mixture of a linear (straight-chain) diamine and of a branched diamine.
[0023] As regards “X”, and more particularly “x” in “Y,x”, this is advantageously an aliphatic α,ω-diacid comprising a straight chain. It preferably has between 9 and 14 carbon atoms.
[0024] As regards the proportions of X, Y and Ar, Y and Ar are in stoichiometric proportions or proportions very close to stoichiometric.
[0025] There is advantageously between 0.5 and 0.7 mol of X per 1 mol of Y (or one mole of Ar).
[0026] 0.5 mol of X also means 0.5 mol of Y,x, that is to say 0.5 mol of Y and 0.5 mol of x in the Y,x group. Likewise, 0.5 mol of X also means 0.5 mol of Y,I, that is to say 0.5 mol of Y and 0.5 mol of I in the Y,I group.
[0027] If Y comprises a long chain, for example has at least of the order of 15 to 18 carbon atoms, then the proportions of X can be very low, indeed even zero. The copolyamide is reduced to Y,Ar. The invention also relates to the preceding compositions in which X/Y,Ar has become Y,Ar and Y denotes the residues of an aliphatic diamine having from 10 to 20 (preferably from 15 to 20 and better still from 18 to 20) carbon atoms.
[0028] If X/Y,Ar denotes 10,10/10,T, then the proportions of X can be higher and can be between 0.5 mol per 1 mol of Y and 1 mol per 0.05 mol of Y.
[0029] As regards the plasticizer, it is chosen from benzenesulphonamide derivatives, such as n-butylbenzenesulphonamide (BBSA), ethyltoluenesulphonamide or N-cyclohexyltoluenesulphonamide; esters of hydroxybenzoic acids, such as 2-ethylhexyl para-hydroxybenzoate and 2-decylhexyl para-hydroxybenzoate; tetrahydrofurfuryl alcohol esters or ethers, such as oligoethoxylated tetrahydrofurfuryl alcohol; esters of citric acid or of hydroxymalonic acid, such as oligoethoxylated malonate. Mention may also be made of decylhexyl para-hydroxybenzoate and ethylhexyl para-hydroxybenzoate. A particularly preferred plasticizer is n-butylbenzenesulphonamide (BBSA).
[0030] As regards the nanofillers, this term is used to denote particles of any shape, at least one of their dimensions being of the order of a nanometre. Advantageously, these are lamellar exfoliable fillers. In particular, the lamellar exfoliable fillers are silicates and in particular organophilic treated clays; these clays, which exist in the form of sheets, are rendered organophilic by insertion between the latter of organic or polymeric molecules and are obtained in particular according to a process as disclosed in U.S. Pat. No. 5,578,672.
[0031] Preferably, the clays used are of the smectite type, either of natural origin, such as, in particular, montmorillonites, bentonites, saponites, hectorites, fluorohectorites, beidellites, stibensites, nontronites, stipulgites, attapulgites, illites, vermiculites, halloysites, stevensites, zeolites, fuller's earths and mica, or of synthetic origin, such as permutites.
[0032] Mention may be made, by way of example, of the organophilic clays disclosed in U.S. Pat. No. 6,117,932. Preferably, the clay is modified with an organic substance via an ionic bond with an onium ion having 6 carbon atoms or more. If the number of carbon atoms is less than 6, the organic onium ion is too hydrophilic and thus the compatibility with the polymer (the blend of (A) and (B)) may decrease. Mention may be made, as examples of organic onium ion, of hexylammonium ions, octylammonium ions, 2-ethylhexylammonium ions, dodecylammonium ions, laurylammonium ions, octadecylammonium (stearylammonium) ions, dioctyldimethylammonium ions, trioctylammonium ions, distearyldimethylammonium ions, stearyltrimethylammonium ions and ammonium laurate ions. It is recommended to use a clay having the greatest possible contact surface with the polymer. The greater the contact surface, the greater the separation of the clay flakes. The cation exchange capacity of the clay is preferably between 50 and 200 milliequivalents per 100 g. If the capacity is less than 50, the exchange of the onium ions is inadequate and the separation of the clay flakes may be difficult. On the other hand, if the capacity is greater than 200, the bonding strength of the clay flakes to one another is so strong that the separation of the flakes may be difficult. Mention may be made, as examples of clay, of smectite, montmorillonite, saponite, hectorite, beidellite, stibensite, nontronite, vermiculite, halloysite and mica. These clays can be of natural or synthetic origin. The proportion of organic onium ion is advantageously between 0.3 and 3 equivalents of the ion exchange capacity of the clay. If the proportion is less than 0.3, the separation of the clay flakes may be difficult. If the proportion is greater than 3, decomposition of the polymer may occur. The proportion of organic onium ion is preferably between 0.5 and 2 equivalents of the ion exchange capacity of the clays. The nanofillers can be added to the monomers and can be present during the polymerization of the copolyamide or can be added after the polymerization.
[0033] As regards the crosslinked polyolefins, this phase can originate (i) from the reaction of two polyolefins having groups which react with one another, (ii) from maleicized polyolefins with a monomeric, oligomeric or polymeric diamino molecule, (iii) or from one (or more) unsaturated polyolefin carrying unsaturation and which can be crosslinked, for example, by the peroxide route. As regards the reaction of two polyolefins, this crosslinked phase originates, for example, from the reaction:
of a product (A) comprising an unsaturated epoxide, of a product (B) comprising an unsaturated carboxylic acid anhydride, optionally of a product (C) comprising an unsaturated carboxylic acid or of an α,ω-aminocarboxylic acid.
[0037] As regards the crosslinked polyolefins, mention may be made, as example of product (A), of those comprising ethylene and an unsaturated epoxide.
[0038] According to a first form of the invention, (A) is either a copolymer of ethylene and of an unsaturated epoxide or a polyolefin grafted by an unsaturated epoxide.
[0039] As regards the polyolefin grafted by an unsaturated epoxide, the term “polyolefin” is understood to mean polymers comprising olefin units, such as, for example, ethylene, propylene, 1-butene or all other α-olefin units. Mention may be made, by way of example, of
polyethylenes, such as LDPE, HDPE, LLDPE or VLDPE, polypropylene, ethylene/propylene copolymers, EPRs (ethylene/propylene rubber) or metallocene PEs (copolymers obtained by single-site catalysis), styrene/ethylene-butene/styrene (SEBS) block copolymers, styrene/butadiene/styrene (SBS) block copolymers, styrene/isoprene/styrene (SIS) block copolymers, styrene/ethylene-propylene/styrene block copolymers or ethylene/propylene/diene monomer (EPDM) terpolymers; copolymers of ethylene with at least one product chosen from salts or esters of unsaturated carboxylic acids or vinyl esters of saturated carboxylic acids.
[0043] Advantageously, the polyolefin is chosen from LLDPE, VLDPE, polypropylene, ethylene/vinyl acetate copolymers or ethylene/alkyl (meth)acrylate copolymers. The density can advantageously be between 0.86 and 0.965 and the melt flow index (MFI) can be between 0.3 and 40 (in g/10 min at 190° C. under 2.16 kg).
[0044] As regards the copolymers of ethylene and of an unsaturated epoxide, mention may be made, for example, of copolymers of ethylene, of an alkyl (meth)acrylate and of an unsaturated epoxide or copolymers of ethylene, of a saturated carboxylic acid vinyl ester and of an unsaturated epoxide. The amount of epoxide can be up to 15% by weight of the copolymer and the amount of ethylene at least 50% by weight.
[0045] Advantageously, (A) is a copolymer of ethylene, of an alkyl (meth)acrylate and of an unsaturated epoxide.
[0046] Preferably, the alkyl (meth)acrylate is such that the alkyl has 2 to 10 carbon atoms.
[0047] The MFI (melt flow index) of (A) can, for example, be between 0.1 and 50 (g/10 min at 190° C. under 2.16 kg).
[0048] Examples of alkyl acrylate or methacrylate which can be used are in particular methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate or 2-ethylhexyl acrylate. Examples of unsaturated epoxides which can be used are in particular:
aliphatic glycidyl esters and ethers, such as allyl glycidyl ether, vinyl glycidyl ether, glycidyl maleate, glycidyl itaconate, glycidyl acrylate and glycidyl methacrylate, and alicyclic glycidyl esters and ethers, such as 2-cyclohexen-1-yl glycidyl ether, diglycidyl cyclohexene-4,5-dicarboxylate, glycidyl cyclohexene-4-carboxylate, glycidyl 5-norbornene-2-methyl-2-carboxylate and diglycidyl endo-cis-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate.
[0051] According to another form of the invention, the product (A) is a product having two epoxide functional groups, such as, for example, bisphenol A diglycidyl ether (BADGE).
[0052] Mention may be made, as examples of product (B), of those comprising ethylene and an unsaturated carboxylic acid anhydride.
[0053] (B) is either a copolymer of ethylene and of an unsaturated carboxylic acid anhydride or a polyolefin grafted by an unsaturated carboxylic acid anhydride.
[0054] The polyolefin can be chosen from the polyolefins mentioned above which has to be grafted by an unsaturated epoxide.
[0055] Examples of unsaturated dicarboxylic acid anhydrides which can be used as constituents of (B) are in particular maleic anhydride, itaconic anhydride, citraconic anhydride and tetrahydrophthalic anhydride.
[0056] Mention may be made, as examples, of copolymers of ethylene, of an alkyl (meth)acrylate and of an unsaturated carboxylic acid anhydride and copolymers of ethylene, of a saturated carboxylic acid vinyl ester and of an unsaturated carboxylic acid anhydride.
[0057] The amount of unsaturated carboxylic acid anhydride can be up to 15% by weight of the copolymer and the amount of ethylene at least 50% by weight.
[0058] Advantageously, (B) is a copolymer of ethylene, of an alkyl (meth)acrylate and of an unsaturated carboxylic acid anhydride. Preferably, the alkyl (meth)acrylate is such that the alkyl has 2 to 10 carbon atoms.
[0059] The alkyl (meth)acrylate can be chosen from those mentioned above.
[0060] The MFI of (B) can, for example, be between 0.1 and 50 (g/10 min at 190° C. under 2.16 kg).
[0061] According to another form of the invention, (B) can be chosen from aliphatic, alicyclic or aromatic polycarboxylic acids or their partial or complete anhydrides.
[0062] Mention may be made, as examples of aliphatic acids, of succinic acid, glutaric acid, pimelic acid, azelaic acid, sebacic acid, adipic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, dodecenesuccinic acid and butanetetracarboxylic acid.
[0063] Mention may be made, as examples of alicyclic acids, of cyclopentanedicarboxylic acid, cyclopentanetricarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanedicarboxylic acid, cyclohexanetricarboxylic acid, methylcyclopentane-dicarboxylic acid, tetrahydrophthalic acid, endo-methylenetetrahydrophthalic acid and methyl-endo-methylenetetrahydrophthalic acid.
[0064] Mention may be made, as examples of aromatic acids, of phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid or pyromellitic acid.
[0065] Mention may be made, as examples of anhydrides, of the partial or complete anhydrides of the above acids.
[0066] Use is advantageously made of adipic acid.
[0067] It would not be departing from the scope of the invention if a portion of the copolymer (B) is replaced by an ethylene-acrylic acid copolymer or an ethylene-maleic anhydride copolymer, the maleic anhydride having been completely or partially hydrolysed. These copolymers can also comprise an alkyl (meth)acrylate. This portion can represent up to 30% of (B).
[0068] With regard to the product (C) comprising an unsaturated carboxylic acid, mention may be made, as examples, of the products (B) completely or partly hydrolysed. (C) is, for example, a copolymer of ethylene and of an unsaturated carboxylic acid and advantageously a copolymer of ethylene and of (meth)acrylic acid.
[0069] Mention may also be made of the copolymers of ethylene, of an alkyl (meth)acrylate and of acrylic acid.
[0070] These copolymers have an MFI of between 0.1 and 50 (g/10 min at 190° C. under 2.16 kg).
[0071] The amount of acid can be up to 10% by weight and preferably 0.5 to 5%. The amount of (meth)acrylate is from 5 to 40% by weight.
[0072] (C) can also be chosen from α,ω-aminocarboxylic acids, such as, for example, NH 2 —(CH 2 ) 5 COOH, NH 2 —(CH 2 ) 10 COOH and NH 2 (CH 2 ) 11 —COOH and preferably aminoundecanoic acid.
[0073] The proportion of (A) and (B) necessary to form the crosslinked phase is determined according to the usual rules of the art by the number of reactive functional groups present in (A) and in (B).
[0074] For example, in the crosslinked phases comprising (C) chosen from α,ω-aminocarboxylic acids, if (A) is a copolymer of ethylene, of an alkyl (meth)acrylate and of an unsaturated epoxide and (B) a copolymer of ethylene, of an alkyl (meth)acrylate and of an unsaturated carboxylic acid anhydride, the proportions are such that the ratio of the anhydride functional groups to the epoxy functional groups is in the region of 1.
[0075] The amount of α,ω-aminocarboxylic acid is then from 0.1 to 3% and preferably 0.5 to 1.5% of (A) and (B).
[0076] As regards (C) comprising an unsaturated carboxylic acid, that is to say (C) being chosen, for example, from ethylene/alkyl (meth)acrylate/acrylic acid copolymers, the amount of (C) and (B) can be chosen so that the number of acid functional groups and of anhydride functional groups is at least equal to the number of epoxide functional groups and, advantageously, products (B) and (C) are used such that (C) represents 20 to 80% by weight of (B) and preferably 20 to 50%.
[0077] It would not be departing from the scope of the invention if a catalyst were added.
[0078] These catalysts are generally used for the reactions between the epoxy groups and the anhydride groups.
[0079] Mention may in particular be made, among the compounds capable of accelerating the reaction between the epoxy functional group present in (A) and the anhydride or acid functional group present in (B), of:
tertiary amines, such as dimethyllaurylamine, dimethylstearylamine, N-butylmorpholine, N,N-dimethylcyclohexylamine, benzyldimethylamine, pyridine, 4-(dimethylamino)pyridine, 1-methylimidazole, tetramethylethylhydrazine, N,N-dimethylpiperazine, N,N,N′,N′-tetramethyl-1,6-hexanediamine or a mixture of tertiary amines having from 16 to 18 carbons and known under the name of dimethyltallowamine 1,4-diazabicyclo[2.2.2]octane (DABCO) tertiary phosphines, such as triphenylphosphine zinc alkyldithiocarbamates.
[0084] The amount of these catalysts is advantageously from 0.1 to 3% and preferably 0.5 to 1% of (A)+(B)+(C).
[0085] As regards the noncrosslinked polyolefins, mention may be made of the polyolefins described in the preceding section and intended to be grafted by reactive groups. Mention may also be made of the products (A) or (B) or (C) of the preceding section but used alone in order not to crosslink. Mention may be made, by way of examples, of the EPR or EPDM elastomers, it being possible for these elastomers to be grafted in order to make it easier to render them compatible with the copolyamide. Mention may also be made of acrylic elastomers, for example those of the NBR, HNBR or X-NBR type.
[0086] As regards the preparation of the compositions of the invention, use may be made of any conventional process for the synthesis of polyamides and copolyamides.
[0087] The compositions according to the invention can additionally include at least one additive chosen from:
dyes; pigments; brighteners; antioxidants; flame retardants; UV stabilizers; nucleating agents. | The present invention relates to a flexible semiaromatic polyamide composition with a low moisture uptake, made up by weight, the total being 100:
A) 60 to 99.5% (preferably 70 to 93%) of at least one copolyamide of formula X/Y,Ar in which there are between 0.5 and 0.7 mol of X per 1 mol of Y, and in which
Y denotes the residues of 1,10-decanediamine, Ar denotes the residues of terephthalic acid, X denotes the residue of aminoundecanoic acid NH 2 —(CH 2 ) 10 —COOH, the unit Y,I residue from the condensation of the diamine (Y) with isophthalic acid, wherein said composition is a flexible semiaromatic copolyamide;
B) 0.5 to 40% (preferably 7 to 30%) of at least one product chosen from plasticizers, nanofillers, polyolefins, crosslinked polyolefins and additives. | 2 |
BACKGROUND AND BRIEF DESCRIPTION OF INVENTION
The present invention relates to an improved apparatus for roll finishing bevel gears, and more particularly, the invention provides for an adjusting means which offers extreme rigidity and precision for adjusting the root angle formed on a workpiece.
It is known in the art to roll finish bevel gear workpieces by applying a relatively high force between a die and a workpiece which are brought into meshing engagement. By feeding the die and the workpiece relative to each other it is possible to displace up to several thousandths of an inch of material on previously formed tooth profiles of the workpiece, and this serves to finish the tooth profiles to a final dimension and surface condition. Machines for carrying out this type of basic operation were disclosed as early as 1928 in Gleason et al U.S. Pat. No. 1,669,818 and have been disclosed in more recent years in U.S. Pat. Nos. 3,604,235 and 3,605,467, for example. As noted in the just-mentioned patent disclosures, apparatus for roll forming may typically include a first spindle means for carrying a gear member and a second spindle means for carrying a pinion member for meshing with the gear member during the rolling operation. Either the gear member or the pinion member may be a die for imparting final tooth profiles on a workpiece, and the other of the gear member or the pinion member comprises the workpiece itself.
Roll forming equipment requires relatively strong and rigid machine components because of the very high force loads required to displace material on a cold workpiece by the forceful engagement of a die with the workpiece. Thus, recent designs for such equipment have tended to contain and support the separate spindles of the machine so as to establish a rigid and fixed angular relationship between the pinion member and the gear member. Typically, this relationship has provided for a right angular disposition of the axes of rotation of the two members, and one axis may be offset from the other when a hypoid pinion or gear is being finished. In addition to fixed angular relationships, the early U.S. Pat. No. 1,669,818 provided for an adjustment of one spindle axis relative to the other for purposes of adjusting the root angle (also referred to as pressure angle) relationship between a meshing pinion and gear. However, the type of adjustment shown in U.S. No. 1,669,818 was not applied to a machine of the type contemplated herein in which both the die axis and the workpiece axis are movable about pivot points for effecting (a) initial engagement and final disengagement of the die and the workpiece and (b) relative feeding of the die and the workpiece during the rolling operation to obtain full depth of roll. In contrast, the root angle adjustment means of the present invention can be used with apparatus having such pivotal feed motions for its separate spindle axes, and makes provision for such pivotal feed motions without loss of a root angle setting. In addition, the root angle adjusting means of the present invention is positioned in close proximity to the working end of a spindle, and this establishes a fixed and precise stop limit which is not lost through bending moments of the spindle.
In accordance with a preferred embodiment of the present invention, a machine frame is designed to support the loads of a first spindle means carrying a gear member and a second spindle means carrying a pinion member so that the pinion and gear members can be brought into meshing engagement with one another for roll forming tooth profiles on whichever one of the members comprises a workpiece. The first spindle means is mounted for movement about a pivot axis which intersects the axis of rotation of the second spindle means to thereby provide for a pivotal feeding motion of the gear member relative to the pinion member. The second spindle means is likewise mounted for pivotal movement about an axis, and its movement functions to engage and disengage the pinion and gear at the beginning and end of each rolling operation for loading and unloading purposes. In the illustrated embodiment, the root angle adjusting means is operatively associated with the second spindle means, and thus, the adjusting means of this invention is designed and constructed to accommodate the pivotal motions of the second spindle means in its movements for engaging and disengaging a meshing pinion and gear.
In accordance with a specific embodiment of the invention the adjusting means includes a movable wedge-shaped member carried by the machine frame for establishing a stop surface against which a movable portion of the second spindle means (or its associated mounting means) can be moved when the second spindle means is pivoted to bring a pinion member into meshing engagement with a gear member. The adjusting means is positioned in close proximity to the working end of one of the movable spindles of the machines so that a precisely defined position for the stop surface can be maintained during a rolling operation. In addition, the invention provides for means for displacing the adjusting means completely out of its operative position to thereby remove the stop surface to provide clearance for gross movements of the second spindle means about its pivot axis. The displacing means is arranged to move the wedge-shaped member transversely from its adjusted position so that it can be returned to its operative position without loss of precision in whatever root angle setting has been set up for a particular job. Thus, gross movements of the second spindle means, as required for loading and unloading the apparatus, can be accomplished without disrupting a precision setting of the root angle relationship between a pinion and a gear.
These and other features and advantages of the root angle adjusting means of the present invention will become apparent in the more detailed discussion which follows, and in that discussion reference will be made to the accompanying drawings as briefly described below:
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a side elevational view, partly in cross section, of the apparatus of the present invention; FIG. 2 is a front elevational view, partly in cross section, of the apparatus shown in FIG. 1 as seen on line 2--2 of FIG. 1;
FIG. 3 is a depiction of a gear, showing the root angle for the gear;
FIG. 4 is an enlarged view of a root angle adjusting means included in the overall view of FIG. 1; and
FIG. 5 is a view of the root angle adjusting means of FIG. 4, as seen in the same scale as FIG. 4 on line 5--5.
DETAILED DESCRIPTION OF INVENTION
FIGS. 1 and 2 depict a type of roll forming apparatus contemplated by the present invention. Such apparatus includes a machine frame having a base portion 10, a top portion 12, and side portions 14, all of which are secured together to form a rigid assembly for supporting other components of the apparatus. A first mounting means 16 functions to carry a first spindle means 18, and the first spindle means 18 includes a known form of chucking device for securing a gear member 20 in driving relationship therewith so that a motor means 22 can drive the gear member 20 about an axis 23. The first mounting means is suspended within the machine frame so as to be movable about a pivot axis at 24 which intersects an axis of rotation 26 associated with a pinion member 28. Known means are provided for journaling support structures of the first mounting means 16 in operative relationship to the machine frame so that the load of the first mounting means 16 is suspended for such pivotal movement within the machine frame. Hydraulic ram devices 30 are interconnected between a portion of the mounting means 16 and side portions 14 of the machine frame for applying controlled pivotal movements to the first mounting means 16 and its supported gear member 20. These movements, about the pivot axis at 24, function to feed the gear member 20 relative to the pinion member 28 during rolling engagement to thereby obtain full depth of roll during a finishing operation.
A second mounting means 32 serves to mount a second spindle means 34 for limited pivotal movement about a pivot axis at 36, and a motor means 37 is connected to the spindle means 34 for driving a supported pinion member 28 about axis 26. Suitable control devices can be provided for correlating the driving actions of the separate motor means 22 and 37. The pivot axis at 36 is parallel to the pivot axis 24 for the first mounting means. A hydraulic ram means 38 is interconnected between a portion of the second mounting means 32 and the machine frame for moving the second mounting means 32 about its pivot axis 36. These movements can be considered relatively gross movements which involve a complete disengagement or re-engagement of a pinion member 28 and a gear member 20 for purposes of unloading and loading the machine between its operating cycles. The second mounting means 32 is supported within a generally cylindrical support structure 40 having a bearing surface 42 for being received within a mating bearing surface formed in portions of the machine frame, to thereby provide for pivotal movement of the second mounting means and its contained second spindle means 34.
As illustrated, the first spindle means 18 is positioned within the machine frame in a generally vertical attitude, and the second spindle means 34 is positioned at substantially a right angle thereto in a generally horizontal attitude. The separate axes of rotation of the two spindle means may be offset (non-intersecting) relative to one another for rolling operations for hypoid pinions or gears. In other applications, the two axes of rotation can be disposed at right angles to one another in an intersecting relationship.
The various features which have been discussed so far in this detailed description of the invention are separately known in the art of roll forming of gears, although it is not known whether the particular combination of dual pivotal motions for separate spindles has been utilized in a single machine application. It is known, however, to provide for a pivotal feeding motion of a die and a workpiece which are in rolling engagement with each other (see, for example, U.S. Pat. No. 3,695,078).
The present invention is concerned with an improved adjusting means for adjusting the root angle of a workpiece which is to be roll finished, and the adjusting means is of a particular design for use in combination with a pivotally movable spindle for bringing a die and a workpiece into and out of meshing engagement. As shown in FIG. 3, the root angle of a gear comprises an angle x between an element of a root cone 44 and an axis of rotation 46 of the gear. This same definition applies to pinion members. In either case, it is desirable to provide for a fine adjustment of root angle between a die and a workpiece in order to control displacement of material on the tooth surfaces being finished. Machines which do not provide for this type of precision adjustment are limited in what they can do in precision gear finishing applications because no root angle adjustment in tooth bearing pattern can be made between a given die and a workpiece. If the bearing pattern is not exactly right, a new die is required for such machines. As indicated in the preliminary discussion portion of this specification, it is known from U.S. Pat. No. 1,669,818 to provide for a root angle adjustment in gear rolling equipment, but the type of adjustment means shown in that patent is different from the one disclosed herein for use in combination with a pivoting spindle means and does not establish a rigid stop surface at the working end of a spindle.
FIG. 1 generally indicates a root angle adjusting means 50 as being carried in a portion of the machine frame which also contains the second mounting means 32. As shown in greater detail in FIGS. 4 and 5, the adjusting means 50 includes a movable wedge-shaped member 52 carried by the machine frame for establishing a stop surface 54 against which a portion of the second spindle means 34 (or its associated mounting means 32) can be moved when the second spindle means 34 is pivoted to bring the pinion member 28 into meshing engagement with the gear member 20 for a starting rolling operation. It can be seen that the stop surface 54 is established in close proximity to the working end (where work is being performed) of the spindle means 34, and this assures an unchanging relationship between the stop surface and the spindle during a rolling operation. The wedge-shaped member 52 is secured to a portion of the machine frame with fastening bolts 56. The bolts 56 pass through slots 58 formed through the wedge-shaped member 52, and the slots 58 permit a range of movement for the wedge-shaped member along it longitudinal axis. This movement can be effected by any known adjusting means, including manually operated screws or cams which apply a force to one end or the other of the wedge-shaped member 52. In the illustrated embodiment, cam elements 60 are provided at opposite ends of the wedge-shaped member, and these cam elements are arranged to be manually turned in such a way that one cam element can apply a force to an associated rod member 62 (for contacting one end of the wedge-shaped member) while the opposing cam element allows a retraction of its associated rod member 62 at the opposite end of the wedge-shaped member. Longitudinal movement of the wedge-shaped member 52 lowers or raises the position of the stop surface 54 through a follower plate assembly 64. The follower plate assembly is loosely mounted to a portion of the machine frame with bolts 66 passing through elongated slots 68 so as to permit free up and down movement of the follower plate. The follower plate 64 functions to accommodate very slight misalignments between the second spindle means (and its associated mounting means 32) and the wedge-shaped member 52.
Referring back to the general relationship shown in FIG. 1, it can be seen that pivotal movement of the second spindle means 34 is limited in the counterclockwise direction by the establishment of the stop surface 54 with the adjusting means 50. Thus, by moving the mounting means 32 and its contained spindle means 34 to a preset limit position against the stop surface 54, a preferred angular relatioinship is established between the spindle axes 23 and 26. This relationship defines the finished root angle which will be formed on a workpiece by a rolling engagement of the pinion member 28 with the gear member 20. After full depth of roll has been obtained (through the pivotal feeding motion of the first mounting means 16, as discussed above), it is necessary to move the pinion and die members out of engagement with each other so that a finished workpiece can be removed and a new workpiece loaded into the apparatus. The unloading sequence involves a first step of withdrawing the gear member 20 from its full depth engagement with the pinion member 28 (by actuating the hydraulic ram devices 30 to pivot the first spindle means and its associated mounting means in a counterclockwise direction about axis 24), followed by a second step of removing the pinion member 28 from any engagement at all with the gear member 20 (by actuating the ram device 38 to move the second spindle means and its associated mounting means in a counterclockwise direction about axis 36). It can be seen from the FIG. 1 relationships that the second step of unloading cannot be effected until the stop surface 54 is released or removed from its operative position for limiting movement of the second spindle means. Thus, it is necessary to provide, with the type of apparatus discussed herein, a separate means for displacing the wedge-shaped member 52 out of its operative position to thereby release the stop surface 54 from its adjusted position and to provide clearance for gross movements of the second spindle means in the counterclockwise direction.
A preferred displacing means includes a shifting rod 70 for displacing the wedge-shaped member 52 to the dotted line position shown in FIG. 4. The shifting rod 70 is secured to the wedge-shaped member so as to advance and retract the wedge-shaped member with corresponding movements of the shifting rod, and movement of the shifting rod 70 is effected through known hydraulic controls which admit and release hydraulic fluid to and from a chamber 72 containing a piston element 74 attached to the shifting rod 70. It can be seen from the FIG. 4 illustrating that the follower plate assembly 64 is not displaced with such movements of the wedge-shaped member 52. This serves to eliminate any interference between the follower plate assembly and the wedge-shaped member during gross movements of the second spindle means, and the follower plate assembly 64 can simply follow such gross movements by virtue of its loosely mounted relationship to the machine frame and the provision of elongated slots 68 which are of a sufficient dimension to permit movement of the second spindle means 32 to a position which completely disengages the pinion and gear members 28 and 20.
After an unloading and loading operation has been completed, the second spindle means 34 is returned to a position which brings the pinion and gear members into partial meshing engagement (but not full depth engagement as determined by the feeding motion of the first spindle means), and the wedge-shaped member 52 is returned to its operative position to define a pre-set limit of travel for the second spindle means. Then the second spindle means is moved slightly into a limit position against the stop surface 54, and a new rolling operation can begin.
Having defined a specific embodiment of the root angle adjusting means of this invention, it can be appreciated that this type of adjusting means provides for a precision setting of a root angular relationship between a die and a workpiece and this precision relationship is not lost when the adjusting means is displaced from its operative position for loading and unloading the apparatus. In addition, it can be appreciated that the adjusting means can be associated with either spindle of a machine provided it is positioned near the working end of the spindle to prevent loss of setting due to bending of the spindle. | An improved apparatus for roll forming tooth profiles on workpieces is provided with an adjusting means for adjusting the root angle of a workpiece. The adjusting means is designed to withstand the large forces generated with equipment of this type and can be used in combination with a separate means for pivotally moving a die and a workpiece relative to one another for bringing the die and the workpiece into and out of meshing engagement. | 8 |
This invention was made with Government support under Grant No. CBT-8809422 awarded by the National Science Foundation. The Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
The present invention relates to extraction processes and more particularly to the use of liquid water at elevated temperatures and pressures as a solvent for the liquid-liquid extraction of a stream containing fatty acids and/or resin acids.
The fact that fatty acids can become completely soluble in liquid water at elevated temperatures has been known for at least 40 years (see Bailey's Industrial Oil and Fat Products, Volume 1, 4th Ed.).
Crude tall oil is a major by-product of the Kraft pulping process for making paper. The primary components are fatty acids, resin acids, and neutrals. In the prior art, resin acids are often referred to as rosin acids, and neutrals are typically indicated as unsaponifiables or non-saponifiables as they lack an acid group and therefore are not subject to saponification. The most valuable of the neutrals found in tall oil are the sterols, high molecular weight alcohols of biological importance.
The most widely used prior art method for recovering the acid components of tall oil is vacuum distillation. However, the major disadvantage of such process is that the sterols cannot be directly recovered. Most of the sterols present react with fatty and resin acids by esterification to form a heavy, low value residue known as pitch. Such reaction also decreases the quantity of fatty and resin acids recovered. Further, the unreacted sterols end up as impurities in the recovered resin acid streams. Northern and hardwood trees, which are now being used with greater frequency by the paper pulping industry, have a relatively high sterols content such that pitch formation and acid contamination is even greater when these raw woods are processed.
Thus, it is generally known in the prior art that sterols and other neutrals are best recovered by removal before distillation. Christenson et al U.S. Pat. No. 2,530,809 discloses a process for the fractionation of tall oil prior to distillation. Generally, tall oil, if not already present as such, is converted to a tall oil soap with fatty and resin acids present as soaps; neutrals (unsaponifiables), including sterols, are unchanged. The tall oil soap is mixed with a lower alcohol and subjected to an extraction with an organic phase which is immiscible with the soap solution but which acts as a solvent for the unsaponifiable neutrals. The neutral-free soaps are then converted to free fatty acids and free resin acids and are separated by conventional vacuum distillation. The neutrals are washed and stripped to eliminate the solvent.
Other patents which have employed this general scheme for the separation of tall oil into its various constituents include Hasselstrom et al U.S. Pat. No. 2,547,208, which discloses a method for refining tall oil soap employing ketones as a solvent for the undesirable neutrals; Chase et al U.S. Pat. No. 2,866,781, which discloses a method of separating non-acids from soap stocks in which an aqueous solution of soap is subjected to extraction with an ester solvent for the removal of unsaponifiable material; and Metchel et al U.S. Pat. No. 3,803,114, which discloses a process for purifying tall oil to produce unsaponifiable-free tall oil products wherein the unsaponifiables are extracted into a hydrocarbon phase. In Holmbom et al U.S. Pat. No. 3,965,085, a method for refining soaps using solvent extraction is disclosed in which the soap solution is first mixed with a low molecular weight ketone before the addition of a water-immiscible solvent such as hexane. The extracted soap phase is then distilled for removal of the ketone.
Cleary U.S. Pat. No. 4,495,094 discloses a process for separating fatty and resin acids from unsaponifiables in which the tall oil is not converted to a soap but is merely contacted with a solvent comprising an alcohol and water solution at room temperature which is selective for and extracts the fatty and/or resin acids. Kulkarni et al U.S. Pat. No 4,496,478 discloses a process for extracting unsaponifiables from fatty and rosin acids wherein an emulsion is formed with an organic solvent and an emulsifying liquid. A formation of three phases is effected by the application of centrifugal force. The three phases, an organic solvent phase containing the fatty acids, an emulsifying liquid phase, and a semi-solid sludge phase, are then separated.
Various patents are directed to the recovery of sterols and acids from the pitch produced during the distillation of tall oil. Generally, this pitch is treated by methods similar to those discussed above. It is converted to a soap and extracted with a solvent to remove the unsaponifiable matter. Christenson et al U.S. Pat. No. 2,530,810 discloses such a process wherein the soaps are dissolved in an alcohol prior to extraction by a hydrocarbon. The neutrals are then washed and stripped of the hydrocarbon solvent. Julian U.S. Pat. No. 3,840,570 discloses a process for preparing sterols from tall oil pitch wherein the pitch is dissolved in a solvent mixture of alcohol and hydrocarbon. Water, at temperatures ranging from 32° F. to 212° F., is then added to extract the acid soaps. The hydrocarbon phase, which contains the sterol esters, is saponified and the free sterols are recovered. In Lihtinen U.S. Pat. No. 3,926,936, the pitch is saponified at a temperature of 200°-300° C. The reaction product soaps are then acidified to produce an oil. The oil is distilled, and the distillate may be further refined by previously known fraction distillation processes. By such method, the sterols are dehydrated to form hydrocarbons, and the fatty and resin acids are recovered. Force U.S. Pat. No. 3,943,117 discloses a method for saponifying pitch in the presence of an amine catalyst to produce fatty and resin acid soaps. Harada et al U.S. Pat. No. 3,887,537 discloses a process for recovering fatty acids and rosin acids following pitch saponification by thin film evaporation.
Amer U.S. Pat. No 4,422,966 discloses a process for separating neutral compounds from tall oil soaps wherein the soap is contacted with a supercritical fluid solvent for the tall oil neutral compounds such that neutrals are extracted into the solvent. Preferably, the solvents employed by the Amer process are hydrocarbon gases which are exposed to supercritical conditions of temperature and pressure. Gases disclosed as suitable for the process include methane, ethane, propane, butane, ethylene, propylene and the like. One problem encountered in recent supercritical fluid extraction systems such as that of Amer has been the very low solubilities which many compounds of low volatility, particularly those which contain polar substituent groups, exhibit in supercritical gases. These low solubilities mean that the solvent recycle rates in a supercritical extraction process are very high such that the economics are less attractive.
Hughes U.S. Pat. No. 4,524,024 discloses a process of enhancing the recovery of fatty acids from tall oil pitch. Added to the generally known vacuum distillation process is an additional hydrolysis step. During this intermediate step, a pitch fraction is fed into a hydrolyzer at a pressure of from 40 kg/cm 2 to 70 kg/cm 2 where it is subjected to water having a temperature of from 260° C. to 280° C. During the hydrolysis step, free fatty acids are derived by hydrolytic splitting of the esterified fatty acids present in the pitch fraction. The entire hydrolysis reaction product is fed into the distillation process where the newly freed fatty acids are recovered.
Upon recovery of the neutrals by any of the prior art processes discussed above or by the process of the present invention, purification may be desired. U.S. Pat. Nos. 2,499,430 and 4,422,974 disclose methods for the recovery of sterols of high purity from neutrals.
Another problem to which the present invention is applicable is the purification of the deodorized distillate or sludge formed as a by-product during the deodorization of oils such as soybean oil, linseed oil, cottonseed oil, safflower oil, rice bran oil, corn oil and sunflower oil. Such distillate, like the tall oil discussed above, generally contains fatty acids and neutrals. The more valuable neutral components of the distillates are sterols and tocopherols (Vitamin E). Various methods for removing the fatty acids from the deodorizer distillate have been addressed by the prior art. For example, Takagi et al U.S. Pat. No. 4,454,329 discloses a process wherein the free fatty acids within the distillate are subjected to esterification by the addition of an alcohol. Sampathkumar U.S. Pat. No. 4,594,437 discloses a process whereby the free fatty acids are isolated by the formation of a urea complex.
SUMMARY OF THE INVENTION
The present invention recognizes and addresses the foregoing disadvantages, and others, of prior art recovery and separation techniques. Thus, it is an object of the present invention to provide a method for recovering the sterols from tall oil.
Yet another object of the present invention is to recover the acids from crude tall oil.
Yet another object of the present invention is to provide a method for recovering the sterols from an acid stream that does not require chemical solvents or produce toxic wastes or other environmentally undesirable side effects.
A further object of the present invention is to provide a method for recovering the sterols from tall oil which does not require conversion of the tall oil to a tall oil soap.
Still another object of the present invention is to provide a method for extracting fatty and resin acids from a sterol-containing acid stream that is capable of reducing the amount of sterols in the purified acid stream to less than one percent by weight.
A further object of the present invention is to provide a method for recovering the sterols from an acid stream that is more convenient and less expensive than existing methods.
A further object of the present invention is to provide a method for recovering the acids and sterols from an acid stream such that the formation of pitch in a subsequent acid distillation is significantly reduced.
Still another object of the present invention is to provide a method for removing the fatty acids from a deodorized distillate such that a tocopherol-rich stream is recovered.
Yet another object of the present invention is to provide a method for recovering a tocopherol-rich stream from deodorized distillate that dispenses with the need for organic solvents and chemical reactions.
A further object of the present invention is to provide a method for separating and/or recovering a sterol-rich stream, a fatty acid stream and a resin acid stream from tall oil.
Still a further object of the present invention is to provide a method for recovering a tocopherol-rich stream from the distillate product of the deodorization of vegetable oils derived from soybeans, corn, cottonseed, linseed, sunflower seed, etc.
Yet another object of the present invention is to provide a method for separating a stream containing both fatty acids and resin acids into two streams, one having an increased concentration of fatty acids relative to the primary stream and one having an increased concentration of resin acids relative to the primary stream.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
The present invention employs water at elevated temperatures and pressures as a solvent for separation, by liquid-liquid extraction, of the components of naturally occurring oils and resins. Examples of compositions suitable for separation by the present method include crude tall oil and the distillate by-product of the deodorization of vegetable oils, although other biochemical and synthetic chemical compositions can be separated into their relative components by this invention.
Generally, the objects of the present invention are achieved by providing a method of solvent extraction for separating the components of a primary stream containing fatty and/or resin acids which requires contacting the stream with liquid water at temperatures ranging from 250° C. to 360° C. As a result of this contact, two liquid phases are formed. Thus, an extract phase is formed containing water and those components which are more soluble in water, e.g., the acids. Concurrently, a raffinate phase is formed containing those components which are less soluble in water, e.g., the sterols.
The present method, as applied to tall oil and vegetable oil distillate, requires that the temperature be in the range described above. At lower temperatures, the solubility of the acids in water is so low as to render the process impractical. At higher temperatures, the primary stream of interest and water generally will only form one liquid phase and the method cannot be used. An additional difficulty at elevated temperatures is that significant thermal degradation of the primary stream components will generally occur.
As is generally known in the prior art of liquid-liquid extraction, the operating temperature is generally selected so as to obtain values of k D and β which are as high as possible. For example, for a primary stream consisting of fatty acids and sterols, the distribution coefficient k D is defined as ##EQU1## and the selectivity β is defined as ##EQU2##
As is generally known by those skilled in the art, maximum values of both k D and β do not occur at the same temperature. Therefore, the operating temperature which those skilled in the art will use will depend on the economic value of the primary stream of interest and on the desired purity of the products. An additional consideration for the present method is that the presence of undesirable thermal degradation of the components of interest may also affect the choice of operating temperature.
The present invention provides a method for removing and/or recovering valuable neutrals such as sterols and tocopherols from fatty acid-containing streams such as tall oil and deodorized distillate. A sterol and/or tocopherol-rich stream is produced by extracting off a greater portion of acids along with a lesser portion of neutrals.
Streams which are particularly appropriate for treatment by the present process include crude tall oil and deodorized distillate, the latter being a by-product of deodorization of vegetable oils. Tall oil contains primarily fatty acids, resin acids and neutrals, the most valuable of the neutrals being sterols. The present process is employed to separate the fatty acids and the resin acids, at least partially, from the sterols thereby producing a fatty and resin acid stream and a sterol-enriched stream, and then, if desired, to separate the resin acids from the fatty acids such that three separate streams of product are generated. Deodorized distillates are composed of fatty acids, neutrals and other components. The most valuable neutrals of the distillate are tocopherols; however, sterols are also present. Thus, the process of the present invention is used to separate the fatty acids from the tocopherols, sterols and other components of the distillate. It should be noted that the present process is generally appropriate for the separation of acids (saponifiables) from neutrals (unsaponifiables) in any relevant composition and does not require saponification. More generally, the present process is applicable to the liquid-liquid extraction of those organic molecules having polar substituent groups thereon and which are essentially insoluble in water at ambient temperatures, but which, because of the polar substituent group, become highly soluble in liquid water at elevated temperatures.
Preferably, the present invention is practiced as a continuous, countercurrent liquid-liquid extraction system. The appropriate operating temperatures for extracting a complex chemical mixture such as a natural oil is highly dependent on the composition of the mixture. For example, in the case of tall oil, the operating temperature should be high enough such that acid solubilities are significant in the aqueous phase, but not so high that the tall oil stream to be extracted is completely soluble in water. For example, the solubility of a Southern pine tall oil in liquid water is only 0.1% by wt. at 250° C.; however, it increases to 3.0% by wt. at 300° C. and to 6.0% by wt. at 312° C. At temperatures above approximately 340° C., this tall oil stream is completely soluble in liquid water.
Thus, for such mixture, the preferred operating temperature which yields both good solubilities (k D 's) and selectivities (β's) is approximately 300° C. to 330° C. For other tall oil mixtures which contain fewer neutrals than the present mixture, complete solubility in liquid water will occur at lower temperatures and the preferred operating temperature range will necessarily be lower. On the other hand, tall oil derived from Northern and hardwood trees contains more neutrals than the present tall oil, and does not become completely soluble in liquid water until higher temperatures, estimated as 360° C. Thus, higher operating temperatures are feasible.
Similar effects occur depending on the composition of the acids in tall oil. For example, a tall oil richer either in lower molecular weight fatty acids (such as palmitic) or in resin acids is more soluble in water than Southern pine tall oil, and preferable operating temperatures are lower.
Generally, the preferred operating temperature range is that range in which optimum k D 's and β's are obtained for the mixture of interest. For the many different types of crude tall oil and deodorized distillate, as well as other acid-containing streams, such operating temperatures will range from 250° C. to 360° C.
A complicating factor in the selection of the appropriate operating temperature for a given stream is that undesirable side reactions, such as the decarboxylation of resin acids, the dehydration of sterols, and esterification become significant enough to have a detrimental effect on product quality as operating temperatures approach 350° C. Thus, it may be preferable to operate at lower temperatures to improve product purity at the expense of reduced solubilities in water. Although the formation of pitch by esterification, the reaction of alcoholic neutrals with the carboxylic acids present, is seen at excessively high temperatures, one advantage of the present invention is that pitch formation is deterred at lower temperatures. The water present in the liquid phases inhibits the formation of esters.
The process of the present invention may also be employed to separate resin acids from fatty acids as noted above. This separation is possible because the resin acids are generally more soluble than tall oil fatty acids in liquid water at elevated temperatures. Depending on the types of fatty and resin acids present, good k D 's and β's occur generally within the temperature range of 250° C. to 340° C., and the resin acids are effectively separated and removed from the fatty acids.
Thus, the process of the present invention provides a method for separating the various components of fatty acid and/or resin acid containing compositions.
Other objects, features, and aspects of the present invention are discussed in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
A full and enabling disclosure of the present invention, including the best mode thereof, to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:
FIG. 1 is a schematic diagram of a solvent extraction system in accordance with the present invention;
FIG. 2 is a schematic diagram of a countercurrent liquid-liquid solvent extraction system in accordance with the present invention; and
FIG. 3 is a plotted graph representing the solubility of tall oil in the extract and raffinate phases as a function of temperature.
FIG. 4 is a plotted graph representing the multi-stage, countercurrent liquid-liquid solvent extraction of the acids and sterols in tall oil.
FIG. 5 is a plotted graph representing the multi-stage, countercurrent liquid-liquid solvent extraction of the fatty and resin acids of tall oil.
Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the present preferred embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield still a further embodiment. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
A preferred embodiment of the method of the present invention is schematically shown in FIG. 1. The solvent extraction system is generally designated 10 and includes generally a means for contacting the two liquids such as equilibrium coil 12 and a means for separating two phases such as viewing cell 14. A solution having neutrals and acids, such as, for example, tall oil, is forced through line 16 by pump 18. Water flowing through line 20, forced therethrough by pump 22, is mixed with the tall oil at point 24. The mixture flows therefrom through line 26 into equilibrium coil 12 wherein the two solutions are more thoroughly mixed and are heated to operating temperature. The liquid mixture subsequently enters view cell 14 where two phases are allowed to separate. The bottom extract phase, represented generally at 28, is substantially aqueous, containing water and extracted acids. The top raffinate phase 30 is substantially organic, or at least "more organic" in character than the extract phase, as it contains, primarily, neutrals, fatty and resin acids, and water. The two phases exit the view cell, aqueous phase 28 exiting by line 32, and organic phase 30 exiting by line 34. After each phase cools to around 200° C., the respective components are no longer soluble in the liquid water such that water separates from each phase and leaves the organic components. These organics may be further purified. Examples given below illustrate the partial separation achieved by fatty acid and resin acid extraction with the apparatus of FIG. 1.
It is to be understood that such apparatus, generally employed in laboratory experimentation rather than full-scale production, represents one equilibrium stage for liquid-liquid mass transfer. An equilibrium stage may be thought of as one unit for liquid-liquid contact and inter-phase transfer. The liquid-liquid extraction column of FIG. 2 provides a plurality of equilibrium stages such that greater mass transfer of acids from the tall oil into the aqueous extract phase will occur over the length of the column. Other devices which provide for a plurality of equilibrium stages, such as, for example, mixer-settlers, are also within the scope of the present invention.
Generally, the present process is carried out at operating temperatures ranging from about 250° C. to about 360° C. Accordingly, the pressure must always be maintained above the bubble point pressure of all process streams at any given operating temperature. However, because the vapor pressure of all components, other than water, is very low, in practice the pressure must be maintained above the vapor pressure of water. Although extraction of acids into the aqueous phase appreciably begins around 250° C., solubilities of the fatty acids which occur in tall oil and soybean oil deodorized distillate which are high enough to be practical are generally not achieved until about 280° C. Optimum operating conditions for a Southern pine tall oil are between 280° C. and 330° C.; for a Northern or hardwood tall oil, between 280° C. and 350° C. In this temperature range, both solubilities, or k D 's, and selectivities, or β's, are relatively high, and undesirable side reactions are minimal.
As has been discussed before, an absolute upper limit on the operating temperature occurs when the tall oil and water become completely miscible, since two liquid phases must exist for an extraction to be carried out. Depending on the composition of the tall oil, this will occur at temperatures from 320° C. to greater than 360° C. For example, referring to FIG. 3, for the Southern pine tall oil tested, two liquid phases exist up to at least 315° C. It is estimated that only one liquid phase will exist above approximately 340° C.
At temperatures above about 330° C., undesirable side reactions begin to have a detrimental effect on product quality. Above about 350° C., these side reactions become a prohibitive factor, thereby limiting operating temperature range.
One such side reaction which is a common problem in the prior art is the formation of pitch. Pitch is, generally, unwanted esters produced by the reaction of alcoholic neutrals present in the system with carboxylic (fatty and resin) acids. Although pitch is formed by the present process at excessively high temperatures, pitch formation is low up to about 330° C., presumably because the water present in both phases inhibits the formation of esters. Other undesirable side reactions which occur at excessive temperatures include the decarboxylation of resin acids and the dehydration of sterols. These reactions are limited by maintaining an operating temperature below about 350° C. and are minimized by maintaining an operating temperature below about 330° C. Thus, optimum extraction of fatty and resin acids from a Southern pine tall oil is achieved between about 280° C. and about 330° C.; for a Northern or hardwood tall oil between 280° C. and 350° C.
Further, it is within the scope of the present invention to either bring the tall oil into contact with water at room temperature and then heat the two or to heat the water and/or the tall oil prior to mixing such that the mixture is at the appropriate temperature. However, in order to prevent the reaction of tall oil, any heating of the oil in the absence of water should be limited in time and degree. Generally, the apparatus of FIG. 1 allows for the former method of heating while the apparatus of FIG. 2 requires, at least in part, the latter. However, regardless of the heating method employed, the pressure must be maintained above the vapor pressure of water at every temperature attained in order to maintain the water in its liquid state.
Similarly, the process of the present invention may be used to separate the components of the distillate obtained during the deodorization of various vegetable oils. The fatty acids present in such distillate may be extracted at temperatures ranging from about 250° C. to about 350° C., although optimum extraction is achieved at temperatures at which the fatty acids become more soluble in water, i.e., above 280° C. The upper limit of operating temperature is determined by the temperature at which the side reactions of tocopherols become unacceptable. The resultant organic phase, after cooling to separate out the water, is rich in sterols and valuable tocopherols (Vitamin E) which may be purified by methods known in the prior art.
As noted above, the aqueous extract phase produced from a tall oil extraction may be cooled to separate the extracted fatty acids and resin acids from the water in which they were dissolved. Generally, such acids are essentially insoluble in water at 200° C. so that separation, as by decanting, may be readily achieved at 200° C. or below. The water-free, substantially pure fatty acid and resin acid stream achieved upon such cooling may be further separated into a substantially resin acid-free fatty acid stream and a substantially fatty acid-free resin acid stream by the process of the present invention. It is necessary to effect an operating temperature between about 250° C. and 340° C. in order to achieve both good solubilities (k D 's) and selectivities (β's) for separating the resin acids and fatty acids. Streams richer in resin acids (and thus more soluble in water) could be operated at lower temperatures than those richer in fatty acids, and vice versa.
Depending on the composition of the mixture, there will be a relatively narrow temperature range in which the fatty acids will be relatively insoluble and the resin acids relatively soluble in liquid water such that good k D 's and β's will be obtained. For example, for a mixture of fatty and resin acids such as would be found in Southern pine tall oil, the operating temperature range would be expected to be between 280° C. and 330° C. This relative difference in solubilities is employed to achieve a separation of resin acids from fatty acids by the process of the present invention. Thus, referring to the apparatus of FIG. 1, a stream containing fatty and resin acids, such as the water-free acid product of the aqueous extract phase produced above, is forced by pump 18 through line 16 to mixing point 24 where it is mixed with the water fed in by line 20. The acid-water mixture is then pumped into equilibrium coil 12 where the water and acid streams are thoroughly mixed and heated to operating temperature. Optimum separation for a fatty and resin acid mixture derived from tall oil is achieved at operating temperatures in the range of about 280° C. through about 330° C. The liquid mixture then passes to view cell 14 where a bottom extract phase 28 and a top raffinate phase 30 are allowed to separate. Because of the lower operating temperatures of this run, the bottom extract phase 28 will contain water, a higher concentration of resin acids, and fatty acids. The top raffinate phase 30 will contain fatty acids, a lesser concentration of resin acids, and water. The two phases are pulled off by lines 32 and 34, respectively, and are allowed to cool. Upon cooling, the acids in each phase, no longer soluble in the now cooled water, may be separated therefrom such as by decanting.
An alternative apparatus for achieving the process of the present invention on a larger, more practical and efficient scale is illustrated schematically in FIG. 2. A conventional countercurrent liquid-liquid extraction column designated generally 100 is illustrated with feed lines 116 and 120 entering same at the bottom and top, respectively, thereof. Means are provided within the column for providing tortuous flow or mechanical agitation in order to achieve sufficient surface to contact the two liquids. Further, means are provided for maintaining the temperature within the column at an appropriate operating temperature depending on the composition of the feed stream and the desired separation. As above, the pressure within the column must be held above the vapor pressure of water at the given operating temperature in order to maintain the water in its liquid state. Thus, looking to FIG. 2, the feed stream containing components for separation enters the column through line 116. Water at elevated temperatures enters the column through line 120. Within the column the two streams are contacted and heated to operating temperature. Two outlet streams in the form of two separate phases are produced. A substantially aqueous extract phase exits the lower end of the column through line 132. The substantially organic raffinate phase exits the upper end of the column through line 134.
Upon exiting the column, the two phases are cooled to below about 200° C. for removal of the water. The composition of each phase will depend on the composition of the initial feed stream and the operating temperature of the run. For example, if a tall oil is fed into the column and the operating temperature is maintained between about 280° C. and about 350° C., the aqueous extract phase will comprise primarily fatty acids, resin acids and water. Upon cooling below about 200° C., the water will separate out, and a substantially pure stream of fatty acids and resin acids will be provided. This separation is illustrated generally by phase separator 150 where, upon cooling below about 200° C., water is pulled off by line 152 and the stream of fatty acids and resin acids exit through line 154. Similarly, the composition of the organic raffinate phase will depend on the composition of the feed stream and the operating temperature. Again, for a tall oil feed stream and temperatures ranging from about 280° C. to about 350° C., the organic phase will comprise primarily sterols and other neutrals, fatty acids and resin acids, and water. Upon cooling in phase separator 160, water will separate out and exit by line 162 while the remaining organic components exit line 164. A qualitative illustration of the column extraction process is shown on a ternary extraction diagram in FIG. 4. Note that the raffinate phase R is rich in neutrals and the extract phase E is rich in water and acids.
The apparatus of FIG. 2 is readily adaptable to a continuous system wherein a feed stream such as tall oil may be continually pumped into the liquid-liquid extraction column, and the organic phase may be routed to another process for further purification of the sterols and other neutrals by one of the existing methods described earlier. Similarly, the stream containing relatively pure fatty acids and resin acids carried by line 154 may be routed to another such column for feeding therein as a feed stream and for fatty and resin acid separation by extraction. Again, such separation is carried out at lower operating temperatures ranging from about 280° C. to about 330° C. For such acid separation system, the aqueous extract phase will comprise water and resin acids, while the organic raffinate phase will comprise primarily fatty acids and resin acids not separated out by the run through the column, as well as water. A qualitative illustration of this process is shown on a ternary extraction diagram in FIG. 5. Here the extract phase E is rich in water and resin acids. The raffinate phase R is rich in fatty acids.
Accordingly, it is seen that the countercurrent liquid-liquid extraction column of FIG. 2 lends itself to continuous processes; further, such column may be provided in series with other columns, thereby allowing for further separation of the organic components of both the aqueous and organic phases.
FIG. 2 shows a standard countercurrent liquid-liquid extraction column. However, different operating modes from that shown are also within the scope of the present invention. For example, extract reflux could be used to increase the purity of the extract phase leaving the column. Another possible operating mode would be to operate various stages of the column at different operating temperatures. For example, the column could be operated at a higher temperature at the bottom (to improve acid solubility) and at a lower temperature at the top (to reduce sterol dehydration and esterification).
EXAMPLE 1
Prior to separation in the extraction apparatus of FIG. 1, a Southern pine tall oil sample was washed with hexane to remove lignin and solid matter. The tall oil entered the system by line 16 at a flow rate of 100 mL/h. Water was pumped in through line 20 at a flow rate of 400 mL/h.
The two liquids were mixed and introduced into equilibrium coil 12 for heating and further mixing. The coil was made from three sections of stainless steel tubing with the two end sections, having lengths of approximately 15 m, outer diameters of 1.59 mm and inner diameters of 0.762 mm, connected by a three-meter length of tubing having an outer diameter of 3.18 mm and an inner diameter of 1.59 mm to enhance mixing. If desired, a Kenics-type static mixer of approximately 3/16" o.d. can be used to further enhance mixing. An in-line Type E thermocouple was used to monitor the temperature of the mixture exiting the equilibrium coil.
A nitrogen temperature bath provided heating. The nitrogen bath employed was a forced-convection type bath and was sealed from outside air and surrounded by insulation. Pyrex windows on opposite sides of the bath allowed for observation into the view cell. Heating was achieved by circulating the nitrogen across three Chromalox strip heaters regulated by a Leeds and Northrup controller. Input to the controller was from a 100 ohm platinum resistance thermometer. Thermal gradients within the nitrogen bath were estimated to be ±1 Kelvin.
After exiting the equilibrium coil, the equilibrated, two-phase mixture entered viewing cell 14 for phase separation. The viewing cell employed was a Model 11-T-20 liquid level gauge (Jerguson Gage and Valve Co.) which was modified for high temperature and high pressure operation. The original cell body was replaced with one made from Carpenter 450 stainless steel. The new fluid chamber was machined to the original height and depth but the width was reduced from 1.6 cm to 0.95 cm. The cell windows were made of high-temperature aluminosilicate glass (Corning Glass Works) mounted on graphite gaskets. Mica shields were used to protect the cell windows from the etching effects of water at elevated temperatures. Belleville washers of 17-7 PH stainless steel (Associated Springs, Inc.) were used on the cover plate bolts to compensate for thermal expansion effects and to maintain sealing at elevated temperatures. The internal volume of the cell was approximately 30 mL.
The two phases separated by gravity with the heavier, substantially aqueous extract phase exiting the bottom of the cell by line 32 and the lighter, substantially organic raffinate phase exiting the top of the cell by line 34. The two phases were analyzed for each separate run with FIG. 3 illustrating the mass fraction of tall oil in the respective phases at each temperature. A water-free content for each phase was then calculated.
For three runs, an initial portion of tall oil was divided into three samples. As determined by gas chromatography, each sample had a β-sitosterol content of 5.6% by weight. The present experiment was performed on each of the samples at three separate temperatures: 301° C., 306° C. and 312° C. After exiting the viewing cell, each phase was analyzed for tall oil content. As shown in FIG. 3, analyses indicate that the bottom extract phase contains from about 3% to 6% by weight tall oil with the remainder being water. The unextracted tall oil remains in the top raffinate phase, which also contains substantial amounts of water at the elevated temperatures of operation (see FIG. 3). As discussed above, this water inhibits undesirable side reactions.
After cooling, the tall oil of each phase was analyzed for β-sitosterol and total neutrals content. Table I below shows the results of this analysis for each of the three runs. The percent by weight of β-sitosterol and neutrals is given for each phase on a water-free basis. Other analyses (not shown) also indicated that pitch formation was less than one percent by weight in all cases.
TABLE I______________________________________ wt % β-sitosterol (neutrals) inTemp (°C.) Feed Extract Raffinate______________________________________301 5.6 (11.3) 0.7 (3.8) 5.5 (13.5)306 5.6 (11.3) 0.7 (5.5) 9.3 (13.7)312 5.6 (11.3) 1.6 (4.7) 10.5 (17.0)______________________________________
The acid numbers of the tall oil feed stream and the two product streams are illustrated in Table II below. Generally, the acid number for a given sample may be interpreted as milligrams of potassium hydroxide required to neutralize one gram of sample to a pH of 10.5 Thus, higher acid numbers indicate higher acid concentrations. The acid numbers below were determined by ASTM D803-65.
TABLE II______________________________________ Acid Number inTemp (°C.) Feed Extract Raffinate______________________________________301 158.3 176.2 157.9306 158.3 174.5 155.7312 158.3 173.4 151.6______________________________________
EXAMPLE 2
A model tall oil was synthesized from β-sitosterol and oleic acid. The oleic acid used was 92% by weight pure with linoleic and stearic acid impurities. The β-sitosterol was 90% by weight pure with 10% by weight campesterol. Four samples were prepared with varying β-sitosterol contents as shown in Table III below. The experiment of Example 1 was performed on each of the four samples at 299° C., except that the flow rate of the model tall oil was 175 mL/h and of the water was 200 mL/h. The resulting concentrations of β-sitosterol for each of the product phases on a water-free basis is shown in Table III. The percent by weight of water in each phase is shown in Table IV.
TABLE III______________________________________ wt % β-sitosterol inRUN # Feed Extract Raffinate______________________________________1 6.5 0.5 4.82 6.5 0.5 5.23 7.6 0.5 5.94 13.0 1.0 11.0______________________________________
TABLE IV______________________________________ wt % water inRUN # Extract Raffinate______________________________________1 97.5 27.22 97.5 27.43 97.5 26.44 97.7 25.0______________________________________
EXAMPLE 3
A neutrals-free model tall oil was synthesized from oleic acid and dehydroabietic acid. The oleic acid was identical to the used in Example 2. The dehydroabietic acid was 85% pure by weight with impurities being other resin acids. The experiment of Example 2 was performed on two samples: one at 299° C. and one at 303° C. The compositions of the feed, extract, and raffinate phases on a water-free basis are shown below.
TABLE V______________________________________ wt. % dehydroabietic acid inTemp (°C.) Feed Extract Raffinate______________________________________298 16.6 28.9 15.2303 16.6 26.0 15.2______________________________________
The percent by weight of water in each phase is shown in Table VI.
TABLE VI______________________________________ wt % water inTemp (°C.) Extract Raffinate______________________________________298 97.5 28.4303 96.2 32.6______________________________________
EXAMPLE 4
The experiment of Example 1 was performed on two samples of a deodorized distillate of soybean oil. The flow rate of the distillate was 150 mL/h and of the water was 225 mL/h. One sample was extracted at 298° C.; the other at 307° C. A comparison of the fatty acid, tocopherol, and sterol levels in the feed, extract, and raffinate phases on a water-free basis is shown below in Tables VII and VIII. Analysis of the sterols, tocopherols and fatty acids was by gas chromatography. The percent by weight of water in each phase is shown in Table IX.
TABLE VII______________________________________ ##STR1##Temp (°C.) Feed Extract Raffinate______________________________________298 2.1 31.1 2.3307 2.1 18.9 2.2______________________________________
TABLE VIII______________________________________ ##STR2##Temp (°C.) Feed Extract Raffinate______________________________________298 2.5 27.8 2.6307 2.5 37.3 2.5______________________________________
TABLE IX______________________________________ wt % water inTemp (°C.) Extract Raffinate______________________________________298 97.8 14.8307 97.7 18.0______________________________________
These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to be limitative of the invention so further described in such appended claims. | A process for producing increased concentrations of valuable neutrals such as sterols and tocopherols from fatty and/or resin acid-containing streams, such as tall oil and vegetable oil distillate, employs liquid water at elevated temperatures and pressures. The neutrals are concentrated by extracting fatty acids as well as resin acids of high purity. Temperature-dependent solubility differences allow for the further separation of resin acids from fatty acids. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. National Phase of PCT/RU2012/000446, filed on Jun. 7, 2012, which is incorporated by reference herein in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to antennas, in particular, to patch antennas used in global navigation satellite systems (GNSS).
[0004] 2. Description of the Related Art
[0005] Patch antenna systems are used in different radio electronic devices. They are widely applicable in ground satellite navigation systems (GPS, GLONASS, Galileo etc.), with the help of which a position of an object can be quickly and accurately determined at any point of the world. One of the main reasons for reduced GNSS positioning accuracy of land objects is related to receiving not only the line-of-sight satellite signal but also signals reflected from surrounding objects, and especially from the Earth's surface. The strength of such signals depends directly on the antenna's directional diagram (DD) in the rear hemisphere.
[0006] A right-hand circularly polarized signal (RHCP) is used as a working signal in navigation systems. Signals reflected from the Earth's surface, when there are no major surface features, are mostly left-hand circularly polarized signals (LHCP). This also holds true for signals of satellites that are at an angle over the horizon that is higher than Brewster's angle, that is, for typical soils, about 10-15 degrees over the horizon plane. Considering this, a GNSS antenna systems need to have a lower DD level in the rear hemisphere, and primarily, a lower component of the LHCP (cross-polarized) signal. A reduction in antenna weight and dimensional characteristics is also required.
[0007] The simplest method of reducing DD level in the rear hemisphere is mounting the antenna directly on a metal or impedance ground plane. However, this results in increasing antenna dimensions. Another method is the use of an additional antenna, the field of which is anti-phase-added to the main antenna field. This provides a reduction in the radiation level of the rear hemisphere. U.S. Pat. No. 6,836,247 B2 shows a design of a circularly-polarized antenna in the form of two patch (MP) radiators axial-symmetrically disposed one under another (see FIG. 1 a ). A ground plane of the top radiator is under a radiating patch, and a ground plane of the bottom radiator is over the radiating patch. In an isolated cavity of the ground planes, there is a low-noise amplifier (LNA). The top radiator is actively excited by pins; the bottom radiator is passively excited. Such a design provides a noticeable reduction in LHCP field only in the vicinity of anti-normal direction, while the antenna's vertical dimension still remains very large.
[0008] Modern high-precision positioning receivers employ signals of different frequencies. Operating GPS frequencies are 1575 MHz (L1-band), 1227 MHz (L2-band) and a frequency of 1175 MHz (L5-band) was recently added. GLONASS and GALILEO satellite systems also broadcast some operating frequencies. In total, the operating frequencies of GNSS systems lie in two frequency ranges: low-frequency (LF 1165-1300 MHz) and high-frequency (HF 1525-1605 MHz). Antennas of high-precision navigation devices need to operate in the both frequency bands. In most cases, antenna designs include two radiators operating at their own frequencies. U.S. Pat. 6,836,247 B2 describes a dual-band stacked antenna ( FIG. 1 b ). Such a combined antenna includes two active MP radiators disposed one over the other, and two passive ones. The radiating patch of the low-frequency radiator serves as a ground plane of the high-frequency radiator. Bandwidth expansion of each radiator is normally attained by increasing the distance between the radiating patch and ground plane, i.e., increasing the thickness of MP radiator. Note that an increase in LF radiator thickness results in increasing the distance between active and passive HF radiators. This, in turn, causes reduction in their coupling and excitation level of the passive radiator, and, hence in the antenna's less efficient operation.
[0009] The proposed technical solution is intended at solving cross-polarized (LHCP) field suppression problems in a wide angle sector of the rear hemisphere, enhancing the operation of the passive HF radiator in the dual-band antenna, and reducing antenna dimensions.
SUMMARY OF THE INVENTION
[0010] An antenna system for receiving navigation satellite signals is proposed, comprising a patch radiator consisting of a radiating patch disposed over a ground plane which is excited by, for example, exciting electric pins or slots, from a connected power circuit of the MP radiator, and a horizontal loop radiator axially disposed around the MP radiator. The radiating patch and ground patch can have the same dimensions, or the radiating patch can be larger or smaller than the ground patch. A cavity can be made directly under the ground patch, where power circuits of the loop radiator and the MP radiator can be located.
[0011] The loop radiator is a conducting ring, for example, made of wire or conductive film; its vertical axis matches the symmetry axis of the MP radiator. In another embodiment, the loop radiator can be disposed at the same distance from the surface of the radiating and ground patches, or it can be shifted toward the ground plane. Inductive elements can be sequentially connected with the loop radiator.
[0012] The loop radiator is excited by transmission lines at least at one point, for example, by two-wire transmission lines connected to the power supply circuit of the loop radiator. The power supply lines provide excitation of right hand circularly-polarized waves in the direction of DD maximum. The antenna system also includes a dividing circuit, whose input is the input of the antenna, and the power supply circuits of MP and loop radiators are connected to the outputs. The power supply circuits provide anti-phase excitation of LHCP waves for the MP and loop radiators in the rear hemisphere. The proposed combination of MP and loop radiators compensates for LHCP field in a wide angle sector.
[0013] To reduce overall dimensions, the space between the radiating patch and the ground patch of the MP radiator can be filled with a dielectric, or a slowing structure can be installed, for example, made as a set of conductive periodic elements, or a set of capacitive impedance elements can be used, which are arranged along the perimeter of the ground patch and/or the radiating patch of the MP radiator. The elements of the slowing structure can be a set of separate ribs, or combs, or teeth, or pins. Capacitive elements are also a set of separate ribs, or combs, or teeth, or pins. As another embodiment, the dielectric filler can have grooves/slots where two-wire transmission lines are located to connect the power circuit to the loop radiator, or it can be made in the form of two dielectric segments between which power lines are located.
[0014] A compact dual-band antenna system is proposed to receive signals from two frequency bands, comprising an active high-frequency MP radiator, under which there is an active low-frequency radiator. Each of the active radiators includes a radiating patch disposed under the corresponding ground plane. MP radiators are excited, for example, by electric pins or slots powered by power circuits of the corresponding frequency band. The radiating patch of the active LF band serves as a ground plane of the active HF MP radiator, and in the vicinity of the active HF radiator, there is a loop HF radiator, which is in axial alignment with the active HF radiator. Under the ground patch of the active LF radiator, there is a passive LF radiator at a certain distance from the ground plane, which is an MP radiator as well. This MP radiator is excited by electromagnetic coupling with the active LF MP radiator.
[0015] Another embodiment has an active HF loop radiator which is excited by two-wire lines connected to the HF loop radiator power circuit at least at one point. To provide a uniform excitation field, four excitation points are preferably used. The power circuits excite two-wire lines with equal amplitudes, with a sequential phase shift of −90° ensuring excitation of RHCP waves in the front hemisphere. The antenna system also includes an HF dividing circuit, the input of which is the HF antenna input, and the power circuits of HF MP and loop radiators are connected to the outputs. The power circuits provide anti-phase excitation of LHCP waves for HF MP and loop radiators in the rear hemisphere. The LF active radiator input is the LF antenna input.
[0016] In another embodiment, the LF passive radiator can be a loop coaxially disposed at a certain distance from the bottom active LF radiator.
[0017] In another embodiment, the LF loop radiator can also be active and excited similarly to the active HF loop radiator described above.
[0018] The HF or LF loop radiator is a conductive ring to which inductive elements can be sequentially connected. The vertical symmetry axis of the LF or HF loop radiator coincides with the symmetry axis of the corresponding HF or LF MP radiators.
[0019] In another embodiment, HF or LF loop radiator can be arranged at an equal distance from the surface of the corresponding radiating and ground patches or be shifted toward the ground patch, for example, be in the same plane as the ground patch or lower than the ground patch.
[0020] A cavity where power circuits of loop radiators and MP radiator of the corresponding band are easily installed can be directly under the ground patch of the LF radiator.
[0021] In another embodiment, slot excitation can be used to excite MP radiators in the above-said structures.
[0022] Additional features and advantages of the invention will be set forth in the description that follows. Yet further features and advantages will be apparent to a person skilled in the art based on the description set forth herein or may be learned by practice of the invention.
[0023] The advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
[0024] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS
[0025] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
[0026] In the drawings:
[0027] FIG. 1 a shows a conventional antenna system.
[0028] FIG. 1 b shows a conventional dual-band antenna based on a stacked construction.
[0029] FIG. 2 shows a section view above the proposed antenna system comprising a MP radiator, and a loop radiator in the form of a wire ring.
[0030] FIG. 3 shows a proposed antenna with capacitive elements in the form of conductive petals/lobes.
[0031] FIG. 4 shows a proposed antenna system with inductive elements.
[0032] FIG. 5 shows a section view above of the proposed antenna system with a loop radiator shifted towards the ground patch of the MP radiator.
[0033] FIG. 6 shows a proposed antenna system with passive excitation, where the diameter of the radiating patch is larger than the ground patch diameter.
[0034] FIG. 7 shows a proposed dual-band antenna with a passive HF loop radiator and a passive LF MP radiator.
[0035] FIG. 8 shows a proposed dual-band antenna with an active loop radiator of HF band and a passive MP radiator of LF band.
[0036] FIG. 9 shows a proposed dual-band antenna with passive loop radiators of the LF and HF bands.
[0037] FIG. 10 illustrates DD calculation results for the proposed antenna system.
[0038] FIG. 11 illustrates DD calculation results for the case of a shifted loop radiator (i.e., shifted towards the ground plane).
DETAILED DESCRIPTION OF THE INVENTION
[0039] Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
[0040] This described apparatus suppresses LHCP field in a wide angle sector of the rear hemisphere and reduces overall antenna dimensions. This is achieved by an antenna design comprising a MP radiator and an additional radiator in the form of a conductive loop disposed around and coaxially with the main MP radiator. Suppression of radiation in the rear hemisphere is the result of field interference of two radiators. The dimensions of the antenna are smaller than that of the conventional design.
[0041] Below there are given variants of antenna design with active and passive excitation of the loop radiator.
[0042] FIG. 2 shows an antenna design with an actively-excited loop radiator. The design includes a MP radiator, which comprises radiating patch 201 disposed above flat metal ground plane 202 . Between them there is a layer filled with air or a dielectric. To excite the MP radiator, electric pins 205 are used, which are galvanically contacted with the radiating patch 201 . The pins are connected to the MP radiator powering circuit through holes in ground plane 202 . The power circuit is installed over ground plane 202 in screened cavity 206 .
[0043] In another embodiment, excitation of MP radiators can be implemented with the help of slots in metal ground plane 202 or radiating patch 201 . Another embodiment, the power supply circuit of MP radiator can be installed in a different location, e.g., on the radiating patch 201 .
[0044] Standard methods of exciting circularly-polarized waves are used, for example, using two electric pins. However, four-pin excitation scheme permits achieving more uniformity of field in the azimuth. In the design shown in FIG. 2 , four electric pins 205 are mounted symmetrically relative to the vertical symmetry axis of radiating patch 201 .
[0045] To reduce overall dimensions of the MP radiator, space between patch 201 and ground plane 202 can be partially or fully filled with a dielectric. In this case, actual dimensions of the radiator decrease by √{square root over ( )} times (where is the effective dielectric permeability, which is equal to dielectric permeability of the dielectric material if the space is fully filled with dielectric). In the design of FIG. 2 the dielectric filler is made in the form of two dielectric discs 203 and 204 with holes for exciting pins 205 and cavity 210 . Between these elements, there are two-wire lines 209 to power the loop radiator, and a reference dielectric patch 211 to fix it.
[0046] At least one loop radiator 207 is installed coaxially with the MP radiator. The loop radiator 207 is made of conductive material, for example, wire, thin plates or film with dielectric substrate. The dielectric substrate serves as structural basis 211 for the loop radiator. A few loop radiators arranged vertically, one over another at a certain distance, can be used. A dielectric hollow cylinder can serve as a basis for the radiators.
[0047] FIG. 2 shows a wire ring which is fixed on the dielectric patch 211 clipped between dielectric discs 203 and 204 . The length of the loop 207 is equal to about the wavelength of the antenna operating band. The loop radiator 207 has four excitation points 208 , which are powered by the power circuit in the cavity 210 via two-wire lines 209 . This cavity 210 can be in the middle of the radiator, as well as at any other place. Two-wire lines are preferable due to their symmetry, but different line types can be used as well, for example, coaxial or micro-strips. Power circuits 206 and 210 provide amplitude-phase relationship of power signals (equality of amplitudes and −90° phase shift), which are needed to excite RHCP waves. RHCP waves are excited in the front hemisphere.
[0048] The antenna design includes also a dividing circuit that powers the powering circuits 206 and 210 . The dividing circuit can be disposed, for example, in the cavity 206 together with the powering circuit of MP radiator. The antenna input is the input of the dividing circuit. The dividing circuit ensures such amplitude-phase relationship of the powering signals that LHCP waves of the loop and MP radiators would be anti-phase added in the rear hemisphere. The dividing circuit can be made by any known method, for example, using micro-strip lines. To decouple/isolate the MP and loop radiators, the latter is preferably located equidistantly from the patches 201 and 202 of the MP radiator.
[0049] Another embodiment that reduces MP radiator dimensions includes a slowing structure in the form of a periodic sequence of conductive elements shaped as ribs, combs or pins. This structure is installed in the space between radiating patch 201 and ground plane 202 , instead of a dielectric filler. The slowing structures are disposed on one of the patches 201 and 202 or on both patches, opposite with a half-period shift.
[0050] FIG. 3 shows an antenna design with smaller dimensions of MP radiator and without a slowing structure. In this case, capacitive impedance elements in the form of conductive strips or teeth 312 and 313 , connected to radiating patch 301 and ground plane 302 , respectively, are installed along the perimeter of radiating patch 301 and ground plane 302 . Strips 312 and 313 are arranged perpendicularly to the plane of patches 301 and 302 in pairs opposite to each other with a gap.
[0051] To reduce outer dimensions of the loop radiator shown in FIG. 4 , it can be made as conductor legs 407 , in whose gaps elements with inductive impedance 414 are included.
[0052] FIG. 5 shows a design with passive excitation. A loop radiator does not have its electric excitation circuit, and it is excited by the field of the MP radiator. Efficient excitation of loop radiator 507 , is provided if it is located in the vicinity of the plane of ground patch 502 , for example, at the same level or slightly below.
[0053] FIG. 6 shows that the dimensions of radiating patch 601 can be larger than dimensions of ground plane 602 , i.e., the radiating patch becomes a ground plane and vice versa. Such an arrangement guarantees more efficient excitation of the loop radiator for a passively-excited system.
[0054] FIG. 7 shows a proposed dual-band stacked antenna design. In it, a loop radiator located close to the active HF radiator is a passive HF radiator. It enables to provide better coupling between active and passive HF radiators. The passive LF radiator still has a micro-strip form.
[0055] The versions described in FIGS. 2-6 can be used for making dual-band antennas.
[0056] Another embodiment is shown in FIG. 8 . A loop radiator of the HF band is active and excited similarly to the single-band variant. The loop radiator can have four excitation points that are powered from the loop radiator power circuit through two-wire lines.
[0057] Another embodiment of FIG. 9 shows passive loop radiators for LF and HF bands. The use of active loop LF and HF radiators is possible with the corresponding power circuits of the loop radiators, two-wire transmission lines and dividing circuits for LF and HF bands. Dividing circuits ensure anti-phase addition of LHCP fields in the rear hemisphere for each band. Their inputs are the corresponding antenna inputs for each of the bands.
[0058] Antenna designs shown in the drawings have circularly-shaped ground plane, MP and loop radiators, but they are not limited by this shape and can have square, rectangular or any other similar shape.
[0059] FIGS. 10 and 11 show computational DD characteristics for the considered antenna designs and the prototype. Computational principles and main relationships are given below, in Annex 1.
[0060] FIG. 10 as an example illustrates DD computational results according to expressions (4)-(7) for the proposed design (square) and prototype ( FIG. 1 a ) (designated by circles), when diameters of the radiating patch and loop filter are equal to 0.2λ. In the proposed design, the loop radiator is equidistant from patches of radiator 201 and ground plane 202 ( FIG. 2 ). In an approximation of the computational model, there is no LHCP field in the proposed antenna design.
[0061] FIG. 11 shows antenna DD computational results for the design wherein the loop radiator is shifted towards ground plane 502 by 0.05λ. In this case there is LHCP field, but it is much less than in the conventional case.
Annex 1
[0062] A patch radiator is a resonator cavity formed by a ground plane and a radiating patch loading for slot radiation admittance. Slot radiation can be described as radiation of a magnetic current filament. If the radiating patch is circularly shaped, the magnetic current filament is a circle. When right-hand circularly polarized field is excited, the density of magnet current has an azimuthal dependence (in angle φ) of type e −iφ . A loop radiator can be presented as a ring of electric current whose density has also azimuthal dependence e −iφ .
[0063] Expressions for a directional diagram for magnetic and electric current can be obtained by integrating Green's function over area of the current source (see Y. T. Lo, S. W. Lee “Antenna Handbook” v. 2, Van Nostrand Reinhold, 1993). As a result we have:
[0000]
F
_
m
(
θ
)
=
θ
→
0
I
1
(
θ
)
+
ϕ
→
0
cos
(
θ
)
I
2
(
θ
)
i
(
1
)
F
_
e
(
θ
)
=
θ
→
0
(
-
cos
(
θ
)
I
2
(
θ
)
i
)
+
ϕ
→
0
I
1
(
θ
)
(
2
)
[0064] Expression (1) describes DD of magnetic current ring, and (2) describes DD of electric current ring. In (1) and (2) integration functions I 1 (θ) and I 2 (θ) from meridian coordinate θ are determined as follows:
[0000]
I
1
(
θ
)
=
1
π
∫
0
2
π
-
ϕ
kRsin
(
θ
)
cos
(
ϕ
)
cos
(
ϕ
)
ϕ
;
I
2
(
θ
)
=
1
π
∫
0
2
π
-
ϕ
kRsin
(
θ
)
cos
(
ϕ
)
sin
(
ϕ
)
ϕ
.
(
3
)
[0065] here R is the radius of the electric or magnetic current ring, k=2π/λ is the wavenumber, λ is the wavelength.
[0066] In practice, the radius of the loop radiator is a little larger than the radius of the radiating patch of the MP radiator. For the sake of simplification, they are assumed to be equal. Correspondingly, radii of the rings of electric and magnetic currents are equal too.
[0067] Antenna field can be represented as a sum of fields formed by MP and loop radiators:
[0000] {right arrow over (F)} (θ)= {right arrow over (F)} m (θ)+ A{right arrow over (F)} e (θ) e −ikh cos(θ) (4)
[0068] Here {right arrow over (F)}(θ) is the DD of MP radiator, {right arrow over (F)} e (θ) is the DD of the loop radiator, A is the amplitude multiplier which determines the excitation level of the loop radiator, e −ikh cos(θ) is the multiplier describing possible vertical isolation of MP and loop radiators which depends on the vertical distance h≧0 between MP and loop radiators. Angle θ is read out from the normal to the surface of the radiating patches. Value A is selected considering the absence of left polarization at θ=180°. To find it, vectors F m (θ) and F (θ) are written in the orthonormal basis formed by the vectors of right {right arrow over (r)} 0 and left {right arrow over (l)} 0 circular polarization:
[0000]
r
→
0
=
1
2
(
θ
⇀
0
-
ϕ
→
0
)
l
→
0
=
1
2
(
θ
⇀
0
-
ϕ
→
0
)
[0069] Then from (1) and (2):
[0000] F m (θ)= {right arrow over (r)} 0 I a (θ)+ {right arrow over (I)} 0 iI b (θ) (5a)
[0000] F e (θ)= {right arrow over (r)} 0 iI a (θ)+ {right arrow over (l)} 0 I b (θ) (5b)
[0070] Here:
[0000]
I
a
(
θ
)
=
1
2
(
I
1
(
θ
)
+
cos
(
θ
)
I
2
(
θ
)
)
I
b
(
θ
)
=
1
2
(
-
I
1
(
θ
)
+
cos
(
θ
)
I
2
(
θ
)
)
[0071] From (4), the full field is:
[0000] {right arrow over (F)} (θ)= {right arrow over (r)} 0 I a (θ)(1 +Aie −ikhcos(θ) )+ {right arrow over (l)} 0 I b (θ)( i+Ae −ikhcos(θ) ) (6)
[0072] Considering the condition of vanishing left polarized constituent of the vector results in:
[0000] A=−ie −ikh (7)
[0073] Then
[0000] F (θ)= {right arrow over (r)} 0 I a (θ)(1 +e −ikh[ cos(θ)+1] )+ {right arrow over (l)} 0 iI b (θ)(1 −e −ikh[ cos(θ)+1] ) (8)
[0074] From (8) it is seen that at the left polarized component becomes zero at any random θ, and the right polarized component doubles. This means that there is full subtraction of LHCP fields of MP and loop radiators and following addition of their fields of RHCP in the full sector of angles 0. This case corresponds to the embodiment with active excitation of the loop radiator when the loop radiator is located in the horizontal symmetry plane of the MP radiator.
[0075] Prototype DD can be described as a sum of fields for active and passive MP antennas, respectively:
[0000] {right arrow over (F)} (θ)= {right arrow over (F)} ma (θ)+ A{right arrow over (F)} mp (θ) e −ikh cos(θ) (9),
[0076] Here {right arrow over (F)} ma (θ) is the DD of active MP radiator, {right arrow over (F)} mp (θ) is the DD of passive MP radiator, A is the amplitude multiplier determining the excitation level of the passive radiator, e −ikh cos(θ) is the multiplier describing vertical isolation of the active and passive radiators as a function of the distance h between them. Note that in this case h≠0, since the passive radiator is above the active one. {right arrow over (F)} ma (θ) and {right arrow over (F)} a (θ) are calculated according to (1). The amplitude multiplier A is selected considering the condition of absence of LHCP field at θ=180°. In this case
[0000] A=−e −ikh (10),
[0077] and full compensation for LHCP field is possible only at 0=180°.
[0078] Having thus described a preferred embodiment, it should be apparent to those skilled in the art that certain advantages of the described method and apparatus have been achieved.
[0079] It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. The invention is further defined by the following claims. | Patch antennas for signals of global navigation satellite systems (GNSS) are described. A compact antenna system reduces directional diagram level in the rear hemisphere primarily for cross-polarized (left hand circularly-polarized) component. It can be used for reducing multipath reception. The antenna receives GNSS signals and includes a patch circularly-polarized radiator consisting of a radiating patch, a ground plane under it and a loop radiator coaxially located around the patch radiator. The loop radiator is excited by a separate power circuit or by a passive method where LHCP waves of MP and loop radiators in the rear hemisphere would be anti-phase added. A dual-band antenna system includes an active HF radiator, under which there is an active LF radiator under which there is a passive LF radiator, a loop HF radiator being coaxially located around the active HF radiator. | 7 |
This is a continuation-in-part of IME2000-007, Ser. No. 09/785,588, filing date Feb. 16, 2001 assigned to a common assignee now U.S. Pat. No. 6,432,695.
The invention relates to the general field of MEMS with particular reference to thermal cycling chambers for use in, for example, polymerase chain reactions as well as other reactions that involve thermal cycling.
FIELD OF THE INVENTION
PCR (Polymerase Chain Reaction) is a molecular biological method for the in-vitro amplification of nucleic acid molecules. The PCR technique is rapidly replacing many other time-consuming and less sensitive techniques for the identification of biological species and pathogens in forensic, environmental, clinical and industrial samples. PCR using microfabricated structures promises improved temperature uniformity and cycling time together with decreased sample and reagent volume consumption.
BACKGROUND OF THE INVENTION
An efficient thermal cycler particularly depends on fast heating and cooling processes and high temperature uniformity. Presently, microfabricated PCR is preferably carried out on a number of samples during a single thermal protocol run. It is a great advantage if each reaction chamber can be controlled to have an independent thermal cycle. This makes it possible to run a number of samples with independent thermal cycles simultaneously (parallel processing). The first work on multi-chamber thermal cyclers fabricated multiple reaction chambers by silicon etching. Although separate heating elements for every reaction chamber can be realized, it was impossible in these designs to eliminate thermal cross-talk between adjacent reaction chambers during parallel processing because of limited thermal isolation between reaction chambers. As a result, multiple chambers having independent temperature protocols could not be used. Additionally, temperature uniformity achieved inside the reaction chamber was ±5 K in this thermal isolation and heating scheme.
Integration of the reaction chamber with micro capillary electrophoresis (CE) is also an interesting subject, in which small volumes of samples/reagents will be required both for PCR and CE. Again, a high degree of thermal isolation is very important particularly where various driving/detection mechanisms prefer a constant room temperature substrate.
A number of microfabricated PCR devices have been demonstrated in the literature. Most of them were made of silicon and glass, while a few others were using silicon bonded to silicon. On-chip integrated heaters and temperature sensors become important in the accurate control of the temperature inside these small reaction chambers. Good thermal isolations have been proved promising for quick thermal response. Micro reaction chamber integrated with micro CE was only demonstrated where no PCR thermal cycling was performed (only slowly heated to 50° C. in 10-20 seconds and held for 17 minutes). Parallel processing microfabricated thermal cyclers with multi-chamber and independent thermal controls have not yet been reported.
A routine search of the prior art was performed with the following references of interest being found: Northrup et al. (U.S. Pat. No. 5,589,136 December 1996), Northrup et al. (U.S. Pat. No. 5,639,423, U.S. Pat. No. 5,646,039, and U.S. Pat. No. 5,674,742), and Baier Volker et al, in U.S. Pat. No. 5,716,842 February 1998), did early work on multi-chamber thermal cyclers fabricated by silicon etching. Baier et al. (U.S. Pat. No. 5,939,312 August 1999) describe a miniaturized multi-chamber thermal cycler. This latter reference includes the following features—1. multiple chambers placed together within a silicon block from which they are thermally isolated. This approach works against fast cycling because of slow cooling by the chambers. 2. The chambers are packed together very closely, with minimal thermal isolation from one another, so all chambers must always to be thermally cycled with the same thermal protocol. The individual chambers were not subject to independent thermal control of multi-chambers. 3. Baier's units have thin-film heaters that cover the whole bottom of the chamber (as in conventional heating designs). 4. Baier's apparatus is limited to the chambers, no micro-fluidic components (valves, fluidic manipulation, flow control, etc.) being included.
Micro-fabricated PCR reaction chambers (or thermal cyclers) have been reported in the technical literature by a number of experimenters, including: (1). Adam T. Woolley, et al, (UC Berkeley), “Functional Integration of PCR Amplification and Capillary Electrophoresis in a Microfabricated DNA Analysis Device”, Analytical Chemistry, Vol. 68, pp. 4081-4086, (2). M. Allen Northrup, et al, (Lawrence Livermore National Lab, UC Berkeley, Roche Molecular Systems), “DNA Amplification with a microfabricated reaction chamber”, 7th Intl. Conf. Solid-State Sensors and Actuators, pp. 924-926, (3). Sundaresh N. Brahmasandra, et al, (U. Michigan), “On-Chip DNA Band Detection in Microfabricated Separation Systems”, SPIE Conf. Microfuidic Devices and Systems, Santa Clara, Calif., September 1998, SPIE Vol. 3515, pp. 242-251, (4). S. Poser, et al, “Chip Elements for Fast Thermocycling”, Eurosensors X, Leuven, Belgium, September 96, pp.11971199. The latter showed promising results for use of well thermal isolation as a means for achieving quick thermal response.
Also of interest, we may mention: (5). Ajit M. Chaudhari, et al, (Stanford Univ. and PE Applied Biosystems), “Transient Liquid Crystal Thermometry of Microfabricated PCR Vessel Arrays”, J. Microelectromech. Systems, Vol. 7, No. 4, 1998, pp. 345-355, (6). Mark A Burns, et al, (U Michigan), “An Integrated Nanoliter DNA Analysis Device”, Science 16, October 1998, Vol. 282, pp. 484-486, and (7). P. F. Man, et al, (U. Michigan), “Microfabricated Capillary-Driven Stop Valve and Sample Injector”, IEEE MEMS'98 (provisional), pp. 45-50.
SUMMARY OF THE INVENTION
It has been an object of the present invention to provide a microfabricated thermal cycler which permits simultaneous treatment of multiple individual samples in independent thermal protocols, so as to implement large numbers of DNA experiments simultaneously in a short time.
A further object of the invention has been to provide a high degree of thermal isolation for the reaction chamber, where there is no cross talk not only between reaction chambers, but also between the reaction chamber and the substrate where detection circuits and/or micro fabricated Capillary Electrophoresis units could be integrated.
Another object has been to achieve temperature uniformity inside each reaction chamber of less than ±0.5 K together with fast heating and cooling rates in a range of 10 to 60 K/s range.
These objects have been achieved by use of a thermal isolation scheme realized by silicon etch-through slots in a supporting silicon substrate frame. Each reaction chamber is thermally isolated from the silicon substrate (which is also a heat sink) through one or more silicon beams with fluid-bearing channels that connect the reaction chamber to both a sample reservoir and a common manifold. Each reaction chamber has a silicon membrane as its floor and a glass sheet as its roof. This reduces the parasitic thermal capacitance and meets the requirement of low chamber volume. The advantage of using glass is that it is transparent so that sample filling and flowing can be seen clearly. Glass can also be replaced by any kind of rigid plastic which is bio- and temperature-compatible.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a shows a plan view of a first embodiment of the invention.
FIGS. 1 b and 1 c are orthogonal cross-sections taken through FIG. 1 a.
FIG. 2 is a closeup view of a portion of FIG. 1 a.
FIG. 3 illustrates the air injector and pressure valve part of the structure.
FIG. 4 shows a group of three cycling chambers integrated within a single unit.
FIG. 5 shows a full population of cycling chambers covering an entire wafer.
FIG. 6 illustrates how the resistor strips may be located inside slots in a conductive silicon beam.
FIG. 7 a shows a plan view of a second embodiment of the invention.
FIGS. 7 b and 7 c are orthogonal cross-sections taken through FIG. 7 a.
FIG. 8 is a closeup view of a portion of FIG. 7 a.
FIG. 9 is the equivalent of FIG. 1 for the second embodiment.
FIG. 10 shows the starting point for the process of the present invention.
FIGS. 11 and 12 illustrate formation of resistive heaters and temperature sensors.
FIGS. 13 and 14 illustrate the formation of the silicon membrane and etch-through slots that are needed to achieve a high level of thermal isolation for the chamber.
FIG. 15 shows how a sheet of dielectric material is bonded to the top surface to form the chamber.
FIG. 16 illustrates how connection to the outside world may be made to an array of recycling chambers.
FIG. 17 shows another approach to making connection to the outside world for an array of recycling chambers.
FIG. 18 schematically shows the flow of information into and out of the array.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The basic principle that governs the present invention is that the thermally conductive cycler chamber is thermally isolated from its surroundings except for one or more heat transfer members through which all heat that flows in and out of the chamber passes. Consequently, by placing at least one heating element in each transfer area, heat lost from the chamber can be continuously and precisely replaced, as needed. This is achieved by placing, within the chamber, at least one temperature sensor per heating element and locating this sensor close to the heating elements. Additionally, by connecting the heat transfer areas to a heat sink through a high thermal conductance path, the chamber can also be very rapidly cooled, when so desired.
Also included as part of the structure of the present invention is a fully integrated fluid dispensing and retrieval system. This allows multiple chambers to share both a common heat sink as well as an inlet fluid source reservoir with both fluid flow and temperature being separately and independently controllable. As a result, thermal cross-talk between chambers can be kept to less than about 0.5° C. at a temperature of about 95° C. while temperature uniformity within an individual chamber can be reliably maintained, both theoretically and experimentally, to a level of less than ±0.3 K.
We now disclose two embodiments of the present invention as well as a process for manufacturing part of the structure.
First Embodiment
Referring now to FIG. 1 a , the top-left portion is a plan view of the structure. Seen there is chamber 11 which is connected at both ends to silicon frame 1 through monocrystalline silicon beams 10 . Heaters 5 are at each end inside the heat transfer areas. The latter are discussed above but are not explicitly shown since they have been introduced into the description primarily for pedagogical purposes. In addition to the heaters, each chamber contains at least one temperature sensor 4 for each heating element 5 . They are located close to the heating elements, as shown.
Fluid bearing channels dispense fluid into and remove fluid from the chamber 11 . They are brought into the chamber through the silicon beams 10 . As can be more clearly seen in the closeup shown in FIG. 2, unprocessed fluid is stored in common reservoir 7 and is directed to chamber 11 through fluid-bearing channel 31 . Control of fluid flow is achieved by use of compressed gas (usually, but not necessarily, air), or hydraulic/pneumatic pressure with a gas-liquid interface at the valve, that connects gas source 25 to channel 31 through air injector 19 . Since the capillary force drives the fluid from reservoir 7 to valve 8 (FIG. 3 ), stopping there, an additional pressure impulse will help the fluid to pass through valve 8 and, after that, no more external pressure is needed as the fluid will continue to flow, being driven by capillary forces.
To prevent unintended entry of fluid into the chamber, pressure valves 8 , as seen in FIG. 1 c , are placed at both ends of the chamber. A closeup of the area contained within circle 33 of FIG. 2 is shown in FIG. 3 to illustrate how the valves operate. A short length 16 of the fluid-bearing channel is made narrower than the rest of the channel. When fluid coming from the right side reaches point 15 it will be drawn into 16 through surface tension (capillary action) if it wets the inside of the channel (i.e. channel walls are hydrophilic). Then, when the fluid reaches point 17 , the same surface tension forces that drew the fluid into 16 will act to hold it inside 16 and prevent it from proceeding down channel 13 . If the fluid finds the channel walls to be hydrophobic, then surface tension will act to keep it from entering 16 . Either way, additional pressure is needed to make the fluid pass through valve 8 . The recorded pressure barriers for water (about 6 kPa for valves, >10 kPa for the air injector) are enough to allow on-chip automatic control of fluid flow.
Returning now to FIG. 1 a , the fluid-bearing channel on the far side of chamber 11 is seen to terminate at local reservoir 9 . When fluid is forced into chamber 11 , the air that is already in the chamber is forced out and passes into local (sample) reservoir 9 where it is allowed to escape but without allowing any liquid to enter it. When temperature cycling has been completed, pressure for the air injector is used to transfer the sample from the chamber into reservoir 9 where it can be collected into a pipette/tube or other collector.
Referring now to FIG. 4, shown there is an example of several chambers integrated to form a single multi-sample recycling unit. As can be seen, the individual chambers 11 are positioned inside the interior open area of silicon frame 1 and are connected to it through silicon beams 10 . It is important to note that, except for these beams, the chamber is always thermally isolated from the frame by open space 3 (shown as a thin slot in FIG. 2 ). FIG. 5 shows how the sub-structure seen in FIG. 4 appears when full wafer 66 of silicon has been used to form multiple chambers.
Returning once more to FIG. 1 c , as can be seen, the part of the chamber between valves 8 (where the actual temperature cycling occurs) is effectively a sandwich between glass plate 2 and silicon membrane 12 which is only between about 30 and 100 microns thick. This arrangement enables the physical volume (less than about 100 micro-liters) and thermal capacitance of the chamber to be kept to a minimum.
Also seen in FIG. 1 b are bonding pads 6 . These facilitate the bonding of glass sheet 2 to the silicon. As a feature of the present invention these pads are placed inside trench 18 as illustrated in FIG. 6 . These facilitate the application of anodic bonding to our structure. Anodic bonding is an excellent bonding technique that allows high stability at high temperature in various chemical environments as no polymer is used. The silicon and glass wafers are heated to a temperature (typically in the range 300-500° C. depending on the glass type) at which the alkali metal ions in the glass become mobile. The components are brought into contact and a high voltage applied across them. This causes the alkali cations to migrate from the interface resulting in a depletion layer with high electric field strength. The resulting electrostatic attraction brings the silicon and glass into intimate contact. Further current flow of the oxygen anions from the glass to the silicon results in an anodic reaction at the interface and the result is that the glass becomes bonded to the silicon with a permanent chemical bond.
Note that although we exemplify sheet 2 as being made of glass, other materials such as rigid plastics, fused quartz, silicon, elastomers, or ceramics could also have been used. In such cases, appropriate bonding techniques such as glue or epoxy would be used in place of anodic bonding.
Finally, in FIGS. 1 b and 1 c we note the presence of heat sink 14 to which the silicon frame 1 is thermally connected. An important advantage of this arrangement is that silicon substrate 1 can be kept close to room temperature rather than near the temperature of the reaction chamber during heating. This facilitates integration of the PCR thermocycler with other parts of micro total-analysis-system (PTAS) on a single chip, as well as for multi-chamber reaction with independent thermal control, as discussed earlier.
Second Embodiment
The second embodiment of the invention is generally similar to the first embodiment except that, instead of being connected to the silicon frame through two silicon beams, only a single cantilever beam is used. This has the advantage over the first embodiment that elimination of asymmetry due to fabrication/packaging and heating is achieved, resulting in easier control and uniformity of temperature. It is illustrated in FIGS. 7 a-c and, as just noted, most parts marked there are the same as those shown in FIGS. 1 a-c.
Since there is only one silicon beam available, it has to be used for both introducing as well as removing liquid to and from the chamber. This has been achieved by the introduction of baffle 76 that is parallel to the surface of the chamber (at the transfer area) and that is orthogonally connected to the transfer area by a sheet of material 84 that serves to separate incoming from outgoing liquid. Its action can be better seen in the closeup provided by FIG. 8 . As in the first embodiment, liquid from common reservoir 7 is sent along channel 31 into the chamber. An air injector is also used to accomplish this although it is not shown in this figure. When the incoming liquid enters the chamber it is directed by baffle 76 to flow in direction 81 .
Emptying of the chamber is accomplished in a similar manner to that of the first embodiment except that local sample reservoir 9 is on the same side as the inlet reservoir 7 . When the chamber is to be emptied, baffle 76 again directs the flow of liquid, this time in direction 82 . Seen in FIG. 7 c , but not shown in FIG. 8, is valve 8 . There are, of course, two such valves, as in the first embodiment, but the one that can be seen is blocking a view of the other one.
FIG. 9 is analogous to FIG. 4 and illustrates a group of three cycling chambers 11 suspended within the interior open area of silicon frame 1 which is itself part of a full silicon wafer.
Process for Manufacturing the Invention
We now describe a process for manufacturing the frame portion of the structure of the invention. Before proceeding we note that all figures that follow (FIGS. 10-15) show only the right hand side of the chamber but, since the left side is a mirror reflection of the right side, the process for manufacturing the entire chamber is readily envisaged.
Referring now to FIG. 10, process begins with the provision of silicon wafer 101 , between about 350 and 700 microns thick, in whose upper surface, two inner trenches 103 and two outer trenches 104 are etched to a depth of between about 0.1 and 1 microns. The width of inner trenches 103 is between about 20 and 500 microns while that of outer trenches 104 is between about 50 and 500 microns.
Next, dielectric layer 102 is formed over the entire surface. Its thickness is between about 0.02 and 0.5 microns. Our preferred material for dielectric layer 102 has been silicon oxide formed by thermal oxidation or CVD (chemical vapor deposition) but other materials such as phosphosilicate glass (PSG), silicon nitride, polymers, and plastics could also have been used.
Next, as seen in FIG. 11, a layer of a material that is suitable for use as a temperature sensor (thermistor) 105 and also as a resistive heater is deposited to a thickness between about 1,000 and 10,000 Angstroms. Our preferred material for this has been aluminum but other materials such as gold, chromium, titanium, or polysilicon could also have been selected. This layer is then patterned and etched to form temperature sensors and the heater element. Bonding strips 106 are also shown.
Moving on to FIG. 12, two top preliminary trenches 112 are then etched into the top surface to a depth of between about 30 and 100 microns and a width of between about 20 and 100 microns. The trenches 112 are located between inner trenches 103 and outer trenches 104 , each about 100 microns from the inner trench.
Next, as seen in FIG. 13, the upper surface of the wafer is patterned and etched to form chamber trench 113 . This is centrally located between the inner trenches 103 and is given a depth between about 30 and 500 microns and a width between about 100 and 10,000 microns. Trench 112 is not protected while trench 113 is being formed so that at the end of this step in the process, its depth will have increased. Also at this stage, second dielectric layer 132 is formed on all surfaces that don't already have a dielectric layer on them. Its thickness is between about 1,000 and 5,000 Angstroms. In FIG. 13, the newly extended and lined trench 112 is now designated as trench 131 . Its depth is between about 60 and 600 microns.
Referring now to FIG. 14, the lower surface of the wafer is patterned and etched to form under-trench 141 . This is wide enough to slightly overlap the top preliminary trenches 131 and it is deep enough so that, at the completion of this step, trench 131 will be penetrating all the way through to the wafer's under-side and the wafer thickness (under trench 113 ) will have been reduced to between about 30 and 100 microns. In this way, silicon membrane 12 and frame 1 , as shown in earlier figures, will have been formed.
The final step in the process is illustrated in FIG. 15 . Sheet of dielectric material 152 is micro-machined to form holes in selected locations (as an example, see 9 in FIG. 1) and then bonded to the wafer to form a hermetically sealed chamber that is thermally isolated from the wafer by slot 3 . For sheet 152 , our preferred material has been glass which we then bonded to the wafer by means of anodic bonding. However, as noted earlier, other materials such as rigid plastics, fused quartz, silicon, elastomers, or ceramics could also have been used. In such cases, appropriate bonding techniques such as glue or epoxy would be used in place of anodic bonding. Finally, an etching step is used to remove the second dielectric layer 132 in the open areas that contain bond-pads for electrical connections.
Connecting the Array to the Outside World
FIG. 16 shows the first of two possible ways to arrange the multi-chamber thermal cycler relative to the heat sink 14 and the electric lead-outs. In both ways, the thermal cycler array is mounted onto heat sink 14 with a thin layer of thermally conductive soft material 101 for better mechanical and thermal contact. This is to ensure that the local substrate 1 has very small thermal resistance to the heat sink 14 everywhere. Suitable materials for layer 101 include thermal conductive tapes, greases, glues, polymers, elastomers, rubber, and plastics. The thickness of layer 101 is typically between about 1 and 100 microns and its thermal conductivity is between about 0.2 and 20 W/m.K. It has a softness value between about 1 and 100 units on a Shore D Durometer.
Electric bond-pads 6 can be connected to the connectors 105 (metal pads/tracks) on the controller board 103 (e.g. a printed circuit board or PCB) through wire-bonding to probing-card 102 .
Metal lead-outs can be on top or on bottom side of the controller board 103 , or on both sides, connected through via 104 . Or the bond-pads 6 can be conducted out to the controller board 103 through a fixture of the type shown in FIG. 17 ), where flexural electric connector 106 (e.g., probe/tip/bump) from the board 103 can be pressed directly on top of the corresponding bond-pads 6 on the thermal cycler chip. Additionally, the spacer 107 can be made flexible in the thickness direction for better mechanical contact between the connectors 106 from the controller board 103 and the bond-pads 6 from the thermal cycler chip.
FIG. 18 illustrates the configuration of the control system for multi-chamber independent thermal protocol control. Connectors 105 on the controller board 103 for all the sensors of the N-chamber thermal cycler are directed to the electronic circuit for temperature sensing. Typically, at least one sensor and one heater are needed for each chamber. Then the analog outputs of the sensors (at least N channels) are translated into digital data through analogue-to-digital (A/D) converter and sent to the processor (or computer). A LabView programmed multi-channel parallel PID (proportional-integral-derivative) controller, for example, will manage to follow the expected thermal protocols for the N chambers through the real-time updated/refreshed output signals for the (at least) N-channel heaters. These signals flow to the electronic circuit for updated/refreshed heating, after conversion to analogue signals in the DIA converter (having at least N-channels). Consequently this is a close-loop multi-channel parallel processing control system, particularly for multi-chamber thermal cyclers having independent multiplexing or parallel processing. The number of channels, N, will generally be from 2 to 96 or 2 to 384, when used in current macro thermal cycler machines.
Results
By using the above described structures and manufacturing process, we have been able to both build and simulate units that meet the following specifications:
Heating power: <1.7 Watt;
Heating voltage: 8 volts
Ramp rate: 15-100° C/s;
Cooling rate: 10-70° C./s
Temperature uniformity: < ±0.3° C. (accuracy ± 0.2° C.)
Cross-talk: <0.4° C. at 95° C.
The effectiveness of the units for Micro PCR use reaction was verified with the Plasmid/Genomic DNA reaction and agarose gel electrophoresis. The result was adequate amplification in a reduced reaction time relative to existing commercial PCR machines. It was also confirmed that the units may be reused after cleaning.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. The miniaturized thermal cycler of the present invention may, for example, be used as a thermal cycling chamber for various types of biological and/or chemical reactions. | The invention describes a thermal cycler which permits simultaneous treatment of multiple individual samples in independent thermal protocols, so as to implement large numbers of DNA experiments simultaneously in a short time. The chamber is thermally isolated from its surroundings, heat flow in and out of the unit being limited to one or two specific heat transfer areas. All heating elements are located within these transfer areas and at least one temperature sensor per heating element is positioned close by. Fluid bearing channels that facilitate sending fluid into, and removing fluid from, the chamber are provided. The chambers may be manufactured as integrated arrays to form units in which each cycler chamber has independent temperature and fluid flow control. Two embodiments of the invention are described together with a process for manufacturing them as well as two schemes for making connections to the outside world. | 1 |
BACKGROUND AND OBJECTS
The present invention pertains to earth working apparatus and more particularly to a self-propelled soil stabilizer which pulverizes and mixes soil over which it travels.
Soil stabilizers are commonly utilized to treat earth by breaking up clumps and effecting a thorough mixing of the soil. Traditionally, soil stabilizers comprise a self-propelled vehicle which propels a rotor having a horizontal axis of rotation. The rotor is driven so that teeth thereon pulverize and mix the soil as the vehicle traverses the ground surface. Exemplary of known soil stabilizer design is that disclosed in U.S. Nelson Pat. No. 3,795,279 issued Mar. 5, 1974 and owned by the assignee of this invention. The disclosure of this patent is incorporated herein by reference as if set forth at length.
Generally, soil stabilizers heretofore proposed have involved a rotor designed for operation in a single direction, whether it be forward or reverse, with the teeth being oriented accordingly. It has been found, however, that depending upon certain variables, such as soil composition and the desired soil treatment for instance, one stabilizer may be less effective than another having an oppositely rotatable rotor. Consequently, the versatility of known stabilizers is considerably limited.
It would be desirable, then, to enhance the versatility of a stabilizer. Moreover, it is desirable that this be accomplished without requiring complex equipment or excessive efforts on the part of an operator to adapt the stabilizer to different conditions.
It is, therefore, an object of the present invention to minimize or obviate problems of the type previously discussed.
It is another object of the invention to provide a novel soil stabilizer.
It is an additional object of the invention to provide a novel stabilizer whose rotor can be easily adapted for rotation in different directions.
It is a further object of the invention to provide a novel mount for a stabilizer tooth.
It is still another object of the invention to provide a novel tooth mounting which effectively retains a tooth during a soil treating operation and promotes rapid reorientation of the tooth for opposite rotation of the rotor.
It is yet another object of the invention to provide a novel tooth mount which effectively retains a tooth absent the need for a separate fastener.
BRIEF DESCRIPTION OF INVENTION
These and other objects are achieved by the present invention wherein a bi-directional rotor is provided with a tooth holder having generally oppositely directed tooth-receiving sockets. A tooth is received in one of the sockets to project toward the direction of rotation. When the rotational direction of the rotor is reversed, the tooth is removed and replaced in the other socket.
In another aspect of the invention, the sockets are tapered to receive a complementarily tapered tooth. The sockets intersect so that an interruption is formed in the tapered connection between the tooth and socket intermediate the ends thereof to provide for two-zone engagement which tends to compensate for manufacturing variances in the tapered fit.
THE DRAWING
Other objects and advantages of the present invention will become apparent from the subsequent detailed description thereof in connection with the accompanying drawings in which like numerals designate like elements, and in which:
FIG. 1 is a side elevational view of a rotor section of a soil stabilizer according to the present invention;
FIG. 2 is a view of the rotor taken from above the dirt cover removed;
FIG. 3 is a side view of a one-piece holder according to the present invention, depicting in phantom two types of teeth alternately mountable therein.
FIG. 4 is a front view of the one-piece holder taken in the direction 4--4 in FIG. 3;
FIG. 5 is a front view of the holder socket taken in the direction 5--5 in FIG. 3;
FIG. 6 is a rear view of the holder socket taken in the direction 6--6 in FIG. 3;
FIG. 7 is a side elevational view of one section of a two-piece holder;
FIG. 8 is a front view of the two-piece holder in an assembled condition;
FIG. 9 is a bottom view of the two-piece holder in an assembled condition;
FIG. 10 is an isometric view of the one-piece holder;
FIG. 11 depicts part of a first hydraulic circuit for operating the tor; and
FIG. 12 depicts a second hydraulic circuit for operating the rotor.
DETAILED DESCRIPTION
A soil stabilizer machine 10 (FIG. 1) according to the present invention comprises a suitable self-propelled vehicle such as a tractor 12. The tractor 12 may be of the type having a pair of drive wheels 16. A U-shaped or goose-neck frame 18 is rigidly attached to and extends rearwardly from the tractor body and carries a pair of rear support wheels (not shown). Connected to the tractor are a pair of drawbars 20 (FIGS. 1 and 2) which extend rearwardly from the tractor and carry at their rearward ends a horizontal cross-tube 22. Rotatably mounted on the ends of the cross-tube are a pair of lifting arms 24.
The lifting arms 24 carry a soil stabilizer unit 23 which includes a horizontal rotor 26. The rotor is mounted in the rear ends of the lifting arms 24 by rotary bearings 25.
The rotor 26 comprises a horizontal shaft carrying a plurality of hub members 29. A plate 30 is bolted to each hub and has a plurality of tooth holders 32 rigidly secured at spaced locations around the plate periphery. If desired, the hubs 29 can be eliminated, and the plates 30 could be welded directly to the rotor 26. Each tooth holder 32 is adapted to carry a tine or tooth 34 for working the soil, as will be discussed subsequently in greater detail.
The rotor 26 is rotated by one or more low speed, high torque hydraulic motors 36. A pair of such motors can be provided and are mounted on the lifting arms 24. Preferably, the output shafts of the motors 36 are directly connected to the ends of the rotor shaft 26, although any suitable coupling arrangement between the motors and the rotor could be provided.
The motors 36 can be driven in any convenient fashion, such as by hydraulic systems depicted in FIGS. 11 or 12. Many details of the FIG. 11 system are fully described in the aforementioned Nelson patent and need not be described at length herein. Briefly, though, the system includes a hydraulic pump 42 which is connected by fluid lines 44 and 46 to a cross-over relief valve 48 and the latter is connected by hydraulic fluid lines 50, 52 to a manually operable series parallel two-speed rotor speed range selection valve 54. The valve 54 controls the speed range of the motors 36. When the valve 54 is open, the motors 36 are rotated to drive the rotor 26. Suitable means is provided for reversing the direction of rotation of the motors 36. For example, a pair of reversing valves 60 can be provided in the hydraulic circuit and controlled by a suitable control at the operator's console. Preferably, the valves are connected together to operate in unison. In one position of the reversing valves 60 the rotor is rotated in one direction (e.g., clockwise ad viewed in FIG. 1). By reversing the valves 60 the rotor 26 can be made to rotate in the opposite direction (e.g., counterclockwise as viewed in FIG. 1).
Alternatively, a drive control for the pump 42 can be provided to selectively rotate the pump 42 in either direction so as to reverse the direction of the motors 36.
Alternatively, an open loop hydraulic system can be employed, as illustrated in FIG. 12. In this system, a fixed displacement pump A is connected to a four-way, three-position, spring centered directional control valve B. A return line C is connected to a reservoir R through a fluid cooler D and a filter E. The valve B is situated at the machine operator's console and can be selectively actuated to reverse the direction of rotation of the motors 36. A pressure relief valve F is provided which protects the pump and motors from over-pressure.
It will be appreciated that other arrangements will be apparent to one skilled in the art for reversing the rotary direction of the rotor 26.
A dirt shield 68 is connected to the lifting arms 24.
Suitable raising and lowering devices, such as hydraulic piston-cylinder assemblies are connected between the tractor and the lift arms for raising and lowering the stabilizer unit 23.
Referring now to FIGS. 3-6 and 10, a tooth holder 32 of one-piece construction will be described. The tooth holder 32 can be formed by casting and comprises a body portion 70 having a pair of mutually angled mounting surfaces 72, 74, first and second receiving surfaces 76, 78 extending respectively, at right angles relative to the mounting surfaces 72, 74, a top surface 80, and first and second transition walls 82, 84 extending between the top surface 80 and the first and second receiving surfaces 82, 84, respectively.
A pair of intersecting sockets 86, 88 are formed in the body 70. Each socket 86 has a forward end 90 formed in the first and second receiving surfaces 76, 78 and a rearward end 92 formed in the first and second transition walls 82, 84.
The sockets 86, 88 are essentially coplanar and extend at an angle relative to one another. An angle of forty degrees has been found desirable in one preferred form of the invention. Each socket 86, 88 includes a generally annular shank receiving portion 100 and a generally rectangular key receiving portion 102 extending from the shank receiving portion 100 (FIG. 4). The shank receiving portion 100 tapers inwardly from the forward end 90 to the rearward end 92 in generally frusto-conical fashion.
The sockets 86, 88 are each adapted to receive a ground-working tooth W, for example, either of those depicted in FIG. 3. Such a tooth is conventional and has a cutter head 106, a mounting shank 108 and a key 110. The mounting shank 108 is tapered frusto-conically in generally complementary fashion to each shank receiving portion 100 of the sockets so as to be capable of being forced or wedged into the socket to effect a tight friction fit therein. The key 110 of the tooth enters the key receiving portion 102 of the socket to prevent rotation of the tooth in its socket. Such knock-in, knock-out teeth are conventional and need not be described in further detail.
When installed within a socket 86 or 88, a back end of the tooth shank 108 projects from the rearward end 92 of the socket and is adapted to be engaged by a removal tool, such as a hammer. Since the sockets 86, 88 intersect, the holder carries only one tooth at a time.
In FIGS. 7-9, there is depicted an alternate form of holder 118 which is fabricated of two sections 122, 124 as by forging, for example. These sections 122, 124 are joined along a plane which extends end-to-end through the socket. Each section 122, 124 is provided with recesses 121 which, when the sections 124, 122 are mated, define V-notches 130 around the periphery of the holder for the reception of weld joints W.
Internally, the two-piece holder, once assembled, is essentially the same as the one-piece holder 32, and the parts thereof have been designated by similar numerals.
Since the sockets 86, 88 of the holders 32 or 118 intersect, the contact area between the tapered shank 108 of the tooth and the shank-receiving portion 100 of the socket is interrupted along an intermediate zone 114 defined by the intersection of the sockets 86, 88 (see FIG. 7).
It has been found that these zones of interruption contribute to the effective securement of the tooth within the socket. That is, such an interruption tends to compensate for manufacturing variations in taper of the tooth or socket and divides the tapered contact in separate segments located on opposite sides of the interruption. This enhances the ability of the socket to grip more firmly the shank of a tooth when normal tolerance variations are involved. Hence, the need for a separate fastener is avoided.
It will be realized that when reversal of a tooth W is desired, it is merely necessary that the tooth be knocked from its socket and then knocked into the opposite socket of the associated holder. Consequently, the rotor 26 will be adapted for reverse rotation with the teeth still located in an optimum cutting angle. This can be achieved in a minimum amount of time, thereby considerably enhancing the versatility of the rotor.
In operation, the rotor 26 is rotated in a direction suited to the nature of the soil being worked and the desired soil condition to be achieved, among other factors. The tooth holders 32 each carry a single tooth projecting toward the direction of rotation. That is, the cutting head of the tooth will be pointed in the direction of rotation. The teeth will be secured by a tapered, friction fit which is interrupted intermediate the ends of the tooth shank due to the criss-crossing or intersecting nature of the sockets 86, 88. In this manner, manufacturing variations in taper will tend to be compensated for.
If the direction of rotation of the rotor is to be reversed, it is merely necessary to knock each tooth from its holder and insert it in the other socket so as to project in the opposite direction, i.e., it will project in the new direction of rotation. There will again be present an interruption in the tapered engagement between the tooth and socket to provide for a two-zone frictional contact.
Although the invention has been described in connection with a preferred embodiment thereof, it will be appreciated by those skilled in the art that additions, modifications, substitutions and deletions not specifically described may be made without departing from the spirit and scope of the invention as defined in the appended claims. | A soil stabilizer comprises a self-propelled vehicle, a rotor having soil-working teeth, and a motor for driving the rotor. The motor is reversible to drive the rotor in opposite directions. The rotor includes tooth holders, each having generally oppositely directed tapered sockets. A tooth is received in one of the sockets so as to project in the direction of rotation. The rotor can thus be effectively utilized in either direction of rotation. The sockets are coplanar and intersect so that the zone of intersection forms an interruption in the tapered engagement between the tooth and socket intermediate the ends thereof to compensate for manufacturing variations in the tapered fit. | 4 |
FIELD OF THE INVENTION
The invention generally relates to a reciprocating (stroke) piston for a reciprocating piston compressor for generating compressed air for a vehicle, especially, a commercial vehicle.
BACKGROUND OF THE INVENTION
In a piston compressor, the reciprocating piston comprises a piston body having a piston head, a piston skirt with piston skirt walls and preferably pin bosses for receiving a gudgeon pin. At least two, preferably three, piston rings, can be introduced into encircling ring grooves in the piston body, of which at least the piston ring closer to the piston head is a compression ring and at least one piston ring, preferably the piston ring closest to the piston skirt, is an oil control ring. Lands are provided on the piston body between each pair of ring grooves and between the piston head and the ring groove arranged closest to the piston head, and on that side of the ring groove arranged closest to the piston skirt that faces away from the other ring groove or grooves.
In the case of a reciprocating piston compressor of the general type under consideration, there may be an unpleasant or toxic discharge of oil into the air. This discharged oil, which is carried in the air, can cause contamination of the systems supplied with this air or even of other, downstream systems, which can lead to problems that can be rectified only with great difficulty in servicing terms, and which can shorten the life of the systems. Also, this contaminated air may cause increased environmental pollution.
SUMMARY OF THE INVENTION
Generally speaking, it is an object of the present invention to improve the cleanliness of the air delivered in respect of the oil discharge described above.
According to an embodiment of the present invention, in a reciprocating piston of the general type under consideration, at least one of the lands of the piston body is set back from the diameter of the piston body by at least one recess, at least over a partial section of its land height, measured parallel to the axis of the piston body. This results in an overall improvement in the sealing behavior of the reciprocating piston. In particular, it is possible to achieve compensating volumes or flow cross sections in the zone of the piston rings (ring zone), by which it is possible to set specific ring interspace pressures and/or by which the flow behavior of oil-containing air in respect of oil discharge from the drive-side space of the reciprocating piston compressor is made more difficult.
According to an embodiment of the present invention, lands of the piston body are configured with different geometries by means of recesses and/or configured differently by means of recesses. By this, the flow cross sections of the reciprocating piston can be varied particularly well in order to improve the capability of the piston to prevent leaks in respect of any possible oil discharge or transfer or passage. The “fire land” of the reciprocating piston, which is situated between the piston head and the piston ring arranged closest to it, can also be included in these measures.
The recess in one of the respective affected lands (i) can be or have a step, (ii) can be or have a groove encircling the piston body, and/or (iii) can be or have a chamfer encircling the piston body.
A chamfer of this kind can be adjacent to a ring groove and/or can face or face away from the ring groove.
According to another embodiment, at least one recess can encircle the piston body in a rotationally asymmetrical and/or eccentric manner with respect to the axis of the piston body. In such case, different dimensions of the asymmetry and/or eccentricity can be provided, especially in the direction of connecting rod oscillation, in relation to the gudgeon pin direction of the reciprocating piston.
The orbital path of the recess can substantially follow an oval or an elliptical shape or a free form.
Irrespective of any asymmetry or eccentricity in respect of the overall orbital path of the recess, at least one recess can encircle the piston body with an inconstant recess depth, i.e., to have continuous or even section-wise differences in radial recess depth. It is ultimately also possible to achieve asymmetry or eccentricity itself by means of an inconstant recess depth.
For the capability of the reciprocating piston to prevent leaks, measures are also preferably taken as regards the associated piston rings or the selection thereof. It is possible for at least one piston ring to be designed as a compression ring, and for a taper-faced Napier ring to be provided for this purpose.
At least one other piston ring can be an oil control ring, and, for this purpose, can be a coil spring loaded slotted oil control ring, preferably a coil spring loaded double beveled oil control ring or a coil spring loaded beveled edge oil control ring. As a preferred option, two compression rings and one oil control ring can be used in order to maintain redundancy, particularly, in respect of the compression effect, if a piston ring breaks, for example.
According to a further embodiment, the coil spring loaded oil control ring provided as an oil control ring has at least two outward-projecting lands. Oil tightness in this region is thereby advantageously improved.
Preferably, the lands have land heights that, when measured parallel to the axis of the piston ring, correspond jointly to no more than 20% of the height of the piston ring and correspond individually to no more than 10% each of the height of the piston ring. However, further improvements can be achieved if the lands have land heights that, when measured parallel to the axis of the piston ring, are different.
In the case of a coil spring loaded double beveled oil control ring or coil spring loaded beveled edge oil control ring, which are provided as preferred options, the lands have connection angles, preferably, of 0 to 60 degrees. Connection angles of the lands could furthermore have a different and/or asymmetric angle size.
According to another embodiment, the oil control ring has at least one oil drainage facility, preferably, a plurality of oil drainage facilities, for the radial passage of oil. The oil drainage facility (facilities) can be embodied as a hole (holes) or as a slot (slots), for example. Oil transfer is thereby advantageously further reduced.
If, in addition, the ring groove provided for an oil control ring has at least one oil drainage facility, preferably, a plurality of oil drainage facilities, this respective oil drainage facility can be closed with respect to a hollow interior of the piston body. That is, for example, it can be designed to resemble a bowl or hay, or can lead into a hollow interior of the piston body, and, at the same time, an oil drainage facility of the oil control ring can preferably correspond at least partially to at least one oil drainage facility of the ring groove. The oil drainage facility of the ring groove can extend in the form of a slot in the circumferential direction of the ring groove.
Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification.
The present invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts, all as exemplified in the constructions herein set forth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in greater detail below using exemplary embodiments and with reference to the accompanying drawing figures, in which:
FIG. 1 shows a section through a reciprocating piston according to an embodiment of the present invention;
FIG. 2 shows the detail 1 b in FIG. 1 on an enlarged scale;
FIG. 3 shows a cross section through a compression ring designed as a taper-faced Napier ring;
FIGS. 4 a ) to d ) show further illustrative embodiments of details according to FIG. 2 ;
FIGS. 5 a ) to d ) and FIGS. 6 a ) to d ) show different possibilities for recess shapes in lands according to FIG. 1 or 4 ;
FIG. 7 shows a detail of a land with a recess in section;
FIG. 8 shows a circumferential line of the recess according to FIG. 7 in a plan view of the section line indicated by A, A in FIG. 7 ;
FIGS. 9 a ) to c ) show an exemplary oil control ring in various sectional and detail views;
FIG. 10 shows a sectional view of another illustrative embodiment of an oil control ring; and
FIG. 11 and FIG. 12 show two different examples of a ring groove for an oil control ring in section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a section through a reciprocating piston according to an embodiment of the present invention. The reciprocating piston has a piston head 1 a , pin bosses 1 c , a piston skirt with loadbearing piston skirt walls 1 d and box walls 1 e , which connect the piston skirt walls 1 d to the pin bosses 1 c.
Moreover, the reciprocating piston has a ring zone 1 b with three ring grooves, which are described in greater detail below. However, as shown in FIG. 1 , some of the lands delimiting the ring grooves can have recesses.
FIG. 2 show the ring zone 1 b according to FIG. 1 on an enlarged scale. The ring grooves are numbered as a first ring groove 1 , a second ring groove 2 and a third ring groove 3 , starting from the piston head 1 a . The lands delimiting the three ring grooves are likewise numbered consecutively as a first land 3 a 1 , a second land 3 a 2 , a third land 3 a 3 and a fourth land 3 a 4 . The first land 3 a 1 is the “fire land”. Lands 3 a 2 to 3 a 4 show examples of encircling recesses 3 b , which are set back or notched radially relative to the outer circumferential surfaces 3 c of the reciprocating piston. In the illustrative embodiment shown in FIG. 2 , the recesses 3 b are each set back in the form of steps.
The first ring groove 1 and the second ring groove 2 are provided for compression rings, which, as shown in section by way of example in FIG. 3 , can be designed as taper-faced Napier rings.
The third ring groove 3 is provided for an oil control ring of the kind shown, for example, in FIG. 9 or 10 .
FIGS. 4 a ) to d ) show further possible illustrative embodiments of a ring zone 1 b , in which the respective lands 3 a 2 to 3 a 3 show different possible cross sectional shapes of recesses 3 b . The fire land 3 a 1 can also have a recess. The lands 3 a 1 to 3 a 4 shown in FIGS. 4 a ) to d ) can also be varied independently of one another. Here, the reference signs correspond to those in FIG. 2 .
FIGS. 5 a ) to d ) show further possible cross sections of the recesses 3 b , in particular of the land below the compression piston ring grooves (first ring groove 1 and/or second ring groove 2 ).
FIGS. 6 a ) to d ) show further possible cross sections of the recesses 3 b , in particular for the land below the oil control piston ring groove (third ring groove 3 ).
In FIG. 5 a ), the diameter ØY of the recess 3 b is set back in the form of a step from the diameter ØX of the piston skirt or piston skirt wall 1 d (see FIG. 1 ), i.e., the diameter ØX of the piston skirt is greater than the diameter ØY of the recess 3 b . The configuration in FIG. 5 b ) is similar to that according to FIG. 5 a ), but, here, a chamfer at an angle α is provided between the diameter ØX and the diameter ØY. According to FIG. 5 c ), the recess 3 b is in the form of a groove, wherein the diameter ØY of the groove is less than the diameter ØX of the piston skirt. FIG. 5 d ) shows a combination of FIG. 5 a ) or 5 b ) and FIG. 5 c ), in which both the diameter ØZ of a groove of the recess 3 b and a region of the recess situated below the groove and having a diameter ØY are less than the diameter ØX of the piston skirt.
According to FIG. 6 a ), the diameter ØA of the recess 3 b is set back from the diameter ØB of the piston skirt or of the piston skirt wall 1 d (see FIG. 1 ) in the form of a step, i.e., the diameter ØB of the piston skirt is greater than the diameter ØA of the recess 3 b . The configuration in FIG. 6 b ) is similar to that according to FIG. 6 a ), but, here, a chamfer at an angle β relative to the third ring groove 3 is provided at the diameter ØB. FIG. 6 e ) is similar to FIG. 6 a ), but, here, the depth of the recess 3 b is less than in FIG. 6 a ), FIG. 6 d ) is a combination of FIG. 6 a ) or 6 c ) and FIG. 6 b ). Here, the diameter ØB of the piston skirt is once again greater than the diameter ØA of the recess 3 b and, in addition, a chamfer at an angle β is arranged between the diameter ØB of the piston skirts and the diameter ØA of the recess 3 b.
FIG. 7 shows a cross sectional view of any land between ring grooves having a recess 3 b with a section line A, A. If this section line A, A is viewed in accordance with FIG. 8 , it is clear from this example that the recess 3 b can also be formed asymmetrically and/or eccentrically with respect to the axis of the reciprocating piston. That is, the cutting depth of the recess 3 b can vary in size, for example, in the course of its orbit. In particular, an oval shape or elliptical shape of the recess orbit is conceivable. Here, the direction of the gudgeon pin is indicated by an arrow K and the direction of connecting rod oscillation is indicated by an arrow P.
FIGS. 9 and 10 show in section, on the one hand, an example of a coil spring loaded double beveled oil control ring ( FIG. 9 ) and, on the other hand, of a coil spring loaded beveled edge oil control ring ( FIG. 10 ) as a possible embodiment of an oil control ring. The examples of an oil control ring each have a main body 5 d or 9 d with two radially projecting lands 5 a, b and 9 a, b . Moreover, both illustrative embodiments have a spring element 5 e or 9 e . Respective holes 5 c and 9 c are provided between the lands 5 a , hand 9 a, b as oil drains in both examples. As FIGS. 5 b ) and 5 c ) show, these oil drains can be designed as holes 5 c 1 distributed over the circumference of the oil control ring or, alternatively, as more extended slots 5 c 2 .
The coil spring loaded double beveled oil control ring shown in FIG. 9 can, for example, be of a geometrical design such that the land height 5 d 1 of land 5 a added to the land height 5 d 2 of land 5 b is less than 20% of the ring height 5 f of the overall coil spring loaded double beveled oil control dog ring, wherein the respective land heights 5 d 1 and 5 d 2 are each only 10% of the ring height 5 f . If the ring height 5 f= 4 mm, for example, it follows that the land height 5 d 1 of land 5 a and the land height 5 d 2 of land 5 b must each be less than 0.4 mm.
The coil spring loaded beveled edge oil control ring shown in FIG. 10 can, for example, be of a geometrical configuration such that the land height 9 d 1 of land 9 a added to the land height 9 d 2 of land 9 b is less than 20% of the ring height 9 f of the overall coil spring loaded double beveled oil control ring, wherein the respective land heights 9 d 1 and 9 d 2 are each only 10% of the ring height 9 f . If the ring height 9 f= 4 mm, for example, it follows that the land height 9 d 1 of land 9 a and the land height 9 d 2 of land 9 b must each be less than 0.4 mm.
Preferably, lands 5 a, b and 9 a, b should have an axial height such that the respective land height is no more than 10% of the total height of the oil control ring and the land heights together are no more than 20% of this total height of the oil control ring.
The connection angles can vary, as is likewise indicated, merely by way of example, in FIGS. 9 and 10 .
Yet another possible example of a third ring groove 3 for an oil control ring is shown in section in FIGS. 11 and 12 . In these figures, the third ring groove 3 can also have at least one, preferably a plurality of, oil drain(s) 11 c and 12 c , which can pass through the piston skirt wall 1 d (in the case of 11 c ) or be designed as a blind hole (in the case of 12 c ) and can correspond at least partially to the oil drains 5 c ( FIG. 9 ) and 9 c ( FIG. 10 ) of the oil control ring.
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 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.
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 that, as a matter of language, might be said to fall therebetween. | A stroke piston for a stroke piston compressor for generating compressed air for a vehicle, such as a commercial vehicle, includes a piston body with a piston floor, a piston skirt with piston skirt walls and pin hubs for receiving a piston pin, and at least two piston rings, which can be inserted into circumferential ring grooves of the piston body. Ridges of the piston body are provided between each two ring grooves and between the piston floor and the first ring groove arranged closest to the piston floor and the ring groove arranged closest to the piston skirt facing away from the other ring groove or grooves. At least one of the ridges is recessed at least over a partial section of its ridge height, which is measured parallel to the axis of the piston body, with at least one recess relative to the diameter of the piston body. | 5 |
This application is a continuation, of application Ser. No. 562,818, filed Dec. 15, 1983, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a method of forming a thick film circuit pattern. In particular, the present invention relates to a method of forming a thick film circuit pattern with a sufficiently wide and uniformly thick film strip applied at a high speed with precision.
Conventional thick-film forming methods are broadly classified into screen printing method and nozzle drawing method. The screen printing method involves preparation of a new screen each time a new circuit pattern is developed. While screen preparation takes a substantial amount of time, the screen method allows highly efficient printing and for this reason this method has been extensively used in mass production. In the trail stage of development where repeated attempts are made to obtain a desired circuit pattern, the drawing method is employed to take its advantage in that it allows full utilization of the capability of a computer to draw a circuit pattern according to a program that can be easily changed.
As illustrated in FIG. 1, conventional drawing methods involve the use of a drawing nozzle 3 having a circular opening through which thick-film paste 1 is ejected onto a substrate 2 and the nozzle 3 is moved relative to the substrate to form a desired circuit pattern. Nozzles of this type are particularly useful for producing a pattern having a small width in the range from 25 micrometers to 150 micrometers. As shown in FIG. 2 where a typical example of the nozzle 3 is illustrated, the nozzle opening usually has a diameter in the range from 50 micrometers to 200 micrometers. However, a measurement made by a surface roughness meter after baking revealed that the cross-section of the deposited film pattern took the shape of a semicircle having a large thickness (see FIG. 3) at the center. This thickness increases as the diameter of the drawing nozzle increases, making it difficult to deposit a film strip with a wide and uniform thickness. In the case of a resistive paste used for depositing resistors, large thickness makes it difficult to trim the resistance value. Use of a high power laser would produce microscopic cracks in the crystalline structure of the film which might result in a gradual change in resistance value and could lead to the loss of device reliability. For most applications the required cross-section of resistive film strips is 12 micrometers or less in thickness and about 1.0 millimeter in width. However, use of a circular nozzle that meets the thickness requirement of less than 12 micrometers would only result in a strip with a width of only 150 micrometers. The current practice thus involves forming closely spaced parallel strips until a desired width is attained. However, this is time consuming and often results in nonuniform thickness causing film-to-film variations.
Another prior art method employing the drawing nozzle 3 is shown in FIGS. 4 and 5 in which a stylus 5 is attached to the tip of the nozzle. The nozzle is moved with the stylus 5 in contact with the surface of the substrate 2 so that the nozzle opening follows the contour line of the surface irregularities of the substrate. Alternatively, the nozzle 3 is tilted in a manner shown in FIG. 6 and moved to the right in order to follow the surface contour of the substrate. Although these methods have proved successful to achieve uniformity in thickness, the surface of the substrate is impaired as shown at 6 in FIGS. 6 and 7 along the path of the moving stylus and nozzle end and such impairment affects the electric characteristics of the resistance measured after the pattern is baked. Another disadvantage of these methods resides in the fact that since the substrate is formed of a hard material such as ceramic, the stylus and the nozzle end are worn out by contact therewith requiring frequent replacement and that the nozzle speed is limited by their relatively poor rigidity. Because of the various disadvantages noted above, the prior art drawing nozzle is not applicable to mass production.
SUMMARY OF THE INVENTION
The present invention contemplates the use of a drawing nozzle with an opening in the shape of a slit. The method of forming a thick film circuit pattern according to the invention involves moving the drawing nozzle of the above noted structure at a distance above the surface of a stationary substrate with the elongation of the slit opening being oriented at an angle to the direction of movement of the nozzle and forcing a paste in the nozzle downward through the slit opening onto the substrate to form a desired thick film circuit pattern. The paste is ejected at a speed lower than the speed at which the nozzle is moved for forming on the substrate a paste film having a thickness smaller than the dimension of the slit opening. The present invention additionally provides a method which involves measuring the distance from a given level to the surface of the substrate without contacting it to detect its surface irregularities and controlling the nozzle position above the substrate according to the detected surface irregularities while the nozzle moves along the path of a circuit pattern so that the nozzle slit opening follows a path closely parallel with the surface contour of the substrate.
The present invention allows circuit designers to choose from a plurality of the above nozzles having slit openings of different slit lengths so that a desired film width can be obtained by moving the nozzle over a single pass.
An object of the present invention is therefore to enable depositing on a substrate a thick-film circuit pattern having a sufficiently wide and uniformly thick film strip with a high operating speed and precision without causing impairment on the surface of the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described in further detail with reference to the accompanying drawings, in which:
FIG. 1 illustrates a prior art drawing method used in forming a thick film circuit;
FIG. 2 is a perspective view of the drawing nozzle employed in the prior art method of FIG. 1;
FIG. 3 is an illustration of the cross-section of a thick film strip deposited according to the prior art method of FIG. 1;
FIG. 4 illustrates another prior art drawing method employing a stylus attached to the tip of the nozzle of FIG. 2;
FIG. 5 illustrates the method of FIG. 4 in a perspective view;
FIG. 6 illustrates a further prior art drawing method;
FIG. 7 illustrates the method of FIG. 6 in a perspective view;
FIG. 8 illustrates in cross-section a drawing method according the present invention;
FIG. 9 illustrates the method of the invention in a perspective view;
FIG. 10 is a perspective view of the nozzle employed in the present invention;
FIG. 11 is a cross-sectional view of a thick film strip deposited according to the method of the present invention;
FIG. 12 is a perspective view of a drawing apparatus according to the invention;
FIG. 13 is a cross-sectional view of a drawing head of the invention; and
FIG. 14 is a block diagram of a control unit and associated devices.
DETAILED DESCRIPTION
Referring now to FIGS. 8 and 9, a drawing method according to the present invention is illustrated. Indicated at 7 in an upright position is a nozzle having a slit opening 8 at the lower end thereof. The interior of the nozzle 7 is such that the upper opening at 9 is also in the shape of a slit larger than the nozzle opening 7. A paste 1 is deposited on a length of the substrate 2 which is formed of an aluminium oxide. The paste 1 is electrically resistive and composed of a ruthenium oxide. As shown in FIG. 10, the slit opening 8 typically has a width of 0.1 millimeters and a length of 1 millimeter. The drawing nozzle 7 is formed of stainless steel.
According to an embodiment of the invention, the nozzle 7 was located 30 micrometers above the surface of the substrate and moved at a speed of 50 millimeters per second. The paste in the nozzle 7 was forced downward so that it was ejected through the nozzle opening under a pressure of 2 kilograms per square centimeter. FIG. 11 shows the cross-sectional view of the film strip formed according to the method performed under the above conditions. After baking a film strip of 10 micrometers thick and 1 millimeter wide was obtained.
Experiments showed that the width of the slit nozzle opening 8 is preferably in the range between 0.03 millimeters and 0.3 millimeters. More specifically, it was found no longer possible to obtain a sufficient amount of paste to be ejected with a slit opening of less than 0.03 millimeters even if the pressure applied to the nozzle is increased. With a slit opening of more than 0.3 millimeters it was found no longer possible to obtain a film thickness of 12 micrometers or less. The width of the slit opening 8 may vary in a range from 0.3 millimeters to 0.3 millimeters.
According to an alternative method of the present invention, the nozzle 7 is mounted on a vertical drive means, not shown, which is responsive to a signal applied thereto to move the nozzle 7 to adjust its height relative to the surface of the substrate 2. Prior to moving the nozzle 7, a measurement is made to detect the surface irregularities of the substrate 2 along the path of movement of the nozzle 7 by sending a laser beam from a laser measuring device and detecting the distance from a predetermined position to the surface of the substrate. From the laser measuring device is obtained a distance information signal which is applied to the actuator to operate it in a feedback loop. The vertical position of the nozzle 7 is controlled in accordance with the distance signal while it is moved along the path of the circuit pattern so that the slit opening 8 is kept a constant distance from the substrate following closely parallel with the surface contour line of the substrate. In an experiment, the slit opening 8 was able to maintain a distance of 30 micrometers from the substrate surface at all points. The preferred value of distance between the nozzle opening 8 and the surface of the substrate 2 was found to be in the range between 10 micrometers and 200 micrometers.
FIG. 12 shows a drawing apparatus employed in the present invention. The apparatus comprises a pair of support arms 10 and 11 mounted on a work bench 12. The arms 10 and 11 carry at their distal ends a laser head 13 and a drawing head 14, respectively. Below the heads 13 and 14 are provided an X-Y table 15 of a conventional design which moves in orthogonal directions by means of an X-axis motor 16 and a Y-axis motor 17. On top of the X-Y table 15 are located substrates 18 and 19 in positions below the laser head 13 and drawing head 14, respectively, so that both substrates are driven in the same orthogonal directions simultaneously. The substrate 18 is illuminated with a laser beam emitted from the laser head 13. This laser head is coupled to a known laser measuring device to detect the distance to the surface of the substrate 18 and feeds an output signal to a control unit to be described later and register data representing the surface irregularities of the substrate 18. After the surface irregularities are measured, the substrate 18 is moved to the position of the substrate 19 where the drawing paste is injected from variable height in response to the registered data.
As shown in FIG. 13, the drawing head 14 comprises a cylindrical core 20 and a moving coil structure formed by a slide shaft 21 and a coil 22 wound on a bobbin 23. The slide shaft 21 extends through the center of cylindrical core 20 so that the moving coil 22 is movable in the core spacing in vertical directions in response to a signal applied thereto from the control unit. A paste reservoir 24 carries the nozzle 7 and is secured to the moving coil structure and provided with an inlet 25 through which pressurized air is supplied from an air supply 26 which is controlled by the control unit, so that the paste in the reservoir 24 is forced downward through the nozzle 7 onto the substrate 19.
In FIG. 14, the control unit, designated at 30, comprises a microprocessor 31 and a memory 32. The laser measuring head 13 includes a laser 13a and an optical sensor 13b and an amplifier 13c connected to the sensor 13b. The microprocessor 31 controls the laser 13a to emit a laser beam to the substrate 18. The optical sensor 13b senses the reflection of the laser beam off the substrate 18 and applies an output through the amplifier 13c to the microprocessor 31. The microprocessor 31 is programmed in a well known manner to measure the surface irregularities of the substrate 18 and continuously generate distance data as the substrate 18 is moved in orthogonal directions. The distance data are sequentially fed to the memory 32 to record the irregularity data of each substrate prior to being subject to the drawing process.
The X-axis motor 16 and Y-axis motor 17 are controlled by a known X-Y driver 33 which is in turn controlled by position control signals supplied from the microprocessor 31. The moving coil 22 of the drawing head 14 is designated a Z-axis motor which is also controlled by the X-Y driver in response to the registered distance data read from the memory 32.
In operation, the programmed instruction of the microprocessor 31 instructs the motors 16 and 17 to move to specified locations of the substrate 18 according to the desired circuit pattern. Therefore, the registered distance data indicate the surface irregularities of the specified paths of the circuit pattern, rather than the entire surface of the substrate. The substrate 18 is then moved to the position of the substrate 19. The microprocessor reads the memory 32 to retrieve the recorded distance data of the substrate 18 now moved to the position of substrate 19 and feeds the retrieved data to the driver 33 to the Z-axis motor 22, while at the same time moving the X-Y table 15 to follow the specified paths. The surface irregularities could equally be as well measured with the use of any one of no contact measuring devices which utilize optial, ultrasonic or magnetic medium. | Disclosed is a method of forming a thick film circuit pattern according which involves moving a nozzle having a slit opening above the surface of a stationary substrate with the elongation of the slit opening being oriented at an angle to the direction of movement of the nozzle and forcing a paste in the nozzle downward through the slit opening onto the substrate to deposit a sufficiently wide and uniformly thick film strip. Preferably, the surface irregularities of the substrate are detected without contacting it for controlling the position of the slit opening above the substrate so that it follows closely parallel with the surface contour line of the substrate. | 7 |
This is a division of application Ser. No. 08/006,455, filed on Jan. 21, 1993, of Joe Barry Cockfield, Sabrina B. Fadial and Francis William Marco for METHOD AND APPARATUS TO CREATE AN IMPROVED MOIRE FABRIC.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for creation of moire fabric. Traditional moire fabrics are defined as a wavy or watered effect on textile fabric, especially a corded fabric of silk, rayon, or one of the manufactured fibers. An excellent example of a corded fabric would be a faille. Failles are generally defined as having fine, bright, continuous filament warps and coarse spun filling and a plain weave. This creates a noticeable ribbed effect in the filling direction. Other fabrics can be utilized with typically lesser results, however, a visible ribbed effect should be present in the fabric's filling.
Moire fabric falls into one of two categories. The first is an uncontrolled moire when the filling ribs of one layer of fabric is intentionally skewed with respect to the second layer of fabric prior to applying pressure to both layers of fabric. This will result in a significant increase in the number of filling ribs that cross with the associated increase in vertical moire lines. This is very undesirable since the appearance of the moire fabric will never be consistent and will vary from batch to batch.
Traditionally, controlled moire fabric is formed by selectively distorting or skewing small portions of the filling ribs so that the filling ribs only cross in selective areas. The most common method is the Francais bar method in which ribbed woven fabric is dragged over a stationary bar which has a series of knobs which are spaced at desired intervals. This is done at very high tension. The knobs distort the filling into a bow wherever they touch the fabric. When two pieces of this fabric are subjected to pressure, a traditional controlled moire will result that is typically found in upholstery, drapery, apparel, and other end uses. Problems with this type of moire patterning include the fact that the pattern is repeatedly fixed and dragging under high tension can damage and/or destroy the fabric.
Another traditional method utilized in creating controlled moire fabric is the "scratch" method. This is accomplished by means of a resilient roll having the desired designs embossed thereon. These designs may include flowers, geometrics, and so forth. While the fabric is in contact with this embossed roll, it is "scratched" with a series of steel blades which distort the filling yarns of the fabric according to the pattern embossed on the roll. Upon applying pressure to two pieces of this treated fabric, a moire pattern is produced. Once again, there is the problem of the destruction or damage to yarns by the steel blades and a fixedly repeatable pattern. This "scratch" method produces very poor results with a large quantity of broken filaments. The blades actually only contact the warp yarns thus producing a large amount of broken filaments with only minimal movement of the filling yarn. It is the movement of the filling yarn that is the desired result. Furthermore, by examination of faille fabric, the filling is virtually covered by warp yarns and thus it is very difficult to move the filling by mechanical means. Also, this "scratch" method creates fuzz on the surface of the fabric that results in less shine and poor moire patterns.
Yet another traditional method of producing a controlled moire is by that found in U.S. Pat. No. 2,448,145, which discloses the selective application of water to fabric with a noticeable ribbed effect in the filling direction. The fabric is then placed under high tension and then dried. This will distort the filling yarns in the wet areas differently than the filling yarns in the dry areas. Again, upon applying pressure to two pieces of this treated fabric, a moire pattern is produced. A severe problem with this technology is that it would be very difficult to selectively wet yarns while leaving adjacent yarns dry for a very precise pattern. Furthermore, stretching under high tension can severely weaken or even destroy filling yarns. Furthermore, this method is deficient in that it only works on fibers that absorb large amounts of water such as cotton, silk and so forth. Each pattern requires a specific patterning roll or screen which only changes the pick count slightly in the areas treated with water. While this may produce some beating when the fabrics are sandwiched and calendered it does not produce true moire because the filling is not distorted with bow or skew.
The present invention solves these problems in a manner not disclosed in the known prior art.
SUMMARY OF THE INVENTION
An apparatus and method for creation of moire fabric. This can be achieved by placing a first piece of fabric against a support member and directing at least one stream of fluid at the surface of said first piece of fabric to provide lateral yarn displacement. Then delivering said stream at a peak dynamic pressure in excess of about 300 p.s.i.g. and less than 4,000 p.s.i.g. and selectively interrupting and re-establishing contact between said stream and said surface in accordance with pattern information in order to pattern said first piece of fabric. This is followed by combining said patterned first piece of fabric with an unpatterned second piece of fabric in overlapping relationship and applying pressure by means of calender rolls having smooth surfaces to said combination of said first piece of patterned fabric and said second piece of unpatterned fabric.
It has been found that by using high pressure liquid jets having a moment of force in the plane of the fabric that there will be movement of the filling yarns in the fabric. This movement of the filling yarn is produced without damage to the warp yarns.
It is an unexpected advantage of this invention that surface fuzz on the fabric is forced to the back of the fabric. When high pressure liquid is applied to the fabric and subsequently the fabric is sandwiched and calendered, then beautiful moire patterns are produced. The absence of fuzz in the patterned areas produces especially bright and clear moire patterns.
Yet another advantage of this invention is to have moire patterns of any length or, in other words, patterns that do not necessarily repeat.
Still another advantage of this invention is the means of patterning is relatively nondestructive and places a minimum of tension on the fabric.
Another advantage of this invention is extremely precise since it can selectively move individual yarns.
A further advantage of this invention is that patterning can be extremely complex with the only limits being those of the human imagination.
Another advantage of this invention is that patterning can be altered while the machine is processing and downloaded in real time with the only limits being those of the complexity of the available computer system utilized in the storage and retrieval of moire patterns.
These and other advantages will be in part apparent and in part pointed out below.
BRIEF DESCRIPTION OF THE DRAWINGS
The above as well as other objects of the invention will become more apparent from the following detailed description of the preferred embodiments of the invention when taken together with the accompanying drawings, in which:
FIG. 1 is a schematicized side view of an apparatus for generating selectively patterned fabric wherein an array of liquid jets is placed inside a stencil in the form of a cylinder, which in turn is brought into close proximity to the fabric surface;
FIG. 2 is a diagrammatic perspective view of the apparatus of FIG. 1;
FIG. 3 is an overview of yet another apparatus which may be used to generate selectively patterned ribbed fabric disclosed herein;
FIG. 4 is a perspective view of the high pressure manifold assembly depicted in FIG. 3;
FIG. 5 is a side view of the assembly of FIG. 4, showing the alignment means used to align the containment plate depicted in FIG. 4;
FIG. 6 is a cross-section view of the assembly of FIG. 4, without the alignment means, showing the path of the high velocity fluid through the manifold, and the path of the resulting fluid stream as it strikes a substrate placed against the support roll;
FIG. 7 depicts a portion of the view of FIG. 6, but wherein the fluid stream is prevented from striking the target substrate by the deflecting action of a stream of control fluid;
FIG. 8 is an enlarged, cross-section view of the encircled portion of FIG. 7;
FIG. 9 is a cross-section view taken along lines XVII--XVII of FIG. 8, depicting the deflection of selected working fluid jets by the flow of control fluid;
FIG. 10 is a diagrammatic side view of two supply rolls, two calendering rolls and two take-up rolls;
FIG. 11 is a photomicrograph (1.1 x) of the face of the untreated faille fabric of Example 1;
FIG. 12 is a photomicrograph (1.1 x) of the face of the fabric of Example 1 after the step of selectively patterning the fabric by means of high pressure streams of liquid;
FIG. 13 is a photomicrograph (1.1 x) of the face of the fabric of Example 1 after the step of selectively patterning the fabric by means of high pressure streams of liquid and the step of calendering under one ton of pressure per linear inch with a second layer of the untreated fabric of FIG. 11;
FIG. 14 is a photomicrograph (1.1 x) of the face of the fabric of Example 2 after the step of selectively patterning the fabric by means of high pressure streams of liquid;
FIG. 15 is a photomicrograph (1.1 x) of the face of the fabric of Example 2 after the step of selectively patterning the fabric by means of high pressure streams of liquid and the step of calendering under one ton of pressure per linear inch with a second layer of unpatterned untreated fabric;
FIG. 16 is a photomicrograph (1.1 x) of the face of the fabric of Example 3 after the step of selectively patterning the fabric by means of high pressure streams of liquid; and
FIG. 17 is a photomicrograph (1.1 x) of the face of the fabric of Example 3 after the step of selectively patterning the fabric by means of high pressure streams of liquid and the step of calendering under one ton of pressure per linear inch with a second layer of patterned fabric.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the accompanying drawings, and initially to FIG. 1, which shows a schematicized side view of an apparatus for generating selectively pattern ribbed fabric wherein an array of liquid jets is placed inside a stencil in the form of a cylinder, which in turn is brought into close proximity to the fabric surface. The stencil is configured to allow the fabric to be patterned to be in the form of a moving web. FIGS. 1 and 2 show a configuration whereby a cylindrical stencil 40 is arranged to accommodate a multiple jet array orifice assembly such as shown at 32 within the stencil 40. In this configuration, orifice assembly 32 preferably comprises an array of jets which extends across the entire width of stencil 40, which in turn extends across the entire width of fabric web 26. Orifice assembly 32 is preferably located in close proximity to the inside surface of cylindrical stencil 40; the outer surface of stencil 40 is preferably located in close proximity to, and perhaps in direct contact with, the surface of fabric web 26. Means, not shown, are provided to achieve smooth rotation of stencil 40 in synchronism with the movement of fabric web 26. This may be achieved, for example, by an appropriate gear train operating on a ring gear which is associated with one or both ends of cylindrical stencil 40.
It is also contemplated that a single or multiple jet array may be used which is made to traverse within cylindrical stencil 40 so that the entire width of fabric web 26 may be treated. Use of such traversing jet or jet array would preferably require incremental movement of fabric web 26, as discussed above.
Where an array of high velocity jets may be individually controlled in response to pattern information, the apparatus shown in FIGS. 3 through 9, may be employed.
FIG. 3 depicts an overall view of an apparatus designed to use a combination manifold/stream forming/stream interrupting apparatus 50, which is depicted in more detail in FIGS. 4 through 9. Pump 8 is used to pump, via suitable conduits 4, 10, a working fluid such as water from a suitable source of supply 2 through an appropriate filter 6 to a high pressure supply duct 52, which in turn supplies water at suitable dynamic pressure (e.g., between 100 p.s.i.g. and 4,000 p.s.i.g.) to the manifold apparatus 50. Also, depicted in FIG. 3 are the conduits 136 for directing the control fluid, for example, slightly pressurized air as supplied from source 130, and valves 134 by which the flow of control fluid may be selectively established or interrupted in response to pattern information supplied by pattern data source 132. As will be explained in greater detail hereinbelow, establishing the flow of control fluid to manifold apparatus 50 via conduits 136, pressurized no higher than approximately one-twentieth of the pressure of the high velocity water, causes an interruption in the flow of high velocity water emanating from manifold apparatus 50. This will prevent the high velocity water from striking the substrate placed against backing member 21. Conversely, interrupting such control fluid flow causes the flow of high velocity water to impact the substrate 26 placed against backing member 21.
Looking to FIG. 4, it may be seen that manifold assembly 50 is comprised of five basic structures: high pressure supply gallery assembly 60 (which is mounted in operable association with high pressure supply duct 52), grooved chamber assembly 70, clamping assembly 90, control fluid conduits 136, and spaced barrier plate assembly 100.
Supply gallery assembly 60 is comprised of an "L"-shaped member, into one leg of which is machined a uniform notch 62 which extends, uninterrupted, along the entire length of the assembly 50. A series of uniformly spaced supply passages 64 are drilled through the side wall 66 of assembly 60 to the corresponding side wall of notch 62, whereby notch 62 may be supplied with high pressure water from high pressure supply duct 52, the side of which may be appropriately milled, drilled, and connected to side wall 66 and the end of respective supply passages 64. Slotted chamber assembly 70 is comprised of an elongate member having an inverted hook-shaped cross-section, and having an extending leg 72 into which have been machined a series of closely spaced parallel slots or grooves 74 each having a width approximately equal to the width of the desired high velocity treatment stream, and, associated with each slot, a series of communicating control fluid passages, shown in greater detail in FIGS. 6 through 9. These control passages are connected to control fluid conduits 136, through which is supplied a flow of low pressure control fluid during those intervals in which the flow of high pressure fluid flowing through slots 74 is to be interrupted.
As shown in FIGS. 6 through 9, the control fluid passages are comprised of a pair of slot intercept passages 76 spaced along the base of each slot and connected to an individual elongate chamber 78 which is aligned with the axis of its respective slot 74. Each slot 74 has associated with it a respective chamber 78, which in turn is connected, via respective individual control supply passages 80, to a respective control fluid conduit 136. In practice, chambers 78 may be made by drilling a passage of the desired length from the barrier plate (104) side of chamber assembly 70, then plugging the exit hole in a manner appropriate to contain the relatively low pressure control fluid.
Grooved chamber assembly 70 is positioned, via clamping assembly 90, within supply gallery assembly 60 so that its "C"-shaped chamber is facing notch 62, thereby forming a high pressure distribution reservoir chamber 84 in which, as depicted in FIGS. 8 and 9, high pressure water enters notch 62 via passages 64, enters reservoir chamber 84, and flows through slots 74 towards the substrate 26. Clamping assembly 90 is provided along its length with jacking screws 92 as well as bolts 94 which serve to securely attach clamping assembly 90 to supply gallery assembly 60 along the side opposite barrier plate assembly 100. It is important to note that the configuration and placement of slotted chamber assembly 70 provides for slots 74 to be entirely covered over the portion of slots closest to reservoir chamber 84, but provides for slots 74 to be uncovered or open over the portion of slots nearest barrier plate assembly 100, and particularly over that portion of the slots 74 opposite and immediately downstream of slot intercept passages 76.
Associated with supply gallery assembly 60 and attached thereto via tapered spacing supports 102 is spaced barrier plate assembly 100, comprising a rigid plate 104 having an edge which is positioned to be just outside the path of the high velocity stream as the stream leaves the confines of slot 74 and exits from the end of chamber assembly 70, and crosses the plane defined by plate 104. To ensure rigidity of plate 104, elongate backing plate 103 is securely attached to the inside surface of plate 104, via screws 105 positioned along the length of plate 104. Screws 106, which thread into threaded holes in spacing supports 102, are used to fix the position of plate 104 following alignment adjustment via threaded alignment bolts 108. Bolts 108 are associated with alignment guide 110 which is, at the time of machine set up, attached to the base of supply gallery assembly 60 via screws 112. By turning bolts 108, precise and reproducible changes in the relative elevation of plate 104, and thereby the clearance between the distal or upstanding edge of plate 104 and the path of the high velocity fluid jet(s), may be made. After the plate 104 is brought into satisfactory alignment relative to slots 74, screws 106 may be tightened and alignment guide 110, with bolts 108, may be removed, thereby fixing the edge of plate 104 in proper relation to the base of slots 74.
FIGS. 6 and 7 depict a fluid jet(s) impacting the substrate 26 perpendicular to the plane of tangency to the surface of support roll 21 at the point of impact; in some cases, however, it may be advantageous to direct the fluid jet(s) at a small angle relative to such plane, in either direction (i.e., either into or along the direction of rotation of roll 21). Generally, such angles (hereinafter referred to as "inclination angles") are about twenty degrees or less, but may be more for some applications.
As depicted in FIG. 7, when no control fluid is flowing through conduit 136 and slot intercept passages 76, highly pressurized water from passages 64 fills high pressure reservoir chamber 84 and is ejected towards substrate 26, via slots 74, in the form of a high velocity stream which passes in close proximity to the distal or upstanding edge of barrier plate 104. The high velocity streams are formed as the high pressure water is forced through the passages formed by covered portions of slots 74; the streams retain substantially the same cross section as they travel along the uncovered portion of slots 74 between supply gallery assembly 60 and barrier plate 104, diverging only slightly as they leave the confines of the slots 74, pass the upstanding portion of barrier plate 104, and strike the substrate 26.
As depicted in FIGS. 7 and 8, when a "no treatment" signal is sent to a valve controlling the flow of control fluid in a given conduit 136, a relatively low pressure control fluid, e.g., air, is made to flow from the selected conduit 136 into the associated slot intercept passages 76 of a given slot 74, and the high velocity stream traveling along that slot is subjected to a force directed to the open side of the slot 74. Absent a counteracting force, this relatively slight pressure introduced by the control fluid causes the selected high velocity stream to leave the confines of the slot 74 and strike the barrier plate rather than the substrate, where its energy is dissipated, leaving the substrate untouched by the energetic stream. In a preferred embodiment of the apparatus, a separate electrically actuated air valve such as the Tomita Tom-Boy JC-300, manufactured by Tomita Co., Ltd., No. 18-16 1 Chome, Ohmorinaka, Ohta-ku, Tokyo, Japan, is associated with each control stream conduit. A valve actuating signal may be generated by conventional computer means, i.e., via an EPROM or from magnetic media, and routed to the respective valves, whereby the high velocity treatment streams may be selectively and intermittently actuated in accordance with supplied pattern data.
FIG. 9 is a section view taken through lines XVII-XVII of FIG. 8, and diagrammatically indicates the effects of control fluid flow in conduits 136. As indicated, low pressure control fluid is flowing in control stream conduits 136 identified as "A" and "C" while no control fluid is flowing in conduits 136 identified as "B" and "D". In conduits "A" and "C", the high velocity jets 120A and 120C, respectively, have been dislodged from the lateral walls of slots 74 and are being deflected on a trajectory which will terminate on the inner surface of barrier plate 104. In contrast, no control fluid is flowing in conduits 136 identified as "B" and "D"; as a consequence, the high velocity jets 120B and 120D, laterally defined by the walls of slots 74, are on a trajectory which will avoid the upstanding edge of barrier plate 104 and terminate on the surface of roll 21, or substrate 26 supported thereby.
Additional information relating to the operation of such a spraying apparatus, including more detailed description of patterning and control functions, can be found in coassigned U.S. Pat. No. 5,080,952, that issued on Jan. 14, 1992, which is incorporated by reference as if fully set forth herein.
Water jet patterns may also be produced by having a raised or embossed support plate or roll that is positioned behind the fabric and treated by an array of water jets. Because of the different surfaces behind the fabric, the pattern will be implemented in the fabric as disclosed by U.S. Pat. No. 4,995,151, which issued on Feb. 26, 1992, which is incorporated by reference as if fully set forth herein.
All of the above methods must use a stream, jet or sheet of water that has some moment of force in the plane of the fabric which will produce the desired filling shift in the patterned area. The range of water pressure is between 100 to 4,000 p.s.i.g. The water pressure necessary to produce the desired filling yarn shift is determined by the moment of force in the plane of the fabric, size of the water jet, and the time the water jet is in contact with the filling yarn.
Referring now to FIG. 10, the next step in the process is to take the patterned fabric 26 and have this patterned fabric processed by a calender mechanism that is generally indicated by numeral 201. The patterned fabric 26 is placed on supply roll 220 and an unpatterned fabric 226 is placed on supply roll 210. Both the patterned fabric 26 and unpatterned fabric 226 are fed into an upper calendering roll 230 and lower calendering roll 232. For good patterning, both the patterned fabric 26 and unpatterned fabric 226 should be ribbed since the surface of the upper calendering roll 230 is smooth as well as the surface of lower calendering roll 232. The moire pattern is made by placing these two layers of ribbed fabric 26 and 226 on top of each other so that the ribs of the upper unpatterned fabric 226 are slightly off-grain in relation to the lower patterned fabric 26. These true moire patterns are produced when the upper unpatterned fabric 226 is sandwiched with the lower patterned fabric 26 and passed through the calender rolls 230 and 232 at high pressure so that wherever the filling yarns cross a moire pattern is produced. The unpatterned fabric 226 may be the lower fabric with the patterned fabric 26 being the upper fabric with no consequential difference. A pressure of 300 to 10,000 pounds per linear inch of fabric between the upper calendering roll 230 and lower calendering roll 232 on the fabrics 26 and 226 causes the ribbed pattern of the patterned fabric 26 to be pressed into the unpatterned fabric 226 and visa-versa. Pressure requirements for producing moire depend on the speed of traverse, temperature, moisture, and types of calender rolls utilized. A typical range for temperature would be between 100 and 450 degrees Fahrenheit. A typical range for moisture would be between 30 and 100 percent relative humidity for natural fibers. Manmade fibers are typically unaffected by relative humidity. The speed of traverse is typically between 10 and 100 feet per minute.
Flattened areas in the ribs reflect more light and create a contrast to unflattened areas. The patterned fabric 26 and unpatterned fabric 226 are then received by take-up rolls 250 and 240, respectively. The crushed and uncrushed portions of either fabric 26 or fabric 226 causes a difference in light reflectance. This creates a wavy or watery effect in both fabrics 26 and 226, respectively. In this case, both fabrics 26 and 226 will have the same moire pattern but they will be mirror images. This technique is especially useful when geometric or floral patterns are used. If both fabrics 26, 226 are patterned, they would be very difficult to keep in register.
Beat repeat patterns may be introduced by having the pick count different in the two layers of fabric 26 and 226 sandwiched together. This may be accomplished by weaving two different pick counts. Another way to accomplish this is to place tension on one of the layers which will reduce the pick count slightly to produce a beating. "Beating" is defined as the pattern developed due to superimposed waves of different frequencies.
Some very beautiful fabrics are produced by creating the moire fabric and then printing the fabric with a colorant such as a dye or pigment. The fabric may, also, be printed first and then water jet patterned and then calendered under pressure to produce a different effect. It may also be water jet patterned, printed and then calendered to produce a novel fabric. Any type of fabric printing may be used including but not limited to rotary screen, flat bed, air brush or engraved roll.
Most fiber types will work with this invention including, but not limited to, polyester, polyamide, acetate, rayon, cotton, and so forth. This invention is not restricted to plain weaves but most woven fabrics will work including, but not limited to, dobby and jacquard woven fabrics. Woven fabrics have warp yarns extending in the warp direction and fill yarns extending in the fill direction. For best results it is the fill yarns that have a ribbed effect. Furthermore, this invention is not restricted to woven fabrics since a moire pattern can be applied to warp knit fabrics. Warp knit fabrics have wales which are a column of loops lying lengthwise in the fabric and correspond to the warp in woven fabrics. Also, warp knit fabrics have courses which are a row of loops or stitches running across a knit fabric corresponding to filing in woven fabrics.
Fabric 226 does not have to be unpatterned and may also be patterned with a different pattern than patterned fabric 26. Also, either fabric 26 or 226 may have a different pick count to produce a beating pattern.
Other methods of applying pressure include high pressure rotary presses and platen presses.
The following examples demonstrate, without intending to be limiting in any way, the method by which fabrics of the present invention have been generated.
EXAMPLE 1
An apparatus similar to that schematically depicted in FIG. 3 was used, in accordance with the following specifications.
Fabric: a faille fabric having a warp comprised of 130 ends/inch of 70 denier bright polyester continuous filament and a fill comprised of 8/1 spun polyester and a pick count of 35. The faille fabric has been woven, prepared, dyed and heatset and has a weight of 5.6 ounces per square yard. A photomicrograph of this fabric is shown by FIG. 11 at 1.1 magnification. This fabric was then patterned with diagonal lines
Nozzle diameter: 0.017 inches.
Fluid: water, at a pressure of 1,000 p.s.i.g.
Pattern gauge: 20 lines per inch.
Source of pattern data: EPROM, with appropriate associated electronics of conventional design.
Roll: solid, smooth aluminum, rotating at a circumference speed of 10 yards per minute in the same direction as warp yarns in fabric.
In this Example, the entire fabric surface was treated in a series of diagonal spaced lines. The yarns have been laterally displaced where the stream impacted the fabric. A photomicrograph of this treated fabric is shown by FIG. 12 at 1.1 magnification.
This patterned fabric was then sandwiched with an unpatterned piece of the same fabric and run through a BRIEM® calender at eight yards a minute with a temperature of three-hundred and eighty degrees Fahrenheit on the steel roll with a pressure of one ton per linear inch. BRIEM® calenders were formally manufactured by Ernest L. Frank Associates, Inc., 515 Madison Avenue, New York, N.Y. 10022, who is no longer in existence. Both pieces of fabric display the moire pattern shown by the photomicrograph of FIG. 13 at 1.1 magnification.
EXAMPLE 2
An apparatus similar to that schematically depicted in FIG. 3 was used, in accordance with the following specifications.
Fabric: a faille fabric, as described in Example 1, having a warp comprised of 130 ends/inch of 70 denier bright polyester continuous filament and a fill comprised of 8/1 spun polyester and a pick count of 35. The faille fabric has been woven, prepared, dyed and heatset and has a weight of 5.6 ounces per square yard. This fabric was then patterned with linear wavy lines.
Nozzle diameter: 0.017 inches.
Fluid: water, at a pressure of 1,000 p.s.i.g.
Pattern gauge: 20 lines per inch.
Source of pattern data: EPROM, with appropriate associated electronics of conventional design.
Roll: solid, smooth aluminum, rotating at a circumference speed of 10 yards per minute in the same direction as warp yarns in fabric.
In this Example, the entire fabric surface was treated in a series of linear wavy lines. The yarns have been laterally displaced where the stream impacted the fabric. A photomicrograph of this treated fabric is shown by FIG. 14 at 1.1 magnification.
This patterned fabric was then sandwiched with an unpatterned piece of the same fabric and run through a BRIEM® calender at eight yards a minute with a temperature of three-hundred and eighty degrees Fahrenheit on the steel roll with a pressure of one ton per linear inch. Both pieces of fabric display the moire pattern shown by the photomicrograph of FIG. 15 at 1.1 magnification.
EXAMPLE 3
An apparatus similar to that schematically depicted in FIG. 3 was used, in accordance with the following specifications.
Fabric: a faille fabric, as described in Example 1, having a warp comprised of 130 ends/inch of 70 denier bright polyester continuous filament and a fill comprised of 8/1 spun polyester and a pick count of 35. The faille fabric has been woven, prepared, dyed and heatset and has a weight of 5.6 ounces per square yard. This fabric was then patterned with a floral pattern.
Nozzle diameter: 0.017 inches.
Fluid: water, at a pressure of 1000 p.s.i.g.
Pattern gauge: 20 lines per inch.
Source of pattern data: EPROM, with appropriate associated electronics of conventional design.
Roll: solid, smooth aluminum, rotating at a circumference speed of 10 yards per minute in the same direction as warp yarns in fabric.
In this Example, the entire fabric surface was treated in a floral pattern. The yarns have been laterally displaced where the stream impacted the fabric. A photomicrograph of this treated fabric is shown by FIG. 16 at 1.1 magnification. This patterned fabric was then sandwiched with another patterned piece of the same fabric and run through a BRIEM® calender at eight yards a minute with a temperature of three-hundred and eighty degrees Fahrenheit on the steel roll with a pressure of one ton per linear inch. Both pieces of fabric display the moire pattern shown by the photomicrograph of FIG. 17 at 1.1 magnification.
As this invention may be embodied in several forms without departing from the spirit or essential character thereof, the embodiments presented herein are intended to be illustrative and not descriptive. The scope of the invention is intended to be defined by the following appended claims, rather than any descriptive matter hereinabove, and all embodiments of the invention which fall within the meaning and range of equivalency of such claims are, therefore, intended to be embraced by such claims. | An apparatus and method for creation of moire fabric. This can be achieved by placing a first piece of fabric against a support member and directing at least one stream of fluid at the surface of said first piece of fabric to provide lateral yarn displacement. Then delivering said stream at a peak dynamic pressure in excess of about 300 p.s.i.g. and less than 4,000 p.s.i.g. and selectively interrupting and re-establishing contact between said stream and said surface in accordance with pattern information in order to pattern said first piece of fabric. This is followed by combining said patterned first piece of fabric with an unpatterned second piece of fabric in overlapping relationship and applying pressure by means of calender rolls having smooth surfaces to said combination of said first piece of patterned fabric and said second piece of unpatterned fabric. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application No. 61/809,934 filed on Apr. 9, 2013.
BACKGROUND OF THE INVENTION
[0002] This invention concerns rain gutters installed beneath roof eaves to collect rainwater runoff. The roof eaves sometimes form inside corners where roof sections pitched in different directions intersect, which requires an inside corner piece connected to straight gutter sections along each of the eaves forming the inside corner. A problem is created by an increased volume of rainwater runoff collected by a roof valley formed between the different roof sections. Since the increased flow volume directed into the inside corner piece causes overflow of rainwater over the top portion of the inside corner piece if it is not big enough to contain this increased volume.
[0003] Various solutions have been proposed to eliminate such overflows such as diverter baffles and rain water distributors, as shown in U.S. Pat. Nos. 2,899,912; 2,120,395 and 7,765,743; and patent publication nos. US 2002/0124476; US 2001/0017008; US 2002/0124476; and US 2002/0152691.
[0004] Such baffles and diverters are relatively expensive and add to the labor of installing a gutter system, and also often do not work well.
[0005] Another solution which has been proposed is to increase the capacity of the corner piece by providing a front wall extending across the inside corner at a 45 degree angle which widens the corner piece, as shown in U.S. Pat. Nos. 6,883,760; 2,537,243 and 2,120,395. The inside corner pieces described in the latter two patents are adapted to a simple semicircular gutter configuration formerly used.
[0006] In practice it has heretofore been too expensive to manufacture such 45° inside corner pieces matched to the standard curved and stepped shape of the front wall of roof gutters currently used and have not gained widespread commercial acceptance.
[0007] It is an object of the present invention to provide such an increased capacity corner piece and method of manufacture which can be made at a low enough cost to be commercially viable.
SUMMARY OF THE INVENTION
[0008] The above recited object of the invention and other objects which will be understood upon a reading of the follow specification and claims are achieved by an inside corner rain gutter piece having a curved and stepped front wall extending at 45° and configured to match the curved stepped shape of the front wall now in widespread use. Two similarly shaped wing sections are provided, one on each side of a front wall main section, the wing sections angled out from the front wall main section.
[0009] A flat bottom panel extends back from the bottom side of the front wall to a pair of right angled upright walls each formed up from a side of the bottom panel and integral therewith.
[0010] Preferably, a back wall extension piece is attached to short upright back walls to be substantially of the same height as the back wall of a standard gutter section while facilitating manufacture of the inside corner piece.
[0011] A pair of straight gutter section each have an end received within a respective one of the pair of angled out wing sections of the front wall and are cut off to angle their ends, so as to have a bottom wall angled out to completely overlie the inside corner piece bottom panel and to be positioned against a respective back wall of the corner piece thereof to complete the connection of the straight gutter sections to the inside corner piece.
DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a plan view of an inside corner formed by two intersecting roof eaves with a rain gutter inside corner piece according to the invention installed at the inside corner and the ends of two straight rain gutter sections connected thereto.
[0013] FIG. 2 is a pictorial view from the front of an inside corner piece for a rain gutter according to the invention.
[0014] FIG. 3 is a pictorial view from the rear of the inside corner piece for a rain gutter shown in FIG. 2 .
[0015] FIG. 4 is a plan view of the inside corner piece shown in FIGS. 2 and 3 .
[0016] FIG. 5 is a side view from the right of the inside corner piece shown in FIGS. 1-4 .
[0017] FIG. 6 is a plan view of the initial steps in making an inside corner piece for rain gutters according to the invention including cutting a blank from sheet aluminum.
[0018] FIG. 6A is an enlarged view of the blank cut out in the initial forming step with scrape areas shown covered with horizontal broken lines.
[0019] FIG. 7 is a pictorial view of a next intermediate step in making the inside corner piece according to the invention.
[0020] FIG. 8 is a pictorial view of a next intermediate step in making an inside corner piece according to the invention.
[0021] FIG. 9 is a pictorial view of a next intermediate step in making an inside corner piece according to the invention.
[0022] FIG. 10 is a pictorial view of a next intermediate step in making an inside corner piece according to the invention.
[0023] FIG. 11 is an inverted pictorial view of a completed corner piece according to the invention.
[0024] FIG. 12 is a pictorial view of an inverted partially completed inside corner piece according to the invention.
[0025] FIG. 13 shows additional forming of the top portion of a front wall of an inside corner piece according to the invention.
[0026] FIGS. 14A-14C are pictorial views of several variations in the configuration of the top portion of the front wall of an inside corner piece according to the invention.
[0027] FIG. 15 is a pictorial exploded view of an inside corner piece according to the invention with a fragmentary view of mating angled ends of straight gutter sections.
[0028] FIG. 16 is a pictorial view of the inside corner piece shown in FIG. 15 with the ends of straight gutter sections shown fit into respective sides of an inside corner piece according to the invention.
[0029] FIG. 16A is an enlarged front view of a corner piece according to the invention with fragmentary end portions of straight rain gutter sections installed therein.
[0030] FIG. 17 is a view of the section taken in FIG. 16 .
[0031] FIG. 18 is an enlarged plan view of an inside corner piece shown in FIGS. 15 and 16 with straight gutter sections ends being inserted into respective sides of an the inside corner piece according to the invention.
DETAILED DESCRIPTION
[0032] In the following detailed description, certain specific terminology will be employed for the sake of clarity and a particular embodiment described in accordance with the requirements of 35 USC 112, but it is to be understood that the same is not intended to be limiting and should not be so construed inasmuch as the invention is capable of taking many forms and variations within the scope of the appended claims.
[0033] Referring to the drawings and particularly FIGS. 1-5 , an inside corner piece 10 according to the invention is shown installed at an inside corner 12 formed by the intersection of two roof sections 14 , 16 which are pitched in different directions so as to form a valley 18 . The valley 18 descends to the inside corner piece 10 so that rain water collected in the valley runs off into the inside corner piece 10 .
[0034] The inside corner piece 10 includes an upright front wall 20 having a main section 22 extending at about a 45° angle to a pair of upright rear wall section 24 A, 24 B extending at right angles to each other. A pair of wing sections 26 A, 26 B are angled out from the main front wall section 22 so that each of these extend parallel to a respective rear wall section 24 A, 24 B.
[0035] A flat bottom panel 28 joins the front wall main section 22 to the rear walls 24 A, 24 B to form the completed inside corner piece 10 .
[0036] The wing sections 26 A, 26 B project out from respective ends of the main section 22 of the front wall 20 and beyond the sides 25 of the bottom panel 28 which each extend from a respective end of the front wall main section 22 .
[0037] The front wall main section 22 and wing sections 26 A, 26 B each have a curved stepped shape in general conformity to the shape of the outer wall of gutters currently being installed. That is, a short vertical section 30 extends up from the bottom, with an integral formed sinuously curved intermediate section 32 extending up and out to a top portion 34 thereof.
[0038] The front wall main section 22 may have a top portion 34 which projects straight up as seen in FIGS. 2 and 3
[0039] Each of the wing sections 26 A, 26 B is shaped in the same way, with a short vertical section 25 A, 25 B and stepped curved sections 27 A, 27 B.
[0040] The top portion 36 A, 36 B or each of the wing sections 26 A, 26 B comprises a short vertical section 38 A, 38 B, a horizontal section 40 A, 40 B extending back towards a respective rear wall 24 A or 24 B and a short downwardly extending terminal edge 42 A, 42 B. This is the same shape as conventional gutter top portions only slightly larger so as to be able to slidably receive the ends of lengths of straight gutter sections, as described further below.
[0041] The rear walls 24 A, 24 B are comprised of short upturned sides 34 A, 34 B integral with the bottom panel 28 and an extension piece 46 formed with two integrally connected sides 46 A, 46 B extended at a right angle to each other, and staked or riveted at 47 to a respective formed up rear wall side 34 A, 34 B to extend the rear walls 24 A, 24 B to the full height of a conventional rain gutter.
[0042] The reasons for such a two piece construction is related to the cost of manufacture of the inside corner piece 10 as described in detail herein below.
[0043] Referring to FIGS. 6-13C , the manufacturing steps comprise cutting and forming operations preferably in a conventional progressive die set up.
[0044] Sheet aluminum 48 is advanced from a roll of a width sufficient to allow a blank 50 to be cut therefrom (not shown) in a first step.
[0045] The blank 50 has two narrow strip areas 52 , 54 on the leading and trailing sides of the blank 50 respectively, projecting from a region 56 from which will be formed the bottom panel 28 of the inside corner piece 10 ( FIG. 6A ).
[0046] A second strip of aluminum sheet 58 is fed off a roll (not shown) in a next step so as to underlie the trailing strip 54 .
[0047] The width of the strip aluminum 58 corresponds to the finished height of the rear walls 24 A, 24 B.
[0048] In the next step indicated in FIG. 7 , the strip 58 is cut off to length to form a rear wall extension piece 59 , on end thereof staked or riveted to the underside of strip 54 .
[0049] Simultaneously a front piece 60 of the blank 50 is formed into the curved stepped shape of the front wall 20 . The wing sections 26 A, 26 Bs are formed from the subregions 62 , 64 of the blank 50 . The front wall 20 is also bent down along line 66 between regions 56 and 60 of the blank 50 .
[0050] In the next step, the trailing strip 54 and attached extension piece 59 is formed down 90° as seen in FIG. 8 .
[0051] The projecting end 68 of the strip 54 is formed back 90° under the leading strip 52 aligned with one end 45 of the strip 54 , as shown in phantom lines in FIGS. 8 and 9 .
[0052] The leading strip 52 is then formed down and staked to the end 68 of extension piece 59 , thus forming the back walls 24 A, 24 B ( FIGS. 10 and 11 ).
[0053] Referring again to FIG. 6A , the blank 50 area 60 has a trapezoidal shape with a pair of sides A, B each sloping from the ends of an upper side C out to a longer lower side D (which constitutes fold line 26 ).
[0054] This inclines the sides of parallelogram shaped areas 62 , 64 . When the area 60 is being shaped in the curved stepped shape it is folded up along 66 D line 1 to be inclined up from the area 56 (forming the bottom panel 28 ), the areas 62 , 64 are simultaneously also folded up when being shaped in the same way. Area 60 becomes the main section 22 of the front wall 20 . The areas 62 , 64 at the same time are folded out in relation to the folded up area 60 to be parallel to fold lines F, G. This forms the wing sections 20 A, 20 B of the front wall 12 .
[0055] The shape and position of areas 62 , 64 causes the top edges H, Ito be moved to be parallel to the top edge C of the area 60 , and the bottom edges J, K to be parallel to the back walls 24 A, 24 B respectively.
[0056] This results in the formed top portions 36 A, 36 B of the wing sections 26 A, 26 B to be aligned with the top portions and curved stepped front of the straight gutter sections 68 , 70 ( FIG. 15 ) to allow them to be inserted into the inside corner side piece 10 as shown in FIGS. 16 and 18 .
[0057] The front wall main section 22 extends at about 45° to the back walls 24 A, 24 B and also to the installed straight gutter sections 68 , 70 .
[0058] This relationship creates an enlarged volume capacity of the inside corner piece 10 better able to contain the increased volume of rainwater runoff from the roof valley 18 ( FIG. 1 ).
[0059] In order to minimize excessive scrap, lateral projections from the blank 50 are minimized, as can be seen in FIG. 6A where the areas of trimming scrap are indicated by horizontally broken lines. This is done here by minimizing both the length and the height of the short back walls 34 A, 34 B directly formed by the strips 52 , 54 of the blank 50 . The width of the blank is reduced by first forming the short walls 34 A, 34 B and then attaching the separate back wall extension 46 A, 46 B to complete the back walls 24 A, 24 B. The length of the back walls is reduced by angling the floor panel sides L, M back towards each other rather than at 90° to the wing section 26 A, 26 B as seen in FIG. 6A .
[0060] This necessitates cutting mating ends of the mated straight gutter sections 68 , 70 at an angle as shown in FIGS. 15 , 16 and 18 .
[0061] The formed wing sections 26 A, 26 B slidably receive the shaped side of the straight sections 68 , 70 which are advanced therein to the end of the respective wing section 26 A, 26 B. The straight section ends cannot be further advanced therein as they would create flow obstructions within the inside corner piece 10 .
[0062] Since the length of the rear walls 24 A, 24 B does not extend out to be even with the end of the wing sections 26 A, 26 B, the straight sections must be cut along an angle of about 45° to overlap the bottom panel 28 and rear walls 24 A, 24 B as shown in FIGS. 15 , 16 and 18 .
[0063] FIG. 11 shows the front wall 20 with the (inverted) top portion 34 , 36 A, 36 B of the main section 20 and wing sections 26 A, 26 B yet to be formed. The forming of the portion can be done in a variety of ways, such as shown in FIGS. 2 , 3 and 13 in which the main section top portion 24 is left straight up and the tops of the wing sections 36 A, 36 B formed over to match the mating gutter straight sections, but a little larger in size to slidably receive the same therein.
[0064] FIGS. 14A , 14 B, 14 C show other possible variations with FIG. 14A showing the main section top portion 34 A formed over in a fashion similar to the top portions 36 A, 36 B of angled wing sections 26 A, 26 B.
[0065] The slits 72 formed into the blank 50 ( FIG. 6A ) accommodate the separate forming of the top portions 36 A, 36 B, 34 A.
[0066] FIG. 14B shows the main section top portion 34 B formed straight out with formed over wing section tops.
[0067] FIG. 14C shows the main section top portion 34 left straight up and wing section top portions 36 C and 36 D formed straight out.
[0068] FIGS. 15-18 show the connection of a inside corner piece 10 according to the invention to the two straight gutter sections 68 and 70 which would extend along the two roof eaves forming an inside corner.
[0069] The straight gutter sections 68 , 70 mate with an end of the inside corner piece 10 by the ends 78 A, 78 B sliding within a respective wing sections 26 A, 26 B and the rear walls 80 , 82 thereof within the rear walls 24 A, 24 B ( FIG. 18 ).
[0070] Since the wing sections 26 A, 26 B each extend substantially further out towards the respective straight sections 68 , 70 than the rear walls 24 A, 24 B, the straight sections 68 , 70 must be cut off at angle. If their ends were squared off, the ends would need to extend well into the inside corner piece 10 past the corners 74 , 76 ( FIG. 13 ) which the wings 26 A, 26 B make with the main section 22 of the front wall 20 . This would create turbulence and flow resistance with water flow out of the two ends of the inside corner piece 10 and likely create leaks.
[0071] Accordingly, the ends 78 A, 78 B of the straight sections 68 , 70 are cut at an angle to locate the outer wall of each at the respective corners 74 , 76 while each of the back walls 80 , 82 thereof extend well past the ends of the back walls 24 B, 24 A as indicated in FIGS. 15-18 creating sufficient overlap to enable a sealed connected to be made.
[0072] Accordingly, the inside corner piece 10 can be made cheaply by conventional dies and minimal scrap to be commercially practical, thereby satisfying a long felt need in the industry. | An inside corner piece for a rainwater gutter system having an angled front wall extending at a 45 degree angle to increase the amount of water able to be collected by the corner piece, with each end of a main section of the front wall having an angled out wing section slidably receiving an end of one of the straight gutter sections. The manufacturing method minimizes scrap by the shape of a blank used to form the corner piece | 4 |
BACKGROUND OF THE INVENTION
This invention relates to automatic shoe clearance adjusting devices in shoe drum brakes for use in vehicles such as automobiles or the like.
Automatic shoe clearance adjusting devices are generally mounted in shoe drum brakes for adjusting the clearance between the shoe and the drum to a desired value automatically when the clearance has increased according to wear of shoe lining.
One prior art automatic shoe clearance adjusting device comprises a strut of adjustable length including a first strut member having a hollow portion for slidably receiving a male thread portion of a second strut member, an adjust nut having ratchet teeth on the outer periphery thereof and engaging with the male thread portion of the second strut member with one side surface of the adjust nut abutting with an open end of the hollow portion of the first strut member. An adjust lever is pivotally connected to one end of the strut (one end of either of the first and second strut members) and is pivotable in response to the actuation of a hand brake lever so as to engage with the adjust nut to rotate it when shoe clearance exceeds a predetermined value, thereby maintaining a suitable shoe clearance by rotating the adjust nut relative to the second strut member.
In the aforementioned prior art shoe clearance adjusting device, it is necessary to arrange the adjust lever such that the adjust lever can escape from the adjust nut when the adjust lever returns to its original position after rotating the adjust nut (in a direction increasing the effective length of the strut) to prevent the reverse rotation of the adjust nut, and that the adjust lever can escape from the movement of the hand brake lever (having some amount of free movement relative to the hand brake lever) so as to permit the actuation of the hand brake lever even when the adjust lever cannot rotate because of rust or the like.
It has been proposed to mount the adjust lever pivotally on the hand brake lever with a coil spring acting therebetween so that the adjust lever is urged against the adjust nut by the compressive force of the coil spring and is urged in the direction of rotational movement of the hand brake lever by the torsional force of the coil spring. The adjust lever can escape in respective opposite directions when the coil spring deflects in respective opposite directions.
In the heretofore proposed devices, the torsional force of the coil spring acts to cause excessive frictional force between the adjust lever and the hand brake lever when the adjust lever escapes from the adjust nut against the compressive force of the coil spring, which tends to cause insufficient escape movement of the adjust lever from the adjust nut, thereby resulting reverse rotation of the adjust nut.
Further, in the heretofore proposed devices, the coil spring does not necessarily contact at a predetermined position relative to the adjust lever for transmitting compressive force. Thus, it has been difficult to obtain a stable urging force acting on the adjust nut. Further, parallelism between the hand brake lever and the adjust lever will sometimes be impaired by the compressive force of the coil spring and clearance adjustment will not be performed.
An object of the present invention is to remove the shortcomings of the prior art automatic shoe clearance adjusting device of the aforementioned type by a special construction of the adjust lever and coil spring arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
Various embodiments of the present invention are shown in accompanying drawings in which:
FIG. 1 is a front view of a shoe drum brake incorporating an automatic shoe clearance adjusting device according to the invention.
FIG. 2 is a partially sectional enlarged view of the automatic shoe clearance adjusting device in FIG. 1.
FIG. 3 is an enlarged cross sectional view taken along line III--III in FIG. 1 to show a side view of the device of FIG. 2, wherein the back plate is omitted.
FIG. 4 is an enlarged view of the adjust lever shown in FIG. 2.
FIG. 5 is a side view of the adjust lever of FIG. 4.
FIG. 6 is an enlarged cross-sectional partial view showing the relation between the hand brake lever, the adjust lever, the supporting shaft and the coil spring of FIG. 2.
FIG. 7 is a side view as viewed along line VII--VII in FIG. 6.
FIG. 8 is an enlarged perspective view of the adjust lever and the coil spring assembled in position in the shoe drum brake of FIG. 1.
FIG. 9 is a view taken generally along line IX--IX in FIG. 6, but with the adjust lever shown in a modified form.
FIG. 10 is a view similar to FIG. 9 but showing a further modified form.
FIG. 11 is a view similar to FIG. 3, wherein the hand brake lever is replaced by an adjust lever mounting member.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, the reference numeral 1 denotes a brake drum secured to a wheel (not shown) for rotation therewith. Shoes 2 and 3 having respectively linings 4 and 5 bonded on respective surfaces thereof are disposed inside of the drum 1. One end of each of the shoes 2 and 3 is supported on an anchor 8, and the other ends of the shoes 2 and 3 abut respectively with the opposite ends 10 and 11 of a brake cylinder 9. Two springs 12 and 13 extend respectively between the shoes 2 and 3 for urging the shoes toward each other. The brake cylinder 9 and the anchor 8 are secured on a stationary back plate 14.
As shown clearly in FIGS. 2 and 3, a hand brake lever 15 having a tip end 15a engaging with a cut-out portion 7a of web 7 of the shoe 3 is provided for manually applying the brake, and acts between the shoes 3 and 2 through a strut 16. A first strut member 17 of the strut 16 has a fork portion 18 for engaging with a cut-out portion 6a of web 6 of the shoe 2. The first strut member 17 has a hollow portion for slidably receiving male thread portion 20 of a second strut member 19. The male thread portion 20 threadingly engages with an adjust nut 21 which has ratchet teeth on the outer circumference thereof. One of the side surfaces of the adjust nut 21 abuts with the open end of the hollow portion of the first strut member 17. The second strut member 19 is pivotally mounted to the hand brake lever 15 through a supporting shaft 22 which is secured to the hand brake lever 15. An adjust lever 23 is pivotally mounted on the supporting shaft 22, and the tip end 23a thereof acts as a pawl for cooperating with the ratchet teeth of the adjust nut 21.
As shown in FIGS. 4 and 5, the adjust lever 23 has transverse projections 23c and a generally L-shaped detent 23d. The detent 23d defines a projection 23g projecting oppositely relative to the projections 23c. Further, a recessed portion 23e is formed in the upper side portion of the end portion 23b as shown in FIG. 5 for locating one end of a spring 24. The recessed portion 23e and the detent 23d of the adjust lever 23 are disposed at positions at substantially the same radial distance from the center 0 of the pivotal movement of the lever 23, or at the axis of the supporting shaft 22.
The spring 24 acts as both a compression and a torsion spring and surrounds the supporting shaft 22. One end of spring 24 abuts with the recessed portion 23e as mentioned above, and the other end of spring 24 engages with a groove 22b (FIG. 3) formed in a flanged portion 22a secured to or formed on the lower end of the shaft 22 as shown in FIG. 2. Thus, the lever 23 receives torsional force turning the lever 23 around the center 0 in the counterclockwise direction in FIGS. 3 and 5 (the direction of arrow B). Further, the spring 24 abuts with the projecting portion 23g of the lever 23 and a side surface of the flanged portion 22a as most clearly shown in FIGS. 9 or 10 for transmitting compressive force to the lever 23 which urges the adjusting lever in the direction of arrow A in FIG. 2 around a fulcrum defined by the projections 23c.
The detent 23d of the lever 23 is received in a cut-out portion formed in the hand brake lever and one side surface 15b of the cut-out portion abuts normally with one side surface of the detent 23d so as to act as a stopper which receives torsional force of the spring 24 transmitted through the recessed portion 23e.
In applying the hand brake, the hand brake lever 15 is rotated in the direction of arrow C in FIG. 3. The brake shoes 2 and 3 are expanded by the hand brake lever 15 and the strut 16. The adjust lever 23 follows the movement of the hand brake lever 15 and rotates in the same direction receiving the torsional force of the spring 24. When wear in the lining 4 or 5 is excessive, the adjust nut 21 is rotated. When hand brake is released, the adjust lever 23 moves in the direction of arrow D in FIG. 2 against the compressive force of the spring 24 around the fulcrum defined by the projections 23c abutting with the adjacent side surface of the hand brake lever 15 so that the pawl 23d of the adjust lever 23 will ride over one or more teeth of the ratchet teeth of the adjust nut 21 without rotating the adjust nut in the reverse direction. When the adjust nut 21 is rotated, the second strut member 19 will be moved out from the first strut member 17 to compensate for the wear of the lining 4 or 5.
As heretofore described, it is necessary that the adjust lever 23 acts reliably to rotate the adjust nut 21 in applying hand brake and to move away from the adjust nut 21 in releasing hand brake for preventing reverse rotation of the adjust nut 21. These requirements can be attained by reducing the frictional force between the adjust lever 23 and the supporting shaft 22 and/or the hand brake lever 15 to thereby afford smooth movement of the adjust lever 23 in the direction of arrows A and D in FIG. 2, and to reduce the compressive force of the spring 24. The reduced frictional force assures smooth movement of the pawl 23a of the adjust lever 23 in both directions approaching toward and retracting from the adjust nut 21 while receiving relatively small compressive force from the spring 24, thereby obtaining reliable engagement between the pawl 23a and the ratchet teeth and also smooth riding over movement of the pawl retracting from the ratchet teeth.
Further, it is necessary to remove excessive play between the adjust lever 23 and the hand brake lever 15 in the rotational direction for improving the adjusting characteristics of the device.
According to one of the features of the present invention, the projections 23c of the adjusting lever 23 (which act as a fulcrum during movement of the lever in the directions of the arrows A and D), the recessed portion 23e (that point on which the torsional force of the spring 24 acts) and the detent 23d (that point from which the torsional force of the spring 24 is received by the hand brake lever 15) are disposed adjacent with each other. Thus, unnecessary frictional force will not be caused by the torsional force of the spring 24, which will be described hereinafter in detail.
Assuming that the torsional force of previous spring 24' is transmitted to the adjust lever at a point 23e" in FIG. 7 and is transmitted from the adjust lever to the hand brake lever at a point 23d" in FIGS. 6 and 7, thus, when the adjust lever 23 moves around the fulcrum 23c in the directions of arrows A and D substantial frictional force will occur between a detent 23d' and the hand brake lever, according to the torsional force of a spring 24'. However, according to the present invention, the detent 23d and the projections 23c are disposed adjacent to each other, and the relative frictional movement between the detent 23d of the adjust lever 23 and the stopper 15b of the hand brake lever when the adjust lever 23 pivotally moves in the direction of arrow D will become minimum.
Further, assuming that the torsional force of the spring 24' acts on the point 23e" in FIG. 7 the adjust lever 23 will receive a moment turning the lever 23 in the direction of arrow E in FIG. 7 around the point 23d", and a portion of the opening 23f will be urged against the supporting shaft 22 which will cause substantial frictional force when the lever 23 pivotally moves in the direction of arrow D in FIG. 6. However, according to the present invention, the torsional force of the spring 24 acting on the point 23e will be transmitted to the hand brake lever 15 through the detent 23d. Thus, any such moment will not act on the adjust lever 23 and a suitable clearance can be maintained between the opening 23f and the supporting shaft 22 over the entire periphery thereof.
Further, it is possible to improve the adjusting characteristics of the device since the clearance between the opening 23f and the supporting shaft 22 can be minimized without increasing frictional resistance therebetween.
In the illustrated embodiment, the shoe clearance adjusting function is performed when the hand brake lever is actuated, but it will be noted that the present invention may be applicable to a shoe drum brake of the type in which the automatic adjustment function is performed when the brake is actuated hydraulically. In FIG. 11, the hand brake lever is modified to form an adjust lever mounting member 15' by omitting the lever portion 15c, the tip end portion 15'a of the member 15' is inserted into an opening 7a formed in the web 7 of the shoe 3, and the other end portion of the member 15' is rotatably and slidably supported on the back plate 14. The supporting shaft 22 is urged toward the shoe 2 by suitable spring means 31. Thus, the lever 15 and the adjust lever 23 are rotated when the shoes 2 and 3 are separated by actuating wheel cylinder 9, and excessive clearance between the drum and shoe linings is automatically adjusted upon applying the foot brake.
Further, the adjust nut 21 is rotated during the separating stroke of the shoes 2 and 3 in the illustrated embodiments, but it is possible to arrange such that the adjustment is effected during the releasing stroke of the shoes 2 and 3, by disposing the direction of the pawl 23a of the adjust lever 23 and the ratchet teeth of the nut 21 oppositely, and the direction of the torsional force of the spring 24 oppositely.
The projecting portion 23g of the adjust lever 23 acts to determine the point through which compressive force of the spring 24 is transmitted to the lever 23. Thus, the lever 23 receives a substantially constant moment around the fulcrum 23c in the direction of arrow A. Further, in the the projecting portion 23g is located between the projections 23c of the lever 23 as viewed in FIG. 5, thus, any undesirable turning moment around the lengthwise axis of the adjust lever 23 will not occur.
In a modified form shown in FIG. 9 a projecting portion 24a is formed in the coil spring 24 for abutting with a generally flat side surface of the adjust lever 23 for defining an abutting portion 23'g. | An automatic shoe clearance adjusting device in a shoe drum brake includes a strut of adjustable length having an adjust nut with ratchet teeth on the outer periphery thereof, an adjust lever having a pawl at one end thereof for cooperating the ratchet teeth, and a coil spring acting on the adjust lever for moving the pawl of the lever circumferentially and radially relative to the adjust nut by torsional and compressive forces respectively. A point through which the torsional force is transmitted to the lever, a point through which the torsional force is received by another member normally, and a fulcrum point around which the layer pivots in the radial direction are arranged such that these three points are adjacent to each other. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit of priority under 35 USC §119 to Japanese Patent Application No. 2004-8042, filed on Jan. 15, 2004, the contents of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a semiconductor device and it is directed to an insulating gate type bipolar transistor suitable for use as a power supply switching element, for example.
[0004] 2. Related Background Art
[0005] In the field of power semiconductor devices, there is a strong request for low on-voltage and reduction of turn-off loss in addition to enhancement of resistance to high breakdown voltage and availability for larger current. To meet these requirements, IEGT (Injected Enhanced Gate Transistor) has been developed as a further improvement of IGBT (Insulated Gate Bipolar Transistor).
[0006] The IEGT is a powering semiconductor device that has realized low on-resistance by rendering the emitter side of an n-type base layer have the peak of carrier concentration rendering it accumulate holes to enhance the efficiency of electron injection from the emitter electrode at the time of turning on.
[0007] FIG. 11 is a cross-sectional diagram showing an example of a trench-structured vertical IEGT by a related art. In the IEGT 90 shown here, a p-type collector layer 114 formed on one side of an n-type drift layer (n-type base layer in this example) 100 via an n-type buffer layer 112 . On the opposite side of the n-type drift layer 100 , a p-type impurity diffusion layer is formed, and a plurality of trenches TR are formed to penetrate the p-type impurity diffusion layer from its surface and reach an inner region of the n-type drift layer 100 . Thus, the p-type impurity diffusion layer is divided to main cell regions MC and dummy cell regions DC that are used as p-type main base layers 116 and p-type dummy base layers 118 , respectively.
[0008] In the surface layer of each p-type main base layer 116 of the main cell region MC, n-type emitter layers 124 are formed selectively. The surface of each p-type dummy base layer 118 of the dummy cell region DC is covered by an insulating film 132 to keep the potential of the p-type dummy base layer 118 floating.
[0009] A collector electrode 126 is formed on the p-type collector layer 114 . An emitter electrode 128 is formed over the p-type main base layer 116 and the n-type emitter layers 124 , and it is connected to the n-type emitter layer 124 . In each trench TR, a gate electrode 122 is buried via a gate insulating film 120 . As a result of the explained structure, an n-type channel MOSFET for electron injection using the p-type main base layer 116 as a channel region and selectively connecting the n-type emitter layers 124 to the n-type drift layer 100 is formed in each main cell region MC.
[0010] In the IEGT 90 shown in FIG. 11 , the drift layer 100 of the main cell region MC has the carrier concentration profile having the peak on the part of the emitter electrode 128 . Therefore, a sufficiently narrow current path is formed, which connects the n-type drift layer 100 and the emitter electrode 128 . As a result, in the on-state of the IEGT 90 , the current path increases the resistance to the flow of holes moving from the n-type drift layer 100 toward the emitter electrode 128 through the p-type main base layer 116 of the main cell region MC, and hence limits the discharge of holes to the emitter electrode 128 . This results in enhancing the electron injection efficiency from the n-type emitter layer 124 to the n-type drift layer 100 , promoting the conductivity modulation of the n-type drift layer 100 , and attaining a low on-voltage.
[0011] The IEGT 90 shown in FIG. 11 , however, involves the problem that the gate voltage runs to overshoot due to so-called negative capacitance, and thereby becomes impossible to control the voltage change rate dV/dt during the on-time. This problem is explained below with reference to FIGS. 12 and 13 . In the attached figures, common and equivalent elements are labeled with common reference numerals, and their explanation will be repeated only when necessary.
[0012] FIG. 12 is a graph showing an example of voltage and current waveform at the on-time of the IEGT 90 shown in FIG. 11 . In this graph, V ge is a gate-emitter voltage, V ce is a collector-emitter voltage, and I c is a collector current.
[0013] In this experiment, the voltage of the IEGT was 1200 V, the voltage applied between the collector and the emitter was 600V, and the gate resistance R g was 51 Ω. Resistance between the p-type dummy base layer 118 and the emitter electrode 128 was 10 Ω.
[0014] As shown in FIG. 12 , the collector-emitter voltage change ratio (dV/dt) of the IEGT 90 shown in FIG. 11 was as large as 20 kV/μs or more in the initial stage of the mirror period t 1 ˜t 2 (the period for charging between the gate and the collector with the voltage applied between the gate and emitter), and the waveform vibrated seriously.
[0015] FIG. 13 is a graph showing an example of the gate charge characteristics during the on-time of the IEGT 90 shown in FIG. 11 , which was obtained by a simulation. In this graph, V ge is the gate-emitter voltage, V ce is the connector-emitter voltage, and Q g is the gate charge. Solid lines show characteristics obtained by dynamic calculation whereas broken lines show characteristics obtained by static calculation (V ce =0V and V ce =600V). Conditions of the IEGT in this simulation are equal to those explained in conjunction with FIG. 12 except the parameters of this simulation.
[0016] In the IEGT 90 shown in FIG. 11 , the gate-emitter voltage V ge (hereinbelow referred to as Vge(on) ) in the mirror period (the period t 1 -t 2 in FIG. 12 ) is contained in the V ge region where Q g decreases as V ge increases in the static characteristics of V=600V. In this case, the waveform of Q g significantly vibrates on the dynamic characteristics as shown in FIG. 13 .
[0017] The phenomenon of the decrease of Q g with the increase of V ge is called negative capacitance (negative capacitance of the gate) because C g =dQ g /dV ge becomes a negative value. The negative capacitance is known as being the cause of bringing about current unbalance upon parallel driving of a semiconductor device (see, for example, Japanese Patent Laid Open (kokai) 2000-40951 and IEEE Device Letters, vol. 18, pp 121-123.)
[0018] As seen in the dynamic characteristics of FIG. 13 , once the gate emitter voltage V ge (on) in the mirror period enters in the V ge region exhibiting the negative capacitance, the gate-emitter voltage V ge vibrates. This results in increasing the gate-emitter voltage V ge in a short time and permitting rapid electrical conduction of the collector current to invite a large dV/dt.
[0019] Through some researches, the Inventor has confirmed that the overshoot of the gate-emitter voltage V ge by such negative capacitance occurs because the potential of the p-type dummy base layer in the dummy cell region is not kept floating completely.
[0020] In greater detail, even when the device is designed to keep the potential of the p-type dummy base layer floating as explained before, if the potential in the off-time is fixed near the zero potential via a parasitic resistance caused by the parasitic structure (for example, partial connection to the cell end or the junction terminal end), after the device is turned on, immediately upon the rise of the gate-emitter voltage V ge (on) to the threshold voltage V th , holes injected thereby suddenly increase the potential of the p-type dummy base layer and ultimately bring about the overshoot of the gate-emitter voltage V ge .
[0021] On the other hand, if the emitter contact is formed over the entire surface of the dummy base layer, then the problem of uncontrollability of dV/dt will be overcome. In this case, however, the IE effect will be lost, and the low V ce (sat) characteristics cannot be realized.
[0022] To prevent this problem, the use of the structure described in Japanese Patent Laid Open (kokai) 2000-40951, for example, leads to realization of complete floating configuration of the dummy base layer while maintaining the IE effect.
[0023] However, in the structure described in Japanese Patent Laid Open (kokai) 2000-40951, if the cell length is changed, for example, when the current capacitance is different, then the structure must be changed as well accordingly. Therefore, the structure disclosed in Japanese Patent Laid Open (kokai) 2000-40951 involves the problem that it lacks compatibility or commonness as a unit structure.
BRIEF SUMMARY OF THE INVENTION
[0024] According to a first aspect of the present invention, there is provided a semiconductor device comprising:
a drift layer of a first conductivity type; a collector layer of a second conductivity type located on the drift layer; a collector electrode located on the collector layer; a base layer of the second conductivity type located in a region isolated from the collector layer on the drift layer; a plurality of trenches formed at certain intervals to extend from the top surface of the base layer into the drift layer and thereby divide the base layer to main cell regions and dummy cell regions; a first emitter layer of the first conductivity type selectively formed in the surface layer of the base layer in each main cell region to extend along adjacent one of the trenches; gate electrodes formed in the trenches sandwiching each main cell region among said plurality of trenches via a gate insulating film; an emitter electrode located over the base layer and the first emitter layer in each main cell region; and a second emitter layer of the first conductivity type selectively formed so as to be scattered in the surface layer of the base layer in each dummy region and having a surface area smaller than that of the first emitter layer.
[0034] According to a second aspect of the present invention, there is provided a semiconductor device comprising:
a drift layer of a first conductivity type; a collector layer of a second conductivity type located on the drift layer; a collector electrode located on the collector layer; a base layer of the second conductivity type located in a region isolated from the collector layer on the drift layer; a plurality of trenches formed at certain intervals to extend from the top surface of the base layer into the drift layer and thereby divide the base layer to main cell regions and dummy cell regions; a first emitter layer of the first conductivity type selectively formed in the surface layer of the base layer in each main cell region to extend along adjacent one of the trenches; gate electrodes formed in the trenches sandwiching each main cell region among said plurality of trenches via a gate insulating film; an emitter electrode located over the base layer and the first emitter layer in each main cell region; and a second emitter layer selectively formed in the surface layer of the base layer in each dummy cell region, wherein resistance value of a floating resistor as a resistance between the base layer of the dummy cell region and the emitter electrode is adjusted to be smaller than the resistance value causing rise of the gate-emitter voltage due to negative capacitance of the gate in a period to charge the gate and the collector by a voltage applied between the gate and the emitter when the device is turned on.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] In the accompanying drawings:
[0046] FIG. 1 is a plan view showing schematic configuration of a semiconductor device according to a first embodiment of the invention;
[0047] FIG. 2 is a cross-sectional view taken along the B-B line of FIG. 1 ;
[0048] FIG. 3 is a cross-sectional perspective view taken along the A-A cut line of FIG. 1 ;
[0049] FIG. 4 is a graph showing the voltage and the current waveforms at the turn-on time of the IEGT shown in FIG. 1 ;
[0050] FIG. 5 is a graph showing an example of gate charge characteristics appearing when the IEGT 1 is turned on, which are obtained by simulation;
[0051] FIG. 6A is a graph showing a relation of dV/dt and on-voltage relative to the resistance value R float of the floating resistor, which is obtained by simulation;
[0052] FIG. 6B is a graph showing a relation of the range NCR of V ge exhibiting negative capacitance and on-voltage relative to the resistance value R float of the floating resistor;
[0053] FIG. 7 is a plan view schematically showing the configuration of a semiconductor device according to a second embodiment of the invention;
[0054] FIG. 8 is a plan view schematically showing the configuration of a semiconductor device according to a third embodiment of the invention;
[0055] FIG. 9 is a plan view schematically showing the configuration of a semiconductor device according to a fourth embodiment of the invention;
[0056] FIG. 10 is a cross-sectional view schematically showing the configuration of a semiconductor device according to a fifth embodiment of the invention;
[0057] FIG. 11 is a cross-sectional diagram showing an example of a trench-structured vertical IEGT by a related art;
[0058] FIG. 12 is a graph showing an example of voltage and current waveform at the on-time of the IEGT shown in FIG. 11 ; and
[0059] FIG. 13 is a graph showing an example of the gate charge characteristics during the on-time of the IEGT shown in FIG. 11 , which was obtained by a simulation.
DETAILED DESCRIPTION OF THE INVENTION
[0060] Some embodiments of the invention will be explained below with reference to the drawings. In the explanation made below, the first conductivity type refers to the n-type and the second conductivity type refers to the p-type.
First Embodiment
[0061] FIG. 1 is a plan view showing schematic configuration of a semiconductor device according to the first embodiment of the invention. FIG. 2 is a cross-sectional view taken along the B-B line of FIG. 1 , and FIG. 3 is a cross-sectional perspective view taken along the A-A cut line of FIG. 1 .
[0062] As shown in the cross-sectional view of FIG. 2 , the IEGT 1 according to this embodiment includes an n-type drift layer (n-type base layer) 10 , n-type buffer layer 12 , p-type collector layer 14 , first p-type base layers 16 , second p-type base layers 18 , first emitter layers 24 , second emitter layers 32 , trenches TR, gate insulating films 20 , gate electrodes 22 , emitter electrodes 28 , via contacts 30 and collector electrode 26 .
[0063] The p-type collector layer 14 lies on one side of the n-type drift layer 10 via the n-type buffer layer 12 . On the other side of the n-type drift layer 10 , a p-type base layer ( 16 , 18 ) is formed. A plurality of trenches TR are formed at certain intervals so as to penetrate the p-type base layer from its surface and reach a region in the n-type drift layer 10 . Thus, main cell regions MC and dummy cell regions DC are defined in the surface region of the p-type base layer, and the p-type base layer is divided to the first base layer 16 and the second base layer 18 in each unit region. Instead of dividing the common p-type base layer by the trenches TR, it is also possible to form the first p-type base layer 16 and the second p-type base layer 18 as independent layers.
[0064] The first emitter layers 24 are selectively formed in the surface layer of each p-type base layer 16 . The emitter electrode 28 is located to locally contact the surfaces of the first emitter layers 24 opposed and the surface of the first base layer 16 between the opposed first emitter layers 24 in each main cell region MC.
[0065] The gate electrode 22 is formed in each trench TR so as to be covered by the gate insulating film 20 . The collector electrode 26 is located in contact with the collector layer 14 .
[0066] The second emitter layer 32 is one of unique features of the IEGT 1 according to this embodiment, and it is selectively formed in the surface layer of the second base layer 18 in a pattern of narrow isolated layers (see FIG. 1 ) in the dummy cell regions DC. In this embodiment, the second emitter layers 32 are formed to make an opposed pair in each dummy cell region DC, and respective ends of the second emitter layers 32 contact nearest trenches TR as also shown in the cross-sectional perspective view of FIG. 3 . The second emitter layers 32 make a current path for transferring holes to the emitter electrode 28 to an extent not affecting the electron injection efficiency from the emitter electrode 28 to the n-type drift layer 10 in the on-time of the device.
[0067] As also shown in FIG. 3 , each via contact 30 is located in contact with the surface regions of the second emitter layers 32 and the location of the second base layer 18 sandwiched by the second emitter layers 32 (emitter contact region Rec 2 ) is located so as to electrically connect the second base layer 18 to the emitter electrode 28 . The via contacts 30 and the emitter layers 32 form floating resistors 34 . Therefore, resistance value of each floating resistor 34 is adjusted by shapes or geometries of the emitter layer 32 and the via contact 30 .
[0068] FIG. 4 is a graph showing the voltage and the current waveforms at the turn-on time of the IEGT 1 according to this embodiment, which was obtained experimentally. In the IEGT 1 according to this embodiment, actually used in this experiment, resistance voltage was 1200 V, voltage applied to the collector and the emitter was 600 V, and the gate resistance Rg was 51 Ω.
[0069] As shown in FIG. 4 , in the IEGT 1 according to the instant embodiment, since the second base layer 18 is connected to the emitter electrode 28 via the via contact 30 , potential of the base layer 18 is not fixed to zero even in the off-time. A local channel region is then formed in the dummy cell region DC in the second base layer 18 under the second emitter regions when the device is turned on. Therefore, dV/dT at the initial stage of the mirror period t 1 -t 2 is reduced to approximate 5 kV/μs, and waveform vibration is suppressed as well. This is in contrast to the conventional IEGT in which the voltage change ratio (dV/dt) is approximate 20 kV/μs and the waveform vibrates violently (see FIG. 12 ).
[0070] FIG. 5 is a graph showing an example of gate charge characteristics appearing when the IEGT 1 is turned on, which were obtained by simulation. Conditions of IEGT used in the simulation were identical to those explained in conjunction with FIG. 4 except the parameters of this simulation.
[0071] In the IEGT 1 according to this embodiment, the region of V ge exhibiting the negative capacitance is shifted to the high-voltage side, and V ge(on) is not included in this region. In this case, almost no vibration is found in the waveform of Q g in the dynamic characteristics. This is in contrast to the conventional IEGT in which V ge (on) is in the V ge region exhibiting negative capacitance and the waveform of Q g violently vibrates in the dynamic characteristics (see FIG. 13 ).
[0072] In the instant embodiment, resistance value R float of the floating resistor 34 is adjusted by the shape of the second n-type emitter layers 32 locally formed as isolated regions in the surface layer of the second p-type base layer 18 and the shape of the via contact 30 . Adjustment of the resistance value R float to an appropriate value contributes to preventing the V ge (on) from being included in the V ge region exhibiting the negative capacitance and preventing vibrations of V ge and high dV/dt caused thereby while maintaining the IE effect.
[0073] FIG. 6A is a graph showing a relation of dV/dt and on-voltage relative to the resistance value R float of the floating resistor, which is obtained by simulation. FIG. 6B is a graph showing a relation of the range NCR of V ge exhibiting negative capacitance and on-voltage relative to the resistance value R float of the floating resistor.
[0074] In these graphs, V ce (sat) is the collector-emitter voltage (saturation voltage) in the on-sate, V ge (on) is the gate-emitter voltage under no vibrations in the mirror period, and V th is the gate threshold voltage. Conditions of IEGT used in the simulation are identical to those explained in conjunction with FIG. 4 except the parameters of this simulation. The desirable range of the resistance value R float of the floating resistor 34 is the range where V ce (sat) is low and dV/dt is small in FIG. 6A . Under these experimental conditions, the desirable range of R float is approximately 0.3-3 Ω.
[0075] As shown in FIG. 6B , the higher the resistance value R float of the floating resistor 34 , the lower the value of the range NCR 1 ˜NCR 6 of V ge exhibiting negative capacitance. In NCR 3 ˜NCR 6 where R float is equal to or larger than 5 Ω, their ranges overlap V ge (on) or are located under V ge (on) . This means that V ge (on) of the mirror period is included in the V ge region exhibiting negative capacitance. Therefore, V ge vibrates and rises in a short time. Here is the problem that a large dV/dt is brought about by a sudden flow of the collector current.
[0076] On the other hand, the range of V ge in the instant embodiment belongs to NCR 1 and NCR 2 where R float is equal to or lower than 3 Ω, and these ranges are positioned above V ge (on) . In this case, since V ge takes the turn-on state before affected by the negative capacitance, overshoot of V ge is prevented, and dV/dt is controlled in an appropriate value. The aforementioned relation between R float and V ge (on) has been described in U.S. patent application No. 10,354,048, the contents of which are incorporated herein by reference.
[0077] As such, according to the IEGT 1 of the instant embodiment, it is possible to realize a semiconductor element excellent in controllability of dV/dt without losing the V ce (sat) characteristics by the IE effect.
Second Embodiment
[0078] FIG. 7 is a plan view schematically showing the configuration of a semiconductor device according to the second embodiment of the invention. The IEGT 3 shown here includes a second emitter layers 38 extending in form of an island to contact at its opposite ends with the trenches defining each dummy cell region DC. The contact region Rec 4 of the via contact with the emitter electrode 28 in each dummy cell region DC includes only the central portion of the top surface of the second emitter layer 38 and its peripheral portion. The other configuration of the IEGT 3 is substantially identical to that of the IEGT 1 shown in FIG. 1 .
[0079] Also when the island-shaped second emitter layer 38 is used for emitter contact, functions and effects of the IEGT 3 of this embodiment are substantially the same as the first embodiment.
Third Embodiment
[0080] FIG. 8 is a plan view schematically showing the configuration of a semiconductor device according to the third embodiment of the invention. Similarly to the IEGT 1 shown in FIG. 1 , the IEGT 4 shown here comprises second emitter layers 32 selectively formed as isolated regions in the surface layer of each second base layer 18 to make a pair, both of which are in contact with trenches TR at their respective ends. On the other hand, the second emitter regions 32 and the second base layer 18 are connected to the emitter electrode 28 in a contact region Rec 40 similar to the emitter contact in the main cell region MC via a via contact not shown.
[0081] The IEGT 4 according to the instant embodiment having this configuration also has the same functions and effects as those of the first embodiment.
Fourth Embodiment
[0082] FIG. 9 is a plan view schematically showing the configuration of a semiconductor device according to the fourth embodiment of the invention. The IEGT 5 shown here comprises a second emitter layer 38 having the same geometry as that of the IEGT 3 shown in FIG. 7 and located in the surface layer of each second base layer 18 . The second emitter layers 38 and the second base layer 18 are connected to the emitter electrode 28 in the contact region Rec 40 , which is similar to that of the IEGT 4 according to the third embodiment already explained, via a via contact not shown.
[0083] The IEGT 5 according to the instant embodiment having this configuration also has the same functions and effects as those of the first embodiment.
Fifth Embodiment
[0084] FIG. 10 is a cross-sectional view schematically showing the configuration of a semiconductor device according to the fifth embodiment of the invention. The foregoing embodiments have been explained taking vertical type IEGTs 1 , 3 through 5 . In the instant embodiment, however, a lateral type power semiconductor device equivalent to the former IEGT in function is taken as an example.
[0085] The IEGT 6 shown in FIG. 10 is formed on a SOI (silicon-on-insulator) substrate having a semiconductor support layer 64 , insulating layer 62 and a semiconductor active layer 60 . The active layer 60 is used as a high-resistance n-type drift layer (n-type base layer) 10 . On a right portion of FIG. 10 , a p-type collector layer 66 and a collector electrode 68 are located. In a region of a left portion of FIG. 10 , which is remote from the p-type collector layer 66 , a p-type base layer is formed on the n-type drift layer 10 , and trenches TR are formed from the top surface of the p-type base layer. Thus, the p-type base layer is divided to the first base layer 16 of the main cell region MC and the second base layer 18 of the dummy cell region DC. Around the trenches TR, the same structure as the upper part of the IEGT 1 of FIG. 2 is formed.
[0086] In the IEGT 1 shown in FIG. 2 , having the vertical structure in which the collector electrode 26 and the emitter electrode 28 are formed to sandwich the substrate, the main current flows vertically through the n-type drift layer 10 . In contrast, in the IEGT 6 shown in FIG. 11 , having the lateral type structure in which the collector electrode 68 and the emitter electrode 28 are located on a common side of the substrate, the main current flows laterally in the n-type drift layer 10 . In the other respects, however, both these types of devices work under identical operational principles. As such, the present invention is applicable not only to vertical type IEGTs but also to lateral type IEGTs.
[0087] The invention has been explained by way of some embodiments. These embodiments, however, should not be construed to any limitation of the present invention. Rather, the present invention should be understood to include all possible embodiments and modification to the shown embodiments which can be embodied without departing from the scope and spirit thereof as set forth in the appended claims. | A semiconductor device includes: a drift layer of a first conductivity type; a collector layer of a second conductivity type located on the drift layer; a collector electrode located on the collector layer; a base layer of the second conductivity type located in a region isolated from the collector layer on the drift layer; a plurality of trenches formed at certain intervals to extend from the top surface of the base layer into the drift layer and thereby divide the base layer to main cell regions and dummy cell regions; a first emitter layer of the first conductivity type selectively formed in the surface layer of the base layer in each main cell region to extend along adjacent one of the trenches; gate electrodes formed in the trenches sandwiching each main cell region among said plurality of trenches via a gate insulating film; an emitter electrode located over the base layer and the first emitter layer in each main cell region; and a second emitter layer of the first conductivity type selectively formed so as to be scattered in the surface layer of the base layer in each dummy region and having a surface area smaller than that of the first emitter layer. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a zoom lens for use in a TV camera or the like.
2. Related Background Art
The zoom portion of a zoom lens can be controlled to move the lens position to thereby increase or decrease the photographing angle of view, but when the focus position of the zoom lens is controlled, the lens position is likewise moved, whereby the angle of view is varied. That is, even if a desired angle of view is set by the zoom portion, the set angle of view is fluctuated by the control of the focus portion. Therefore, there has been proposed a zoom lens having the so-called angle of view fluctuation correcting function of controlling the zoom portion so that any fluctuation in the angle of view may not occur when the focus portion is controlled.
FIG. 10 of the accompanying drawings shows a flow chart of the zooming operation including the angle of view correcting operation in a zoom lens of a type which controls the position of the lens. In this zoom lens, data are inputted from zoom demand and focus demand (steps 53 and 54 ), and when there is the input of data from focus demand, a zoom command position for angle of view fluctuation correction is calculated (steps 58 and 61 ). On the basis of the result of this calculation, a motor for driving the zoom portion is driven (step 62 ).
Now, some of zoom lenses have the function of limiting the driving range of the zoom portion (the so-called tracking function). In the zoom lens of which the wider angle of view and higher magnification are progressing year by year, when the zoom portion is set to the wide-side, even a person or persons or the like around an object to be photographed who are not wanted to be photographed may come into the image field, and on the other hand, when the zoom portion is set to the tele-end, the object to be photographed may be too much enlarged to be contained in the image field. In such a situation, the operator of the lens needs always to delicately adjust the zoom stop positions on the wide-side and the tele-side by zoom demand.
So, the tracking function for making it possible to limit the driving range of the zoom position, photographing only and object to be photographed at the wide-end and photographing such an image that the whole image of the object is surely contained in the image field at the tele-end without effecting the delicate adjustment by zoom demand becomes useful.
Also, some of zoom lens apparatuses have, in addition to the above-described tracking function, the function of limiting the driving range of the zoom portion (the so-called F value preferred function) in order to avoid the so-called F drop phenomenon that the brightness of the image field is reduced by the driving of the zoom portion. Although in the zoom lens apparatus, a wider angle of view and a higher magnification are progressing year by year, the size of a lens disposed in the front portion of the zoom lens device is limited because of the size and weight of the lens.
Therefore, brightness equal to that on the wide-side cannot be kept in the entire zoom area and there occurs the F drop phenomenon that when the zoom portion is driven from a certain position to the tele-side, the brightness of the image field becomes dark in spite of the set value of a quantity of light setting device (aperture) being constant. The F value preferred function is the function of calculating a zoom position at which the F drop phenomenon occurs from the value of the aperture in such a case, limiting the driving range of the tele-side at the calculated zoom position and thereby preventing the occurrence of the F drop phenomenon within the driving range of zoom.
Also, in a large lens used in a TV camera, usually with a view to protect a driving portion, the range of a zoom portion and a focus portion which is narrower than a driving end in mechanism is used as an ordinary driving area. Accordingly, when a zoom position command exceeds a position corresponding to wide-end limit data and tele-end limit data set to avoid being driven to the above-mentioned driving end in mechanism, the zoom position command is limited at a wide-end limit position or a tele-end limit position.
SUMMARY OF THE INVENTION
One aspect of the application is to provide a lens apparatus which can perform a proper operation when the lens apparatus having the angle of view correcting function is endowed with the tracking function or the zoom range regulating function such as the F value preferred function.
One aspect of the application is to provide a lens apparatus which can perform the angle of view correcting function as far as possible.
One aspect of the application is to achieve the above object by providing, as a zoom lens apparatus which is provided with a focusing optical portion and a zoom optical portion and in which the range of movement of the zoom optical portion is regulated to a predetermined range, a control circuit having a first mode for setting the movement of the zoom optical portion within the aforementioned regulated range and a second mode for permitting the focusing optical portion to drive a zoom portion beyond the aforementioned regulated range when the fluctuation in angle of view by movement of the focusing optical portion is corrected with the zoom portion movement.
One aspect of the application is to achieve the above objects by providing, in a zoom lens apparatus provided with a focusing optical portion, a zoom optical portion and quantity of light varying means for variably setting the quantity of light passing through the optical portions, a regulating circuit for regulating the range of movement of the zoom portion so that a variation in the quantity of passing light by the movement of the zoom optical portion may not decrease below the set quantity of light, and a control circuit having a first mode for driving the zoom optical portion within the range of movement regulated by the regulating circuit and a second mode for permitting the focusing optical portion to drive the zoom optical portion beyond the range of movement regulated by the regulating circuit when the fluctuation in angle of view by movement of the focusing optical portion is corrected with the zoom portion movement.
One aspect of the application is to achieve the above objects by providing, in a zoom lens apparatus which is provided with a focusing optical portion and a zoom optical portion and in which the movement of the zoom optical portion is regulated to a second movement end inside a first movement end in an area in which the zoom optical portion is movable, a control circuit for permitting the focusing optical portion to drive the zoom optical portion toward the first movement end beyond the second movement end when the fluctuation in angle of view by movement of the focusing optical portion is corrected with the zoom optical portion movement.
Other objects of the present invention will become apparent from the following description of some embodiments of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the construction of a zoom lens apparatus which is an embodiment of the present invention.
FIG. 2 is comprised of FIG. 2 A and FIG. 2B showing flow charts of the operation of the zoom lens apparatus of FIG. 1 .
FIG. 3 shows the construction of a zoom lens apparatus which is another embodiment of the present invention.
FIG. 4 is comprised of FIG. 4 A and FIG. 4B showing flow charts of the operation of the zoom lens apparatus of FIG. 3 .
FIG. 5 shows the construction of a zoom lens apparatus which is another embodiment of the present invention.
FIG. 6 is comprised of FIG. 6 A and FIG. 6B showing flow charts of the control of the zoom lens apparatus of FIG. 5 .
FIG. 7 is a flow chart of an electrical end data calculating process in the zoom lens apparatus of FIG. 5 .
FIG. 8 is a flow chart of a zoom position command limit process in the zoom lens apparatus of FIG. 5 .
FIG. 9 shows the relations among a zoom portion, a mechanical end and an electrical end in the zoom lens apparatus of FIG. 5 .
FIG. 10 is a flow chart of the control of a zoom lens apparatus according to the prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the construction of a zoom lens 101 which is an embodiment of the present invention. The reference numeral 4 designates a CPU (control means), and zoom demand 1 and focus demand 2 are connected to this CPU 4 . From the zoom demand 1 , zoom speed data (zoom operation information) corresponding to the operation speed thereof and zoom tracking limit data for limiting a driving tolerance for the zooming of a zoom portion Z are inputted to the CPU 4 . From the focus demand 2 , focus control data (focus operation information) corresponding to the operated amount thereof is also inputted to the CPU 4 . Also, an angle of view correction preferred mode setting switch 3 is connected to the CPU 4 . When this angle of view correction preferred mode setting switch 3 is ON, the angle of view fluctuation correcting function is preferred than the tracking function (a first mode), and when this switch 3 is OFF, the tracking function is preferred than the angle of view fluctuation correcting function (a second mode).
One of the outputs of the CPU 4 is connected through an amplifier 5 to a motor 7 for driving a lens constituting the zoom portion Z. The zoom portion Z is provided with a position detector 8 for detecting the absolute position of the lens. The position detector 8 is connected to the CPU 4 .
Another output of the CPU 4 is connected through an amplifier 6 to a motor 12 for driving a lens constituting a focus portion F. The focus portion F is provided with a position detector 13 for detecting the absolute position of the lens. The position detector 13 is connected to the CPU 4 .
Also, another output of the CPU 4 is connected through a D/A converter 17 to a TV camera 103 . Thereby, follow signals indicative of the various states of the zoom lens 101 , such as zoom follow data indicative of the lens position of the zoom portion Z, and iris follow data indicative of the aperture value of an aperture device (not shown) are communicated to the camera 103 .
Also, a non-volatile memory 18 storing therein data for angle of view correction calculation is connected to the CPU 4 . Here, the data for angle of view correction calculation will be briefly described.
In advance, the driving range of the lens of the zoom portion Z is divided into any number n and the driving range of the lens of the focus portion F is likewise divided into any number m, and the output data of counters for measuring output pulses in the position detectors 8 and 13 are calculated. Also, the angles of view at the ith division point of zoom and at the jth division point of focus are found by optical calculation and likewise, the angles of view at the ith division point of zoom and the (j+1)th division point of focus, the (i+1)th division point of zoom and the jth division point of focus, and the (i+ 1 )th division point of zoom and the (j+1)th division point of focus are found by optical calculation, and the relation among the lens position of the zoom portion Z (hereinafter referred to as the zoom position), and the lens position of the focus portion F (hereinafter referred to as the focus position) in an area surrounded by these four points and the angles of view is approximated by the equation of a plane containing three of the four points. By applying the equation of this approximate plane, the angle of view can be indicated by a function (1) expression having the zoom position and the focus position as variables.
ω=Cz×Pz+Cf×Pf+D (1)
where ω represents the magnitude of the angle of view, Cz represents the coefficient of the approximate plane relative to the zoom position, Pz represents the zoom position, Cf represents the coefficient of the approximate plane relative to the focus position, Pf represents the focus position, and D represents the constant term of the approximate plane.
The coefficients Cz, Cf and D of the equation of the approximate plane in which the relation among the zoom position, the focus position and the angle of view has been found in this manner are mapped and stored in the memory 18 .
The flow charts of FIGS. 2A and 2B show a series of operations in the above-described zoom lens. The CPU 4 proceeds to a step 1 immediately after the closing of a power source switch, and initializes the interior of the CPU 4 . Also, it effects the initialization of the lens constituting the zoom portion Z by the use of the outputs from the position detector 8 , and effects the initialization of the lens constituting the focus portion F by the use of the outputs from the position detector 13 .
Next, at a step 2 , the initialization of the communication with the zoom demand 1 and the focus demand 2 is effected. Here the initializing operation is terminated, and shift is made to the ordinary operation of controlling the zoom portion Z and the focus portion F in conformity with the outputs from the zoom demand 1 and the focus demand 2 .
First, at a step 3 , normalized zoom speed data Zspeed is inputted from the zoom demand 1 , and further at a step 4 , normalized focus control data Fdata is inputted from the focus demand 2 .
Next, at a step 5 , zoom tracking limit data is inputted from the zoom demand 1 , and at a step 6 , the zoom speed data inputted from the zoom demand 1 is integrated by the use of expression (2), and normalized zoom position data Zdata is calculated.
Zdata=Zbuf+K×Zspeed (2)
where Zbuf: the zoom position data during the previous sampling,
k: any integration constant.
Also, at a step 7 , the output from the angle of view correction preferred mode switch 3 is introduced, and at a step 8 , the state of the angle of view correction preferred mode switch 3 is judged. If the angle of view correction preferred mode switch 3 is ON, an angle of view correction preferred flag is set at a step 9 A, and advance is made to a step 10 . If on the other hand, at the step 8 , the angle of view correction preferred mode switch 3 is OFF, the angle of view correction preferred flag is cleared at a step 9 B, and advance is made to a step 10 .
At the step 10 , the angle of view correction preferred flag is judged. If the angle of view correction preferred flag is set, a mode in which the angle of view fluctuation correcting function is preferred than the tracking function is entered.
In this angle of view correction preferred mode, at a step 11 A, angle of view correction calculation is performed by the use of the zoom position data Zdata and focus control data Fdata inputted from the focus demand 2 , and a zoom position command is calculated.
Here, the angle of view correction calculation will be briefly described. First, by the use of expression (3), the normalized focus position data Fdata is converted into a focus position command Focus corresponding to the output of the counter in the position detector 13 .
Focus=Far+Fdata/NOM×(Near−Far) (3)
where Far: infinite end focus command,
Near: Near end focus position command,
NOM: maximum value of normalized focus position data.
Next, the coefficient of the equation of an approximate plane corresponding to an area including the values of the counters in the position detectors 8 and 13 is inputted from the memory 18 . The inputted coefficient is substituted for Cz, Cf and D of expression (1), the value of the counter in the position detector 8 is substituted for Pz, and the value of the counter in the position detector 13 is substituted for Pf, whereby a standard angle of view ωorg is calculated.
Next, the coefficient of the equation of an approximate plane corresponding to an area including the value of the counter in the position detector 8 and the focus position command Focus is inputted from the memory 18 . The inputted coefficients Cz′, Cf′, D′, the standard angle of view ωorg and the focus position command Focus are substituted for expression (4), whereby a zoom position command Zoom corresponding to the output of the counter in the position detector 8 is calculated.
Zoom=(ωorg−Cf′×Focus−D′)/Cz′ (4)
After angle of view correction calculation has been thus performed, advance is made to a step 14 , where the position control calculation of zoom is performed by the use of the zoom position command Zoom after the correction calculation and the value of the counter in the position detector 8 , and advance is made to a step 15 , where the result of the calculation at the step 14 is outputted to the amplifier 5 , and the motor 7 is driven.
Thereby, for example, even when the zoom position command for angle of view fluctuation correction exceeds the tracking limit data, the zoom portion Z is driven without the zoom position command being limited by the tracking limit data until the zoom position arrives at a position corresponding to the zoom position command for angle of view fluctuation correction, whereby the angle of view is kept constant. Accordingly, the angle of view correcting function can be prevented from not working at a tracking limit point and the angle of view can be prevented from being suddenly fluctuated.
On the other hand, if at the step 10 , the angle of view correction preferred flag is cleared, a mode in which the tracking function is preferred than the angle of view fluctuation correcting function is entered.
In this tracking limit preferred mode, at a step 11 B, angle of view correction calculation is performed by the use of the zoom position data Zdata and the focus control data Fdata inputted from the focus demand 2 , and the zoom position command is calculated. The angle of view correction calculation here is the same as the angle of view correction calculation at the step 11 A.
Next, at a step 12 , whether the zoom position command after the correction calculation exceeds the tele-side limit data of the tracking limit data and is further on the tele-side, or exceeds the wide-side limit data and is further on the wide-side or within the range of the tele-side limit data and the wide-side limit data is judged.
If the zoom position command exceeds the tele-side tracking limit data, advance is made to a step 13 A, where the zoom position command is limited by the tele-side tracking limit data, and advance is made to a step 14 . If the zoom position command exceeds the wide-side tracking limit data, advance is made to a step 13 B, where the zoom position command is limited by the wide-side tracking limit data, and advance is made to a step 14 . If the zoom position command is within the range of the tele-side limit data and the wide-side limit data, advance is intactly made to a step 14 .
The position control calculation of zoom is performed by the use of the zoom position command limited at the steps 13 A and 13 B or the zoom position command intactly regarded as being effective because it is within the range of the tele-side limit data and the wide side limit data and the value of the counter in the position detector 8 , and advance is made to a step 15 , where the result of the calculation at the step 14 is outputted to the amplifier 5 , and the motor 7 is driven.
As described above, in the tracking preferred mode, for example, when the zoom position command for angle of view fluctuation correction exceeds the tracking limit data, the zoom position command is limited by the tracking limit data, and the zoom driving range for angle of view fluctuation correction is limited to within the range of the tracking limit. Therefore, for example, when it is desired to keep the quantity of photographing light constant, the reduction in the quantity of photographing light by the zoom portion Z exceeding the range of the tracking limit for angle of view fluctuation correction on the tele-side and being further driven to the tele-side can be prevented.
The steps 3 to 15 are repetitively executed until the power source is cut off after the driving of the motor at the step 15 .
While in the above-described embodiment, description has been made of a case where whether the zoom position command exceeds the tracking limit data, i.e., the allowable end of the driving of the zoom portion is judged and the angle of view fluctuation correction control of the zoom portion is effected, the present invention can also be applied to a case where whether the zoom position demand is outside a predetermined driving command is discriminated and the angle of view fluctuation correction control of the zoom portion is effected.
Also, both of the tele-side tracking limit data and the wide-side tracking limit data in the above-described embodiment may be set to the intermediate position between the tele-end and the wide-end, or one of them may be set to the tele-end or the wide-end.
While the above embodiment has been described with respect to a zoom lens mounted on a TV camera, the present invention is also applicable to zoom lenses mounted on various cameras such as a silver salt camera and a video camera.
FIG. 3 shows the construction of a zoom lens apparatus 101 which is another embodiment of the present invention. The reference numeral 4 designates a CPU (control means), and zoom demand 1 and focus demand 2 are connected to this CPU 4 . From the zoom demand 1 , zoom speed data (zoom operation information) corresponding to the operating speed thereof is inputted to the CPU 4 . Also, from the focus demand 2 , focus control data (focus operation information) corresponding to the amount of operation thereof is inputted. Also, an angle of view correction preferred mode setting switch 3 is connected to the CPU 4 . When this angle of view correction preferred mode setting switch 3 is ON, the angle of view fluctuation correcting function is preferred than the F value preferred function (a first mode, an angle of view holding mode), and when this switch 3 is OFF, the F value preferred function is preferred than the angle of view fluctuation correcting function (a second mode).
One of the outputs of the CPU 4 is connected through an amplifier 5 to a motor 7 for driving a lens constituting a zoom portion Z. The zoom portion Z is provided with a position detector 8 for detecting the absolute position of the lens. An internal counter in this position detector 8 is connected to the CPU 4 .
Another output of the CPU 4 is connected through an amplifier 6 to a motor 12 for driving a lens constituting a focus portion F. The focus portion F is provided with a position detector 13 for detecting the absolute position of the lens. An internal counter in this position detector 13 is connected to the CPU 4 .
Further, the reference numeral 19 denotes an aperture (quantity of light setting means) for setting (or adjusting) the quantity of light passing through an optical system including the zoom portion Z and the focus portion F. This aperture 19 has a light intercepting member for variably setting the passage area of the light, and the position of this light intercepting member (i.e., an aperture value corresponding to the passage area of the light) is detected by a potentiometer 20 . The potentiometer 20 is connected to the CPU 4 through an A/D converter 21 .
Also, another output of the CPU 4 is connected to a TV camera 103 through a D/A converter 17 . Thereby, follow signals indicative of the various states of the zoom lens apparatus 101 , such as zoom follow data indicative of the lens position of the zoom portion Z, and iris follow data indicative of the aperture value of the aperture 19 .
Also, a non-volatile memory 18 storing therein data for angle of view correction calculation and F value limit data corresponding to iris data to be described hereinafter and indicative of the tele-side driving allowable position of the zoom portion Z at which the quantity of light passing through the optical system is not reduced below the set value by the aperture 19 is connected to the CPU 4 .
The flow charts of FIGS. 4A and 4B show a series of operations in the above-described zoom lens apparatus. The CPU 4 proceeds to a step 101 immediately after the closing of a power source switch, and initializes the interior of the CPU 4 . Also, it effects the initialization of the lens constituting the zoom portion Z by the use of the counter output from the position detector 8 , and effects the initialization of the lens constituting the focus portion F by the use of the counter output from the position detector 13 .
Next, at a step 102 , the initialization of the communication with the zoom demand 1 and the focus demand 2 is effected. Here, the initializing operation is terminated, and shift is made to the ordinary operation of controlling the zoom portion Z and the focus portion F in conformity with the outputs from the zoom demand 1 and the focus demand 2 .
First, at a step 103 , normalized zoom speed data Zspeed is inputted from the zoom demand 1 , and further at a step 104 , normalized focus control data Fdata is inputted from the focus demand 2 .
Next, at a step 105 , the voltage of the potentiometer 20 is inputted as iris data through the A/D converter 21 .
Next, at a step 106 , the zoom speed data inputted from the zoom demand 1 is integrated by the use of expression (2), and normalized zoom position data Zdata is calculated.
Zdata=Zbuf+K×Zspeed (2)
where Zbuf: zoom position data during the previous sampling,
K: any integration constant.
Also, at a step 107 , F value limit data corresponding to the iris data inputted at the step 105 is inputted from the memory 18 .
Next, at a step 108 , the output from the angle of view correction preferred switch 3 is introduced, and at a step 109 , the state of the angle of view correction preferred switch 3 is judged. If the angle of view correction preferred switch 3 is ON, an angle of view correction preferred flag is set at a step 110 A, and advance is made to a step 111 . On the other hand, if at the step 109 , the angle of view correction preferred switch 3 is OFF, the angle of view correction preferred flag is cleared at a step 110 B, and advance is made to the step 111 .
At the step 111 , the angle of view correction flag is judged. If the angle of view correction flag is set, a mode in which the angle of view fluctuation correcting function is preferred than the F value preferred function is entered.
In this angle of view correction preferred mode, at a step 112 A, angle of view correction calculation (this calculation is the same as that at the step 11 A of FIGS. 2A and 2B) is performed by the use of the zoom position data Zdata and the focus control data Fdata inputted from the focus demand 2 , and a zoom position command is calculated.
After angle of view correction calculation has been thus performed, advance is made to a step 115 , where the position control calculation of zoom is performed by the use of the zoom position command Zoom after the correction calculation and the counter value of the position detector 8 , and advance is made to a step 116 , where the result of the calculation at the step 115 is outputted to the amplifier 5 , and the motor 7 is driven.
Thereby, for example, even when the zoom position command for angle of view fluctuation correction exceeds the F value limit data and is on the tele-side, the zoom portion Z is driven until the zoom position arrives at a position corresponding to the zoom position command for angle of view fluctuation correction without the zoom position command being limited by the F value limit data, and the angle of view is kept constant. Accordingly, the angle of view correcting function can be prevented from not working at an F value limit point and the angle of view can be prevented from being suddenly fluctuated.
On the other hand, if at the step 111 , the angle of view correction flag is cleared, a mode in which the F value preferred function is preferred than the angle of view fluctuation correcting function is entered.
In this F value limit preferred mode, at a step 112 B, angle of view correction calculation is performed by the use of the zoom position data Zdata and the focus control data Fdata inputted from the focus demand 2 , and the zoom position command is calculated. The angle of view correction calculation here is the same as the angle of view correction calculation at the step 112 A.
Next, at a step 113 , whether the zoom position command after the correction calculation exceeds the F value limit data and is on the tele-side or is more on the wide-side than the F value limit data is judged.
If the zoom position command exceeds the F value limit data and is on the tele-side, advance is made to a step 114 , where the zoom position command is limited by the F value limit data, and advance is made to a step 115 . If the zoom position command is more on the wide-side than the F value limit data, advance is intactly made to the step 115 .
The position control calculation of zoom is performed by the use of the zoom position command limited at the step 114 or the zoom position command intactly regard as being effective because it is more on the wide-side than the F value limit data and the counter value of the position detector 8 , and advance is made to a step 116 , where the result of the calculation at the step 115 is outputted to the amplifier 5 , and the motor 7 is driven.
As described above, in the F value limit preferred mode, when the zoom position command for angle of view fluctuation correction exceeds the F value limit data and is on the tele-side, the zoom position command is limited by the F value limit data, and the zoom driving range for angle of view fluctuation correction is limited to within the F value limit range (quantity of light maintaining range). Accordingly, when it is preferred to keep the quantity of photographing light rather than the angle of view constant, the reduction in the quantity of photographing light by the zoom portion Z being further driven to the tele-side beyond the F value limit position for the purpose of angle of view fluctuation correction can be prevented.
The steps 103 to 116 are repetitively executed until the power source is cut off after the driving of the motor at the step 116 .
While in the above-described embodiment, description has been made of a case where whether the zoom position command exceeds the F value limit data, i.e., the quantity of light maintaining end of the zoom position, is judged and the angle of view fluctuation correction control of the zoom portion is effected, the present invention can also be applied to a case where whether the zoom position command is outside the quantity of light maintaining range is discriminated and the angle of view fluctuation correction control of the zoom portion is effected.
Also, while the above embodiment has-been described with respect to a zoom lens apparatus mounted on a TV camera, the present invention is also applicable to a zoom lens apparatus mounted on various cameras such as a silver salt camera and a video camera.
FIG. 5 shows the construction of a zoom lens which is another embodiment of the present invention. Zoom demand 1 and focus demand 2 are connected to this zoom lens 101 , and the zoom lens 101 is mounted on a TV camera 103 to thereby constitute a camera system.
The zoom demand 1 inputs normalized zoom speed data (a zoom control signal) to a CPU (control means, angle of view control means) 4 in response to a user's operation. Also, the focus demand 2 inputs normalized focus position data to the CPU 4 in response to the user's operation. Instead of the zoom demand 1 and the focus demand 2 , zoom speed data or zoom position data and focus position data may be inputted from the control unit (not shown) of the TV camera 103 to the CPU 4 .
The reference numeral 3 designates an angle of view correction ON/OFF switch for changing over the ON/OFF of the angle of view correcting function, and this switch 3 is connected to the CPU 4 .
One output of the CPU 4 is connected through an amplifier 5 to a zooming motor 7 for driving a zoom portion Z. A rotary encoder 10 for outputting the position of a lens constituting the zoom portion Z (hereinafter referred to as the zoom position) is connected to the zoom portion Z, and the output of this rotary encoder 10 is connected to the CPU 4 through a counter 22 .
The other output of the CPU 4 is connected through an amplifier 6 to a focusing motor 12 for driving a focus portion F. A rotary encoder 27 for outputting the position of a lens constituting the focus portion F (hereinafter referred to as the focus) is connected to the focus portion F, and the output of this rotary encoder 27 is connected to the CPU 4 through a counter 23 .
The reference numeral 20 designates a memory storing therein the coefficients of an approximate plane equation used for angle of view correction calculation, the maximum angle of view and minimum angle of view obtained by the present zoom lens and wide-end which is the driving end of the zoom portion Z by servo and tele-end limit data, and the memory 20 is connected to the CPU 4 .
Here, in the present zoom lens, it is necessary to prevent the zoom portion Z and the driving potion therefore from colliding with a driving end in the mechanism (hereinafter referred to as the mechanical end) to thereby adversely affect the optical performance of the lens or damage a driving system such as a motor because the lens of great weight is moved at high speed. Therefore, as shown in FIG. 9, the wide-end limit position (hereinafter referred to as the wide-side electrical end) as the driving end by servo (predetermined driving end) is set more adjacent to the tele-side than the wide-side mechanical end. The also holds true of the tele-side of the zoom portion Z and the infinity side and near side of the focus portion F.
The CPU 4 is connected to the TV camera 103 through a D/A converter 17 , and communicates various kinds of information of the zoom lens 101 side to the camera 103 . Likewise, the communication of information from the camera 103 side to the lens 101 side is possible.
Reference is now made to the flow charts of FIGS. 6A and 6B to describe a series of operations from immediately after the closing of a power source switch until the motor is driven in the zoom lens of the present embodiment.
The CPU 4 initializes the interior of the CPU 4 immediately after the closing of the power source switch, and proceeds to a step 201 . At the step 201 , the initialization of the zoom portion Z and the focus portion F is effected, and at a step 202 , the communication with the zoom demand 1 and the focus demand 2 is initialized. Further at a step 203 , the maximum angle of view ω max obtained in the present zoom lens is read from the memory 20 . This maximum angle of view ω max is indicative of the maximum value of the angle of view obtained with the zoom portion Z driven from the wide side electrical end to the tele-side electrical end and the focus portion F driven from the infinity side electrical end to the near side electrical end.
At a step 204 , the initial value of wide-end limit data (hereinafter referred to as the wide-side electrical end data) indicative of the wide-side electrical end which is the driving end of the zoom portion Z by servo is read from the memory 20 . This terminates a series of initializing operations, whereafter shift is made to the ordinary operation of controlling the zoom portion Z and the focus portion F in conformity with control data outputted from the zoom demand 1 and the focus demand 2 .
In the ordinary operation, at a step 205 , normalized zoom speed data is first inputted from the zoom demand 1 , and this data is integrated and normalized zoom position data is calculated. Next, at a step 206 , normalized focus position data is inputted from the focus demand 2 .
At a step 207 , the normalized zoom position data obtained at the step 204 is converted into a zoom position command which is the intrinsic data of the present zoom lens indicative of the position of the zoom portion Z. Also, at a step 208 , as on the zoom side, the normalized focus position data inputted from the focus demand 2 is converted into a focus position command which is the intrinsic data of the lens indicative of the position of the focus portion F.
Next, at a step 209 , the values of the counter 22 and counter 23 (hereinafter the value of the counter 22 will be referred to as zoom follow and the value of the counter 23 will be referred to as focus follow) indicative of the positions of the lens constituting the current zoom portion Z and the lens constituting the focus portion F (referred to as the zoom position and the focus position, respectively) are inputted.
Next, at a step 210 , the electrical end data of the zoom portion Z is calculated by the use of the focus follow, etc.
FIG. 7 shows the calculation processing operation of the electrical end limit data at the step 210 . Here, the calculating process of the electrical end limit data will be described with the wide-end side of the zoom portion Z as an example.
At the step 231 of FIG. 7, the angle of view (calculation angle of view) ω 1 , when the focus portion F is at the current position and the zoom portion Z is driven to the wide-side mechanical end is calculated. Subsequently, at a step 232 , the angle ω 1 , and the maximum angle of view ω max inputted from the memory 20 are compared with each other. When the angle of view ω 1 is equal to or greater than the maximum angle of view ω max , that is, when the driving for the angle of view fluctuation correction of the zoom portion Z can be effected and the angle of view can be kept constant even if the focus demand 2 is operated in the entire range, in case that the zoom portion Z is positioned at the electrical end by widening the driving range of the zoom portion Z to the mechanical end, advance is made to a step 233 , where the initial value inputted as the wide-side electrical end data from the memory 20 , i.e., data indicative of the wide-side electrical end preset to avoid the driving to the mechanical end, is set. At a step 234 , a limit flag is cleared so that the zoom position command after the angle of view correction calculation may not be limited at the wide-side electrical end.
On the other hand, if at the step 232 , the angle of view ω 1 is smaller than the maximum angle of view ω max , that is, if the amount of driving of the zoom portion Z for angle of view fluctuation correction is deficient and the angle of view cannot be kept constant even if the zoom portion Z is driven to the mechanical end, in case that the focus demand 2 is operated when the zoom portion Z is positioned at the wide-side electrical end, advance is made to a step 235 .
At the step 235 , the wide-side electrical end data of the zoom portion Z is calculated by the use of the maximum angle of view ω max and the focus follow. The wide-side electrical end data obtained at this time, as shown in FIG. 9, becomes a value indicative of the tele-side position (the position before the wide-side electrical end is arrived at) rather than the initial value inputted from the memory 20 in order to secure the driving range of the zoom portion Z necessary for the angle of view fluctuation correction. At a step 236 , a limit flag is set to limit the zoom position command after the angle of view correction calculation at the wide-side electrical end, and return is made to the step 211 of FIGS. 6A and 6B. Similar calculation and ON/OFF of the limit flag are also performed on the tele-side.
At a step 211 , the state of the angle of view correction ON/OFF switch 3 is judged. When the angle of view correction ON/OFF switch 3 is set to ON, advance is made to a step 212 , where the zoom speed data inputted from the zoom demand 1 is judged. When the zoom speed data is 0, that is, when the zoom demand 1 is not operated, advance is made to a step 213 , where whether a standard angle of view ωorg to be maintained constant is set is confirmed. When the standard angle of view ωorg is cleared, that is, when the angle of view correction ON/OFF switch 3 has been changed over from OFF to ON, or when the operation of the zoom demand 1 has ended, the zoom follow and the focus follow and calculation coefficients conforming to them are inputted from the memory 20 , and the standard angle of view ωorg is calculated, and advance is made to a step 215 .
If at the step 213 , the standard angle of view ωorg is set, jump is intactly made to the step 215 .
At the step 215 , calculation for correcting the zoom position command converted at the step 207 to a zoom position command for maintaining the angle of view at the standard angle of view ωorg is performed by the use of the standard angle of view ωorg and the focus position command calculated at the step 208 . Thereafter, at a step 216 , the limit flag is judged, and if the limit flag is set, at a step 217 , the zoom position command after the angle of view correction calculation is limited by the electrical end data obtained at the step 210 , and advance is made to a step 220 .
On the other hand, if at the step 216 , the limit flag is cleared, the zoom position command after the angle of view correction calculation is not limited but jump is made to the step 220 in order to widen the driving range of the zoom portion Z for angle of view fluctuation correction to the mechanical end.
Also, if at the step 211 , the angle of view correction ON/OFF switch 3 is set to OFF and if at the step 212 , the zoom speed data is not 0 (the zoom demand 1 is operated), advance is made to a step 218 , where the standard angle of view ωorg is cleared. Further, at a step 219 , the zoom position command is limited by the electrical end data obtained at the step 210 , and jump is made to the step 220 .
FIG. 8 shows the limit processing operation for the zoom position command at the step 217 and the step 219 . Here, the limit operation for the zoom position command will be described with the wide-end side of the zoom portion Z as an example.
First, at a step 241 , whether the zoom position command corresponds to the wide-side with respect to the position indicated by the wide-side electrical end data is discriminated. If it corresponds to the wide-side, advance is made to a step 242 , where the zoom position command is limited by the wide-side electrical end data, and if it corresponds to the tele-side, advance is intactly made to the step 220 of FIGS. 6A and 6B.
At the step 220 , the position control calculation of the zoom portion Z is performed by the use of the zoom position command and the value of the counter 22 and the position control calculation of the focus portion F is performed by the use of the focus position command and the value of the counter 23 . At a step 221 , the results of the calculations at the step 220 are outputted to the amplifier 5 and the amplifier 6 , respectively, and the motor 7 and the motor 12 are driven to thereby drive-control the zoom portion Z and the focus portion F. Thereafter, the steps 205 to 221 are repetitively executed until the power source is cut off.
As described above, in the present embodiment, in case that the driving range of the zoom portion Z is widened to the mechanical end, when the angle of view can be kept constant (the calculated angle of view ω 1 is equal to or greater than the maximum angle of view ω max ) even if the focus demand 2 is operated over the entire range when the zoom portion Z is positioned at the electrical end, the driving allowable end of the zoom portion Z which can be operated by the zoom demand 1 is set to the electrical end (steps 231 to 233 ) and the zoom position command after the angle of view correction calculation is not limited at the electrical end, but the driving range of the zoom portion Z for the angle of view fluctuation correction is widened to the mechanical end.
In other words, if the driving range of the zoom portion Z for the angle of view fluctuation correction is sufficient when the zoom portion Z is driven to the electrical end by the zoom speed data from the zoom demand 1 , the driving to the mechanical end exceeding the electrical end is permitted only for the driving of the zoom portion Z for the angle of view fluctuation correction.
Thereby, the angle of view fluctuation correcting function can always be made to work effectively even if the focus portion F is driven over the entire driving range with the zoom portion Z driven to the electrical end.
The amount of driving of the zoom portion Z for the angle of view fluctuation correction is small (the driving speed is also small) and therefore, even if the zoom portion Z is driven to the mechanical end, the driving portion will not be damaged or the optical performance of the zoom portion Z will not be adversely affected.
On the other hand, in case that the focus demand 2 is operated over the entire range when the zoom portion Z is positioned at the electrical end, when the amount of driving of the zoom portion Z for the angle of view fluctuation correction is deficient and the angle of view cannot be kept constant (the angle of view ω 1 is smaller than the maximum angle of view ω max ) even if the zoom portion Z is driven to the mechanical end, the electrical end data corresponding to the position before the original electrical end is arrived at is calculated (at step 35 ), and the driving range of the zoom lens portion 7 which can be operated by the zoom demand I is narrowed to thereby secure a driving range necessary for the zoom portion Z to effect the angle of view fluctuation correction.
In other words, if the driving range of the zoom portion Z for the angle of view fluctuation correction becomes deficient when the zoom portion Z is driven to the electrical end by the zoom speed data from the zoom demand 1 , the driving allowable end of the zoom portion Z by the operation of the zoom demand 1 is set to the position before the electrical end is arrived at so as to ensure the driving range. Thereby, irrespective of the driving position of the zoom portion Z by the zoom demand 1 , when the focus portion F is driven over the entire driving range, the angle of view fluctuation correcting function can be made to work effectively.
While in the present embodiment, description has been made of a case where the driving allowable end of the zoom portion Z by the zoom demand 1 is variably set to the electrical end or the position before it is arrived at, the driving tolerance of the zoom portion by the zoom demand may be variably set to the range up to the electrical end or the range up to the position before the electrical end is arrived at. | This invention relates to a TV lens apparatus having the angle of view maintaining function of maintaining the angle of view constant. In the present invention, in a state in which the lens has been operated by the angle of view maintaining function when the zoom lens is endowed with the function of regulating the movement range of the zoom lens to a predetermined range, even if the movement range of the zoom lens is regulated, the zoom lens is driven beyond the regulated range to thereby take matching between the angle of view maintaining function and the lens movement range regulating function. | 6 |
FIELD OF THE INVENTION
Embodiments of the present invention relate to automated identification and data collection.
BACKGROUND OF THE INVENTION
Conventional automated identification systems may in addition perform data collection functions. Such systems typically include tags, readers, and computer systems that perform application programs generally for monitoring the position and movement of tagged items, persons, and animals. These systems have wide utility in personal, commercial, government, education, and scientific fields including, for example, managing inventory (e.g., auto parts, mail, baggage), capturing point of sale transactions (e.g., groceries, utility meters), capturing product life cycle information (e.g., truck tires), controlling access to facilities and equipment by authorized persons, and monitoring the movements of vehicles, livestock, prisoners, soldiers, children, and employees, to name a few applications. Information and statistics from automated identification systems may support business decision making (e.g., throughput planning, insurance claims, valuation of a business, improvement of a supply chain).
Readers and computer systems coupled to the readers for performing application programs represent functionality installed at an investment cost that is generally returned over time by the value of the automated identification and data provided by the system. It is desirable to reuse this installed investment as additional applications for automated identification and/or data collection are discovered. One approach is to upgrade readers and computer systems to read additional types of tags and process additional types of information. Typically, upgrading software is less expensive than upgrading hardware.
Unfortunately, software for use in automated identification systems is difficult to design, deploy, and upgrade in part because determinations that are fundamental to system functions are generally made in the application program. For example, readers that report raw data to an application program place the burden of raw data analysis on the application program for an increasing quantity and perhaps decreasing quality of raw data as the number of readers in an installation increases. Raw data communication may also adversely consume the capacity of communication media including wired and wireless networks between readers and computer systems performing the application programs. The fundamental notion of the location of a tag is typically determined in the application program based on the identity of the tag, the identity of the reader reporting the tag, and the installed location of the reader. Another fundamental notion, to control equipment in the neighborhood of the tag, is conventionally accomplished by the application program. Consequently, there remains a need to reserve to the application program operating in an upper layer of the system those functions that are unique to the application (e.g., inventory replenishment thresholds) and to perform in a lower layer of the system functions that may be useful in one or more of several applications (e.g., reporting the location of a tagged item).
As automated identification systems expand to cover more items, it is desirable to be able to add equipment and software with a minimum of reconfiguration of existing equipment and software. It is also desirable to add diverse readers and diverse application programs with a minimum of reconfiguration of the existing investment as new applications in the same locations are identified. For example, an employer's system may initially control access to facilities by employees. Later the employer may desire to perform operations research and/or capital equipment utilization research. These additional applications may require diverse tags, diverse readers, and additional application program resources. It is desirable to make these additional application programs operable with a minimum of additional investment.
Without systems and methods according to various aspects of the present invention, the proliferation and integration of reliable and scalable automated identification and data collection systems will be impeded. Consequently, the costs of such systems will not reflect greater economies of scale. Benefits to the public will not be realized including material benefits of lower costs of goods (e.g., owing to less shrinkage), lower costs of services (e.g., package delivery), and other benefits (e.g., lower the risk of losses due to ineffective security).
SUMMARY OF THE INVENTION
A method, in an implementation according to various aspects of the present invention, may be performed by a server coupled to a network. The network may include a plurality of tags, a plurality of readers that read the tags, a plurality of appliances that service the readers to provide information, and a plurality of actuators responsive to the appliances. The server performs an application program in accordance with the information. The method includes in any order: (a) sending via the network a rule for use by an appliance of the plurality, the rule having a subject and a predicate, the subject specifying a criteria, the predicate specifying an action to be taken in response to the criteria being met; and (b) receiving via the network identification of a particular tag of the plurality of tags, the appliance having applied the rule with respect to the particular tag. Applying the rule includes in any order: ( 1 ) meeting the criteria in accordance with information from a particular reader of the plurality regarding the tag and ascertaining a physical location, the subject of the rule being insufficient to identify the particular reader; and ( 2 ) to accomplish the action, activating a particular actuator of the plurality in accordance with the location, the predicate of the rule being insufficient to identify the particular actuator.
A method, in another implementation according to various aspects of the present invention, may be performed by an appliance coupled to a network. The network includes a plurality of tags, a plurality of readers that read the tags, and a plurality of appliances. The appliances service the readers to provide information for a server, coupled to the network. The server performs an application program in accordance with the information. The method includes in any order: (a) determining an unallocated capacity for service by the appliance; (b) determining a load for servicing a reader of the plurality; and (c) if the load fits within the unallocated capacity, providing a signal to the network for another appliance of the plurality, the signal for indicating that the appliance can service the reader.
A method, in another implementation according to various aspects of the present invention, may be performed by an appliance coupled to a network. The network includes a plurality of tags, a plurality of readers that read the tags, and a plurality of appliances. The appliances service the readers to provide information for a server, coupled to the network. The server performs an application program in accordance with the information. The method includes in any order: (a) determining a figure of merit of communication between tags and readers; (b) sending information for a reader to adjust communication with the tags in accordance with the information.
BRIEF DESCRIPTION OF THE DRAWING
Embodiments of the present invention will now be further described with reference to the drawing, wherein like designations denote like elements, and:
FIG. 1 is a functional block diagram of an automated identification and data collection system according to various aspects of the present invention;
FIG. 2 is a data flow diagram of a method for load balancing in the system of FIG. 1 ; and
FIG. 3A–3F is an entity relationship diagram for a portion of the data stored in the system of FIG. 1 ;
FIG. 4 is a data flow diagram of a method for improving reliability in the system of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A system in an exemplary implementation according to various aspects of the present invention provides improved monitoring, tracking, and/or control solving the problems discussed above. Monitoring, tracking, and control may employ any conventional automated identification technology, any conventional open loop or closed loop control technology, and may further include any conventional data collection, analysis, storage, and reporting technology. The functions of such a system may be divided into two or more layers, each layer including one or more engines.
An engine may be implemented with any conventional combination of integrated circuits, circuit modules, processors, memory devices (e.g., semiconductor, magnetic, and optical data storage subsystems), firmware, and/or software. Data communication between layers may include any conventional communication technology including point-to-point, bus, and network technologies for cooperation of the engines' processors and processes. Bus and network technologies generally provide communication via links for any mix of one to one, one to many, many to one, and many to many relationships. A link may be physical and/or logical, and may be temporary (e.g., as needed or shared) or permanent (e.g., dedicated).
A logical link may be implemented between at least two software components. A component herein refers to a modular package of processes and data (e.g., classes and objects in the object oriented paradigm). The component generally includes processes forming an interface (i.e., exposed processes) for use of the component by other components. Data of a component is accessed (at least initially) only via one or more exposed processes. In this way, data and unexposed processes are said to be encapsulated in the component.
Encapsulation generally provides functional independence between components and engines. Improved scalability and reliability result from use of independent engines. For example, when a first engine communicates via a logical link with a second engine, both engines may actually be implemented with any number of parallel engines (e.g., for high throughput) and redundant engines (e.g., for failure detection by voting, and automatic fail-over). For example, increasing the capacity or improving the reliability of the first engine may involve installing an additional engine (e.g., in parallel or redundant) with no change to the second engine.
Systems according to various aspects of the present invention encapsulate location information at a layer below the application layer of the system.
For example, system 100 of FIGS. 1–4 includes an application layer, an appliance layer, a monitoring and control layer, and an identification layer. The application layer includes one or more engines for performing functions unique to an application (e.g., inventory management). For example, the application layer of system 100 includes one engine implemented on a set of servers 101 , each server performing a copy of an application program with access to a copy of a data store. Application layer 101 includes server 105 performing application program 112 with access to data store 111 ; and server 106 performing application program 117 with access to data store 116 . Servers 105 and 106 represent any number of servers cooperating to perform application functions in a parallel and/or redundant manner as discussed above. Each server has access via a network 102 that includes lower layer engines.
Network 102 includes a medium 120 for logical links between the application engine and lower layer engines. Links of medium 120 may be implemented with conventional discovery, naming, and session technology, for example for many-to-many relationships among servers and appliances. In one implementation and/or mode of operation, servers relate to appliances in a server/client modality. In another implementation and/or mode of operation, servers and appliances relate as peers.
The appliance layer includes one or more engines for performing services separated from the application layer to improve scalability and separated from the monitoring and control layer to implement compatibility with diverse and legacy readers, actuators, and sensors. For example, the appliance layer of system 100 includes one engine implemented on a set of appliances 121 , each appliance performing a copy of a services process with access to a copy of a data store. Appliance layer 121 includes appliance 125 performing service process 132 with access to data store 131 ; and appliance 126 performing service process 137 with access to data store 136 . Appliances 125 and 126 represent any number of appliances cooperating to perform appliance functions in a parallel and/or redundant manner as discussed above. Each appliance has access via a network 122 that includes lower layer engines.
Network 122 includes a medium 140 for logical links between the appliance engine and lower layer engines. Links of medium 140 may be implemented with conventional discovery, naming, and session technology, for example for many-to-many relationships among appliances and readers, actuators, and/or sensors. In one implementation and/or mode of operation, appliances relate to readers, actuators, and/or sensors in a server/client modality. In another implementation and/or mode of operation, appliances, readers, actuators, and sensors relate as peers.
According to various aspects of the present invention, an application engine sends one or more rules to an appliance engine. A rule may specify data to be made available to the application engine, for example, by a conventional subscription. A rule may specify a conditional subscription in terms of a subject and predicate. The subject may specify criteria (e.g., a logical combination of one or more conventional events). The predicate may specify an action (e.g., one or more conventional alerts) to be performed (or scheduled for performance according to priority). The rule may be evaluated according to a priority associated with the rule and/or criteria (e.g., when data relevant to the criteria become available). Designation of which of several appliances is to store and/or act on a particular rule is typically out of the scope of control of the application engine. In one implementation, rule store 133 (for process 132 ) and rule store 138 (for process 137 ) are maintained as identical copies.
The appliance engine determines, monitors, and maintains accurate location information (e.g., in data stores 131 and 136 ) describing the location of tags, readers, actuators, and sensors. The determination of a location or change in location may give rise to an event. Location information may be absolute (e.g., within a region of a floor of a building) or relative to other tags, readers, actuators, and/or sensors (e.g., within a predefined range, for example 2 meters). Because appliance engines encapsulate location information, location information may be determined in diverse ways with no change to application engines. For instance, a table of fixed locations may be accessed by an appliance engine to determine the location of a reader; or the reader may report its location (e.g., configured at fixed installation, or as determined with access to a global positioning system co-located with the reader).
Consequently, rules may refer to tags, readers, actuators, and/or sensors with reference to an absolute or relative location. For example, a rule may make and absolute reference to a reader on the 2nd floor of the Headquarters building; or, using a relative reference, refer to an actuator that is within a range (e.g., 2 meters) of such a reader or that is at a unique distance (e.g., closest) to such a reader. By referring to a tag, reader, actuator, or sensor with reference to a location, the actual tag, reader, actuator, or sensor may be implemented with parallel and or redundant physical tags, readers, actuators, or sensors providing benefits of scalability and reliability as discussed above. Appliance engine 121 may present diverse readers, actuators, sensors, and tags in an identical manner to application engine 101 permitting the introduction of diversity (e.g., a capability upgrade or integration of existing systems) with no change to the application engine.
The monitoring and control layer includes physically distributed engines for monitoring physical regions for the presence and movement of tagged items (e.g., objects, persons, vehicles, animals), for effecting physical controls in regions (e.g., opening locks on doors, directing surveillance cameras, performing materials handling, vending, providing signals for human interfaces), and for gathering physical measurements from regions (e.g., temperature, traffic counts, audio surveillance, video surveillance). Actuators and sensors may be combined to implement any conventional operator interface (e.g., cash registers, graphical user interfaces, voice recognition, telephone answering, video conferencing). For example, the monitoring and control layer of system 100 includes one or more readers 141 , one or more actuators 142 , and one or more sensors 143 . Readers 141 include reader 144 performing tag I/O process 151 and reader 145 performing tag I/O process 152 . Readers 141 may be functionally diverse or identical, co-located or physically distributed throughout one or more regions. Actuators 142 include actuator 176 and actuator 177 that may be functionally diverse or identical, co-located or physically distributed throughout one or more regions. Sensors 143 include sensor 182 and sensor 183 that may be functionally diverse or identical, co-located or physically distributed throughout one or more regions. One or more readers, actuators, and sensors may co-located to implement an interface for the application. For example, for facility access, a badge reader, door lock actuator, video surveillance sensor, and audio interface (microphone and speaker) may be implemented in close proximity. Readers, 141 , actuators 142 , and sensors 143 represent any number of units cooperating to perform monitoring and control functions in a parallel and/or redundant manner as discussed above. Each reader has access to a network 162 that includes lower layer engines.
Network 162 includes a medium 170 for logical links between readers 141 and the identification layer of system 100 . Links of medium 170 may be implemented in any manner compatible with tags 171 . Links may include discovery, naming, and session technology, for example, for many-to-many relationships among readers and tags. Readers and tags may communicate in any conventional manner. Readers may include transmitters that stimulate tags to initiate communication and/or provide location information to tags. These readers are typically used with other readers having receivers to complete automatic identification and data collection from tags. Readers may also include receivers that scan one or more channels at one or more times to detect signals from tags, and transceivers that interrogate tags.
The identification layer includes tags and devices that perform primitive automatic identification and data collection functions. Tags 171 include tag 172 and tag 173 that may be functionally diverse or identical. Tags 172 and 173 represent any number of co-located or physically distributed tags. Tags may be stationary and/or mobile. Tags may provide reference signals, identification signals, and/or send and receive information stored in tags. Tags may include sensors and/or actuators. In various implementations, communication via medium 170 includes conventional radio frequency identification (RFID), conventional smart card interfaces (e.g., contacts), and scanner interfaces (e.g., magnetic strip and bar code). Tags may emit signals (e.g., infrared), reflect (e.g., back scatter), or absorb signals to convey information.
Objects, persons, and animals to be identified, monitored, tracked, and/or controlled may be physically associated with a tag (e.g., attached to the object, person, or animal). In another implementation, objects, persons, and animals are associated with a reader (e.g., attached or carried on or in the object, person, or animal). In this latter implementation, the information layer includes readers (not shown) with functions as discussed above.
Operation of the appliance encapsulates all aspects of readers, actuators, sensors, and tags. Consequently, services performed by the appliance are scalable and made more reliable primarily by adding appliances to the system with little or no change to application programs. Diverse tags and diverse readers may be supported by adding functionality to the appliances with little or no change to application programs. Application program functions are also scalable and new application programs may be added with little or no change to the networks, appliances, readers, actuators, sensors, and tags.
Location information is encapsulated below the application layer, as discussed above. Any other information from the identification layer is also encapsulated including, for example, tag identification; tag communication protocol, state, and signal strengths; and tag memory contents (if any). Consequently, the information layer functions for an object may be implemented in a scalable and reliable manner using parallel and/or redundant tags (e.g., diverse tags) associated with the object. In other implementations, information layer functions for an object may include parallel and/or redundant readers alone or with tags.
According to various aspects of the present invention, system 100 performs load balancing among appliances 121 in a manner that is transparent to application layer 101 . In one implementation, each appliance determines whether a change in responsibility for servicing any reader, actuator, or sensor may bring about a more uniform distribution of service functions among appliances (e.g., any subset or all appliances); initiates communication among appliances to accomplish such change, and cooperates with other appliances that may initiate other changes.
For example, in appliance 125 , service process 132 cooperates with data store 131 and communicates with other appliances via medium 140 (or 120 ) to accomplish analysis and delegation for load balancing. Service process 132 (and 137 ) may include load balancing process 200 of FIG. 2 . Data store 131 (and 136 ) may include data structures 300 of FIG. 3 . Process 200 includes evaluate own readers' loads process 202 , calculate own capacity process 206 , request other capacities process 210 , reply to others' requests process 212 , plan delegations process 214 , and delegate process 216 . Each process may be performed whenever sufficient data is available (e.g., a multitasking environment).
Evaluate own readers' loads process 202 estimates a load value in a unit of measure suitable for comparing to a capacity value describing the capacity to service readers from appliance 125 . The load value represents a forecast of expected load to occur in a predetermined future time interval (e.g., during the next 10 minutes). A suitable unit of measure may be messages (or packets) per second for messages of generally equal complexity (or length). An average value may be used (e.g., a root-mean-square average). Historical data may be used, such as a moving average. Load values may be based on load experienced in a suitable interval in the past (e.g., a comparable interval an hour ago, a day ago, or a week ago). In one implementation, both an RMS and a peak value are calculated from historical data. Historical data may be acquired from examining message queues where each message is associated with a time received (or enqueued). Load values may be stored (e.g., in readers store 204 ) in association with each reader being serviced by appliance 125 . In another implementation, load values for actuators and sensors are also estimated and stored in an analogous manner.
Calculate own capacity process 206 estimates a capacity value in a unit of measure suitable for comparing to a load value, discussed above. The capacity value represents a forecast of expected capacity to be available for processing messages from readers in a predetermined future time interval (e.g., during the next 10 minutes). A suitable unit of measure may be messages (or packets) per second for messages of generally equal complexity (or length). An average value may be used (e.g., a root-mean-square average). Historical data may be used, such as a moving average. Capacity values may be based on capacity consumed in a suitable interval in the past (e.g., a comparable interval an hour ago, a day ago, or a week ago). In one implementation, both an RMS and a peak value are calculated from historical data. Historical data may be acquired from examining message dequeueing logs where each logged dequeueing operation is associated with a time completed. Capacity values may be stored at each appliance in association with each appliance for analysis of unallocated capacity of each of several appliances. An unallocated capacity may be determined from an estimated capacity reduced to account for estimated load from each reader being serviced by appliance 125 . Estimated loads may be read from readers store 204 . In another implementation, capacity values for servicing actuators and sensors are also estimated and stored in an analogous manner.
Request other capacities process 210 communicates with other appliances (e.g., 126 ) and records in appliances store 208 each estimated capacity as discussed above received in response to the request. Process 210 may make default or zero entries in appliances store 208 for unallocated capacities requested but not timely provided (e.g., due to other appliance too busy to respond). Process 210 may also request others' estimated loads for readers (actuators and sensors) assigned to the others' appliances. Results may be stored in readers (actuators and sensors) store 204 .
Reply to others' requests process 212 reports capacity values to other appliances. Process 212 may read appliances store 208 and prepare suitable messages (e.g., directed or broadcast) in response to requests. In another implementation, process 212 periodically broadcasts estimated capacity values from store 208 . Various values for the period between broadcasts may be used with more frequent broadcasts prior to anticipated busy times.
Plan delegations process 214 determines a load balancing plan based on the unallocated capacity of each appliance and the loads presented by readers (e.g., local to appliance 125 ). A conventional load balancing strategy may be used. To assure that all appliances are operating from the same or compatible portions of a load balancing strategy, appliance 125 may broadcast information identifying and/or describing the plan process 214 has determined. Balancing by and for appliance 125 may be planned with a goal to leave unallocated capacity in each appliance in proportion to a total estimated peak load, and/or a total estimated RMS load expected to be needed at this appliance ( 125 ). Some delegations in a series of planned delegations may appear to further unbalance the load.
Delegate process 216 assures a complete transition of a reader from a first appliance to a second appliance resulting in no lost messages. In one implementation, readers retain a log of received tag information and discard a portion of the log only when instructed to so by an appliance. In this way, tag information originally sent to a now failed appliance can be resent to an operational appliance. Cooperation between appliances to accomplish a delegation may include stopping a subscription for data from a reader sent to the first appliance, starting a subscription for data from the reader to the second appliance.
In another implementation, a failed appliance may be detected. In response to discovery of a failed appliance, an appliance with suitable capacity may reassign a reader (actuator or sensor) from the failed device to the operating appliance itself.
A data structure according to various aspects of the present invention may be referred to by any process involved in analysis and delegation for load balancing, as discusses above. A database may include lists of records having the same structure (e.g., values for the same purpose indicated by a field name). Any two or more values of a data structure (e.g., a record) comprise a tuple by implementing an association (e.g., a relationship) between the values. For example, a database 300 of FIGS. 3A–3F for use by any appliance ( 125 ) implements readers store 204 and appliances store 208 and may be stored in data store 131 and mirrored on any other data store (e.g., 137 ). Database 300 includes lists of records for appliances 302 , readers 312 , actuators 314 , sensors 316 , and locations 318 . Each relationship between lists of records ( 303 – 308 ) may be implemented as a cross reference list associating keys from each list. Each such cross reference list supports many-to-many relationships as may be desired.
A value unique to each record that may serve as a key for indexed access to the respective list is called an ID (short for identifier), for example, Appliance ID, Reader ID, Actuator ID, Sensor ID, and Location ID. A Description field may include any number of fields for particular descriptive information. For example, a description may include a “type” value to classify listed information. A Network ID is a unique identifier to be used in network communication via media 140 . Communication from an appliance with each other appliance, reader, actuator, and sensor is facilitated by unique network addresses. Listed location values may be determined from a receiver for conventional Global Positioning System signals associated with the reader, actuator, or sensor.
System 100 may dynamically control communication between information layer 162 and readers 141 to provide greater reliability than offered by conventional automatic identification systems. For example, a service process (e.g., 132 ) performed by one or more appliances 121 may include a process 400 of FIG. 4 that plans and implements adjustments to communication. Readers 141 and/or sensors 143 may provide information ( 402 , 404 ) to determine ( 406 ) a figure of merit or quality of communication. Adjustments may be planned ( 408 ) and plans may be implemented by commanding readers ( 410 ) to adjust communication via medium 170 and/or by operating ( 412 ) actuators 142 that affect changes in communication via medium 170 .
In one implementation, one or more readers 141 analyze communication via medium 170 and report statistics to one or more appliances. An appliance may subscribe to receive such reports from one or more readers. Statistics may include indications of network utilization as a percent of a predetermined period (e.g., past 5 minutes). Percentages may include a percent for time not receiving because no signal is within range of signal strength, a percent for time receiving within suitable ranges of signal strength and accuracy, and a percent for time receiving within suitable signal strength but without suitable accuracy. Messages may be counted and a ratio may be calculated and reported. For a predetermined period (e.g., 5 minutes) a quantity of messages received with suitable accuracy is divided by a quantity of all messages attempted to be received (e.g., including incomplete messages and inaccurate messages). A noise floor measurement may be made and reported when the reader determines that the medium is probably free of all messages. A noise floor measurement may be made and reported when the appliance determines from sensors (e.g., a spectrum analyzer) that the medium (or a particular channel of interest) is probably free of all messages. The range of signal strengths of signals received with suitable accuracy may be determined and reported.
Commands to readers that may affect improved communication via medium 170 may include commands to change transmitter modulation, message length, message timing, transmitting channel(s), and/or transmitted signal strength to avoid particularly busy or noisy frequency ranges or time periods. Commands may also affect more suitable cooperation among transmitting entities (readers and/or tags) by commanding revised timing parameters that may be more suitable to the total number of transmitting entities competing for use of medium 170 . A failing transmitter or receiver (in a tag or reader) may be commanded to be reset or temporarily disabled.
Actuators that may affect improved communication via medium 170 may include direct and/or indirect actions. Power supplies that supply power to one or more readers may be cycled to reset or temporarily disable transmitters and receivers. When tags receive power via transmissions, an actuator may analogously cycle power to tags or temporarily disable tags. Antenna switches and antenna positioning subsystems for readers may be operated by actuators. In other suitable situations, it may be determined by trial and error or by analysis and/or test that a movable object, person, or animal may be interfering with communication. Actuators may be operated to move the object, person, or animal, or have it moved (e.g., an audio message broadcast at a suitable location).
The foregoing description discusses preferred embodiments of the present invention which may be changed or modified without departing from the scope of the present invention as defined in the claims. While for the sake of clarity of description, several specific embodiments of the invention have been described, the scope of the invention is intended to be measured by the claims as set forth below. | In a system for automatic identification, a method performed by an appliance coupled to a network balances load among appliances. The network includes a plurality of tags, a plurality of readers that read the tags, and a plurality of appliances. The appliances service the readers to provide information for a server, also coupled to the network. The server performs an application program in accordance with the information. The method includes in any order: (a) determining an unallocated capacity for service by the appliance; (b) determining a load for servicing a reader of the plurality; and (c) if the load fits within the unallocated capacity, providing a signal to the network for another appliance of the plurality, the signal for indicating that the appliance can service the reader. Another method performed by an appliance includes in any order: (a) determining a figure of merit of communication between tags and readers; (b) sending information for a reader to adjust communication with the tags in accordance with the information. | 6 |
DOMESTIC PRIORITY
This application is a continuation-in-part of prior application Ser. No. 10/134,354, filed on Apr. 27, 2002 now U.S. Pat. No. 6,800,207.
FIELD OF THE INVENTION
This invention relates generally to methods and devices used with water systems. More particularly, it relates to an improved method and apparatus for exposing water, flowing through a water system, to an ion generator whereby ions are fed into the water flow to prevent fouling of the water system by algae, nuisance invertebrates, microorganisms, and inorganic salts. This invention also specifically relates to an improvement of the inventors' method and apparatus disclosed and claimed in U.S. Pat. No. 6,350,385.
BACKGROUND OF THE INVENTION
It has long been known that algae, nuisance invertebrates, microorganisms, and inorganic salts may foul water systems and lead to very significant water system inefficiencies. These inefficiencies result in increased energy consumption and increased maintenance demands that, in turn, increase overall operational and maintenance costs by several orders of magnitude. Ion generators have been employed in previous attempts to control algae, nuisance invertebrates, and microorganisms. Such ion generators are based on well-known principles of electrochemical reactions, one of which is referred to as electrolysis.
Electrolysis is an electrochemical process by which electrical energy is used to promote chemical reactions that occur on the surface of functionally cooperating electrodes. One electrode, called the anode, involves the oxidation process where chemical species lose electrons. A second electrode, called the cathode, involves the reduction process where electrons are gained. In water, for example, oxygen is generated at the anode and hydrogen is generated at the cathode. The generation of hydrogen and oxygen in fresh water by the process of electrolysis will be weak due to the low electrical conductivity of the water. The oxygen generated aids in the prevention of the deposit of inorganic salts on the electrodes. The function of an ion generator is also to produce metal ions, typically copper ions or silver ions. Metal ion production is accomplished by use of an electrically charged metal anode that comprises atoms of the metal ions that are to be generated. It is the purpose of the ion generator to feed the metal ions out of the generator before they can be deposited on a cathode. The metal ions and oxygen, both of which are produced by the ion generator, are fed into the water stream of the water system to prevent fouling of the system by algae, nuisance invertebrates, microorganisms, and inorganic salts. As previously mentioned, one such system was devised by these inventors and is the subject of U.S. Pat. No. 6,350,385 issued to Holt, et al.
The toxicity of copper and silver to aquatic organisms is well established although the exact mechanism is not well defined. In general, these heavy metals must be in an ionic form in order for them to be toxic to invertebrates, microorganisms and algae. The eradication of microorganisms is attributed to positively charged ions that are both surface active and microbiocidal. These ions attach themselves to the negatively charged bacterial cell wall of the microorganism and destroy cell wall permeability. This action, coupled with protein denaturation, induces cell lysis and eventual death. One advantage to the use of metal ionization is that eradication efficacy is wholly unaffected by water temperature. Chlorine, a commonly used antifouling chemical, is somewhat temperature dependent. Furthermore, the metal ions actually kill the microorganisms, and other microorganism promoting bacteria and protozoa, rather than merely suppress them, as in the case of chlorine. This minimizes the possibility of later recolonization. Other advantages of metal ionization compared to other eradication techniques include relatively low cost, straightforward installation, easy maintenance, and the presence of residual disinfectant throughout the system.
A copper or silver ion generator is, by way of specific example, an effective method for controlling legionella which is likely to be present in most water systems. Legionella is predominantly present in water cooling systems in microbial biofilms which become attached to surfaces submerged in the aquatic environment. These biofilms are typically found on the surfaces of pipes and stagnant areas of the water cooling system. Many components of most any man-made water system can be considered to be an amplifier for the organism (i.e., the organism can find a niche where it can grow to higher levels, or be amplified) or a disseminator of the organism. Examples of man-made amplifiers include cooling towers and evaporative condensers, humidifiers, potable water heaters and holding tanks, and conduits containing stagnant water. Showerheads, faucet aerators, and whirlpool baths may serve as amplifiers as well as disseminators. Human infection from exposure to legionella, or legionosis, can result in a pneumonia illness that is commonly referred to as Legionnaire's disease, namesake of the famous 1976 outbreak in Philadelphia. Since that outbreak, about 1,400 cases are officially reported to the Center for Disease Control annually.
Other bacteria and protozoa can also colonize water cooling system surfaces and some have been shown to promote legionella replication. Amoebae and other ciliated protozoa are natural hosts for legionella. Legionella multiply intracellularly within amoebae trophozoites. Legionella pneumophila is known to infect five different genera of amoebae , most notably Hartmanella vermiformis and Acanthamoeba . Legionella can also multiply within the ciliated protozoa, Tetrahymena. Bacterial species that appear to provide legionella with growth-promoting factors include Pseudomonas, Acinetobactor, Flavobacterium, and Alcaligenes. Copper and silver ions are an effective method of control for each of these bacteria and protozoa. The controlled release of copper or silver ions has also been known to serve as an effective attachment and growth control for such marine organisms as algae, mussels, oysters and barnacles. Such ions can eliminate and control algae, for example, by inhibiting photosynthesis which leads to its demise.
In the experience of these inventors, users of present metal ion generators in industrial cooling water systems have reported problems such as bridging which leads to electrical shorting, electrical conductivity stratification which results in uneven electrode erosion, and plating of metal on the cathode. Bridging occurs because of the necessity of placing the anode and cathode in close proximity to one another in fresh water systems. One way of dealing with this problem is to periodically reverse polarity of the electrodes. Uneven electrode erosion due to electrical conductivity stratification occurs for the reason that nonuniform water flow occurs between electrodes. In present designs, the velocity of the water that flows between the electrodes is not generally constant over the electrode face. This leads to stratification of inorganic materials in the water that, in turn, produces electrical conductivity stratification. Finally, plating of the metal anode material on the cathode, as previously mentioned, completely defeats the purpose of the ion generator in the present application. When plating occurs, the metal ions are deposited on the cathode rather than being introduced into flow stream that is to be treated. In the experience of these inventors, each of these problems is related to water flow and to electrode spacing, which is required to be very close in fresh water systems. The spacing of the electrodes in close proximity to each other in fresh water systems is required if power system expectations are to be within reason, on the order of a few hundred watts. The system simply will not be economical if maximum power requirements exceed several kilowatts.
SUMMARY OF THE INVENTION
It is, therefore, a principal object of this invention to provide an improved method and apparatus for exposing the water flow within a water system to an ion generation device wherein water velocity is increased between the electrodes of the ion generator. It is another object of this invention to provide such an improved method and apparatus where a water inlet is provided to create a high velocity flow within the system, which flow is directed between the ion generating electrodes. It is yet another object to provide such an improved method and apparatus where a double vortex flow is created following water flow from between the electrodes. It is yet another object to provide such an improved method and apparatus which avoids “dead zones,” or areas where water velocities in the vicinity of the ion generator electrodes are low. It is still another object to provide such a method and apparatus in which a non-electrical conducting head is used to mount the electrodes of the ion generator and where a plurality of cooperatively alternating anodes and cathodes may be used. It is another object of the present invention to provide such an improved method and apparatus in which polarity of the electrodes is periodically reversed. It is yet another object of the present invention to provide such an improved method and apparatus in which a discharge valve is provided to control the system water level within the ion generator thereby maintaining a minimum vertical velocity within the system. It is still another object to provide a self-cleaning elliptical or conical base to the flow tank. It is yet another object to provide such an improved method and apparatus wherein a sight glass is utilized to allow for visual inspection of anode wastage. It is still another object to provide such an improved method and apparatus wherein performance is optimized while manufacturing costs are not increased significantly.
The present invention has obtained these objects. It overcomes problems and disadvantages of prior systems by providing an improved method and apparatus in which water flowing through a water system is vigorously and turbulently exposed to a plurality of electrodes of an ion generator whereby ions that are generated are fed into the water flow to prevent fouling of the water system by algae, nuisance invertebrates, microorganisms, and inorganic salts. The present invention accomplishes this by providing an ion generator having a self-contained tank through which the water flows. The generally cylindrical containment tank includes an inlet pipe at the uppermost portion of the tank. An elliptical tank base includes an outlet pipe in combination with a tank clean out device at the lowermost portion of the tank. A tank cover is provided which serves as the non-electrical conducting head for a plurality of electrodes that extend downwardly and generally parallel to one another from the underside of the cover. When the tank cover is in place in its normal operating position, the electrodes are suspended from the tank cover within the containment tank. The inlet pipe is functionally configured to introduce water directly between the electrodes. The electrodes are functionally configured, both in size, shape and placement, to maximize water flow between them, thereby creating a double vortex flow following water flow between the electrodes. Circuitry is provided to allow for periodic reversal of polarity of the electrodes. A sight glass is provided within the containment tank to allow for visualization and monitoring of the container contents, and in particular anode wastage or wear, during operation. The foregoing and other features of the improved method and apparatus of the present invention will be apparent from the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the improved water system fouling control apparatus constructed in accordance with the present invention.
FIG. 2 is a top plan view of the improved water system fouling control apparatus shown in FIG. 1 .
FIG. 3 is a partially sectioned front elevational view of the improved water system fouling control apparatus shown in FIG. 1 and taken along line 3 — 3 of FIG. 2 .
FIG. 4 is a front, top and right side perspective view of the improved water system fouling control apparatus shown in FIG. 3 .
DETAILED DESCRIPTION
Referring now to the drawings in detail, wherein like numerals represent like elements throughout, FIG. 1 illustrates a preferred embodiment of a device that utilizes the improved method and apparatus of the present invention.
An ion generator apparatus, generally identified 10 , includes a containment tank 12 that is generally cylindrical in physical configuration. The containment tank 12 includes an upper tank portion 14 and a lower tank portion 16 and is constructed of stainless steel in the preferred embodiment, although the material is not a limitation of this invention. The tank 12 also includes an upper tank portion aperture 15 and, situated about the perimeter of the upper tank portion aperture 15 , an upper tank flange 18 . The containment tank 12 is supported about its outer perimeter by a plurality of support legs 44 , each support leg 44 being attached to the tank 12 . Each leg 44 also includes a support foot 46 that rests upon a generally horizontal surface 88 . As shown in FIGS. 2 and 4 , three such legs 44 are illustrated. It is to be understood that more legs 44 could be utilized if such was desired or required, the number of such legs 44 not being a functional limitation of the present invention.
Attachable to the upper tank flange 18 is a tank cover or lid 20 . The lid 20 includes a lid perimeter 22 , a top lid surface 24 and a lid underside surface 26 . In the preferred embodiment, the lid 20 is constructed of a special polymar plastic material which provides strength, durability and electrical nonconductivity. The significance of this electrical nonconductive, or electrical insulating, feature will become apparent later in this detailed description. The lid 20 is attachable to the upper tank portion 14 by means of a plurality of fasteners 86 , such as bolts, which are installed about the lid perimeter 22 and through the upper tank flange 18 . See FIGS. 2 and 3 . Here again, the number of such fasteners 86 is not a functional limitation of the present invention. The number of fasteners 86 may be varied without deviating from the scope of this invention. The important feature of the fasteners 86 is that they prevent the lid 20 from coming away from the tank 12 and that they prevent rotation of the lid 20 about the tank 12 .
Sealingly attached to the lower tank portion 16 is an elliptical head 34 . The lowermost portion of the head 34 includes a centrally located bottom aperture 38 . Attached to the aperture 38 is a bottom flange 40 . Attached to the bottom flange 40 is an elbow 48 which includes a first flanged end 92 , a discharge sampling valve 94 , and a second end 96 . Attached to the second end 96 is a ball valve 97 , an inline flow meter 98 and a discharge pipe 99 through which tank discharge flow 8 is accomplished. The flow meter 98 may be wired to control inlet flow.
Attached to the underside 26 of the lid 20 are a number of functionally cooperating electrodes 50 , 60 . As shown in the preferred embodiment, one anode 50 and one cathode 60 is provided. It is to be understood that the number of such electrodes 50 , 60 is not a functional limitation of the present invention. Other combinations could be provided, such as two anodes and two cathodes, and so on, without deviating from the scope of the present invention. As shown, the anode 50 and the cathode 60 are each fabricated in the shape of a rectangular prism. To limit scaling and to provide for uniform electrode 50 , 60 wear, as previously described, the physical design and spacing of the electrodes 50 , 60 is, in the view of these inventors, critical to operation of ion generators that utilize the electrolysis process. Due to the nature of the electric field established between the electrodes 50 , 60 , optimum spacing and shape is dependent on the following factors:
1. Electrode Aspect Ratio; 2. Electrode Space Ratio; and 3. Electrode Edge Ratio.
The Electrode Aspect Ratio (or “AR”) can be defined as the length divided by the width of the electrode 50 , 60 . Electrode Space Ratio (or “ESR”) is defined as electrode width divided by the space between adjacent electrodes 50 , 60 . Electrode Edge Ratio (or “ER”) is defined by the edge radius of the electrode divided by electrode thickness. The combination of these ratios produces an electrode “shape factor” that must be maintained in order produce optimum performance in low conductivity electrolytes such as fresh water. The electrode shape factor (F) is defined by the following equation:
F=K (σ,β,)[( AR )×( ESR )×( ER )] y
wherein
K=Af(σ, β) of a first order Arrhenius type at the micro scale σ=Electrolyte conductivity β=Electrolyte Chemistry parameter AR=Aspect Ratio=1.0+/−5% ESR=Electrode Space Ratio=0.5+/−5% ER=Electrode Edge Ratio=0.5+/−5% Y=Form Factor Exponent=0.25 F=0.7+/−5%
In the preferred embodiment, the anode 50 is made of silver as is the cathode 60 . Again, the material from which each of the electrodes 50 , 60 is made is not a limitation of the present invention, other than that the materials used must be functionally conducive to the process of electrolysis. The use of like material for the electrodes 50 , 60 allows an electronic polarity reverser (not shown) to be used which reduces the rate of oxide buildup on the silver anode 50 which, in turn, reduces the time between scheduled anode cleanings.
The polarity reverser allows for maximum usable material of the same chemistry of the electrodes 50 , 60 to be located inside the ion generator containment tank 12 which results in longer intervals between electrode 50 , 60 change out. Since the electrode material is the same in each electrode, one electrode will be the anode 50 and the other the cathode 60 and then at a prescribed, predetermined time interval, the polarity will be reversed by the polarity reverser where the anode 50 becomes now the cathode 60 and the cathode 60 becomes the anode 50 and vice versa over time. This results in uniform depletion of the material of each electrode 50 , 60 . Time delays for the polarity reverser that have a wide range of variation between reversing polarity time intervals are specific for different water chemistry due to the low conductivity of the electrolytes.
The anode 50 includes a top anode portion 52 , a central anode portion 54 , a bottom anode portion 58 , and a pair of anode faces 56 , the anode faces 56 being generally parallel to one another and providing the greatest surface area of the anode 50 . Similarly, the cathode 60 includes a top cathode portion 62 , a central cathode portion 64 , a bottom cathode portion 68 , and a pair of cathode faces 66 . The anode 50 is attached to the lid underside 26 by means of a plurality of anode fasteners 102 . See FIG. 2 . Similarly, the cathode 60 is attached to the lid underside 26 by means of a plurality of cathode fasteners 104 . At the bottom portion 58 of the anode 50 and the bottom portion 68 of the cathode 60 is a stabilizing element 90 . The stabilizing element 90 is functionally adapted to maintain the electrodes 50 , 60 in substantially parallel planar relationship. In this parallel planar relation, the plane defined by each electrode 50 , 60 is substantially parallel to the axis of the inlet pipe 30 . See FIGS. 2 and 3 . As shown, one of the anode fasteners 102 is attached to a positive electrical lead 112 through which an electrical current may flow. Similarly, one of the cathode fasteners 104 is attached to the cathode 60 and is also attached to a negative, or grounding, lead 114 . An electrical potential or voltage may be applied across the anode lead 112 and the cathode lead 114 and, therefore, across the anode 50 and across the cathode 60 . In the preferred embodiment, a power supply on the order of several hundred watts may be applied to achieve the electrochemical process of electrolysis across the electrodes 50 , 60 .
The upper tank portion 14 also includes an inlet pipe 30 that provides a continuum with the interior 80 of the containment tank 12 . As shown, the flow path 2 through the inlet pipe 30 is generally perpendicular to the axis of the tank interior 80 . The tank 12 , the elliptical head 34 and the inlet pipe 30 are functionally cooperative to allow water flow 2 through the inlet 30 , into the tank interior 80 in a whirlpool-like or double vortex flow 4 , and out the bottom aperture 38 of the head 34 in a discharge flow 6 . See FIGS. 2 and 3 . The significance of this flow pattern will become apparent later in this detailed description. The containment tank 12 also includes a sight glass aperture (not shown) defined within the wall 13 of the tank 12 . Attached to the aperture is a sight glass flange 82 and a sight glass 84 . The purpose of the sight glass 84 is to provide visual access to the tank interior 80 .
In application, water flow 2 is initiated to the interior 80 of the tank 12 by means of an inlet pipe 30 . In this fashion, water enters the tank interior 80 and is directed to forcibly flow between the electrodes 50 , 60 . Upon exiting the area between the electrodes 50 , 60 , the water follows the annular wall surface 13 in a whirlpool-like or turbulent double vortex-type fashion. That is, the water flow is effectively “split” at that portion of the wall surface 13 immediately opposite the inlet and continues in two opposite directions back around the electrodes 50 , 60 and along the wall surface 13 . This double vortex turbulence facilitates the electrolysis process and the migration of silver ions away from the anode 50 and away from the cathode 60 before the ions have a chance to attach themselves to the cathode 60 thus defeating the purpose of ionic water treatment. The flow 4 continues about the electrodes 50 , 60 until the water flow 6 discharges through the head aperture 38 , the water being properly ionized at this point. The elliptical head 34 and the aperture 38 defined in it serves a “self-cleaning” function by discharging suspended solids contained within the flow stream 6 . The water ionization at this point of discharge serves to control algae, nuisance invertebrates, microorganisms and inorganic salts lurking in other parts of the water system within which the ion generator assembly 10 of the present invention is incorporated. As the electrolysis process continues, the electronic polarity reverser (not shown) cycles at reversing rates from 0.1 second to 1,000 minutes depending on rates of reversal deemed appropriate for a specific site operation. Gradually, the anode 50 effectively becomes used up as ions are given up to the water flow 4 . The sight glass 84 allows the user to view the containment tank interior 80 to determine if anode wastage has occurred to the point that the anode 50 must be replaced. Replacement of the anode 50 is easily accomplished by removal of the tank lid 20 , detachment of the anode lead 112 , withdrawal of the anode fasteners 102 , insertion of a new anode 50 , replacement of the anode fasteners 102 , reattachment of the anode lead 112 and reseating of the lid 20 .
From the foregoing description of the illustrative embodiment of the invention set forth herein, it will be apparent that there has been provided an improved method and apparatus for exposing the water flow within a water system to an ion generation device wherein water velocity is increased between the electrodes of the ion generator; where a perpendicular inlet is provided to create a high velocity vortex flow within the system in the vicinity of the ion generator electrodes and which avoids “dead zones,” or areas where water velocities in the vicinity of the ion generator electrodes are low; where a non-electrical conducting head is used to mount the electrodes of the ion generator and where a plurality of cooperatively alternating anodes and cathodes may be used; where a discharge valve is provided to control the system water level within the ion generator thereby maintaining a minimum vertical velocity within the system; where a self-cleaning elliptical or conical base to the flow tank is provided; and where a sight glass is utilized to allow for visual inspection of anode wastage. | A method and apparatus for turbulently exposing water flowing through a water system to a plurality of electrodes of an ion generator and having a self-contained tank through which water flows is provided with an inlet pipe that directs water flow between the electrodes. A tank cover serves as a non-electrical conducting head for the plurality of electrodes that extend downwardly from the underside of the cover. The electrodes are functionally configured to maximize water flow between them. Following the flow of water between the electrodes, a double vortex of water flow is created along one wall of the tank. A sight glass allows for visualization of the container contents, and in particular electrode wastage or wear, during operation. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a clothes dryer, and particularly, to a structure for a roller capable of supporting a drum inside a clothes dryer.
[0003] 2. Background of the Invention
[0004] Recently, a clothes dryer serves to dry an object to be dried by absorbing moisture inside the object by blowing blast generated by an electric heater or a gas heater into a drum. According to a method for processing humid air generated when drying the object, the clothes dryer is largely classified into an exhaustion-type clothes dryer and a condensation-type clothes dryer.
[0005] FIG. 1 is a view showing a clothes dryer in accordance with the conventional art.
[0006] Referring to FIG. 1 , the conventional clothes dryer comprises a body 10 that forms appearance, a drum 20 rotatably installed in the body 10 , a door 30 through which an object to be dried is introduced into the clothes dryer, etc. Although not shown, the conventional clothes dryer further comprises a circulation duct having both ends connected to the drum thus to form a flow path for air circulation; a heater disposed in the circulation duct for heating air; a blowing fan for forcibly circulating air; etc. The condensation-type clothes dryer comprises a heat exchanger for removing moisture included in air exhausted from the drum 20 .
[0007] The drum 20 is rotated by receiving a driving force, through a belt (not shown), from a motor (not shown) installed at an inner lower side of the body 10 . The clothes dryer requires a means configured to prevent the drum 20 to be downwardly deformed due to a load of laundry and a load of the drum 20 , and configured to support a lower side of the drum 20 for smooth rotation of the drum 20 . For this, a supporting roller 40 is generally installed below the drum 20 .
[0008] FIGS. 2 and 3 are perspective and sectional views of the supporting roller. Referring to FIGS. 2 and 3 , the supporting roller 40 of the drum 20 includes a roller shaft 41 ; a roller frame 42 slidably installed at the roller shaft 41 and rotated; a roller outer circumferential portion 43 formed of rubber having an elastic force to support the drum 20 , and attached to an outer circumference of the roller frame 42 ; a bearing 44 disposed between the roller frame 42 and the roller shaft 41 , and configured to allow the roller frame 42 to be smoothly rotated; and a triangular pin 45 configured to support the roller frame 42 at both sides so as to prevent the roller frame 42 from being separated from the roller shaft 41 .
[0009] The supporting roller 40 of the conventional clothes dryer is mounted to the roller shaft 41 by using an oil-less bearing formed between the roller frame 42 and the roller shaft 41 . However, when a load supported by the bearing increases, oil included in the oil-less bearing may be discharged out. This may degrade a lubricating characteristic of the supporting roller 40 , and may cause noise occurrence and damage of the supporting roller 40 . Especially, in the case of 24-inch clothes dryer rather than 27-inch clothes dryer, the above problems may become more severe due to a narrow inner space and an overload.
[0010] Furthermore, in the conventional bearing, the roller outer circumferential portion 43 contacting the drum 20 has a convexed portion at a central part thereof. This may cause only parts of the entire region of the roller outer circumferential portion 43 to contact the bearing. As a result, a stress applied to the supporting roller 40 is concentrated on specific regions, thereby shortening the lifespan of the supporting roller 40 .
SUMMARY OF THE INVENTION
[0011] Therefore, an object of the present invention is to provide a clothes dryer capable of providing a structure of a roller which supports a drum of the clothes dryer, the roller configured to endure even a large load applied thereto, capable of prolonging the lifespan of the roller by preventing stress concentration by increasing a contact area between the roller and the drum, and capable of enhancing the reliability.
[0012] To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; and a roller disposed below the drum, and configured to support the drum, wherein the roller is mounted to a roller shaft by a ball bearing.
[0013] When coupling the roller to the roller shaft, may be used a ball bearing, not the conventional oil-less bearing. This may enable the bearing of the roller shaft to have stronger endurance against thermal deformation or abrasion due to heat.
[0014] A stopping portion for mounting the ball bearing may be formed at the roller shaft.
[0015] A screw thread for nut mounting may be further formed at one side of the roller shaft, and a screw thread for fixing the roller into the clothes dryer may be formed at another side of the roller shaft. As a nut is mounted to the screw thread after mounting the roller to the roller shaft, the roller may be more stably mounted to the roller shaft.
[0016] A contact portion of the roller contacting the drum may be formed to be flat.
[0017] The roller may comprise a roller frame configured to insert the roller shaft; and an outer wheel portion mounted to the roller frame, and configured to encompass an outer circumferential surface of the roller frame.
[0018] Since the contact portion of the roller may be formed to be flat, a stress applied to the roller may be distributed to prolong the lifespan of the roller.
[0019] A plurality of concave-convex portions may be formed on an outer circumferential surface of the roller frame, and a plurality of concave-convex portions engaged with the concave-convex portions may be formed on an inner circumferential surface of the outer wheel portion. As the concave-convex portions of the roller frame may be coupled to the concave-convex portions formed on the inner circumferential surface of the outer wheel portion, the roller frame may be stably coupled to the outer wheel portion. The outer wheel portion of the roller may be formed of rubber having an elastic force.
[0020] Under these configurations, even when a large load may be applied to the roller, the roller may endure the load. This may prolong the lifespan of the roller that supports the drum, and enhance the reliability of the clothes dryer.
[0021] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
[0023] In the drawings:
[0024] FIG. 1 is a view showing a clothes dryer in accordance with the conventional art;
[0025] FIG. 2 is a perspective view of a roller of FIG. 1 ;
[0026] FIG. 3 is a sectional view of FIG. 2 ;
[0027] FIG. 4 is a sectional view of a roller which supports a drum of a clothes dryer according to the present invention; and
[0028] FIG. 5 is a perspective view of a roller shaft of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0029] Description will now be given in detail of the present invention, with reference to the accompanying drawings.
[0030] Hereinafter, a clothes dryer according to the present invention will be explained in more detail with reference to the attached drawings.
[0031] FIGS. 4 and 5 are views respectively showing a roller for supporting a drum of a clothes dryer according to the present invention.
[0032] The roller for supporting a drum of a clothes dryer according to the present invention is mounted to a roller shaft 51 by a ball bearing 53 . That is, in the present invention, the roller is provided with a ball bearing, not the conventional oil-less bearing. This may enable the bearing of the roller shaft 51 to have a stronger endurance against thermal deformation or abrasion due to heat.
[0033] The roller shaft 51 for mounting the roller is provided with a bearing mounting surface 51 e for mounting the ball bearing 53 . For stable mounting of the ball bearing 53 , a stopping portion 51 c having a diameter a little larger than that of the bearing mounting surface 51 e is disposed on a side surface of the bearing mounting surface 51 e. On the basis of the bearing mounting surface 51 e of the roller shaft 51 , a screw portion 51 a for mounting a nut 52 is formed at an opposite side to the stopping portion 51 c. A stepped portion 51 d may be formed between the screw portion 51 a and the bearing mounting surface 51 e, thereby showing the position of the nut coupled to the screw portion 51 a. After inserting the ball bearing 53 into the bearing mounting surface 51 e of the roller shaft 51 , the nut 52 is coupled to the screw portion 51 a. As the ball bearing 53 is disposed between the stopping portion 51 c and the nut 52 , the ball bearing 53 is prevented from being separated from the roller shaft 51 . That is, owing to the stopping portion 51 c and the nut 52 mounted to the screw portion 51 a, the ball bearing 53 can be easily and precisely mounted on the roller shaft 51 , and the ball bearing 53 can be prevented from being separated from the roller shaft 51 .
[0034] At one side of the roller shaft 51 , the ball bearing 53 is mounted. And, another side of the roller shaft 51 is mounted to a fixing member 61 inside the clothes dryer. For this, a screw thread 51 b is formed at another side of the roller shaft 51 . The roller shaft 51 is inserted into the fixing member 61 inside the clothes dryer, and a nut 60 are coupled to the screw thread 51 b, thereby fixing the roller shaft 51 to a predetermined position inside the clothes dryer.
[0035] An outer circumferential surface of the roller, i.e., a contact portion contacting the drum is formed to be flat. This may enable a contact surface of the roller contacting the drum to have a wider area. Therefore, a stress applied to the outer circumferential surface of the roller decreases to prolong the lifespan of the roller.
[0036] Preferably, the roller includes a roller frame 54 configured to insert the roller shaft 51 therein by using the ball bearing 53 ; and an outer wheel portion 55 mounted to the roller frame 54 , and configured to encompass an outer circumferential surface of the roller frame 54 . In this case, an outer circumferential surface 55 a of the outer wheel portion 55 directly contacting the drum is formed to be flat thus to have a wider contact area. As the contact portion of the outer circumferential surface 55 a contacting the drum is formed to be flat, the stress applied to the roller is distributed to prolong the lifespan of the roller.
[0037] A plurality of concave-convex portions are formed on an outer circumferential surface of the roller frame 54 , and a plurality of concave-convex portions engaged with the concave-convex portions are formed on an inner circumferential surface of the outer wheel portion 55 . As the concave-convex portions of the roller frame 54 are coupled to the concave-convex portions formed on the inner circumferential surface of the outer wheel portion 55 , the roller frame 54 can be stably coupled to the outer wheel portion 55 . The outer wheel portion 55 of the roller is preferably formed of rubber having an elastic force.
[0038] The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.
[0039] As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims. | Disclosed is a clothes dryer comprising a drum rotatably disposed in a body; and a roller disposed below the drum, and configured to support the drum. The roller is mounted to a roller shaft by a ball bearing, and a contact portion of an outer circumferential surface of the roller contacting the drum is formed to be flat. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to an automatic equalization apparatus for a recording system or a transmission system, and in particular to an automatic equalization method, and apparatus attaining high-speed, high-precision operation with simple configuration.
In order to prevent occurrence of intersymbol interference in a digital information train having a period T, its impulse response h(t) must, in general, satisfy the so-called Nyquist condition with the Nyquist frequency equivalent to 1/2T. That is to say, the following relations must be satisfied at time nT. ##EQU1##
An automatic equalizer automatically sets tap coefficients of a transversal filter so that the impulse response reproduced from a VTR, a disk or the like may satisfy equation (1). A so-called zero forcing algorithm is included in basic algorithms of automatic equalization as described in, for example, U.S. Pat. No. 3,414,845 issued on Dec. 3, 1968 to R. W. Lucky. An example of an apparatus based upon this scheme is shown in FIG. 2. By referring to FIG. 2, operation of this algorithm will now be described briefly and at the same time problems of this scheme will be made clear.
As shown in FIG. 2, a transversal filter typically comprises delay lines 1 and 2, gain adjusting circuits 3, 4 and 5, and an adder 6. It is now assumed that each gain adjusting circuit has a coefficient Cj. Assuming now that the impulse response from the information source to the equalizer output is h(t), the sum D of absolute values of intersymbol interference obtained after equalization is given by the following equation. ##EQU2##
In the zero forcing algorithm, the gain of the transversal filter is so controlled that the value of D may be minimized. Assuming now that the pulse train supplied from the information source has a value a k (where a k is a binary valued signal comprising "1" or "0") at time kT, the output of the adder 6 at time kT is given by the following equation. ##EQU3##
A signal e k corresponding to an equalization error is given by the following equation.
e.sub.k =y.sub.k -a.sub.k ' (4)
Character a k ' represents a value obtained by identifying and reproducing y k in a comparator 7 of FIG. 2 and coincides with a k in the absence of a code error. Character e k denotes an output of a comparator 8. By using the above described a k ' and e k , evaluation function H j of equalization error is given by ##EQU4## where m is a value depending upon the signal-to-noise ratio (SN ratio) and is typically in a range 10 3 <m<10 4 .
The value of H j is derived by using a computer 10 shown in FIG. 2. By increasing the coefficient C j of the gain adjusting circuit by a minimum amount Δ when H j is positive and by decreasing the coefficient C j by the minimum amount Δ when H j is negative, the intersymbol interference D represented by equation (2) is reduced. If input data comprises a train in which "1" or "0" appears randomly, automatic equalization is attained by the zero forcing algorithm heretofore described.
The above described equalizer basically has two problems described below.
(1) In the configuration shown in FIG. 2, the main line signal which becomes the reference of H j passes through the gain adjusting circuit 4. Therefore, the gain adjusting circuit must be high in precision. Especially in a reproduced signal of a digital VTR, an amplitude variation having a high frequency component caused by defective contact between the tape and the head is incurred. For such a signal, gain adjusting circuits which are rapid in response speed become necessary. Further, since high-speed pulses of 100 Mbps or more are recorded onto/reproduced from the digital VTR, gain adjusting circuits having wide bandwidth become necessary. It is extremely difficult to realize gain adjusting circuits satisfying all of the conditions heretofore described.
(2) In addition, calculation of equation (5) must be executed at a speed of 100 Mbps in the above described equalizer configuration. Calculation of equation (5) is performed with respect to a series of m pulses depending upon the signal-to-noise ratio. Since dropouts often occur in the recording/reproducing system, however, a serious error is caused in the calculation result if pulses are missed consecutively.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a high-speed, high-precision automatic equalization method, and apparatus.
According to one aspect of the present invention, an output signal of a transversal filter is simultaneously supplied to two juxtaposed comparators, signal identification in one of the two comparators is performed, an equalization error is detected in the other of the two comparators with the reference level thereof changed, data from resultant two kinds of data trains are extracted by taking at least (N-1)/2+1 bits as the unit, N being the number of taps of the transversal filter, correlation computation is performed therewith, and tap coefficients of the transversal filter are set on the basis of the resultant accumulated value. By such configuration, only the equalization error generated in the recording/reproducing system can be detected with extremely high precision without exerting any influence of the gain adjusting circuit upon the main line signal, thereby automatic equalization being made possible.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a configuration diagram of an embodiment of an automatic equalization apparatus according to the present invention.
FIG. 2 is a configuration diagram of an automatic equalization apparatus of the prior art.
FIGS. 3A and 3B are operation waveform diagrams of the automatic equalization apparatus according to the present invention.
FIG. 4 is an auxiliary diagram showing operation of the automatic equalization apparatus according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an embodiment of an automatic equalization apparatus according to the present invention. In accordance with the present invention, the gain adjusting circuit 4 of the prior art is not used, and the main line signal outputted by the delay line 1 is directly supplied to the adder 6. Thereafter, the output of the adder 6 is supplied simultaneously to two comparators, where its amplitude undergoes binary decision. As represented by "threshold for demodulation" of FIG. 3A, the comparator 7 has a threshold set at an intermediate level between amplitudes respectively corresponding to "1" and "0". In the absence of an error, therefore, the output of the comparator 7 corresponds to the original data. On the other hand, the comparator 8 is provided, as its reference level, with a threshold higher than that of the comparator 7 or a threshold lower than that of the comparator 7 to convert the output of the adder 6 into a binary value. FIG. 3B shows an example of a higher threshold. The equalization error e k represented by equation (4) can be obtained at the output of the comparator 8 by making +1 correspond to "1" of the signal a k ' as the higher threshold and making -1 correspond to the amplitude of "0" as the lower threshold. For this purpose, the value of H j expressed by equation (5) is rewritten as represented by the following equation. ##EQU5##
The former half (the second line) of equation (6) represents an equalization error obtained when the signal a k ' is "1", whereas the latter half (the third line) of equation (6) represents an equalization error obtained when the signal a k ' is "0". Since a waveform obtained when a k ' is "1" and that obtained when a k ' is "0" are typically symmetrical, the equalization error H j can be calculated by using only one of the former half and the latter half. In the recording/reproducing system, however, the waveform of "1" often differs from that of "0" because of occurrence of nonlinear distortion. In this case, it is possible to derive values of H j for both the former half and the latter half and use the average of the results. H j is calculated in accordance with equation (5) by using the computer 10. In response to that result, the output value of a D/A converter 11 is increased or decreased. The threshold of the comparator 8 is thus controlled to become a required amplitude value of a k '. By thus changing the threshold of the comparator 8, the function of the gain adjusting circuit 4 can be equivalently realized. At the present time, a D/A converter having 10 or more bits as the number of quantization bits and capable of operating at a frequency of 10 MHz or higher is already available on the market. By using such a D/A converter, only the equalization error generated in the recording/reproducing system can be detected with extremely high precision without exerting any influence of the gain adjusting circuit upon the main line signal, automatic equalization being made possible. As a result, the above described first problem is eliminated.
A method for eliminating the second problem will now be described by referring to the embodiment. The number of taps of a transversal filter is practically limited. Assuming now that the number of taps is 3 as an example, a concrete example will be hereafter described. It is now assumed that the equalization error of each tap coefficient is detected by using only the former half shown in the second line of equation (6). Evaluation values H j for controlling respective tap coefficients are given by the following equation. ##EQU6##
Letting n=1, this equation coincides with the former half of equation (6). However, there is not the necessity that n=1. Considering now H 1 as an example, the value of H 1 can be derived if there is a train of adjacent a' k and e k . This fact similarly holds true for H -1 and H 0 as well. To facilitate understanding, H 1 in equation (7) will now be concretely calculated in accordance with FIGS. 3A and 3B. The waveform shown in FIGS. 3A and 3B is obtained when intersymbol interference as shown in FIG. 4 appears in an isolated waveform. For brevity of description, it is now assumed that values such as (a, b), (b, c), (c, d),--(h, i) as shown in FIGS. 3A and 3B are obtained as a result of sampling at intervals of n bits. In this case, identified data of FIG. 3A becomes "1" at time b, d, e and h, and e k is obtained from identified data of FIG. 3B. Therefore, H 1 is represented by the following equation. ##EQU7##
That is to say, the tap coefficient C 1 of the equalizer must be increased by Δ so as to decrease the intersymbol interference. This holds true for other equations as well. Assuming now that the number of taps of the transversal filter is N, it is evident from this example that evaluated values required for respective tap coefficients are obtained by extracting adjacent data comprising at least (N-1)/2+1 bits respectively from trains of a' k and e k and performing correlation computation. Therefore, influence of dropout in the recording/reproducing system can be avoided by choosing n so as to satisfy the relation n>>1. The operation heretofore described may be specifically carried out by frequency-dividing the output of a clock generator 9 by n at a frequency divider 14, supplying the resultant clock signal from the frequency divider 14 to gate circuits 12 and 13, extracting a data of a predetermined number of successive bits (a predetermined length of data) at intervals of n bits, and deriving respective evaluation values in the computer 10 by using the data thus extracted. The automatic equalization apparatus according to the present invention heretofore described operates if the data train to be handled is random.
As heretofore described, the present invention makes it possible to obtain a high-speed, high-precision automatic equalization method, and apparatus having simple configuration which can be applied to a recording system or a transmission system. | An automatic equalization apparatus useful for supplying an output signal of a transversal filter simultaneously to two juxtaposed comparators, one of the two comparators performing signal identification, the other of the two comparators detecting an equalization error with the reference level changed, and extracting data from resultant two kinds of data trains by taking at least (N-1)/2+1 bits as the unit, N being the number of taps of the transversal filter, performing correlation computation, and setting tap coefficients of the transversal filter on the basis of the resultant accumulated value. | 6 |
FIELD OF THE INVENTION
The present invention relates to a process for producing human-specific interferon (abbreviated as "HuIFN" hereinafter) using whole human blood and to a method for assaying the HuIFN productivity of human blood.
DESCRIPTION OF THE PRIOR ART
In recent years, clinical tests whereby the level of a blood enzyme or its metabolite is determined chemically have been in a wide use.
Since HuIFN, a blood component, exhibits antiviral- and antitumor activities, it has been proposed to include the level of serum HuIFN in the items of clinical test. Such proposal, however, has not been realized because serum HuIFN is minute.
Blood consists of a fluid, plasma, in which are suspended formed elements such as erythrocyte, leukocyte and platelet. One mm 3 blood generally contains, in addition to 7.4×10 3 leukocytes and 3×10 5 platelets in adult, 5.4×10 6 erythrocytes in man or 4.8×10 6 in woman.
It is well known that HuIFN is produced by human leukocytes.
In conventional processes to produce HuIFN, viable leukocytes separated from human blood are used. For example, as is evident from Hans Strander and Kari Cantell, Ann. Med. Exp. Fenn., Vol. 44, pp. 265-273 (1966), and the specifications of Japan Patent Kokai Nos. 6,111/74 and 94,008/78, leukocytes are separated from other elements present in whole blood, and then allowed to produce HuIFN.
Detailed studies on these conventional processes confirmed that they, however, give a low recovery yield of leukocytes from blood, i.e. 30-50%, and damage leukocytes during the separation to lower the viability to 40-60% and, eventually, the overall recovery yield to 10-30%, as well as that the separated leukocytes give an inconsistent HuIFN production, these facts render the estimation of the HuIFN productivity of blood very difficult, and cause an obstacle in mass-production of HuIFN.
DETAILED DESCRIPTION OF THE INVENTION
As the result of his research into the mass-production of HuIFN using precious human blood, as well as for the assay of the HuIFN productivity by use of donated blood, the present inventor eventually found that a large amount of HuIFN can be readily produced with an ease by incubating a whole blood sample in a vessel while exposing the whole blood to an anticoagulant and a virus. The present inventor also found that the HuIFN productivity of whole blood can be readily determined with high reproducibility by incubating whole blood in a vessel while exposing the whole blood to an anticoagulant and a virus, and titrating the accumulated HuIFN.
Detailed studies have confirmed that the exposure to an intact or inactivated virus of an amount of 20-200,000 HA/ml whole blood is favorable. "HA" represents the unit of the haemagglutination titer of a virus.
The wording of "whole blood" means fresh blood preparations collected from donors, and also suspensions which are obtained by removing plasma liquid from such blood preparations and suspending the residual formed elements in an suitable non-plasma liquid, e.g. physiological saline, buffer solution or nutrient culture medium.
Any anticoagulant capable of preventing the coagulation of such whole blood and does not affect HuIFN production is usable in the invention. For example, heparin, acid citrate-dextrose (ACD) and citrate-phosphate-dextrose (CPD) are favorable.
The viruses usable in the invention are those which are capable of inducing HuIFN production in the whole blood. For example, Sendai virus or Newcastle disease virus may be used intact or after inactivation. The inactivated viruses usable in the invention include those whose reproductivities are partially or completely suppressed, for example, by uv-irradiation, heating or treatment at an extreme pH. An appropriate range for inoculum of the virus is 20-20,000 HA/ml whole blood.
The step of incubating the whole blood in a vessel while exposing the whole blood to the anticoagulant and virus is carried out in such a manner that the whole blood is exposed in the vessel to the anticoagulant and virus to produce HuIFN. For example, to the prescribed amounts of the anticoagulant and virus in the vessel is added an appropriate amount of the whole blood, and the mixture is incubated therein. Alternatively, a mixture of the anticoagulant and whole blood is placed in a vessel, added with the virus, and incubated. In this incubation step, a suitable medium, e.g. physiological saline, isotonic buffer solution or nutrient culture medium, may be used additionally.
Tank, jar, flask, test tube, ampule and micro plate well of any shape and volume may be used as the vessel in the invention.
The incubation conditions are those under which HuIFN is producible: for example, temperature range of 30°-40° C.; and incubation time, 5-50 hours. In this case, priming or superinduction may be carried out if necessary.
After incubation to produce HuIFN and an optional dilution with physiological saline or isotonic buffer solution, the whole blood is then separated with suitable procedure(s), such as centrifugation or filtration, to remove formed elements such as blood cells, and the resultant supernatant or filtrate containing HuIFN is subjected to purification or titration.
The HuIFN can be purified to obtain an HuIFN preparation having the highest possible purity by combination of conventional procedures, e.g. salting-out, dialysis, filtration, concentration, adsorption and desorption by ion exchange, gel filtration, affinity chromatography using a suitable ligand such as antibody, isoelectric point fractionation and electrophoresis.
The obtained HuIFN is advantageously feasible as injection or drug for external or internal use in the prevention and treatment of human diseases, alone or in combination with one or more other substances.
The HuIFN productivity of human whole blood can be determined according to the invention by titrating the HuIFN level in the above described supernatant or filtrate. For the purpose of such titration, any assay can be used as long as the HuIFN production by the whole blood is titrated therewith; e.g. bioassay, radioimmunoassay and enzyme-linked immunosorbent assay.
In recent years, enzyme-linked immunosorbent assay has been developed as a highly safe, convenient and speedy assay. Any enzyme-linked immunosorbent assay capable of titrating IFN as the antigen is employable in the invention. For example, double antibody sandwich technique and modified double antibody sandwich technique are favorable.
It was confirmed that the HuIFN productivities determined in this way are very useful for clinically testing the individual donor.
The method according to the invention confirmed that the blood collected from a cancer patient is much lower in blood HuIFN productivity than those collected from healthy volunteers.
The following experiments further explain the present invention.
EXPERIMENT 1
Effect of Pretreatment on the HuIFN Productivity of Blood
The effect of pretreating blood on the productivity of HuIFN was studied. In this Experiment, fresh blood samples from three volunteers were used after heparinization.
The treated bloods used in this Experiment were as follows: a plasma-free suspension, obtained by centrifuging blood to remove plasma liquid and suspending the residual formed elements in RPMI 1640 medium to give the same element density as that in blood; and an ammonium chloride-treated suspension, obtained by treating blood with Tris-Hcl buffer (pH 7.2) containing 0.75% ammonium chloride in usual way to effect the haemolysis of the erythrocytes, centrifuging the mixture and suspending the resultant erythrocyte-free formed elements in RPMI 1640 medium to give the same element density as that in blood.
One ml aliquots of the heparinized or treated blood were placed in different plastic test tubes which were then added wih 0.1 ml aliquots of physiological saline containing Sendai virus in respective amount of 0, 100, or 1,000 HA, followed by 16-hour incubation at 37° C. The incubated mixtures were uv-irradiated to completely inactivate the Sendai virus, and centrifuged to obtain supernatants which were then assayed for HuIFN titers per ml whole blood.
The HuIFN titer was determined by the dye uptake assay reported in Anne L. R. Pidot, Applied Microbiology, Vol. 22, No. 4, pp. 671-677 (1971). The haemagglutination titer (HA) was determined by the method as reported by J. E. Salk, The Journal of Immunology, Vol. 49, pp. 87-98 (1944) with slight modification.
The results are given in Table 1.
As is evident from these results, the whole blood and plasma-free suspension containing the whole formed elements of blood are favorable for assaying the HuIFN productivity because of its high and consistent HuIFN productivity. It was also confirmed that the ammonium chloride-treated suspension wherein the erythrocytes were haemolyzed and removed gives a low and inconsistent HuIFN productivity.
TABLE 1______________________________________ Sendai virus Healthy volunteerTreatment (HA) A B C______________________________________No treatment 0 30 60 10 100 3,800 2,500 4,200 1,000 3,700 2,600 4,500Plasma-free 0 0 10 0suspension 100 3,600 2,400 4,600 1,000 4,100 2,800 4,200Ammonium chloride- 0 0 10 0treated suspension 100 0 200 100 1,000 0 300 70______________________________________
EXPERIMENT 2
Effect of Virus Inoculum on the Productivity of HuIFN
The effect of virus inoculum on the productivity of HuIFN was studied. Fresh blood samples from three healthy volunteers and two cancer patients were used after heparinization.
According to the method as described in Experiment 1, 1 ml aliquots of either heparinized blood sample were placed in different test tubes, added with 0.1 ml aliquots of physiological saline containing Sendai virus in respective amount of 0, 2, 20, 200, 2,000, 20,000, or 200,000 HA, incubated, and assayed for HuIFN titers per ml blood.
A series of experiments using 2,000,000 HA Sendai virus per ml blood was scheduled, but not done because preparation of such a high-titer Sendai virus was unsuccessful.
The results are given in Table 2.
TABLE 2______________________________________Sendai virus Healthy volunteer Cancer patient(HA) D E F G H______________________________________0 50 80 20 10 02 130 70 30 10 020 2,600 1,600 5,400 10 30200 2,800 2,400 5,800 20 702,000 4,100 2,100 6,300 20 19020,000 3,500 2,300 8,800 10 140200,000 4,400 2,200 7,300 10 1802,000,000 ND ND ND ND ND______________________________________ Note: ND means not done.
As is evident from these results, virus inocula in the range of 20-200,000 HA/ml blood are favorable.
It was confirmed that the blood collected from a cancer patient is much lower in blood HuIFN productivity than those collected from healthy volunteers. This suggests that the assay of blood HuIFN productivity is helpful for the detection of cancer in its early stage.
Several embodiments of the present invention are disclosed hereinafter.
PRODUCTION OF HuIFN
EXAMPLE 1
One ml of a heparinized fresh blood from a healthy volunteer was placed in a plastic test tube, added with 1,000 HA of Sendai virus, incubated at 37° C. for 20 hours, and uv-irradiated to completely inactivate the virus. After centrifuging the mixture, the resultant supernatant was assayed for HuIFN titer.
The HuIFN production was about 3,600 units per ml blood.
EXAMPLE 2
One ml of a heparinized fresh blood from a healthy volunteer was added with 2,000 HA of Newcastle disease virus wherein 90% of the reproductivity has been inactivated. After incubating at 37° C. for 15 hours, the mixture was assayed for HuIFN titer similarly as in Example 1.
The HuIFN production was about 2,800 units per ml blood.
EXAMPLE 3
A heparinized fresh blood from healthy volunteers was centrifuged to remove plasma. The formed elements so obtained were then centrifugally washed in physiological saline, and suspended in RPMI 1640 medium to give the same element density as that in blood.
The resultant suspension was placed in a mini jar, and added wih 500 HA of Sendai virus per ml suspension. After incubating at 37° C. for 16 hours, the mixture was treated and assayed for HuIFN titer similarly as in Example 1.
The HuIFN production was about 3,000 units per ml blood.
EXAMPLE 4
A suspension containing the formed blood elements was prepared similarly as in Example 3.
The suspension was placed in a mini jar, added with 300 units of HuIFN per ml suspension, and incubated at 37° C. for 6 hours. Thereafter, the suspension was further added with 1,000 HA of Sendai virus per ml suspension, and incubated at 37° C. for additional 16 hours. The resultant was treated and assayed for HuIFN similarly as in Example 1.
The HuIFN production was about 27,000 units per ml blood.
ASSAY OF BLOOD HuIFN PRODUCTIVITY
EXAMPLE 5
One ml of a heparinized fresh blood from a healthy volunteer, 28-year old man, was treated similarly as in Example 1, and subjected to bioassay for HuIFN titration.
The HuIFN productivity was about 3,600 units per ml blood.
EXAMPLE 6
One ml of a heparinized fresh blood from a healthy volunteer, 33-year old woman, was treated similarly as in Example 2, and assayed for HuIFN titration similarly as in Example 5.
The HuIFN productivity was about 2,800 units per ml blood.
EXAMPLE 7
A heparinized fresh blood from a healthy volunteer, 61-year old man, was treated similarly as in Example 3 to obtain a suspension containing the formed blood elements.
One ml of the suspension was placed in a plastic test tube, and added with 1,000 HA of Sendai virus. After incubating at 37° C. for 16 hours, the mixture was subjected to double antibody sandwich technique, an enzyme-linked immunosorbent assay, for HuIFN titration.
The HuIFN productivity was about 3,400 units per ml blood. This value was consistent with that obtained by bioassay.
EXAMPLE 8
A heparinized fresh blood from a cancer patient, 68-year old man, was treated similarly as in Example 5 to obtain an HuIFN productivity of about 140 units per ml blood.
EXAMPLE 9
A heparinized fresh blood from a cancer patient, 55-year old woman, was treated similarly as in Example 5 to obtain an HuIFN productivity of about 70 units per ml blood.
It will be obvious to those skilled in the art that various changes and alterations may be made without departing from the scope of the invention and the invention is not to be considered limited to what is described in the specification. | A process for producing HuIFN using whole human blood and a method for assaying the blood interferon (HuIFN) productivity are disclosed. The whole blood is incubated in the presence of an anticoagulant (e.g. heparin, ACD, and CPD) and a viral inducer under the conditions appropriate to accumulate a substantial amount of HuIFN. The blood HuIFN productivity determined by titrating the accumulated HuIFN with a suitable procedure (bioassay, radioimmunoassay, or enzyme-linked immunosorbent assay) is useful in clinical test to detect cancer in its early stage. The HuIFN per se is recovered, and purified prior to its prophylactic and therapeutic uses. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Korean Patent Application No. 10-2013-0118074, filed on Oct. 2, 2013 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] Apparatuses and methods consistent with exemplary embodiments relate to a display apparatus and a control method thereof, and more particularly, to a display apparatus and a control method thereof, in which the brightness of a screen is adjusted in consideration of an external light source reflected on the screen.
[0004] 2. Description of the Related Art
[0005] With development of technology, a television (TV), a monitor, a portable terminal and/or other similar display apparatuses now support various functions such as Web surfing, games, photographing of a still image or a moving image, etc. as well as a basic function of displaying an image. In particular, functions such as photographing, video calling, games, etc. are available in a display apparatus with a detachable camera or a built-in camera.
[0006] Besides the foregoing functions, the camera provided in the display apparatus senses ambient light of the display apparatus in order to adjust the brightness of an image displayed on a display. For example, if the ambient light of the display apparatus is bright, the image displayed on the display may be brightened so that a viewer can view a more vivid image. On the other hand, if there is little ambient light, the image displayed on the display may be dimmed so that power consumption of the display apparatus can be reduced to conserve energy.
[0007] However, if a fluorescent lamp, a desk lamp, the sun and/or other external light source are regularly reflected from a screen of the display, that is, if the external light source appears on the screen, an image on the screen may be blurred. In this case, the display apparatus with the foregoing function takes only its ambient brightness into account without considering the light of the external light source reflected from a certain region of the screen of the display in order to adjust the brightness of the entire image displayed on the display. This reflected light appears at the certain region of the screen in accordance with a viewing position of a user, and thus obscures the image displayed at that region, thereby deteriorating visibility. Further, if the intensity of light from the external light source is very strong, a user may be dazzled by the reflected light. To address this problem, a user has to inconveniently and manually adjust the brightness or change the settings of the image displayed on the display.
SUMMARY
[0008] One or more exemplary embodiments provide a display apparatus and a control method thereof, in which reflection of an external light source from a screen of a display is taken into account to adjust a setting of an image in a certain region on the screen, thereby improving visibility of a user.
[0009] According to an aspect of an exemplary embodiment, there is provided a display apparatus including: a display which comprises a screen for displaying an image thereon; a camera which captures an image of a region in front of the display; and a controller which determines a reflection region of the screen where a degree of reflecting light of an external light source at a viewing position of a user is greater than or equal to a predetermined value based on the image of the region in front of the display, and controls a brightness of the image in the reflection region of the screen to be greater than a brightness of the image in another region of the screen.
[0010] The controller may be configured to determine the reflection region by measuring a distance between the user and the display based on the image of the region in front of the display.
[0011] The controller may be configured to control a contrast value of the image in the reflection region of the screen to be greater than a contrast value of the image in the other region of the screen.
[0012] The controller may be configured to control an edge enhancement value of the image in the reflection region of the screen to be greater than an edge enhancement value of the image in the other region of the screen.
[0013] The camera may be configured to measure an intensity of light emitted from the external light source, and the controller may be configured to control a brightness of the image in the reflection region of the screen in accordance with the measured intensity of the light.
[0014] The controller may be configured to control a contrast value of the image in the reflection region of the screen to be greater than a contrast value of the image in the other region of the screen if the measured intensity of light is greater than or equal to a predetermined value.
[0015] The controller may be configured to control an edge enhancement value of the image in the reflection region of the screen to be greater than an edge enhancement value of the image in the other region of the screen if the measured intensity of light is greater than or equal to a predetermined value.
[0016] The controller may be configured to control brightness of an entire area of the image of the screen to be greater than a brightness of a setup image if both the user and the external light source are reflected on the image of the region in front of the display.
[0017] According to an aspect of another exemplary embodiment, there is provided a method of controlling a display apparatus comprising: capturing an image of a region in front of a display by using a camera; determining a reflection region of a screen of the display where a degree of reflecting light of an external light source at a viewing position of a user is greater than or equal to a predetermined value based on the image of the region in the front of the display; and controlling a brightness of the image in the reflection region of the screen to be greater than a brightness of the image in another region of the screen.
[0018] The determining the reflection region of the screen may comprise: measuring a distance between the user and the display based on the image of the region in front of the display; and determining the reflection region of the screen based on the measured distance.
[0019] The method may be provided further comprising: controlling a contrast value of the image in the reflection region of the screen to be greater than a contrast value of the image in the other region of the screen.
[0020] The method may be provided further comprising: controlling an edge enhancement value of the image in the reflection region of the screen to be greater than an edge enhancement value of the image in the other region of the screen.
[0021] The method may be provided further comprising: measuring intensity of light emitted from the external light source by using the camera; and controlling a brightness of the image in the reflection region of the screen in accordance with the measured intensity of the light.
[0022] The method may be provided further comprising: controlling a contrast value of the image in the reflection region of the screen to be greater than a contrast value of the image in the other region of the screen if the measured intensity of the light is greater than or equal to a predetermined value.
[0023] The method may be provided further comprising: controlling an edge enhancement value of the image in the reflection region of the screen to be greater than an edge enhancement value of the image in the other region of the screen if the measured intensity of the light is greater than or equal to a predetermined value.
[0024] The method may be provided further comprising: controlling a brightness of an entire area of the image of the screen to be greater than a brightness of a setup image if both the user and the external light source are reflected on the image of the region in front of the display.
[0025] According to an aspect of another exemplary embodiment, there is provided a non-transitory computer readable medium comprising computer executable instructions that cause a computer to perform: capturing an image of an area in front of a display; determining a region of the display where a light reflected by the display at a viewing position of a user is greater than or equal to a predetermined value based on the captured image; and increasing a brightness of the determined region of the display to be greater than a brightness of another region of the display.
[0026] The non-transitory computer readable medium may further include computer executable instructions that cause the computer to perform: measuring a distance between the user and the display using the captured image. The region of the display where the light reflected by the display at the viewing position of the user is greater than or equal to the predetermined value may be determined based on the measured distance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and/or other aspects will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings, in which:
[0028] FIG. 1 is a block diagram schematically showing a display apparatus according to an exemplary embodiment;
[0029] FIG. 2 illustrates a use state schematically showing a display apparatus according to an exemplary embodiment;
[0030] FIGS. 3 to 6 schematically show methods of determining a reflection region in the display apparatus according to exemplary embodiments; and
[0031] FIGS. 7 and 8 are schematic flowcharts of controlling the display apparatus according to exemplary embodiments.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0032] Below, a display apparatus and a control method thereof according to exemplary embodiments will be described in detail with reference to accompanying drawings.
[0033] FIG. 1 is a block diagram schematically showing a display apparatus 1 according to an exemplary embodiment;
[0034] As shown in FIG. 1 , a display apparatus 1 in this exemplary embodiment includes a camera 10 which photographs or captures a moving image/a still image of an external environment, a communicator 20 which transmits and receives data or the like to and from an exterior, an image processor 30 which processes an image signal to display a received image, a display 40 which displays an image, a controller 50 which controls operations of the display apparatus 1 , and a storage 60 which stores predetermined data.
[0035] In this exemplary embodiment, the display apparatus may include any device, which can process an image signal/image data and display it, such as a TV, a monitor for a computer, a portable multimedia player, a mobile phone, etc. to which the camera 10 is detachably connected or internally provided. However, the exemplary embodiments are not limited thereto.
[0036] The camera 10 may be detachably connected to or internally provided in the display apparatus 1 . Further, the camera 10 senses and photographs external environments of the display apparatus 1 .
[0037] The camera 10 may monitor the external environments for a predetermined period of time or at predetermined time intervals, and acquire an image by photographing a front region of the display 40 (hereinafter, referred to as a ‘photographed image’). For example, if it is sensed that a user and an external light source are located in front of the display apparatus 1 , the camera 10 informs the controller 50 that the user and the external light source are sensed, and photographs the sensed user and external light source, thereby transmitting the photographed image to the controller 50 . Also, the camera 10 senses an intensity of light from the external light source and transmits it to the controller 50 .
[0038] The communicator 20 may not only include elements for receiving a signal/data from an external input, but also further include various additional elements such as a wireless communication module (not shown) for wireless communication, a tuner (not shown) for tuning to a broadcasting signal, etc. in accordance with designs of the display apparatus 1 . In addition to receiving a signal from an external device, the communicator 20 may transmit information/data/signals of an image processing apparatus to the external device. That is, the communicator 20 is not limited to receiving a signal from the external device, and may be an interface for interactive communication. Further, the communicator 20 may include a communication module for short range wireless communication such as Bluetooth, infrared (IR), ultra wideband (UWB), Zigbee, etc., and may further include a communication port for wired communication.
[0039] The communicator 20 may transmit image data photographed by the camera 10 to the controller 50 , and send a command signal for controlling the camera 10 from the controller 50 to the camera 10 , if the camera 10 is detachably provided in the display apparatus 1 .
[0040] The image processor 30 processes an image signal, received through the communicator 20 , to be displayed as an image. The image processor 30 may perform demodulation, analog-to-digital (A/D) conversion, decoding, de-multiplexing, etc. in order to extract an image from the image signal. Also, the image processor 30 may perform scaling so that an image can be displayed with a predetermined size on the display 40 ; adjustment of characteristics such as brightness, color, contrast, etc. of an image; and various image enhancement processes for enhancing quality of an image.
[0041] The image processor 30 applies various imaging processes previously set up with regard to a source image which includes a broadcasting signal and an image signal received from an image source (not shown), such as an image signal received from the communicator 20 , an image signal photographed by the camera 10 , and an image signal stored in the storage 60 . The image processor 30 outputs the image signal subjected to such processes to the display 40 so that a processed source image can be displayed on the display 40 .
[0042] The display 40 may display an image based on an image signal output from the image processor 30 . There is no limit to the type of the display 40 . For example, the display may be one of various types of displays such as liquid crystal, plasma, a light-emitting diode, an organic light-emitting diode, a carbon nano-tube, nano-crystal, etc.
[0043] The display 40 may include an additional element in accordance with its type. For example, if the display 40 is achieved by the liquid crystal, the display 40 may include a liquid crystal display panel (not shown), a backlight unit (not shown) emitting light to the display panel, and a panel driving substrate (not shown) for driving the display panel.
[0044] Further, the display 40 displays an image of an external environment photographed by the camera 10 , so that a user can check it.
[0045] The storage 60 is provided as a nonvolatile memory (i.e., writable read only memory (ROM)) such as a flash memory, a hard disk drive, etc., and stores information and a program needed for operating the display apparatus 1 . The information needed for operating the display apparatus 1 may include all the information to be referred to while performing various functions, for example, information display, brightness control for an image, volume control, etc. The display apparatus 1 performs operations by executing a program stored in the storage 60 . Here, the program includes an operating system (OS), an application program, etc.
[0046] The storage 60 stores data about a face size, a distance between eyes, etc. of an average human. This data will be used in calculating an actual distance between the display apparatus 1 and a user by measuring a human's face size or the like within an image photographed by the camera 10 .
[0047] The controller 50 generally controls the display apparatus 1 . The controller 50 may include a control program, a nonvolatile memory such as a flash memory or the like for storing the control program, a volatile memory such as a random access memory for loading at least a part of the control program, a microprocessor for executing the loaded control program.
[0048] The controller 50 receives a photographed image involving a user and an external light source located in front of the display 40 from the camera 10 ; determines a reflection region from which light of the external light source is reflected with respect to a viewing position of the user within the region of the screen on the display 40 , based on the photographed image; and controls the brightness of the image in the reflection region of the screen to be greater than the brightness of the image in the other region.
[0049] FIG. 2 illustrates a use state schematically showing the display apparatus 1 according to an exemplary embodiment.
[0050] Referring to FIG. 2 , a user 70 is located at a right side and an external light source 80 is located at a left side in front of the display apparatus 1 . Here, the external light source 80 may be any light source that can emit light, such as a lighting device, the sun, etc. If the display 40 is viewed at the location of the user 70 , the light emitted from the external light source 80 is regularly reflected from the screen of the display 40 and appears in the screen of the display 40 . At this time, the user 70 views an external light source 41 reflected in a reflection region 42 of the screen on the display 40 . Like this, if an image is displayed in the screen on the display 40 , the image in the reflection region where external light is regularly reflected from the screen is more blurred than the image in the other region, thereby deteriorating visibility.
[0051] To solve the foregoing problems, the camera 10 placed in an upper portion of the display apparatus 1 according to an exemplary embodiment photographs the user 70 and the external light source 80 located in front of the display apparatus 1 and transmits the photographed image to the controller 50 . Then, the controller 50 measures a distance between the display 40 and the user 70 based on the photographed image, determines a position of the reflection region 42 where the external light source 80 is reflected in the screen on the display 40 based on the measured distance, and controls the brightness of the reflection region 42 to be greater than the brightness of the other region, thereby preventing the visibility from being deteriorated.
[0052] Below, a method of determining the reflection region 42 from which the external light source 80 is reflected in the screen on the display 40 will be described in more detail.
[0053] FIGS. 3 to 6 schematically show methods of calculating a position of a reflection region S in the display 40 apparatus according to exemplary embodiments.
[0054] First, the user 70 and the external light source 80 located in front of the display apparatus 1 are photographed by the camera 10 provided in the display apparatus 1 . Further, the camera 10 transmits the photographed image 12 to the controller 50 .
[0055] The controller 50 measures a face size, a distance between eyes, etc. of a user within the photographed image 12 and compares them with data about a face size, a distance between eyes, etc. of an average human stored in the storage 60 , thereby calculating a distance d 1 between the display 40 and the user 70 .
[0056] Further, the controller 50 calculates a horizontal distance f and a vertical distance d2 from the user 70 to the external light source 80 , based on the calculated distance d 1 between the display 40 and the user 70 . Here, an incident angle θ i of incident light emitted from the external light source 80 to the display 40 is equal to a reflective angle θ, of reflecting light reflected from the display 40 to the user 70 . Thus, if the incident angle θ i is obtained, it is possible to calculate a horizontal distance b between the user 70 and the reflection region S, thereby determining the position of the reflection region S on the display 40 .
[0057] In more detail, referring to FIG. 3 , d 1 , d 2 and f are constant values because they can be obtained by the controller through the photographed image 12 ; a is obtained from d 2 ·tan θ 1 ; and b is obtained from d 1 ·tan θ o . Here, a+2b is f and θ i is equal to θ o , and therefore θ i is tan −1 (f/(2d 1 +d 2 )). Thus, it is possible to obtain θ i by substituting d 1 , d 2 and f obtained as above.
[0058] FIGS. 4 to 6 are views for determining the reflection region S by calculating a horizontal position and a vertical position of the reflection region S on the display 40 through the foregoing calculating method.
[0059] FIG. 4 shows an example that horizontal positions w L1 and w L2 of the reflection regions due to two external light sources L1 and L2 in the display apparatus 1 are obtained based on the photographed image 12 of the user 70 and the external light sources L1 and L2 located in front of the display apparatus 1 .
[0060] To obtain the horizontal positions w L1 and w L2 of the reflection region, a horizontal direction of the photographed image 12 is arranged to be in parallel with a width direction w of the display apparatus 1 , and a horizontal directional center of the photographed image 12 is aligned with a width directional center of the display apparatus 1 . Further, if the position of the reflection region is calculated through the method shown in FIG. 3 , at the location of the user 70 , the horizontal position of the reflection region where the first external light source L1 is reflected in the display apparatus 1 is w L1 , and the horizontal position of the reflection region where the second external light source L2 is reflected in the display apparatus 1 is w L2 .
[0061] FIG. 5 shows an example that vertical positions h L1 and h L2 of the reflection regions due to two external light sources L1 and L2 in the display apparatus 1 are obtained based on the photographed image 12 of the user 70 and the external light sources L1 and L2 located in front of the display apparatus 1 .
[0062] To obtain the vertical positions h L1 and h L2 of the reflection region, a vertical direction of the photographed image 12 is arranged to be in parallel with a height direction h of the display apparatus 1 , and a vertical directional center of the photographed image 12 is aligned with a height directional center of the display apparatus 1 . Further, if the position of the reflection region is calculated through the method shown in FIG. 3 , at the location of the user 70 , the vertical position of the reflection region where the first external light source L1 is reflected in the display apparatus is h L1 , and the vertical position of the reflection region where the second external light source L2 is reflected in the display apparatus 1 is h L2 .
[0063] FIG. 6 shows the reflection region on the display 40 , based on the horizontal position of the reflection region obtained as shown in FIG. 4 and the vertical position of the reflection region obtained as shown in FIG. 5 . When the display 40 is viewed at the location of the user 40 , the reflection region where the first external light source L1 is reflected in the display 40 is S L1 where the line w L1 corresponding to the horizontal position intersects the line h L1 corresponding to the vertical position, and the reflection region where the second external light source L2 is reflected in the display 40 is S L2 where the line w L2 corresponding to the horizontal position intersects the line h L2 corresponding to the vertical position.
[0064] FIGS. 7 and 8 are schematic flowcharts of controlling the display apparatus according to exemplary embodiments.
[0065] Referring to FIG. 7 , a method of controlling the display apparatus 1 according to an exemplary embodiment includes photographing a front of the display 40 through the camera 10 (S 100 ), determining whether a user and external lighting are present in the photographed image (S 110 ), and selecting whether to control the brightness of the entire image to be greater than the brightness of a setup image (S 120 ) if the user and the external lighting are present in the photographed image (YES of S 110 ). If the user selects the brightness of the entire image to be greater than the brightness of the setup image (YES of S 120 ), the controller 50 controls the brightness of the screen on the display 40 to become brighter than the currently setup brightness. On the other hand, if the user selects the brightness of the entire image not to be greater than the brightness of the setup image (No of S 120 ), the controller 50 measures a distance between the display 40 and the user (S 130 ). After the distance between the display 40 and the user is measured (S 130 ), the controller 50 determines the reflection region, from which light emitted from the external light source is regularly reflected in the screen of the display 40 , through the calculation method shown in FIG. 3 (S 140 ). Further, the controller 50 adjusts the brightness of the image in the reflection region where the external light source is reflected in the screen of the display 40 to be greater than the brightness of the image in the other region (S 150 ), thereby improving visibility. Also, the controller 50 determines whether the photographed image taken by the camera 10 photographing a front of the display 40 involves the user and the external light (S 100 ), and does not control the brightness of the screen on the display 40 if the photographed image does not involve the user and the external light (No of S 110 ).
[0066] Referring to FIG. 8 , in a method of controlling the display apparatus 1 according to another exemplary embodiment, the camera 10 photographs a front of the display 40 (S 200 ), and the controller 50 measures a distance between a user and the display 40 if the photographed image involves the user and external light (S 210 ). When the distance between the display and the user is measured (S 210 ), the controller 50 determines the reflection region where light emitted from the external light source is regularly reflected from the screen of the display 40 , based on the measured distance through the calculating method shown in FIG. 3 (S 220 ). Further, the camera measures the intensity of the light emitted from the external light source (S 230 ), and the controller 50 controls the brightness of the image in the reflection region where the external light source is reflected in the screen of the display 40 to be greater than the brightness of the image in the other region (S 250 ) if the measured intensity of the light is less than or equal to a predetermined value (NO of S 240 ). On the other hand, if the measured intensity of the light is greater than or equal to a predetermined value (YES of S 240 ), the controller 50 maximizes the brightness of the image in the reflection region where the external light source is reflected in the screen of the display 40 (S 260 ), and adjusts one of a contrast value and an edge enhancement value of the image in the reflection region (S 270 ). The amount of the brightness adjustment of the image in the reflection region may be adjusted or may vary according to the measured intensity of the light emitted from the external light source. This is to improve visibility by increasing the contract value or the edge enhancement value or by increasing both the contract value and the edge enhancement value when the intensity of the light from the external light source is so strong that the visibility is deteriorated even though the brightness of the image in the reflection region is maximized.
[0067] In the display apparatus and the control method according to an exemplary embodiment, the brightness of an image in a region where an external light source is reflected in a screen of the display is controlled to be greater than the brightness of an image in the other region, thereby having an effect on improving a user's visibility.
[0068] Further, it is possible to increase the brightness of an image only in a certain region where an external light source is reflected in a screen of the display, thereby having an effect on reducing power consumption in the display apparatus as compared with that of when the brightness of the image of the entire screen region is increased.
[0069] Although a few exemplary embodiments have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these exemplary embodiments without departing from the principles and spirit of the inventive concept, the scope of which is defined in the appended claims and their equivalents. | Apparatuses and methods related to a display apparatus and a control method thereof, are provided. More particularly, the apparatuses and methods relate to a display apparatus and a control method thereof, in which brightness of an area of a screen is adjusted in consideration of an external light source reflected on the screen. | 8 |
[0001] This application is a divisional application of U.S. Ser. No. 10/289,558 filed Nov. 6, 2002. The entirety of U.S. Ser. No. 10/289,558 is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] In the manufacture of paper products, such as facial tissue, bath tissue, paper towels, dinner napkins and the like, a wide variety of product properties are imparted to the final product through the use of chemical additives applied in the wet end of the tissue making process. Two of the most important attributes imparted to tissue through the use of wet end chemical additives are strength and softness. Specifically for softness, a chemical debonding agent is normally used. Such debonding agents are typically quaternary ammonium compounds containing long chain alkyl groups. The cationic quaternary ammonium entity allows for the material to be retained on the cellulose via ionic bonding to anionic groups on the cellulose fibers. The long chain alkyl groups, provide softness to the tissue sheet by disrupting fiber-to-fiber hydrogen bonds in the sheet.
[0003] Such disruption of fiber-to-fiber bonds provides a two-fold purpose in increasing the softness of the tissue sheet. First, the reduction in hydrogen bonding produces a reduction in tensile strength thereby reducing the stiffness of the tissue sheet. Secondly, the debonded fibers provide a surface nap to the tissue sheet enhancing the “fuzziness” of the tissue sheet. This tissue sheet fuzziness may also be created through use of creping as well, where sufficient interfiber bonds are broken at the outer tissue surface to provide a plethora of free fiber ends on the tissue surface.
[0004] Both debonding and creping increase levels of lint and slough in the product. Indeed, while softness increases, it is at the expense of an increase in lint and slough in the tissue sheet relative to an untreated control. It can also be shown that in a blended (non-layered) tissue sheet that the level of lint and slough is inversely proportional to the tensile strength of the tissue sheet. Lint and slough can generally be defined as the tendency of the fibers in the paper sheet to be rubbed from the sheet when handled.
[0005] A multi-layered tissue structure to enhance the softness of the tissue sheet. One such embodiment, a thin layer of strong softwood fibers is used in the center layer to provide the necessary tensile strength for the product. The outer layers of such structures are composed of the shorter hardwood fibers, which may or may not contain a chemical debonder. A disadvantage to using layered structures is that while softness is increased the mechanism for such increase is believed due to an increase in the surface nap of the debonded, shorter fibers. As a consequence, such structures, while showing enhanced softness, do so with a trade-off of an increase in the level of lint and slough.
[0006] A chemical strength agent may be added in the wet-end to counteract the negative effects of the debonding agents. In a blended tissue sheet, the addition of such chemical strength agents reduces lint and slough levels. However, such reduction is done at the expense of surface feel and overall softness of the tissue sheet and becomes primarily a function of tissue sheet tensile strength. In a layered tissue sheet, strength chemicals are added preferentially to the center layer. While this perhaps helps to give a tissue sheet with an improved surface feel at a given tensile strength, such structures actually exhibit higher slough and lint at a given tensile strength, with the level of debonder in the outer layer being directly proportional to the increase in lint and slough. Co-pending U.S. patent application Ser. No. 09/736,924 (Shannon et al.) published on Aug. 22, 2002 discloses low slough tissue products made with acrylamides containing hydrophobic moieties. These synthetic polymers, while reducing the amount of slough compared to traditional debonders, still show an increase in slough with decreasing tensile strength.
[0007] Therefore there is a need for a means of reducing lint and slough in soft tissue sheets while maintaining the softness and strength of the tissue sheets. It is an objective of the present invention to design paper-making chemicals, more specifically tissue making chemicals, capable of reducing hydrogen bonding while also possessing ability to reduce lint and slough. It is a further objective to develop a process for making soft, low slough, low lint tissue products via wet end application of chemistry. It is a further objective of the present invention to make soft, absorbent, low lint and slough tissue products such as sanitary bath tissue, facial tissue, paper towels and the like via wet end application of such chemistry.
SUMMARY
[0008] It has now been discovered that certain cationic water dispersible synthetic co-polymers when applied to the wet end of the tissue machine may act as debonding chemicals while at the same time reducing the amount of lint and slough. Hence, soft tissue sheets having low lint and slough levels are obtained. The chemicals of the present invention are synthetic co-polymers formed from two or more different monomers. The synthetic co-polymers of the present invention are the polymerization product of a cationic monomer and at least one hydrophobic monomer. Additionally, the synthetic co-polymers of the present invention may also be the polymerization product of a cationic monomer, at least one hydrophobic monomer and optionally at least one non-ionic hydrophilic monomer. While not wishing to be bound by theory, it is believed that the synthetic co-polymers attach to the fibers via electrostatic attraction for the anionic fibers. As the synthetic co-polymers have no hydrogen or covalent bonding entity, they debond the fibers via the traditional mechanism by which chemical debonding agents function.
[0009] The synthetic co-polymers of the present invention are, however, good film forming agents and have good inter-molecular adhesive properties. Hence, the fibers are held in place by the co-polymer to co-polymer cohesive properties and good slough reduction occurs. The aliphatic hydrocarbon portion of the synthetic co-polymer molecule enables a significant level of debonding to occur and insures that the tissue sheet product has good surface nap or “fuzzy” feel. Yet, these fibers retain a significant inter-fiber bonding potential due to intra- and inter-molecular associative forces present in the synthetic co-polymers that help the fibers remain anchored to the tissue sheet. As such, fibers treated with these synthetic co-polymers produce a tissue sheet having lower lint and slough at a given tensile strength than a tissue sheet prepared with conventional softening agents or a combination of conventional softening agents and conventional strength agents.
[0010] The term “water dispersible” as used herein, means that the cationic synthetic co-polymers are either water soluble or capable of existing as stable colloidal, self-emulsifiable or other type dispersions in water without the presence of added emulsifiers. Added emulsifiers may be employed within the scope of the present invention to aid in the polymerization of the cationic synthetic co-polymers or assist in compatibilizing the cationic synthetic co-polymers with other chemical agents used in the tissue sheet, however, the emulsifiers are not essential to formation of stable dispersions or solutions of the cationic synthetic co-polymers in water.
[0011] It is known in the art to add latex polymer emulsions of styrene butadiene rubber binders and ethylene vinyl acetate binders topically to a formed tissue sheet to decrease strength loss associated with topical application of debonders and other softening agents. Large amounts of emulsifiers are used in the production of such latex polymers and these emulsifiers are critical to the stability of the latex polymers in water. The latex polymers are not of themselves water dispersible. The emulsions are susceptible to breaking, causing a film of the latex polymer to develop on processing equipment. This film continues to deposit on equipment to the point where shutdown and clean-up of the equipment is required. As the latex polymers are not water dispersible clean-up can be time consuming, costly and environmentally unfriendly. Furthermore, the lack of water dispersability makes tissue sheets made with these latex polymers difficult to impossible to redisperse, causing a significant economic penalty to be incurred in tissue sheets employing these traditional latex polymers. As these latex polymers are not cationic, wet end application of these latex polymers is significantly constrained and the latex polymers demonstrate ability to only increase strength. The disadvantages to using these materials have severely limited commercial use of traditional latex polymers in tissue-based products.
[0012] It is known wherein a procedure for creping paper comprises incorporation in paper pulp or a paper sheet of a cationic water soluble addition polymer containing amine groups and optionally quaternary ammonium groups. Optionally the addition polymer may contain units of one other monoethylenically unsaturated monomers in a level such that the addition polymer remains water soluble. A critical aspect of such a procedure is the presence of free amine groups which, when used in conjunction with the optional quaternary group, must be present in a ratio>1:1 relative to the quaternary group. The addition polymers are used as creping facilitators to promote enhanced Yankee dryer adhesion. However, enhanced Yankee dryer adhesion is typically not a desirable characteristic when making low slough and lint tissue-based products, such adhesion being known to those skilled in the art to increase levels of lint and slough. Furthermore, the presence of the free amine groups makes the addition polymers sensitive to pH when applied in the wet end of tissue making processes, turning the tissue sheet hydrophobic under acidic conditions and imparting undesired wet strength when used under basic conditions. An additional consideration when using the addition polymers is the presence of the free amine groups, capable of reacting with other papermaking additives, such as those containing aldehyde and azetidinium groups, thereby risking the reduction of the efficacy of those additives.
[0013] Hence, in one aspect, the present invention resides in a tissue chemical additive capable of simultaneously debonding and reducing lint and slough, the tissue chemical additive comprising a cationic synthetic water dispersible co-polymer containing a hydrophobic portion such that the hydrophobic portion is capable of demonstrating intra-molecular adhesive properties in the dry state while exhibiting ability to debond a tissue sheet when applied to the tissue sheet at a low consistency. The synthetic co-polymers have the following general structure:
[0000]
Wherein:
[0014] R 1 , R 2 , R 3 are independently H, C 1-4 alkyl radical, or mixtures thereof.
R 4 is a C 1 -C 8 alkyl radical or mixtures thereof.
Z 1 is a bridging radical attaching the R 4 functionality to the polymer backbone. Examples include, but are not limited to, —O—, —COO—, —OOC—, —CONH—, —NHCO—, and mixtures thereof.
Q 1 is a functional group containing a cationic quaternary ammonium radical.
Q 2 is an optional group comprised of a non-ionic hydrophilic or water soluble monomer or monomers (and mixtures thereof) incorporated into the synthetic co-polymer so as to make the synthetic co-polymer more hydrophilic. Q 2 possesses limited ability to hydrogen or covalently bond to cellulose fibers, such bonding resulting in an increase in stiffness of the tissue sheet. Suitable hydrophilic monomers or water-soluble nonionic monomers for use in the cationic synthetic co-polymers of the present invention include, but are not limited to, monomers, such as, hydroxyalkyl acrylates and hydroxyalkyl methacrylates, such as hydroxyethyl methacrylate (HEMA); hydroxyethyl acrylate; polyalkoxyl acrylates, such as polyethyleneglycol acrylates; and, polyalkoxyl methacrylates, such as polyethyleneglycol methacrylates (“PEG-MA”). Other suitable hydrophilic monomers or water-soluble nonionic monomers for use in the ion-sensitive cationic synthetic co-polymers of the present invention include, but are not limited to, diacetone acrylamide, N-vinylpyrrolidinone, and N-vinylformamide.
[0015] The mole ratio of z:x will specifically range from about 0:1 to about 4:1, more specifically from about 0:1 to about 1:1, and most specifically from about 0:1 to about 1:3. The mole ratio of (x+z):y may be from about 0.98:0.02 to about 1:1, and most specifically from about 0.95:0.05 to about 0.70:0.30.
[0016] Hence, in another aspect, the present invention resides in a soft, low lint and slough absorbent paper sheet, such as a tissue sheet, comprising a cationic synthetic water dispersible co-polymer containing a hydrophobic portion such that the hydrophobic portion is capable of demonstrating intermolecular associative properties in the dry state while exhibiting ability to debond a tissue sheet when applied to the tissue sheet at a low consistency. The cationic water dispersible synthetic co-polymers have the following general structure:
[0000]
Wherein:
[0017] R 1 , R 2 , R 3 are independently H, C 1-4 alkyl radical, or mixtures thereof.
R 4 is a C 1 -C 8 alkyl radical or mixtures thereof.
Z 1 is a bridging radical attaching the R 4 functionality to the polymer backbone. Examples include, but are not limited to, —O—, —COO—, —OOC—, —CONH—, —NHCO—, and mixtures thereof.
Q 1 is a functional group containing a cationic quaternary ammonium radical.
Q 2 is an optional group comprised of a non-ionic hydrophilic or water soluble monomer or monomers (and mixtures thereof) incorporated into the synthetic co-polymer so as to make the synthetic co-polymer more hydrophilic. Q 2 possesses limited ability to hydrogen or covalently bond to cellulose fibers, such bonding resulting in an increase in stiffness of the tissue sheet. Suitable hydrophilic monomers or water-soluble nonionic monomers for use in the cationic synthetic co-polymers of the present invention include, but are not limited to, monomers, such as, hydroxyalkyl acrylates and hydroxyalkyl methacrylates, such as hydroxyethyl methacrylate (HE MA); hydroxyethyl acrylate; polyalkoxyl acrylates, such as polyethyleneglycol acrylates; and, polyalkoxyl methacrylates, such as polyethyleneglycol methacrylates (“PEG-MA”). Other suitable hydrophilic monomers or water-soluble nonionic monomers for use in the ion-sensitive cationic synthetic co-polymers of the present invention include, but are not limited to, diacetone acrylamide, N-vinylpyrrolidinone, and N-vinylformamide.
[0018] The mole ratio of z:x will specifically range from about 0:1 to about 4:1, more specifically from about 0:1 to about 1:1, and most specifically from about 0:1 to about 1:3. The mole ratio of (x+z):y may be from about 0.98:0.02 to about 1:1, and most specifically from about 0.95:0.05 to about 0.70:0.30.
[0019] In another aspect, the present invention resides in a method of making a soft, low lint tissue sheet, comprising the steps of: (a) forming an aqueous suspension comprising papermaking fibers; (b) depositing the aqueous suspension of papermaking fibers onto a forming fabric to form a wet tissue sheet; and, (c) dewatering and drying the wet tissue sheet to form a paper sheet, wherein a cationic water dispersible synthetic co-polymer containing a hydrophobic portion such that the hydrophobic portion is capable of demonstrating intra-molecular adhesive properties in the dry state while exhibiting an ability to debond the tissue sheet is added to the aqueous suspension of the papermaking fibers or topically to the wet tissue sheet at a consistency of about 80% or less, the cationic water dispersible synthetic co-polymer has the following general structure:
[0000]
Wherein:
[0020] R 1 , R 2 , R 3 are independently H, C 1-4 alkyl radical, or mixtures thereof.
R 4 is a C 1 -C 8 alkyl radical or mixtures thereof.
Z 1 is a bridging radical attaching the R 4 functionality to the polymer backbone. Examples include, but are not limited to, —O—, —COO—, —OOC—, —CONH—, —NHCO—, and mixtures thereof.
Q 1 is a functional group containing a cationic quaternary ammonium radical.
Q 2 is an optional group comprising a non-ionic hydrophilic or water soluble monomer or monomers (and mixtures thereof) incorporated into the synthetic co-polymer so as to make the synthetic co-polymer more hydrophilic. Q 2 possesses limited ability to hydrogen or covalently bond to cellulose fibers, such bonding resulting in an increase in stiffness of the tissue sheet. Suitable hydrophilic monomers or water-soluble nonionic monomers for use in the cationic synthetic co-polymers of the present invention include, but are not limited to, monomers, such as, hydroxyalkyl acrylates and hydroxyalkyl methacrylates, such as hydroxyethyl methacrylate (HEMA); hydroxyethyl acrylate; polyalkoxyl acrylates, such as polyethyleneglycol acrylates; and, polyalkoxyl methacrylates, such as polyethyleneglycol methacrylates (“PEG-MA”). Other suitable hydrophilic monomers or water-soluble nonionic monomers for use in the ion-sensitive cationic synthetic co-polymers of the present invention include, but are not limited to, diacetone acrylamide, N-vinylpyrrolidinone, and N-vinylformamide.
[0021] The mole ratio of z:x will specifically range from about 0:1 to about 4:1, more specifically from about 0:1 to about 1:1, and most specifically from about 0:1 to about 1:3. The mole ratio of (x+z):y may be from about 0.98:0.02 to about 1:1, and most specifically from about 0.95:0.05 to about 0.70:0.30.
[0022] The amount of the cationic synthetic co-polymer additive added to the papermaking fibers or the paper or tissue sheet may be from about 0.02 to about 5 weight percent, on a dry fiber basis, more specifically from about 0.05 to about 3 weight percent, and still more specifically from about 0.1 to about 2 weight percent. The synthetic co-polymer may be added to the fibers or paper or tissue sheet at any point in the process, but it can be particularly advantageous to add the synthetic co-polymer to the fibers while the fibers are suspended in water, before or after formation but prior to final drying of the sheet. This may include, for example, addition in the pulp mill or to the pulper, a machine chest, the headbox, or to the paper or tissue sheet prior to being dried where the consistency of the tissue sheet is about 80% or less.
[0023] In order to be an effective cationic synthetic co-polymer or cationic synthetic polymer additive suitable for use in tissue applications, the cationic synthetic co-polymer or cationic synthetic co-polymer additive should desirably be (1) water soluble or water dispersible; (2) safe (not toxic); and, (3) relatively economical. In addition to the foregoing factors, the cationic synthetic co-polymers and cationic synthetic co-polymer additives of the present invention, when used as a binder composition for a tissue sheet substrate, such as a facial, bath or towel product should be (4) processable on a commercial basis; i.e., may be applied relatively quickly on a large scale basis, such as by spraying (which thereby requires that the binder composition have a relatively low viscosity at high shear); and, (5) provide acceptable levels of sheet or substrate wettability. The cationic synthetic co-polymers and cationic synthetic co-polymer additives of the present invention and articles made therewith, especially facial tissue, bath tissue and towels comprising the particular compositions set forth below, can meet any or all of the above criteria. Of course, it is not necessary for all of the advantages of the preferred embodiments of the present invention to be met to fall within the scope of the present invention.
DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a graph comparing GMT and slough values for a topical application to a wet sheet of a particular synthetic co-polymer of the present invention and controls.
[0025] FIG. 2 is a graph comparing GMT and softness values for a topical application to a wet sheet of a particular synthetic co-polymer of the present invention and controls.
[0026] FIG. 3 is a graph comparing slough and softness values for a topical application to a wet sheet of a particular synthetic co-polymer of the present invention and controls.
[0027] FIG. 4 is a graph comparing GMT and slough values for a topical application to a wet sheet of various synthetic co-polymers of the present invention and controls.
[0028] FIG. 5 is a graph comparing slough and softness values for a topical application to a wet sheet of various synthetic co-polymers of the present invention and controls.
[0029] FIG. 6 is a graph comparing GMT and slough values for bulk wet end application of various synthetic co-polymers of the present invention and controls.
[0030] FIG. 7 is a graph comparing slough and softness values for bulk wet end application of various synthetic co-polymers of the present invention and controls.
[0031] FIG. 8 is a schematic diagram of testing equipment used to measure lint and slough.
DETAILED DESCRIPTION OF THE INVENTION
Cationic Synthetic Co-Polymer Formulations
[0032] Suitable hydrophobic monomers for incorporating a hydrophobic functionality into the cationic synthetic co-polymers of the present invention include, but are not limited to, alkyl acrylates, methacrylates, acrylamides, methacrylamides, tiglates and crotonates, including butyl acrylate, butyl methacrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, 1-Ethylhexyl tiglate, t-butyl acrylate, butyl crotonate, butyl tiglate, sec-Butyl tiglate, Hexyl tiglate, Isobutyl tiglate, hexyl crotonate, butyl crotonate, n-butyl acrylamide, t-butyl acrylamide, N-(Butoxymethyl)acrylamide, N-(Isobutoxymethyl)acrylamide, and the like including mixtures of the monomers all of which are known commercially available materials. Also known are various vinyl ethers including, but not limited to, n-butyl vinyl ether, 2-ethylhexyl vinyl ether, and the corresponding esters including vinyl pivalate, vinyl butyrate, 2-ethylhexanoate, and the like including mixtures of the monomers, all of which are suitable for incorporation of the hydrophobic aliphatic hydrocarbon moiety.
[0033] Suitable monomers for incorporating a cationic charge functionality into the synthetic co-polymer include, but are not limited to, [2-(methacryloyloxy)ethyl] trimethylammonium methosulfate (METAMS); dimethyldiallyl ammonium chloride (DMDAAC); 3-acryloamido-3-methyl butyl trimethyl ammonium chloride (AMBTAC); trimethylamino methacrylate; vinyl benzyl trimethyl ammonium chloride (VBTAC); 2-[(acryloyloxy)ethyl]trimethylammonium chloride; [2-(methacryloyloxy)ethyl] trimethylammonium chloride.
[0034] Examples of preferred cationic monomers for the cationic synthetic co-polymers of the present invention are [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride, [2-(methacryloyloxy)ethyl] trimethyl ammonium methosulfate, [2-(methacryloyloxy)ethyl] trimethyl ammonium ethosulfate.
[0035] Suitable hydrophilic monomers or water-soluble nonionic monomers for use in the cationic synthetic co-polymers of the present invention include, but are not limited to N- and N,N-substituted acrylamide and methacrylamide based monomers, such as N,N-dimethyl acrylamide, N-ethyl acrylamide, N-isopropyl acrylamide, and hydroxymethyl acrylamide; acrylate or methacrylate based monomers, such as, hydroxyalkyl acrylates; hydroxyalkyl methacrylates, such as hydroxyethyl methacrylate (HEMA); hydroxyethyl acrylate; polyalkoxyl acrylates, such as polyethyleneglycol acrylates; and, polyalkoxyl methacrylates, such as polyethyleneglycol methacrylates (“PEG-MA”). Other suitable hydrophilic monomers or water-soluble nonionic monomers for use in the ion-sensitive cationic synthetic co-polymers of the present invention include, but are not limited to, N-vinylpyrrolidinone and N-vinylformamide.
[0036] For the cationic synthetic co-polymers of the present invention the mole % of hydrophobic monomers will range from about 40 mole % to about 98 mole % of the total monomer composition, the amount of cationic monomers will range from about 2 mole % to about 50 mole % of the total monomer composition. The amount of optional hydrophilic monomers will range from about 0 mole % to about 58 mole % of the total monomer composition. Most preferably, the mole percent of hydrophobic monomers is from about 50 mole % to about 95 mole % of the total monomer composition, the mole % of cationic monomers is most preferably from about 5 mole % to about 30 mole % of the total monomer composition, and the amount of optional hydrophilic monomers is most preferably from about 0 mole % to about 20 mole % of the total monomer composition.
[0037] The synthetic co-polymers of the present invention may have an average molecular weight average molecular weight ranging from about 10,000 to about 5,000,000. More specifically, the cationic water dispersible synthetic co-polymers of the present invention have a weight average molecular weight ranging from about 25,000 to about 2,000,000, or, more specifically still, from about 50,000 to about 1,000,000.
[0038] Another advantage to the disclosed cationic synthetic co-polymers is ability to produce sheets having low stiffness due to relatively low glass transition temperatures. While the cationic synthetic co-polymers of the present invention may have a wide range of glass transition temperature the glass transition temperature may be about 100° C. or less, more specifically about 70° C. or less, and most specifically about 40° C. or less. Some of the cationic synthetic co-polymers of the present invention may show more than one glass transition temperature. In such cases, the glass transition temperature of the lowest glass transition temperature may be about 100° C. or less, more specifically about 70° C. or less, and most specifically about 40° C. or less.
[0039] The cationic synthetic co-polymers of the present invention may be prepared according to a variety of polymerization methods, desirably a solution polymerization method. Suitable solvents for the polymerization method include, but are not limited to, lower alcohols such as methanol, ethanol and propanol; a mixed solvent comprising water and one or more lower alcohols mentioned above; and, a mixed solvent comprising water and one or more lower ketones such as acetone or methyl ethyl ketone.
[0040] In the polymerization methods which may be utilized in the present invention, any free radical polymerization initiator may be used. Selection of a particular polymerization initiator may depend on a number of factors including, but not limited to, the polymerization temperature, the solvent, and the monomers used. Suitable polymerization initiators for use in the present invention include, but are not limited to, 2,2′-azobisisobutyronitrile, 2,2′-azobis(2-methylbutyronitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(2-amidinopropane)dihydrochloride, 2,2′-azobis(N,N′-dimethyleneisobutylamidine), potassium persulfate, ammonium persulfate, and aqueous hydrogen peroxide. The amount of polymerization initiator may desirably range from about 0.01 to about 5 weight percent based on the total weight of monomer present.
[0041] The polymerization temperature may vary depending on the polymerization solvent, monomers, and polymerization initiator used, but in general, ranges from about 20° C. to about 90° C. The polymerization time generally ranges from about 2 to about 8 hours.
[0042] The cationic synthetic co-polymer formulations of the present invention may also be delivered in emulsion form, whereby an aqueous polymerization process is used in conjunction with a surfactant or set of surfactants, such polymerization methods being known to those skilled in the art. The surfactants may be cationic or non-ionic, but more specifically non-ionic.
[0043] The amount of the cationic synthetic co-polymer additive added to the papermaking fibers or the paper or tissue sheet may be from about 0.01 to about 5 weight percent, on a dry fiber basis, more specifically from about 0.05 to about 3 weight percent, and still more specifically from about 0.1 to about 2 weight percent. The cationic synthetic co-polymer may be added to the papermaking fibers or the paper or tissue sheet at any point in the process. In one embodiment, the cationic synthetic co-polymers of the present invention may be added after the tissue sheet is formed, more specifically, to an existing wet tissue sheet. The solids level of the wet tissue sheet is preferably about 80% or lower (i.e., the tissue sheet comprises about 20 grams of dry solids and about 80 grams of water). More specifically, the solids level of the tissue sheet during the application of the cationic synthetic co-polymers may be most specifically about 60% or less, and most specifically about 50% or less. The application of the cationic synthetic co-polymer to the tissue sheet via this process may be accomplished by any method known in the art including but not limited to:
A spray applied to the fibrous tissue sheet. For example, spray nozzles may be mounted over a moving wet tissue sheet to apply a desired dose of a synthetic co-polymer chemical additive solution to the wet tissue sheet. Nebulizers can also be used to apply a light mist to a surface of a wet tissue sheet. Non-contact printing methods such as ink jet printing, digital printing of any kind, and the like. Coating onto one or both surfaces of the wet tissue sheet, such as blade coating, air knife coating, short dwell coating, cast coating, and the like. Extrusion from a die head such as UFD spray tips, such as available from ITW-Dynatec of Henderson, Tenn., of the cationic synthetic co-polymer or cationic synthetic co-polymer additive in the form of a solution, a dispersion or emulsion, or a viscous mixture. Impregnation of the wet tissue sheet with a solution or slurry, wherein the compound penetrates a significant distance into the thickness of the wet tissue sheet, such as about 20% or greater of the thickness of the wet tissue sheet, more specifically about 30% or greater, and most specifically about 70% or greater of the thickness of the wet tissue sheet, including completely penetrating the wet tissue sheet throughout the full extent of its thickness. One useful method for impregnation of a wet tissue sheet is the Hydra-Sizer® system, produced by Black Clawson Corp., Watertown, N.Y., as described in “New Technology to Apply Starch and Other Additives,” Pulp and Paper Canada, 100(2): T42-T44 (Feb. 1999). This system consists of a die, an adjustable support structure, a catch pan, and an additive supply system. A thin curtain of descending liquid or slurry is created which contacts the moving tissue sheet beneath it. Wide ranges of applied doses of the coating material, such as the cationic synthetic co-polymer, or cationic synthetic co-polymer additive, may be achieved with good runnability. The system may also be applied to curtain coat a relatively dry tissue sheet, such as a tissue sheet just before or after creping. Foam application of the cationic synthetic co-polymer or cationic synthetic co-polymer additive to the wet tissue sheet (e.g., foam finishing), either for topical application or for impregnation of the cationic synthetic co-polymer or cationic synthetic co-polymer additive into the wet tissue sheet under the influence of a pressure differential (e.g., vacuum-assisted impregnation of the foam). Principles of foam application of additives such as binder agents are described in U.S. Pat. No. 4,297,860, issued on Nov. 3, 1981 to Pacifici et al. and U.S. Pat. No. 4,773,110, issued on Sep. 27, 1988 to G. J. Hopkins, the disclosures of both which are herein incorporated by reference to the extent that they are non-contradictory herewith. Application of the cationic synthetic co-polymer or cationic synthetic co-polymer additive by spray or other means to a moving belt or fabric which in turn contacts the tissue sheet to apply the cationic synthetic co-polymer or cationic synthetic co-polymer additive to the tissue sheet, such as is disclosed in WO 01/49937 under the name of S. Eichhorn, published on Jun. 12, 2001.
[0051] The cationic synthetic co-polymer or cationic synthetic co-polymer additive may also be added prior to formation of the tissue sheet such as when the fibers are suspended in water. This may include, for example, addition in the pulp mill or to the pulper, a machine chest, the headbox or to the tissue sheet prior to being dried where the consistency is about 80% or less.
The most preferred means for addition prior to the tissue sheet formation is direct addition to a fibrous slurry, such as by injection of the cationic synthetic co-polymer or cationic synthetic co-polymer additive into a fibrous slurry prior to entry in the headbox. Slurry consistency can be from about 0.2% to about 50%, specifically from about 0.2% to about 10%, more specifically from about 0.3% to about 5%, and most specifically from about 1% to about 4%. Application of the cationic synthetic co-polymer or cationic synthetic co-polymer additive to individualized fibers. For example, comminuted or flash dried fibers may be entrained in an air stream combined with an aerosol or spray of the cationic synthetic co-polymer or cationic synthetic co-polymer additive to treat individual fibers prior to incorporation of the treated fibers into a tissue sheet or other fibrous product.
[0054] The tissue sheet comprising the cationic synthetic co-polymers of the present invention may be blended or layered sheets, wherein either a heterogeneous or homogeneous distribution of fibers is present in the z-direction of the sheet. In some embodiments, the cationic synthetic co-polymers may be added to all the fibers in the tissue sheet. In other embodiments, the cationic synthetic co-polymers may be added to only selective fibers in the tissue sheet, such methods being well known to those skilled in the art. In a specific embodiment of the present invention, the tissue sheet is a layered tissue sheet comprising two or more layers comprising distinct hardwood and softwood layers, wherein the cationic synthetic co-polymers of the present invention are added to only the hardwood fibers. In another embodiment, the cationic synthetic co-polymers of the present invention may be added to all the fibers.
[0055] The tissue sheet to be treated may be made by any method known in the art. The tissue sheet may be wetlaid, such as tissue sheet formed with known papermaking techniques wherein a dilute aqueous fiber slurry is disposed on a moving wire to filter out the fibers and form an embryonic tissue sheet which is subsequently dewatered by combinations of units including suction boxes, wet presses, dryer units, and the like. Examples of known dewatering and other operations are disclosed in U.S. Pat. No. 5,656,132, issued on Aug. 12, 1997 to Farrington, Jr. et al. Capillary dewatering may also be applied to remove water from the tissue sheet, as disclosed in U.S. Pat. Nos. 5,598,643, issued on Feb. 4, 1997 and 4,556,450, issued on Dec. 3, 1985, both to S. C. Chuang et al., the disclosures of both which are herein incorporated by reference to the extent that they are non-contradictory herewith.
[0056] Drying operations can include drum drying, through drying, steam drying such as superheated steam drying, displacement dewatering, Yankee drying, infrared drying, microwave drying, radiofrequency drying in general, and impulse drying, as disclosed in U.S. Pat. No. 5,353,521, issued on Oct. 11, 1994 to Orloff and U.S. Pat. No. 5,598,642, issued on Feb. 4, 1997 to Orloff et al., the disclosures of both which are herein incorporated by reference to the extent that they are non-contradictory herewith. Other drying technologies may be used, such as methods employing differential gas pressure include the use of air presses as disclosed U.S. Pat. No. 6,096,169, issued on Aug. 1, 2000 to Hermans et al. and U.S. Pat. No. 6,143,135, issued Nov. 7, 2000 to Hada et al., the disclosure of both which are herein incorporated by reference to the extent they are non-contradictory herewith. Also relevant are the paper machines disclosed in U.S. Pat. No. 5,230,776, issued on Jul. 27, 1993 to I. A. Andersson et al.
[0057] For tissue sheets, both creped and uncreped methods of manufacture may be used. Uncreped tissue production is disclosed in U.S. Pat. No. 5,772,845 issued on Jun. 30, 1998 to Farrington, Jr. et al., the disclosure of which is herein incorporated by reference to the extent that they are non-contradictory herewith. Creped tissue production is disclosed in U.S. Pat. No. 5,637,194, issued on Jun. 10, 1997 to Ampulski et al.; U.S. Pat. No. 4,529,480, issued on Jul. 16, 1985 to Trokhan; U.S. Pat. No. 6,103,063, issued on Aug. 15, 2000 to Oriaran et al.; and, U.S. Pat. No. 4,440,597, issued on Apr. 3, 1984 to Wells et al., the disclosures of all which are herein incorporated by reference to the extent that they are non-contradictory herewith. Also suitable for application of the synthetic co-polymers and synthetic co-polymer chemical additives of the present invention are tissue sheets that are pattern densified or imprinted, such as the tissue sheets disclosed in any of the following U.S. Pat. Nos. 4,514,345, issued on Apr. 30, 1985 to Johnson et al.; 4,528,239, issued on Jul. 9, 1985 to Trokhan; 5,098,522, issued on Mar. 24, 1992; 5,260,171, issued on Nov. 9, 1993 to Smurkoski et al.; 5,275,700, issued on Jan. 4, 1994 to Trokhan; 5,328,565, issued on Jul. 12, 1994 to Rasch et al.; 5,334,289, issued on Aug. 2, 1994 to Trokhan et al.; 5,431,786, issued on Jul. 11, 1995 to Rasch et al.; 5,496,624, issued on Mar. 5, 1996 to Steltjes, Jr. et al.; 5,500,277, issued on Mar. 19, 1996 to Trokhan et al.; 5,514,523, issued on May 7, 1996 to Trokhan et al.; 5,554,467, issued on Sep. 10, 1996, to Trokhan et al.; 5,566,724, issued on Oct. 22, 1996 to Trokhan et al.; 5,624,790, issued on Apr. 29, 1997 to Trokhan et al.; and, 5,628,876, issued on May 13, 1997 to Ayers et al., the disclosures of which are incorporated herein by reference to the extent that they are non-contradictory herewith. Such imprinted tissue sheets may have a network of densified regions that have been imprinted against a drum dryer by an imprinting fabric, and regions that are relatively less densified (e.g., “domes” in the tissue sheet) corresponding to deflection conduits in the imprinting fabric, wherein the tissue sheet superposed over the deflection conduits was deflected by an air pressure differential across the deflection conduit to form a lower-density pillow-like region or dome in the tissue sheet.
[0058] The term “tissue” as used herein is differentiated from other paper or tissue products in terms of its bulk. The bulk of the tissue products of the present invention is calculated as the quotient of the Caliper (hereinafter defined), expressed in microns, divided by the basis weight, expressed in grams per square meter. The resulting bulk is expressed as cubic centimeters per gram. Writing papers, newsprint and other such papers have higher strength and density (low bulk) in comparison to tissue products which tend to have much higher calipers for a given basis weight. For writing and printing papers, both bulk and surface strength are extremely important as well as high stiffness. The use of bulk or surface debonders to create bulk in papers other than tissue products goes against maximizing bulk and surface strength in printing papers. The tissue products of the present invention have a bulk about 2 cm 3 /g or greater, more specifically about 2.5 cm 3 /g or greater, and still more specifically about 3 cm 3 /g or greater.
Optional Chemical Additives
[0059] Optional chemical additives may also be added to the aqueous papermaking furnish or to the embryonic tissue sheet to impart additional benefits to the tissue product and process and are not antagonistic to the intended benefits of the present invention. The following materials are included as examples of additional chemicals that may be applied to the tissue sheet with the cationic synthetic co-polymers and cationic synthetic co-polymer additives of the present invention. The chemicals are included as examples and are not intended to limit the scope of the present invention. Such chemicals may be added at any point in the papermaking process, such as before or after addition of the cationic synthetic co-polymers and/or cationic synthetic co-polymer additives of the present invention. They may also be added simultaneously with the cationic copolymers and/or cationic synthetic co-polymer additives, either blended with the cationic synthetic co-polymers and/or cationic synthetic co-polymer additives of the present invention or as separate additives.
Charge Control Agents
[0060] Charge promoters and control agents are commonly used in the papermaking process to control the zeta potential of the papermaking furnish in the wet end of the process. These species may be anionic or cationic, most usually cationic, and may be either naturally occurring materials such as alum or low molecular weight high charge density synthetic polymers typically of molecular weight of about 500,000 or less. Drainage and retention aids may also be added to the furnish to improve formation, drainage and fines retention. Included within the retention and drainage aids are microparticle systems containing high surface area, high anionic charge density materials.
Strength Agents
[0061] Wet and dry strength agents may also be applied to the tissue sheet. As used herein, “wet strength agents” refer to materials used to immobilize the bonds between fibers in the wet state. Typically, the means by which fibers are held together in paper and tissue products involve hydrogen bonds and sometimes combinations of hydrogen bonds and covalent and/or ionic bonds. In the present invention, it may be useful to provide a material that will allow bonding of fibers in such a way as to immobilize the fiber-to-fiber bond points and make them resistant to disruption in the wet state. In this instance, the wet state usually will mean when the product is largely saturated with water or other aqueous solutions, but could also mean significant saturation with body fluids such as urine, blood, mucus, menses, runny bowel movement, lymph, and other body exudates.
[0062] Any material that when added to a tissue sheet or sheet results in providing the tissue sheet with a mean wet geometric tensile strength:dry geometric tensile strength ratio in excess of about 0.1 will, for purposes of the present invention, be termed a wet strength agent. Typically these materials are termed either as permanent wet strength agents or as “temporary” wet strength agents. For the purposes of differentiating permanent wet strength agents from temporary wet strength agents, the permanent wet strength agents will be defined as those resins which, when incorporated into paper or tissue products, will provide a paper or tissue product that retains more than 50% of its original wet strength after exposure to water for a period of at least five minutes. Temporary wet strength agents are those which show about 50% or less than, of their original wet strength after being saturated with water for five minutes. Both classes of wet strength agents find application in the present invention. The amount of wet strength agent added to the pulp fibers may be about 0.1 dry weight percent or greater, more specifically about 0.2 dry weight percent or greater, and still more specifically from about 0.1 to about 3 dry weight percent, based on the dry weight of the fibers.
[0063] Permanent wet strength agents will typically provide a more or less long-term wet resilience to the structure of a tissue sheet. In contrast, the temporary wet strength agents will typically provide tissue sheet structures that had low density and high resilience, but would not provide a structure that had long-term resistance to exposure to water or body fluids.
Wet and Temporary Wet Strength Agents
[0064] The temporary wet strength agents may be cationic, nonionic or anionic. Such compounds include PAREZ™ 631 NC and PAREZ® 725 temporary wet strength resins that are cationic glyoxylated polyacrylamide available from Cytec Industries (West Paterson, N.J.). This and similar resins are described in U.S. Pat. No. 3,556,932, issued on Jan. 19, 1971 to Coscia et al. and U.S. Pat. No. 3,556,933, issued on Jan. 19, 1971 to Williams et al. Hercobond 1366, manufactured by Hercules, Inc., located at Wilmington, Del., is another commercially available cationic glyoxylated polyacrylamide that may be used in accordance with the present invention. Additional examples of temporary wet strength agents include dialdehyde starches such as Cobond® 1000 from National Starch and Chemical Company and other aldehyde containing polymers such as those described in U.S. Pat. No. 6,224,714 issued on May 1, 2001 to Schroeder et al.; U.S. Pat. No. 6,274,667 issued on Aug. 14, 2001 to Shannon et al.; U.S. Pat. No. 6,287,418 issued on Sep. 11, 2001 to Schroeder et al.; and, U.S. Pat. No. 6,365,667 issued on Apr. 2, 2002 to Shannon et al., the disclosures of which are herein incorporated by reference to the extend they are non-contradictory herewith.
[0065] Permanent wet strength agents comprising cationic oligomeric or polymeric resins may be used in the present invention. Polyamide-polyamine-epichlorohydrin type resins such as KYMENE 557H sold by Hercules, Inc., located at Wilmington, Del., are the most widely used permanent wet-strength agents and are suitable for use in the present invention. Such materials have been described in the following U.S. Pat. Nos. 3,700,623 issued on Oct. 24, 1972 to Keim; 3,772,076 issued on Nov. 13, 1973 to Keim; 3,855,158 issued on Dec. 17, 1974 to Petrovich et al.; 3,899,388 issued on Aug. 12, 1975 to Petrovich et al.; 4,129,528 issued on Dec. 12, 1978 to Petrovich et al.; 4,147,586 issued on Apr. 3, 1979 to Petrovich et al.; and, 4,222,921 issued on Sep. 16, 1980 to van Eenam. Other cationic resins include polyethylenimine resins and aminoplast resins obtained by reaction of formaldehyde with melamine or urea. It is often advantageous to use both permanent and temporary wet strength resins in the manufacture of tissue products with such use being recognized as falling within the scope of the present invention.
Dry Strength Agents
[0066] Dry strength agents may also be applied to the tissue sheet without affecting the performance of the disclosed cationic synthetic co-polymers of the present invention. Such materials used as dry strength agents are well known in the art and include but are not limited to modified starches and other polysaccharides such as cationic, amphoteric, and anionic starches and guar and locust bean gums, modified polyacrylamides, carboxymethylcellulose, sugars, polyvinyl alcohol, chitosans, and the like. Such dry strength agents are typically added to a fiber slurry prior to tissue sheet formation or as part of the creping package. It may at times, however, be beneficial to blend the dry strength agent with the cationic synthetic co-polymers of the present invention and apply the two chemicals simultaneously to the tissue sheet.
Additional Softening Agents
[0067] At times it may be advantageous to add additional debonders or softening chemistries to a tissue sheet. Examples of such debonders and softening chemistries are broadly taught in the art. Exemplary compounds include the simple quaternary ammonium salts having the general formula (R 1′ ) 4−b —N + —(R 1″ ) b X − wherein R1′ is a C1-6 alkyl group, R 1 ″ is a C14-C22 alkyl group, b is an integer from 1 to 3 and X— is any suitable counterion. Other similar compounds include the monoester, diester, monoamide and diamide derivatives of the simple quaternary ammonium salts. A number of variations on these quaternary ammonium compounds are known and should be considered to fall within the scope of the present invention. Additional softening compositions include cationic oleyl imidazoline materials such as methyl-1-oleyl amidoethyl-2-oleyl imidazolinium methylsulfate commercially available as Mackernium DC-183 from McIntyre Ltd., located in University Park, Ill. and Prosoft TQ-1003 available from Hercules, Inc. Such softeners may also incorporate a humectant or a plasticizer such as a low molecular weight polyethylene glycol (molecular weight of about 4,000 daltons or less) or a polyhydroxy compound such as glycerin or propylene glycol. While these softeners may be applied to the fibers while in slurry prior to sheet formation, the cationic synthetic co-polymers of the present invention typically provide sufficient debonding and softness improvement so as not to require use of additional bulk softening agents.
[0068] However, it may be particularly advantageous to add such softening agents simultaneously with the cationic synthetic co-polymers of the present invention to a formed tissue sheet at a consistency of about 80% or less. In such situations, dilute solutions of the softening composition and cationic synthetic co-polymer are blended directly and then topically applied to the wet tissue sheet. It is believed in this manner that tactile softness of the tissue sheet and resulting tissue products may be improved due to presence of the additional softening compound. An especially preferred topical softener for this application is polysiloxane. The use of polysiloxanes to soften tissue sheets is broadly taught in the art. A large variety of polysiloxanes are available that are capable of enhancing the tactile properties of the finished tissue sheet. Any polysiloxane capable of enhancing the tactile softness of the tissue sheet is suitable for incorporation in this manner so long as so long as solutions or emulsions of the softener and polysiloxane are compatible, that is when mixed they do not form gels, precipitates or other physical defects that would preclude application to the tissue sheet.
[0069] Examples of suitable polysiloxanes include but are not limited to linear polydialkyl polysiloxanes such as the DC-200 fluid series available from Dow Corning, Inc., Midland, Mich. as well as the organo-reactive polydimethyl siloxanes such as the preferred amino functional polydimethyl siloxanes. Examples of suitable polysiloxanes include those described in U.S. Pat. No. 6,054,020 issued on Apr. 25, 2000 to Goulet et al. and U.S. Pat. No. 6,432,270 issued on Aug. 13, 2002 to Liu et al., the disclosures of which are herein incorporated by reference to the extent that they are non-contradictory herewith. Additional exemplary aminofunctional polysiloxanes are the Wetsoft CTW family manufactured and sold by Wacker Chemie, Munich, Germany.
Miscellaneous Agents
[0070] It may be desirable to treat a tissue sheet with additional types of chemicals. Such chemicals include, but are not limited to, absorbency aids usually in the form of cationic, anionic, or non-ionic surfactants, humectants and plasticizers such as low molecular weight polyethylene glycols and polyhydroxy compounds such as glycerin and propylene glycol.
[0071] In general, the cationic synthetic co-polymers of the present invention may be used in conjunction with any known materials and chemicals that are not antagonistic to its intended use. Examples of such materials and chemicals include, but are not limited to, odor control agents, such as odor absorbents, activated carbon fibers and particles, baby powder, baking soda, chelating agents, zeolites, perfumes or other odor-masking agents, cyclodextrin compounds, oxidizers, and the like. Superabsorbent particles, synthetic fibers, or films may also be employed. Additional options include cationic dyes, optical brighteners, polysiloxanes and the like. A wide variety of other materials and chemicals known in the art of papermaking and tissue production may be included in the tissue sheets of the present invention including lotions and other materials providing skin health benefits.
[0072] The application point for such materials and chemicals is not particularly relevant to the present invention and such materials and chemicals may be applied at any point in the tissue manufacturing process. This includes pre-treatment of pulp, co-application in the wet end of the process, post treatment after drying but on the tissue machine and topical post treatment.
[0073] A surprising aspect of the present invention is that despite use of the hydrophobically modified cationic synthetic co-polymers, the tissue sheets still remain absorbent. The Wet Out Time (hereinafter defined) for treated tissue sheets of the present invention may be about 180 seconds or less, more specifically about 150 seconds or less, still more specifically about 120 seconds or less, and still more specifically about 90 seconds or less. As used herein, the term “Wet Out Time” is related to absorbency and is the time it takes for a given sample of a tissue sheet to completely wet out when placed in water.
Experimental
Basis Weight Determination (Tissue)
[0074] The basis weight and bone dry basis weight of the tissue sheet specimens was determined using a modified TAPPI T410 procedure. As is basis weight samples were conditioned at 23° C.±1° C. and 50±2% relative humidity for a minimum of 4 hours. After conditioning a stack of 16-3″×3″ samples was cut using a die press and associated die. This represents a tissue sheet sample area of 144 in 2 . Examples of suitable die presses are TMI DGD die press manufactured by Testing Machines, Inc., Islandia, N.Y., or a Swing Beam testing machine manufactured by USM Corporation, Wilmington, Mass. Die size tolerances are ±0.008 inches in both directions. The specimen stack is then weighed to the nearest 0.001 gram on a tared analytical balance. The basis weight in pounds per 2880 ft 2 is then calculated using the following equation:
[0000] Basis weight=stack wt. in grams/454*2880
[0075] The bone dry basis weight is obtained by weighing a sample can and sample can lid the nearest 0.001 grams (this weight is A). The sample stack is placed into the sample can and left uncovered. The uncovered sample can and stack along with the sample can lid is placed in a 105° C.±2° C. oven for a period of 1 hour±5 minutes for sample stacks weighing less than 10 grams and at least 8 hours for sample stacks weighing 10 grams or greater. After the specified oven time has lapsed, the sample can lid is placed on the sample can and the sample can is removed from the oven. The sample can is allowed to cool to approximately ambient temperature but no more than 10 minutes. The sample can, sample can lid and sample stack are then weighed to the nearest 0.001 gram (this weight is C). The bone dry basis weight in pounds/2880 ft 2 is calculated using the following equation:
[0000] Bone Dry BW=( C−A )/454*2880
Dry Tensile (Tissue):
[0076] The Geometric Mean Tensile (GMT) strength test results are expressed as grams-force per 3 inches of sample width. GMT is computed from the peak load values of the MD (machine direction) and CD (cross-machine direction) tensile curves, which are obtained under laboratory conditions of 23.0° C.±1.0° C., 50.0±2.0% relative humidity, and after the tissue sheet has equilibrated to the testing conditions for a period of not less than four hours. Testing is conducted on a tensile testing machine maintaining a constant rate of elongation, and the width of each specimen tested was 3 inches. The “jaw span” or the distance between the jaws, sometimes referred to as gauge length, is 2.0 inches (50.8 mm). The crosshead speed is 10 inches per minute (254 mm/min.) A load cell or full-scale load is chosen so that all peak load results fall between 10 and 90 percent of the full-scale load. In particular, the results described herein were produced on an Instron 1122 tensile frame connected to a Sintech data acquisition and control system utilizing IMAP software running on a “486 Class” personal computer. This data system records at least 20 load and elongation points per second. A total of 10 specimens per sample are tested with the sample mean being used as the reported tensile value. The geometric mean tensile is calculated from the following equation:
[0000] GMT=(MD Tensile*CD Tensile) 1/2
[0000] To account for small variations in basis weight, GMT values were then corrected to the 18.5 pounds/2880 ft 2 target basis weight using the following equation:
[0000] Corrected GMT=Measured GMT*(18.5/Bone Dry Basis Weight)
Caliper:
[0077] The term “caliper” as used herein is the thickness of a single tissue sheet, and may either be measured as the thickness of a single tissue sheet or as the thickness of a stack of ten tissue sheets and dividing the ten tissue sheet thickness by ten, where each sheet within the stack is placed with the same side up. Caliper is expressed in microns. Caliper was measured in accordance with TAPPI test methods T402 “Standard Conditioning and Testing Atmosphere For Paper, Board, Pulp Handsheets and Related Products” and T411 om-89 “Thickness (caliper) of Paper, Paperboard, and Combined Board” optionally with Note 3 for stacked tissue sheets. The micrometer used for carrying out T411 om-89 is a Bulk Micrometer (TMI Model 49-72-00, Amityville, N.Y.) or equivalent having an anvil diameter of b 4 1 / 16 inches (103.2 millimeters) and an anvil pressure of 220 grams/square inch (3.3 g kilo Pascals).
Lint and Slough Measurement:
[0078] In order to determine the abrasion resistance, or tendency of the fibers to be rubbed from the tissue sheet when handled, each sample was measured by abrading the tissue specimens via the following method. This test measures the resistance of a material to an abrasive action when the material is subjected to a horizontally reciprocating surface abrader. The equipment and method used is similar to that described in U.S. Pat. No. 4,326,000, issued on Apr. 20, 1982 to Roberts, Jr. and assigned to the Scott Paper Company, the disclosure of which is herein incorporated by reference to the extent that it is non-contradictory herewith. All tissue sheet samples were conditioned at 23° C.±1° C. and 50±2% relative humidity for a minimum of 4 hours. FIG. 8 is a schematic diagram of the test equipment. Shown is the abrading spindle or mandrel 5 , a double arrow 6 showing the motion of the mandrel 5 , a sliding clamp 7 , a slough tray 8 , a stationary clamp 9 , a cycle speed control 10 , a counter 11 , and start/stop controls 12 .
[0079] The abrading spindle 5 consists of a stainless steel rod, 0.5″ in diameter with the abrasive portion consisting of a 0.005″ deep diamond pattern knurl extending 4.25″ in length around the entire circumference of the rod. The abrading spindle 5 is mounted perpendicularly to the face of the instrument 3 such that the abrasive portion of the abrading spindle 5 extends out its entire distance from the face of the instrument 3 . On each side of the abrading spindle 5 is located a pair of clamps 7 and 9 , one movable 7 and one fixed 9 , spaced 4 ″ apart and centered about the abrading spindle 5 . The movable clamp 7 (weighing approximately 102.7 grams) is allowed to slide freely in the vertical direction, the weight of the movable clamp 7 providing the means for insuring a constant tension of the tissue sheet sample over the surface of the abrading spindle 5 .
[0080] Using a JDC-3 or equivalent precision cutter, available from Thwing-Albert Instrument Company, located at Philadelphia, Pa., the tissue sheet sample specimens are cut into 3″±0.05″ wide×7″ long strips (note: length is not critical as long as specimen can span distance so as to be inserted into the clamps A & B). For tissue sheet samples, the MD direction corresponds to the longer dimension. Each tissue sheet sample is weighed to the nearest 0.1 mg. One end of the tissue sheet sample is clamped to the fixed clamp 9 , the sample then loosely draped over the abrading spindle or mandrel 5 and clamped into the sliding clamp 7 . The entire width of the tissue sheet sample should be in contact with the abrading spindle 5 . The sliding clamp 7 is then allowed to fall providing constant tension across the abrading spindle 5 .
[0081] The abrading spindle 5 is then moved back and forth at an approximate 15 degree angle from the centered vertical centerline in a reciprocal horizontal motion against the tissue sheet sample for 20 cycles (each cycle is a back and forth stroke), at a speed of 170 cycles per minute, removing loose fibers from the surface of the tissue sheet sample. Additionally the spindle rotates counter clockwise (when looking at the front of the instrument) at an approximate speed of 5 RPMs. The tissue sheet sample is then removed from the jaws 7 and 9 and any loose fibers on the surface of the tissue sheet sample are removed by gently shaking the tissue sheet sample. The tissue sheet sample is then weighed to the nearest 0.1 mg and the weight loss calculated. Ten tissue sheet specimen per sample are tested and the average weight loss value in mg recorded. The result for each tissue sheet sample was compared with a control sample containing no chemicals. Where a 2-layered tissue sheet sample is measured, placement of the tissue sheet sample should be such that the hardwood portion is against the abrading surface.
Wet Out Time
[0082] The Wet Out Time of a tissue sheet treated in accordance with the present invention is determined by cutting 20 sheets of the tissue sheet sample into 2.5 inch squares. The number of sheets of the tissue sheet sample used in the test is independent of the number of plies per sheet of the tissue sheet sample. The 20 square sheets of the tissue sheet sample are stacked together and stapled at each corner to form a pad of the tissue sheet sample. The pad of the tissue sheet sample is held close to the surface of a constant temperature distilled water bath (23° C.±2° C.), which is the appropriate size and depth to ensure the saturated pad of the tissue sheet sample does not contact the bottom of the water bath container and the top surface of the distilled water of the water bath at the same time, and dropped flat onto the surface of the distilled water, with staple points on the pad of the tissue sheet sample facing down. The time necessary for the pad of the tissue sheet sample to become completely saturated, measured in seconds, is the Wet Out Time for the tissue sheet sample and represents the absorbent rate of the tissue sheet sample. Increases in the Wet Out Time represent a decrease in absorbent rate of the tissue sheet sample.
Softness:
[0083] Softness of tissue sheets and/or tissue products is determined from sensory panel testing. The testing is performed by trained panelists who rub the formed tissue sheets and/or tissue products and compare the softness attributes of the tissue sheets and/or tissue products to the same softness attributes of high and low softness control standards. After comparing these characteristics to the standards, the panelists assign a value for each of the tissue sheets' and/or tissue products' softness attributes. From these values an overall softness of the tissue sheets and/or tissue products determined on a scale from 1 (least soft) to 16 (most soft). The higher the number, the softer the tissue sheet and/or tissue product. In general, a difference of less than 0.5 in the panel softness value is not statistically significant.
EXAMPLES
Example 1
[0084] Example 1 demonstrates the preparation of a blended (non-layered) tissue basesheet. The blended tissue basesheet was made according to the following procedure. About 45.5 pounds (oven dry basis) of eucalyptus hardwood kraft fiber and about 24.5 pounds (oven dry basis) of northern softwood kraft fiber were dispersed in a pulper for about 30 minutes at a consistency of about 3%. The blended thick stock pulp slurry was refined for 10 minutes and then passed to a machine chest where the thick stock pulp slurry was diluted to a consistency of about 1%. Kymene 6500, a commercially available PAE wet strength resin from Hercules, Inc., was added to the pulp slurry in the machine chest at a rate of about 4 pounds of dry chemical per ton of dry fiber. The stock pulp slurry was further diluted to about 0.1 percent consistency prior to forming and deposited from an unlayered headbox onto a fine forming fabric having a velocity of about 50 feet per minute to form a 17″ wide tissue sheet. The flow rate of the stock pulp slurry in the flow spreader was adjusted to give a target sheet basis weight of 12.7 gsm. The stock pulp slurry drained through the forming fabric, building an embryonic tissue sheet. The embryonic tissue sheet was transferred to a second fabric, a papermaking felt, before being further dewatered using a vacuum box to a consistency of between about 15 to about 25%. The tissue sheet was then transferred via a pressure roll to a steam heated Yankee dryer operating at a temperature of about 220° F. at a steam pressure of about 17 PSI. The dried tissue sheet was then transferred to a reel traveling at a speed about 30% slower than the Yankee dryer to provide a crepe ratio of about 1.3:1, thereby providing the blended tissue basesheet.
[0085] An aqueous creping composition was prepared containing about 0.317% by weight of polyvinyl alcohol (PVOH), available under the trade designation of Celvol 523 manufactured by Celanese, Dallas, Tex. (88% hydrolyzed and a viscosity of about 23 to about 27 cps. for a 4% solution at 20° C.); about 0.01% by weight of a PAE resin, available under the trade designation of Kymene 6500 from Hercules, Inc.; and, about 0.001% of a debonder/creping release agent, available under the trade designation of Resozol 2008, manufactured by Hercules, Inc. All weight percentages are based on dry pounds of the chemical being discussed. The creping composition was prepared by adding the specific amount of each chemical to 10 gallons of water and mixing well. PVOH was obtained as a 6% aqueous solution; Kymene 557 as a 12.5% aqueous solution; and, Resozol 2008 as a 7% solution in IPA/water. The creping composition was then applied to the Yankee dryer surface via a spray boom at a pressure of about 60 psi at a rate of about 0.25 g solids/m 2 of product. The finished blended tissue basesheet was then converted into a 2-ply tissue product with the dryer side of each ply facing outward.
Example 2
[0086] Example 2 demonstrates use of a conventional wet end debonder for preparing soft tissue products. The blended tissue basesheet used in this example was made in general accordance with Example 1. The Prosoft TQ-1003 was diluted to 1% solids with water prior to addition to the machine chest. The diluted Prosoft TQ-1003, a cationic oleylimidazoline debonder, commercially available from Hercules, Inc. was added to the machine chest. The machine chest was then allowed to stir for about 5 minutes prior to start of the tissue sheet formation. The amount of debonder to total tissue basesheet fiber on a dry weight basis was about 0.1%. The finished blended tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side of each ply facing outward.
Example 3
[0087] Example 3 demonstrates use of a conventional wet end debonder for preparing soft tissue products. The blended tissue basesheet used in this example was made in general accordance with Example 1. The Prosoft TQ-1003 was diluted to about 1% solids with water prior to addition to the machine chest. The diluted Prosoft TQ-1003, a cationic oleylimidazoline debonder, commercially available from Hercules, Inc. was added to the machine chest. The machine chest was then allowed to stir for about 5 minutes prior to start of the tissue sheet formation. The amount of debonder to total tissue basesheet fiber on a dry weight basis was about 0.2%. The finished blended tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side of each ply facing outward.
Example 4
[0088] Example 4 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, blended tissue basesheet prior to drying the blended tissue basesheet. The blended tissue basesheet used in this example was prepared in general accordance with Example 1. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % of n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The blended tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.1%. The finished blended tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side of each ply facing outward.
Example 5
[0089] Example 5 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, blended tissue basesheet prior to drying the blended tissue basesheet. The blended tissue basesheet used in this example was prepared in general accordance with Example 1. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % of n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The blended tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total sheet fiber on a dry weight basis was about 0.2%. The finished blended tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side of each ply facing outward.
Example 6
[0090] Example 6 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, blended tissue basesheet prior to drying the blended tissue basesheet. The blended tissue basesheet used in this example was prepared in general accordance with Example 1. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % of n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The blended tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.4%. The finished blended tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side of each ply facing outward.
[0091] Table 1 summarizes the data for Examples 1-6. FIG. 1 shows graphically the relationship between slough and tensile. Both Table 1 and FIG. 1 demonstrate the cationic synthetic co-polymers of the present invention simultaneously reducing slough and strength when applied topically to a wet, formed tissue sheet. Furthermore, the softness data shown in Table 3 and graphically in FIG. 2 shows that the tissue products treated with the cationic synthetic co-polymers of the present invention follow the same strength/softness technology curve as the standard cationic oleylimidazoline debonder. Hence, the tissue products that have lower slough at equivalent softness are obtained as shown in FIG. 3 . Also given in a Table 1 are wet-out times showing that the tissue products of the present invention retain their absorbent properties.
[0000]
TABLE 1
Amount % of
Wet-out
Slough,
Example
Additive
Dry Fiber
time, s
mg
GMT
1
None
0
16
1.8
717
2
Prosoft TQ-1003
0.1%
3
4.8
346
3
Prosoft TQ-1003
0.2%
3
7.6
232
4
Invention
0.1%
13
2.0
496
5
Invention
0.2%
18
1.3
433
6
Invention
0.4%
18
1.2
441
Example 7
[0092] Example 7 demonstrates the preparation of a layered tissue basesheet. About 70 pounds, oven dried basis, of eucalyptus hardwood kraft pulp fibers were dispersed in a pulper for about 30 minutes, forming an eucalyptus hardwood pulp kraft fiber slurry having a consistency of about 3%. The Eucalyptus pulp hardwood kraft fiber slurry was then transferred to two machine chests and diluted to a consistency of about 0.5 to about 1%. About 70 pounds, oven dry basis, of LL-19 northern softwood kraft pulp fibers were dispersed in a pulper for about 30 minutes, forming a northern softwood kraft pulp fiber slurry having a consistency of about 3%. A low level of refining was applied for about 12 minutes to the softwood kraft pulp fibers. After dispersing, the northern softwood kraft pulp fibers to form the slurry, the northern softwood kraft pulp fibers were passed to a machine chest and diluted to a consistency of between about 0.5 to about 1%.
[0093] Kymene 6500, a commercially available PAE wet strength resin from Hercules, Inc., was added to both the eucalyptus hardwood and northern softwood kraft pulp slurries in the machine chest at a rate of about 4 pounds of dry chemical per ton of dry fiber. The stock pulp fiber slurries were further diluted to approximately about 0.1 percent consistency prior to forming and deposited from a three layered headbox onto a fine forming fabric having a velocity of about 50 feet per minute to form a 17″ wide tissue sheet. The flow rates of the stock pulp fiber slurries into the flow spreader were adjusted to give a target sheet basis weight of about 12.7 gsm and a layer split of 35% Eucalyptus hardwood kraft pulp fibers on both outer layers and 30% LL-19 northern softwood kraft pulp fibers in the center layer. The stock pulp fiber slurries were drained on the forming fabric, building a layered embryonic tissue sheet. The embryonic tissue sheet was transferred to a second fabric, a papermaking felt, before being further dewatered with a vacuum box to a consistency of between about 15 to about 25%. The embryonic tissue sheet was then transferred via a pressure roll to a steam heated Yankee dryer operating at a temperature of about 220° F. at a steam pressure of about 17 PSI. The dried tissue sheet was then transferred to a reel traveling at a speed about 30% slower than the Yankee dryer to provide a crepe ratio of about 1.3:1, thereby providing the layered tissue basesheet.
[0094] An aqueous creping composition was prepared containing about 0.317% by weight of polyvinyl alcohol (PVOH), available under the trade designation of Celvol 523 manufactured by Celanese (88% hydrolyzed with a viscosity of about 23 to about 27 cps. for a 4% solution at 20° C.); about 0.01% by weight of a PAE resin, available under the trade designation of Kymene 6500 from Hercules, Inc.; and, about 0.001% of a debonder/creping release agent, Resozol 2008, manufactured by Hercules, Inc. All weight percentages are based on dry pounds of the chemical being discussed. The creping composition was prepared by adding the specific amount of each chemical to 10 gallons of water and mixing well. PVOH was obtained as a 6% aqueous solution; Kymene 557 as a 12.5% aqueous solution; and, Resozol 2008 as a 7% solution in IPA/water. The creping composition was then applied to the Yankee dryer surface via a spray boom at a pressure of about 60 psi at a rate of about 0.25 g solids/m 2 of product. The finished layered basesheet was then converted into a 2-ply tissue product with the dryer side layer of each ply facing outward. See Table 4 showing physical properties of blended tissue basesheets. GMT was normalized to the basis weight of the untreated tissue sheet.
Example 8
[0095] Example 8 demonstrates use of a conventional wet end debonder for preparing soft tissue products. The layered tissue basesheet used in this example was made in general accordance with Example 7. The Prosoft TQ-1003 was diluted to about 1% solids with water prior to addition to the machine chest. The diluted Prosoft TQ-1003, a cationic oleylimidazoline debonder, commercially available from Hercules, Inc. was added to the machine chest containing the eucalyptus hardwood kraft pulp fiber slurry going to the layer that would come into contact with the dryer. The machine chest was then allowed to stir for about 5 minutes prior to start of the tissue sheet formation. The amount of debonder relative to total dried fiber of the tissue basesheet was about 0.025%. The finished layered tissue basesheets were then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 9
[0096] Example 9 demonstrates use of a conventional wet end debonder for preparing soft tissue products. The layered tissue basesheet used in this example was made in general accordance with Example 7. The Prosoft TQ-1003 was diluted to about 1% solids with water prior to addition to the machine chest. The diluted Prosoft TQ-1003, a cationic oleylimidazoline debonder, commercially available from Hercules, Inc. was added to the machine chest containing the eucalyptus hardwood kraft pulp fiber slurry going to the layer that would come into contact with the dryer. The machine chest was then allowed to stir for about 5 minutes prior to start of the tissue sheet formation. The amount of debonder to total tissue basesheet fiber on a dry weight basis was about 0.05%. The finished layered tissue basesheets were then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 10
[0097] Example 10 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, layered tissue basesheet prior to drying the layered tissue basesheet. The layered tissue basesheet used in this example was prepared in general accordance with Example 7. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the layered tissue basesheet that is later brought into contact with the Yankee dryer. The layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.1%. The finished layered tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 11
[0098] Example 11 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, layered tissue basesheet prior to drying the layered tissue basesheet. The layered tissue basesheet used in this example was prepared in general accordance with Example 7. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the layered tissue basesheet that is later brought into contact with the Yankee dryer. The layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.2%. The finished layered tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 12
[0099] Example 12 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, layered tissue basesheet prior to drying the layered tissue basesheet. The layered tissue basesheet used in this example was prepared in general accordance with Example 7. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the layered tissue basesheet that is later brought into contact with the Yankee dryer. The layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.4%. The finished layered tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 13
[0100] Example 13 demonstrates the topical application of cationic synthetic co-polymer of the present invention to a wet, layered tissue basesheet prior to drying the layered tissue basesheet. The layered tissue basesheet used in this example was prepared in general accordance with Example 7. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer of the present invention containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the layered tissue basesheet that is later brought into contact with the Yankee dryer. The layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.8%. The finished layered tissue basesheet was then converted into a 2-ply facial tissue product with the dryer side layer of each ply facing outward.
[0101] Table 2 summarizes the data for Examples 7-12. FIG. 1 shows graphically the relationship between slough and tensile. Both Table 2 and FIG. 1 demonstrate the cationic synthetic co-polymers of the present invention simultaneously reducing slough and strength when applied topically to a wet, formed tissue sheet. Furthermore, the softness data shown in Table 3 and graphically in FIG. 2 shows that the tissue products treated with the cationic synthetic co-polymers of the present invention follow the same strength/softness technology curve as the standard cationic oleylimidazoline debonder. Hence, tissue products that have lower slough at equivalent softness are obtained as shown in FIG. 3 . Also given in Table 2 are wet-out times showing that the tissue products of the present invention retain their absorbent properties.
[0000]
TABLE 2
Amount % of
Total Sheet
Wet-out
Slough,
Example
Additive
Dry Fiber
time, s
mg
GMT
7
None
0
18
2.3
753
8
Prosoft TQ-1003
0.025%
6
6.3
594
9
Prosoft TQ-1003
0.05%
5
5.0
544
10
Invention
0.1%
18
2.2
627
11
Invention
0.2%
17
3.0
660
12
Invention
0.4%
18
2.3
652
13
Invention
0.8%
23
1.2
602
[0102] Softness testing was completed on Examples 1-13. The data is shown in table 3 and plots of tensile vs. softness are shown graphically in FIG. 2 for both blended and layered sheets. As seen in FIG. 2 , the cationic synthetic co-polymers of the present invention provide equivalent softness to the standard debonders known in the art but also provide for lower slough products. This benefit is seen independent of the particular sheet structure employed. Hence, as FIG. 3 shows, it is possible to make equivalently soft tissue products that advantageously have lower lint and slough by employing the cationic synthetic co-polymers of the present invention. Again, this effect is independent of the particular tissue sheet structure that may be employed.
[0000]
TABLE 3
Amount % of
Total Sheet
Slough,
Example
Additive
Dry Fiber
mg
GMT
Softness
1
None
0
1.8
717
7.7
2
Prosoft TQ-1003
0.1%
4.8
346
8.3
3
Prosoft TQ-1003
0.2%
7.6
232
8.6
4
Invention
0.1%
2.0
496
8.1
5
Invention
0.2%
1.3
433
8.2
6
Invention
0.4%
1.2
441
8.2
7
None
0
2.3
753
8.1
8
Prosoft TQ-1003
0.025%
6.3
594
8.5
9
Prosoft TQ-1003
0.05%
5.0
544
8.4
10
Invention
0.1%
2.2
627
8.4
11
Invention
0.2%
3.0
660
8.4
12
Invention
0.4%
2.3
652
8.3
13
Invention
0.8%
1.2
602
8.3
[0103] Examples 14-19 compare the use of an anionic hydrophobically modified acrylate polymer and the cationic synthetic co-polymers of the present invention in a 2-layer, 2-ply facial tissue product.
Example 14
[0104] Example 14 demonstrates the preparation of a 2-layered tissue basesheet. The 2-layered tissue basesheet was made in general accordance with the procedure outlined in Example 7 with the exception that a 2-layered tissue basesheet used in this example was formed consisting of a layer which contacted the surface of the Yankee dryer containing 65% of the total sheet weight of eucalyptus hardwood kraft pulp fibers and a felt (air side) layer containing 35% total sheet weight of LL-19 northern softwood kraft pulp fibers. The finished 2-layered tissue basesheet was then converted into a 2-layer, 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 15
[0105] Example 15 demonstrates the topical application of cationic synthetic co-polymers of the present invention to a wet, 2-layered tissue basesheet prior to drying the 2-layered tissue basesheet. The 2-layered tissue basesheet used in this example was prepared in general accordance with Example 14. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The 2-layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.5%. The finished 2-layered tissue basesheet was then converted into a 2-layer, 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 16
[0106] Example 16 demonstrates the topical application of cationic synthetic co-polymers of the present invention to a wet, 2-layered tissue basesheet prior to drying the 2-layered tissue basesheet. The 2-layered tissue basesheet used in this example was prepared in general accordance with Example 14. A 30% by weight aqueous dispersion of a cationic synthetic co-polymer containing 80 mole % n-butyl acrylate and 20 mole % of [2-(methacryloyloxy)ethyl] trimethyl ammonium chloride was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The 2-layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersion. No changes were required to the creping adhesive package and no felt plugging or other process issues were encountered with application of the cationic synthetic co-polymer. The amount of cationic synthetic co-polymer to total tissue basesheet fiber on a dry weight basis was about 1.0%. The finished 2-layered tissue basesheet was then converted into a 2-layer, 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 17
[0107] Example 17 demonstrates the topical application of a hydrophobically modified anionic co-polymer to a wet, 2-layered tissue basesheet prior to drying the 2-layered tissue basesheet. The 2-layered tissue basesheet used in this example was prepared in general accordance with Example 14. A 30% by weight aqueous dispersion of a hydrophobically modified anionic co-polymer containing 60 mole % acrylic acid; 24.5 mole % n-butylacrylate; 10.5 mole % 2-ethylhexylacrylate; and, 5 mole % AMPS wherein the AMPS was converted to the sodium salt was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The 2-layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted hydrophobically modified anionic co-polymer dispersion. Significant issues were encountered with crush and holes in the 2-layered tissue basesheet when using the anionic co-polymer. The amount of anionic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.15%. The finished 2-layered tissue basesheet was then converted into a 2-layer, 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 18
[0108] Example 18 demonstrates the topical application of a hydrophobically modified anionic co-polymer to a wet, 2-layered tissue basesheet prior to drying the 2-layered tissue basesheet. The 2-layered tissue basesheet used in this example was prepared in general accordance with Example 14. A 30% by weight aqueous dispersion of a hydrophobically modified anionic co-polymer containing 60 mole % acrylic acid; 24.5 mole % n-butylacrylate; 10.5 mole % 2-ethylhexylacrylate; and, 5 mole % AMPS wherein the AMPS was converted to the sodium salt was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The 2-layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted hydrophobically modified anionic co-polymer dispersion. Significant issues were encountered with crush and holes in the 2-layered tissue basesheet when using the anionic co-polymer. The amount of anionic co-polymer to total tissue basesheet fiber on a dry weight basis was about 0.25%. The finished 2-layered tissue basesheet was then converted into a 2-layer, 2-ply facial tissue product with the dryer side layer of each ply facing outward.
Example 19
[0109] Example 19 demonstrates the topical application of a hydrophobically modified anionic co-polymer to a wet, 2-layered tissue basesheet prior to drying the 2-layered tissue basesheet. The 2-layered tissue basesheet used in this example was prepared in general accordance with Example 14. A 30% by weight aqueous dispersion of a hydrophobically modified anionic co-polymer containing 60 mole % acrylic acid; 24.5 mole % n-butylacrylate; 10.5 mole % 2-ethylhexylacrylate; and, 5 mole % AMPS wherein the AMPS was converted to the sodium salt was diluted with water and sprayed onto the side of the tissue basesheet that is later brought into contact with the Yankee dryer. The 2-layered tissue basesheet had a consistency, at this point, of between about 10% and about 20%. The aqueous dispersion was sprayed through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted hydrophobically modified anionic co-polymer dispersion. Significant issues were encountered with crush and holes in the 2-layered tissue basesheet when using the anionic co-polymer. The amount of anionic polymer to total sheet fiber on a dry weight basis was about 0.50%. Significant issues with felt plugging and crush were encountered such that it was not possible to transfer the sheet to the Yankee dryer and no product could be obtained.
[0110] Furthermore, as Table 4 shows, the anionic co-polymer used in Examples 17-19 did not reduce slough and tensile as did the cationic synthetic co-polymer used in Examples 15-16. The tensile reduction seen in Example 18 is most likely due to the large number of holes in the sheet and not representative of a debonding effect. The 2-layered tissue basesheet treated in accordance with Example 19 could not be transferred to the Yankee dryer and wound due to the extremely poor quality of the tissue basesheet.
[0000]
TABLE 4
Amount %
Wet-out
Slough,
Example
Additive
of Dry Fiber
time, s
mg
GMT
14
None
0
4
7.2
631
15
Cationic, invention
0.5%
12
5.6
610
16
Cationic, invention
1.0%
21
4.8
550
17
Anionic
0.15%
5
11.6
661
18
Anionic
0.25%
10
7.3
577
19
Anionic
0.50%
Could not make sheet
Examples 20-28
[0111] Examples 20-28 demonstrate the applicability of the present invention using a number of different cationic synthetic co-polymers. Additionally, these examples demonstrate ability to use the cationic synthetic co-polymers of the present invention in conjunction with other cationic papermaking additives. In Examples 20-28, the layered tissue basesheets used were made in general accordance with Examples 7-13. A cationic glyoxylated polyacrylamide, available under the trade designation of Parez 631NC manufactured by Bayer, Inc., Suffolk, Va., was added to the LL-19 softwood kraft pulp fibers in the machine chest at a level of about 5 pounds of dry solids of the chemical per ton of dry LL-19 softwood kraft pulp fibers. A commercially available cationic polyamide epichlorohydrin wet strength resin, Kymene 6500 available from Hercules, Inc. was added to both the northern softwood kraft pulp fibers and the eucalyptus hardwood kraft pulp fibers in the machine chest at a level of about 4 pounds of dry solids of the chemical per ton of dry fiber. The cationic synthetic co-polymers were applied as aqueous dispersions via spraying through two nozzles (commercially available under the designation 650017 from Spraying Systems Co., Wheaton, Ill.) at about 60 psi for a total addition rate of about 180 mL/min. Addition levels were controlled by adjusting the concentration of the diluted cationic synthetic co-polymer dispersions. In each example, the layered tissue basesheets were converted into 2-ply facial tissue products with the dryer side layer of each ply facing outward as with all previous examples.
[0112] For Examples 21-23, a standard cationic oleylimidazoline debonder, available under the designation of Prosoft TQ-1003 manufactured by Hercules, Inc., was added to the northern softwood kraft pulp fibers going to the layer of the tissue basesheet in each example that is later brought into contact with the Yankee dryer. The debonder was added to the machine chest as about 1% aqueous emulsion and allowed to stir for about 5 minutes prior to forming the tissue basesheet for each example.
[0000]
TABLE 5
Chemical
Composition
I
89.9 mole % Ethyl Acrylate, 0.1 mole % Methyl
Methacrylate,10 mole % [2-(methacryloyloxy)ethyl]
trimethyl ammonium chloride
II
89.9 mole % Ethyl Acrylate, 0.1 mole % Methyl
Methacrylate, 10 mole %
2-[(acryloyloxy)ethyl]trimethylammonium chloride
III
74.9 mole % Ethyl Acrylate, 0.1 mole % Methyl
Methacrylate, 25 mole %
2-[(acryloyloxy)ethyl]trimethylammonium chloride
IV
80 mole % Butyl Acrylate, 20% mole %
[2-(methacryloyloxy)ethyl] trimethylammonium methosulfate
[0113] Specific chemical compositions of the cationic synthetic co-polymers used in Examples 24-27 are shown in Table 5. The chemical compositions I-III were prepared via an emulsion polymerization process using a non-ionic surfactant. The chemical compositions I-III were delivered as between about 25% to about 35% solids aqueous emulsions. The chemical composition IV was prepared via a solvent displacement process and was delivered as a 30% solids aqueous dispersion containing no surfactants. The physical test results are shown in Table 6. Example 28 is a control sample used to determine impact of water spraying alone on the tissue basesheet. As Example 28 demonstrates, the effects seen in the tissue basesheet, and ultimately the facial tissue products made from the tissue basesheets, wherein the cationic synthetic co-polymers of the present invention was used, are related to application of the cationic synthetic co-polymer and not a function of the water.
[0000]
TABLE 6
Amount % of
Total Sheet Dry
Wet-out
Example
Additive
Fiber
time, s
Slough, mg
GMT
Softness
20
None
0
6
3.5
1160
6.9
21
Prosoft TQ-1003
0.05%
5
3.9
1026
7.2
22
Prosoft TQ-1003
0.15%
3
7.8
747
7.8
23
Prosoft TQ-1003
0.20%
3
6.8
635
8.0
24
III
0.40%
10
2.0
1124
7.0
25
II
0.40%
21
2.3
842
7.6
26
I
0.40%
22
2.1
733
7.6
27
IV
0.20%
23
2.3
772
7.4
28
Water
7
4.1
1052
7.0
[0114] The data is shown graphically in FIGS. 4 and 5 . As with the previous examples, the cationic synthetic co-polymers of the present invention show significantly less slough increase with decreased tensile than the standard oleylimidazoline debonder. FIG. 5 shows that the facial tissue products made using the cationic synthetic co-polymers of the present invention display lower slough at a given level of softness.
Examples 29-34
[0115] In Examples 29-34, all examples used a layered basesheet made in general accordance with Examples 7-13 with the exception that no refining was done to the eucalyptus hardwood kraft pulp fibers. A cationic glyoxylated polyacrylamide, available under the designation of Parez 631NC manufactured by Bayer, Inc., was added to the LL-19 softwood kraft pulp fibers in the machine chest at a level of about 10 pounds of dry solids of the chemical per ton of the dry LL-19 softwood kraft pulp fibers. A cationic polyamide epichlorohydrin wet strength resin, available under the designation of Kymene 6500 manufactured by Hercules, Inc. was added to both the northern softwood kraft pulp fibers and the eucalyptus hardwood kraft pulp fibers in the machine chest at a level of about 4 pounds of dry solids of the chemical per ton of dry kraft pulp fiber. The cationic acrylate polymers and debonders were added to the Eucalyptus hardwood kraft fibers in the machine chest going to the layer of the tissue basesheets that is later brought into contact with the Yankee dryer. Specific chemical compositions of the cationic synthetic co-polymers used in Examples 31-34 are given in Table 7.
[0000]
TABLE 7
Chemical
Composition
V
95 mole % methyl acrylate, 5 mole % [2-(acryloyloxy)ethyl]
trimethyl ammonium chloride
VI
80 mole % N-butyl acrylate, 20 mole %
[2-(methacryloyloxy)ethyl] trimethyl ammonium chloride
[0116] The slough, tensile, and softness results are shown in Table 8 and graphically presented in FIGS. 6 and 7 . Relative to the control debonders, the cationic synthetic co-polymers of the present invention show significantly less slough formation. As with the other examples, tissue basesheets made using the cationic synthetic co-polymers of the present invention show less slough generation at a given tensile than the standard debonders.
[0000]
TABLE 8
Weight % of
Dry Fiber
in Dryer
Wet-out
Slough,
Example
Additive
Layer
time, s
mg
GMT
Softness
29
Prosoft
0.10%
2.9
7.6
605
8.2
TQ-1003
30
Prosoft
0.15%
2.8
8.1
495
8.3
TQ-1003
31
V
0.25%
22
2.2
629
8.0
32
V
0.50%
50.6
4.1
548
8.1
33
VI
0.25%
38.4
5.1
581
8.1
34
VI
0.50%
103.9
5.7
459
8.3
[0117] The results show that it is possible to reduce slough at equivalent or lower GMT by applying the cationic synthetic co-polymers of the present invention to a fiber slurry prior to formation of the tissue sheet. | The present invention is a soft tissue sheet having reduced lint and slough. The tissue sheet comprises papermaking fibers and a synthetic co-copolymer. The synthetic co-polymer has the general structure:
wherein R 1 , R 2 , R 3 are independently selected from a group consisting of: H; C 1-4 alkyl radicals; and, mixtures thereof; R 4 is selected from a group consisting of C 1 -C 8 alkyl radicals and mixtures thereof; Z 1 is a bridging radical attaching the R 4 functionality to the polymer backbone; and, Q 1 is a functional group containing at least a cationic quaternary ammonium radical. w, x, y≧1 and the mole ratio of x to (x+y) is about 0.5 or greater. | 3 |
TECHNICAL FIELD
This invention relates to a technique for accomplishing Built-In Self-Testing of a ring-address FIFO to detect memory faults, addressing faults and functional faults.
Background Art
First-In First-Out memories (FIFOs) are used in a variety of electronic circuits for buffering data transferred between a pair of circuits that operate at different clock rates. Generally, there are two types of FIFOs. The first type of FIFO is the shift register type that uses a self-clocking register for shifting data from a write port to a read port. The second type of FIFO utilizes a Random Access Memory (RAM) as its storage element, rather than a shift register. The RAM within the RAM-type FIFO may have a single (combined) read/write port or separate (dual) ports for reading and writing data, the latter being more popular. The most common type of dual-port RAM-type FIFO utilizes a ring-type addressing mechanism comprised of a pair of n-bit shift registers (where n is an integer, corresponding to the number of storage rows in the RAM). Each shift register is associated with one of the read and write ports, respectively, of the RAM and operates to sequentially address the RAM so that a B-bit word may be read from, or written to the addressed storage location, respectively.
From a reliability standpoint, it is desirable to test all aspects of the ting-address FIFO. In the past, FIFOs have been tested by parametric, functional and asynchronous tests. However, such tests do not reliably detect all possible faults, including faults associated with the memory, the addressing mechanism, and the overall functionality of the FIFO. While fault models and tests have been described in the literature for detecting faults in RAMs, no fault-model tests have been described for testing the dual-port ring-address FIFO.
Thus, there is a need for a technique to detect memory, address and functional faults that may occur in a dual-port RAM-type ring address FIFO.
Brief Summary of the Invention
Briefly, in accordance with the invention, a method is provided for testing a dual-port RAM-type ring-address FIFO to detect memory, address and functional faults. The method is practiced by causing the FIFO to execute a first sequence of operations, including a first set of functional operations. The first sequence of operations, when executed, causes the FIFO to manifest certain functional faults when present. Following the first operation sequence, the FIFO executes a second sequence of operations. The second sequence of operations, when executed, detects a second set of functional faults, including faults associated with the re-transmit and reset function of the FIFO. Next, the FIFO executes a third sequence of operations. The third sequence of operations detects a third set of functional faults, a first set of memory faults, and a first set of address faults. The fourth sequence of operations detects a second set of addressing faults and a second set of memory faults. The first and second sets of addressing faults comprise the entire set of potential addressing faults while the first and second sets of memory faults comprise all of the potential memory faults. By executing the first, second, third and fourth sequences of operations, all of the potential memory, address and functional faults of the FIFO are detected.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block schematic diagram of a prior-art ting-address FIFO having a dual-port RAM as its memory element;
FIG. 2 is a block schematic diagram of a portion of the FIFO of FIG. 1 showing the manner in which the RAM is addressed;
FIG. 3 is a table illustrating the steps of a method, in accordance with a first embodiment of the invention, for testing the FIFO of FIG. 1;
FIG. 4 is a block schematic diagram of a ring-address FIFO in accordance with another aspect of the invention; and
FIG. 5 is a table illustrating the steps of a method in accordance with a second embodiment of the invention for testing the FIFO of FIG. 4.
DETAILED DESCRIPTION
FIG. 1 illustrates a prior-art, dual-port RAM-type ring-address, First-In First-Out (FIFO) memory device 100 comprised of a Random Access Memory (RAM) 102 that has n storage rows (where n is an integer), each row storing a word B bits wide (where B is also an integer). The RAM 102 has separate input and output ports 104 and 106, respectively, through which data is written to, and read from, respectively, the RAM. The input port 104 of the RAM 102 is coupled to a data input register 108 that acts as a buffer to temporarily store incoming data supplied on a Data Input (DI) line before such data is supplied to the RAM input port. The RAM output port 106 is coupled to a data output register 110 that buffers outgoing data from the RAM 102 before such data is placed on a Data Output (DO) line.
The FIFO 100 further includes a Write Address Register (WAR) 112 and a Read Address Register (RAR) 114, each n bits wide. Referring to FIG. 2, both the WAR 112 and the RAR 114 contain a pattern of n-1 "0s" and a single "1". The position of the "1" in the pattern stored in the WAR 112 and in the RAR 114 corresponds to the particular word in the RAM 102 addressed by the WAR and RAR, respectively. For example, when a "1" is present in the i+2 position of the WAR 112, then the WAR addresses the i+2 word in the RAM 102.
Referring to FIG. 1, the FIFO 100 also includes a control block 116, typically a state machine, for controlling the operation of the FIFO in response to a set of externally-supplied signals. The externally supplied signals include a Write Enable (WE) and a Read Enable (RE) signal for controlling the WAR 112 and RAR 114, respectively. When the WE and RE signals are asserted at a logic "1" level, the control block 116 causes the WAR 112 and RAR 114, respectively, to be incremented to address the next successive location in the RAM 102 that is to be written to, and read from, respectively. A Write Clock (WCK) signal and a Read Clock (RCK) signal are also input to the control block 116 to cause the control block to clock the data input register 108 and the data output register 110, respectively, to write data to, and to read data from, respectively, the RAM 102. The control block 116 is also responsive to externally supplied Reset (RS) and Re-Transmit (RT) signals. Upon receipt of the RS signal, the control block 116 brings the FIFO 100 to its initial state by resetting the WAR 112 and the RAR 114 so both registers address the first word of the RAM 102, stored at an Initial Address (IA)of 1,0,0 . . . . 0. Upon receipt of the RT signal, the control block 116 resets the RAR 114 so that the RAR now addresses the first word of the RAM 102.
The control block 116 not only controls the operation of the FIFO 100 but also generates certain signals (flags) indicative of the operation of the FIFO. For example, the FIFO generates a Full FIFO (FF) flag and an Empty FIFO (EF) flag. The FF flag is set to a logic high or "1" level when the RAM 102 is full (i.e., the RAM contains n unread words). Conversely, the FF flag is set to logic low or "0" level when the FIFO 100 is not full (i.e., one or more of the n words in the FIFO 100 has been read.) The EF flag is set to a logic high or "1" level when the FIFO 100 contains zero words (i.e., all of n words in the RAM 102 have been read. ) The EF flag is set to a logic low or "0" level when the FIFO 100 is not empty. Typically, the control block 116 utilizes the status of the FF and EF flags to afford the FIFO 100 Over-Write Protection (OWP) and Over-Read Protection (ORP), respectively. When the FF flag is at a logic high or "1" level, then the control block 116 prevents the occurrence of a Write Operation (WO) while allowing such an operation when FF=0. In a similar fashion, the control block 116 prevents the occurrence of a Read Operation (RO) when the EF flag is at a logic high or "1" level while permitting a RO when EF=0. In addition to the flags FF and EF, the control block 116 generates a Write Acknowledge (WAck) flag and a Read Acknowledge (RAck) flag when a WO and a RO, respectively, have occurred. The FIFO 100 may experience a variety of faults. For instance, the FIFO 100 may experience memory faults associated with the RAM 102. Such memory faults may include:
1. a Stuck-At Fault (SAF) characterized by the presence of a logic "1" or "0" in a memory location in the RAM 102 notwithstanding the fact that a "0" or a "1", respectively, had been previously written to that location;
2. a Stuck-Open Fault (SOF) characterized by an open read or write line to each storage location so that the value read from the RAM corresponds to a previously written value rather than its current value;
3. a Transition Fault (TF) characterized by the failure of the value of a bit stored in the RAM 102 to transition from a logic "1" to a logic "0" (or vice versa) following a pair of WOs during which a logic "1" and a logic "0", respectively, (or a logic "0" and logic "1 ", respectively,) were written;
4. Coupling faults (CFin, CFid and CFst) characterized by inversion, indepotent and state coupling, respectively, of a bit stored in the RAM 102;
5. a Data Retention Fault (DRF) characterized by the loss of a data value stored in a memory bit in the RAM 102 over time;
6. Linked Coupling Faults, characterized by the simultaneous occurrence of two coupling faults and Linked Transition and Coupling Faults, characterized by the simultaneous presence of a linked fault and a coupling fault, (these two types of faults collectively identified by the term (LF)); and
7. Multi-Port Faults (MPF) characterized by faults associated with the mechanism within each storage location that allows for accessing via multiple input and output ports.
In addition to the above-described memory faults, the FIFO 100 may also experience a fault in addressing the words stored in the RAM 102. Such faults, hereinafter referred to as Address Faults (AF), can be classified in four categories:
1. AF-I The address faults in category I manifest themselves when, after at most n increments, the contents in either the WAR 112 or the RAR 114 remains all "0s";.
2. AF-II The address faults in category II manifest themselves when, after at most n-1 increments, the contents of the WAR 112 or RAR 114 contains more than a single "1";
3. AF-III The address faults in category III manifest themselves by all "0s" rather than one or two specific addresses; and
4. AF-IV The address hulls in category IV manifest themselves by two separate addresses.
Lastly, the FIFO 100 may also experience functional faults as a result of an inability to perform one or more of its above-described functions and/or an inability to generate proper values for the flags FF, EF, WAck and RAck. The FIFO 100 is also deemed to be faulty if the FIFO is able to perform a WO and a RO when the FIFO is full and empty, respectively.
In accordance with the invention, a method has been provided for testing the FIFO 100 to detect potential memory faults, address faults, and functional faults by causing the FIFO to execute several sequences of functional operations, read operations and write operations. The steps of the method are illustrated in tabular form in FIG. 3. As seen in that figure, the method comprises thirty-one separate steps, labeled (1)-(31) that have been grouped in four sequences I-IV.
Prior to actually initiating testing, the FIFO 100 of FIG. 1 is cleared so that the flags FF and EF are at a logic low or "0" level and a logic high or "1" level, respectively. The first operation sequence is commenced by executing Step (1), whereupon a Reset (RS) operation is initiated to cause the FIFO 100 to be reset so that the WAR 112 and the RAR 114 (both of FIG. 1) each address the IA, thereby addressing the first word in the RAM 102 of FIG. 1. Next, step (2) of FIG. 3 is executed and an active (i.e., a logic "1" or high level) Read Clock (RCK) signal and an active Read Enable (RE) signal are supplied to the control block 116 of FIG. 1 to cause the RAM 102 to commence a Read Operation (RO). If the FIFO 100 is operating properly, then the RO should fail because of the Over-Read Protection (ORP) feature of the FIFO. If the Read Acknowledge (RAck) flag is set, then a fault exists with either the flag itself, or with the ORP feature of the FIFO 100.
Step (3) is executed after step (2),whereupon an active Write Clock signal (WCK) and an inactive (logic low or "0" level) Write Enable signal (WE) are supplied to the control block 116 of FIG. 1. Even though the WCK signal is active, the RAM 102 of FIG. 2, unless faulty, should not commence a WO while the signal WE is inactive. Therefore, the Write Acknowledge flag (WAck) should not be set at this time. Thus, by monitoring the WAck flag, a fault associated with that flag and/or with the WE signal, can be detected during step (3).
After step (3), step (4) is executed, whereupon a WO is commenced to write a word of all zeros in the first storage location in the RAM 102 of FIG. 2. (The WO is commenced upon the assertion of an active WCK signal and an active WE signal.) Upon execution of the WO during step (4), the flag WAck should now be set to indicate that a WO did indeed occur. Moreover, the Empty FIFO flag (EF) should no longer be set because the FIFO 100 should no longer be empty if the WO was executed successfully. After step (4), step (5) is executed, whereupon an active Read Clock (RCK) signal and an inactive Read Enable (RE) signal are supplied to the control block 116 of FIG. 1. While the RE signal is inactive, the control block 116 should not initiate a RO unless there is a fault. Thus, the Read Acknowledge (RAck) flag should not be set at this time. If the RAck flag has been set, then either the flag itself is faulty, and/or there is some fault associated with the RE signal.
Following step (5), step (6) is executed and a RO is executed to determine if a word of all "0s" has been written at the first location of the RAM 102 during the previous WO. (The RO during step (6) is commenced by asserting an active RCK signal and an active RE signal.) If the RO has been successfully executed during step (6), the RAck flag should now be set. Further, if the RO has been successfully executed, then the Empty FIFO (EF) flag should also be set because the FIFO 100 of FIG. 1 should now be empty (i.e., all of the words previously written in the RAM 102 of FIG. 1 have now been read). A failure of the RAck flag to be set during step (6) indicates a fault associated with that flag and/or a fault associated with an inability to successfully execute a write operation and a successive read operation.
As may now be appreciated, steps (1)-(6), comprising the first sequence of operations, serve to detect a first set of functional FIFO faults associated with the ORP, WE and RE functions, as well as faults associated with the RAck and WAck flags.
Steps (7)-(13) comprise a second sequence of operations. This second sequence is executed to detect faults associated with the Re-Transmit (RT) and Reset (RS) functions of the FIFO 100 of FIG. 1. The RS operation performs two separate functions. First, the RS operation resets both the WAR 112 and WAR so each address the first (i.e., the 0 th ) row of storage locations in the RAM 102. Also, to avoid a potential conflict when both the WAR 112 and RAR 112 were reset from the contents location other than the initial location, the RS operation must also reset an internal FIFO register (not shown), referred as the Last Operation (LO)register, to indicate that the last operation executed was a RO. If LO register was not reset to indicate a RO occurred following a reset operation, then when WAR 112 and RAR 114 were reset from same content location, it would not be possible to tell if the FIFO 100 was full or empty. Thus, to successfully reset the FIFO 100, the RS function has to initialize the Last Operation (LO) executed by the FIFO 100 to a RO. This aspect of the RS function may be tested by setting the LO to a WO and then performing a RS operation. If the LO register is not reset to indicate that the last operation was a RO, then the RS operation was faulty.
Also, the RS operation must set the WAR 112 and the RAR 114 of FIGS. 1 and 2 to the IA of 1,0 . . . . 0 regardless of the previous contents of each register. The ability of the control block 116 to reset the WAR 112 and the RAR 114 has to be tested for every address in the WAR and RAR (not necessarily for every combination) because one or more registers (ring address cells) in the WAR and RAR may have a reset input that may malfunction. Such a malfunction could cause a reset from an address such that the WAR 112 or RAR 114 might contain an address having two "1 s" rather than a single "1".
To determine if the both the WAR 112 and RAR 114 can be correctly reset, a RS operation is executed from successive addresses in the WAR and in the RAR. For ease of discussion, each successive address (i.e., each successive cell in the WAR 112 and RAR 114) from which an RS operation is commenced will be referred to as a Test Address (TA). When the RS operation is successful, both the WAR 112 and the RAR 114 should contain an address of 1, 0, 0 . . . . 0, indicating that both the RAR and WAR now address the IA (i.e., the first word in the RAM 102). Thus, the problem is to detect the presence of a "1" at the TA of the WAR 112 or the RAR 114 following the RS.
A RS fault associated with the WAR 112 or with the RAR 114 can be detected by shifting the WAR by performing a plurality of write operations. The fault (RAR) TA!)=1 (signifying a one at the test address TA) will be detected after TA successive WOs by the condition FF=1. By the same token, the fault (WAR TA!)=1 will be detected after n-TA successive WOs by FF=1. As will become better understood from an explanation of the operations performed during steps (7)-(13), the RS function is evaluated by performing TA successive ROs and WOs followed by an RS operation. If thereafter, the FF flag is set to a logic "1" or high level, then a RS fault has occurred.
The RT operation, which causes the RAR 114 to be reset to the IA, may fail for only a single read address. Assuming that the RS and RT operations are initiated by the same circuitry (not shown) with the control block 116 of FIG. 1, the RT only has to be tested for a single read address unequal to the TA, in addition to RS operation, for every read address to detect a fault in the RAR 114.
Referring to FIG. 3, testing of the RS and RT operations is commenced upon the execution of step (7), whereupon the control block 116 of FIG. 1 causes the FIFO 100 to commence a RT operation. Following the RT operation, the RAR 114 should be reset to the IA to address the first word in the RAM 102. Previously, this word had been read during step (6) so that the EF flag is now set to a logic high or "1" level, signifying that all of the words previously written in the FIFO 100 of FIG. 1 have now been read. However, once the RT operation is commenced during step (7), the RAR 114 of FIG. 1 once again addresses the first word in the FIFO 100 that is assumed to be unread. As a consequence, the EF flag is now zero as is the FF flag.
Following step (7), step (8) is executed and a RS operation is commenced to reset both the WAR 112 and RAR 114 to the IA to address the first word in the RAM 102. Upon execution of the RS operation, the Last Operation (LO) is remembered in order to determine the status of the EF and FF flags. Since LO=RO following step (6), the EF flag should be a logic "1" or high level since the last written word has been read. The FF flag remains at a logic "0" or low level because the FIFO 100 has not yet been completely written with data.
After step (8), step (9) is executed TA-1 times, whereupon a write operation (WO) is commenced upon each execution of step (9) to successively write values in the RAM 102, beginning from the address TA-1. After each execution of step (9), step (10) is executed to perform a RO to read the value at the same address that was written to during the previous WO executed during step (9). Thus, like step (9), step (10) is executed TA-1 times. Once a WO and a RO operation have been executed TA-1 times in succession, step (11) is executed and a RS operation is commenced. If, upon execution of the RS operation during step (11), the FF flag is found to be a logic "1", then an RS fault has occurred. At this time, the RAM 102 should be empty because every address to which a value had been written during step (9) should have been read during step (10).
To completely test the RS function, it is necessary to determine if a logic high level or "1" appears at the TA of the WAR 112 or RAR 114. For this reason, following step (11), step (12) is executed n-1 times whereupon a WO is commenced during each execution of step (12) to successively write values into the RAM 102, commencing from the initial location to the n-1 th location. Following the last execution of step (12), a RS operation is commenced during step (13). If, after the RS operation is executed during step (13), the FF flag is found to be a logic "1" or high level, then an RS fault has occurred. This is because the RAM 102 should not be completely full at this time.
Following step (13), steps (14)-(22), constituting a third sequence of operations, are executed. As will be discussed, the third sequence of operations tests the EF and FF flags, the type II and type IV address faults, Stuck-at Faults (SAFs), Transition Faults (TFs), state Coupling Faults (CFsts), inversion Coupling Faults (CFins) and Multi-Port Faults (MPFs). The two step of the third operation sequence are steps (14) and (15) which are is executed in sequence n times immediately after step (13). During each execution of step (14), a WO is commended to write a word of all zeros into a successive one of n locations in the RAM 102, commencing at the first location and proceeding until the n th location is written. After each execution of step (14), step (15) is executed and a RO (read operation) is initiated to read whether a word of all zeros has been read into the previous storage location of the RAM 102 of FIG. 1 that had been written with all zeros.
At the completion of the last execution of step (15), it should be appreciated that n of the storage locations in the RAM 102 have now been read. At this time, the EF flag should be at a logic "1" or high level. Thus, if the EF flag has been set to a logic "0" or low level following the last execution of step (15), then the flag was set in error. Until the last execution of step (15), the FIFO 100 should not be empty because all of the n rows of the RAM 102 have not been read. Thus, EF flag should not be set to a logic "1" level prior to this time. Thus, a check on the status of the EF flag also occurs the repeated execution of step (14) as well.
MPFs and address faults AF-II and AF-IV, as well as faults associated with the Full FIFO (FF) flag, are detected upon execution of the steps (16)-(23). Step (16) is executed after the last execution of step (15), and upon execution of step (16), a RT operation is commenced to reset the RAR 114 of FIGS. 1 and 2 to the IA (initial address). Thereafter, steps (17) and (18) are executed in sequence n times. Upon each execution of step (17), a RO is commenced to read the stored word at a successive one of n storage locations in the RAM 102, commencing at the initial (0 th ) location, while at the same time, the data input line DI is held to a logic "1" or high level. After each execution of step (17), step (18) is executed. Upon each execution of step (18), a WO (write operation) is commenced to write a word of all ones in a successive one of the storage locations in the RAM 102 previously read during step (17). After the last execution of step (18), the FF flag should now be set to a logic "1" or high level since the RAM 102 should now be full.
During each successive execution of step (17), a zero should be read at the corresponding storage location in the RAM 102 because of the previous WO executed during step (14). Thus, if a zero is not read during each execution of step (17), then a Stuck-At Fault (SAF) may have occurred. Also, after the last execution of step (17), the FIFO full flag FF should not be set since the FIFO 100 fully is not completely full because only n-1 locations were written with data. At this time the EF should also not be set since the FIFO 100 is not completely empty. However, after the last execution of step (18) there will have been n WOs so that the FF should now be at a logic "1" or high level. A type IV address fault may also manifest itself at this time
Following the last execution of step (18), steps (19) and 20 are executed n times. During each execution of step (19), the data input line DI is held to a logic low or "0" level while a RO is commenced. The RO is performed during each successive execution of step (19) to read a successive one of n of the storage locations in the RAM 102 to determine if a word of all ones is present. Since a word of all ones was previously written into each successive storage location in the RAM 102 during step (18), a word of all ones should be read upon each successive execution of step (19). If not, then a MPF or SAF may have occurred. After each execution of step (19), step (20) is executed and a WO is commenced to write a word of all zeros into each a successive one of n locations in the RAM 102 to detect type IV address faults.
During steps (17) and (19), the Data Input (DI) line is held to a logic "1" and logic "0", respectively, while at the same time a RO is commenced to read a logic "0" and a logic "1", respectively, at each successive storage location in the RAM 102. If the logic vale on the DI line is read, rather than the true value in the storage location, then a MPF associated with the multiple accessing mechanism of that location has occurred.
Steps (17)-(20), when executed, serve to detect the presence of a type IV addressing fault (AF-IV). An AF-IV associated with the WAR 112 occurs when a word is written to both of a pair of storage locations i and j in the RAM 102 when an attempt is made to write to either of the locations i and j individually. In a similar fashion, an AF-IV associated with the RAR 114 occurs when word is read at both a pair of storage locations i and j in the RAM 102 when an attempt is made to read either of the locations i and j individually. To detect this type of addressing fault, a test that contains (rx, wx)(rx, wx) or (rx/x wx)(rx/x, wx/x) is needed. It is this type of test that is performed upon execution of steps (17)-(20).
Following the last execution of step (20), step (21) is executed in succession n-1 times. During each successive execution of step (21) a RO is performed on a successive one of n-1 locations in the RAM 102 to read whether a word of all zeros had been written. If a word not containing all zeros is read during any execution of step (21), then a possible transition fault or a type II addressing fault may have occurred. Following step (21), step (22) is executed to commence a read operation to read a word of all zeros. Upon the execution of step (22), the EF flag should now be set because the all of the words stored in the RAM 102 should have been read.
Following the first execution of steps (14)-(22), the steps are executed again for each of several different data or background patterns in order to properly test for the presence of state coupling faults (CFst) that occur as the result of the bit in one storage location improperly influencing the value of the bit in an adjacent location. As discussed above, during the first execution of steps (14)-(22) a background pattern of all ones and zeros is written. Next, a background pattern of (0 0 0 0 1 1 1 1 . . . ) and its complement (1 1 1 1 0 0 0 0 . . . ) are written. Thereafter, a background pattern of (0 0 1 1 0 0 1 1 . . . ) and its compliment (1 1 0 0 1 1 0 0 . . . ) are written. This background pattern is followed by a pattern of (0 1 0 1 0 1 0 1 . . . ) and its complement of (1 0 1 0 1 0 1 0 . . . ). The number and constitution of the background patterns corresponds to the number of bits B in each row in the RAM 102. In practice, log (B)+1 separate patterns are needed to test for such state coupling faults. Thus when B equals eight, then four separate background patterns are necessary.
Steps (23)-(31 ) comprise the fourth operation sequence and are executed following step (22) to detect the following type of faults: AF-II, AF I, DRF and SOF as well as faults associated with the WAck signal and with the OWP feature of the FIFO 100. Step (23) is executed n-1 times after step (22) to initiate a WO to alternately write words of all zeros and all ones into the RAM 102. For example, upon the first execution of step (23), a word of all zeros is written at the first (0 th ) location in the RAM 102. Upon the next execution of step (23), a word of all ones is written at the second location and so on. Following step (23), step (24) is executed and a WO is initiated to write a word of all ones at the location n-1 in the RAM (102). Upon the execution of step (24), all of the n locations in the RAM 102 will have been written so that FF flag should now be set to a logic "1" or high level. If the flag has not been set, then a type I addressing fault (AF-I) has occurred.
After step (24), step (25) is executed whereupon the write clock (WCK) signal is asserted while the write enable (WE) line is also asserted. Under this condition, the OWP feature of the FIFO should be effective to prevent a write operation from occurring since the FF flag is now at a logic "1" or high level. If the WAck flag goes to a logic "1" or high level at this time, then a fault exits with either the OWP feature of the FIFO 100 and/or the WAck flag.
Following step (25), step (26) is executed, whereupon a delay state is entered so that no operation is executed. The purpose in entering a delay state during step (25) is to allow any potential data retention to manifest itself when data is subsequently read from and written to the RAM 102. Following step (26), then steps (27) and (28) are executed in sequence n times to read and write n successive storage locations in the RAM 102. During step (27) each successive location is read to determine if alternate storage locations contain all zeros and all ones. For example, during the first execution of step (27), the currently addressed storage location in the RAM 102 is read to determine if it contains all zeros. During the next successive execution of step (27), the next successive storage location in the RAM 102 is read to determine if a word of all ones is present and so on. The purpose in alternating writing words of ones and zeros into the RAM 102 is to determine whether the particular value written into a storage location has leaked so that upon a subsequent reading of that location, the previously written value is no longer present.
After each execution of step (27), step (28) is executed to alternately write words of all ones and all zeros into the RAM 102. Thus, after the first execution of step (28), a word of all ones is written into the currently addressed location in the RAM 102. Upon the next successive execution of step (28), a pattern of all zeros is written in the next successively addressed storage location and so on.
The read operation commenced each time step (27) is executed serves to detect the word written previously during each successive execution of step (23). A Stuck-Open Fault (SOF), occurring as a result of the inability of a storage location in the RAM 102 to reflect the value previously written therein, will manifest itself during the execution of step (27). Likewise, a data retention fault (DRF), occurring as a result of a leakage in one or more of the bits in a previously written word over time, may also manifest itself at this time.
Following step (28), another delay occurs during step (29). Thereafter, step (30) is executed successively n-1 times to read the RAM 102 to determine if each of n-1 successive locations in the RAM had been alternately written with words of all ones and all zeros as should be the case following the last successive execution of step (28). As during step (27), DRFs and SOFs will manifest themselves during step (30). Following step (30), a RO is executed during step (31) to determine if the currently addressed location in the RAM 102 contains a word of all zeros. When executed in this manner, steps (27), (30) and (31) will manifest all possible SOFs and DRFs.
As should be appreciated from the foregoing description, the steps (1)-(31), when executed in the manner described, serve to manifest the possible memory, address and functional faults of the FIFO 100. The method of testing, represented by steps (1)-(31 ) does not require any modifications to the design of the FIFO 100. However, there are aspects of the method of FIG. 2 which may be viewed as disadvantageous. For example, the steps (7)-(13) performed for detecting faults associated with the RS operation have a complexity (O) on the order of O(n 2 ). Further, the steps (14)-(22) that are performed to detect state coupling faults (CFst) have a complexity of O(n logB). Further, the method of FIG. 3 is provides somewhat limited coverage of indepotent coupling faults CFid.
If it is possible to alter the design of the FIFO 100, then a more streamlined test method can be provided. Referring to FIG. 4, there is shown alternate embodiment of a FIFO 100' especially designed for testability in accordance with the invention. The FIFO' 100 of FIG. 4 shares many elements in common with the FIFO 100 of FIG. 1 and therefore, like elements have been designated by like reference numbers. Thus, as compared to the FIFO 100 of FIG. 1, the FIFO 100' of FIG. 4 also includes a RAM 102, data input and output registers 108 and 110, respectively, Write Address and Read Address Registers (WAR) and (RAR) 112 and 114, respectively, as well as a FIFO control block 116, all functioning in the same manner as described previously.
To facilitate its testability, the FIFO 100' of FIG. 4 includes a Test Pattern Generator (TPG) 118 for generate test patterns, in the form of vectors, for input to the RAM 102. The test patterns from the TPG 118 are multiplexed by a multiplexer 120 with signals appearing on the data input line DI. During testing intervals, the multiplexer 120 passes test patterns from the TPG 118 to the data input register 108 for input to the RAM 102. During non-testing intervals, the multiplexer passes signals received on the DI line to the RAM 102.
To further facilitate testing, the FIFO 100' of FIG. 4 also includes an Output Data Evaluator (ODE) 120 coupled to the output of the Output Data Register 110 so as to receive the same data that is output to the Data Output line DO. In practice, the ODE 120 takes the form an AND and OR tree (not shown) for ANDing and ORing the data on the DO line to compact the output data from the Data Output Register 110 during test intervals. The output data compacted by the ODE 120 during test intervals takes the form of responses generated by the RAM 102 to the test patterns provided by the TPG 118.
Overall control of the TPG 118 and the ODE 120, as well as control of the FIFO control block 116 is provided by way of a Built-In Self-Test (BIST) control 122 that typically comprises a finite state machine (not shown). The control signals from the BIST control 122 are multiplexed by a multiplexer 124 with the signals WE, RE, RS and RT externally supplied to the FIFO block 1116 as described previously, and as a pair of control signals Write Pointer Inhibit (WPI) and Read Pointer Inhibit (RPI). The WPI and RPI control signals operate to inhibit the WAR 112 and RAR 114, respectively, from being imcremented after a WO and RO, respectively. The pointer inhibit function associated with each the WAR 112 and RAR 114 is provided for purposes of testability.
In addition to supplying control signals to control testing, the BIST control 122 is also responsive to the EF, FF, RAck and WAck flags generated by the FIFO control 116. In accordance with the EF, FF, RAck and WAck flags, the BIST control 122 operates to generate a pair of signals BIST Flag (BF) and BIST Complete (BC). The BF and BC flags may be accessed by an external test device (not shown) such as a personal computer, to determine the operating status of the FIFO 100'.
Referring to FIG. 5, there is shown in tabular form the steps of a method, in accordance with a second aspect of the invention, for testing the FIFO 100' of FIG. 1. Step (1') is the first step of the method illustrated in FIG. 5 and is executed to initiate an RS operation, thereby resetting both the WAR 112 and RAR 114 of FIG. 4. At this, FF=0 while EF=1 since the RAM 102 is empty. Step (2') is executed following step (1'), whereupon the Read Clock signal (RCK) is asserted at the same time the Read Enable (RE) signal is asserted at a logic "1" or high level to initiate a RO. If the FIFO 100' of FIG. 4 is operating properly, the Over Read Protection (ORP) feature of the FIFO should inhibit the RO since EF=1 at this time. Thus, the presence of a logic "1" or high level RAck flag at this time signifies that either this flag was improperly set, or that the ORP feature of the FIFO 100' is defective.
Step (3') is executed following step (2'), whereupon the Write Clock (WCK) is asserted at the same time the Write Enable (WE) signal is asserted at a logic "1" or high level. Since FF=0, a WO may occur. However, since no actual WO has taken place, the WAck should not be asserted. After step (3'), step (4') is executed and a WO is initiated to write a word of all zeros at the first location of the RAM 102 of FIG. 4. At this time, the WAck flag should be set. If not, then a fault has occurred.
Following step (4'), step (5) is executed, whereupon the RCK signal is asserted at the same time the RE signal is asserted at a logic "1" or high level to initiate a RO. Since a WO had occurred previously during step (4'), the EF flag should no longer be set. Thus, a RO may occur. However, since an actual RO has yet to occur, the RAck flag should not yet be set. Step (6') is executed after step (5') to initiate a RO to read if a word of all zeros is present at the currently addressed location of the RAM 102. Since a word of all zeros was previously written at that location during step (4'), such a word should be read during step (6'). The ability to correctly read a word of all zeros during step (6') verifies the ability to execute a WO followed by a RO. Also at this time, the flag RAck should also be set since a RO occurred during step (6'). Steps (1')-(6') correspond to steps (1)-(6) of FIG. 2 are executed to detect the same type of faults.
Step (7') follows step (6'). During step (7'), a RT operation is initiated to reset the RAR 114 of FIG. 4 in the same manner as step (7) of FIG. 2. Next, step (8') is executed, whereupon a Serial Loading Operation is initiated to load a value of zero in the initial address (IA) position in both the WAR 112 and the RAR 114 and ones in the other positions. During execution of the SLO, the n-bit circular loop associated with each of the WAR 112 and RAR 114 is broken, allowing each register to be scanned by n operations. In this way, the reset function of the FIFO 100' of FIG. 4 can be tested by initiating a single RS operation during step (9'), thereby reducing the complexity of the operation associated with detecting faults associated with the RS operation. If the RS operation has been successfully performed during step (9'), then the EF flag, which was unset during step (7'), should now be set. The failure of the EF flag to be set at this time signals a fault associated with the RS operation.
Following step (9'), a modified "march" algorithm is executed to test for faults associated with the EF and FF flags as well as various memory and addressing faults. The modified march algorithm is initiated upon execution of step (10'), whereupon a WO is executed n times to write a word of all zeros in each successive location in the RAM 102. Having now written the RAM 102 with data, the EF flag should not be set to a logic "1" or high level. After each execution of step (10'), step (11') is executed and a RO is initiated to successively read each of the n locations previously written with all zeros. (Thus steps (10') and (11') are both executed n times.) If the RO performed during each execution of step (11') was successful, then the EF flag should be asserted after the last execution of step (11') because all of the locations in the RAM 102 that were previously written have now been read, rendering the RAM empty (i.e., completely read).
After the last execution of step (11'), step (12') is executed and a RT operation is performed to reset the RAR 114. Next, step (13') is executed n times to perform a sequence of read and write operations. During each execution of step (13'), the DI line is held to a logic "1" or high level while a RO is initiated to read if a word of all zeros is present at a successive one of n-1 storage locations in the RAM 102. After the RO, a pair of Write Inhibit (wi) operations are commenced in succession to write a B bit word into the RAM 102 without incrementing the WAR 112. During the first wi, a word of all ones is written, whereupon a word of all zeros is written during the second wi. After the second wi, a WO is commenced word of all ones is written in the RAM 102. Thus, during each successive execution of step (13'), an RO and three WOs are executed in succession. Stuck-at faults (SAFs), Multiport Faults (MPFs), Linking Faults (LFs) as well as Read Inhibit (RI), and Write Inhibit (WI) faults will manifest themselves during step (13').
Following step (13'), step (14') is executed n times. During each execution of step (14'), a Read Inhibit (ri) operation, a wi operation, an RO and a WO are performed in sequence. During the ri, a B-bit word is read from the RAM 102 at the currently addressed location, without incrementing the RAR 114 of FIG. 4, to determine if the word is all ones. During the wi executed next, a word of all zeros is written into the currently-addressed location in the RAM 102 without incrementing the WAR 112 of FIG. 4. During the RO executed after the wi, the currently addressed location in the RAM 102 is read to establish whether a word of all zeros is present. However, unlike the previous ri operation, during the RO, the RAR 114 of FIG. 4 is incremented. Following the RO, a WO is initiated to write a word of all ones. When this WO is executed, the WAR 112 of FIG. 4 is incremented. Upon the last execution of step (14'), type IV address faults, Transition Faults (TFs), and faults associated with the wi and ri operations and with the FF will manifest themselves.
After step (14'), step (15') is executed n times. During each execution of step (15'), the DI line is held to a logic "0" or low level while a first Write Inhibit (wi) operation is commenced to write a word of all zeros into the RAM 102 without incrementing the WAR 112 of FIG. 4. Following the first wi, a second wi is commenced to write a word of all ones, again without incrementing the WAR 112 of FIG. 4. After the second wi, a WO is commenced to write a word of all ones is written in the RAM 102. After upon the execution of the WO, the WAR 114 of FIG. 4 is incremented Thus, during each successive execution of step (15'), two wi operations are executed in succession followed by a WO. At the end of the last execution of step (15'), Stuck-at faults (SAFs), Multiport Faults (MPFs), Linking Faults (LFs) as well as type I addressing faults will manifest themselves.
The WAR 112 and the RAR 114 are inhibited from being incremented in the manner described above to permit that complete detection of indepotent coupling faults (CFids) that require that the FIFO 100 execute at least three separate read and write operations, such as r 0 w 1 w 0 , at each storage location, or two operations with reverse address direction, such as .arrow-down dbl. r 1 w 0 R 0 . A conventional FIFO, such as the FIFO 100 of FIG. 1, is incapable of executing three or more read and write operations at the same storage location and is also incapable of performing inverse addressing operations. However, by inhibiting the WAR 112 and the RAR 114 by inhibit operation described above, then three or more read and write operations can be executed at the same address, thus permitting complete detection of CFids. Further, the above-described inhibit operation can be employed to manifest Linking Faults (LFs) which require four read and write operations at each address.
Following the last execution of step (15'), step (16') is executed n times. During each execution of step (16') a ri operation, a wi operation, a RO and a WO are performed in sequence. During the ri, a word is read from the RAM 102 at the currently addressed location, without incrementing the RAR 114 of FIG. 4, to determine if the word is all zeros. During the wi executed next, a word of all ones is written into the currently-addressed location in the RAM 102 without incrementing the WAR 112 of FIG. 4. During the RO executed after the ri, the currently addressed location in the RAM 102 is read to establish whether a word of all ones is present. However, unlike the ri operation, during each RO, the RAR 114 of FIG. 4 is incremented. Following the RO, a WO is initiated to write a word of all zeros. When this WO is executed, the WAR 112 of FIG. 4 is incremented. Upon the last execution of step (16'), type I and IV address faults, TFs will manifest themselves as well as faults associated with the FF.
After the last execution of step (16'), step (17') is executed B times during which a wi is executed to write a walking zeros pattern without incrementing the WAR 112 of FIG. 4. After each wi, a ri is executed to read whether a walking zeros pattern was indeed written. After the last execution of step (17'), step (18') is executed B times during which a wi and a ri are executed in succession to write a walking ones pattern and then to read the walking ones pattern just written, respectively. Steps (17') and (18)' collectively serve to manifest Programmable Space Compaction Faults (PSCFs) associated with the compaction provided by the ODE 120 of FIG. 4.
After the last execution of step (18'), step (19') is executed and the WCK signal is asserted while maintaining the WE signal at a logic "1" or high level to attempt a WO. However, at this time, the FF should be at a logic high or "1", thus precluding a WO if the OWP feature of the FIFO 100 is operational. Thus, by monitoring the status of the WAck flag during step (19'), a fault with this flag, and/or with the OWP feature of the FIFO 100, can be detected.
Step (20') is executed next, whereupon a delay occurs. Following step (20'), step (21') is executed n times. During each execution of step (20'), a RO is performed to read whether a word of all zeros is present at each successive location in the RAM 102 of FIG. 4. At the end of step (21'), type II address faults will manifest themselves. Following step (21'), step (22') is executed n-1 times to write a word of all ones. Step (21 ') serve to manifest DRFs by detecting for retention of words of all zeros.
Step (23') is executed after step (22'). During step (23'), a WO is executed to write a word of all ones in the currently addressed location in the RAM 102. Thereafter, step (24') is executed, whereupon another delay occurs in order to detect for data retention faults occurring because of complementary values (all ones). Finally, step (25') is executed n times. During each execution of step (25'), a RO is performed to read whether a word of all ones is present at each successively addressed location in the RAM 102 of FIG. 4. DRFs that have not previously manifested themselves will do so during step 25' because at this time, an examination is made whether words of all ones have been retained.
The foregoing describes a method for testing a dual-port, RAM-Type ring-address FIFO 100 to test for memory, address and functional faults.
It is to be understood that the above-described embodiments are merely illustrative of the principles of the invention. Various modifications and changes may be made thereto by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof. | A dual-port, RAM-type ring-address FIFO (100) is tested by causing the FIFO to execute a composite test method comprised of set of interwoven steps (( 1 )-(31 ) or (1')-(25')). Upon execution, the steps of the composite method cause the FIFO (100) to manifest all possible memory, address and functional faults. The test method manifests faults by causing the FIFO (100) to alter the state of the various flags it normally sets and by altering the logic state of the data normally produced by the FIFO. | 6 |
BACKGROUND OF THE INVENTION
[0001] (1) Field of the Invention
[0002] The invention relates to a shoe, and more particularly to an integral shoe with the roller function.
[0003] (2) Description of the Prior Art
[0004] A shoe is manufactured by adhering a sole and an upper, which are individually manufactured, together with an adhesive agent, or by sewing the sole and the upper at the corresponding contact surfaces so that the sole and the upper are combined together to form the shoe. A skate shoe is also manufactured in the same manner except that a roller assembly has to be mounted on the sole of the skate shoe.
[0005] However, this manufacturing method adopts the adhesive agent, which has the material aging problem, so that the upper and the sole tend to be separated. In addition, the used adhesive agent causes the air pollution, which becomes a great loading on the environment protection issue. Also, the workers who work in the workshop where the adhesive agent is placed always breathe the odor of the adhesive agent so that the health of the workers tends to be influenced. Thus, it is an important subject to improve these problems in the shoe manufacturing industry.
SUMMARY OF THE INVENTION
[0006] In view of the above-mentioned problems, it is therefore an object of the invention to provide an integral shoe with a roller assembly, wherein the shoe is integrally formed, and the roller assembly is mounted on a sole of the shoe to possess the function of the skate shoe and to avoid the consideration induced by adhering an upper and the sole together.
[0007] To achieve the above-identified object, the invention provides an integral shoe having an upper and a sole, which is characterized in that: the upper and the sole are integrally formed, the sole is formed with one concave cavity or a plurality of concave cavities, in which one roller assembly or roller assemblies are mounted, wherein the roller assembly has a rotatable roller.
[0008] Therefore, the invention has the following advantages according to the technological means of the invention.
[0009] First, the upper and the sole of the shoe are integrally formed so that the cost of the adhesive agent can be saved and the environmental pollution caused by the adhesive agent can be avoided. In addition, the upper and the sole cannot be easily separated from each other.
[0010] Second, the integral shoe of the invention has the novel structure and function. Because the shoe is integrally formed, the sole is formed with the cavity so that the roller assembly can be mounted therein. There are many types of the roller assemblies, or even the roller base of the roller assembly can be inserted into the cavity so that the exterior is beautiful and the roller assembly can be replaced in a novel and fun manner.
[0011] Further aspects, objects, and desirable features of the invention will be better understood from the detailed description and drawings that follow in which various embodiments of the disclosed invention are illustrated by way of examples.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a pictorially exploded view showing an integral shoe according to a first embodiment of the invention.
[0013] FIG. 2 is a cross-sectional view showing the integral shoe according to the first embodiment of the invention.
[0014] FIG. 3 is a pictorially exploded view showing an integral shoe according to a second embodiment of the invention.
[0015] FIG. 4 is a cross-sectional view showing an integral shoe according to a third embodiment of the invention.
[0016] FIG. 5 is a pictorially exploded view showing an integral shoe according to a fourth embodiment of the invention.
[0017] FIG. 6 is a cross-sectional view showing the assembled integral shoe according to the fourth embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The invention provides an integral shoe with a roller assembly. In the preferred embodiment as shown in FIG. 1 , a shoe 10 includes an upper 11 , a sole 12 and a roller assembly 20 , which is additionally combined.
[0019] As shown in FIGS. 1 and 2 , the upper 11 and the sole 12 of the shoe 10 are integrally formed, and no seam is formed between the upper 11 and the sole 12 . Concave non-circular cavities 13 are respectively formed on the sole 12 at positions close to the toe and the heel. A slot 131 for communicating the cavities 13 together is also formed on the sole 12 . The slot 131 and the cavities 13 have openings facing in a direction toward the bottom side of the sole 12 .
[0020] The roller assembly 20 is correspondingly mounted in the cavities 13 and the slot 131 . The roller assembly 20 includes two roller bases 21 and a link 22 connecting the roller bases 21 together. The roller base 21 is formed with an inner slot 211 having an opening facing the opening of the cavity 13 . The outer profile of the roller base 21 corresponds to the cross-sectional area of the cavity 13 and the roller base 21 is slightly tightly pressed against the cavity 13 so that the roller bases 21 and the link 22 are arranged in the cavities 13 and the slot 131 . The sole 12 is made of a plastic material and has the elasticity. So, the roller base 21 and the link 22 cannot easily fall out after they are mounted into the cavity and the slot. One roller 23 is mounted in each of the roller bases 21 , and bearings are mounted at the center portion of the roller 23 so that a shaft 231 may be mounted in the bearings. Thus, when the roller 23 is mounted in the inner slot 211 , two ends of the shaft 231 are fixed to the inner sidewalls of the inner slot 211 so that the roller 23 may be rotated relatively to the shaft 231 . The radial surface of the roller 23 faces the side surface of the shoe 10 .
[0021] Consequently, the roller assembly 20 is formed after the roller 23 is mounted on the roller base 21 , and can be fully inserted into the cavities 13 and the slot 131 , as shown in FIG. 2 . One portion of the roller 23 protrudes from the sole 12 . Consequently, a user may wear the shoe 10 and then apply a force to the roller assembly 20 to make the roller 23 roll on the ground so that the shoe may serve as a skate shoe.
[0022] Consequently, the shoe 10 of the invention has the upper 11 and the sole 12 , which are integrally formed. So, the upper 11 and the sole 12 need not to be adhered together by the adhesive agent so that the problem of the poor adhesive intensity of the adhesive agent and the problem of the environment protection can be avoided. That is, the shoe of the invention may be easily manufactured and satisfy the environment protection effect.
[0023] In addition, the sole 12 has the cavities 13 and the slot 131 corresponding to the roller assembly 20 and the two rollers 23 thereof. Thus, the roller assembly 20 can be fully and directly inserted into the cavities 13 and the slot 131 in a simple and quick manner without any screwing element, which deteriorates the exterior of the shoe. In addition, different types or colors of roller assemblies 20 may be used according to the user's requirements so that the variations in the visual feeling and the novel feeling of the shoe can be added. Because the roller assembly 20 has the roller bases 21 and the link 22 , which are tightly pressed against the cavities 13 and the slot 131 , the roller assembly 20 can be forced out easily.
[0024] As shown in FIG. 3 , only one single cavity 13 is formed on a sole 12 of a shoe 101 at the heel position. Thus, a roller assembly 201 only includes one roller base 21 and one roller 23 , and the skate shoe with one single roller may be formed after the roller assembly 201 is inserted into the cavity 13 .
[0025] As shown in FIG. 4 , a currently popular crocs shoe 102 may also have two roller assemblies 201 of FIG. 3 each having only one single roller. The roller assemblies 201 are mounted in the heel and toe regions. So, there are many types of the shoes suitable for the invention.
[0026] As shown in FIGS. 5 and 6 , a roller assembly 202 may be modified in many ways. That is, one cavity or two cavities 14 may be formed on a sole 12 of a shoe 103 , and notched slots 141 are formed on the opposite inner sidewalls of each cavity 14 . The roller assembly 202 has a shaft 241 , which is movably mounted to and penetrates through the center of a roller 24 . Thus, after the roller assembly 202 is mounted in the cavity 14 , two ends of the shaft 241 exposed out of the roller 24 are inserted into the notched slots 141 so that the roller 24 is partially accommodated in the cavity 14 and partially exposed out of the sole 12 and the simpler skate shoe can be formed.
[0027] New characteristics and advantages of the invention covered by this document have been set forth in the foregoing description. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention. Changes in methods, shapes, structures or devices may be made in details without exceeding the scope of the invention by those who are skilled in the art. The scope of the invention is, of course, defined in the language in which the appended claims are expressed. | An integral shoe with a roller assembly. The integral shoe has an upper and a sole, which are integrally formed. At least one cavity is formed on the sole so that the roller assembly can be mounted in the cavity. Thus, the shoe with the roller function is integrally formed more quickly, and the roller assembly may also be replaced so that multiple functions can be achieved. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a spring balancer used for a lid having a heavy weight which opens or closes upward and downward around a revolution or pivot axis (hereafter merely called "lid").
As an example of such a lid having a heavy body as described above, there exists an office machine, for instance, a copy apparatus having a heavy lid.
Heretofore, the lid which is opened and closed at the time of inspection and maintenance of the copy apparatus is heavy. Accordingly, a hinge is used with a torsion spring or the like employed with the revolution or pivot axis. In this case, however, a wide space is required near the revolution or pivot axis for attaching the spring. Further, it is difficult to design the spring to agree with the moment of revolution of the lid and it is also difficult to stop it at any position through the whole process of opening and closing.
Furthermore, when such hinge as described above is not in use, the hinge is provided with a balancer, such as gas spring, oil spring or the like between the lid and the main body at a position spaced from the revolution axis. Although it is easy to make the properties of these balancers agree with the moment of revolution of the lid, these necessitate sealing techniques for the prevention of the leakage of gas or oil, whereby this causes a high cost, together with being incapable of maintaining a complete sealing for a long period. Accordingly, gas or oil leakage occurs, by all means, and the reliability as a balancer is low.
Furthermore, since the properties of said gas spring, oil spring and the like vary according to the change of the temperature, these have such defect as the difficulty of maintaining the balancer performance always constant, despite change of the environment.
SUMMARY OF THE INVENTION
The object of this invention is to provide a spring balancer wherein the overall properties of the compression spring and the friction of a friction ring used with the compression coil spring are designed to fit the moment of revolution of the lid. As a result, the lid can be operated with a small force and its movement can be stopped at any position through the whole opening or closing process.
Another object of this invention is to provide a spring balancer wherein overall properties of the balancer include spring properties of a compression coil spring and the friction between a friction ring and a rod. These properties are designed to be slightly larger than the moment of revolution of the opening and closing points near the terminal points of the lid movement and to agree with the moment of revolution of the lid at other intermediate opening and closing positions whereby when the locking of the lid at the terminal point of the closing is released, the lid is stopped in a slightly open state, thereby being capable of preventing the impact opening operation to the terminal point.
Further, another object of this invention is to provide a spring balancer in which it is possible to prevent the buckling accompanied by compressive operation of the compression coil spring through the whole opening and closing process of the lid and to use the spring properties of the compression coil spring effectively without intervention or contact with other parts by buckling of the spring and through the whole opening and closing process.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the attached drawings, the features and the effects of this invention will be described as follows.
FIG. 1 is a vertical sectional view of a spring balancer which shows the relationship of the components in a free state according to one example of this invention.
FIG. 2 is a vertical sectional view of another example of a spring balancer which shows the relationship of the components.
FIGS. 3(a), (b) are conceptual explanation views of the spring balancer in a state of employment in this invention, and
FIG. 4 is a graph which shows the relation between opening angle and torque in each spring balancer, and the lid in accordance with this spring.
DETAILED DESCRIPTION OF THE INVENTION
In a spring balancer 1 of this invention shown in FIG. 1, there is fixed a bracket 2 pivotably carried on a fixed body side (or a lid side) at one end portion of a rod 4. At one end portion of a cylinder 5, which moves slidably along the rod 4, there is fixed a bracket 3 pivotably carried on the lid side (or fixed body side).
The numerals 2a and 3a are holes whereby the spring balancer is pivotably carried on the fixed body (or the lid) and the numeral 6 is a nut.
The inserting condition of the rod 4 into the cylinder 5 in free state is such that a part of the end portion of the rod 4 is inserted into the cylinder 5, as shown in FIG. 1, said rod 4 and cylinder 5 being adapted to have a relatively adjustable inserting length, within a range of A. The range A is properly determined in accordance with the range of the opening and closing of the opening and closing material.
Inside the cylinder 5, a guide cylinder 8 is fixed to the bracket 3 at one end thereof. The relative elongation or shrinkage between rod 4 and cylinder 5 is opposed by friction between the slider 7 fixed to the inserting portion of the rod 4 and inner wall of the guide cylinder 8.
The slider 7 serves to prevent the drawing out of the rod 4 from the cylinder 5.
At the end portion of the guide cylinder 8 positioned at the inside of the open end of the cylinder 5 which is an opening of the insert, there is fixed a friction ring 9 that closely contacts with the outer circumference of the rod 4, said friction ring 9 providing a given friction when the rod 4 and the cylinder 5 relatively translate in the axial direction.
The compression coil spring 10 is attached to the brackets 2 and 3, with the rod 4 and the cylinder 5 inserted therein. The compression coil spring has a coil portion having a small diameter 10a wherein one end portion of the rod 4 is inserted therethrough, said portion being formed to have an inner diameter equivalent to the outer diameter of the rod 4; and another coil portion having a large diameter 10b which has an inner diameter equivalent to the outer diameter of the cylinder 5. Since the compression coil spring 10 has the small coil portion 10a and the large coil portion 10b, the buckling phenomenon of the coil spring at the time of compression can be effectively prevented.
The spring balancer 100 of this invention, as shown in FIG. 2, is fixed to the end of the rod together with the compression coil spring 11, and is different from said spring balancer 1 in only one point. In the spring balancer 100, there exists a guide cylinder 12 which includes therein a coil portion having the inserted rod 4 of the compression coil spring therethrough and an open end of the cylinder 5 therein.
Therefore, the same elements as those which constitute the spring balancer 1 are shown with the same numerals and the explanation is abridged.
The compression coil spring 11 is one coil spring wherein the whole length of the spring is formed to have an inner diameter corresponding to the outer diameter of the cylinder 5.
The guide cylinder 12 is designed to be approximate to the outer diameter of said coil spring in considering that the compression coil spring 11 enlarges the inner diameter of the guide cylinder slightly at the time of the compression operating. The bottom portion of guide cylinder 12 is fixed to one end of the rod 4 with nut 6 so as to grasp a sheet member 13 and a bracket 2.
Further, the whole length of the guide cylinder 12 is required to be at least a length equivalent to the length of the coil portion inserted therein, said coil portion having the rod 4 inserted therein.
Since the compression coil spring 11 has the cylinder 5 and the guide cylinder 12, the buckling phenomenon at the time of the compressive operation can be prevented effectively.
Thus, since the spring balancer 100 does not have the coil portion having small diameter 10a of the compression coil spring 10, it is possible to enlarge the range B wherein the rod 4 and the cylinder 5 relatively translate in the axial direction more than the range A in the spring balancer 1.
Then, the states of the employment of these spring balancers, 1 and 100, will be conceptually described based upon FIGS. 3(a) and (b).
The symbols C and D in FIGS. 3(a) and (b) are a fixed body and a lid respectively, and lid D is adapted to open or close around the rotational axis E.
Further, X and Z show terminal points of movement of the lid D.
The symbol S is a spring balancer, wherein the spring balancer according to this invention (1 or 100) is used. The spring balancer S is secured to fulcrums F and G rotatively through brackets (brackets 2 and 3 in an apparatus 1 or 100) at a given position spaced from the rotative axis E in fixed body C and lid D. The spring balancer S is secured so as to define the terminal point of the opening movement of the lid D. In this case, when the fulcrums F and G are designed to be positioned approximately on a perpendicular line with respect to a divided line (Y-axis) or line of contact of the fixed body C and the lid D, it is called "vertical type", while when the fulcrum F of the lid D is designed to be slightly shifted in a direction towards or away from the rotative axis E, with respect to the fulcrum G of the fixed body C, it is called "oblique type". There appears the following difference in operation concerning the balancer S according to the relation of the erected positions of the fulcrums, F and G.
In other words, the balancer S of the vertical type is smaller in extension and shortening of the length than that of the oblique type and larger in load difference.
Accordingly, in the compression coil spring 10 or 11 used for the balancer S, it is necessary to design the spring constant larger in the case of the vertical type than in the case of the oblique type. Further, in the case of the oblique type, it is desirable to use the spring balancer 100 wherein the range of the extension and the shortening of the length of the balancer S can be made larger. Furthermore, the features of the spring balancer in this invention are described based upon the graph which shows the relation between the rotation angle and the torque of the lid D represented in FIG. 4. FIG. 4 is a graph which shows the relation between the opening angle of the lid D and the torque. The curve H represents a characteristic curve in a case when there is no use of a friction ring of the type used in the balancer of this invention; in other words a characteristic curve of the compression coil spring; J is a characteristic curve of the properties of the moment of revolution of the lid D; and K is a characteristic curve of the properties of the balancer S of this invention.
As is easily understood from curve H in FIG. 4, it is impossible to make the characteristic curve of the compression ring agree with the moment of revolution J of the lid D by only using the compression coil spring, however the spring constant may be designed.
This invention is made to obtain properties which agree with the moment of revolution J of the lid D by the overall properties of the spring properties and the friction ring.
Further, with the spring balancer S according to this invention, a characteristic curve can be obtained that has properties which agree with the moment of revolution J of the lid D, during a portion of the lid movement, and also slightly exceed the moment of the revolution of the lid D near the terminal point of closing of the lid D, as shown with curve K in FIG. 4.
When the spring balancer S is designed to have a characteristic curve that agrees with the moment of the revolution J of the lid D, said lid D can be operated not only with a small force, but also can be stopped at any position through the whole process of the opening and closing of the lid D.
Further, in case that the spring balancer is designed to provide the properties represented by curve K shown in FIG. 4, when the locking of the lid D at the terminal point of the closing is released, said lid D is slightly opened to stop at point Y in FIG. 4 and an impact operation during movement of the terminal point of closing can be prevented.
Furthermore, in the spring balancer S, since a coil portion having a small diameter is formed as a part of the compression coil spring, or a guide-cylinder is used wherein the coil is inserted for preventing the buckling phenomenon of the compression coil spring, the spring properties of the coil spring can be always maintained at normal state, without contacting other parts due to the coil buckling. | A spring balancer having a compression coil spring and a friction ring. Properties of the spring and a friction force provided by the ring are designed to fit the moment of revolution of a lid that can be opened or closed upward and downward around a revolution or pivot axis. The balancer makes it possible to open or close the lid with a small force and allows stopping of the lid at any position in the whole process of the opening or the closing. | 4 |
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