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CROSS REFERENCE TO RELATED APPLICATION
This application contains subject matter related to U.S. patent application Ser. No. 07/442,789, entitled SURGICAL IMPLANT HAVING A SEMICONDUCTIVE SURFACE (inventors: Armin Bolz and Max Schaldach), filed Nov. 29, 1989, which is a counterpart of Federal Republic of Germany Application No. G 88 15 083.6 filed Nov. 29, 1988.
This application claims the priority of Federal Republic of Germany Application No. G 88 15 082.8 filed Nov. 29, 1988, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a cardiac valve prosthesis composed of a rotatably mounted, disc-shaped valve flap and an annular body. The flap includes two outwardly oriented spherical cap-shaped convex attachments which face one another at the points of intersection of a secant of the valve flap with an edge thereof. The annular body includes an interior wall having recesses conforming to the convex attachments and for providing a seat for the valve flap.
Artificial cardiac valves of the above type involve the problem of maintaining the annular body supporting the valve flap as undeformed as possible during insertion of the valve flap so that it will not be permanently deformed and its surface coatings will not be damaged.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved cardiac valve prosthesis of the above-mentioned type which makes it possible to install the valve flap without deforming the annular body.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the cardiac valve prosthesis has a rotatably mounted, disc-shaped valve flap which includes two outwardly oriented convex attachments at points of intersection of a secant of the valve flap with an edge thereof and an annular body including an interior wall having first recesses for receiving the convex attachments and for providing a bearing for the valve flap which is thus rotatable about an axis coinciding with the secant. The interior wall has second recesses communicating with the first recesses and forming a passage for the convex attachments during insertion of the valve flap into the first recesses when the valve flap is in an orientation which is beyond a fully open or a fully closed position thereof. The second recesses extend toward an exterior edge of the annular body.
The invention is based on the earlier recognition that if the annular body is provided with a groove in such a manner that the valve flap can be inserted into its seat exclusively in a position which it cannot assume hydrodynamically in the implanted state, then a deformation of the outer annular body is prevented and further, it is ensured that the valve flap cannot become disconnected from the bearing (bearing socket) in the operating state. Advantageously, by providing the interior wall of the annular body of the cardiac valve prosthesis with the above-defined second recesses which form a passage for the convex attachments to the upper and/or lower edge of the ring in such a position of the valve flap which is beyond a position which the flap is able to assume hydrodynamically, the safety of the patient is ensured without making installation more expensive.
According to a further feature of the invention, the convex attachments are able to pass through the passage when the valve flap is in an angular position which, based on an operating position, is disposed beyond the open or closed position defined by a first and second stop, respectively. In this way it is ensured that the angular position for insertion is not attained again in the implanted state. The first stop for the valve flap in its open position is preferably disposed behind the valve flap support when seen in the direction of flow and the second stop for the closed position of the valve flap is formed by an edge provided at the interior wall of the annular body. Both stops preferably have a barb-shaped cross section.
According to a further feature of the invention, the annular body is provided with a ledge disposed tangentially along the interior wall in a region between the two seats (valve supports) so as to limit flap movement in the direction beyond the closed position.
According to yet another advantageous feature of the invention, a semiconductive material is used as the coating for the implant for preventing the flow of electron currents which would enhance fibrin activation. To accomplish this, the surface layer may be extremely thin. The appropriate coatings can be produced cost-effectively by PVD (plasma vapor deposition) or CVD (chemical vapor deposition) methods. In this connection, the production of amorphous SiC according to the plasma assisted CVD method is particularly favorable. In this way, layers of a very low electrical state density can be produced.
The semiconductive coating is composed either of an amorphous or a microcrystalline material. The peak-to-valley height (roughness) of the surface is less than 0.1 μm. In this way, the agglomeration and destruction of corpuscular components of the blood and the activation of the coagulation system connected therewith are prevented. The solution is based on the concept that at the energy level of the electronic protein states in blood the state density of the coating is low. Thus, thrombogenic charge exchanges between coagulation-specific proteins and the implant surface are prevented.
Preferably, amorphous silicon carbide (a-SiC:H), a precipitation product of a mixture including silane (SiH 4 ) and/or methane (CH 4 ) is employed for the antithrombogenic coating. Silicon oxide (a-SiO:H) can advantageously be used as well.
In particular, the coating is made as free of pores as possible. This also increases its stability. Instead of silicon carbide, silicon nitride (a-SiN:H) can also be employed which, in this respect, has the same surface characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the annular body of the cardiac valve prosthesis according to a preferred embodiment of the invention.
FIG. 2 is a sectional view along the line II--II of FIG. 1.
FIGS. 3a and 3b are sectional views along the line III--III of FIG. 1, showing the valve body in two different positions.
FIG. 4 is a magnified sectional view of a surface portion of the embodiment of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Of the preferred embodiment of the cardiac valve prosthesis according to the invention, only the annular body 1 is shown in FIG. 1; the valve body (flap) itself has been omitted for reasons of clarity. The annular body 1 is provided with a circumferential groove 2 for fastening the cardiac valve prosthesis by means of a force fit in a fissure of the live tissue. The valve flap 3 shown in the open position in FIG. 3b and in the closed position in FIG. 3a has two spherical attachments 4 (only one is visible) which are snapped in place into respective recesses (bearing sockets) 5 and 6. During operation the ball members 4 journal in the respective socket 5, 6 and thus form a rotary bearing therewith. The spherical attachments 4 form opposite ends of an axis of rotation for the valve flap 3. The axis of rotation corresponds to a secant of a circular disc filling the interior of the annular body 1. In this way, the forces acting on the larger portion of the circular disc partitioned by the secant predominate so that the valve flap 3 is opened or closed by the flowing blood. In the closed position, the valve flap 3 lies on an abutment ledge 7 which is provided in the interior wall of the annular body 1 and which extends parallel to the periphery thereof. The abutment ledge 7 preferably extends in that body region between the recesses 5 and 6 which is further from the rotation axis than the other, opposite region between the recesses 5 and 6.
The interior surface of the annular ring 1 has an inwardly extending abutment ledge 7 shaped with a generally crescent configuration and the inner diameter of the annular ring 1 widens in the direction of flap valve 3 under the abutment ledge 7. In this way the elastic valve flap 3 can be inserted into the annular body by pressing it from a position oriented beyond the closed position, onto the abutment ledge 7 into the closed position from which, during operation, it is unable to be removed by hydrodynamic forces.
In order for the attachments 4 of the valve flap 3 to be able to enter the concave recesses 5 and 6 without significant deformation of the annular body 1, recesses 8 and 9 are provided which communicate with the recesses 5 and 6 to form a passage for the convex portions 4 toward the edge of the annular body. These supplemental recesses 8 and 9 may be provided by a milling tool having the dimensions of the convex portions 4. If the annular body 1 were made of plastic material and the valve flap including its attachments 4 were rigid, the attachments would shape themselves into the material in a corresponding manner.
The recesses 8 and 9 preferably end in the region of enlargements (humps) 10 and 11 of the annular body 1 so as to enlarge, in the region of the spherical attachments 4, the axial length of the annular body 1 for accommodating the concave, dome-shaped recesses 5 and 6. In the region of the humps 10 and 11, stops 12 and 13 are provided which bound recesses receiving the disc-shaped portion of the valve flap 3 in the open state (FIG. 3b). The stops 12, 13 ensure that the valve flap is unable to move beyond the vertical position. The stops 12 and 13 and their corresponding recesses have a shape which corresponds to the shape which would be formed by the valve flap being turned about 90° in the plastic annular body 1 from the closed position into the open position, with the larger diameter remote from the axis of rotation displacing the material of the annular body 1.
The edges which bound the recesses 8 and 9 and which are visible on the other side of the stops 12 and 13 in the plan view of FIG. 1, have an outwardly oriented slope so that, in the plan view, the stops 12, 13 together with the adjacent edges, are barb-shaped. Thus, upon insertion of the valve flap when in an open position, the edges of the valve flap slide over the edges adjoining externally the abutment faces 12 and 13 and come to rest in the region of the abutment faces 10 and 11. In this way, the valve flap can be inserted into the annular body without significantly deforming the latter, and by virtue of the effect of the abutment faces 12 and 13, the valve flap, when in an open state, can no longer assume the position in which it was inserted. Insertion may also occur without deformation of the annular body, in which case the valve flap must merely be slightly bent so as to overcome the detent effect of the abutment faces 11 and 12. Since the deformation is able to take place uniformly over the entire diameter of the cardiac valve; no major local material stresses occur.
In FIGS. 3a and 3b, the region in which the valve flap 3 is able to freely pivot is shown by arrow A and the movement required to pivot it during insertion is shown by arrows B (FIG. 3a) and C (FIG. 3b).
FIG. 4 shows the surface layer structure of the annular body 1 according to a further feature of the invention. On the surface of the annular body 1, there is provided a pore-free coating 14 of amorphous silicon oxide or pyrolytic or amorphous silicon carbide (a-SiC:H) as a semiconductive material, formed as a precipitation product of a mixture including silane (SiH 4 ) and/or methane (CH 4 ) and whose surface 15 has an antithrombogenic configuration.
The coating 14 has a maximum thickness of between less than 1 μm and 10 μm and has a comparatively high modulus of elasticity as well as a relatively smaller elastic range. The surface 15 has a peak-to-valley height (roughness) of about 0.1 μm or less. The state density of the coating 14 lies in the region of the energy level of the protein states in blood, that is, at 10 18 cm -3eV- , or less. The configuration of the surface 15 prevents direct charge exchanges between coagulation-specific proteins and the implant surface.
In a further embodiment, the semiconductive layer 14 is a microcrystalline material, particularly amorphous silicon-nitride (a-SiN:H). The surface 15 of this embodiment has characteristics corresponding to the embodiment described above.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A cardiac valve prosthesis includes a rotatably mounted, disc-shaped valve flap which is provided with two outwardly oriented, convex attachments disposed opposite one another at the points of intersection of a secant with the edge of the disc. The valve also includes an annular body having on its interior wall first recesses for receiving the convex attachments to thus form a bearing socket for the valve flap. At its interior wall, the annular body is provided with second recesses which communicate with the first recesses to form a passage for the convex attachments during insertion thereof into the first recesses. | 0 |
TECHNICAL FIELD
This invention relates generally to monochromatic and color printing and more particularly to an improved method of reproducing color images using a novel process combination of ordered dithering and error diffusion in a parallel signal processing arrangement. This invention serves to improve the print quality of the reproduced color images, and it is operational at relatively high computational speeds.
BACKGROUND ART
Traditionally, digital color images have been converted to a hardcopy output from a color printer using either an ordered dither process or an error diffusion process. Both of these processes are generally well-known in the color image reproduction arts and have been described in many prior art references including, for example, U.S. Pat. No. 4,733,230 issued to Kurihara et al, U.S. Pat. No. 4,651,228 issued to Koch and U.S. Pat. No. 4,339,774 issued to Temple, all incorporated herein by reference. More recently, error diffusion techniques have been used in combination with gray scale assignment methods to achieve high resolution and high print quality color printed images in the field of color ink jet printing. One such process is described, for example, in my now allowed co-pending application Ser. No. 278,881 filed Dec. 2, 1988 and this process is entitled "Method and System for Enhancing the Quality of Both Color and Black and White Images Produced by Color Ink Jet Printers". This application is assigned to the present assignee and is also incorporated herein by reference.
In the ordered dither method of image reproduction, the decision to print or not to print a pixel at a given pixel location (x, y) within an intensity I(x, y) depends upon the value of the dithered matrix at a given location, D(x, y), where D(x, y ) is typically an "n" by "m" matrix. These matrix valves are preassigned in a given pixel sequence along both the x and y directions of a super pixel or reference matrix or "tile", and this super pixel or reference matrix consists of a chosen number of individual pixels. If the value of I(x, y) is greater than D(x, y) at any given individual pixel location on the super pixel reference matrix, then the pixel at location x, y is printed, otherwise it is not printed.
The main advantage of this conventional approach to ordered dithering is its simplicity, since it involves only repetitive threshold comparison on a pixel by pixel basis. Different methods of selecting the dither matrix D will lead to different output characteristics, and the selection of matrix size (n by m) will also influence the output print quality. This ordered dither method of image reproduction exhibits excellent computational speed and is capable of either a good gray scale resolution or a good spatial resolution, but not both. A large ordered dither matrix D will result in good gray scale reproduction but poor spatial resolution, whereas a small ordered dither matrix D will result in good spatial resolution and a poor gray scale reproduction.
Extending these conventional ordered dither approaches to color image processing, there are as many ordered dither matrix masks as there are numbers of color planes. Regardless of how many different masks are used, there will always be a situation where a given pixel must be turned on for more than one color plane. While this situation is acceptable for some printing processes, it may not always be acceptable for other printing processes such as ink jet printing where different colors of ink, when piled on top of one another, will result in poor color mixing or undesirable color bleed. In electrophotographic processes which do not use transparent toners, different colors of toners piled on top of one another will also result in poor picture quality. In order to resolve the above conflicts with both ink jet and electrophotographic printing, a large number of computational processes are required.
Ordered dither processes of the above type are further described in a textbook entitled Fundamentals of Interactive Computer Graphics by Foley and Van Dam, Addision-Wesley Publishing Company, Copyright 1982, incorporated herein by reference. See particularly Section 17.2.2 and pages 597-602 of this reference.
Error diffusion is a technique used to distribute the remainder information to the neighboring pixels surrounding a primary printed pixel. This remainder information represents the error between a printable gray scale number and the complete input image gray scale data truly representative of a scanned image. This error diffusion process is frequently carried out using a selected one of several well-known algorithms which are described in my above identified copending application Ser. No. 278,881 and also in an article by Floyd and Steinberg entitled "An Adaptive Algorithm For Spatial Gray Scale", Proceedings of the Society of Information Display, Vol. 17/2, 1976, incorporated herein by reference.
Color and monochromatic printing methods which employ only ordered dither processing or only error diffusion processing alone have been characterized by several distinct disadvantages. Whereas ordered dither processes are very fast in computational speed, a significant amount of gray scale information can be lost due to the above described thresholding technique. These ordered dither processes have also been characterized by excessive noise, poor spatial resolution, and poor low and high frequency responses. In addition, when using multiple color planes and when restricted to dot-next-to-dot (DND) formatting, the traditional method of ordered dither is difficult to implement and is inefficient in resolving the DND formatting requirement.
On the other hand, printing methods which use only error diffusion to the exclusion of ordered dither techniques are relatively slow in computational speed (e.g. 1/8 of the ordered dither computational speed) and will render an image with an objectionable artifact known in the color printing art as "worms". This artifact is caused by allowing the error number generated in the error diffusion process to accumulate during printing and by the failure to adequately distribute the error remainder drop counts to pixels surrounding the just printed pixel or super pixel.
SUMMARY OF THE INVENTION
The general purpose of the present invention is to provide a new and improved method and system for color and monochromatic printing which combines most of the advantages of both the ordered dither and error diffusion processes in such a manner as to provide the good detail and color rendering of error diffusion signal processing without the artifact of "worms". Furthermore, this system and method will simultaneously have the speed of an ordered dither process and with a much improved low frequency and high frequency response with respect to an ordered dither process alone. In addition, the present system and method will easily resolve the formatting restriction of dot-next-to-dot (DND) printing as well as operate satisfactorily if restricted by a maximum ink volume per unit area (V max ) of a printed media requirement to prevent or minimize paper cockleing. Thus, the present invention is useful in the reproduction of printed images having good "worm free" spatial resolution, good gray scale transitions, and a high computational speed.
In accordance with the present invention, there is provided a method and system for converting scanned color image information to hardcopy output and includes initially scanning a color image to generate information containing cyan, (C), magenta, (M), yellow, (Y), and black, (K) super pixel information for further processing. This information is added in separate color planes to obtain C sum , M sum , Y sum , and K sum information representative of the added super pixel information in each color plane. This information is then divided in each color plane to thereby obtain a quotient signal and a remainder signal in each color plane and identified as C Q , C R ; M Q , M R ; Y Q , Y R ; K Q , K R in each color plane. The remainder signal in each color plane is distributed through a closed loop error distribution system and recombined with the originally added pixel information in each color plane identified above. The quotient information resulting from the above division in each color plane is distributed in an ordered dither process to an ordered dither output matrix from which a printed color image may be derived.
Using this process and associated system, a combination of ordered dither and error diffusion signal processing and printing may be achieved to simultaneously derive a number of advantages from each process. As an example, if an ordered dither process requires a computational time of "X" and error diffusion process requires a computational time of 8X, the present invention will require a computational time of typically around 1.2X-1.3X.
In a preferred embodiment of the invention, each super pixel within a larger super pixel matrix (I, J) comprises m x n individual pixels, and the chosen gray level normalizing factor is equal to 2 8 for an eight bit data representation. Since this normalizing factor has a base value of 2, this method and signal processing system possesses an exceptional computational speed. In contrast to known prior error diffusion techniques, the error remainder number of drops in the present process is diffused into assigned super pixels adjacent to the primary or just-printed super pixel. This minimizes the possibility for an undesirable accumulation of error data, and there is less computational effort involved in such super pixel error diffusion in comparison to single pixel error diffusion.
In accordance with the preferred embodiment described below, a single data processing methodology or code may be used to handle both the ordered dithering process and the error diffusion process. This novel feature in turn simplifies the construction and cost of implementing the system and method for carrying out this invention.
Accordingly, an object of this invention is to provide a new and improved method and system in the type described which combines many of the best performance characteristics of error diffusion with many of the best performance characteristics of ordered dither processing in a hybrid image conversion process. This process is useful to improve the overall print quality and resolution of color images reproduced on a hardcopy output.
Another object is to provide a new and improved method and system of the type described which eliminates the artifact of "worms" frequently characteristic of error diffusion image conversion processing.
Another object to provide a new and improved method and system of the type described which is operative at relatively high computational speeds.
Another object to provide a new and improved method and system of the type described which produces hardcopy output images having good spatial resolution, a reasonably good gray resolution, and good low frequency and high frequency response characteristics.
Another object is to provide a new and improved method and system of the type described which is compatible with both dot-on-dot (DOD) and dot-next-to-dot (DND) formatting.
A novel feature of this invention is the provision of a system and method for use in both monochromatic and color printing which simultaneously employs ordered dithering and error diffusion in a parallel signal processing scheme useful to retain a maximum amount of information in a hardcopy replication of a scanned image. Ordered dither quotient information is printed in a series of predetermined super pixel reference matrices to produce a hardcopy output, and remainder information associated with this quotient information is dispersed in a closed loop feedback process and system and recombined with incoming image information. This is done in a manner designed to minimize the loss of information during reproduction of a scanned image as hardcopy output from the system.
Another feature of this invention is the provision of a method and system of the type described which is operative to generate ordered dither quotient and remainder data representative of a scanned image. The system is also operative to print the quotient data information in a predetermined priority sequence of individual pixel locations within a larger or super pixel reference matrix or mask.
Another feature of this invention is the provision of a method and system of the type described which is operative for generating quotient and remainder information for each of a plurality of color planes, such as the cyan (C), yellow (Y), magenta (M), and black (K) color planes. Then, quotient data for each color plane is printed in a super pixel reference matrix or mask using this approach, and dot-on-dot (DOD) printing is never forced as in the prior art case where a super pixel reference matrix or mask is used for each color plane. Additionally, voids may be retained in a printed super pixel in order to eliminate or reduce color bleed as in the case of ink jet printing. This was not possible in prior art ordered dither methods which required a separate super pixel reference matrix (also referred to as a tile or mask) for each color plane.
Another feature of this invention is the provision of a method and system of the type described which possesses novelty in the ordered dither operation per se and apart from its combinational novelty with error diffusion processes. In this novel ordered dither approach, ordered dither quotient information is preassigned to individual pixels within a larger super pixel reference matrix. All of this quotient information is used in generating hardcopy output and is not compared as in conventional ordered dither processes in a piece-wise fashion using reference matrix or mask thresholding techniques where substantial amounts of image information are lost.
Another feature of this invention is a provision of a novel error diffusion process per se which is operative to disperse error remainder information into a plurality of super pixels surrounding a just printed super pixel from which error remainder information is extracted. This technique stands in significant contrast to conventional error diffusion processes where only individual pixels receive error distribution data from a just printed pixel or super pixel.
Another feature of this invention is the provision of a novel parallel signal processing system which is operative in a unique, cooperative and elegantly simple manner to provide image conversion utilizing a common algorithm suitable for handling both the error diffusion and ordered dither processes as described further herein.
Another feature of this invention is the provision of an improved process and system of the type described which is capable of limiting the printed drop or dot volume to a predetermined maximum print volume, V max , such as may be required in ink jet printing applications. This technique has been used to prevent paper cockleing in ink jet printing applications and to limit the amount of toner introduced onto a given print media in electrophotographic printing applications.
Another feature of this invention is the provision of a signal processing system of the type described which is uniquely adapted and suitable for use and operation with an output ordered dither matrix using either cluster or disperse pixel assignment methods. These methods are capable of handling all cases of dot-next-to-dot (DND) and dot-on-dot (DOD) formatting, including pixel voids, in a unified manner.
The above objects, advantages and novel features of this invention will become better understood from the following description of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram of an image conversion system which may employ the new and useful system and method according to this invention.
FIG. 2 illustrates an I, J array or index of scanned super pixels, with each super pixel having its own i-j index of individual pixel information to be processed in accordance with the present invention.
FIG. 3A is a schematic and descriptive flow chart depicting the data processing methodology and sequence of steps used for controlling the operations of error diffusion, ordered dither and pixel assignment according to the present invention.
FIG. 3B is a descriptive flow chart depicting the data processing methodology used in imposing a maximum drop or dot count limit on each of the printed color planes.
FIG. 3C is a functional electrical block diagram which illustrates in more detail the signal process sequence described in FIG. 3B.
FIGS. 4A, 4B, and 4C illustrate a pixel thresholding process used in conventional prior art ordered dither methods of printing.
FIGS. 5A, 5B and 5C illustrate an extreme case of pixel assignment in conventional ordered dither printing where a maximum amount of information is lost due to under-printing in the printing process.
FIGS. 6A, 6B, and 6C illustrate a pixel assignment process using conventional ordered dither printing where a maximum amount of information is lost through over-printing rather than under-printing.
FIGS. 7A and 7B illustrate a pixel assignment process using conventional ordered dither printing for multiple color planes.
FIGS. 8A and 8B illustrate a dot-next-to-dot (DND) pixel assignment process for multiple color planes using the ordered dither pixel assignment process according to the present invention.
FIGS. 9A and 9B illustrate another type of DND ordered dither matrix and DND pixel assignment process according to the present invention for printing in multiple color planes.
FIGS. 10A and 10B illustrate another type of DND ordered dither method of printing in accordance with the present invention which is useful for leaving voids in a printed pixel matrix.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a scanner 10 may be used to convert a color image into digital gray scale data for application to an additive red-green-blue (R-G-B) format conversion stage 12. The R-G-B output data from the format conversion stage 12 is applied as indicated to the subtractive color primaries stage 14, also known as the cyan-yellow-magenta (C-Y-M) color conversion stage 14 in a well-known manner and may include up to 100% undercolor removal to obtain black, as is also well-known. A chromatic color (black) cannot be easily made by mixing Y-M-C ink colors, and such mixing will also increase the amount of ink consumed as well as fail to obtain a pure black color. Therefore, the black ink created by YMC colors is preferably replaced by pure black (K), and this replacement and the generation of pure black is known in the art as undercolor correction or undercolor removal (UCR). Thus, the use of 100% undercolor removal is for the purpose of both minimizing ink consumption and improving resolution of the image reproduced on hardcopy output.
The output of the C-Y-M color conversion stage 14 is a digital data stream which is applied to the hybrid error diffusion (ED) and ordered dither (OD) stage 16, and the hybrid ED/OD stage 16 in turn drives a color printer 18, such as, for example, a thermal ink jet color printer. With the exception of the hybrid ED/OD stage 16, the general functional arrangement of the image scanning and reproduction system of FIG. 1 is generally well known in the image processing arts. One type of image processing operation of such a system is described, for example, in the March 1987 issue of BYTE Magazine in an article by B. M. Dawson entitled "Introduction To Image Processing Algorithms" at page 169 et seq. Such image processing capability and corresponding system operation is also described in a publication by Gary Dispoto et al entitled Designer's Guide to Raster Image Printer Algorithms, First Edition, December 1986, Copyrighted by the assignee Hewlett-Packard Company in Palo Alto, Calif. Both of these latter references are incorporated herein by reference.
Referring now to FIG. 2, there is shown a large matrix of super pixels identified by the I, J indices and consisting of individual super pixels identified by the m-n indices. Each of the m-n super pixels contains sixteen individual i-j pixels. This figure provides the x-y matrix information which is used in some of the mathematical notation of the present specification, and the m-n super pixel in FIG. 2 is a typical 4 by 4 or sixteen segment super pixel. In practicing the present invention, it has been found that 6 by 3 or 8 by 4 super pixels provide a good compromise or tradeoff between good computational efficiency on the one hand and good output picture quality on the other.
Referring now to FIG. 3A, there is shown a method of processing one super pixel in accordance with the invention. At the initial step in FIG. 3A, the added drop count numbers for each of the C, M, Y, and K super pixel values (C sum , M sum , Y sum , and K sum ) are totalled and then processed to a division step or stage 28. In the notation of FIG. 2 above, these sums for each color plane are given as follows: ##EQU1## Where K ij , C ij , M ij , and Y ij are the pixel values of black, cyan, magenta, and yellow, respectively, and K r , C r , M r , and Y r are the previous super pixel residual values of black, cyan, magenta, and yellow, respectively.
The primary color pixel sums above are divided in step 28 by a normalizing factor of 2 8 , and this is done in order to obtain a normalized quotient for each primary color summed and also to obtain an error residual for error diffusion as indicated in step 30 for an 8-bit data representation. In step 30, the error residuals are combined with the previously summed information (as further indicated below in FIG. 3C), and the quotient output from step 28 is processed in parallel with the error diffusion in step 30 to an output super pixel selection and color printing step 32.
The output step or stage 32 contains therein an adjustment control stage 34 which is shown in the functional block diagram of FIG. 3B. The function of the adjustment control stage 34 is to count the total number of C, M, Y, and K dots in each color plane and compare this total number with a predetermined maximum allowed number or volume of drops, defined as a maximum volume V max . However, V max is not intended to refer only to a maximum volume, but rather to any upper limit on a dot count. If V max is exceeded, then the next highest allowable and available number of drop or dot counts for the C, M, Y, and K sums in each color plane is provided, and the difference between the latter two totals provides a basis for an error diffusion into super pixels surrounding a primary or just-printed pixel as described further below. When the total drop count sum for C, M, Y, and K is finally selected to be equal to or less than V max (or the dot count maximum number), the output signal of the adjustment control stage 34 performs an output ordered dither operation in accordance with the novel pixel assignment process described and claimed herein.
The adjustment control stage 34 includes therein a total dot count stage 37 which is operative to compare an incoming dot count signal with a preassigned maximum dot count number V max and to generate a "yes" or "no" output signal on one of its two output lines 38 and 39 as indicated. If the total dot count does not exceed V max , a signal is produced at the input to the pixel assignment and ordered dither matrix stage 40 for providing the ordered dither printing and super pixel matrix assignment used in the production of a color hardcopy output. If, however, the total dot count in stage 37 exceeds V max , a signal is generated on line 38 at the input of stage 41 where the color plane of the highest dot count is identified, and a corresponding output signal is then generated and applied to the input of the next stage 42 where the dot count of the previously read color plane is decremented by one.
The output signal from stage 42 is utilized to drive an error diffusion stage 43 which distributes the decremented error signal to super pixels adjacent to the just mentioned super pixel. The error diffusion stage 43 then generates an input signal to the input of the next dot count update stage 44 which is operative to update the total dot count and again provide an output signal at the input of another or second dot count comparison stage 45. The comparison stage 45 then compares the new updated dot count with V max and generates an output "no" signal on line 46 and applied at the input of the ordered dither matrix stage 40 if V max is not now exceeded. If V max is still exceeded, the comparison stage 45 generates an output "yes" signal by way of feedback line 47 which is applied to the input of the color plane identification stage 41. This stage 41 again identifies the color plane of the next highest dot count to start the V max comparison process all over again until a "no" output signal on line 46 is ultimately generated as described above.
Referring now to FIG. 3C, the super pixel scanner 36 contains stages 10, 12, and 14 of FIG. 1 above, and thus the data line 15 in FIG. 3B corresponds to the data line 15 in FIG. 1. This data line 15 is connected as shown to drive the error diffusion and ordered dither stage 16 which is illustrated in functional block diagram form in FIG. 3B. The data line 15 provides four available data inputs 48, 50, 52, and 54 to the respective cyan, magenta, yellow, and black pixel adders 56, 58, 60, and 62 in the four color planes shown. The above four primary colors of the total pixel information in all of the scanned super pixels in FIG. 2 above are generated respectively on the output data lines 64, 66, 68, and 70. These lines are connected as shown to drive the four divider stages 72, 74, 76, and 78 in the cyan, magenta, yellow, and black parallel processed color planes. The cyan, magenta, yellow, and black pixel information dividers 72, 74, 76, and 78 each have a respective quotient output data line 80, 82, 84, and 86 for receiving the C Q , M Q , Y Q , K Q quotient data. Additionally, these divider stages 72, 74, 76, and 78 have output remainder data lines 88, 90, 92, and 94 which receive the remainder signals C R , M R , Y R , K R . These latter signals are fed, respectively, into a feedback loop containing black, yellow, magenta, and cyan remainder lookup tables (LUTs) 96, 98, 100, and 102. Each of these lookup tables 96, 98, 100, 102 is used to provide the gray scale information necessary to generate remainder error diffusion signals on the output data lines 104, 106, 108, and 110 respectively. These signals are then applied to the error distribution stages 112, 114, 116, and 118 for the four, black, yellow, magenta, and cyan color planes in the error diffusion feedback loop shown. These error distribution stages 112, 114, 116, and 118 have their output data lines 120, 122, 124, and 126 connected as shown to recombine the error distribution signals on these data lines 120, 122, 124, 126 with the summed information in the four color pixel adder stages 56, 58, 60, and 62, respectively.
The quotient output data lines 80, 82, 84, and 86 leading from the cyan, magenta, yellow, and black divider stages 72, 74, 76, and 78 respectively are connected as shown to a plurality of quotient lookup tables 128, 130, 132, and 134 for each of the black, yellow, magenta, and cyan color planes as indicated. Each of the quotient lookup tables 128, 130, 132, and 134 has an output data line 136, 138, 140, and 142 connected as shown to the adjustment control stage 34 described above in FIG. 3A. The adjustment control stage 34 is utilized as previously described to decrement the drop count output signal totalled from lines 136, 138, 140, and 142 to a value equal to or less than V max in order to provide an acceptable maximum drop count number (signal) on the output data line 144 from the adjustment control stage 34. This signal is used to drive the output ordered dither matrix stage 146 from which a color image output signal is derived from the output terminal 148.
In accordance with the broad teachings of the present invention, the ordered dither matrix stage 146 may utilize any suitable ordered dither process which is compatable with error diffusion processes of the type described herein. Since the broad combination of ordered dither and error diffusion is novel in both the method and system claim formats as presented herein, it is to be understood that the present invention includes within its scope any combination of ordered dither and error diffusion within the scope of the appended claims. However, it should also be understood and appreciated that one specie of the present invention is a new and improved ordered dither method per se which in many of its aspects is believed far superior to any known conventional ordered dither techniques.
In order to demonstrate such superiority of the ordered dither process of the present invention, reference will first be made to FIGS. 4A-4C, 5A-5C, 6A-6C, and 7A-7B in order to demonstrate how image information is undesirably lost when using conventional thresholding type of ordered dither methods. For this demonstration, these three figures show a monochromatic case or example, but the superiority of the present ordered dither process is equally applicable to color printing. Then, after this discussion of conventional ordered dither methods, reference will then be made to FIGS. 8A-8B through FIGS. 10A-10B which serve to illustrate the preferred and novel ordered dither matrix selection method in accordance with the present invention.
Referring now to FIGS. 4A, 4B, and 4C, FIG. 4A is a two by two four quadrant super pixel with each quadrant thereof having an assigned intensity level from the scanned image. In FIG. 4B there is shown a dither matrix or reference tile or mask with each quadrant therein having a preassigned threshold number. The image super pixel in FIG. 4A is simply laid over the reference mask or tile in FIG. 4B and only the upper right hand quadrant in the super pixel of FIG. 4C is printed. That is, only the pixel intensity level in the upper right hand quadrant in FIG. 4A exceeds the upper right hand quadrant in the reference tile of FIG. 4B. Thus, the actual information in FIG. 4A is 400/1024, but the printed information in FIG. 4C is 255/1024. Thus, the loss of information in the thresholding ordered dither process illustrated in figure is equal to 145/1024.
Referring now to FIGS. 5A, 5B, and 5C, this process illustrates the case where a maximum amount of information is lost during thresholding, resulting in an empty or underprinted pixel as shown in FIG. 5C with too little information. This thresholding process may then be compared to the maximum loss of information in an over-printing case in FIG. 6A through 6C where all of the four quadrants in FIG. 6C are printed with "too much information". Again, this is the result of the imprecise nature of the conventional ordered dither threshold process.
Referring now to FIGS. 7A and 7B, it is believed that an explanation and understanding of these two figures illustrating a conventional ordered dither process will be most useful in an understanding and appreciation of the significant advantages of the present invention. FIGS. 7A and 7B illustrate a scenario of thresholding during color printing in the four color planes of cyan, magenta, yellow, and black wherein the thresholding not only causes a significant information loss in the color planes, but also produces a combined output geometry of the most undesirable print pixel assignment for a 2 by 2 super pixel.
The top row in FIG. 7A shows the actual pixel values for a scanned color image for the four 2 by 2 super pixels in the four C, M, Y, and K color planes. The second row in FIG. 7A shows the reference pixel values for the reference dither matrix or tile to which the pixels in the first row are compared to generate only the output information indicated in the third row of FIG. 7A. This output information is generated only in the upper right hand quadrants of the third row where the actual received pixel value exceeds the dither matrix values.
The result of the combined output for FIG. 7A is to print C, M, and K color dots all in the upper right hand quadrant of FIG. 7B, and even the layman can easily see that, in addition to the loss of information produced by the thresholding process of FIG. 7A, this loss of information is combined with the poorest selection of quadrant printing in FIG. 7B to further degrade the print quality of the reproduced output image.
In contrast to the thresholding and pixel overlay printing process of FIGS. 7A and 7B above, the following example is given to better illustrate the quotient and residual signal processing according to the present invention wherein not only all of the quotient information is retained in printing an output pixel, but this feature is combined with an optimum pixel assignment priority selection sequence. This is done in printing the output matrix so as to simultaneously maximize print quality with no loss of quotient information. As previously indicated, the error diffusion processes used for distributing the error residuals are well-known in the art and are therefor not described in detail herein.
Assume that an individual super pixel has the following values: K sum =700; C sum =700, M sum =700; Y sum =0. For 256 levels of gray scale, or 2 8 =256 as a normalizing factor then K Q , C Q , M Q are all each equal to 2 and K R , C R , and M R are all each equal 188. And, Y Q , Y R both equal 0 in this example. Assuming there is no V max limit imposed on this example, then the printed output matrix might, for example, be arranged as indicated in FIG. 8A with two black dots printed in both of the two upper quadrants of the super pixel in FIG. 8A, and a cyan and a magenta dot printed in both of the two lower quadrants of the super pixel in FIG. 8A.
Assume now in our example that we have imposed a V max equal to four, such as for example to minimize paper cockleing by excessive ink volumes in the field of ink jet printing. Thus, since the sum of K Q plus C Q plus M Q in our above example equals 6, this means that this total of six dots for our 2 by 2 super pixel must be reduced to four. This may be done for example by reducing K Q and C Q to one dot each, thereby increasing the K R remainder to 188 plus 256 or 444 and the C R remainder to 188 plus 256, also 444. After this increased remainder is distributed to surrounding super pixels through the process of error diffusion as described above, the printed pixel sequence might be as indicated in FIG. 8B wherein one black dot and one cyan dot are now printed in the two upper quadrants of the 2 by 2 super pixel, and again the two magenta dots are printed in the lower two quadrants or pixels of the super pixels, thereby maintaining a V max limit of four dots as indicated above.
FIGS. 9A and 9B illustrate the pixel assignment process in accordance with the present invention where all of the quotient information is printed in FIG. 9B in the pixel assignment priority sequence in FIG. 9A, resulting in no loss of color quotient information. FIG. 9A gives a 1-9 printing sequence of the nine pixels which form the super pixels, and the inside-to-outside clockwise rotation of these numbers is known in this art and technology as "cluster" pixel assignment or geometry. Another available outside-to-inside pixel assignment which might be used, but not shown in the drawings, is also known as the "cluster" type of pixel assignment of dots to be printed within a super pixel. Yet another available pixel arrangement having two consecutive sequences of pixels to be spread at a maximum possible distance within a super pixel is known in the art as a "disperse" type of pixel arrangement. Thus, for K, C, M, and Y dot count of 1+3+2+0=6 as indicated in these two figures, the K dot is printed in the center of "1" cluster pixel assignment position, the three cyan dots are next printed in sequence in the "2", "3", and "4" positions, and the two magenta dots are then printed in sequence in the "5" and "6" positions. Therefore, not only is all of the color quotient information preserved and not lost as in prior art ordered dither schemes, but the above cluster printing sequence of dot-next-to-dot printing tends to optimize the overall print quality of the output hardcopy converted image.
This dot-next-to-dot (DND) printing is also compatable with the use of void quadrants such as the lower left hand quadrant identified in FIG. 10A and 10B, and these techniques of leaving one or more pixels void are useful in certain types of ink jet printing applications where it is desired to minimize or eliminate color bleed during certain types of color printing applications.
Various modifications may be made in the above described embodiments without departing from the spirit and scope of this invention. For example, whereas the word "drops" or "dots" have been used frequently in the context of inkjet printing or the like, it should be understood that the present invention is broadly applicable to other types of printing processes such as electrophotographic or laser jet printing. Therefore, the word "drops" or "dots" are understood to be used interchangeably with the various other pixel selection in printing processes of other printing methods such as electrophotographic printing.
Also, other terms such as "V max " indicating a volume maximum in ink jet printing should also be understood to refer to an upper dot count limit when used in the context of other types of printing such as electrophotographic printing. | A method and system for color and monochromatic printing wherein ordered dither and error diffusion processes are combined to provide high quality printed images with good spatial resolution, good gray scale transitions, good low frequency and high frequency responses and a high computational speed. Using this process, gray scale numbers representative of a scanned image are summed for each super pixel of the scanned image and divided by a chosen gray level normalizing factor. This division operation is done to obtain a normalized ordered dither quotient number of drops (dots) to be printed in super pixels and to further obtain an error remainder number of dots to be dispersed to surrounding super pixels. The normalized ordered dither quotient number of dots are printed in pre-assigned individual pixels within printed super pixels, and the error remainder number of drops are diffused to other pre-assigned surrounding or adjacent super pixels. In this manner, a combination of ordered dither and error diffusion signal processing and printing is achieved to simultaneously take advantage of some of the best characteristics of both types of signal processing printing. In color printing, the above operation is carried out in each of a plurality of separate color planes, and all of the quotient information is retained and printed in a predetermined priority sequence for each color plane. | 7 |
This is a continuation-in-part of Ser. No. 842,394 filed Oct. 17, 1977 and now abandoned.
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to the detection of various gases in the atmosphere, and more specifically to measuring time weighted exposures of those gases with a chemically integrating dosimeter.
2. Prior Art Statement
High sensitivity determinations of various gases in the workroom atmosphere have been made necessary by the establishment of federal standards for industrial air. See, Federal Register, Vol. 36, No. 105, May 29, 1971. Although a wide variety of methods has been proposed and used for the determination of the many gases subject to these federal standards, the present invention relates specifically to the measurement of the following gases in workroom air at atmospheric pressures: hydrogen sulfide, H 2 S; sulfur dioxide, SO 2 ; hydrogen chloride, HCl; ammonia, NH 3 ; hydrogen fluoride, HF; and hydrogen cyanide, HCN. The presence of these gases in sufficient quantities in industrial air can be injurious to human health. For example, hydrogen sulfide, H 2 S, is a toxic contaminant often encountered in the industrial processing of gas and gas streams. Exposure to H 2 S gas in even small amounts can result in olfactory paralysis in less than fifteen minutes. Longer periods of exposure result in sickness and death. See, Hydrocarbon Processing & Petroleum Refiner 42:115, April, 1963. Sulfur dioxide gas, SO 2 , is a major source of atmospheric pollution. Because of its corrosive and poisonous characteristics, sulfur dioxide is an extremely dangerous pollutant. The gas causes irritation and inflammation of the eyes and respiratory paralysis if present in sufficient concentration. Concentrations of approximately 1 ppm are believed injurious to plant life.
Threshold limit values (TLV), i.e., the time weighted average for maximum allowable exposure over an eight-hour day or a forty-hour week, have been prescribed for each of the gases listed above. See, "TLV's for Chemical Substances in Workroom Air," adopted by American Conference of Governmental Industrial Hygienists (ACGIH) for 1976. In particular, the current threshold limit value (TLV) for H 2 S is 10 parts per million (ppm). Exposures up to 15 ppm are permissible for H 2 S if the time weighted average remains below the TLV of 10 ppm. The current threshold limit value (TLV) for SO 2 and HCl is 5 parts per million (ppm). Short term exposure is also limited to 5 ppm. The current TLV for ammonia, NH 3 , is 25 ppm. Short term exposure is limited to 35 ppm. The TLV for hydrogen cyanide, HCN, is 10 ppm, with allowable short term exposure at 15 ppm. The TLV for hydrogen fluoride, HF, is 3 ppm, with short term exposure also at 3 ppm.
Since these federal regulations require the measurement of time weighted exposure of workers to gases, techniques which make cumulative, i.e., time integrated, determinations of gas concentrations are desirable. Devices which measure concentrations at a particular instant are inconvenient since repeated measurements, followed by arithmetic integration, are required to arrive at a cumulative exposure value. Even devices which continually measure gas concentrations are limited by the need for arithmetic integration of results over time. Arithmetic integration of a series of measurements at specific time intervals is misleading if the interval between measurements is large enough that variations in gas concentrations are not detected. The expense of frequent measurements, coupled with the requirements for time integrated exposures, illustrates the limitations of present systems for determining long term exposure to gases.
One such present system, a means for measuring hydrogen sulfide gas, has been disclosed by Riseman, et al, and described in U.S. Pat. No. 3,915,831. A hydrogen sulfide, H 2 S, sensing cell uses a sulfide-ion sensitive electrode, in conjunction with a reference electrode. The permeation of H 2 S across a single membrane into a reference solution is determined by potentiometrically measuring the change in sulfide ion concentration in the solution.
One "Method of Determining Sulfur Dioxide and Sensing Cell Therefor" has been disclosed by Kreuger, Frant, and Riseman in U.S. Pat. No. 3,803,006. The method uses a hydrogen ion sensitive glass electrode in conjunction with a Ag/AgCl reference electrode. SO 2 permeates across a single membrane into an aqueous solution of sulfite or bisulfite salt, where the SO 2 dissolves and reacts with H + ion to form sulfite and bisulfite ions. SO 2 is determined by potentiometrically measuring the change in H + ion concentration.
Chand has disclosed an apparatus for measuring sulfur dioxide in U.S. Pat. No. 3,622,488. SO 2 permeates across a single semipermeable membrane into a dilute sulfuric acid electrolyte. Electro-oxidation of sulfur dioxide to SO 4 -2 occurs at a noble metal sensing electrode, and generated current is measured between this electrode and a counter-electrode. While SO 2 concentration is thereby determined, the device does not measure time integrated exposure to SO 2 .
Reiszner and West describe a method for Determination of Sulfur Dioxide in "Environmental Science & Technology," Vol. 7, No. 6, p. 526, June 1973. SO 2 gas permeates through a single gas permeable membrane into a sodium tetrachloromercurate (II) internal solution, forming the stable dichlorosulfitomercuate (II) complex. The dichlorosulfitomercurate (II) complex is extremely sensitive to direct sunlight and must be protected from solar radiation through the use of a light-shield mounting box. SO 2 concentration is then determined by the lengthy and complex West-Gaeke procedure, described in ASTM 02914-70 T.
A measuring cell for determining the concentration of SO 2 in a fluid has been disclosed by Dahms in U.S. Pat. No. 3,756,923. The cell includes an electrode covered with a thin layer of an electrolyte containing silver ions, and a counter electrode. When a voltage is applied across the electrodes, the resulting current is a measure of the concentration of SO 2 . In one of its forms, the electrolyte is separated from the sample fluid by means of a single membrane, composed of silicon rubber of polytetrafluorethylene. Disposed between the membrane and the electrolyte can be a porous spacer which is ion permeable and wettable. The function of the porous spacer is to provide a geometrically well-defined layer of electrolyte on the electrode. The cell does not make time integrated measurements of SO 2 gas.
A sulfur oxide meter for measuring changes in SO 2 activity directly in an electrochemical cell has been disclosed by Salzano, et al, in U.S. Pat. No. 3,718,546. Both a reference and a sample oxygen bearing electrode are exposed to a fused salt electrolyte. One or more membranes which are porous to a cation common to the electrolyte are used to isolate the reference and sample gas electrodes from each other. The SO 2 activity is determined by measuring the output electromotive force (EMF) ofthe cell, which is a function of the difference in activities between the SO 2 in the reference gas and that in the test sample. The device
For measurements of ammonia, NH 3 , an electrode has been disclosed by Riseman, et al, in U.S. Pat. No. 3,830,718. The standard electrolyte solution comprises a saturated aqueous solution of an ammonium salt of a strong acid having a pK of not more than 3, the salt having an aqueous solubility at room temperature such that the ammonium ion concentration is about 0.001 M to 1 M. A single microporous hydrophobic membrane with a porosity sufficiently great so as to readily pass ammonia gas but not great enough to permit any appreciable passage of liquid or ions, separates the electrolyte from the sample gas. The electrode provides real time, but not integrated, determinations of ammonia concentrations.
An ammonia sensor has been disclosed by A. Strickler, et al, in U.S. Pat. No. 3,649,505. An electrochemical cell comprises a hydrogen ion sensitive electrode and a reference electrode joined by an ammonium-ion containing electrolyte. The electrodes and electrolyte are separated from the sample being analyzed by a single microporous hydrophobic membrane, highly permeable to ammonia gas and substantially impermeable to liquid and ions. In a preferred form, a second inner hydrophilic membrane is interposed between the first membrane and the internal electrolyte. The second membrane is ion permeable and may be composed of very thin cellophane or filter paper. The inner membrane ensures that an electrolyte film is provided between the outer membrane and the ion sensitive electrode.
A dosimeter for measuring nitrogen dioxide has been disclosed by Ferber, et al, in U.S. Pat. No. 3,992,153, which makes arithmetically determined time weighted average measurements of NO 2 . The nitrogen oxide to be measured passes through a single, gas-permeable, liquid-impermeable membrane into an internal gas-absorbing solution. The rate of entry of gas molecules into the absorbing solution is controlled by the permeability of the membrane and by the concentration of the ambient gases. The gas molecules stoichiometrically react with the internal solution to form NO 3 - ion. The change in NO 3 - concentration is monitored with an ion sensor and the ambient NO 2 gas concentration can be back calculated. Ferber also discloses the use of a glass-fiber filter impregnated with acidic sodium dichromate to convert NO to NO 2 by oxidation. In this manner, exposure to NO can be determined. This filter is disposed externally to the membrane.
A gas-sensing electrochemical cell for measuring nitrogen dioxide dissolved in a sample solution has been disclosed by Kreuger, et al, in U.S. Pat. No. 3,830,709. The cell comprises a potentiometric hydrogen ion-sensitive electrode and a reference electrode, both in contact with an internal standard solution comprising an aqueous acid solution of a nitrite salt. A single hydrophobic gas permeable membrane separates the sample solution from the internal solution. The cell does not make time integrated measurements of NO 2 gas.
Several other techniques for the general measurement of atmospheric gases have been disclosed in the art. For example, a polarographic sensor for measuring atmospheric gases, composed of a pair of electrodes joined by an electrolyte has been disclosed by Krull, et at, in U.S. Pat. No. 3,718,563. A multi-layer gas permeable, essentially ion impermeable membrane separates the electrodes and the electrolyte from the sample medium. The outer layer of the membrane is preferably formed of silicone rubber. The inner layer is formed of a material less permeable to gas and water vapor than the outer membrane.
Two other patents which relate to applicant's invention are described below. An electrochemical gas analyzer is disclosed by Laurer in U.S. Pat. No. 3,767,552. The anode and cathode are in contact with each other by means of an internal electrolyte. Separating the two electrodes is a disc, permeable to liquids but impermeable to solids, which prevents particles of the anode from contacting the cathode. A gas-permeable, liquid impermeable membrane separates the electrodes and the electrolyte from the sample to be analyzed. A second flexible, liquid impermeable expansion membrane is disposed internally to both the electrolyte and the electrodes.
An electrolytic sensor to measure carbon dioxide, CO 2 , with water diffusion compensation has been disclosed by Riseman, et al, in U.S. Pat. No. 3,357,907. A single membrane selectively permeable to gases separates an electrochemically active sample species from an electrode which is sensitive to an ionic concentration in an internal electrolyte placed between the electrode and the membrane. This ionic concentration is a fundtion of the concentration of the sample species. In one form of the invention, spacing means, such as a cellophane film, is disposed internally to the membrane. The spacing means is permeable to gases and water, and is wettable.
SUMMARY OF INVENTION
The present invention contemplates a chemically integrating dosimeter, composed of a dual membrane system and an internal electrolyte solution wherein the outer membrane is a gas permeation rate controlling membrane and the inner membrane is a microporous hydrophobic protective membrane. The inner membrane is interposed between the outer membrane and the internal electrolyte solution. The object of the invention is to provide a small, simple, and lightweight dosimeter with long shelf life that makes high sensitivity time weighted average determinations of gases in the atmosphere such as, but not limited to: hydrogen sulfide, H 2 S; sulfur dioxide, SO 2 ; hydrogen chloride, HCl; ammonia, NH 3 , hydrogen flouride, HF; and hydrogen cyanide, HCN.
The dosimeter is comprised of an outer and inner membrane and an electrolyte solution disposed internally to the inner membrane. The outer membrane is composed of a material substantially liquid impermeable. This material is selected so that the permeation rate of the gas species to be measured is significantly slower than the diffusion rate of the same gas species in air. The inner protective membrane is hydrophobic and microporous, as well as liquid water impermeable. It serves two purposes, the first of which is to protect the outer membrane from direct chemical attack by the internal electrolyte. The second purpose is to essentially eliminate precipitate formation and/or deposition on the outer membrane and hence any effect on its permeability. While precipitates may be deposited on the inner membrane, the pores of the membrane are large enough to preclude any but long term changes in the effective permeability rate of the inner membrane.
The chemical composition of the internal electrolyte is selected so that upon entry of the gas to be measured a chemical reaction occurs between said gas and the electrolyte such that the concentration of the gas is brought to zero within the electrolyte. At the same time this reaction also causes a change in the concentration of a selected ion. By electrochemically measuring the change in concentration of the selected ion, the amount of the gas entering the dosimeter during the exposure period is determined.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more full understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawing wherein a diagrammatic, side-elevational, cross-sectional view of a preferred from of the present invention is shown.
DETAILED DESCRIPTION OF THE INVENTION
In the drawing, the two membrane dosimeter is depicted as comprising an outer membrane 10, and inner membrane 30, through which ambient gas species 12 permeates. Outer membrane 10 is physically separated from inner membrane 30 by O-ring 46; in other examples, they can be in direct physical contact. The placement of both is made secure through the use of structural base 40, and annularly mounted cap 42. Clip 48 is used to attach the dosimeter to clothing. Electrolyte 20 is disposed internally to inner membrane 30.
The gas species 12 to be measured by the dosimeter permeate through the outer membrane 10, through the inner membrane 30, and are absorbed in internal electrolyte 20. By the term "absorbed" used here and in the claims it is meant that a chemical reaction occurs between the gas to be measured and the electrolyte such that (a) the concentration of the gas in the electrolyte is brought to zero and (b) the concentration of a selected ion within the electrolyte is altered. By measuring the change in concentration of the ion, the amount of gas absorbed can be determined. The dosimeter is therefore chemically integrating in the sense that the reaction within the electrolyte begins upon exposure to the gas to be measured and continues throughout the exposure period. An integrated total concentration for exposure period is measured. As will appear more fully herein, the dual membrane structure can be used in the determination of i.e., the following gases in the atmosphere: hydrogen sulfide, H 2 S; sulfur dioxide, SO 2 ; hydrogen chloride, HCl; ammonia, NH 3 ; hydrogen fluoride, HF; and hydrogen cyanide, HCN.
Outer membrane 10 is composed of material substantially permeable to gases and substantially impermeable to liquids. Silicone rubber and sillicone polycarbonate copolymer are examples of suitable membrane materials. Liquid permeable membranes could also be used but as these can be subject to wetting and have varying gas permeability rates, liquid impermeable membranes are preferred. The inner membrane 30 is substantially ion-impermeable, hydrophobic and liquid water impermeable. It is composed of a substantially non-reactive microporous material, such as microporous polytetrafluorethylene or copolymers of tetrafluorethylene and hexafluoropropylene in weight ratio of approximately 95:5 to 75:25 (available as Teflon®, a registered trademark of E. I. duPont de Nemours and Co., Inc.), microporous polyvinylchloride, microporous polyvinylfluoride, microporous polyethylene, and microporous polypropylene.
There are qualitative limits to the maximum and minimum allowable values for outer membrane permeability. If permeability is too low, the rate of gas absorption will be below the limit of detection. If permeability is too high, the rate of gas absorption affects the gas concentration outside the membrane, making it sensitive to the rate and direction of air movement. These "windage" effects are precluded when the permeation rate of gas species through the outer membrane is significantly lower than the diffusion rate of the same gas species in air. The permeability of the inner membrane is preferably selected to be at least four times greater than that of the outer membrane. This ensures that it is the permeability of the outer membrane that controls the rate of gas molecule entry into internal electrolyte 20.
The dual membrane system effectively eliminates two experimental difficulties encountered in the use of single membrane chemically integrating dosimeters. The first of these is the deposit of precipitate resulting from the absorption of gas 12 in the electrolyte 20. This deposition causes a change in membrane permeability during exposure. The interposition of the inner membrane 30, which is hydrophobic and ion-impermeable, prevents the precipitate from depositing on the rate controlling outer membrane 10. At the same time, precipitation on the inner protective membrane does not interfere with the operation of the dosimeter as its pores are sufficiently large to preclude any but long term effects on the permeability rate. The second experimental difficulty arises when the internal electrolyte selected to react with the absorbed gas is chemically reactive with the gas permeation membrane. The interposition on the non-reactive inner membrane 30 between electrolyte 20 and the rate controlling membrane 10 overcomes the chemical attack problem.
As used in the claims, the inner membrane 30 is a "protective" membrane in two senses. First, the microporous hydrophobic nature of the inner membrane prevents any changes in the gas permeation rate through the inner membrane due to precipitate formation within the electrolyte 20. This is due to the air-gap nature of these materials which contain very little structure in relation to the volume of holes or gaps. Precipitation that does occur upon entry of the gas into the electrolyte is on the surface of the structure of the inner membrane and not on the gaps, and thus does not effect permeation rate.
The inner membrane is also "protective" in the sense that the inner membrane's liquid impermeable nature prevents the electrolyte 20 from entering the gaps in the membrane and therefore from contacting the outer membrane 10. Chemical reaction (or attack) between the electrolyte 20 and outer membrane 10 is prevented, protecting the gas permeation rate of the outer membrane at both short and long-term intervals. Shelf-life of the dosimeter is extended since no interaction can occur between the gas permeation rate controlling outer membrane and the electrolyte. Regardless of the chemical reaction which occurs within the electrolyte, the permeability of the gas of interest through the outer membrane remains unaffected.
As an example of how the two membrane dosimeter prevents precipitate deposition on the outer membrane 10, the hydrogen sulfide, H 2 S, dosimeter is more fully described. The composition of internal electrolyte 20 is selected to be at a convenient concentration of, for example, 7.0×10 -4 M AgNO 3 in 1 M Na 4 EDTA (ethylene di-nitrilo tetracetate ion), silver complexing agent, adjusted to a pH of 12. Upon permeation of gas species 12 into internal electrolyte 20, the following two reactions occur:
H.sub.2 S (gas)+20H.sup.-⃡ 2H.sub.2 O+S.sup.-2 (1)
2Ag.sup.+ +S.sup.-2 ⃡Ag.sub.2 S precipitate (2)
Exposure to H 2 S is determined by measing the decrease in concentration of Ag + ion resulting from the precipitation of silver sulfide. Upon contacting the electrolyte, H 2 S gas is completely converted to sulfide ion S -2 and bisulfide ion HS - . While some of the precipitate may deposit on the inner protective membrane 30, this action has no adverse effect on the membrane's permeability due to its microporous nature. The decrease in Ag + ion concentration can be monitored by a combination Ag/S electrode, (Model #941600, available from Orion Research Incorporated, Cambridge, Mass.).
The selection of a suitable Ag + ion concentration for internal electrolyte 20 is based on the following equation ##EQU1## where: V g is the volume of absorbed H 2 S at room temperature and pressure, in cubic centimeters,
P is the permeability of the outer membrane,
K is a constant equal to 1×10 9 ,
T is the thickness of the outer membrane in cm.,
t is the absorption time in seconds,
A is the area of the outer membrane in square centimeters,
(H·Δp) is the design partial pressure for H 2 S, where H is the height of mercury at standard pressure in centimeters, and
Δp is the TLV for hydrogen sulfide gas, times 10 -6 .
A silicon rubber polycarbonate copolymer (MEM 213, available from General Electric Co., Schenectady, N.Y.) is selected for the outer membrane. It is 2.54×10 -3 cm thick, 6.0 square centimeters in area, and has a permeability P of 220. The height of mercury is 76.0 cm and the ΔP is 10×10 -6 . For an eight-hour day, absorption time is 2.88×10 4 seconds.
Solving for V g , the volume of H 2 S absorbed in an eight-hour day is determined to be 1.14×10 -2 cm 3 . If a dosimeter with 4 ml of internal solution is used, the concentration of absorbed H 2 S in that 4 ml of solution is 1.27×10 -4 M. Since two Ag + ions are consumed for each H 2 S molecule absorbed in producing Ag 2 S, the silver ion concentration in the internal electrolyte must be at least twice the concentration of absorbed H 2 S, or 2.54×10 -4 M. The method of measurement is subtractive in the sense that a final Ag + ion concentration is subtracted from an initial Ag + ion concentration. Tests with this method indicate that the most precise results are obtained when the final concentration is roughly half that of the initial. For this reason, initial Ag + ion concentration is again doubled to 5.08×10 -4 M. The AgNO 3 concentration of 7.0×10 -4 M is chosen to be slightly greater than this design value.
One of the advantages of the electrolyte utilized for determining H 2 S is that interferences from halogen ions, such as Cl - , and from HCl, can be eliminated by the addition of an appropriate silver complex of such strength that sulfide reacts with silver present in the complex as readily as with free silver ion. Other silver complexing agents which maintain a free silver activity between 10 -6 and 10 -17 may be used in place of Na 4 EDTA. Since silver chloride is relatively much more soluble than silver sulfide, it will not be precipitated in the presence of the complex.
By way of illustration, for silver chloride to precipitate and thereby interfere with H 2 S measurement, the product of the silver ion activity and the chloride ion activity must be greater than the K sp , which is 10 -9 .2.
(Ag.sup.+) (Cl.sup.-)>K.sub.sp (4)
In the presence of EDTA the siliver ion activity is given by equation 5.
(Ag.sup.+) (EDTA) (β)=(R) (5)
where β is the literature value of the stability constant for EDTA which is 10 7 .3, and R is the total silver concentration.
By solving equation (5) for (Ag + ), substituting in equation (4), then solving for (Cl - ), equation (6) is obtained.
(Cl.sup.-)>(K.sub.sp) (EDTA) (β)/R (6)
Tests were conducted near the pK for EDTA, at pH=12.0. Roughly half of the EDTA present is active. For the 7.0×10 -4 AgNO 3 in 1 M Na 4 EDTA solution, the minumum chloride concentration required for precipitation can be determined.
(Cl.sup.-)>24.50/(2)>12.25 M (7)
where 2 is a correction factor for active EDTA. Only at excessively high chloride concentrations will chloride ion interfere. The concentration of active EDTA can be chosen to preclude any anticipated chloride ion interference. Given an anticipated concentration of chloride ion and the above equation, an EDTA concentration can be selected to eliminate any interference. In this case, HCl or Cl 2 at 10 times the ACGIH TLV values of 5 ppm and 3 ppm, respectively, do not interfere.
TABLES I and II illustrate the success of the two-membrane structure over the conventional one-membrane system utilized in the past in maintaining the effective permeability of the outer membrane. A silicon rubber outer membrane and a microporous Teflon® inner membrane were used. Internal electrolyte 20 was a silver complex of 7×10 -4 M AgNO 3 in 1 M Na 4 EDTA (adjusted to pH=12.0). Even at lower levels of H 2 S, TABLE I indicates the Ag 2 S precipitate alters effective permeability of the silicon rubber single membrane to render such a system ineffective. The 10 hour tests show a measured drop of 13.7 ppm from the known supply of 25 ppm of H 2 S. TABLE II shows the increased accuracy resulting from the use of the double membrane structure. "Average H 2 S Concentration" was found to be very close to "Generated H 2 S Concentration".
TABLE I______________________________________SINGLE MEMBRANE DOSIMETERLong Term Exposure to H.sub.2 S No. of AverageTime dosimeters Generated H.sub.2 S Concn.of Run tested H.sub.2 S Concn. found % Error______________________________________10 hrs. 7 25 ppm 11.3 ppm/hr 54.86 hrs. 8 25 ppm 22.3 ppm/hr 10.85 hrs. 6 25 ppm 19.8 ppm/hr 20.84 hrs. 6 25 ppm 25.6 ppm/hr 2.44 hrs. 8 25 ppm 24.0 ppm/hr 4.01 hr. 8 25 ppm 25.0 ppm/hr 0.0______________________________________
TABLE II______________________________________DOUBLE MEMBRANE DOSIMETERLong Term Exposure to H.sub.2 S No. of AverageTime dosimeters Generated H.sub.2 S Concn.of Run tested H.sub.2 S concn. found % Error______________________________________7 hrs. 4 25 ppm 24.7 ppm/hr 1.27 hrs. 4 25 ppm 25.3 ppm/hr 1.27 hrs. 8 25 ppm 25.6 ppm/hr 2.47 hrs. 8 30 ppm 30.0 ppm/hr 0.06 hrs. 5 40 ppm 38.1 ppm/hr 4.8______________________________________
Test results show the reliable determinations of H 2 S in the 5-32 ppm range can be made for durations up to an eight-hour work day. Threshold limit values have been set by the ACGIH in 1976 at 10 ppm for time weighted average and 15 ppm for short term exposure limit. The dosimeter has an observed shelf life of over eight months.
In an analogous dosimeter for hydrogen chloride, HCl, the internal electrolyte 20 is a silver nitrate solution, AgNO 3 . Upon absorption of HCl, silver chloride precipitate is formed according to equation 8. (Ksp=1.8×10 -10 ).
HCl+Ag.sup.+ +NO.sub.3 -⃡AgCl.sub.ppt. +HNO.sub.3 (8)
The decrease in Ag + ion concentration is measured with a silver/sulfide electrode (Model #941600, available from Orion Research Incorporated, Cambridge, Mass.). The interposition of the inner membrane protects the outer diffusion rate controlling membrane from precipitate deposition. A second benefit is that the inner membrane also prevents silver ion from being absorbed into the silicone rubber or polycarbonate copolymer outer membrane, thereby altering the permeability of the outer membrane. As an example of the selection of a suitable silver nitrate, AgNO 3 , concentration, a dual membrane dosimeter having an outer membrane with a permeability constant P of 500, 2.54×10 -3 cm thick, area of 6 square centimeters and 1 ml of internal electrolyte is considered. At the TLV of 5 ppm (7 mg/cubic meter) per eight-hour day, HCl would enter the solution at 1.84×10 -11 moles/second, and the internal solution would be about 5×10 -4 M after eight hours. Since the silver ion concentration must exceed the expected HCl level, a minimum Ag + ion concentration of 10 -3 M would be used.
Similarly, in a dual membrane dosimeter for measuring hydrogen fluoride, HF, the internal electrolyte 20 is a calcium acetate solution, Ca(OAc) 2 . Upon absorption of HF, calcium fluoride precipitate is formed according to equation 9 (K sp =1.8×10 -11 ).
2HF+Ca.sup.+2 +2(OAc).sup.- ⃡CaF.sub.2 ppt.+2HOAc (9)
The decrease in Ca +2 concentration is measured with a calcium electrode (Model #922001, available from Orion Research Incorporated, Cambridge, Mass.). The interposition of the inner protective membrane 30 prevents the deposition of calcium fluoride precipitate on the outer membrane. For a dual membrane dosimeter with an outer membrane 2.54×10 -3 cm thick, an area of 6 square centimeters, an internal electrolyte volume of 1 ml and a permeability constant P of 400, a minimum Ca(OAc) 2 concentration of 2.5×10 -4 M is used to measure HF at the TLV range of 3 ppm for an eight-hour day.
As an example of how the dual membrane dosimeter eliminates chemical attack on the gas permeation membrane, said dosimeter for measuring sulfur dioxide, SO 2 , is more fully described. In the SO 2 dosimeter, the composition of internal electrolyte 20 is conveniently selected to be 1×10 -3 M mercuric bromide (HgBr 2 ) in 5×10 -3 M acetic acid buffer (HOAc/NaOAc) at pH 4.8 with 1% dimethylformamide. Upon permeation of gas species 12 into internal solution 20, the following reactions occur.
SO.sub.2 (gas)+H.sub.2 O⃡2H.sup.+ +SO.sub.3.sup.-2 (10)
HgBr.sub.2 +SO.sub.3.sup.-2 ⃡Hg(SO.sub.3)Br.sup.- +Br.sup.-(11)
Hg(SO.sub.3)Br.sup.- +SO.sub.3.sup.-2 ⃡Hg(SO.sub.3)2.sup.-2 +Br.sup.- (12)
Exposure to SO 2 is determined by measuring the increase in concentration of Br- ion.
Experimentation indicates that in addition to reaction (12) above, the mercuric sulfite-bromide complex also reacts with mercuric bromide in solution to form sulfate ion, SO 4 -2 , mercurous bromide precipitate, and bromide ion, according to equation (13).
Hg(SO.sub.3)Br.sup.-1 +HgBr.sub.2 +H.sub.2 O→SO.sub.4.sup.-2 +Hg.sub.2 Br.sub.2 ppt. +Br.sup.- +2H.sup.+ (13)
Free energy calculations indicate that the above reaction is possible, although the time for complete reaction at room temperature is on the order of one week. Heating the dosimeter at 90° C. for 10-15 minutes completes reaction 13 above and stabilizes the Br- ion concentration. The Br- ion determination can thereafter be made at convenience, since heating does not change the amount of SO 2 absorbed. Accuracy of determination does not depend on the time at which the heating occurs. The increase in Br- ion concentration is measured with a bromide electrode (Model #943500, available from Orion Research Incorporated, Cambridge, Mass.).
The gas permeation membrane is susceptible to chemical attack by the mercuric bromide/acetic acid complex. By interposing the liquid impermeable inner membrane 30 between the outer membrane and the electrolyte attack by the internal electrolyte 20 on the outer membrane 10 is prevented. The selection of a suitable mercuric bromide concentration for internal solution 20 is governed by the analysis already described for H 2 S and shown in equation 3. For the same geometry dosimeter as in the H 2 S case, with a permeability P of 80 and a Δp of 5×10 -6 , the volume of SO 2 absorbed in an eight-hour day is 2.05×10 -3 cm 3 . The concentration of absorbed SO 2 is 1.16×10 -2 M.
One of the added advantages of the electrolyte utilized for SO 2 measurement is that the presence of ammonia, hydrogen chloride, and chlorine, does not interfere. The major interference with SO 2 determinations is H 2 S, which quantitatively forms mercuric sulfide and also liberates bromide. For most applications, however, this is not a problem in that usually only one species or the other is present. Using an internal electrolyte wherein the number of moles of bromide ion is in the range between one and ten times the number of moles of the highest level of SO 2 to be measured, reliable determinations of SO 2 in the 0.5-50 ppm range can be made for durations up to an eight-hour day.
In a dosimeter analogous to the SO 2 dosimeter, ammonia, NH 3 , can be measured using a very dilute mercuric chloride complex as internal electrolyte 20. The mercuric chloride complex is undissociated and is present as a covalent compound with very little free chloride present. In the presence of ammonia a new complex with mercury is formed, and chloride ion, Cl - , is released, according to equation 14. (Stability constant=1.8×10 9 ).
HgCl.sub.2 +4NH.sub.3 ⃡Hg(NH.sub.3).sub.4.sup.+2 +2Cl.sup.-
The increase in Cl - ion concentration is measured with a chloride electrode (Model #941700, available from Orion Research Incorporated, Cambridge, Mass.). Since the outer membrane is susceptible to chemical attack by the mercuric chloride complex and absorption of the complex into said membrane, the interposition of the inner protective membrane insulates the outer membrane from both of these adverse effects. The selection of a suitable mercuric chloride complex concentration is governed by the same analysis shown for H 2 S in equation 3. For the same geometry dosimeter as in the H 2 S case with a permeability P of 1500 and a ΔP of 50×10 -6 , the rate of NH 3 entry is 5.5×10 -10 moles/sec. After 8 hours of exposure the 1 ml internal solution would be about 1.5×10 -2 M NH 3 . Since the ratio of mercuric chloride reacting is one atom of mercury to four molecules of ammonia, a minimum HgCl 2 concentration of 7.5×10 -3 M would be used.
Similarly, in a dual membrane dosimeter for measuring hydrogen cyanide, HCN, the internal electrolyte 20 contains an argentocyanide complex, which dissociates to a small but measurable degree to form silver ion and cyanide ion, as shown in equation 15. Stability constant=1.0×10 21 .
Ag(CN).sub.2.sup.- ⃡Ag.sup.+ +2CN.sup.-. (15)
When hydrogen cyanide gas, HCN, is absorbed by the internal electrolyte, additional CN - ion is provided and equilibrium equation (15) is forced toward the left. The decrease in Ag + ion concentration is measured with a silver/sulfide electrode (Model #941600, available from Orion Research Incorporated, Cambridge, Mass.). Hydrogen cyanide exposure is thereby determined. The argentocyanide complex electrolyte solution 20 is insulated from the outer membrane 10 by inner protective membrane 30, eliminating any chemical attack by the complex on said outer membrane. The argentocyanide complex is used as an indicator only, and a convenient minimum concentration is 10 -4 M Ag + . For a permeability P of 900, Δp=10×10 -6 , an outer membrane thickness of 2.54×10 -3 cm, and 1 ml of internal solution 20, the rate of HCN gas entry is 6.6×10 -11 moles/sec. After eight hours exposure, the concentration of HCN is 1.9×10 -3 M. | A chemically integrating dosimeter for measuring gases, composed of a dual membrane system and an internal electrolyte solution. The outer membrane is a gas permeation rate controlling membrane. The inner membrane is a microporous hydrophobic protective membrane interposed between the electrolyte solution and the outer membrane. The dosimeter makes accurate determinations of time integrated exposures to various gases in the atmosphere and can be conveniently used by workers in industrial environments over a wide range of field conditions. | 8 |
TECHANICAL FIELD
This disclosure relates to fuel-fired water heaters.
BACKGROUND
A commonly used gas-fired water heater is the storage type, generally comprising an assembly of a water tank, a main gas burner to provide heat to the tank, a standing pilot burner to initiate the main burner on demand, an air inlet adjacent the burner near the base of the jacket, an exhaust flue and a jacket to cover these components. Another type of gas-fired water heater is the instantaneous type which has a water flow path through a heat exchanger heated, again, by a main burner initiated from a pilot burner flame. For convenience, the following description is in terms of storage type water heaters. However, the invention is not limited to this type.
A particular difficulty with many locations for water heaters is that they are also used for storage of other equipment such as lawn mowers, trimmers, snow blowers and the like. It is common for such machinery to be refueled in such locations.
There have been a number of reported instances of spilled gasoline and associated fumes being accidentally ignited. There are many available ignition sources, such as refrigerators, running engines, electric motors, electric light switches and the like. However, gas water heaters have sometimes been suspected because they often have a continuously burning pilot flame and combustion air inlets disposed at or near floor level, where spillage may occur.
To contain ignitions that may occur due to the accidental spillage of fuel near a gas fired water heater, many manufacturers have incorporated flame traps into the design of their water heater. An example of such a design is disclosed in U.S. Pat. No. 6,293,230 to Valcic et al. The flame traps used in such designs comprise ports sized and shaped to cause air and extraneous fumes to pass through the ports at a velocity higher than the flame velocity of the extraneous fumes, thereby confining ignition and combustion of the extraneous fume species within the combustion chamber.
One potential problem associated with the ports of the flame arresters is that the ports may become clogged with lint, dust, oil or any other element that may become disposed in or around the ports. When the ports become clogged, there is a potential for the combustion of the burner to burn inefficiently and produce increased levels of CO.
One general consequence to both the emission of CO and the ignition of vapors is that the temperature in the combustion chamber rises above a normal operating level. It would be beneficial to provide a water heater with an improved system for detecting a rise in temperature in the combustion chamber and cut the fuel to the burner, thereby terminating combustion in the combustion chamber.
SUMMARY
We provide fuel-fired water heaters and devices for sensing combustion chambers of fuel-fired water heaters.
One aspect relates to a water heater having a water container; a combustion chamber disposed below the water container and formed at least partially by a shell having an interior surface; a burner disposed within the combustion chamber; a fuel supply line connected to the burner; a valve associated with the fuel supply line; a movable combustion chamber sensor disposed interiorly of the shell proximate to the interior surface of the shell, and adapted to sense a rise in temperature indicative of an abnormality in the combustion chamber; and a switch associated with the sensor and operatively associated with the valve such that the switch triggers the valve to shut off fuel to the burner in response to a sensed temperature by the sensor.
Another aspect relates to a combustion chamber temperature sensing system including a casing having a sensing extension, and a barrel portion; a sensor disposed within the barrel portion and adapted to operate from a concave to convex position upon reaching a predetermined temperature; a switch including a member having a fixed first end portion connected to a first terminal and a movable second end portion biased against a second terminal; and a shaft portion is disposed between the sensor and the member and adapted to move the second end portion away from the second terminal when the sensor shifts from a concave to a convex position.
A further aspect includes a water heater including a water container; a combustion chamber disposed below the water container and formed at least partially by a shell having an interior surface; a burner disposed within the combustion chamber; a fuel supply line connected to the burner; a valve associated with the fuel supply line; a movable combustion chamber sensor disposed interiorly of the shell proximate to the interior surface, and adapted to sense a rise in temperature indicative of a selected amount of carbon monoxide present in the combustion chamber; and a switch associated with the sensor and operatively associated with the valve such that the switch triggers the valve to shut off fuel to the burner in response to a sensed temperature by the sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of illustration, there is shown in the drawings a form which is presently preferred; it being understood, that this disclosure is not limited to the precise arrangements and instrumentalities shown.
FIG. 1 is a side elevational view, taken partly in section, of a gas water heater.
FIG. 2 is a front elevational view, taken partly in section, of the gas water heater shown in FIG. 1 .
FIG. 3 is a front elevational view of selected parts of the lower portion of the gas water heater shown in FIG. 2 .
FIG. 3A is an exploded view of a portion of the structure shown in FIG. 3 .
FIG. 4 is a side view of a fuel supply line assembly with the burner removed for ease of understanding.
FIG. 5 is a top plan view of the assembly shown in FIG. 4 .
FIG. 6 is an exploded side elevational view of a sensing system.
FIG. 7 is a top plan view of a casing portion shown in FIG. 6 .
FIG. 8 is a top plan view of a spacer shown in FIG. 6 .
FIG. 9 is a bottom plan view of a circuit portion shown in FIG. 6 .
FIG. 10 is a cross sectional view of an embodiment of the sensing system of FIG. 6 in an assembled condition.
FIG. 11 is a cross sectional view of the sensing system of FIG. 7 in a closed circuit condition, inserted in an access plate.
FIG. 12 is a cross sectional view of the sensing system of FIG. 8 in an open circuit condition.
DETAILED DESCRIPTION
It will be appreciated that the following description is intended to refer to specific aspects of the disclosure selected for illustration in the drawings and is not intended to define or limit the disclosure, other than in the appended claims.
Turning now to the drawings in general and FIGS. 1 and 2 in particular, the number “2” designates a storage type gas water heater 2 . The water heater 2 includes a jacket 4 which surrounds a water tank 6 , and a main burner 14 in a combustion chamber 15 . Passing through the center of the tank 6 is a flue 10 , which incorporates a series of baffles 12 to better transfer heat generated by the main burner 14 . The water tank 6 is preferably capable of holding heated water at a pressure at or exceeding that of any water main that may feed the water heater 2 . The water tank 6 is preferably insulated by foam insulation 8 . Alternative insulation may include fiberglass or other types of fibrous insulation, as is known to those skilled in the art. Preferably, fiberglass insulation 9 surrounds combustion chamber 15 and the lowermost portion of water tank 6 . It is possible that heat resistant foam insulation can be used if desired. A foam dam 7 separates the foam insulation 8 and the fiberglass insulation 9 .
Located underneath the water tank 6 is the main burner 14 which uses natural gas or other gases such as LPG, for example. Other suitable fuels may be substituted, as is known to those skilled in the art. The main burner 14 combusts a gas and air mixture and the hot products of combustion resulting rise up through flue 10 , possibly with heated air. Preferably, the water tank 6 is lined with a glass coating for corrosion resistance. The bottom portion 5 of the water tank 6 is preferably coated on both its interior facing surface 3 and exterior facing surface 11 . The thickness of the coating of exterior facing surface 11 is preferably about half of the thickness of the coating on the interior facing surface 3 . Also, the lower portion of flue 10 is preferably coated on both of its opposing surfaces. The surface exposed to the flue gases preferably has a thickness about half the thickness of the surface exposed to water in water tank 6 . The glass coating helps to prevent scaling of the flue and water tank surfaces.
Referring now to FIGS. 1-5 , the combustion chamber 15 also contains a pilot burner 49 connected to a gas control valve 48 by a pilot fuel supply line 47 . A sheath 52 , preferably made of copper, containing wires (not shown) from a flame detecting thermocouple 51 to ensure that, in the absence of a flame at the pilot burner 49 , the gas control valve 48 shuts off the gas supply. The thermocouple 51 may be selected from those known in the art. Robertshaw Model No. TS 750U is one preferred thermocouple. The gas control valve 48 supplies fuel to the burner 14 by way of a fuel supply line 21 .
FIGS. 1-5 show the fuel supply line 21 and pilot fuel supply line 47 extending outwardly from a plate 25 . The plate 25 is removably sealable to a skirt 60 that forms the side wall of the combustion chamber 15 . The plate 25 is held into position by a pair of screws 62 or by any other suitable means. The pilot fuel supply line 47 and fuel supply line 21 preferably pass through plate 25 in a substantially fixed and sealed condition. The sheath 52 also extends through the plate 25 in a substantially fixed and sealed condition as does an igniter line 64 . The igniter line 64 connects on one end to an igniter button 22 and on a second end to a piezo igniter 66 (see FIGS. 3 and 5 ). The igniter button 22 can be obtained from Channel Products, for example, however those skilled in the art will recognize that many variations of the igniter button 22 may be used. Each of the pilot fuel supply line 47 , the fuel supply line 21 and the sheath 52 are removably connectable to the gas control valve 48 by compression nuts 68 , 70 and 72 , respectively. Each of the compression nuts 68 , 70 and 72 are threaded and threadingly engage the control valve 48 .
Referring now to FIGS. 1-5 , the products of combustion pass upwards and out the top of the jacket 4 via a flue outlet 16 after heat has been transferred from the products of combustion to water contained in the water tank 6 . The flue outlet 16 discharges conventionally into a draft diverter 17 which in turn connects to an exhaust duct leading outdoors, as is well known to those skilled in the art.
The water heater 2 is preferably mounted on legs 24 . The water heater has a bottom pan 26 , which is raised off of the floor by the legs 24 . The bottom pan 26 preferably has one or more apertures 28 or some other means (not shown) for receiving combustion air, and allowing the combustion air to pass therethrough.
The gas control valve 48 is preferably electronically operated, as is well known to those skilled in the art. Preferably, when power is supplied to the gas control valve 48 , the valve 48 is operable to the open position. Preferably, the valve 48 controls the flow of gas through both the fuel supply line 21 and pilot fuel supply line 47 . Preferably, the valve 48 is connected to a fuel source (not shown) by an external fuel supply line (not shown) as is well known in the art. Power may be provided in mill-volts, generated by a thermocouple. However, those skilled in the art will recognize that the power may come from any suitable source. The power may be measured in milli-volts up to 240 Volts AC.
Preferably, the valve 48 is adapted to close when a source of power to the valve 48 is terminated. Closure of the valve 48 occurs in a manner that is well known. By way of example only, the valve 48 may be biased in the closed position by a spring and opened by an electronic actuator. When power to the electronic actuator is terminated, the spring may force the valve 48 to the closed position.
Referring now to FIGS. 2 , 3 and 5 , a combustion chamber sensing system 100 is shown. The combustion chamber sensing system 100 is shown as being disposed on the plate 25 , although it need not be. For example, it may be disposed on skirt 60 if desired. Preferably, the sensing system 100 may be electronically connected to the valve 48 by a wire 86 . For purposes of describing the sensing system 100 , the terms proximal and distal, respectively, refer to the directions closer to and away from the burner 14 disposed within the combustion chamber 15 .
Referring now to FIGS. 6 to 12 , the system 100 preferably comprises a sensor casing 102 , a sensor 104 , a shaft 106 , a spacer 108 , and a switch portion 110 . The system further comprises a proximal end portion 103 , a distal end portion 105 and a longitudinal axis 101 extending therethrough from the proximal end portion 103 to the distal end portion 105 .
Preferably, the sensor 104 is disposed within the casing 102 . The spacer 108 is disposed distally of the sensor 104 , and the shaft 106 is inserted through a central passageway 148 in the central passageway 148 in the spacer 108 . The switch portion 110 is disposed distally to the spacer 108 , on an opposite side of the spacer 108 from the casing 102 . When the sensing system 100 is disposed through the plate 25 , the casing 102 is the part of the sensing system that is disposed closest to the burner 14 . Correspondingly, the switch portion 110 is the part of the sensing system 100 that is disposed furthest away from the burner 14 . While the sensing system 100 having a casing 102 , sensor 104 , and switch portion 110 is described herein, those skilled in the art will recognize that a variety of other specific structures may be utilized.
The casing 102 , moving from a distal to proximal portion thereof, preferably comprises a barrel portion 120 , a flange portion 122 and a sensing extension portion 124 . The sensing extension 124 extends proximally from the flange portion 122 in a direction away from the barrel portion 120 . Preferably, the barrel portion 120 , is generally cylindrical and hollow. The barrel portion 120 comprises a generally circumferential exterior wall 126 that defines an interior cavity 128 . A proximal end of the interior cavity 128 is further defined by an internal wall 130 . The internal wall 130 is generally perpendicular to the longitudinal axis 101 . A circumferential ridge 132 is disposed within the interior cavity 128 . The circumferential ridge 132 extends substantially circumferentially around the outer edge of the internal wall 130 , along the inner surface of the exterior wall 126 . Preferably, a distal casing lip 166 extends distally and towards the longitudinal axis 101 from the exterior wall 126 . While a circumferential barrel portion 120 is disclosed here, those skilled in the art will recognize that the barrel portion 120 may be any suitable shape.
The flange portion 122 is preferably disposed proximally of the barrel portion 120 . Preferably, the flange portion 122 has a proximal flange wall 134 located on a proximal surface thereof and generally perpendicular to the longitudinal axis 101 . Preferably, an exterior surface 136 of the flange portion 122 is generally hexagonal. The exterior surface 136 is made up of a plurality of exterior flat portions 136 a and exterior corners 136 b . The corners 136 b of the hexagonal exterior surface 136 extend generally farther from the longitudinal axis 101 than the circumferential exterior wall 126 of the barrel portion 120 . While a hexagonal shaped flange portion 122 is shown here, those skilled in the art will recognize that the flange portion 122 may have many different shapes.
Preferably, the sensing extension portion 124 extends proximally from the proximal flange wall 134 along the longitudinal axis 101 . The sensing extension portion 124 comprises a generally elongated post. Preferably, an exterior surface 138 of the sensing extension portion 124 is threaded, although those skilled in the art will recognize that the exterior surface 138 may be smooth or have some other suitable texture without departing from the scope of the invention. One advantage of the threaded exterior surface 138 is that other articles may be connected to the sensing extension 124 with relative ease. Once installed in the water heater 2 , the sensing extension is preferably the closest part of the sensing system 100 to the burner 14 .
The sensor 104 is disposed within the interior cavity 128 and completely inwardly of skirt 60 . The sensor 104 is a generally circular disc. The sensor 104 is preferably a bimetallic snap disc, which is well known in the art. The sensor 104 comprises an outer circumferential portion 140 and a central portion 142 . The sensor 104 is generally biased in a concave position when viewed from the distal direction and convex when viewed from the proximal direction. For purposes of this disclosure, the concave position shall be interchangeably used with the unsnapped position.
Preferably, when the sensor 104 is inserted into the interior cavity 128 , the outer circumferential portion 140 engages the circumferential ridge 132 . The circumferential ridge 132 is raised enough from the internal wall 130 that when the outer circumferential portion 140 engages the circumferential ridge 132 , the central portion 142 does not contact the internal wall 130 . The sensor 104 , while generally biased in a concave position, preferably operates to a convex position upon reaching a predetermined temperature.
The spacer 108 is generally circular, disc shaped, has a central passageway 148 and adapted to partially fit within the internal cavity 128 of the casing portion 102 . Preferably, the spacer 108 is disposed generally perpendicular to the longitudinal axis 101 . The spacer 108 comprises a proximal spacer surface 144 and a distal spacer surface 146 . The spacer 108 comprises a central spacer passageway 148 adapted to allow the shaft 106 to pass therethrough along the longitudinal axis 101 . A distal lip 150 extends distally from the distal spacer surface 146 and away from the skirt 60 toward the jacket 4 . Preferably, the distal lip 150 extends circumferentially around the central spacer passageway 148 . A circumferential reveal 152 is disposed around the outer edge of the distal spacer surface 146 . A proximal lip 154 extends proximally from the proximal spacer surface 144 . Preferably, the proximal lip 154 is disposed circumferentially around the outer edge of the proximal surface 144 . When the sensing system 100 is assembled, the proximal lip 154 engages the circumferential ridge 132 of the casing portion 102 . A proximal ridge 156 is disposed around an inner edge 155 of the proximal lip 154 and the proximal surface 144 .
When the sensor 104 is inserted into the internal cavity 128 and the spacer 108 is placed above or distally of the sensor 104 , the proximal lip 154 surrounds the sensor 104 , thereby restricting lateral movement of the sensor 104 . The proximal ridge 156 does not compressibly engage the sensor 104 so as to restrict movement of the sensor 104 along the longitudinal axis 101 . Rather, the proximal ridge 156 is disposed just distally of the sensor 104 to loosely restrict longitudinal movement of the circumferential portion 140 of the sensor 104 . Those skilled in the art will recognize that the proximal ridge 156 may compressibly engage the sensor 104 , thereby pressing the sensor 104 against the circumferential ridge 132 of the casing portion 102 . Preferably, the proximal ridge 156 is disposed proximally enough away from the proximal surface 144 of the spacer 108 that when the sensor 104 operates from a concave position to a convex position, the central portion 142 of the sensor 104 does not come into contact with the proximal surface 144 of the spacer 108 .
The shaft portion 106 is preferably a generally elongated solid cylindrical piece. The shaft portion 106 comprises a proximal shaft end portion 106 a and a distal shaft end portion 106 b. The shaft 106 is preferably adapted to pass through the central passageway 148 . Those skilled in the art will recognize that although the shaft 106 and central passageway 148 are shown here having a generally cylindrical profile, any profile shape may be used.
Preferably, during assembly of the sensing system 100 , the shaft 106 is inserted through the central passageway 148 , engaging the central portion 142 of the sensor 104 . The shaft 106 is preferably slidable through the central passageway 148 without much, if any frictional resistance.
The switch portion 110 comprises a generally cylindrical switch casing 158 , having a proximal end 160 comprising a proximal lip 162 . The proximal lip 162 extends circumferentially around the proximal end 160 of the switch casing 158 . Preferably, the outer diameter of the proximal lip 162 is slightly smaller than the inner diameter of the exterior wall 126 of the barrel portion 120 . Preferably, the inner diameter of the proximal lip 162 is larger than the outer diameter of the distal spacer surface 146 , thereby allowing the proximal lip 162 to contact the distal surface of the circumferential reveal 152 while surrounding the distal spacer surface 146 . A distal edge 164 of the proximal lip 162 defines the distal terminus of the proximal lip 162 . The distal edge 164 of the proximal lip 162 is disposed proximally enough along the switch casing 158 that, when the switch portion 110 is inserted into the internal cavity 128 of the casing portion 102 , the distal casing lip 166 exterior wall 126 extends distally of the distal edge 164 of the proximal lip 162 .
Inside of the switch portion 110 is a circuit comprised of a first lead 168 , operatively connected to a first terminal 170 . The first terminal 170 is disposed within the switch casing 158 . The first terminal 170 is conductively and fixedly connected to a conductive member 172 that has a fixed portion and a flexible, movable portion. The conductive member 172 preferably comprises a fixed first contact end 174 , a movable second contact end 176 and a “U” shaped spring section 178 disposed between the fixed first contact end 174 and the movable second contact end 176 . The conductive member 172 is connected to the first terminal 170 at the first contact end 174 .
A second lead 180 is operatively connected to a fixed second terminal 182 . The movable second contact end 176 is biased towards the fixed second terminal 182 by the “U” shaped spring section 178 . When the movable second contact end 176 contacts the fixed second terminal 182 , there is a continuous electrical connection between the first lead 168 and the second lead 180 . In such an instance, there is a closed circuit between the first lead 168 and the second lead 180 . The movable second contact end 176 is operable away from the second terminal 182 by applying force to the movable second contact end 176 distally, thereby compressing the “U” shaped spring section 178 .
As shown in FIG. 10 , when the sensing system 100 is assembled, the distal shaft end 106 b is disposed just below the second contact end 176 . A raised convex contact surface 184 is disposed on the proximal surface of the movable second contact end 176 . The raised convex contact surface 184 is adapted to contact the distal shaft end 106 b in the event that the shaft 106 is translated in a distal direction, towards the conductive member 172 . When the shaft 106 is translated in a distal direction, the distal shaft end 106 b contacts the raised convex contact surface 184 . In other words, convex contact surface 184 moves relative to the balance of switch portion 110 substantially in concert with the movability of shaft 106 . If the shaft 106 is translated further distally, the second contact end 176 is translated distally and away from the fixed second terminal 182 . Thus, movable contact end 176 also moves relative to the balance of switch portion 110 substantially in concert with shaft 106 . When the movable second contact end 176 is translated away from the fixed second terminal 182 , the conductive connection between the first lead 168 and the second lead 180 is broken, thereby rendering the switch portion 110 open, as best seen in FIG. 12 .
It is preferable that the casing portion 102 be constructed from brass, or some other metal with similar heat conducting properties. The sensor 104 is made from materials known to those skilled in the art for bimetallic snap discs. The spacer 108 and the shaft 106 are preferably constructed from ceramic material. The switch portion 110 preferably comprises a combination of materials, each adapted to serve a specific purpose. By way of example, it is preferable that the leads 168 , 180 the terminals 170 , 182 and the flexible conductive member 172 conduct electricity. Preferably, the switch casing 158 and the reset shaft 186 are made from materials that generally insulate against conducting electricity and do not facilitate the flow of electricity therethrough, such as ceramic.
In assembly, as best seen in FIG. 10 , where the bottom of the figure is the proximal direction and the top of the figure is the distal direction, the sensor 104 is first inserted into the interior cavity 128 of the casing portion 102 . The sensor 104 is inserted 104 in a concave position, when viewed from the top or distal direction. This results in the central portion 142 of the sensor 104 being disposed closer to the interior wall 130 than the circumferential portion 140 .
The spacer 108 is inserted into the interior cavity 128 , above the spacer 104 , so that the proximal lip 154 of the spacer engages the circumferential ridge 132 of the casing portion 102 . When the proximal lip 154 of the spacer engages the circumferential ridge 132 of the casing portion 102 , the sensor 104 is disposed between the casing portion 102 and the spacer 108 . There should be sufficient space between the casing portion 102 and the spacer 108 to allow the sensor 104 to operate between concave and convex dispositions.
The shaft 106 is inserted through the central passageway 148 so that the proximal shaft end 106 a engages the distal side of the central portion 142 of the sensor 104 . When the proximal shaft end 106 a engages the distal side of the central portion 142 of the sensor 104 , the proximal shaft end 106 b extends proximally from the distal lip 150 of the spacer 108 .
The proximal lip 162 of switch portion 110 is then inserted into the internal cavity 128 of the barrel portion 120 . The switch portion 110 is inserted far enough into the internal cavity 128 that the distal edge 164 of the proximal lip 162 is proximal of the distal casing lip 166 . During assembly, the distal casing lip 166 is rolled towards the longitudinal axis 101 , thereby retaining the switch portion 110 partially within the casing portion 102 . The switch portion 110 is further partially retained within the casing portion 102 by sizing the pieces so that a press fit exists between the outer circumferential surface of the proximal lip 162 and the inner surface of the exterior wall 126 of the barrel portion 120 .
A movable reset shaft 186 extends through the switch portion 110 along the longitudinal axis 101 . A proximal end 188 of the reset shaft 186 is adapted to engage a distal surface 177 of the movable second circuit end 176 . Thus, the reset shaft moves relative to the balance of switch portion 110 substantially in concert with shaft 106 , convex contact surface 184 and movable contact end 176 . A distal end 190 if the reset shaft 186 extends distally beyond a distal surface 111 of the circuit portion 110 .
When the sensing system 100 is assembled, and the sensor 104 is in a concave position when viewed from the distal direction, it is preferable that the movable second contact end 176 is in contact with the fixed second terminal 182 . It is preferable that the shaft 106 is disposed between the distal surface of the central portion 142 of the sensor 104 and the raised convex contact surface 184 , without engaging the raised convex contact surface 184 at all, or alternatively, without applying enough force the raised convex contact surface 184 to move the movable second circuit end 176 away from the fixed second terminal 182 .
Preferably, the assembled system 100 is installed into the access plate 25 by inserting the system 100 , distal end 105 first, through an aperture in the plate 25 . The system 100 is preferably inserted from an interior side of the plate 25 , when the plate 25 is installed on the water heater 2 . The installation of the system 100 into the plate may be done before the plate 25 is installed onto the water heater 2 . Referring to FIG. 3A , a die contacts plate 25 to punch a hole for system 100 and forms tabs 200 that extend outwardly from plate 25 . The system 100 is then placed into plate 25 through the newly formed hole from the interior. A press then contacts tabs 200 and forms them over the round cap portion 202 of switch portion 110 .
Referring now to FIGS. 11 and 12 , the system 100 is inserted through the plate 25 only far enough that the switch portion 110 extends through the plate 25 . Preferably all, or at least a portion, of the barrel portion 120 is disposed either within the aperture of the plate 25 or on the interior (proximal) side of the plate 25 . There is a space between the distal side of the flange portion 122 and a proximal face 25 a of the plate 25 . A spacer 190 may be disposed between the flange portion 122 and the plate 25 to restrict the distal movement of the sensing assembly 100 . The switch portion 110 is preferably disposed entirely outside of the plate 25 , although those skilled in the art will recognize that all or a portion of the switch portion 110 may be disposed within plate 25 or the combustion chamber 15 .
The sensing assembly 100 may be retained in place, in relation to the plate 25 by a slip ring fastener 192 , or push nut fastener, as is known to those skilled in the art. The fastener 192 preferably compressibly engages the circuit casing 158 , applying inward and distal force on the sensing assembly 100 . Preferably, the fastener 192 biases the sensing system distally, so that the flange 122 compressibly engages the spacer 190 against the proximal face 25 a of the plate 25 . Various alternative methods of mounting the system 100 to the plate 25 are possible. By way of example, a portion of the casing 158 or the exterior wall 126 of the barrel portion 120 may be threaded. Correspondingly, mating threads (not shown) may be disposed on the plate 25 . Additionally, the assembly 100 and a corresponding recess (not shown) in the plate 25 may be shaped to create a mechanical engagement, such as a quarter-turn lock, between the assembly and the plate. The assembly 100 may also be retained in relation to the plate 25 through the use of “C” or “E” clips, or through spot welding a portion of the assembly to the plate 25 . Alternatively, there may be at least one, and preferably two, holes in the switch portion 110 and corresponding hole(s) in the plate 25 . The assembly 100 may be retained to the plate 25 using a stud or other well known fasteners.
Because the barrel portion 120 is disposed within the plate 25 or proximally of the plate 25 , the sensor 104 is mounted interiorly of the plate 25 . The sensor 104 is disposed at a point along the longitudinal axis 101 that is generally even with the distal edge of the flange 122 . This disposition ensures that the sensor 104 is disposed interiorly of the plate 25 . The distance between the proximal face 25 a of the plate 25 and the sensor 104 is large enough that even when the sensor 104 is operated from a concave to a convex disposition, the entirety of the sensor 104 is disposed interiorly of the plate 25 .
In operation, the switch portion 110 is connected in series to a power source on one end and the valve 48 on the other end. Generally, since the switch portion 110 is normally disposed in the closed position, the switch portion 110 facilitates the flow of electrical current from the power source to the gas control valve 48 . The valve 48 is adapted to close when power is interrupted via the opening of the circuit. When the valve 48 closes, the flow of fuel to the burner 14 is stopped.
Generally, combustion occurs in the combustion chamber 15 at a predetermined temperature. This temperature is set according to ways known to those skilled in the art. Those skilled in the art will also recognize that certain events may cause the temperature in the combustion chamber 15 to rise above the predetermined level. Such a rise in combustion chamber 15 temperature may be indicative of a change in the operating characteristics in the combustion chamber 15 such as a flammable vapor event, or the accumulation of the combustion air intake area with lint, dust, oil or other debris, thereby causing the burner 14 to burn in an inefficient fuel-rich condition. When the inefficient, fuel-rich combustion occurs, undesirable levels of carbon monoxide may be released. There may also be other undesirable conditions indicated by an elevated temperature in the combustion chamber 15 as is known to those skilled in the art.
The casing portion 102 is the part of the sensor system 100 that is disposed closest to the burner 14 . Therefore, the casing portion is directly exposed to the heat of the combustion chamber 15 . Heat is conducted through the casing portion 102 to the interior cavity 128 . The sensor 104 senses the temperature of the interior cavity 128 . By sensing the temperature of the interior cavity 128 , the sensor 104 senses the temperature of the combustion chamber 15 .
When the sensor 104 reaches a predetermined temperature, the sensor 104 operates from a concave position, as shown in FIG. 11 , to a convex position, as shown in FIG. 12 . When the sensor 104 operates from concave to convex, the distal movement of the central portion 142 of the sensor 104 translates the shaft 106 distally such that the shaft 106 does not extend or project into combustion chamber 15 at all, thereby translating the movable second circuit end 176 distally and away from the fixed second terminal 182 . Generally, for natural gas models, the predetermined temperature at which the sensor 104 operates from a concave to a convex disposition is in the range between 400 and 460 degrees Fahrenheit. A preferred embodiment of a sensor 104 is adapted to operate from a concave to a convex disposition at 450 degrees Fahrenheit. For models using propane as a fuel, it is preferable to have the predetermined temperature between 300 and 350 degrees Fahrenheit. Those skilled in the art will recognize that the predetermined temperature at which the sensor 104 operates from a concave to a convex disposition may vary outside of the above-mentioned range.
When the movable second circuit end 176 is moved away from the fixed second terminal 182 , the circuit is opened and current no longer flows through the switch portion 110 from the first lead 168 to the second lead 180 . This interruption in the flow of current through the switch portion 110 to the valve 48 triggers the valve 48 to close and restrict the flow of fuel to the burner 14 . The closing of the valve 48 when power is terminated thereto is a procedure that is well known to those skilled in the art.
Preferably, when the circuit is opened, and power to the gas control valve 48 is terminated, gas is no longer permitted to flow to the burner. When gas ceases to flow to the burner 14 , combustion in the combustion chamber 15 is stopped.
The sensing system may be reset by pushing the reset shaft 186 proximally. When pushed proximally, the reset shaft 186 engages the movable second circuit end 176 , which engages the shaft 106 , which engages the sensor 104 . When a user applies proximal force to the reset shaft 186 , the above-described chain of engagement ultimately applies force to the central portion 142 of the sensor 104 and “flip” the sensor 104 from a convex disposition back to a concave disposition.
A variety of modifications to the aspects described will be apparent to those skilled in the art from the disclosure provided herein. Thus, aspects of the invention may be embodied in other specific forms without departing from the spirit or attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of our disclosure. | A combustion chamber is disposed below the water container of a water heater and formed at least partially by a shell. A burner disposed within the combustion chamber and a fuel supply line is connected to the burner. A valve associated with the fuel supply line. A combustion chamber sensor is disposed within the combustion chamber and adapted to sense a rise in temperature indicative of an abnormality in the combustion chamber. A circuit connected to the sensor and the valve such that the circuit triggers the valve to shut off fuel to the burner in response to a sensed temperature by the sensor. | 5 |
This is a Continuation application of application Ser. No. 08/124,938, filed Sep. 21, 1993 now U.S. Pat. No. 5,473,620.
FIELD OF THE INVENTION
This invention relates generally to digital data communication systems, particularly to the encoding and decoding of error correcting codes.
BACKGROUND OF THE INVENTION
In a digital data communication system (including storage and retrieval from optical or magnetic media) in order to increase the transfer rate of information and at the same time make the error rate arbitrarily low, it is necessary to employ an error control system. For fixed signal-to-noise ratios and fixed bandwidths, improvements can be made through the use of error-correcting codes.
With error-correction coding the data to be transmitted or stored is mathematically processed to obtain additional data symbols called check symbols or redundancy symbols. The data and check symbols together make up a codeword. After transmission or retrieval the codeword is mathematically processed to obtain error syndromes which contain information about locations and values of errors.
For many error-correcting codes (e.g. polynomial codes such as, but not limited to, Reed-Solomon codes) the codewords are formed by appending a remainder polynomial (redundancy symbols) to a data polynomial so as to make the composite polynomial divisible by a generator polynomial. The remainder polynomial is obtained by dividing the data polynomial by the generator polynomial and keeping the remainder polynomial. The error syndromes are obtained by dividing the received polynomial (a codeword polynomial which may have an error polynomial added to it) by the individual factors of the generator polynomial.
PRIOR ART
FIG. 1 shows a circuit which can generate redundancy symbols by performing polynomial division.
FIG. 2 shows a plurality of first-order dividers in which each can generate one of the error syndromes.
Prior Art Limitations
One problem arising in the use of these codes is the significant amount of circuitry needed in high-speed implementations of high-order (capable of correcting many errors) generators for the redundancy symbols and the error syndromes. For systems which require the ability to do both the encoding and decoding, albeit not simultaneously, it is a desirable trait to have one circuit capable of generating both sets of symbols. It is also a desirable trait for the encoder to be programmable so as to be able to produce different order codes (codewords with different numbers of redundancy bytes). The usual method has neither of these traits.
U.S. Pat. No. 4,777,635 entitled "REED-SOLOMON CODE ENCODER and SYNDROME GENERATOR CIRCUIT" issued to Neal Glover discloses a circuit which can generate both redundancy and syndrome symbols but is not order-programmable.
The Berlekamp-Welch algorithm is a general decoding algorithm which does not use syndromes but instead uses the encoder circuit to compute a remainder from the received polynomial. However the algorithm is a bit more complicated than that which processes syndromes and it is not order-programmable. It is also possible to convert the remainder to syndromes but this requires significant additional circuitry.
SUMMARY OF THE INVENTION
It is an object of the present invention to decrease the size of the circuitry in a hardware implementation of an error correcting encoder/decoder by using a single circuit to generate check symbols during the transmit operation and to also generate syndromes during a receive operation.
Another object is to decrease the size of the circuitry in a hardware implementation of an error correcting encoder/decoder by using a single circuit to generate check symbols for codewords containing differing numbers of check symbols.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the prior-art solution for generating redundancy symbols.
FIG. 2 shows the prior-art solution for generating syndromes.
FIG. 3 illustrates the basic principle utilized in the present invention.
FIG. 4 shows a block diagram of the preferred embodiment of the present invention.
FIG. 5 shows a block diagram of an alternate embodiment of the present invention.
FIG. 6 shows a block diagram of a further alternate embodiment of the present invention.
FIG. 7 shows a block diagram of a still further alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
This invention includes a method and apparatus capable of generating redundancy symbols and syndromes and is order-programmable. The theory of operation of this invention is as follows: Polynomial codes consist of codewords which are multiples of a generator polynomial. A codeword, c(x), is formed by dividing a data polynomial, D(x), of degree less than k by a generator polynomial, g(x) of degree n-k to obtain a redundancy polynomial, r(x), of degree less than n-k. Appending r(x) to D(x) yields c(x) of degree less than n (i.e. there are k data symbols and n-k redundancy symbols and n total symbols, each symbol having a predetermined plurality of bits m). ##EQU1##
The following explanation will show that it is possible to feed D(x) into a cascade of first-order dividers (where each divider divides by one factor, (x+r j )) to generate r(x). These first order dividers can then be used to generate syndromes during read-operations (decoding).
FIG. 3 shows a cascade of first-order polynomial dividers followed by a cascade of first-order polynomial multipliers. Each polynomial divider is made of a register 200 j a constant multiplier 201 j and adder 202 j each one symbol wide where again, j ranges from 0 to n-k-1. The output of each polynomial divider is the input polynomial multiplied by x and divided by (x+r j ). Each polynomial multiplier is made of a register 210 j , a constant multiplier 211 j and an adder 212 j , and multiplies its input by (x+r j ). At each step of operation (simultaneous clocking of all registers and inputting a further symbol) the output of each divider matches the input to the corresponding multiplier, e.g. 203 0 matches 213 1 . Also each divider register matches the corresponding multiplier register, e.g. A j matches B j . The output of divider cascade 203 n-k-1 is: ##EQU2##
The output of the multiplier cascade is q(x) g(x). The first k terms (symbols) appearing on 203 n-k-1 is q(x) and the first k terms (symbols) appearing on 213 0 is D(x). To obtain the rest of q(x) g(x), the input to the multiplier cascade is set to zero by the gate 214 and the circuit is clocked n-k more times. During these clocks the output of the multiplier cascade, 213 0 , is x n-k D(x) mod g(x), which is the series of redundancy symbols in a polynomial code.
Implementation
Since the multiplier registers in FIG. 3 always match the divider registers, the multiplier cascade can be discarded and during the last n-k clocks the divider can be connected as a multiplier cascade to yield the redundancy symbol S. This is illustrated in FIG. 4. Then when REDUNDANCY TIME is OFF the MUXes 102 and 103 cause the registers 100 and constant multipliers 104 to be connected so as to form a cascade of dividers from left to right (the adders 106 add from left to right). When REDUNDANCY TIME is ON the MUXes 102 and 103 cause the registers 100 and constant multipliers 104 to be connected so as to form a cascade of multipliers from right to left (the adders add from right to left). The function of the MUXes 101 is to form separate dividers (not in a cascade) for syndrome generation.
During a write-operation (encoding) WRITE MODE is ON. For the first k clock times REDUNDANCY TIME is OFF and the input data bytes are passed through to the output of MUX 105. For the last n-k clock times REDUNDANCY TIME is ON and the redundancy symbols are present at the output of MUX 105.
During a read-operation WRITE MODE is OFF and REDUNDANCY TIME is OFF and the entire received polynomial consisting of data and redundancy is input for n clock times. During the last clock time the syndromes are available on the output of MUXes 103.
By holding the reset input to a register ON during redundancy generation the corresponding root for that register is left out of the redundancy computation. This allows the selection of roots to be entirely programmable, and in particular it allows the number of roots (code order) to be programmable.
The generator shown in FIG. 4 is for a Reed-Solomon code (i.e. the roots as shown in the constant multipliers 104 are consecutive powers of alpha, a primitive root of the field). However the invention applies to any polynomial code with any selection of roots. The resets to the registers 100 are "ORDER<j", which is the selection criterion for Reed-Solomon codes (i.e. ORDER consecutive roots are included and the remainder are left out, where ORDER is the number of roots in the generator). However any selection criterion may be used.
FIG. 5 shows an alternate implementation in which one set of MUXes is removed from the adder chain of FIG. 4 and a second adder chain is added. The upper adder chain 306 only adds from left to right (for data time) and the lower adder chain 302 only adds from right to left (for redundancy time). This allows faster operation at the expense of more gates (trading MUXes for adders). MUXes 303 switch between having a divider cascade for data time or having a multiplier cascade for redundancy time. MUXes 301 switch between having a cascade of dividers/multipliers for encoding and having separate dividers for syndrome generation.
FIG. 6 shows an alternate implementation in which the set of MUXes is removed from the upper adder chain in FIG. 5 and its function of allowing syndrome generation is performed by including the set of adders 401 and MUX 407. The lower adder chain 402 and MUXes 403 remain the same as the lower adder chain 302 and MUXes 303 of FIG. 5. During read mode, MUX 407 allows read data to be the input and adder chain 401 is enabled which causes the register REG output for each stage to be added to the next stage twice through adders 401 and 406. This effectively decouples each stage, since in the finite field of GF(2 m ), adding an element to itself results in zero. This allows for the fastest operation, at the expense of more gates (trading MUXes for adders), as the adder chain 406 no longer contains any MUXes.
FIG. 7 shows an alternate implementation in which the MUXes in FIG. 6 have been eliminated. The sections remain in the divider configuration during redundancy time but the input switches from data to redundancy through MUXes 505 and 507. Because of the cancellation that occurs when elements are added to themselves, adding the output of the lower adder chain, which is equal to the sum of the contents of the registers REG, to the input of the upper adder chain, has the same function and result as actually changing the configuration from left-to-right dividers to right-to-left multipliers as in the other implementations.
While the preferred embodiment and various alternative embodiments of the invention have been disclosed and described in detail herein, it will be obvious to those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope thereof. | An apparatus and method of generating redundancy symbols and syndromes which is order-programmable is disclosed. The apparatus and method involves the implementation of an error correcting encoder/decoder for polynomial codes which uses a single circuit to generate check symbols during the transmit operation and to generate syndromes during a receive operation. The selection of roots for the code generator, and hence, the code order is programmable. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit of U.S. provisional application No. 60/603,091, filed on Aug. 20, 2004.
FIELD OF THE INVENTION
[0002] The present invention is directed to unitized fibrous constructs for reinforcing castable mixtures, such as cementitious matrices or mixtures and, more particularly a unitized fibrous construct in which the circumferential retaining element that retains a bundle of reinforcing fibers or filaments also serves as a reinforcing element upon mixture into the castable mixture.
BACKGROUND OF THE INVENTION
[0003] Many proposals have been made to reinforce, strengthen, and/or reduce cracking during curing or otherwise beneficially alter the properties of castable mixtures, such as cementitious mixtures, by applying and/or incorporating various types of fibrous components, including asbestos, glass, steel, as well as synthetic polymer fibers to aqueous based concrete mixes prior to the curing of the concrete. The types of polymer fibers in use or proposed for use include those composed of natural and synthetic composition. As is evident in the prior art, individual fibrous components are well known in terms of their performance modifying attributes. Relatively large diameter fibers, for example, in excess of 40 to 60 microns in diameter, can be added to a cementitious mixture such as a wet concrete blend, dispersed in the blend by mechanical agitation, followed by pouring and curing of the concrete. Large diameter fibers serve to reinforce the concrete after it has been cured, by providing additional tensile strength and minimizing impact damage and crack propagation. Small diameter fibers, typically less than 30 to 40 microns in diameter, and having a relatively high surface area, are commonly added to concrete mixes in order to reduce the development of small elastic shrinkage cracks in the concrete during the curing period. The problem of crack development is known to occur as a result of uneven curing of the concrete. The fibrous components used typically in the practice of reinforcing cementitious mixtures include specifically thermoplastic synthetic fibers of finite staple length, such as polypropylene staple fibers.
[0004] Due to the variable and unpredictable form conventional reinforcing fibrous components have heretofore been provided for end-use consumption, such as at a construction work-site, the accurate and reproducible dosing of reinforcing fibrous component into sequential batches of cementitious mixtures has been dubious at best. Further complicating the actual utilization of the reinforcing fibrous components, numerous synthetic thermoplastic polymers used in the formation of suitable staple fibers are inherently hydrophobic in nature. As a result, difficulties can arise in obtaining a uniform dispersion and blending of the reinforcing fibrous component throughout hydrous cementitious mixtures using conventional mixing equipment.
[0005] Prior attempts to address the issue described have focused on the use of binding agents. U.S. Pat. No. 5,399,195, entitled, “Fibres and material comprising the same”, issued on Mar. 21, 1995, in the name of inventors Hansen et al., discloses the addition of small amounts of fine (less than 30 microns) polymer fibers to concrete. During production, the filaments are treated with a topical wetting agent. After the filaments are chopped into staple-length fibers, the wetting agent holds or binds the staple fibers together in the form of micro-bundles. The micro-bundles remain relatively stable during handling, and when the fibers are added to the concrete mix, the wetting agent promotes dispersion of the fibers. U.S. Pat. No. 6,258,159, entitled, “Product and method for incorporating synthetic polymer fibers into cement mixtures”, issued on Jul. 10, 2001, in the name of inventor Pyle, attempts to address the forming of micro-bundles of fibers by incorporation of binding agents into the staple fibers themselves during the melt-extrusion process.
[0006] The use of binding agents, whether internal or externally applied, while improving in-part issues inherent of individual staple fibers, such practices have not obviated such problems as random agglomerate size, and further, the use of binding agents has introduced additional problems. Most notably, the corresponding performance of the binding agent is based upon application of the binding agent to the reinforcement fibrous components such that the binding agent is both uniformly applied to the majority of the fibers so as to obtain equivalency within the batch, and that no excess binding agent is introduced as such will adversely effect the ability of the reinforcement fibrous components to disengage and distribute homogeneously. One other determent encountered in the use of binding agents is that air is often entrained within the micro-bundles upon application and agglomeration of the staple fibers. When such micro-bundles are subjected to mechanical mixing, the entrained air is released as a foam, which reasonably compromises the ability of the cementitious mixture to cure uniformly.
[0007] Cellulosic tapes have also been utilized to retain reinforcement fibers; however, such tapes can become problematic for a cementitious matrix or mixture as well. See for example U.S. Pat. No. 5,807,458, entitled, “Reinforcing Elements for Castable Compositions”, issued Sep. 15, 1998, in the name of inventors Sanders et al. The cellulose tape is prone to degradation in the alkaline environment of the mixture. Degradation of the tapes may introduce void spaces within the mixture which can negatively impact uniform curing of the cement. Further, the wet cellulose tapes can promote mold growth within the mixture that can lead to cracks in the setting mix.
[0008] More recently, circumferential binding elements have been utilized to provide temporary retention of fibrous constructs, as disclosed in commonly assigned U.S. Patent Publication 2004/0244653, entitled “Unitized Fibrous Concrete Reinforcement”, filed on Dec. 9, 2004, in the name of inventors Schmidt et al, which is herein incorporated by reference as if set forth fully herein. Heretofore, the circumferential binding element was purposeful as a retaining element, but did not contribute incremental functionality within the cementitious matrix.
[0009] As is evident in the industry, an unmet need exists for a means of introducing reinforcing fibrous components into a cementitious mixture such that the reinforcing fibrous components exhibit the attributes of uniform and predictable presentation for use, while the circumferential retaining elements, which temporarily bind the oriented fibrous components, further provide an advantageous and incremental performance within the cementitious matrix.
SUMMARY OF THE INVENTION
[0010] The present invention is directed to unitized fibrous constructs for reinforcement in a castable compound, such as a cementitious matrices or mixtures. The invention provides for a construct that includes a bundle of reinforcing fibers or filaments surround, at least partially, by a retaining element, which also serves the dual purpose, upon addition to the cementitious mixture, of acting as a reinforcing element. In this regard, the retaining element does not need to dissolve or otherwise be dispersible upon addition to the cementitious mixture. As such, degradation issues with dispersible materials are eliminated, such as issues related to void spaces in the mixture and possible mold issues leading to crack propagation. In addition, by creating a construct in which the retaining element serves as a reinforcing element further strengthening and stability of the overall cementitious mixture is imparted from a single unitized fibrous construct.
[0011] In one embodiment of the invention a unitized fibrous construct for reinforcing a cementitious mixture includes a plurality of reinforcing filaments or fibers oriented in a generally parallel relationship such that the plurality of reinforcing filaments or fibers form a unit having a circumferential exterior surface. The unit will those typically form the geometry of a cylindrical bundle of filaments or fibers, although other geometries of the unit are herein contemplated and within the bounds of the present invention. The construct also includes a retaining element that serves as a reinforcing element in the cementitious mixture. The retaining element surrounds at least a portion of the circumferential exterior surface and retains the plurality of reinforcing filaments or fibers prior to adding the construct to the cementitious mixture. Thus, once the construct is formed, the circumferential retaining element aids in maintaining the integrity of the unitized fibrous construct, and the fibrous component therein, for purposes of shipment, measurement, and dosing into a cementitious mixture. Typically the retaining element will be spirally wound around the plurality of fibers or filaments, such that the retaining element provides temporal retention of the bundle of fibers or filaments prior to immersion in the cementitious mixture. In most instances, minimal spiral winding is required, less than about 30% coverage of the surface area of the circumferential exterior surface of the unit, so as to insure that the fibers and filaments become free from containment upon agitation in the cementitious mixture. Upon mechanical agitation of the unitized fibrous construct in a cementitious mixture, the circumferential retaining element is disrupted, allowing for the homogenous release, distribution, and dispersion of the reinforcing filaments and fibers into the overall cementitious mixture and release of the circumferential retaining element itself into the mixture, which also serves as a reinforcing element.
[0012] Typically, the retaining element will be formed of a similar material, and in some embodiments the identical material, as is used to form the reinforcing fibers or filaments. The circumferential retaining element may be selected from suitable materials that are considered structurally beneficial to a cementitious matrix by providing additional reinforcement, minimize impact damage, and crack propagation. Such fibrous or filamentary material at least partially or may entirely include super absorbent polymers, splittable fiber or filaments, and fiber or filaments with three-dimensionality, such as coiled or crimped. Further, such materials may consist of thermoplastic, thermoset and partially soluble resins, which are subject to mechanical failure when a corresponding stress and/or solvency threshold is exceeded. The material selected may also be mechanically modified, as exemplified by fibrillation, drawing, perforation, crimping, embossing or molding, so as to exhibit performance attributes in the cementitious matrix such as a reinforcement or elastic shrinkage crack reduction.
[0013] Various geometries may be employed in the application of the circumferential retaining element, including without limitation, continuous or discontinuous filaments, ribbons, or sheets, which circumscribe the combined, essentially parallel reinforcing fibrous components. It is within the purview of the present invention that the composition of the circumferential retaining elements and of one or more of the reinforcing fibrous components need not necessarily be the same.
[0014] It is further within the purview of the present invention that the retaining element may be placed under additional tension by means of twisting the retaining element. Placing additional tension on the retaining element facilitates the mechanical removal of the retaining element upon mechanical agitation, which then enhances the fiber distribution within a cementitious mixture.
[0015] It is also noted that while the present embodiment includes a single retaining element it is possible, and within the inventive concepts herein disclosed, for more than one retaining element to be used in connection with a single unitized reinforcing construct. For example, two reinforcing elements may be spirally wound around the unit of fibers or filaments in a double-helix type arrangement.
[0016] The reinforcing filaments are continuous filaments and in fiber embodiments the fibers are finite staple-length fibers. Additionally, the reinforcing filaments may be characterized as fibrillated reinforcing filaments. The reinforcing filaments or fibers may be imparted with tension during processing to insure that the degree of dispersion necessary occurs once the bundle of filaments or fibers are free from retention within the cementitious mixture. In alternate embodiments the reinforcing filaments or fibers may be splittable filaments or fibers or may be formed from a super absorbent polymer composition.
[0017] In another embodiment the unitized fibrous construct for reinforcing a cementitious mixture includes a plurality of reinforcing filaments or fibers oriented in a generally parallel relationship such that the plurality of reinforcing filaments or fibers form a unit having a circumferential exterior surface. The construct also includes a retaining element formed of one or more splittable filaments that surround at least a portion of the circumferential exterior surface and retains the plurality of reinforcing filaments or fibers prior to adding the construct to the cementitious mixture. Typically, the splittable filaments will provide reinforcing capabilities once they have been added to the cementitious mixture
[0018] The reinforcing filaments or fibers may have a composition similar to or identical to the composition of the splittable filament retaining element. Additionally, the plurality of reinforcing filaments or fibers may be defined as fibrillated reinforcing filaments, which may be imparted with tension to further encourage dispersion upon release from the retaining element. The reinforcing filaments or fibers may further be defined as being formed from a super absorbent polymer composition.
[0019] In yet another embodiment the unitized fibrous construct for reinforcing a cementitious mixture includes a plurality of reinforcing filaments or fibers oriented in a generally parallel relationship such that the plurality of reinforcing filaments or fibers form a unit having a circumferential exterior surface. The construct also includes a retaining element formed of a super absorbent polymer composition that surrounds at least a portion of the circumferential exterior surface and retains the plurality of reinforcing filaments or fibers prior to adding the construct to the cementitious mixture. Typically, the super absorbent polymer composition retaining elements will provide reinforcing capabilities once they have been added to the cementitious mixture.
[0020] The reinforcing filaments or fibers may have a composition similar to or identical to the composition of the super absorbent polymer composition retaining element. Additionally, the plurality of reinforcing filaments or fibers may be defined as fibrillated reinforcing filaments, which may be imparted with tension to further encourage dispersion upon release from the retaining element. The reinforcing filaments or fibers may further be defined as being formed from a super absorbent polymer composition.
[0021] Thus, the present invention is able to provide for a cementitious reinforcing construct that includes a retaining element that imparts reinforcing structure into the cementitious mixture. Such a construct benefits from not having a retaining structure that disperses or otherwise dissolves in the aqueous cementitious mixture and imparts possible negative side-effects to the cementitious mixture, such as voids, strength reducing mold and the like. Additionally, the reinforcing aspect of the retaining element provides for a construct that is able to provide additional per unit reinforcement of the cement mixture.
BRIEF DESCRIPTION OF THE DRAWING
[0022] FIG. 1 is an illustrative embodiment of the unitized fibrous construct of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] While the present invention is susceptible of embodiments in various forms, hereinafter the present invention is described by presently preferred embodiments with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.
[0024] Referring to FIG. 1 , therein is illustrated an embodiment of a unitized fibrous construct of the present invention. The unitized fibrous construct is added to a castable mixture, such as a cementitious mixture to provide added reinforcement, resulting in greater strength, stability and crack-resistance. The unitized fibrous construct 10 is defined herein as a construct including a plurality of oriented reinforcing continuous filaments or finite staple length fibers 12 . The filaments or fibers 12 are arranged in a general parallel relationship such that the filaments or fibers form a bundle. While the bundle will typically have a general cylindrical shape, the bundle may also have any other shape, for example oval, square, triangular, etc. The plurality of filaments or fibers 12 will be bundled such that they form a circumferential exterior surface 14 .
[0025] The construct further includes one or more retaining elements 16 that surround at least a portion of the circumferential exterior surface 14 and serve to retain the reinforcing filaments or fibers 12 prior to adding the construct 10 to a castable mixture, such as a cementitious mixture. The retaining element will serve as a reinforcing element upon once added to the castable mixture, such as a cementitious mixture.
[0026] In order for the retaining element 16 to serve as a reinforcing element upon addition to the castable mixture the retaining element will typically be formed of a similar, and in some embodiments identical, fibrous or filamentary material, denier, and length as the reinforcing fibers or filaments 12 . Further still, in alternate embodiment the retaining element 16 may be of a dissimilar fibrous or filamentary material, denier, and length as the reinforcing fibers or filaments 12 . In those embodiments in which the retaining element is a dissimilar fibrous or filamentary material compared to the reinforcing fibers or filaments, the retaining element will be formed of a material that allows for the retaining element to provide reinforcing characteristics upon addition to the castable mixture.
[0027] Typically, the unitized fibrous construct of the present invention is formed from a plurality of reinforcing fibrous or filamentary components and one or more circumferential retaining elements. The composition of such reinforcing fibers and circumferential retaining element may be formed from any suitable synthetic polymers, including, but not limited to, thermoplastic and thermoset polymers, including polyesters, polyolefins, such as polypropylene and polypropylene copolymers, polyethylene and polyethylene copolymers, polyamides, polyimides, polylactic acid, polyhydroxyalkanoate, polyvinyl alcohol, ethylene vinyl alcohol, polyacrylates, copolymers thereof, and the combinations thereof. Additionally the reinforcing fibers or filaments and the circumferential retaining element may be formed from any suitable natural fibers, including, but not limited to rayon, cotton, pulp, flax, and hemp and the combinations thereof. A particularly preferred embodiment of the present invention is directed to reinforcing fibers or filaments including polyolefin thermoplastic resins.
[0028] In one embodiment of the invention the retaining element that surrounds a portion of the exterior surface includes splittable filaments, which may be of similar or dissimilar polymeric composition in relation to the reinforcing fibers or filaments. Suitable splittable fibers are taught in U.S. Pat. No. 6,838,402, issued on Jan. 4, 2005, in the name of inventors Harris, et al.; U.S. Pat. No. 6,746,766, issued on Jun. 18, 2004, in the name of inventors Bond, et al.; U.S. Pat. No. 6,743,506, issued on Jun. 1, 2004, in the name of inventors Bond et al.; and U.S. Pat. No. 6,444,312, issued on Sep. 9, 2002, in the name of inventor Dugan, all of which are herein incorporated by reference as if set forth fully herein.
[0029] In embodiments in which the retaining element is splittable filaments, the plurality of reinforcing filaments may be fibrillated, wherein the filaments may be fibrillated by any conventional fibrillation technique, such as by mechanical fibrillation described in U.S. Pat. No. 3,302,501, issued on Feb. 7, 1967, in the name of inventor Greene; U.S. Pat. No. 3,496,260, issued Feb. 17, 1970, in the name of inventors Guenther et al.; U.S. Pat. No. 3,550,826, issued Dec. 29, 1970; in the name of inventor Salmela; and U.S. Pat. No. 3,756,484, issued Sep. 4, 1973, in the name of inventor Guenther, or by fluid and sonic fibrillation as disclosed in U.S. Pat. No. 3,345,242, issued Oct. 3, 1967, in the name of inventor Rasmussen, all of which are hereby incorporated by reference as if set forth fully herein. In addition, the reinforcing filaments may be imparted with tension by way of twisting the filaments as well. Tension imparted in the reinforcing filaments will cause greater dispersion of the filaments once the retaining element has been removed from the construct/bundle of filaments.
[0030] Additionally, in embodiments in which the retaining element is splittable filaments, the plurality of reinforcing fibers or filaments may be formed from a super absorbent polymer composition. Exemplary super absorbent polymers are disclosed in U.S. Pat. No. 5,145,609, issued Sep. 8, 1992, in the name of inventor Chambers; U.S. Pat. No. 4,820,773; issued Apr. 11, 1989, in the name to inventors Alexander et al.; and U.S. Pat. No. 4,645,039, issued Mar. 31, 1997; in the name of inventor Brandt et al., all of which are herein incorporated by reference as if set forth fully herein.
[0031] In another embodiment of the invention the retaining element that surrounds a portion of the exterior surface may include a super absorbent polymer composition. Exemplary super absorbent polymers are disclosed in the previously referenced and incorporated patents.
[0032] In those embodiments in which the retaining element is formed of a super absorbent polymer composition, the reinforcing fibers may include splittable fibers. Suitable splittable fibers are taught in the previously referenced and incorporated patents.
[0033] According to the present invention, the retaining element surrounds at least a portion of the circumferential exterior surface of the construct. Once formed, the retaining element aids in maintaining the integrity of the unitized fibrous construct, and the reinforcing fibrous component therein, for the purposes of shipment, measurement, and dosing into a cementitious mixture. Upon mechanical agitation, and optionally exposure to appropriate solvents, the unitized fibrous construct in a cementitious mixture, the retaining element are disrupted, allowing for the homogenous release, distribution, and disbursement of the reinforcing fibrous component into the overall cementitious mixture. The unitized fibrous construct of the present invention is believe to reduce plastic shrinkage cracking by at least 10% per ASTM 1399, Obtaining Average Residual Strength of Fiber Reinforced Concrete.
[0034] A number of suitable methodologies exist for the formation of unitized fibrous constructs in accordance with the present invention. A preferred, though non-limiting, method is taught in part by U.S. Pat. No. 4,228,641, issued on Oct. 1, 1980, in the name of inventors O'Neil, this patent is herein incorporated by reference as if set forth fully herein. The '641 O'Neil patent teaches a twine including a core bundle of synthetic monofilaments circumscribed by a synthetic material in a thin band form spirally wound about the monofilaments. It has been found by the inventors of the present invention that by practice of the method taught in the '641 O'Neil patent, with subsequent and repeated scission of the continuous twine construct at or between each iteration of the spiral winding that finite length unitized fibrous constructs are formed which are suitable for practice in light of the present invention.
[0035] The dimensions of the retaining element is defined in terms of the overall circumference of the exterior surface formed by the reinforcing fibers or filaments, as based on the quantity and relative denier of the individual reinforcing fibrous components, and of length, as based on the greatest finite staple length of the cumulative combination of reinforcing fibrous components. Suitable overall circumferences and lengths of the circumferential retaining elements formed in accordance with the present invention may reasonably range from 3 mm to 150 mm and from 8 mm to 100 mm, respectively. In a presently preferred embodiment for standard practices, circumferential retaining elements exhibit an overall diameter of between 3 mm and 30 mm and lengths of between 12 mm and 50 mm may be utilized. Further, the circumferential retaining elements may exhibit a width preferably about 1%-50% of the total diameter of the unitized fibrous construct, more preferably about 3%-40% of the total diameter of the unitized fibrous construct, and most preferably about 5%-30% of the total diameter of the unitized fibrous construct. Further still, the circumferential retaining element is preferably about 2%-50% by weight of the unitized construct including parallelized reinforcement fibers, more preferably of about 6%-40% by weight of the unitized construct, and most preferably of about 8%-30% weight of the unitized construct.
[0036] The circumferential retaining element may include one or more continuous or discontinuous filaments, ribbons, or sheets of varying thicknesses that retain the reinforcing fibrous components by a plurality of wrapping techniques so as to expose more or less fiber to the external environment. For instance, two thin circumferential retaining elements may be used in a double helix wrapping technique, whereby two circumferential retaining elements criss-cross back and forth about the circumference of the fibrous components.
[0037] Thus, the present invention is able to provide for a cementitious reinforcing construct that includes a retaining element that imparts reinforcing structure into the cementitious mixture. Such a construct benefits from not having a retaining structure that disperses or otherwise dissolves in the aqueous cementitious mixture and imparts possible negative side-effects to the cementitious mixture, such as voids, strength reducing mold and the like. Additionally, the reinforcing aspect of the retaining element provides for a construct that is able to provide additional per unit reinforcement of the cement mixture.
[0038] From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims. | A unitized fibrous construct for providing reinforcement to castable structures, such as cementitious structures is claimed. The construct includes a bundle of reinforcing fibers or filaments that are held in place prior to addition to the cementitious mixture by a retaining element. The retaining element is of such a composition that upon release into the cementitious mixture it provides reinforcing capability to the cement structure. As such, the construct adds additional reinforcing capability and diminishes the likelihood of detrimental side-effects attributed to retaining elements that otherwise dissolve or disperse in the cementitious mixture. | 4 |
[0001] The technology disclosed herein relates generally to rotary machines and, more specifically, to wedges used for the retention of conductor (or stator) bars in the stator core slots of dynamoelectric machines.
BACKGROUND
[0002] Large dynamoelectric machines such as electrical generators employ a laminated stator core for transmitting induced voltages to the generator terminals through stator conductor bars. The cores are usually made by assembling already-slotted punchings or laminations in an annular housing for later enclosing the generator rotor. The slotted punchings, when assembled, define axially-extending, radially-oriented core slots which terminate at the radially inner-circumference of the stator annulus. The stator bars, or conductors, with ground insulation are laid in the radial slots and a wedging system is used to hold the bars in place against electromagnetic forces present when the machine is operating. If the wedging system is not effective, ground or conductor insulation may be damaged in the ensuing vibration, ultimately leading to a forced outage of the generator.
[0003] Electromagnetic fields in the generator induce forces on stators bars during normal operation or short circuit conditions that require wedges to support and restrain the bars within the stator core slots.
[0004] Currently fiberglass laminate material (such as, for example, National Electrical Manufacturers Association (NEMA) G11 is used in making the wedges, and while G11 provides good mechanical strength, it is abrasive to the stator laminations.
[0005] Cotton phenolic material has also been used as a wedge material, and while it is non-abrasive to the core, it has lower thermal and mechanical capability versus fiberglass laminates such as G11. The reduced mechanical strength and thermal capability of cotton phenolic thus limits the application of wedges made using this material. Other solutions such as low friction coatings have also been tried.
[0006] In U.S. Pat. No. 4,200,818, there is disclosed a stator wedge partially covered with a non-woven felt made of Kevlart, and in U.S. Pat. No. 4,607,183 there is disclosed a wedge with an abrasion resistant layer. In commonly owned, co-pending application Ser. No. 11/889,928, wedge bodies having surfaces in contact with the core are disclosed wherein at least the contact surfaces are covered with a woven aramid fabric material.
BRIEF SUMMARY OF THE INVENTION
[0007] In one aspect, the present invention relates to a slot wedge for a stator adapted for use in a dynamoelectric machine comprising a wedge body having opposite side edges adapted to engage complimentary stator core slots, wherein at least the side edges are covered with an aramid paper material.
[0008] In another aspect, the invention relates to a slot wedge for a stator adapted for use in a dynamoelectric machine comprising a wedge body having opposite side edges adapted to engage complimentary stator core slots, the side edges each having a semi-circular shape, wherein at least the side edges are covered with a woven aramid fabric or an aramid paper material.
[0009] In still another aspect, the invention relates to a method of making a slot wedge for a stator adapted for use in a dynamoelectric machine comprising: (a) providing a fiberglass wedge body formed to a predetermined shape, including opposite side edges adapted for engagement within stator core slots; and (b) covering at least the opposite side edges of the wedge body with an aramid paper material.
[0010] Exemplary but nonlimiting embodiments of the invention will now be described in detail in connection with the drawings identified below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a partial perspective view of a lower portion of a generator stator showing conventional dovetail wedges;
[0012] FIG. 2 is a perspective view of a pressure wedge in accordance with this invention;
[0013] FIG. 3 is a perspective view of another pressure wedge in accordance with the invention; and
[0014] FIG. 4 is an end elevation of still another wedge in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] FIG. 1 of the drawings shows a lower portion of a dynamoelectric machine stator core 10 . The dynamoelectric machine has a rotor (not shown) and a stator core, the latter being an annular structure which encloses (i.e., surrounds) the rotor when the rotor is assembled within the dynamoelectric machine. The stator core is assembled from a plurality of slotted punchings or laminations 12 . The stator core 10 is formed with variable number of radially-oriented slots 14 spaced circumferentially around the inner annulus perimeter (only one shown), and which extend along the axial length of the stator core and terminate at their radially inner portions in, for example, a dovetail-shaped slot 16 , as well understood in the art. The conductors 18 comprise insulated conductor strands including radially inner and outer bars 20 and 22 , respectively. The conductors or conductor bars typically include electrical insulation 23 wrapped about the perimeter portions of conductor packages.
[0016] In conjunction with the foregoing, a filler strip 24 may extend axially (longitudinally) along the slot radially inward of bar 22 . A number of dovetail wedges 26 are introduced into the slot 14 (and spaced apart along the axial length of the slot 14 ) so as to bear radially against the insulating filler strip 24 . More typically, a ripple spring (not shown in FIG. 2 ) is interposed between the filler strip and the wedge. In other arrangements, the wedge (or wedges) is formed with an inclined bottom surface and a tapered slide is driven under the wedge to tighten it. In the latter arrangement, a top ripple spring may be located below the slide and on top of any one or more filler strips. As the slide is driven under the wedge, the ripple spring compresses to enhance the restraint of the stator bars in the core slots. It will be appreciated that the invention described herein is applicable regardless of wedge shape and regardless of whether slides, filler strips or ripple springs are employed.
[0017] The dovetail wedges are typically formed with oppositely-facing inclined surfaces 28 which engage inclined surfaces of the dovetail slot 16 to facilitate the assembly of the stator bar wedging system. The material used for the dovetail wedges 26 is preferably of high-strength insulating material which can be cut or molded to the desired wedge shape. The wedges are thus preferably formed of a molded resinous compound employing a suitable filler to add strength, or in the alternative, are formed of any suitable commercially-obtainable cotton phenolic materials such as Textolite® (a registered trademark of the General Electric Company). In some designs, however, and as noted above, cotton phenolic wedge by itself lacks the required mechanical strength for thinner and/or wider wedge configurations. It will be understood that the length of the wedges 26 may vary from what is shown in FIG. 1 .
[0018] With reference to FIG. 2 , and in accordance with a first exemplary, non-limiting implementation of the technology disclosed herein, a wedge 30 is constructed of, for example, fiberglass laminate G11 material which is partially or completely covered with at least one layer of an aramid paper material. The aramid paper prevents the fiberglass from directly contacting and helps reduce wear on the laminate punchings (i.e., the core slots). In addition, the aramid paper should provide adequate abrasion and tear resistance, and may also improve thermal capability, mechanical strength and dimensional stability. Preferably, the aramid paper covers at least the inclined side (or dovetail) edges or surfaces 34 , 36 , but as a practical manufacturing matter, the top surface 38 and or the bottom surface of the wedge may be covered.
[0019] One commercially available aramid paper well suited for use in this invention is available from E.I. du Pont de Nemours and Company, and sold under the trade name NOMEX®.
[0020] In a first exemplary process, the wedge itself is made from a prepeg fabric, a bulk molding compound, or a liquefied resin (e.g., G11) poured into a mold cavity containing a woven glass roll the length of the wedge 30 . The aramid paper 32 may be applied to the wedge by molding, pultrusion, extrusion or by gluing the paper to the wedge. Molding, pultrusion and extrusion, where the surface applied integrally to the part (or wedge), producing the part in one step, are preferred over adhesive due to better bonding which prevents surface layer separation.
[0021] In another exemplary but nonlimiting embodiment illustrated in FIG. 3 , the fiberglass wedge 40 is formed with semi-circular edges 42 , 44 for use with core slots having complimentary shapes. Here again, the edges 42 , 44 which engage the core slot may be covered with strips 46 , 48 of an aramid paper (or a woven aramid fabric such as Kevlar®, Twaron® and Kernel®,) as described above. In addition, the top and/or bottom surfaces of the wedge may be covered as well. The materials and processes used in the manufacture of the wedge 40 and the application of the cover material may also be as described above.
[0022] With reference now to FIG. 4 , still another exemplary wedge 50 is illustrated. Here, the edges 52 , 54 of the wedge have an arrow-shape, again to match a corresponding core slot shape. As in the previously described embodiments, strips 56 , 58 of aramid paper or aramid fabric may be applied along the side edges 52 , 54 , and, if desired, along the top and bottom surfaces as well.
[0023] It will be appreciated that the invention is equally applicable to wedges having other dimensional proportions (e.g., length to width ratios, thickness, etc.), and/or different edge shapes (e.g., oval, square, etc.) which engage the core slots, and thus the above-described embodiments are intended to be merely exemplary and nonlimiting. In addition, the core slot engaging surfaces may be continuous or intermittent along the length of the wedge bodies. For example, the dovetail surfaces could be notched at spaced locations along their respective lengths to enhance air flow and cooling.
[0024] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | A slot wedge for a generator stator includes a wedge body having opposite side edges adapted to engage complimentary stator core slots. At least the opposite side edges are covered with an aramid paper or woven aramid fabric material. | 7 |
CROSS-REFERENCE TO A RELATED APPLICATION
The invention described and claimed hereinbelow is also described in German Patent Application DE 10 2007 030 168.7 filed on Jun. 27, 2007. This German Patent Application, whose subject matter is incorporated here by reference, provides the basis for a claim of priority of invention under 35 U.S.C. 119(a)-(d).
BACKGROUND OF THE INVENTION
The present invention is based, in general, on the field of agriculture and the processing of harvested crops. Vehicles designed to pick up and process crops—self-propelled agricultural harvesting machines in particular—are used for this purpose. The self-propelled agricultural harvesting machines are typically combine harvesters, forage harvesters, and all types of lifters that are equipped with electronic control devices for drive units. Some of the drive units act on the ground drive, which is composed of an all-wheel drive that acts on all of the wheels, and/or a track roller unit in contact with the ground.
The front wheels of a harvesting machine may be composed of a track roller unit with two large guide wheels. The wheels are driven by a main engine, which is designed, e.g., as an internal combustion engine, by a hydraulic pump, and at least one hydraulic motor, which is connected with the hydraulic pump, converts the hydraulic energy into mechanical work, and drives at least one wheel that is engaged with the ground. Electronic controls and actuators are used to control and regulate the hydraulic motors, which, as drive units, drive front and rear wheels using a hydrodynamic transfer of force. Control units that control the drive torque at the wheels are used to obtain good traction and minimize the slippage of the wheels on the ground. Sensors that process the signals from the control devices are used at particular points in the self-propelled harvesting machine to control the drive torques.
Various systems are known from the related art for increasing the traction of vehicles and reducing the tire slip between the drive wheel and the ground.
One such system is an all-wheel drive, with which—in complete contrast to front-wheel drive or rear-wheel drive—the engine force of a vehicle acts on all wheels in contact with the ground, in order to ensure that the vehicle may travel across rough terrain at all. All-wheel drive increases traction by distributing the drive torques and improving driving stability, and it is adequately known from the related art. With vehicles with permanent all-wheel drive, engine power is transferred constantly to all four wheels, and differentials ensure that the rotational speed is fully equalized and that power is not lost. To prevent strain from occurring in the drive train, an additional central differential is installed between the front and rear axles. The disadvantage of this is that, if any single wheel or axle has inadequate traction or no traction, the amount of drive torque that may be transferred by this wheel or axle is limited. As a result, in the extreme case, the vehicle becomes unable to move under its own force.
Assistance in these cases is provided by a special transmission and an electronic control, referred to as VDC (vehicle dynamic control). The special transmission compensates for the unequal weight distribution between the axles of the agricultural machines by dividing the force between the front and rear axles at a ratio of, e.g., 35:65. The electronic control compares the wheel speeds and steering angle specified by the drive, to detect overcontrol or undercontrol and to modify the force distribution such that the vehicle retains a neutral self-steering effect.
Publication DE 199 21 856 A1 discloses a hydrostatic-mechanical all-wheel drive for multiple-axle vehicles that makes it possible to distribute the ground drive output to the driving axles with consideration for the traction that exists between the vehicle tires and the ground. The drive presented ensures automatic, stepless adjustment of the speed ratios, but it may also be supported via regulator intervention depending on the steering angle, thereby resulting in torque being distributed to the drive axles by changing the rotational speed ratios. Strain is thereby prevented, as described previously in the related art, even when driving through tight turns. Output is distributed such that wheel slip is kept the same between all driven wheels, even when the loads on the vehicle axles change.
The disadvantage of this drive system is that the control and regulating device measures only a few parameters of the vehicle. As a result, power distribution, which is carried out by adjusting the hydraulic motors, does not take place under all driving and harvesting conditions.
The aforementioned control and regulating device is referred to as ASR (anti-slip regulation) or TCS (traction control system), and is known from the related art. Anti-slip regulation ensures that the wheels do not spin when they are accelerated. When giving too much gas at start-up or if the terrain is poor and static friction is minimal—circumstances which occur very often in agriculture—one or more wheels may spin, and the vehicle becomes unstable. The spinning of one or more wheels on the ground is referred to as tire slip. To ensure a maximum transfer of friction force between the tires and the various ground conditions in fields, and in various weather conditions, ASR is used to prevent wheels from spinning and/or to prevent undercontrol and overcontrol of the vehicle. If there is a risk of serious slip of the drive wheels, the drive torque is regulated via targeted intervention by the braking system and/or engine management system.
The closed-loop control system, which receives its information, e.g., from the ABS wheel speed sensors, therefore ensures traction and driving stability during the acceleration phase on a straight path, even when driving around turns. ABS stands for “antilock braking system” and also improves the driving safety of agricultural vehicles. It functions mainly in certain situations of hard braking by regulating the braking pressure in short intervals to counteract the tendency of the wheels to lock up. ABS is also capable of controlling the braking behavior of each individual wheel in a nearly optimal manner. The ESP (electronic stability program) also prevents slip and the undercontrol or overcontrol of a vehicle using electronic sensors, the signals of which are evaluated and processed in a system, by braking individual wheels in a specific manner.
The system ascertains the driving behavior in this manner and intervenes when a deviation from the driver's information setting is determined. The change in steering angle is also taken into consideration. Hydraulic motors may be braked by changing the volumetric flow rate of the hydraulic fluid.
The ESP, ASR, and ABS control systems do not meet the requirements placed on drive wheels of motor vehicles, however, in particular on agricultural harvesting machines, for attaining optimal traction and limiting it such that tire slip may be adequately prevented under specific harvesting conditions.
Publication EP 1 350 658 B1 makes known a control device for an hydraulic all-wheel drive that controls actuators using signals generated by sensors (a speed sensor and a pressure sensor). The actuators influence two drivable axles or hydraulic motors assigned to the axles by changing the intake volume, in order to obtain optimal traction at the drive wheels. This type of control not only takes the aforementioned driving behavior into account, but also the load distribution on the front and rear axles when driving up or down hills, thereby making it possible to prevent the familiar “back-spin” effect. When the loads on the axles change when driving up or down hill, this is compensated for by changing the drive output at the wheels. The axle loads are not actually measured, however. Instead, the operating state of the hydraulic motor is ascertained via a pressure sensor, the signal of which contains information about the pressure difference between the inlet and outlet channels in the hydraulic motor, and via the speed sensor signal. Based on the signal from the pressure sensor, it may be determined whether the wheel is driving the vehicle, or whether the wheel is spinning. The disadvantage of this system is that the slip of one or more wheels is not detected at an early stage, and it cannot be counteracted until after slip has already occurred.
Publication EP 1 232 682 B1 describes an electronic engine control for an internal combustion engine. Performance curves for controlling the internal combustion engine are stored in the control. The performance curves contain information about engine output as a function of various parameters, e.g., engine speed, temperature, the drive of the attachments and devices, etc. According to the present invention, the control contains machine parameters of crop material-gathering devices. When a different crop material-gathering device is used, this is detected via sensors. A sensor may be a switch in the driver's cab, which the driver may operate. When a different crop material pick-up device is used, the performance curve of the internal combustion engine is changed in the engine control. The change to the performance curve results in the output of the internal combustion engine being regulated up or down. The performance of the internal combustion engine is therefore regulated depending on the front attachment that is used. The drive torque of the individual drive wheels at the hydraulic motors is not regulated, however.
SUMMARY OF THE INVENTION
The present invention is therefore based on the object of creating a control device of the type described initially that prevents the aforementioned disadvantages of the known controls described in the related art, and it provides a technical solution that makes it possible to limit the drive torque of the drive wheels such that the wheels and/or tires are prevented from slipping on the ground, thereby ensuring that the maximum possible amount of drive torque may be transferred. With self-propelled agricultural harvesting machines that have four drive wheels, the interplay of the individual drive wheels under different traction conditions is therefore very significant.
In keeping with these objects and which others which will become apparent hereinafter, one feature of the present invention recites, briefly stated, in an electronic control device ( 26 ) for a drive unit of a vehicle, in particular a self-propelled agricultural harvesting machine with all-wheel drive, which is composed of a main engine, a hydraulic pump and at least one hydraulic motor, which drives the at least one wheel that is engaged with the ground, wherein traction is optimized and slip is prevented at least one wheel by specifying the torque required at the hydraulic motor depending on the application.
To equip vehicles—self-propelled agricultural harvesting machines in particular—with an electronic control device for ground drives having the features of the present invention, it is provided according to the present invention that the torque required at the hydraulic motor be specified depending on the particular application, to optimize traction and prevent slip by at least one wheel. Advantageously, the torque applied at the hydraulic motor is adapted to changing harvesting conditions such that wheel slip or spin is reduced or even prevented. The amount of wheel torque required is advantageously determined by the particular application of the vehicle. “Application” refers to the equipment used on the vehicle, or the conditions under which it is used.
The control conditions made known in the related art, e.g., ASR, cannot limit slip until it occurs at a drive wheel to a measurable extent. By this time, however, the topsoil has already been damaged, when the harvesting machine is used to pick up crops in a field. The torque of the hydraulic motor that is produced depends on the speed. The speed, in turn, depends on the volumetric flow rate, the pressure supplied by the hydraulic pump, and on the intake volume, while the drive torque for the drive wheel produced by the hydraulic motor is determined by the load pressure and the intake volume. “Intake volume”, in the context of the fluid technology of hydraulic motors, refers to the quantity of hydraulic fluid that the hydraulic motor consumes per revolution. The intake volume is variable with regulatable hydraulic motors of the type under discussion here. That is, the output provided by the hydraulic motor to the drive wheel is proportional to the intake volume, speed, and pressure difference. The product of the intake volume and speed is the volumetric flow rate. The pressure difference is the difference between the pressure of the hydraulic fluid flowing into the hydraulic pump and the pressure of the hydraulic fluid flowing out of the hydraulic pump. This results in a further inventive requirement, namely to determine the intake volume required at the hydraulic motor in an application-specific manner, since it is proportional to the torque requirement and the power output of the hydraulic motor.
The torque and intake volume required to obtain a maximum possible wheel torque at one or more wheels are determined based on additional data that has been measured and/or determined via sensor signals. The data and/or signals are registered in an inventive electronic control device, which evaluates the data and signals and, based thereon, calculates the intake volume required for the hydraulic motors. The sensor signals are obtained, e.g., from speed sensors located on the drive axles. The data are composed of machine parameters, which include static and dynamic machine parameters, because the devices on which the machine parameters are based primarily influence the wheel load and/or traction of the wheels. The devices are the static machine equipment, which is used to determine the wheel load-dependent machine parameters. The static machine equipment includes, e.g., the type of crop material pick-up device attached to the self-propelled harvesting machine; this information is supplied to the control device along with the model, equipment type, and working width, and, therefore, different machine parameters. The type of vehicle, the tires used, and the motors used to drive them are taken into account in the control device with the different machine parameters.
Different crop material pick-up devices obviously affect the wheel and axle load on the drive wheels, and therefore seriously affect the traction and slip behavior of the drive wheels. It is therefore provided according to the present invention that the wheel load of at least one hydrostatically driven wheel be determined indirectly, and that the axle or wheel torque be adjusted depending on the wheel load that was determined. Further static machine parameters, which are supplied to the control device as data for calculating the control of the intake volume requirement of the drive wheels, are additional weights, which result, e.g., from the different technical equipment attached to the rear of the harvesting machine. The type of crop material to be processed is also taken into account as a machine parameter, because there are differences between grass, corn, grain, and other types of crops in terms of the weight for the wheel load and the terrain characteristics.
When the agricultural machine is used, e.g., to harvest grass, on a dry field, or to cut low-lying grass, high forward-travel speeds with adequate tractive force are required. When harvesting corn, however, when the soil is heavy and moist, and/or when a crop material hauling trailer is attached to the vehicle, the full tractive force is required at a low forward-travel speed. These different application-dependent requirements on traction and, therefore, the hydraulic drive units, are taken into account in the inventive specification of intake volume by the control device. Basically, the static machine parameters of the machine equipment are determined, and they are incorporated in the control device program in order to calculate the amount of torque required. The static machine parameters may be changed manually in the control device program at any time by the driver accessing a menu item of the control system, thereby making it possible to optimize traction and reduce slip at any time.
Manual intervention by the driver in the control is not possible when ASR or ESP controls are used, however. All that can be done with these systems is to turn the controls completely on or off.
Advantageously, the dynamic machine parameters are also included in the control device program, thereby ensuring that the value for the specified intake volume may be calculated in a more targeted manner. The dynamic machine parameters and/or their variable mass on which they are based, the variable direction, inclination, and/or ground speed of the vehicle are measured, because they also affect the wheel and axle load and, therefore, the traction and slip of the wheels. The variable dynamic machine parameters are therefore also used, according to the present invention, to calculate the intake volume required, in order to obtain optimal traction at an individual driving wheel or at several driving wheels at any time, and to prevent slip of one or more driving wheels.
Variable dynamic machine parameters result, e.g., from the variable position of the crop material pick-up device, the ground speed, and the steering angle of the vehicle. The parameters of the vehicle inclination—as made known in publication EP 1 350 658—and the vehicle acceleration in the longitudinal and transverse directions—as known from the ASR system—are also taken into account in the control device. A further object of the present invention for ascertaining the axle load is to detect the variable fill level of the tank container and, with combine harvesters, the variable fill level of the grain tank, and to also take this information into account. The dynamic machine parameter of the oscillating position of the axle is also included in the control device program. A further embodiment of the present invention includes indirect determination of the wheel load, e.g., using a load sensor located in the swing-axle suspension.
These variable dynamic machine parameters are measured using sensors, the signals of which are processed in the electronic control device along with the data on the static machine parameters, and based on which the values for the required torque are determined. The intake volume required by the hydraulic drive motors is regulated based on the values of the torque requirement that are determined. That is, the torque requirement determined based on the static and dynamic machine parameters approximately corresponds to a specified performance curve for the hydraulic motor, similar to the performance curve for the internal combustion engine that is stored in a control device.
The specified performance curve for the hydraulic motor that is calculated based on the machine parameters depends on wheel load; it is used to adjust the drive torque by controlling the intake volume of at least one hydrostatically driven wheel, and it is preferably used with all drive wheels. The performance curve contains data that applies to the variable traction and slip situation of every individual drive wheel. If, e.g., the position of the crop material pick-up device changes, the load on the front and rear axles changes, thereby also resulting in a change, disadvantageously, to the traction, steering behavior and slip conditions at the drive wheels. To offset these disadvantageous changes, the torque applied at the drive motors is changed based on the dynamic machine parameters of the crop material pick-up device contained in the performance curve, according to the present invention.
The change in the torque results in an increase in the tractive force at the hydraulic drive motors of the front axle by changing the intake volume requirement, and it results in a decrease in the tractive force at the drive motors of the rear axle. In addition, the torque between the left and right drive motor changes when entering a turn. In this case, the intake volume delivered to the individual drive motors is controlled such that optimal traction occurs at the drive wheels, and undesired slip of an individual drive wheel that could occur due to the conditions for use that were detected is prevented in advance. Different weight distributions on the axles of the harvesting machine are therefore determined indirectly to specify the intake volume required for the hydraulic motors. The application-dependent specification takes place by distributing torque automatically—also known as controlled longitudinal differential—between the front and rear axles. The torque distribution may vary between 60 to 40 and 90 to 10, and preferably 80 to 20, depending on what type of equipment is installed on the machine.
In a simple embodiment of the present invention, only the torque requirement is controlled, according to the present invention, based on the crop material pick-up device being used. The operator may intervene manually in the control device using the control system in order to account for any slip at the wheels that he observed during use of the vehicle. Advantageously, and according to the present invention, the intake volume specified for every wheel or axle, and a requirement for the distribution of axle load may be changed, and the application-dependent torque requirement may be changed manually. The requirement for a wheel may therefore be acted upon with an offset value, which is then retained for every further application-specific torque requirement for this crop material pick-up device. Assistance is therefore advantageously provided, in particular, in cases of poor traction due to unusual terrain conditions.
In a special embodiment of the present invention, traction is measured using a slip sensor, the control device is accessed, and the required intake volume is automatically adjusted. A radar sensor is suited for this purpose, for instance, which measures the actual ground speed of the vehicle and, in combination with the wheel speeds, makes it possible to determine slip. By correcting the specified intake volume, and when the slip is known, further slip may be advantageously prevented from occurring.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, 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 schematic depiction of a drive system of an all-wheel drive vehicle, in particular a self-propelled agricultural harvesting machine with an electronic control device for the drive units, and
FIG. 2 is a perspective illustration of an inventive electronic control device in a further exemplary embodiment of a ground drive.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a schematic depiction of an embodiment of a drive unit of an all-wheel drive vehicle, in particular a self-propelled agricultural harvesting machine 1 with an inventive electronic control device 26 for the hydraulic drive units of the ground drive. Harvesting machine 1 includes a (not-shown) frame or a self-supporting chassis, which rests on front wheels 19 , 20 and rear wheels 24 , 25 , which are engaged with the ground. Rear wheels 24 , 25 are typically located such that they are steerable, while front wheels 19 , 20 have a larger tire diameter than do rear wheels 24 , 25 , and they carry most of the weight of the vehicle, in particular in the embodiment as a harvesting machine 1 , e.g., a combine harvester. Front wheels 19 , 20 of a harvesting machine 1 may also be a track roller unit (not shown), in which case a roller unit corresponds to a drive wheel 19 , 20 . Due to the different weight distribution of the vehicle on front axle 16 and rear axle 21 , traction also differs at front drive wheels 19 , 20 and rear drive wheels 24 , 25 . Traction is less critical for drive wheels 19 , 20 mounted on front axle 16 , due to their greater wheel load, than drive wheels 24 , 25 mounted on rear steering axle 21 .
The drive unit includes a main engine 2 , which is an internal combustion engine, preferably a diesel engine, which drives various material processing and conveying devices. The drive unit drives the ground drive of harvesting machine 1 . The ground drive is driven via a shaft 3 of main engine 2 to hydraulic pump 5 , the fluid displacement of which converts mechanical power into hydraulic power (pressure×volumetric flow rate) using a tilt-box (see FIG. 2 ), which is controllable. The control of hydraulic pump 5 will not be discussed further here, because it is assumed to be known. A transmission 4 (shown as a dashed line) may be located between main engine 2 and hydraulic pump 5 , as an alternative. Hydraulic pump 5 includes an outlet 6 and an inlet 15 . Outlet 6 is connected—as the supply—via hydraulic lines 7 and a distributor 59 with inlet 8 of hydraulic motors 9 , 10 , 11 , 12 , while outlet 13 of hydraulic motors 9 , 10 , 11 , 12 is connected—as the return—via hydraulic lines 14 with inlet 15 of hydraulic pump 5 .
Two of the hydraulic motors 9 , 10 are located on front axle 16 , and each hydraulic motor 9 , 10 is connected via a drive shaft 17 , 18 with a front wheel 19 , 20 . The two hydraulic motors 11 , 12 located on rear axle 21 are connected via a drive shaft 22 , 23 with rear wheels 24 , 25 . Rear axle 21 is preferably a swing axle, which is designed as a rigid axle and accommodates rear wheels 24 , 25 . The rigid axle is located in the center, under the rear end of harvesting machine 1 , and it is mounted to the machine frame using a bolt 60 oriented in the direction of travel. Bolt 60 makes it possible for axle 21 to oscillate transversely to the direction of travel, and it may be designed as a measuring bolt to determine the axle load.
A control device 26 is connected with a large number of sensors located in harvesting machine 1 , in order to pick up their signals 56 and process them. The sensors monitor the changes in the dynamic machine parameters. Some of these sensors are speed sensors 27 , which are located on drive shafts 17 , 18 , 22 , 23 , and which emit a pulse with each revolution of a drive shaft 17 , 18 , 22 , 23 , or several times per revolution. Sensors 28 that detect the current steering angle are located on rear axle 21 , which is steerable in design. Rear axle 21 is divided into two parts and is designed as a swing axle 29 , 30 . Swing axles 29 , 30 are equipped with sensors 31 , 32 that control the oscillating position of axles 29 , 30 . A transverse and longitudinal inclination sensor 38 is located on rigid front axle 16 , which delivers signals 56 for travel along a sloped hillside, or up or down hill. Further sensors 33 , 34 measure the fill level of fuel tank container 35 and grain tank 36 . A motion sensor 39 measures the motion, raising and lowering of a front attachment, e.g., a crop material pick-up device 37 , and its signal 56 is taken into account as a dynamic machine parameter in control device 26 .
Data 48 of the static machine parameters are also registered by control device 26 ; this takes place in a partially automated manner or via control functions 42 in control system 41 located in driver's cab 40 of harvesting machine 1 . Data 48 of the static machine parameters are specified primarily depending on which machine equipment is used. The static machine equipment includes, e.g., the type of crop material pick-up device 37 attached to self-propelled harvesting machine 1 ; this information is automatically supplied to control device 26 along with the model, equipment and working width, and, therefore, different machine parameters. In a refinement of the present invention, a sensor, which is not shown here, may be installed on harvesting machine 1 . The sensor automatically detects the presence of crop material pick-up device 37 used for harvesting and reports it to control device 26 . Crop material pick-up device 37 may also be equipped with a separate electronics module, which identifies itself to control device 26 , e.g., via a data bus connection. Various crop material pick-up devices 37 clearly determine the wheel and axle load on drive wheels 19 , 20 , 24 , 25 , and they affect the traction and slip behavior of drive wheels 19 , 20 , 24 , 25 . When a crop material pick-up device 37 is installed, e.g., if a pick-up (grass collector) is replaced with a corn header (corn pick-up), control device 26 automatically adjusts the torque requirements at hydraulic motors 9 , 10 , 11 , 12 .
The machine type of the vehicle and its engine type 2 are also taken into account in control device 26 , together with different machine parameters, via the programming of software 47 , before the vehicle is started up. Further static machine parameters, which are incorporated as data 48 in software 47 of control device 26 , include additional weight, which results, e.g., due to the different types of technical equipment attached to the rear of harvesting machine 1 , e.g., straw choppers and chaff spreaders. The machine parameter that is the type of crop material to be processed is also taken into account, because there are essential differences between grass, corn, and grain in terms of weight, which affects wheel load and traction. The moisture content of the crop material is also determined, using a moisture sensor 43 .
The ground condition is also taken into account as a parameter during harvesting, i.e., whether the ground is moist, heavy, or hard and dry, for example. The machine operator may gauge the condition of the ground himself and enter it via the control system. The ground condition may also be ascertained using a learning routine in that the drive unit of the vehicle is driven with different torque requirements over a certain period of time, and the torque required to obtain good traction without slip is selected manually or automatically. Electronic control device 26 measures all further machine parameters for this torque requirement that was determined, then controls the torque requirement based on the value that was learned, according to the present invention and depending on the particular application.
Further machine parameters may be drawn from other control devices 58 installed in the vehicle and then incorporated in control device 26 , so that they may be utilized to determine an optimal performance curve 49 .
Based on the static and dynamic machine parameters that were ascertained, values for the torque requirement are calculated using control device 26 , and a performance curve 49 for hydraulic motors 9 , 10 , 11 , 12 is determined. Performance curve 49 is used to specify the intake volume for hydraulic motors 9 , 10 , 11 , 12 . The required intake volume is controlled by regulating the hydraulic adjusting motor or tilt-box 44 of hydraulic motors 9 , 10 , 11 , 12 . In some systems, the adjusting motors are regulated using tilt-boxes or swash plates. An adjusting unit 45 (see FIG. 2 ) is provided for adjusting tilt-box 44 , which transfers the specified motion from control device 26 to tilt-box 44 . Adjusting unit 45 is preferably an electromechanical actuator.
A sensor 46 detects the current position of adjusting unit 45 , which is used to provide feedback to control device 26 and control a torque preselection and/or intake volume specification. Tilt-box 44 of hydraulic motors 9 , 10 , 11 , 12 is therefore controlled with reference to the wheel load-dependent machine parameters that were measured and evaluated, based on performance curve 49 contained in control device 26 , thereby resulting in an intake volume that may be regulated. Using control system 41 located in driver's cab 40 , the operator may manually intervene in control device 26 and displace performance curve 49 and/or the automatically specified torque with an offset, for one or more hydraulic motors 9 , 10 , 11 , 12 . The displacement may take place via a control function 42 , e.g., a rotary potentiometer. Performance curve 49 may be raised or lowered.
FIG. 2 is a perspective illustration of inventive electronic control device 26 in a further embodiment of a ground drive. Descriptions and details regarding the ground drive and control device 26 that are identical to those provided for FIG. 1 will not be repeated for FIG. 2 . Elements that are the same are labelled with the same reference numerals. The main difference from the ground drive depicted in FIG. 1 is that the all-wheel ground drive shown in FIG. 2 includes only two hydraulic motors 9 , 10 , each of which drives a differential gear 52 , 53 via a drive shaft 22 , 23 . First hydraulic motor 10 drives the two rear wheels 24 , 25 via a first drive shaft 50 and a first self-locking differential gear 52 .
Second hydraulic motor 9 drives the two front wheels 19 , 20 via a second drive shaft 51 and a second self-locking differential gear 53 . First hydraulic motor 10 may be switched on or off, so that the four-wheel drive feature may be switched on preferably only during the harvesting operation, when better traction is required, and it may be switched off during travel on the road. A multi-speed gearbox 54 (shown as a dashed line) with different, selectable gear stages may be provided between second hydraulic motor 9 and second differential gear 53 . Multi-speed gearbox 54 may include a reverse gear, for driving in reverse. The further alternatives to driving in reverse will not be described in greater detail here. As an alternative, a hydraulic wheel hub motor 55 (shown as a dashed line) may be located at the rear of harvesting machine 1 in place of first hydraulic motor 10 and first differential gear 52 at rear drive wheels 25 , 26 of rigid steering axle 21 .
As shown in FIG. 1 , control device 26 is connected with a large number of sensors, in order to measure the dynamic machine parameters. As shown in FIG. 1 , control device 26 calculates—based on the sum of data 48 of static machine parameters and the sum of signals 56 from the sensors of the dynamic machine parameters—the torque required, based on which a performance curve 49 is calculated, which, in turn, is used to determine the intake volume required for hydraulic motors 9 , 10 . Using aforementioned inventive control device 28 , it is possible to control the all-wheel function of self-propelled harvesting machines 1 with hydrostatically-driven drive wheels 19 , 20 , 24 , 25 such that traction is provided for hydraulic motors 9 , 10 , 11 , 12 that is always optimal for the particular application, and such that drive wheels 19 , 20 , 24 , 25 may be prevented from slipping.
To prevent and detect slip, one option is to use one or more slip sensors (not shown), e.g., a wheel sensor, installed in the machine itself. The wheel sensors measure the actual ground speed of the vehicle and detect—in combination with the rotational speed of at least one wheel 19 , 20 , 24 , 25 —slip at at least one wheel 19 , 20 , 24 , 25 , or they control drive wheels 19 , 20 , 24 , 25 directly and automatically intervene in control device 26 when slip occurs. The result of the intervention in control device 26 is that performance curve 49 is modified and the torque requirement is shifted. If slip occurs, the intake volume requirement is shifted downward briefly, thereby resulting in a reduction in wheel torque and, therefore slip. When drive wheels 19 , 20 , 24 , 25 are engaged with the ground once more, the torque requirement is raised again. The radar sensors are therefore used by control device 26 to regulate drive motors 9 , 10 , 11 , 12 . The devices known from the related art, i.e., ABS, VDC, TCS, ASR, and ESP may also be incorporated, of course, in the electronic control for the drive unit of the vehicle that is equipped according to the present invention.
Hydraulic motor 9 is absent form a further, simplified embodiment, which is based on the principle depicted in FIG. 2 . Harvesting machine 1 is driven hydraulically and directly at front axle 16 using differential gear 53 , via a mechanical main drive 2 , or via transmission 4 located between main engine 2 and differential gear 53 at front wheels 19 , 20 or the driven guide wheels of a track roller unit. Rear wheels 24 , 25 , which are located on controlled rear axle 21 , are driven according to the present invention by hydrostatic wheel hub motors 55 , which are driven based on a predetermined intake volume. Rear wheels 24 , 25 are preferably mounted on a rigid swing axle, which allows rear axle 21 to oscillate transversely to the direction of travel of harvesting machine 1 .
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.
While the invention has been illustrated and described as embodied in an electronic control for the drive unit of a vehicle, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | In vehicles designed to pick up and process crops, drive units affect the ground drive, which is an all-wheel drive, which acts on all of the wheels and/or track roller unit in contact with the ground, electronic controls and actuators perform the control and regulation of the drive units, and control units that control the drive torque at the wheels are used to obtain good traction and minimal slippage of the wheels on the ground. To control the drive torques, sensors are used at particular points, the signals and data of which are processed by the control device in order to predetermine a torque or intake volume requirement. The preselection of torque in the control results in the intake volume of the hydraulic drive motor being regulated. By specifying the intake volume required, it is possible to obtain optimal traction at one or more drive wheels, and to prevent undesired slippage of any one drive wheel in advance. | 5 |
BACKGROUND
This invention relates generally to media sharing, and more particularly, to a framework and tools for sharing media content across a set of broadcast operation centers.
Sharing of media content across a set of broadcast operation centers has typically been addressed by manually checking what media is needed at each site or location independently. Further, known solutions such as those systems that employ a central database or central server undesirably lend themselves to a single point of system failure and require all sites to be known a-priori.
It would be desirable to provide a system and method of media sharing across a set of broadcast operation centers that overcomes the foregoing disadvantages. The system and method of media sharing should provide a global view of media asset needs and provide automated movement of content where it is needed to allow content to be shared among any peer in the participating network while eliminating the possibility of a single-point of system failure.
BRIEF DESCRIPTION
Briefly, in accordance with one embodiment, a media sharing system comprises a plurality of broadcast operation centers configured to automatically acquire and distribute media content among one another based upon the media content needs and inventories of each participating broadcast operation center, the media sharing system being further configured to eliminate any single-point of system failure such that an inventory of media content corresponding to a particular broadcast operation center remains available to broadcast operation centers remaining on the media content sharing system subsequent to failure of the particular broadcast operation center.
According to another embodiment, a method of sharing media content between a plurality of broadcast operation centers for a corresponding media content sharing system comprises automatically acquiring and distributing media content among the broadcast operation centers based upon the media content needs and inventories of each participating broadcast operation center to eliminate any single-point of media content sharing system failure, such that an inventory of media content corresponding to a particular broadcast operation center remains available to broadcast operation centers remaining on the media content sharing system subsequent to failure of the particular broadcast operation center.
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 simplified block diagram illustrating a media broker process according to one embodiment; and
FIG. 2 is a simplified block diagram illustrating a more detailed media broker process for the system depicted in FIG. 1 ;
FIG. 3 is a simplified block diagram illustrating a media broker processing chain according to one embodiment;
FIG. 4 illustrates an overlay system optimizer according to one embodiment; and
FIG. 5 is a simplified diagram illustrating one embodiment of a network topology associated with the media broker system depicted in FIGS. 1 and 2 .
While the above-identified drawing figures set forth alternative embodiments, other embodiments of the present invention are also contemplated, as noted in the discussion. In all cases, this disclosure presents illustrated embodiments of the present invention by way of representation and not limitation. Numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of this invention.
DETAILED DESCRIPTION
FIG. 1 is a simplified block diagram illustrating a media broker system 10 according to one embodiment. Media broker system 10 includes three media broker sites including site A 12 , site B 14 , and site C 16 . The number of media broker sites shown is exemplary and any number of media broker sites may be included in the media broker system 10 depending on the particular application.
Media broker system 10 , according to one embodiment, operates when site A 12 broadcasts a request for media content over a set of distribution channels, i.e., standard definition, high definition, over the air, internet, etc. Typically, within the broadcast operation center domain, each center is viewed as a silo with regard to acquisition and distribution of media content. Content to be distributed by one center must be ingested locally. Media broker system 10 provides a global view of media assets and facilitates the automatic sharing of media across all sites within the system.
More particularly, media broker system 10 comprises an overlay network, described in further detail below, including optimizers such as that depicted in FIG. 4 running at each node 12 , 14 , and 16 . Content needs for a particular site such as described above for site A 12 are broadcast over this network 18 to see which sites can satisfy the media request. Further, the peer sites, such as sites B 14 and C 16 , broadcast their inventories of media content over network 18 . The requisite optimizer corresponding to the requesting site then determines which site should satisfy the content in cases where multiple sources are found. In this manner, media broker system 10 also facilitates automatic content movement to disaster recovery sites as well as provides third parties with the ability to supply content.
The overlay network provides a global view of media asset needs and provides automated movement of content to where it is needed. This solution allows content to be shared among any peer participating in the network. A single point of system failure is eliminated since the media broker system 10 neither requires or includes a central database that could otherwise cause the system to fail along with failure of the central database. Media broker system 10 thus operates by automatically sharing media content across a set of broadcast operation centers 12 , 14 , 16 without the need to manually check what media is needed at each site or location, independently in a manner required with present techniques for sharing media content across a set of broadcast operation centers. Media broker system 10 advantageously also operates by automatically sharing of media content across a set of broadcast operation centers 12 , 14 , 16 without requiring that each site be identified a-priori; and peer sites may drop off the system 10 and/or new sites may automatically appear in the system 10 in random fashion with substantially no impact on system operability.
FIG. 2 is a simplified block diagram illustrating a more detailed view of media broker system 10 depicted in FIG. 1 . Media broker system 10 provides a global view of its media inventories and needed media assets over all participating broadcast domains. This is accomplished by having each member site (peer) participating in the network 18 to register with each other. According to one embodiment, all asset needs are broadcast to each member peer via, for example, a web service such as API. Any peers capable of satisfying the request respond positively and determine the best method to transfer the content based on their attributes. According to one aspect, each media broker site optimizer analyzes any received media content and processes the received media content if necessary to ensure the received media content is transferred in a format that is recognizable and workable via the corresponding media broker site.
FIG. 3 is a simplified block diagram illustrating a media broker processing chain 20 according to one embodiment. Each media broker 22 participating on the network 18 receives the media content needs 24 and haves (inventories) 26 of each peer media broker participating on the network. This is accomplished, as stated above, by having each member (peer) participating in the network to register with one another. Any peers 28 capable of satisfying a request respond positively and determine the best method to transfer the content based on their attributes. This communication structure provides an automated way to notify each participating media broker 22 about changing needs and haves. Media source tables, local to each peer, if used, can be updated by adding and/or removing media content sources from the table.
A transfer manager 30 functions to determine the best partner site 32 from among the possible sources 28 to serve as a source for a required piece of content. Once possible source(s) 32 are identified, they are entered into a transfer schedule 34 ; and a transfer agent 36 functions to generate and transmit transfer commands 38 to requisite transfer hardware elements and devices.
This communication structure reduces duplication of media content sharing efforts since only a single ingest location and quality control pass is required across the set of broadcast centers participating in the media broker system 10 . Since media content can now be shared through participating peers in the overlay network, the media asset only needs to be ingested once.
As used herein, the term content is used to uniquely identify a specific piece of media. The term Site represents a site which either ingests, archives, and/or plays out content. The term peers signifies a subset of sites which can participate in communications with Site. The term needs represents content required by Site. The term availability denotes content available at Site. The term possible sources represents a subset of sites which can provide the needed content. The term media locator is a system which identifies the set of peers within the network that can provide the required content. The term transfer manager is a system(s) which is/are used to calculate the transfer schedule based on requirements of participating Sites. The term transfer agent is a system(s) which is/are interact with required external hardware to execute the desired or requisite transfer schedule.
According to one aspect, the transfer manager comprises a transfer cost model that may be an optimizer such as depicted in FIG. 4 to generate the transfer schedule. The cost model is specific to a particular set of wants and needs and may be specific, for example, to a particular end user or application. The cost model may, for example, generate the transfer schedule in response to, without limitation, needed time, available bandwidth, required bandwidth, and/or content type.
FIG. 4 illustrates a media broker cost optimizer 40 used by the transfer manager to determine an appropriate transfer schedule according to one embodiment. Three n-tuples are constructed representing to determine the near optimal cost for a specific piece of media content. These n-tuples are constructed to represent the requisite or desired parameter values, transfer functions and weighting constraints respectively for each parameter to be evaluated by the cost optimizer. These n-tuples may be represented, for example, as Parameter values: <P 1 , . . . , P n >; Transfer functions: <f 1 (P 1 ), . . . , f n (P n )>; and Parameter weights: <W 1 , . . . , W n > based on a given cost optimizer consisting of n parameters.
The transfer manager is responsible for the actual transfer of content from a remote site to a local site hosting the transfer manager. The content is selected based on a cost optimizer which uses a set of parameters to determine a near optimal transfer schedule, i.e., on-air-time/time-to broadcast, file format, available link bandwidth, required link bandwidth, and content type.
An available bandwidth parameter may be, for example, 500 Mb/s. The transfer function is a parameter specific function which translates the corresponding parameters into numeric values such that higher values indicate a better value according to one embodiment. A weighting factor adjusts the importance of each value in a range from about 0.0 to 1.0 according to one embodiment.
FIG. 4 illustrates operation of a transfer manager cost optimizer 40 according to one embodiment in which P 1 represents on-air-time/time-to-broadcast and is weighted at 50%, P 2 represents available link bandwidth and is weighted at 30%, and P 3 represents content type and is weighted at 20%. A first sample content score C 1 is determined to be 424.9 while a second sample content score C 2 is determined to be 620. Since the value of C 2 is higher than the value of C 1 , the second sample content is transferred by the transfer manager ahead of the first sample content.
FIG. 5 is a simplified diagram illustrating one embodiment of a network topology 60 associated with media broker system 10 . Each site 12 , 14 , 16 is connected to every other site through a dedicated communication link. Each site has a schedule of content to be broadcast (S i ) and a list of required content which is not accessible locally (M i ).
Automated media content distribution is accomplished via the overlay network which determines which peers can supply needed content for a given peer. Peers requiring media assets determine which data source should supply the content based on a cost function, as discussed above. This cost function uses several attributes in its determination including, without limitation, time requirements, file format requirements, network requirements, and so on.
The media broker embodiments described herein advantageously allow a single place to view content needs across an entire broadcast domain while reducing duplication of efforts for ingestion of required media. The communication structure automatically distributes content to sites where it is needed while determining the lowest cost source of media. The communication structure further eliminates any central point of communication system failure such that peers may dynamically enter and exit the overlay network to share local and global media content, regardless of whether any broadcast operation center from a plurality of broadcast operation centers on the media content sharing system experiences a communication failure. This feature also provides for multiple broadcast operation center failures on a media content sharing system with more than three broadcast operation centers.
Further, peers need not be specified a priori and may register, for example, at run-time. Only one peer in the current network is required to be known beyond the dynamically entering or exiting peer.
Although a central server could be employed to provide a media content sharing network, such a communication structure disadvantageously introduces a single-point of system failure that shuts down the entire network or otherwise causes the communication network to malfunction.
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 media content sharing system includes multiple broadcast operation centers that together are configured to automatically acquire and distribute media content among one another based upon the media content needs and inventories of each participating broadcast operation center. The media sharing system architecture eliminates any single-point of system failure such that an inventory of media content corresponding to a particular broadcast operation center remains available to broadcast operation centers remaining on the media content sharing system subsequent to failure of the particular broadcast operation center. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to the formation of an environmental seal around objects such as telecommunications and other cables.
Splicing of cables requires removal of cable jackets in order to expose the underlying conductors for connection. Once the conductors have been connected some sort of seal must be built up across the splice, effectively replacing the removed jacket, in order to protect the otherwise exposed conductors from the environment. The resulting seal, known as a splice case, should have a life-time comparable to that of the cables themselves, commonly 20 or so years. In addition to protecting the conductors from moisture and other environmental contaminants, the splice case must provide some mechanical protection, such as axial pull strength, so that any stresses on the cables are not taken up by the conductor connections. Some cables are pressurized in order to prevent ingress of moisture or to provide a means for detecting and locating leaks, and splice cases joining such cables must, in general, be resistant to pressure-induced creep over their desired life-time. Splice cases must often be installed under unfavourable outdoor conditions and installation must therefore be simple and quick.
It can be seen from these requirements that design of a splice case is not a trivial matter. In recent years heat-shrinkable sleeves, internally coated with a hot melt adhesive, have become widely used for protecting cable splices. They are quick and easy to install and provide the desired environmental and mechanical protection. However, they generally require the use of an open-flame torch for installation which is discouraged in some locations and prohibited in others.
Alternative techniques for forming a seal around cables are disclosed in WO 92/19034 (Raychem), the disclosure of which is incorporated herein by reference. That patent application discloses a flexible hollow sealing member, or bladder, that can be inflated to seal the gap between first and second articles, such as a cable and a duct or splice case housing, and that has a hole directly through a wall or between walls thereof through which hole a tube can be inserted to introduce a pressurizing gas. When the tube is removed the hole is automatically sealed by an internal gel-coated flap. The bladder may be wrapped around the cable to be sealed and then slid along the cable into the duct or splice case housing, and then inflated.
Surprisingly, this technique has been found to be suitable for forming seals having the desired life-time. A difficulty can however arise where the housing, be it a duct or a splice case, is of the so-called wraparound type. This term is well known in the art and means simply that the housing can be installed around an intermediate portion of the cable without access to a free end of the cable. Such a housing will therefore be split, and may comprise two or more "half" shells. The problem arises because the split between the parts of the housing must be sealed if it is not to provide a leak path into the resulting splice case.
Such a split housing may comprise a split or wraparound sleeve that is supported at its ends by disc-shaped end plates. A seal must therefore be made circumferentially around each end plate to the overlying sleeve and also along the longitudinal split in the sleeve. Where these two seals meet is called a triple point and the problem of sealing it has been addressed in U.S. Pat. No. 4,845,314 (Siemens). That patent discloses a cable seal with a wraparound sleeve engaging a pair of split end plates having a sealing system including ring seals on the end plates and a longitudinal sealing element for the slit in the wraparound sleeve. The longitudinal edges of the sleeve have a groove receiving the seal with an inner wall of the groove in the region of the ring seals having a lateral opening or window through which a portion of the longitudinal sealing member can extend to contact the ring seals. Note, however, that no discussion is made of any seal between the ring seals and the underlying split end plates.
SUMMARY OF THE INVENTION
We have now discovered that a split housing accommodating an inflatable bladder can be designed in such a way that the split is sealed.
Thus, the present invention provides a device for forming an environmental seal around an object such as a cable, which comprises:
(a) a split housing having a chamber that can surround the object;
(b) an inflatable bladder that can be inflated around the object and within the chamber;
the housing having a window breaking through its split such that the bladder can seal to a seal outside the chamber.
The bladder may be of any suitable shape or design but is preferably substantially as described in WO92/19034, and in particular preferably has a sealing material such as a gel overlain by a flap on an internal surface of a wall thereof for self-sealing of a hole through the wall after inflation of the bladder. Inflation may be carried out by inserting a tube through the wall of the bladder either before or after the bladder has been positioned within the housing.
Where the device is for forming a branched cable splice, the housing will have means for accommodating two or more cables substantially side-by-side. This may be done by providing two or more chambers and an inflatable bladder for each. The window may then break through a wall of the housing from one chamber to the other such that the two bladders can seal to one another. The seal between the bladders may of course be via some further sealing member, such as a coating or layer provided on one or both bladders.
Additionally or alternatively the window may allow the or each bladder to form a seal to a casing that surrounds the housing. In this case the window may break through to an external surface of the housing. Here, the housing may serve as an end part to a splice case, providing a seal to incoming cables. The splice itself may then be housed in the casing which may be a sleeve that extends away from the housing. In the case of a butt splice case one housing will be provided and the casing will comprise a blind or dome-shaped, tube. Alternatively, an in-line splice case may be provided in which case a housing will be provided at each end of a casing. In general, the casing will comprise a sleeve, an end portion of which overlaps and is supported by the housing.
A seal may be made directly between the casing and the housing that it overlaps, but in some cases it may be preferred to provide some additional seal between them such as an O-ring or other circular seal. Such a circular seal will generally be truly circular (since the housing around which it is to seal will generally be truly circular), but it can have other shapes and by "circular" we simply mean that in use the seal forms a closed loop. The seal may, however, be supplied in "wraparound" form and therefore comprise a length of sealing material whose ends can be brought together. The seal is preferably an O-ring of oval or substantially truly circular cross-section. Where a circular seal is to be used the housing may be provided with a seal for it around its periphery. Such a seal may serve to retain the seal in its desired location and may comprise a circumferentially-extending recess having a depth less than the thickness of the seal in order that the seal protrude above it for contact with an overlying casing. The window will then in general break through to the base of the seal for the circular seal in order that the circular seal can form a seal between the casing and the bladder.
The casing may comprise a wraparound sleeve having a sealing material sealing along a longitudinal split thereof, and having its own window that breaks through its split to an internal surface of the sleeve to make a seal to the circular seal. Thus a wraparound sleeve of the type disclosed in U.S. Pat. No. 4,845,314 may be used.
The device of the invention may be provided with a clamp for mechanically attaching the cable or other object to the housing. Such a clamp may provide axial pull strength or other reinforcement.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is further illustrated with reference to the accompanying drawings, in which:
FIGS. 1A and 1B show prior art use of an inflatable bladder;
FIGS. 2A and 2B show a prior art solution to the triple point problem;
FIG. 3 shows a housing as used in the invention;
FIG. 4 shows a part of housing;
FIG. 5 shows an inflatable bladder installed in a housing;
FIGS. 6A 6B and 6C show housings for sealing various cable configurations.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1A and 1B show inflatable bladders as disclosed in WO92/19034. In FIG. 1 an inflatable bladder 1 is shown as a duct seal, sealing an annular gap between a cable 2 and a duct 3. The bladder could however be used inside a casing in order to form a splice case. The bladder 1 has flexible and preferably substantially non-stretchable, walls 4 between which a pressurizing fluid such as air is introduced. An outer surface of the walls 4 may be provided with a sealing material 6, such as a mastic, to fill irregularities in the surface of the duct or outer casing. The bladder 1 is shown in more detail in FIG. 1B, where a relief layer or thin film 7 is provided over the mastic 6, either in order to protect it before use or to provide a lower friction surface to facilitate installation of the bladder. The bladder has a sealing gel 8 overlain by a flap on an internal wall for self-sealing a hole through the wall after inflation of the bladder and removal of an inflating tube 9.
A solution to the triple point problem as disclosed in U.S. Pat. No. 4,845,314 is illustrated in FIGS. 2A and 2B. A splice case 10 is formed around a cable 11 (partially drawn) and comprises split end plates 12, the split 13 allowing the plates to be "wrapped around" the cables. A wraparound casing 14 is then installed around the end plates and the longitudinal edges 15 fastened together. A longitudinal seal 16 provides a seal between edges 15. The sleeve 14 can be seen in FIG. 2B to have a window 17 breaking through its internal surface such that longitudinal seal 16 is able to contact an O-ring 18 that surrounds each end plate 12.
A housing 19 as used in the invention is shown in FIG. 3. The housing comprises parts 20 that abut one another at a split plane 21. The housing shown in FIG. 3 is designed to form an outlet for a splice case: the cables enter the splice case through the two inlets shown at the left-hand side of the figure, and the splice itself is sealed at a position to the right of the figure and within a casing (not shown) that extends from a mid point of the casing to the right as drawn.
The casing shown in FIG. 3 is for sealing two ingoing cables, and as a result has first and second chambers 22 and 23 into which inflatable bladders can be positioned as shown in FIG. 1A. The housing 19 has a window 24 which breaks through to an external surface of the housing such that a bladder within the chamber 22 can contact a casing surrounding the housing. Two such windows 24 may be provided at the split plane 21, one at each side of the housing. A further window 25 is also shown which breaks through from one chamber to the other, again at the split plane 21. This window 25 allows a bladder in chamber 22 to seal to a bladder in chamber 23.
The thickness of the wall of the housing that defines each window has preferably substantially zero thickness at the window. The wall need not of course terminate as a sharp edge and it may be slightly rounded, but there is preferably no significant flat surface extending perpendicularly to the surface of the installed bladder at the window. This tapering or other shaping of the wall of the housing at the window will facilitate a seal being made between two adjacent bladders or between a bladder and some other sealing member.
The window 24 breaks into the base of a seat 26 for a circular seal. The seat 26 preferably comprises a circumferentially-extending recess which can locate a circular seal around the periphery of the housing and which has a depth less than the thickness of the seal so that the seal protrudes above it. In this way, a casing surrounding the housing 19 will contact the circular seal. Where a splice case is to be constructed comprising two housings 19 bridged by a central casing, the two housings 19 may be mechanically interconnected by one or more tie bars 27. Also, a clamp may be provided for mechanically attaching to the housing 19 the cables that enter the cavities 22 and 23. Any axial stress on the cables will therefore be transmitted via such clamps to the housing and then from one housing to the opposite housing via tie bars 27. As a result, connectors interconnecting conductors of the cables will not be stressed.
FIG. 4 shows in greater detail a housing part 20 of slightly different design to that of FIG. 3. Windows 24 and 25 can be seen breaking through from the chambers 22, 23 to an external surface of the housing part and also from one chamber to the other. The walls of a housing part can be seen to taper to substantially zero thickness at the windows.
FIG. 5 is a partial plan view of the housing part of FIG. 4 shown with a cable 2A and bladder 28 in chamber 23 and with a cable 2B and bladder 29 in chamber 22. Also shown is a part of a casing 30 surrounding the housing and being sealed to it by means of an O-ring 32 which makes a seal through window 24 to bladder 28. Bladders 28 and 29 can be seen to be sealed to one another through window 25. Circular bands 31 surround the housing parts to hold them together.
FIGS. 6A, 6B and 6C show in end views various designs of housing. In FIG. 6A two chambers are provided with first windows 24 breaking into an external surface of the housing and with a second window 25 breaking from one chamber to the other. In FIG. 6B three chambers 22, 23 and 33 are shown side-by-side. In FIG. 6C three chambers 22, 23 and 33 are arranged at the corners of a triangle. This arrangement allows chambers to be provided that are larger than that allowed by the arrangement of FIG. 6A but it has the disadvantage that the housing is formed of three rather than two parts. Nonetheless, the various splits between the parts of the housing can still be sealed by providing appropriate windows 25. | A device for forming an environmental seal around an object includes:
(a) a split housing having a chamber that can surround the object;
(b) an inflatable bladder for inflating around the object and within the chamber;
the housing having a window breaking through its split so that the bladder seals to a seal outside the chamber. | 7 |
This application is a continuation-in-part of application Ser. No. 09/034,157 filed on Mar. 2, 1998, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a construction block having good insulation and fault-tolerant properties.
2. Background of the Prior Art
Construction blocks are typically but not necessarily rectangular members having a pair of faces joined by four sides. These blocks, which are use to build partition structures, are usually transparent or translucent and may have a texture pattern on the faces. The outer surface of the blocks may be smooth or may have an appropriate mechanism for joining the block to other blocks. U.S. Pat. No. 5,595,033 to Frey, U.S. Pat. No. 5,588,271 to Pitchford and my U.S. patent application Ser. No. 08/603,460 filed Feb. 20, 1996 are examples of such mechanisms. The blocks, which are made from glass, plastic or a similar material, are typically formed as two generally identical halves welded together forming a seam.
These construction blocks, which enjoy wide popularity in the construction industry, have several areas that can benefit from improvement. Although, modern construction blocks have a relatively high level of thermal insulation and sound insulation capability, these levels can always withstand being raised. Another problem with present construction blocks is found in seam failure. A small hole along the seam not only reduces the insulation properties of that block but also serves as in introduction point for moisture to enter the interior chamber of the block. The moisture within the block condenses and becomes unsightly. The moisture introduction is exacerbated by the bellowing effect created by the block due to the difference in temperature between the block face on the interior of the building and the temperature of the block face on the exterior of the building.
Therefore, there is a need in the art for a construction block that addresses the aforementioned shortcomings of the present-day blocks. Such a construction block must have improved thermal properties and must limit the adverse effects of a failed seam.
SUMMARY OF THE INVENTION
The construction block of the present invention addresses the aforementioned needs in the art. The construction block increases the thermal efficiency and sound insulation of the block. The construction block also attacks the moisture problem experienced from a failed seam by outright eliminating the condensation within the interior chamber of the block or by isolating the condensation from the sight of a user. The bellowing effect—which tends to pull air from the exterior of the block into the interior chamber of the block through the pinhole—created by the block is also reduced. A method of increasing the thermal efficiency or eliminating the condensation is also disclosed.
The construction block of the present invention is comprised of a body having a pair of faces joined by a plurality of side edges, each having an inner surface and an outer surface, defining an interior chamber. The body of the construction block is formed from two similar half bodies joined, in airtight fashion, along a seam.
Means for joining the construction block with other construction blocks, may but need not be provided.
An appropriate desiccant, an insulation gas or both are disposed within the interior chamber of the construction block. The desiccant lies at the bottom of the construction block out of sight of a user. At least one opening can be provided on the block for introduction of the desiccant or insulation gas, the opening being airtight sealed after introduction. Alternately, at least one weakened area, which may or not be perforated, may be provided on the construction block. The weakened area can be punched by a screwdriver or similar instrument for creating the opening. A locator mark can be provided on the block in the area defined by the weakened area for easy and consistent location of the weakened area. Alternately, the locator mark can be provided on the block (without the block having a weakened area) so that a person can drill an opening at the locator mark. The opening, weakened area, or locator mark can be located on at least one of the faces, on at least one of the sides or both. By providing these members on the side of the block, the sealed opening will not be visible to a user.
At least one baffle is disposed within the interior chamber. The baffle, which is a generally planar member may but need not have at least one opening located thereon. The at least one opening allows any introduced insulation gas to fill the entire construction block as opposed to only a portion of it. The baffle may be friction held in position or may have its outer periphery tapered to meet the taper of the taper of at least one of the inner surfaces. A second taper on the baffle (or the first taper if not used for positioning) may serve as a trough for receiving a sealant to airtight seal the baffle into place along the baffle's outer periphery. A retainer may be used for holding the baffle in place. The retainer may be in the form of a continuous groove or may be a bump, a ridge, or a one-way ramp. The bump, ridge or one-way ramp may be one continues member or may be a series of discrete members. The baffle is inserted into the interior chamber until it is pushed into the retainer in the case of the groove, or otherwise past the retainer. A second retainer or series of retainers may be provided beyond the baffle for sandwiching the baffle therebetween.
The baffle may have an appropriate optical coating thereon.
The baffle serves several important roles. The baffle adds additional thermal insulation capacity and sound insulation capacity to the construction block. The baffle reduces the bellow effects created by the inner positioned face and the outer positioned face. The baffle separates the interior chamber into two or more sub-chambers. For example, by placing two baffles into the interior chamber, one baffle on one side of the seam and the other baffle on the other side of the seam, the interior chamber is separated into three sub-chambers. Therefore, any moisture and the resulting condensation that is introduced into the construction block through a failure in the seam is isolated within the middle sub-chamber out of sight of a user. Lastly, the baffles may be used to add to the overall aesthetic qualities of the block by coming in different colors, patterns including light diffusing patterns, smoked appearance, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view, partially sectioned for clarity, of the construction block of the present invention.
FIG. 2 is a close-up view of one of the corners of the construction block.
FIG. 3 is a perspective view of the baffle.
FIG. 4 is a cross-section view of the baffle seated within an inner surface of the construction block.
FIG. 4A is a close-up of a portion of FIG. 4 .
FIGS. 5-8 illustrate in cross-section, the various retainers that may be used to hold the baffle within the construction block.
Similar reference numerals refer to similar parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, it is seen that the construction block of the present invention, generally denoted by reference numeral 10 , is comprised of a generally rectangular body having a pair of face 12 joined by four side edges 14 , each having an inner surface and an outer surface, defining an interior chamber. The body is formed from two similar halves that are joined, in airtight fashion, along a seam 16 . The airtight joiner of the two halves can be accomplished in appropriate fashion such as using an appropriate adhesive along the seam 16 , ultrasonically welding the two halves along the seam 16 , etc. It is expressly understood that the construction block 10 can be constructed in a shape other than rectangular, and having other than four sides, in keeping within the scope and spirit of the present invention. The outer surface of the construction block 10 can be generally smooth, or can have any appropriate structure for joining the construction block 10 to other construction blocks 10 . The faces 12 of the construction block 10 can be transparent, translucent, or opaque. The faces 12 may also have an appropriate textured surface, such as a wave pattern, column pattern, etc., if desired. The construction block 10 body is formed from an appropriate resin material, such as acrylic.
Disposed within the interior chamber of the construction block 10 is an appropriate desiccant for absorbing any moisture within the interior chamber. As the desiccant will fall to the bottom of the interior chamber, it will not be readily visible even in a construction block 10 having transparent faces 12 . Alternately, or in addition to the desiccant, an insulation gas may be disposed within the interior chamber. The insulation gas is chosen from the group consisting of argon, krypton, xenon, or combinations thereof or any other insulating gas or combination thereof.
In order to introduce the desiccant or insulation gas into the interior chamber, the construction block 10 may be formed with at least one opening 18 located thereon, as illustrated in FIG. 1 . The opening 18 can be located on at least one of the faces 12 , on at least one of the sides 14 or both. After the desiccant or insulation gas is introduced into the interior chamber, each opening 18 is sealed airtight in any appropriate fashion. Alternately, at least one weakened portion can be provided on at least one of the faces 12 , on at least one of the side edges 14 , or both. The weakened portion may be punched out with a screwdriver, drill or other similar tool and the desiccant or insulation gas introduced through the opening thus created. Again, after the desiccant or insulation gas is introduced into the interior chamber, each opening is airtight sealed in any appropriate fashion. A locator mark 20 can be provided on the area encompassed by the weakened portion for easy location of the weakened area. Alternately, a locator mark 20 may be provided on any appropriate portion of the construction block 10 so that the area identified by the locator mark 20 may be drilled to provide a consistent location for the opening for introduction of the desiccant or insulation gas. Again, after the desiccant or insulation gas is introduced into the interior chamber, each opening is airtight sealed in any appropriate fashion.
As seen in FIGS. 1 and 3 - 8 , at least one baffle 22 can be disposed within the interior chamber. The baffle 22 is a generally planar member having an outer periphery and is in a shape generally similar to the shape of the interior chamber defined by the side edges 14 . At least one opening 24 can be located on the baffle 22 . The baffle 22 may be formed directly with the construction block 10 . Alternately, the baffle 22 may be a separate member that is inserted into the appropriate position within the interior chamber. The baffle 22 may be friction held in place, and, if desired, airtight sealed into place by an appropriate sealant 26 . The outer periphery of the baffle 22 may have a first taper 28 and the inner surface of at least one side edge 14 may also have a complimentary taper for receiving the first taper 28 . A second taper 30 (this may be the only taper if the first taper 28 is not used) may be located on the outer periphery of the baffle opposite the first taper 28 , this second taper 30 is used as a trough for receiving the sealant 26 .
As seen in FIGS. 5-8, a retainer can be used for holding the baffle 22 in place. The retainer can be of any desired construction including the groove 32 illustrated in FIG. 5, the at least one hemispheric bump 34 illustrated in FIG. 6, the at least one ridge 36 illustrated in FIG. 7, or the at least one one-way ramp 38 illustrated in FIG. 8 . The retainer can be one continuous member as seen in FIG. 7 or can be a series of discrete members as seen in FIGS. 6 and 8. The groove 32 must be a continuous member on each side edge 14 on which it is located. The baffle 22 is inserted into place until it is received within the retainer in the case of the groove 32 or until it passes the first retainer or series of retainers. Furthermore, a second one or second series of at least one bumps 34 , ridges 36 , or one way ramps 38 can, but need not be provided on the opposite side of the baffle 22 to hold the baffle sandwiched between the two series of retainers.
Each baffle 22 can be provided with an optical coating on one or both surfaces. This coating can be used to control the effects of the sun, such as an ultraviolet light barrier coating or can be a visual coating, such as a tint, a color, or a reflective surface in order to change the overall appearance created by the construction block 10 . By placing the coating on the baffle 22 as opposed to one or both of the faces 12 of the construction block 10 , the manufacturing costs tend to be reduced and the coating, which tends to be soft, is safely sealed within interior of the construction block 10 so that it cannot be scratched or otherwise tampered.
While the invention has been particularly shown and described with reference to an embodiment thereof, it will be appreciated by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention. | A construction block has improved thermal insulation qualities and reduces or outright eliminates the effects of a seam failure. The construction block is comprised of a pair of generally parallel faces joined by a plurality of sides. A desiccant or insulation gas, or both are disposed within the interior chamber of the block. At least one baffle is disposed within the interior chamber. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This nonprovisional application claims priority under 35 U.S.C. §119(a) on Patent Application Nos. 2011-077424 and 2011-077426, filed in Japan on Mar. 31, 2011, respectively. The entirety of each of the above-identified applications is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a hydraulic tensioner that applies appropriate tension to an endless power transmitting member, such as an endless chain or an endless belt for the power transmission of a valve motion mechanism of an internal combustion engine.
[0004] The present invention also relates to leak oil emitting device for a hydraulic tensioner that applies tension to an endless power transmitting member configured from a chain, a belt or the like used in a valve motion of an internal combustion engine.
[0005] 2. Description of Background Art
[0006] An internal combustion engine incorporated in a vehicle such as a motorcycle includes a hydraulic tensioner for pressing an endless power transmitting member, which drives a camshaft of a valve motion mechanism in order to prevent flapping of the endless power transmitting member upon operation of the internal combustion engine.
[0007] A hydraulic tensioner is available, wherein a pressure maintaining valve for preventing a pressure drop in a high pressure oil chamber in the hydraulic tensioner in a state in which the oil supplying pressure drops upon stopping of operation of an internal combustion engine is provided in an oil supplying path (refer to, for example, Japanese Patent Laid-Open No. 2009-180359).
[0008] An internal combustion engine incorporated in a motorcycle or the like has an endless power transmitting member for driving a cam of a valve motion. In order to prevent flapping of the endless power transmitting member upon operation, the internal combustion engine includes a hydraulic tensioner for pressing the endless power transmitting member. As a conventional example, an example is available wherein the internal pressure of the hydraulic tensioner, which becomes a high pressure, is kept at an appropriate pressure by a gap appearing between a plunger made of a flexible material and a hollow sleeve fitted in the inside of the plunger, and leak oil is emitted from an emitting flow path provided in a housing (refer to, for example, Japanese Patent No. 3594420). However, since the oil entering the gap between an outer face of the plunger and a chamber wall face (plunger accommodating hole) cannot flow out quickly to the outside, movement of the plunger upon forward motion is suppressed, and the follow-up property for a movement of a tensioner slipper is deteriorated. However, if it is tried to carry out accuracy management of the gap over the overall contact area between the plunger outer face and the plunger accommodating hole, then since the accuracy management region is wide, the cost increases.
SUMMARY OF THE INVENTION
[0009] With the hydraulic tensioner disclosed in Japanese Patent Laid-Open No. 2009-180359, wherein a pressure maintaining valve is provided in an oil supplying path, by blocking the oil supplying path and an oil discharging path, also upon stopping of operation of the internal combustion engine, the oil pressure in the high pressure oil chamber can maintain a high level similarly as upon operation of the internal combustion engine. Also, upon re-starting of the internal combustion engine, the hydraulic tensioner can have an appropriate tensioning characteristic to the endless power transmitting member similarly as in the operation state of the internal combustion engine.
[0010] However, in order to obtain such a characteristic as just described, it is necessary to enhance the pressure resisting property and the sealing property of parts in the hydraulic tensioner, and there is the possibility that an increase of the cost may be provided.
[0011] The present invention relates to improvements in a hydraulic tensioner, which overcome such a defect as described above, and it is an object of the present invention to provide a hydraulic tensioner which can maintain an endless power transmitting belt in an appropriate tension state in whichever operation or stopping state an internal combustion engine is.
[0012] In order to achieve the object described above, according to an embodiment of the present invention, a hydraulic tensioner, includes a plunger, said plunger being acted upon by reactive force from an endless power transmitting belt; a plunger body cooperating with said plunger to form a high pressure oil chamber for storing pressure oil therein; a biasing device accommodated in said plunger, said biasing device being configured to push out said plunger toward said endless power transmitting belt; an oil supply path configured to supply oil into said high pressure oil chamber; a check valve configured to permit supply of the oil from said oil supply path into said high pressure oil chamber; a relief valve configured to communicate a relief path with an oil pressure higher than a predetermined oil pressure in said high pressure oil chamber; and a pressure maintaining valve interposed in said relief path for being opened and closed by the oil pressure of said oil supply path, wherein a path that is branched from said oil supply path for operating said pressure maintaining valve is formed independently of an oil supply path to said check valve.
[0013] According to an embodiment of the present invention, the hydraulic tensioner is configured such that the relief path and the oil supply path are in communication with each other by an oil supply pressure to the pressure maintaining valve.
[0014] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that the pressure maintaining valve is provided in a returning path in communication with the relief path and the oil supply path, and in the returning path, the valve body of the pressure maintaining valve is formed in a cylindrical shape and a top portion side circumferential face of the cylindrical valve body is formed with a reduced diameter.
[0015] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that a drain oil path in communication with the outside is provided in the plunger body, and the relief path and the drain oil path are in communication with each other by an oil supply pressure to the pressure maintaining valve.
[0016] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that the pressure maintaining valve is formed in a cylindrical shape, and a cylindrical portion top face upon which operating oil acts and an emission hole for emitting the operating oil to the drain oil path side are provided on a cylindrical portion side face such that the operating oil is emitted through the inside of the pressure maintaining valve.
[0017] According to a further aspect of the present invention, the hydraulic tensioner is configured such that the oil supply path is configured through the inside of a valve body which configures the relief valve, and oil is supplied from an end portion of the relief valve.
[0018] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that a holding plate for holding an end portion of a coil spring, which biases the relief valve, is disposed at a location of the oil supply path to which the oil is supplied from the end portion of the relief valve, and an oil introduction hole is provided in the holding plate.
[0019] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that the pressure maintaining valve is provided in a converging relief path to which the relief paths converge after being formed radially from a hydraulic cylinder.
[0020] The present invention also enhances the emission property of oil through a gap between an inner circumferential face of a plunger body and an outer circumferential face of a plunger to reduce the sliding resistance of the plunger by oil resistance thereby to smoothen the movement of the plunger.
[0021] The present invention solves the problem described above, and according to an embodiment of the present invention, the hydraulic tensioner further comprises a gap portion, through which oil in said high pressure oil chamber can flow out to the outside, is provided between an inner circumferential face of said plunger body and an outer circumferential face of said plunger, wherein a downstream side gap of said gap portion through which the oil flows out has an area greater than that of an upstream side gap of said gap portion.
[0022] According to an embodiment of the present invention, the hydraulic tensioner is configured such that inner and outer diameters and working tolerances are set such that a gap dimension where the dimension of the downstream side gap is formed smallest is greater than a gap dimension where the dimension of the upstream side gap is formed greatest.
[0023] According to an embodiment of the present invention, the hydraulic tensioner is configured such that an oil emitting groove is formed on a downstream side sliding face of the plunger body such that an upstream end thereof extends to the upstream side gap.
[0024] According to an embodiment of the present invention, the hydraulic tensioner is configured such that the plunger has a plunger stepped portion formed from a plunger large diameter portion on the upstream side and a plunger small diameter portion on the downstream side; the plunger body has a plunger accommodating hole stepped portion formed from a plunger accommodating hole large diameter portion corresponding to the plunger large diameter portion on the upstream side of the plunger and a plunger accommodating hole small diameter portion corresponding to the plunger small diameter portion of the plunger; the plunger stepped portion of the plunger engages with the plunger accommodating hole stepped portion of the plunger body to form a coming off preventing structure for the plunger; and the oil emitting groove is formed on the plunger accommodating hole small diameter portion such that an upstream end thereof extends to the plunger accommodating hole large diameter portion.
[0025] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that the oil emitting groove is formed by machining on the plunger accommodating hole small diameter portion from the downstream end side, and the tip of the working tool reaches the plunger accommodating hole large diameter portion.
[0026] According to an embodiment of the present invention, the hydraulic tensioner is configured such that the oil emitting groove is disposed at a position clear of the direction of movement of an endless timing chain.
[0027] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that, in a state in which the hydraulic tensioner is attached to a vehicle, the hydraulic tensioner is disposed such that an oil emission direction of the oil emitting groove is directed downwardly with respect to a horizontal direction.
[0028] According to a further embodiment of the present invention, the hydraulic tensioner is configured such that the oil emitting groove is provided in a pair at opposing positions with respect to the center line of a plunger accommodating hole of the plunger body.
[0029] In the hydraulic tensioner according to the present invention, the oil released from the high pressure oil chamber by the relief valve is filled only between the downstream of the check valve and the pressure maintaining valve in the relief path, and the pressure is maintained. Consequently, the pressure on the relief valve side becomes equal to the pressure in the oil supply path. Therefore, oil of a high pressure is not filled, and accordingly, a high sealing property is not required, and reduction of the cost can be anticipated.
[0030] With the hydraulic tensioner according to the present invention, in a state in which the pressure maintaining valve comes under oil pressure, since the relief path and the oil supply path are in communication with each other and oil is circulated, a state in which oil is always filled can be maintained, and consequently, the possibility of insufficient supply can be reduced.
[0031] With the hydraulic tensioner according to the present invention, the returning path can be configured in a simplified shape, wherein only part of the shape of the valve body of the pressure maintaining valve is modified.
[0032] With the hydraulic tensioner according to the present invention, since the amount of oil is not returned to the supply side, the oil pressure on the supply side is not raised and the necessity to enhance the sealing property is eliminated.
[0033] With the hydraulic tensioner according to the present invention, since the drain oil structure can be achieved utilizing the inside of the pressure maintaining valve, the path can be simplified.
[0034] With the hydraulic tensioner according to the present invention, the oil supply path can be configured utilizing the relief valve, and consequently, the path can be simplified.
[0035] With the hydraulic tensioner according to the present invention, the oil introduction hole is formed in the holding plate, and oil supply can be carried out smoothly.
[0036] With the hydraulic tensioner according to the present invention, since the pressure maintaining valve is disposed in the converging relief path, simplification of the path by the single pressure maintaining valve can be anticipated.
[0037] In an embodiment of the present invention, the area of the upstream side gap set for oil pressure adjustment is formed small while the area of the downstream side gap is formed greater than that of the upstream side gap. Consequently, the oil emission performance on the downstream side, which does not act for oil pressure adjustment, is enhanced thereby to reduce the sliding resistance of the plunger by oil resistance. Consequently, the movement of the plunger can be smoothened.
[0038] In an embodiment of the present invention, the inner and outer diameters and working tolerances are set such that the downstream side gap is greater with certainty than the upstream side gap. Consequently, the dimension management of the gaps can be made sure and the oil emitting property of the downstream side can be enhanced.
[0039] In an embodiment of the present invention, since the oil emitting groove is formed on the sliding face downstream side, the emitting performance of oil on the downstream side can be improved.
[0040] In an embodiment of the present invention, the oil emitting groove is formed on the plunger accommodating hole small diameter portion with which the plunger stepped portion of the plunger large diameter portion is engaged such that it extends to the plunger accommodating hole large diameter portion. Accordingly, the oil emission property of the plunger accommodating hole small diameter portion can be improved.
[0041] In an embodiment of the present invention, the oil emitting groove is formed by machining on the plunger accommodating hole small diameter portion from the downstream end side such that the tip thereof reaches the plunger accommodating hole large diameter portion. Accordingly, the oil emitting groove can be formed readily.
[0042] In an embodiment of the present invention, the oil emitting groove is disposed clear of the direction of movement of the endless timing chain. Consequently, when the plunger body vibrates upon movement of the endless timing chain, the plunger small diameter portion can be prevented from being damaged by an edge of the oil emitting groove.
[0043] In an embodiment of the present invention, the hydraulic tensioner is attached in the downward direction with respect to the horizontal direction to the vehicle. Consequently, in the state in which the hydraulic tensioner is attached to the vehicle, also emission is caused by the self weight of oil. Therefore, the oil can be emitted well.
[0044] In an embodiment of the present invention, the oil emitting grooves are disposed not at neighboring positions but are spaced away from each other at the opposing positions. Consequently, oil can be emitted well while suppressing a drop in strength of the plunger body.
[0045] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
[0047] FIG. 1 shows a hydraulic tensioner lift of an embodiment of the present invention and shows an example wherein the hydraulic tensioner is applied to a timing chain, which configures a power transmitting mechanism of a valve motion mechanism in a four-stroke cycle DOHC type internal combustion engine incorporated in a motorcycle;
[0048] FIG. 2 is a view as viewed in the direction indicated by an arrow mark II of FIG. 1 showing a shape of a cap of the hydraulic tensioner;
[0049] FIG. 3 is a rear elevational view of a tensioner body of the hydraulic tensioner as viewed in the direction indicated by the arrow mark II of FIG. 1
[0050] FIG. 4 is a vertical sectional view of the hydraulic tensioner taken along line IV-IV of FIG. 2 ;
[0051] FIG. 5 is a vertical sectional view of the hydraulic tensioner in a state in which a plunger projects forwardly from the tensioner body and a tension attaching portion of a cylinder head in FIG. 4 ;
[0052] FIG. 6 is a vertical sectional view of the hydraulic tensioner taken along line VI-VI of FIG. 2 ;
[0053] FIG. 7 is a fragmentary longitudinal sectional view of a check valve and a relief valve of the hydraulic tensioner;
[0054] FIG. 8 is a fragmentary longitudinal sectional view in a state in which the check valve and the relief valve of the hydraulic tensioner are assembled to a valve holder and a purge valve is assembled to the tensioner body while a pressure maintaining valve is disassembled;
[0055] FIG. 9 is a vertical sectional view of a hydraulic tensioner of another embodiment of the present invention and is a vertical sectional view taken along a plane similar to that of FIG. 4 ;
[0056] FIG. 10 is a vertical sectional view of the hydraulic tensioner of the embodiment shown in FIG. 9 and is a vertical sectional view taken along a plane similar to that of FIG. 5 ;
[0057] FIG. 11 is a right side elevational view of essential part illustrating a state in which an internal combustion engine including a hydraulic tensioner is attached to a vehicle body frame of a motorcycle;
[0058] FIG. 12 is a rear elevational view of the tensioner, particularly a view as viewed in the direction indicated by an arrow mark II of FIG. 11 ;
[0059] FIG. 13 is a view of a tensioner body as viewed from the rear;
[0060] FIG. 14 is a vertical sectional view taken along line IV-IV of FIG. 12 and is a longitudinal sectional view of the tensioner;
[0061] FIG. 15 is a fragmentary perspective view of a plunger, a valve holder, a check valve, a relief valve and so forth inserted in a plunger accommodating hole;
[0062] FIG. 16 is a view illustrating a disassembled state of a pressure maintaining valve and a purge valve;
[0063] FIG. 17 is a sectional view taken along line VII-VII of FIG. 12 ;
[0064] FIG. 18 is a view illustrating a state in which the pressure in an oil reserving chamber rises to project the plunger forwardly;
[0065] FIG. 19 is a partial enlarged view of a gap portion (between the plunger accommodating hole and the plunger) of FIG. 14 ;
[0066] FIG. 20 is a front elevational view of the tensioner body 20 ; and
[0067] FIG. 21 is a sectional view taken along line XI-XI of FIG. 20 ;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0068] The present invention will now be described with reference to the accompanying drawings wherein the same or similar elements will be identified by the same reference numeral.
[0069] In the following, a hydraulic tensioner 0 according to an embodiment of the present invention shown in FIGS. 1 to 8 is described.
[0070] FIG. 1 is a right side elevational view of an essential part illustrating a state in which an internal combustion engine 3 which includes the hydraulic tensioner 0 is attached to a vehicle body frame 1 of a motorcycle (which may otherwise be a road surface traveling vehicle such as an automobile).
[0071] In the present embodiment, forward and backward, upward and downward, and leftward and rightward directions signify the forward and backward, upward and downward, leftward and rightward directions of the vehicle body. In FIG. 1 , the forward and backward directions correspond to the rightward and leftward directions on the plane of the figure; the upward and downward directions correspond to the upward and downward directions on the plane of the figure; and the leftward and rightward directions correspond to the interior side direction and this side direction with respect to the plane of the figure, respectively.
[0072] As shown in FIG. 1 , the four-stroke cycle DOHC type internal combustion engine 3 , which includes the hydraulic tensioner 0 is incorporated in a motorcycle and has a particular structure that the internal combustion engine 3 is attached to a hanger 2 provided at a front portion of a vehicle body frame 1 of the motorcycle and a rear portion of the vehicle body frame 1 by two bosses 8 projecting from the internal combustion engine 3 .
[0073] In the internal combustion engine 3 , a cylinder block 5 , a cylinder head 6 and a head cover 7 are successively placed in order in the upward direction on a crankcase 4 and are coupled integrally by a coupling device such as bolts (not shown).
[0074] Further, an endless timing chain 13 extends between and around a driving sprocket wheel 10 , which is integrated with a crankshaft 9 supported for rotation, and a driven sprocket wheel 12 , which is integrated with a pair of camshafts 11 supported for rotation on the cylinder head 6 in the cylinder head 6 and the head cover 7 , at a position sandwiched between the crankcase 4 and the cylinder block 5 of the internal combustion engine 3 . Consequently, a rotating torque of the crankshaft 9 , which is driven to rotate in the clockwise direction in the figure by upward and downward movement of pistons (not shown) fitted for upward and downward sliding movement in cylinder bores (not shown) of the cylinder block 5 is transmitted to the paired camshafts 11 through the driving sprocket wheel 10 , endless timing chain 13 and driven sprocket wheel 12 so that intake and exhaust valves not shown are driven for opening and closing movement.
[0075] In the four-stroke cycle internal combustion engine 3 , a plurality of cylinder bores (not shown) are arrayed in the vehicle widthwise direction. In this internal combustion engine 3 , fuel in a combustion chamber burns in each of the cylinder bores every time the crankshaft 9 rotates twice, and the pistons are intermittently pushed toward the crankshaft 9 by pressure of the combustion gas. Further, since the traveling resistance varies in response to concaves and convexes of the road surface on which the motorcycle travels, the tension state of the endless timing chain 13 varies and the endless timing chain 13 is liable to flap in the forward and backward directions.
[0076] In order to prevent this, a chain guide 14 is disposed in contact with the endless timing chain 13 on the tension side on the front positioned rightwardly in FIG. 1 while a tensioner slipper 15 is disposed in contact with the endless timing chain 13 on the relax side on the rear positioned leftwardly in FIG. 1 . Further, the hydraulic tensioner 0 is assembled to the cylinder head 6 rearwardly of and adjacent to the tensioner slipper 15 . The hydraulic tensioner 0 has such a structure and a characteristic as hereinafter described in detail, and flapping of the endless timing chain 13 on the relax side can be suppressed effectively by the superior characteristic of the hydraulic tensioner 0 .
[0077] The shell of the hydraulic tensioner 0 shown in FIG. 1 is configured from a tensioner body 20 and a cap 21 . Bolts (not shown), which are fitted in a pair of left and right bolt fitting holes 21 a provided in the cap 21 shown in FIG. 2 , which is a view as viewed in the direction as indicated by an arrow mark II in FIG. 1 , extend through bolt fitting holes 20 b of the tensioner body 20 shown in FIG. 3 and are screwed in a lifter attaching portion 6 a of a rear portion of the cylinder head 6 to mount the hydraulic tensioner 0 integrally on the cylinder head 6 . As shown in FIGS. 4 to 6 , a plunger accommodating hole 20 a is formed in the tensioner body 20 , and a plunger 23 is accommodated for sliding movement in the plunger accommodating hole 20 a . Consequently, the tensioner body 20 plays a role as a plunger body.
[0078] Further, as shown in FIG. 3 , a packing fitting groove 20 d is formed on a rear end face 20 c of the tensioner body 20 in such a manner as to surround the plunger accommodating hole 20 a , and an annular packing 20 e is fitted in the packing fitting groove 20 d . As shown in FIGS. 4 to 6 , an oil reserving chamber 28 is configured from a rear end face 20 c formed on a front end face 21 b of the cap 21 and the rear end face 20 c of the tensioner body 20 .
[0079] Further, a base end portion 22 a of a valve holder 22 , formed in such a manner as shown in FIG. 7 , is fitted in a rear portion of the plunger accommodating hole 20 a of the tensioner body 20 as shown in FIGS. 4 to 6 , and the plunger 23 is fitted for forward and backward sliding movement in the plunger accommodating hole 20 a of the tensioner body 20 . Further, in a high pressure oil chamber 31 in the plunger accommodating hole 20 a and the plunger 23 , a coil spring 24 as a biasing device is interposed between a stepped front end face 22 b of the base end portion 22 a of the valve holder 22 and an inner face 23 b of a tip portion 23 a of the plunger 23 such that the plunger 23 is biased so as to project forwardly by spring restoring force of the coil spring 24 . It is to be noted that an abutting portion 23 c is mounted integrally at the tip portion 23 a of the plunger 23 .
[0080] Furthermore, a valve guide 25 a of a check valve 25 is fitted integrally at a front portion of a valve accommodating hole 22 c (refer to FIG. 7 ) formed at the base end portion 22 a of the valve holder 22 . A check valve coil spring 25 b and a spherical valve body 25 c are fitted in order in the forward direction from the rear on the valve guide 25 a.
[0081] Besides, a valve body 26 a of a relief valve 26 is fitted for sliding movement in the valve accommodating hole 22 c of the valve holder 22 , and in a valve chamber 26 b of the valve body 26 a of the relief valve 26 , a relief valve coil spring 26 d is interposed between a relief valve seat 27 disposed adjacent the cap 21 in the oil reserving chamber 28 and a tip portion 26 c of the valve body 26 a of the relief valve 26 . The oil reserving chamber 28 is connected to the high pressure oil chamber 31 through an opening 27 a of the relief valve seat 27 , relief valve 26 and check valve 25 .
[0082] A pressure maintaining valve 29 will now be described.
[0083] As shown in FIG. 3 in which the tensioner body 20 is viewed from the rear of the vehicle body toward the front of the vehicle body, a pressure maintaining valve accommodating hole 20 f is formed in parallel (refer to FIGS. 4 and 5 ) to the plunger accommodating hole 20 a and positioned obliquely rightwardly downwards with respect to the plunger accommodating hole 20 a . The pressure maintaining valve accommodating hole 20 f is open at a rear end thereof to the oil reserving chamber 28 surrounded by the annular packing 20 e.
[0084] Further, before the cap 21 is mounted on the tensioner body 20 , a spring receiver 29 a , a closing coil spring 29 b and a valve body 29 c of the pressure maintaining valve 29 are successively fitted through an opening of the pressure maintaining valve accommodating hole 20 f of the tensioner body 20 . A rear cylindrical circumferential face 29 d of the valve body 29 c is formed with a reduced diameter. The valve body 29 c is biased rearwardly as shown in FIG. 4 by spring restoring force of the closing coil spring 29 b so that a rear end face 29 e of the rear cylindrical circumferential face 29 d of the valve body 29 c is abutted by the front end face 21 b of the cap 21 to close up a communication port 20 g of the tensioner body 20 which is in communication with a relief valve port 22 e of the valve holder 22 .
[0085] It is to be noted that the relief valve port 22 e formed in the valve holder 22 is configured from a circumferential groove 22 f formed on an outer circumferential face of the base end portion 22 a , and a plurality of communication holes 22 g formed on the bottom of the circumferential groove toward the center of the valve accommodating hole 22 c in a spaced relationship from each other by an equal distance in the circumferential direction. If oil is relieved from the relief valve 26 , then the oil flows from a relief path formed from the relief valve port 22 e and the communication port 20 g to a returning path formed from the outer circumferential face of the pressure maintaining valve 29 and the pressure maintaining valve accommodating hole 20 f into the oil reserving chamber 28 .
[0086] A purge valve 30 will now be described.
[0087] As shown in FIG. 3 in which the tensioner body 20 is viewed from the rear of the vehicle body toward the front, a purge valve accommodating hole 20 h having a circular transverse section is formed in parallel to the plunger accommodating hole 20 a at a position obliquely leftwardly upwards with respect to the plunger accommodating hole 20 a . The purge valve accommodating hole 20 h is in communication at a rear portion thereof with the high pressure oil chamber 31 through a purge path 30 a as shown in FIGS. 4 and 5 .
[0088] Further, as shown in FIG. 8 , a valve body 30 b , a coil spring 30 e and a spring receiving tubular body 30 f are fitted successively in the purge valve accommodating hole 20 h from a front open end of the purge valve accommodating hole 20 h . The spring receiving tubular body 30 f is screwed integrally in the purge valve accommodating hole 20 h.
[0089] Further, an annular groove 30 c of a substantially rectangular (or square) cross section is formed on a circumferential face of the valve body 30 b , and an annular valve body 30 d having a substantially rectangular (or square) cross section is fitted in the annular groove 30 c . If a pressure variation in the high pressure oil chamber 31 is transmitted to the valve body 30 b through the purge path 30 a , then the valve body 30 b is moved back and forth in the forward and backward directions by the elastic restoring force of the coil spring 30 e . Thereupon, air contained in the oil is separated from the oil and discharged into the atmospheric air.
[0090] Finally, an oil supplying system will be described.
[0091] As shown in FIG. 6 , the oil reserving chamber 28 configured from the rear end face 20 c of the tensioner body 20 , concave face 21 c of the cap 21 and rear end face 20 c of the tensioner body 20 is connected at a lower portion thereof to a cylinder head oil path 33 formed in the lifter attaching portion 6 a of the cylinder head 6 through a tensioner oil path 32 extending in a downwardly inclined relationship from a rear portion to a front portion through the tensioner body 20 as shown in FIGS. 3 and 6 . As shown in FIG. 1 , the cylinder head oil path 33 is connected to an oil filter 35 through an oil path 34 of the crankcase 4 through an oil path not shown in the cylinder block 5 . The oil filter 35 is connected to a discharge port of an oil pump 37 through an oil path 36 , and oil reserved on the bottom of the crankcase 4 is sucked into the oil pump 37 through a strainer 38 by the oil pump 37 which is placed into an operative state in an interlocking relationship with operation of the internal combustion engine 3 . Oil discharged from the oil pump 37 is supplied to the oil reserving chamber 28 through the oil path 36 , oil filter 35 , oil path 34 , cylinder head oil path 33 and tensioner oil path 32 .
[0092] In the present embodiment, an oil supply path 40 signifies a path up to a valve hole 26 e configured from the tensioner oil path 32 , the oil reserving chamber 28 and the valve chamber 26 b of the relief valve 26 .
[0093] In the embodiment shown in FIGS. 1 to 8 , if the internal combustion engine 3 starts its operation, then the oil pump 37 is placed into an operative state, and oil is fed from the discharge port of the oil pump 37 to the cylinder head oil path 33 of the lifter attaching portion 6 a of the cylinder head 6 as described hereinabove. Then, the oil is fed into the oil reserving chamber 28 through the tensioner oil path 32 of the tensioner body 20 as shown in FIG. 6 and flows into the valve chamber 26 b of the relief valve 26 from the opening 27 a of the relief valve seat 27 .
[0094] If the pressure in the oil reserving chamber 28 rises and exceeds a cracking pressure, then the check valve 25 is opened and the oil flows into the high pressure oil chamber 31 through the valve hole 26 e of the relief valve 26 , whereupon the plunger 23 is projected forwardly until the abutting portion 23 c of the plunger 23 is abutted with the tensioner slipper 15 . Then, the plunger 23 forwardly pushes the tensioner slipper 15 strongly with the oil pressure in the high pressure oil chamber 31 to place the endless timing chain 13 on the relax side into a tensioned state thereby to suppress flapping of the endless timing chain 13 .
[0095] On the other hand, in a state in which the internal combustion engine 3 stops and the oil pressure in the oil reserving chamber 28 is low, the pressure maintaining valve 29 is closed by the spring restoring force of the closing coil spring 29 b of the pressure maintaining valve 29 as shown in FIG. 4 . However, if the oil pressure in the oil reserving chamber 28 rises in an interlocking relationship with starting of the internal combustion engine 3 , then it overcomes the spring restoring force of the closing coil spring 29 b thereby to push the valve body 29 c of the pressure maintaining valve 29 forwardly so that the rear cylindrical circumferential face 29 d of the reduced diameter of the pressure maintaining valve 29 approaches the communication port 20 g of the tensioner body 20 . Then, when the communication port 20 g is opened as shown in FIG. 5 , the oil flows into the relief valve port 22 e of the valve holder 22 .
[0096] If, in such a state as just described, the tensioner slipper 15 is tilted rearwardly and the plunger 23 is pushed back strongly by variations of the rotating torque of the driving sprocket wheel 10 by an intermittent pressure rise of the pressure in the fuel chambers in the internal combustion engine 3 or the like, then the oil pressure in the high pressure oil chamber 31 rises, whereupon the valve body 26 a of the relief valve 26 moves rearwardly. Consequently, an abutting face 26 f of the relief valve 26 is spaced away from a valve seat 25 d of the check valve 25 , whereupon the oil in a valve chamber 25 e of the check valve 25 flows from between the valve seat 25 d and the abutting face 26 f of the tip portion 26 c of the relief valve 26 back into the oil reserving chamber 28 through the relief valve port 22 e of the valve holder 22 and the communication port 20 g and the pressure maintaining valve accommodating hole 20 f of the tensioner body 20 . Consequently, an extraordinary increase in tension of the endless timing chain 13 is inhibited and flapping of the tensioner slipper 15 is suppressed.
[0097] Further, in the hydraulic tensioner disclosed in Japanese Patent Laid-Open No. 2009-180359 described hereinabove, since the pressure maintaining valve and the check valve are connected in series, oil fed from the discharge port of the oil pump cannot flow into the high pressure oil chamber if it does not pass through the check valve after it passes through the pressure maintaining valve. However, in the present embodiment, since the pressure maintaining valve 29 and the check valve 25 are connected in parallel to each other, even in a state in which the pressure maintaining valve 29 is closed, if the check valve 25 is opened, then the oil can flow into the high pressure oil chamber 31 . Therefore, in immediate response to starting of the internal combustion engine 3 , the oil is supplied into the high pressure oil chamber 31 . Consequently, the starting responsibility of the hydraulic tensioner 0 is improved, and the internal combustion engine 3 can start its operation smoothly.
[0098] Further, in the hydraulic tensioner disclosed in Japanese Patent Laid-Open No. 2009-180359 1 described hereinabove, the check valve is not opened until after oil pressure from the oil pump has been fed by a volume equal to the product of the area of the transverse section of the valve hole of the pressure maintaining valve and the stroke necessary for opening of the pressure maintaining valve. Therefore, the hydraulic tensioner cannot exhibit its function. However, in the present embodiment, if the check valve 25 is opened, then the hydraulic tensioner 0 can immediate exhibit its function independently of the opening of the pressure maintaining valve 29 . Therefore, the hydraulic tensioner of the present embodiment can exhibit its superior function sufficiently particularly in a hybrid vehicle wherein operation of the internal combustion engine 3 stops when the vehicle stops.
[0099] Furthermore, in the hydraulic tensioner disclosed in Japanese Patent Laid-Open No. 2009-180359 described hereinabove, the pressure maintaining valve is disposed on the oil pump side with respect to the check valve and the relief valve, and the pressure in the high pressure oil chamber acts upon the pressure maintaining valve. Therefore, the pressure maintaining valve requires a sealing property equivalent to that of the check valve, and consequently, there is the possibility that the cost may increase. However, in the present embodiment, since the pressure maintaining valve 29 is disposed in parallel to the check valve 25 and the relief valve 26 , it does not require a high sealing property and is advantageous in terms of the cost.
[0100] A second embodiment of the present invention shown in FIGS. 9 and 10 will be described.
[0101] A pressure maintaining valve 39 is used in place of the pressure maintaining valve 29 shown in FIGS. 1 to 8 . In this pressure maintaining valve 39 , a pressure maintaining valve port 39 f is formed on an outer circumferential portion 39 e of a valve head portion 39 d of a valve body 39 c , and a communication hole 39 g is formed in a spring receiver 39 a . This communication hole 39 g is in communication with an oil draining path 6 b of the cylinder head 6 through a drain oil path 20 i of the rear end face 20 c , and the spring receiver 39 a , a closing coil spring 39 b and the valve body 39 c are successively fitted through an opening of the pressure maintaining valve accommodating hole 20 f . Where the oil pressure in the oil reserving chamber 28 is lower than a predetermined pressure, the valve head portion 39 d is abutted with the front end face 21 b of the cap 21 under the spring restoring force of the closing coil spring 39 b of the pressure maintaining valve 39 as shown in FIG. 9 . Consequently, the communication between the pressure maintaining valve port 39 f provided in the valve head portion 39 d and the communication port 20 g of the valve holder 22 is blocked.
[0102] However, if the rotational frequency of the oil pump 37 increases until the check valve 25 is opened by the increasing oil pressure in the oil reserving chamber 28 , then the oil is supplied into the high pressure oil chamber 31 and the plunger 23 is projected to push the tensioner slipper 15 sufficiently so that suitable tension can be applied to the endless timing chain 13 . In this state, the increasing oil pressure in the oil reserving chamber 28 is transmitted to the pressure maintaining valve accommodating hole 20 f , and by the oil pressure, the pressure maintaining valve port 39 f of the pressure maintaining valve 39 is in communication with the communication port 20 g and the relief valve port 22 e . Therefore, when the oil pressure in the high pressure oil chamber 31 exceeds the relief pressure of the relief valve 26 , the relief valve 26 is opened, and the oil in the high pressure oil chamber 31 is fed to the oil draining path 6 b through the drain oil path 20 i passing the relief path configured from the relief valve port 22 e , communication port 20 g , pressure maintaining valve port 39 f and communication hole 39 g from the relief valve 26 . Meanwhile, the oil in the high pressure oil chamber 31 whose pressure exceeds the relief pressure of the relief valve 26 is discharged into the space in the internal combustion engine from the oil draining path 6 b irrespective of the oil in the oil reserving chamber 28 . As a result, extraordinary tension to the endless timing chain 13 can be prevented.
[0103] Also in the present embodiment, similarly as in the embodiment of FIGS. 1 to 8 , the circuit which establishes communication from the oil reserving chamber 28 to the pressure maintaining valve accommodating hole 20 f of the pressure maintaining valve 39 is connected in parallel to the circuit which establishes communication from the oil reserving chamber 28 to the high pressure oil chamber 31 through the valve chamber 26 b of the relief valve 26 , valve chamber 25 e of the check valve 25 and relief valve port 22 e . Therefore, this point provides effects similar to those in the first embodiment.
[0104] In the first and second embodiments described above, in the state in which the oil pump 37 stops, oil released from the high pressure oil chamber 31 by the relief valve 26 is filled only between the downstream of the check valve 25 and the relief valve port 22 e and communication port 20 g which form the relief path communicating with the pressure maintaining valve 29 and the pressure maintaining valve 39 , and the pressure is maintained. Consequently, the oil pressure in the relief valve 26 is equal to the oil pressure in the oil supply path 40 . Therefore, oil of a high pressure is not filled, and consequently, the relief valve 26 does not require a high sealing property. This makes it possible to achieve reduction of the cost.
[0105] Further, in the state in which the pressure maintaining valves 29 and 39 are acted upon by oil pressure from the oil reserving chamber 28 , the relief valve port 22 e and the communicating port 20 g which form the relief path and the oil supply path 40 are in communication with each other and oil is circulated. Consequently, insufficient supply of oil to the hydraulic tensioner 0 is suppressed.
[0106] Furthermore, only by partly modifying the shape of the valve bodies 29 c and 39 c of the pressure maintaining valves 29 and 39 , the returning path can be configured in a simplified structure.
[0107] Furthermore, since oil is not returned to the oil reserving chamber 28 side, an increase of the oil pressure in the oil supply path 40 is suppressed, and the necessity to raise the sealing property of the check valve 25 , relief valve 26 and pressure maintaining valves 29 and 39 is eliminated and reduction of the cost of the hydraulic tensioner 0 can be anticipated.
[0108] Besides, since the valve bodies 29 c and 39 c of the pressure maintaining valves 29 and 39 have a simple cylindrical shape, also the pressure maintaining valve accommodating hole 20 f between the relief valve port 22 e and communication port 20 g and the drain oil path 20 i of the tensioner body 20 may be formed in a simple shape. Besides, since the pressure maintaining valve 39 is structured such that high pressure relief oil is discharged into the drain oil path 20 i through the inside of the valve body 39 c of the pressure maintaining valve 39 , the drain oil path 20 i is simplified and reduction of the cost can be anticipated.
[0109] Further, since the oil supply path 40 can be configured utilizing the valve holder 22 , the oil supply path 40 is simplified and reduction of the cost can be anticipated.
[0110] Furthermore, supply oil can be supplied smoothly into the hydraulic tensioner 0 through an opening 7 a formed in the relief valve seat 27 serving as a holding plate.
[0111] Furthermore, in the relief valve port 22 e formed in the valve holder 22 , a converging discharge path is configured from a plurality of communicating holes directed in radial directions from the valve accommodating hole 22 c and a circumferential groove formed on an outer circumferential face of the base end portion 22 a in a communicating relationship with the communicating holes. Therefore, a simple oil path can be configured from the single pressure maintaining valve 29 or 39 by disposing the pressure maintaining valve 29 or 39 such that it is connected to the converging discharge path.
[0112] FIG. 11 is a right side elevational view of essential part illustrating a state in which an internal combustion engine 3 which includes a hydraulic tensioner 0 is attached to a vehicle body frame 1 of a motorcycle. In FIG. 11 , the rightward direction is the forward direction of the vehicle. Referring to FIG. 11 , the four-stroke cycle DOHC internal combustion engine 3 which includes the hydraulic tensioner 0 is incorporated in the motorcycle. The internal combustion engine 3 is attached to a hanger 2 provided at a front portion of the vehicle body frame 1 of the motorcycle and a rear portion of the vehicle body frame 1 through two bosses 8 projecting from the internal combustion engine 3 .
[0113] In the internal combustion engine 3 , a cylinder block 5 , a cylinder head 6 and a head cover 7 are successively placed in order in the upward direction on a crankcase 4 and are coupled integrally by a coupling device such as bolts. A crankshaft 9 is supported for rotation at a position sandwiched between the crankcase 4 and the cylinder block 5 of the internal combustion engine 3 . A pair of camshafts 11 is supported for rotation on the cylinder head 6 in the cylinder head 6 and the head cover 7 . An endless timing chain 13 extends between and around a driving sprocket wheel 10 , which is integrated with the crankshaft 9 , and a driven sprocket wheel 12 , which is integrated with the paired camshafts 11 . The crankshaft 9 is driven to rotate by upward and downward movement of pistons fitted for sliding movement in cylinder bores of the cylinder block 5 , and rotating torque of the crankshaft 9 is transmitted to the paired camshafts 11 through the driving sprocket wheel 10 , endless timing chain 13 and driven sprocket wheel 12 so that intake and exhaust valves are driven for opening and closing movement.
[0114] In the four-stroke cycle internal combustion engine 3 , fuel in a combustion chamber burns every time the crankshaft 9 rotates twice, and the pistons are intermittently pushed toward the crankshaft 9 by pressure of the combustion gas. Further, since the traveling resistance varies in response to concaves and convexes of the road surface on which the motorcycle travels, the tension state of the endless timing chain 13 varies and the endless timing chain 13 is liable to flap in the forward and backward directions. In order to prevent this, a chain guide 14 is disposed in contact with the endless timing chain 13 on the tension side positioned rightwardly (forwardly of the vehicle) in FIG. 11 while a tensioner slipper 15 is disposed in contact with the endless timing chain 13 on the relax side positioned leftwardly (rearwardly of the vehicle) in FIG. 11 . Further, the hydraulic tensioner 0 is assembled to the cylinder head 6 rearwardly of and adjacent to the tensioner slipper 15 . By a characteristic of the hydraulic tensioner 0 , flapping of the endless timing chain 13 on the relax side can be suppressed effectively.
[0115] FIG. 12 is a rear elevational view of the tensioner 0 , that is, a view as viewed in the direction indicated by an arrow mark II of FIG. 11 . The shell of the hydraulic tensioner 0 is configured from a tensioner body 20 and a cap 21 ( FIGS. 12 and 14 ). The cap 21 has a pair of left and right bolt fitting holes 21 a provided therein.
[0116] FIG. 13 is a view of the tensioner body 20 as viewed from the rear with the cap 21 removed. Bolts not shown which are fitted in the paired left and right bolt fitting holes 21 a ( FIG. 12 ) provided in the cap 21 shown extend through bolt fitting holes 20 b ( FIG. 13 ) of the tensioner body 20 and are screwed in a tensioner attaching portion 6 a ( FIG. 11 ) of a rear portion of the cylinder head 6 to mount the hydraulic tensioner 0 integrally on the cylinder head 6 . In FIG. 13 , a plunger accommodating hole 20 a ( FIG. 13 ) in which a plunger 23 and a valve holder 22 ( FIG. 14 ) are fitted extends through the center of the tensioner body 20 .
[0117] FIG. 14 is a sectional view taken along line Iv-Iv of FIG. 12 and is a longitudinal sectional view of the tensioner 0 . Arrow marks Fr and Re indicate directions as forward and backward directions of the tensioner itself in order to indicate the positions of the member of the tensioner 0 , and Fr indicates the forward direction and Re indicates the rearward direction. The shell of the tensioner 0 is configured from the tensioner body 20 and the cap 21 . In a state in which the cap is removed, a plunger 23 , a coil spring 24 and a valve holder 22 are successively mounted from the rear end side of the tensioner body 20 in the plunger accommodating hole 20 a provided at a central portion of the tensioner body 20 . The plunger 23 is slidable forwardly and backwardly in the plunger accommodating hole 20 a . The plunger 23 is biased so as to project forwardly by spring restoring force of the coil spring 24 . It is to be noted that an abutting portion 23 c is integrally mounted at a tip portion 23 a of the plunger 23 .
[0118] A check valve 25 , a relief valve 26 and a relief valve seat 27 are successively mounted in a valve accommodating hole 22 c ( FIG. 15 ) formed at a base end portion 22 a ( FIG. 15 ) of the valve holder 22 . A pressure maintaining valve 29 is mounted from a rear end of the tensioner body 20 in a pressure maintaining valve accommodating hole 20 f provided at a lower portion of the tensioner body 20 . A purge valve 30 is mounted from a front portion of a purge valve accommodating hole 20 h ( FIG. 13 ) provided at an upper portion of the tensioner body 20 . An oil reserving chamber 28 is defined by and between an inner face of the cap 21 and a rear end of the valve holder 22 . The circumference of the oil reserving chamber 28 is surrounded by an annular packing 20 e ( FIG. 13 ) fitted in a packing fitting groove 20 d ( FIG. 13 ). A high pressure oil chamber 31 is defined by and between an inner face of the plunger 23 and an outer face of a coil spring holding body 22 d of the valve holder 22 .
[0119] FIG. 15 is a fragmentary perspective view of the plunger 23 , coil spring 24 , valve holder 22 , check valve 25 , relief valve 26 , relief valve seat 27 and cap 21 inserted in the plunger accommodating hole 20 a . The coil spring 24 is interposed between an inner face 23 b of the tip portion 23 a of the plunger 23 and a stepped portion front end face 22 b of the valve holder 22 . A valve guide 25 a of the check valve 25 is fitted at a front portion of the valve accommodating hole 22 c formed in the base end portion 22 a of the valve holder 22 . A check valve coil spring 25 b and a spherical valve body 25 c are successively fitted in the forward direction from a rear portion with the valve guide 25 a.
[0120] A valve body 26 a of the relief valve 26 is fitted for sliding movement in a rear portion of the valve accommodating hole 22 c , and a relief valve coil spring 26 d is interposed between the relief valve seat 27 disposed in the oil reserving chamber 28 and a tip portion 26 c of the valve body 26 a of the relief valve 26 in a valve chamber 26 b of the valve body 26 a of the relief valve 26 . The oil reserving chamber 28 is connected to the high pressure oil chamber 31 through an opening 27 a of the relief valve seat 27 , the relief valve 26 , the check valve 25 and a through-hole 22 f of the coil spring holding body 22 d of the valve holder 22 .
[0121] Referring to FIG. 13 , the pressure maintaining valve accommodating hole 20 f is formed in parallel to the plunger accommodating hole 20 a and positioned obliquely rightwardly downwards with respect to the plunger accommodating hole 20 a , and the pressure maintaining valve 29 is accommodated in the pressure maintaining valve accommodating hole 20 f . The pressure maintaining valve accommodating hole 20 f is open at a rear end thereof to the oil reserving chamber 28 ( FIG. 14 ) surrounded by the annular packing 20 e.
[0122] FIG. 16 illustrates a disassembled state of the pressure maintaining valve 29 . In a state in which the cap is removed, a spring receiver 29 a , a closing coil spring 29 b and a valve body 29 c of the pressure maintaining valve 29 are successively fitted from the opening of the pressure maintaining valve accommodating hole 20 f of the tensioner body 20 . A rear cylindrical circumferential face 29 d of the valve body 29 c is formed with a reduced diameter. The valve body 29 c is biased rearwardly as illustrated in FIG. 14 by spring restoring force of the closing coil spring 29 b until a rear end face 29 e of the rear cylindrical circumferential face 29 d of the valve body 29 c is abutted with a front end face 21 b ( FIG. 14 ) of the cap 21 . Consequently, a communication port 20 g ( FIGS. 4 and 6 ) of the tensioner body 20 which is in communication with the relief valve port 22 e ( FIGS. 4 and 5 ) of the valve holder 22 is closed up. It is to be noted that the relief valve port 22 e formed in the valve holder 22 is configured from a circumferential groove formed on an outer circumferential face of the base end portion 22 a and a plurality of communicating holes formed toward the center of the valve accommodating hole 22 c in an equally spaced relationship from each other in the circumferential direction on the bottom of the circumferential groove.
[0123] Referring to FIG. 13 , the purge valve accommodating hole 20 h having a circular transverse section is formed in parallel to the plunger accommodating hole 20 a obliquely leftwardly upwards with respect to the plunger accommodating hole 20 a , and the purge valve 30 is accommodated in the purge valve accommodating hole 20 h . The purge valve accommodating hole 20 h is communicated at a rear portion thereof with the high pressure oil chamber 31 through a purge path 30 a as shown in FIG. 14 .
[0124] FIG. 16 illustrates a disassembled state of the purge valve 30 . A valve body 30 b , a coil spring 30 e and a spring receiving tubular body 30 f are fitted successively in the purge valve accommodating hole 20 h from a front open end of the purge valve accommodating hole 20 h . The spring receiving tubular body 30 f is screwed integrally in the purge valve accommodating hole 20 h . An annular groove 30 c of a substantially rectangular cross section is formed on a circumferential face of the valve body 30 b , and an annular valve body 30 d having a substantially rectangular cross section is fitted in the annular groove 30 c . If a pressure variation in the high pressure oil chamber 31 is transmitted to the valve body 30 b through the purge path 30 a , then the valve body 30 b is moved back and forth in the forward and backward directions by the elastic restoring force of the coil spring 30 e . Thereupon, air contained in the oil is separated from the oil and discharged to the outside from a front opening 30 g ( FIG. 14 ) of the purge valve 30 and an air emitting path 39 ( FIG. 14 ) of the tensioner attaching portion 6 a through a gap between the annular groove 30 c and the annular valve body 30 d.
[0125] FIG. 17 is a sectional view taken along line VII-VII of FIG. 12 . A tensioner oil path 32 (refer also to FIG. 13 ) is provided at a lower portion of the oil reserving chamber 28 configured from a rear end face 20 c of the tensioner body 20 and a concave face 21 c of the cap 21 and extends forwardly in a downwardly inclined relationship from the tensioner body 20 through the tensioner body 20 . This path 32 is connected to a cylinder head oil path 33 formed in the tensioner attaching portion 6 a of the cylinder head 6 . As shown in FIG. 11 , the cylinder head oil path 33 is connected to an oil filter 35 through an oil path not shown in the cylinder block 5 and through an oil path 34 of the crankcase 4 . The oil filter 35 is connected to a discharge port of an oil pump 37 through an oil path 36 , and oil reserved on the bottom portion of the crankcase 4 is sucked into the oil pump 37 through a strainer 38 by the oil pump 37 which is placed into an operative state in an interlocking relationship with operation of the internal combustion engine 3 . The oil discharged from the oil pump 37 is supplied into the oil reserving chamber 28 of the hydraulic tensioner 0 through the oil path 36 , the oil filter 35 , the oil path 34 , the cylinder head oil path 33 and the tensioner oil path 32 . Further, the oil is supplied from the oil reserving chamber 28 into the high pressure oil chamber 31 of the tensioner through the valve chamber 26 b and a valve hole 26 e of the relief valve 26 , a valve chamber 25 e and an opening 25 f of the check valve 25 and the through-hole 22 f of the valve holder 22 to drive the plunger 23 .
[0126] FIG. 18 illustrates a state in which the plunger 23 is projected forwardly when the pressure in the oil reserving chamber 28 rises and exceeds a cracking pressure to open the check valve 25 and the oil flows into the high pressure oil chamber 31 from the valve hole 26 e of the relief valve 26 through the valve chamber 25 e and opening 25 f of the check valve 25 and the through-hole 22 f of the valve holder 22 . Then, the abutting portion 23 c of the plunger 23 is abutted with the tensioner slipper 15 to push forwardly the tensioner slipper 15 ( FIG. 11 ) strongly with the oil pressure in the high pressure oil chamber 31 to place the endless timing chain 13 on the relax side into a tensioned state thereby to suppress flapping of the endless timing chain 13 .
[0127] In a state in which the internal combustion engine 3 stops and the oil pressure in the oil reserving chamber 28 is low, the pressure maintaining valve 29 is closed by the spring restoring force of the closing coil spring 29 b of the pressure maintaining valve 29 as shown in FIG. 14 . However, if the oil pressure in the oil reserving chamber 28 rises in an interlocking relationship with starting of the internal combustion engine 3 , then it overcomes the spring restoring force of the closing coil spring 29 b thereby to push the valve body 29 c of the pressure maintaining valve 29 forwardly so that the rear cylindrical circumferential face 29 d of the reduced diameter of the pressure maintaining valve 29 approaches the communication port 20 g of the tensioner body 20 . Consequently, since the communication port 20 g is opened as shown in FIG. 18 , the oil flows into the relief valve port 22 e of the valve holder 22 .
[0128] If, in such a state as just described, the tensioner slipper 15 is tilted rearwardly and the plunger 23 is pushed back strongly by variations of the rotating torque of the driving sprocket wheel 10 by an intermittent pressure rise of the pressure in a fuel chamber in the internal combustion engine 3 or the like, then the oil pressure in the high pressure oil chamber 31 rises, whereupon the valve body 26 a of the relief valve 26 moves rearwardly. Consequently, the abutting face 26 f ( FIG. 15 ) of the tip portion 26 c of the relief valve 26 is spaced away from the valve seat 25 d ( FIG. 15 ) of the check valve 25 , whereupon the oil in a valve chamber 25 e of the check valve 25 flows from between the valve seat 25 d and the abutting face 26 f of the tip portion 26 c of the relief valve 26 back into the oil reserving chamber 28 through the relief valve port 22 e of the valve holder 22 and the communication port 20 g and the pressure maintaining valve accommodating hole 20 f of the tensioner body 20 . Consequently, an extraordinary increase in tension of the endless timing chain 13 is inhibited and flapping of the tensioner slipper 15 is suppressed.
[0129] Referring to FIG. 16 , the plunger accommodating hole 20 a of the tensioner body 20 is configured from a large diameter portion 41 at a rear portion and a small diameter portion 42 at a front portion, and a stepped portion 43 is formed on the boundary between them. Referring to FIG. 15 , also the plunger 23 includes a large diameter portion 44 at a rear portion and a small diameter portion 45 at a front portion, and a stepped portion 46 is formed on the boundary between them. The plunger 23 is inserted into the tensioner body 20 from the rear. When the plunger is pushed by the pressure in the high pressure oil chamber 31 and projected forwardly until the stepped portion 46 of the plunger 23 is abutted with the stepped portion 43 of the plunger accommodating hole 20 a , then the plunger 23 stops its forward movement. In other words, both stepped portions act as stoppers for preventing coming off of the plunger.
First Leak Oil Emission Device:
[0130] FIG. 19 is a partial enlarged view of a gap portion 40 of FIG. 14 . Although the gap between the tensioner body 20 and the plunger 23 is a gap in which the plunger 23 can slidably move, it is small to such a degree that no play occurs. In response to sliding movement of the plunger 23 , oil in the high pressure oil chamber 31 enters the gap and enters a portion 49 of a large gap sandwiched between the stepped portions 43 and 46 . When the plunger 23 moves forwardly, the oil in the portion 49 of the large gap is compressed. If the leak amount from a small diameter portion gap 48 at the front portion is small, then the forward movement of the plunger 23 is blocked. Accordingly, the area of the small diameter portion gap 48 on the downstream side is made greater than the area of a large diameter portion gap 47 so that flowing out of the oil is not blocked. In the present embodiment, with regard to both of the plunger accommodating hole 20 a and the plunger 23 , the upstream side is formed as a large diameter portion and the downstream side is formed as a small diameter portion in the flow of the flowing out oil.
[0131] Since the gap is very small, upon working of the inner diameter of the plunger accommodating hole 20 a and the outer diameter of the plunger 23 , a method for determination of the dimension of the small diameter portion gap 48 is described below assuming that reference dimensions (inner diameters and outer diameters) and working tolerances are set appropriately so that the large diameter portion gap 47 may have a required dimension. In particular, the inner diameters and the outer diameters (reference dimensions) and the working tolerances of the required portions are set such that the gap dimension B when the dimension of the small diameter portion gap 48 is formed smallest may be greater than the gap dimension A when the dimension of the large diameter portion gap 47 is formed greatest. In particular, where A=“allowable maximum value of the inner diameter of the plunger accommodating hole large diameter portion 41 ”—“allowable minimum value of the outer diameter of the plunger accommodating hole large diameter portion 44 ” and B=“allowable minimum value of the inner diameter of the plunger accommodating hole small diameter portion 42 ”—“allowable maximum value of the outer diameter of the plunger accommodating hole small diameter portion 45 ,” the reference dimensions (inner diameters and outer diameters) and the working tolerances (allowable maximum values and allowable minimum values) with which the relationship of A<B may be satisfied are set.
[0132] While the leak oil emission device tries to manage the accuracy in area or dimension of the entire gap between the plunger accommodating hole 20 a and the plunger 23 , the following description is directed to leak oil emission device which forms an oil emitting groove 51 on a small diameter portion of the plunger accommodating hole 20 a.
Second Leak Oil Emission Device:
[0133] FIG. 20 is a front elevational view of the tensioner body 20 . FIG. 21 is a sectional view taken along line XI-XI of FIG. 20 . A working tool 50 is applied to the small diameter portion 42 of the plunger accommodating hole 20 a from the front face of the tensioner body 20 to form the oil emitting groove 51 , and the groove 51 is formed until the tip of the working tool 50 reaches the large diameter portion 41 of the plunger accommodating hole 20 a . This can enhance the emitting performance of oil.
[0134] The leak oil emission device described in detail above has the following characteristics and effects.
[0135] 1. Of the gaps between the plunger accommodating hole 20 a and the plunger 23 , the area of the small diameter portion gap 48 on the downstream side from which oils flows out is greater than the area of the large diameter portion gap 47 on the upstream side. By making the gap area on the upstream side set for oil pressure adjustment small and making the gap area on the downstream side greater than that on the downstream side, the oil emission performance on the downstream side which does not act for oil pressure adjustment is enhanced to reduce the sliding resistance of the plunger 23 by oil resistance. Consequently, the movement of the plunger 23 can be smoothened.
[0136] 2. The reference dimensions and the working tolerances of the plunger accommodating hole 20 a and the plunger 23 are set such that the gap dimension where the dimension of the small diameter portion gap 48 on the downstream side is formed smallest is greater than the gap dimension in the case where the dimension of the large diameter portion gap 47 on the upstream side is formed greatest to carry out working. Consequently, the dimension management of the gaps can be made sure and the oil emitting property of the downstream side can be enhanced.
[0137] 3. The oil emitting groove 51 is formed on the sliding face of the plunger accommodating hole small diameter portion 42 of the tensioner body 20 , and the upstream end thereof reaches the plunger accommodating hole large diameter portion 41 . Consequently, the emitting performance of oil on the downstream side can be improved.
[0138] 4. The plunger 23 has the stepped portion 46 formed from the plunger large diameter portion 44 on the upstream side and the plunger small diameter portion 45 on the downstream side, and the plunger accommodating hole 20 a of the tensioner body 20 has the plunger accommodating hole stepped portion 43 formed from the plunger accommodating hole large diameter portion 41 corresponding to the plunger large diameter portion 44 on the upstream side of the plunger 23 and the plunger accommodating hole small diameter portion 42 corresponding to the plunger small diameter portion 45 on the downstream side of the plunger. This plunger stepped portion 46 is engaged with the plunger accommodating hole stepped portion 43 to form a coming off preventing structure for the plunger 23 ( FIG. 19 ). The oil emitting groove 51 is formed on the plunger accommodating hole small diameter portion 42 such that the upstream end thereof extends to the plunger accommodating hole large diameter portion 41 . Accordingly, the oil emission property when the plunger 23 moves forwardly can be improved.
[0139] 5. The oil emitting groove 51 is formed by machining on the plunger accommodating hole small diameter portion 42 from the downstream end side and the working tool 50 is worked such that the tip thereof extends to the plunger accommodating hole large diameter portion 41 ( FIG. 21 ). Accordingly, the oil emitting groove 51 can be formed readily.
[0140] 6. The oil emitting groove 51 is disposed at a position clear of a plane (C-C plane of FIG. 20 ) including the direction of movement of the endless timing chain 13 and the axial line of the plunger 23 . This is because, since the plunger 23 vibrates in the direction of movement of the endless timing chain 13 , if the oil emitting groove 51 is provided in the plane including the direction of movement of the endless timing chain 13 and the plunger 23 , then there is the possibility that an edge of the oil emitting groove 51 may damage the plunger 23 , it is intended to avoid this.
[0141] 7. In a state in which the hydraulic tensioner 0 is attached to the vehicle, the hydraulic tensioner 0 is attached such that the oil emitting direction of the oil emitting groove 51 is directed downwardly from the horizontal direction ( FIG. 11 ). Consequently, since also emission by the self weight of oil becomes possible, the oil can be emitted well.
[0142] 8. The oil emitting groove 51 is provided in a pair at opposing positions with respect to the center line of the plunger accommodating hole 20 a of the tensioner body 20 ( FIG. 20 ). By disposing such oil emission grooves not at neighboring positions but in a spaced relationship in opposing disposition, oil can be emitted well while suppressing a drop in strength of the tensioner body 20 .
[0143] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A hydraulic tensioner applies appropriate tension to an endless power transmitting belt. The hydraulic tensioner includes a plunger body, an oil supply path, a check valve, a relief valve, a pressure maintaining valve interposed in a relief path and a pressure accommodating hole. The hydraulic tensioner is configured such that a path that is branched from the oil supply path for operating the pressure maintaining valve is formed independently of a supply path to the check valve. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a 35 U.S.C. 371 National Phase Entry Application from PCT/JP2006/313780, filed Jul. 11, 2006, which claims the benefit of Japanese Patent Application No. 2005-219136 filed on Jul. 28, 2005, the disclosure of which is incorporated herein in its entirety by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not Applicable
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an apparatus for performing a realistic loop simulation of a knitted fabric, a loop simulation method, and a loop simulation program.
The present applicant has proposed that a loop simulation be performed by determining the position of stitches using an empirical rule based on the type of stitch, connection relationships with adjacent stitches and so on (Japanese Unexamined Patent Application 2005-120501). However, this method is problematic in that:
the basis for the loop simulation is dependent on an empirical rule, and therefore ambiguous, and it is difficult to simulate a bulging knitted fabric such as a pin tuck pattern. Furthermore, it is difficult to simulate the curl at the ends of the knitted fabric.
The latter two problems can be expressed together as difficulty in simulating the three-dimensional structure of the knitted fabric.
BRIEF SUMMARY OF THE INVENTION
The basic objects of the present invention are to minimize the use of empirical rules during a loop simulation while keeping the calculation load within a feasible range, and to express three-dimensional bulges, curls and so on of a knitted fabric.
A loop simulation apparatus according to the present invention is an apparatus for creating a knitted fabric image corresponding to design data of a knitted fabric such that a loop of each individual stitch is represented, characterized by: means for determining a distance deviation between a distance from each individual stitch on the knitted fabric image to an adjacent stitch and a standard value thereof as a tension; means for determining a deviation between an intersection angle between a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a course direction and a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a wale direction and a standard value thereof as a distortion angle; means for determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the wale direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the course direction, and a standard value thereof as a bending angle about a course axis; means for determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the course direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the wale direction, and a standard value thereof as a bending angle about a wale axis; and shifting means for shifting a position of each individual stitch on the knitted fabric image to reduce the tension, the distortion angle, the bending angle about the course axis, and the bending angle about the wale axis.
A loop simulation method according to the present invention is a method for creating a knitted fabric image corresponding to design data of a knitted fabric such that a loop of each individual stitch is represented, characterized by the steps of: determining a distance deviation between a distance from each individual stitch on the knitted fabric image to an adjacent stitch and a standard value thereof as a tension; determining a deviation between an intersection angle between a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a course direction and a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a wale direction and a standard value thereof as a distortion angle; determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the wale direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the course direction, and a standard value thereof as a bending angle about a course axis; determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the course direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the wale direction, and a standard value thereof as a bending angle about a wale axis; and shifting a position of each individual stitch on the knitted fabric image to reduce the tension, the distortion angle, the bending angle about the course axis, and the bending angle about the wale axis.
A loop simulation program according to the present invention is a program that can be executed by a computer, for creating a knitted fabric image corresponding to design data of a knitted fabric such that a loop of each individual stitch is represented, characterized by: a command for determining a distance deviation between a distance from each individual stitch on the knitted fabric image to an adjacent stitch and a standard value thereof as a tension; a command for determining a deviation between an intersection angle between a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a course direction and a line linking each individual stitch on the knitted fabric image to an adjacent stitch in a wale direction and a standard value thereof as a distortion angle; a command for determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the wale direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the course direction, and a standard value thereof as a bending angle about a course axis; a command for determining a deviation between an angle between two stitches adjacent to each individual stitch on the knitted fabric image in the course direction, with respect to an axis expressing an orientation of each individual stitch on the knitted fabric image to an adjacent stitch in the wale direction, and a standard value thereof as a bending angle about a wale axis; and a command for shifting a position of each individual stitch on the knitted fabric image to reduce the tension, the distortion angle, the bending angle about the course axis, and the bending angle about the wale axis.
Preferably, when shifting the stitch positions, each stitch is shifted according to a total shift amount obtained by adding together shift amounts relating respectively to the tension, the distortion angle, the bending angle about the course axis and the bending angle about the wale axis, which have been determined with respect to each stitch of the knitted fabric image.
In the following specification, unless any indication is given to the contrary, description relating to the loop simulation apparatus applies as is to the loop simulation method and loop simulation program, and description relating to the loop simulation method and loop simulation program applies as is to the loop simulation apparatus. Further, the subject knitted fabric may be a flat knitted fabric or a circular knitted fabric, and may be a piece of knitted fabric or a garment.
In the present invention, four factors determine the positions of the stitches, namely the tension, the distortion angle, the bending angle about the course axis and the bending angle about the wale axis. Note that the deviation from the standard values thereof is set as a difference, for example, but may be a ratio or the like. The tension is based on the deviation between the interval to an adjacent stitch and a standard value, and reflects a quality whereby a spring assumed to connect the stitches to each other attempts to return to its natural length (the standard value) after expanding or contracting from its natural length. The distortion angle reflects a quality whereby a stability value is allocated to the angle of each apex of a square formed by four stitches, for example, which are close to each other in the course direction and wale direction, and when the angle deviates from the stability value, it attempts to return to its original angle.
The bending angle about the course axis and the bending angle about the wale axis correspond to a quality whereby each stitch is not flat, and the two ends of the stitch attempt to move to the front and back of the knitted fabric about the center of the stitch. When the standard value of the bending angle is set at 180 degrees, the stitches attempt to converge in plane, and when the standard value is shifted from 180 degrees, the knitted fabric attempts to curl. By employing the bending angle about the course axis and the bending angle about the wale axis, the manner in which the knitted fabric deviates from the plane and deforms three-dimensionally can be simulated.
The four factors described above are based on various forces acting on the stitches and the force exerted by the stitches themselves as they attempt to deform three-dimensionally, and are not simply modelizations of an empirical rule. Hence, a loop simulation based on a well-founded model can be performed. Furthermore, to perform a simulation using the model described above, it is only necessary to determine the tension, the distortion angle, and the bending angles bout the course axis and wale axis, and these factors are all amounts that can be calculated simply. Hence, the time required for the simulation can be held within a practical range. In the present invention, a virtual knitted fabric or garment obtained through a loop simulation of knitting data can be viewed as if placed on a flat surface, for example, and therefore the knitted fabric or garment can be evaluated without test knitting.
The stitches may be shifted every time the tension, distortion angle, and bending angles about the course axis and wale axis are determined, but in so doing, the positional relationships between the stitches vary while the deviations are determined. Therefore, it is easier to determine the tension, distortion angle, and bending angles about the course axis and wale axis for all of the stitches, for example, and then perform processing to shift each stitch in accordance with a total shift amount obtained by adding together the respective shift amounts of the tension, distortion angle, and bending angles about the course axis and wale axis.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a block diagram of a loop simulation apparatus according to an embodiment;
FIG. 2 is a block diagram of a loop simulation program according to this embodiment;
FIG. 3 is a flowchart showing a loop simulation algorithm according to this embodiment;
FIG. 4 is a view showing examples of parameter lists according to this embodiment;
FIG. 5 is a view showing tension processing according to this embodiment;
FIG. 6 is a view showing distortion processing of a right side stitch according to this embodiment;
FIG. 7 is a view showing distortion processing of a left side stitch according to this embodiment;
FIG. 8 is a view showing a model of a curl at the end of a knitted fabric;
FIG. 9 is a view showing wale direction bending processing performed on a left side stitch according to this embodiment;
FIG. 10 is a view showing wale direction bending processing performed on a right side stitch according to this embodiment;
FIG. 11 is a view showing course direction bending processing performed on an upper side stitch according to this embodiment;
FIG. 12 is a view showing course direction bending processing performed on a lower side stitch according to this embodiment; and
FIG. 13 is a view showing a pin tuck knitting procedure.
The reference symbols in the drawings are described as follows:
2 loop simulation apparatus 4 bus 6 user interface 7 manual input 8 monitor 10 printer 12 loop simulation program storage unit 14 LAN interface 16 disk drive 18 image memory 20 knitting data converter 22 loop length processor 24 tension processor 26 distortion processor 28 course direction bending processor 30 wale direction bending processor 32 synthesizer 34 collision determination unit 36 convergence determination unit 38 thread stripe information creation unit 40 rendering unit 52 loop simulation program 54 tension processing command 56 distortion processing command 58 course direction bending processing command 60 wale direction bending processing command 62 synthesis command 64 collision determination command 66 convergence determination command 68 thread stripe information creation command 70 rendering command 80 - 83 parameter lists 90 stitch model 91 stitch position 92 - 95 knitted fabric models P 0 stitch position P 1 -P 4 peripheral stitch positions Axis axis θ, φ default values of bending angles
DETAILED DESCRIPTION OF THE INVENTION
A best mode for carrying out the present invention will be described below.
FIGS. 1 to 13 show an embodiment. In the drawings, 2 denotes a loop simulation apparatus, 4 denotes a bus for data, commands and so on, 6 denotes a user interface for inputting a knitted fabric design through manual input 7 using a stylus, a mouse, a track ball, a keyboard or similar. Further, the loop length of a stitch, the material of the thread, the shrinkage factor during finishing and so on are input into the user interface 6 from the manual input 7 , as well as a standard value of the intersection angle between the course direction and the wale direction, or more precisely a standard value of an intersection angle between a line linking a subject stitch and an adjacent stitch in the course direction and a line linking the subject stitch and an adjacent stitch in the wale direction. Further, a standard value of an angle between two stitches on either side of an axis relating to a course direction axis, a standard value of an angle between two stitches on either side of an axis relating to a wale direction axis and so on are also input. The loop length, the thread material, the shrinkage factor during finishing, the standard value of the intersection angle, the standard values of the angles between stitches on either side of the axes and so on serve as simulation parameters.
8 denotes a display on which design data, loop simulation images of a knitted fabric and so on are displayed, while a printer 10 also outputs the knitted fabric design data, loop simulation images and so on. Note that a loop simulation image is an image simulating a virtual knitted fabric based on the design data of a knitted fabric such that individual loops (stitches) are represented realistically. The individual stitches have in-plane coordinates (x, y) and a coordinate (z coordinate) in an orthogonal direction to the in-plane coordinates, and the position of the stitch is represented by the base position of the stitch.
12 denotes a loop simulation program storage unit storing a program required to perform a loop simulation. FIG. 2 shows the program in detail. 14 is a LAN interface for inputting and outputting the knitted fabric loop simulation program, design data, knitting data based on the design data of the knitted fabric, loop simulation images and so on to and from a LAN. A disk drive 16 inputs and outputs data to and from a disk in a similar fashion to the LAN interface 14 . 18 denotes image memory storing images such as loop simulation images in a raster format, for example. 20 is a knitting data converter for converting knitted fabric data designed on the user interface 6 or the like into knitting data that can be knitted on a flatbed knitting machine. 22 is a loop length processor for outputting the loop length of individual stitches in accordance with the knitting data.
24 is a tension processor for outputting a difference between a distance from each individual stitch to four adjacent stitches in the wale direction and course direction, for example, and a default value, or in other words a standard value, as the tension. This tension value expresses tension generated when the distance between stitches deviates from the standard value. Note that in the following description, the term “adjacent stitches” signifies adjacent stitches in the wale direction and course direction, and when a right side stitch in the course direction or the like is being referred to, the terms “the adjacent right side stitch in the course direction” and so on will be used. In this embodiment, only the relationships between adjacent stitches are dealt with.
Further, the default value is determined here according to the loop length, and may signify the length of the thread per loop prior to stretching at the tension generated during knitting on a knitting machine, the length of the thread per loop during stretching at the tension of the knitting machine, or the length of the thread per loop following shrinkage when finishing is performed after the knitting is complete. The loop length may be assumed to vary in predetermined sections or in each individual stitch. The expansion and contraction of the thread at the tension of the knitting machine and during finishing depends on the material of the thread, and therefore the type of thread is also input into the user interface 6 .
A distortion processor 26 determines the angle of a triangle constituted by a single stitch adjacent to each individual stitch in the wale direction, a single stitch adjacent to each individual stitch in the course direction, and the subject stitch, or in other words an intersection angle. When the course direction and wale direction form a right angle, this angle, i.e. the intersection angle, should be 90 degrees. A standard value (default value) of the intersection angle is set at 90 degrees unless input indicating otherwise is received through the user interface 6 . The difference between the intersection angle and the standard value is the distortion angle, and each individual stitch has four intersection angles. Here, however, the intersection angle between the left side adjacent stitch in the course direction and one of the upper and lower stitches in the wale direction and the intersection angle between the right side stitch in the course direction and the aforementioned stitch in the wale direction are used, and therefore two intersection angles are determined for each individual stitch. A force for aligning the intersection angle with the default value acts on the adjacent stitch in accordance with the difference between the intersection angle and the default value, or in other words the distortion angle. The distortion angle expresses this force.
A course direction bending processor 28 is based on the fact that, with respect to the axis of the course direction, the two adjacent stitches in the wale direction become stable at a predetermined angle. Further, a wale direction bending processor 30 is based on the fact that, with respect to the axis of the wale direction, the two adjacent stitches in the course direction become stable at a predetermined angle. These processors 28 , 30 will be described in detail below with reference to FIG. 8 .
A synthesizer 32 shifts the individual stitches over the knitted fabric data. The positions of the stitches may be moved every time the tension, the distortion angle, and the bending angles about the course axis and wale axis are determined, but in this embodiment, the tension, the distortion angle and the bending angles about the course axis and wale axis are calculated in relation to all of the stitches. A weighting is then applied to these elements such that when the weighting of the tension is 1, for example, the other weightings are between approximately 1 and 0.1. The weighting is multiplied by each element, such as the tension, and the result is set as an individual shift amount. In the case of the tension, for example, four adjacent stitches exist as standard in the course direction and wale direction, and therefore four tension values are obtained. Hence, by multiplying a weighting by these values and then adding the results together, a total shift amount is generated in relation to the tension. In this manner, a total shift amount relating to the four factors described above is determined. The other shift amounts, such as the distortion angle, likewise include a plurality of elements per shift amount.
The total shift amount is determined for each individual stitch, whereupon the stitches are shifted. The shift amount includes the amount by which the subject stitch is moved and the amount by which adjacent stitches are moved. Note that if an attempt is made to shift a single stitch and its adjacent stitches every time the total shift amount relating to the stitch is determined and then determine the shift amount of the next stitch, calculation of the shift amount becomes unstable.
A collision determination unit 34 detects collisions between stitches such that when the positions of two stitches match in a horizontal plane, for example, and there is no difference in the diameter part of the thread on the z coordinate of the stitches, it is determined that a collision has occurred. When the collision determination unit 34 detects a collision, the shift amount is changed to a position at which the collision does not occur.
A convergence determination unit 36 determines whether or not the shift amount has converged to 0 or to a predetermined value or less when a process extending from calculation of the shift amount to correction of the shift amount through collision determination has been executed repeatedly. When the shift amount has converged or the number of processes has reached an upper limit, the convergence determination unit 36 terminates stitch position shifting, assuming that stable knitted fabric data have been obtained in relation to the four factors described above through simulation.
A thread stripe information creation unit 38 determines the thread stripe, i.e. the position of the thread or the flow of the thread, such that the determined stitch positions are connected. As a result, the thread position is determined. On the basis of this position, a rendering unit 40 implements rendering, and thus a loop simulation image is obtained.
FIG. 2 shows an outline of a loop simulation program 52 . This program is used to execute the loop simulation of this embodiment on a dedicated knit design apparatus, a personal computer, or similar. A tension processing command 54 is a command for mounting the tension processor 24 , and the content of the command is similar to the processing performed by the tension processor 24 . A distortion processing command 56 is a command for executing the processing of the distortion processor 26 . A course direction bending processing command 58 is a command for executing the processing of the course direction bending processor 28 . A wale direction bending processing command 60 is a command for executing the processing of the wale direction bending processor 30 .
A synthesis command 62 is a command for executing the processing of the synthesizer 32 . A collision determination command 64 is a command for executing the processing of the collision determination unit 34 . A convergence determination command 66 is a command for executing the processing of the convergence determination unit 36 . A thread stripe information creation command 68 is a command for executing the processing of the thread stripe information creation unit 38 . A rendering command 70 is a command for executing the processing of the rendering unit 40 .
FIG. 3 shows an algorithm of a loop simulation method according to this embodiment. The algorithm executes the operation of the apparatus 2 shown in FIG. 1 unless otherwise specified. Connection relationships (connection information) between each stitch and its adjacent stitches are determined from the knitting data, and the characteristics of the individual stitches, such as the stitch type (knit, tuck, miss), knit stitch, purl stitch, double stitch, racking amount and end stitch are determined from the connection information and registered as attributes. In addition, the loop length and so on are determined from the knitting data and added to the attributes. From the connection information and the attributes, the standard default values of the tension, distortion angle, course direction bending angle and wale direction bending angle are determined, and when specific input is provided in relation to these factors through the user interface 6 , the default values are set accordingly.
Respective shift amounts, i.e. shift vectors or correction vectors, are determined in relation to the tension, distortion angle and bending angles and gradually added to a shift vector array. This array is a data array, the individual elements of which are the respective shift amounts of the tension, distortion angle, wale direction bending angle and course direction bending angle of each stitch.
In parameter lists 80 to 83 shown in FIG. 4 , numerals such as 1, 2, 3 provided below the teen “connection” indicate stitch numbers. The angle unit is radians, in which the default values relating to the four elements are expressed. Here, the default value of the distortion, i.e. the distortion angle, is 90 degrees (1.57 rad), but may take a value other than 90 degrees. Further, when the default values of the wale direction bending angle and course direction bending angle deviate from 180 degrees (3.14 rad), the curl at the ends of the knitted fabric and the bulge of the knitted fabric can be expressed three-dimensionally. Note that similar lists are created in relation to the position of each stitch on the knitted fabric data, and the tension, distortion angle, course direction bending angle and wale direction bending angle are determined from the differences between the lists.
The shift amounts (shift vectors) of each of the tension, the distortion angle, the wale direction bending angle and the course direction bending angle are extracted from the array, multiplied by the weighting of each factor, and added together to produce a synthesized shift vector. Next, the presence of a collision between the subject stitch (each stitch) and the other stitches when each stitch is moved by the synthesized shift vector is determined, and when a collision occurs, the synthesized vector is corrected so as to avoid the collision.
The positions of all of the stitches, i.e. all of the stitches of the knitted fabric, are then shifted in accordance with the synthesized vector. When the stitch shift amount of a single process converges to substantially zero, thread stripe information is created using the position and attributes of the stitch and the position of adjacent stitches, whereupon rendering is performed to create a realistic loop simulation image.
FIG. 5 shows processing relating to the tension. Note that in the following description, P 0 denotes the subject stitch, and P 1 to P 4 denote adjacent stitches. The distance between P 0 and P 1 is determined and compared with the default value. The difference between the distance and the default value is then halved, and the result is set as the correction vector (tension) of the positions of the stitches P 0 , P 1 . Typically, the stitch P 0 has approximately four adjacent stitches, and therefore this processing is performed on each adjacent stitch. This is based on a model whereby each stitch is assumed to be connected by a spring and the natural length of the spring serves as the default value.
FIGS. 6 and 7 show processing relating to the distortion angle. Here, the default value of the intersection angle is indicated to be 90 degrees, and a perpendicular axis to a plane including the three points of the stitches P 0 , P 1 and P 2 is set as a rotary axis. This axis is not necessarily perpendicular to the plane of the entire knitted fabric. The difference between the angle P 1 -P 0 -P 2 and its default value is determined and set as the distortion angle, and the distortion angle is set as the correction vector relating to the stitches P 1 and P 2 . Although the correction vector appears to be too large, a weighting is multiplied by the correction vector when determining the synthesized shift vector, and therefore it does not matter here whether or not the correction vector is too large.
FIG. 8 shows a model of the curl of the knitted fabric. 90 denotes a stitch model, and 91 denotes a stitch position of the stitch. The drawing shows a plain face stitch, or knitted fabric models 92 to 95 constituted only by plain face stitches, from above. The lower side of the drawing corresponds to the front and the upper side corresponds to the back. In a plain face stitch, the center of the stitch tends to be pulled forward while the left and right ends tend to be pulled back. On a plain fabric formed by plain face stitch, the front-back pulling force is balanced in the center of the knitted fabric, or in other words during knitting, but since the knitted ends, i.e. the ends of the knitted fabric, are free, these knitted ends are pulled back. On an actual knitted fabric, the left and right ends of a plain fabric formed by plain face stitch curl backward due to this mechanism. Wale direction bending processing serves as processing corresponding to this phenomenon, and by repeating this processing, the left and right ends curl backward, as can be seen from the knitted fabric model 93 to the knitted fabric model 95 . Wale direction bending processing is processing for simulating bending in the knitted fabric about the wale direction, and the subject of the processing is not limited to the curl at either end of the knitted fabric.
A similar problem occurs as curling at the top and bottom of the knitted fabric, and when a plain face stitch is observed from the side, the two ends of the stitch are pulled forward and the center of the stitch is pulled backward. The upper end and lower end of the knitted fabric are free, and therefore forward direction curling occurs in these positions. This phenomenon is simulated by course direction bending processing, whereby bending displacement of the knitted fabric relating to the course direction axis is simulated.
FIG. 9 shows wale direction bending processing relating to the left side stitch P 1 . A rotary axis Axis is generated using the stitches P 2 , P 4 on the upper and lower sides of the subject stitch P 0 in the wale direction. More specifically, a symmetrical position P 4 ′ to the stitch P 0 is determined in relation to the lower side stitch P 4 , and the axis Axis is generated in an intermediate orientation between a vector POP 2 and a vector POP 4 ′. A position obtained by rotating the stitch P 3 about the axis Axis by an amount corresponding to a bending angle default value θ is set as P 3 ′. A position obtained by shifting the stitch P 1 to a position parallel to a vector approaching the position P 3 ′ from the axis Axis that passes through the stitch P 1 on a spherical surface having the foot of a perpendicular line to the axis as its center is set as P 1 ′. The vector from P 1 to P 1 ′ is set as the correction vector. The processing in FIG. 9 is processing for aligning the angle formed by the stitch P 1 and the stitch P 3 relative to the axis Axis with the bending angle default value θ. In consideration of the fact that the left and right sides of the stitch are pulled backward in the stitch model 90 shown in FIG. 8 , the bending angle θ is set at approximately 120 degrees, for example, but in the center of the knitted fabric, θ may be set at approximately 180 degrees.
FIG. 10 shows the determination of a correction vector relating to the stitch P 3 . The content of the processing is similar to that of FIG. 9 . In other words, a correction vector is generated in relation to the axis Axis in order to align the angle formed by the stitch P 1 and the stitch P 3 with θ.
FIGS. 11 and 12 show processing of the course direction bending angle, in which the processing model is similar to that of FIG. 9 . A symmetrical point to the stitch P 3 is set as P 3 ′ in relation to the subject stitch P 0 , whereupon the stitch P 1 and the stitch P 3 ′ are used to generate the axis Axis. Next, a point obtained by rotating the stitch P 4 by an amount corresponding to the default value φ of the course direction bending angle is set as P 4 ′, whereupon a correction vector is generated at an identical distance from the axis Axis to the stitch P 2 and at an identical orientation from the axis to P 4 ′.
In FIG. 12 , a similar axis Axis is generated, whereupon a point P 2 ′ is generated by rotating the stitch P 2 by an amount corresponding to −φ about the axis. The correction vector is then generated at an identical distance from the axis to the stitch P 4 and at an identical orientation from the axis to P 2 ′.
FIG. 13 shows a knitting procedure for a pin tuck pattern. A rib knit part is present in the center of the knitted fabric in FIG. 17 , and in this part, the number of knit stitches is far greater than the number of purl stitches. As a result, the knitted fabric bulges to the front side.
A pattern can be made to stand out by varying the size of each stitch using black and white thread. In this embodiment, a simulation can be performed such that the stitch size is modified according to the loop length of each stitch, and therefore this type of pattern can also be simulated.
In a simulation image of a glove, which relates to a tubular knitted fabric having a back side and a palm side, the default value of the course direction and wale direction bending angles is set at 120 degrees such that the bend at the ends of the tubular glove are represented naturally.
In one embodiment, a simulation of a knitting pattern for a pin tuck pattern can be produced where the three-dimensional deformation of the knitted fabric caused by the pin tuck is represented. The pin tuck is represented with a tendency to be pushed toward the lower side of the knitted fabric, but a simulation that emphasizes the bulging and projection of the pin tuck from the knitted fabric may also be performed. | An apparatus, method and simulation program for performing a realistic loop simulation of a knitted fabric using empirical rules during a loop simulation while keeping the calculation load within a feasible range to express three-dimensional bulges, curls and so on of a knitted fabric. | 3 |
FIELD OF THE INVENTION
The present disclosure relates to backlighting systems, which may be advantageously used with large high-performance liquid crystal displays. More specifically, the disclosure relates to backlighting systems that include multiple lightguides, and, optionally, various recycling enhancement structures.
BACKGROUND OF THE INVENTION
Liquid crystal displays (LCDs) are widely used in electronic display devices, such as computer monitors, handheld devices and televisions. Unlike cathode ray tube (CRT) displays, LCDs do not emit light and, thus, require a separate light source for viewing images formed on such displays. Ambient light illumination is sufficient for some applications, but with most large area and high performance LCDs, ambient light causes glare and is detrimental to readability. Thus, in order to improve readability, most large area and high performance LCDs include a source of light located behind the display, which is usually referred to as a “backlight.”
Presently, many popular systems for backlighting LCDs include direct-lit backlights, in which multiple lamps or a single serpentine-shaped lamp are arranged behind the display in the field of view of the user, and edge-lit backlights, in which the light sources are placed along one or more edges of a lightguide located behind the display, so that the light sources are out of the field of view of the user. In order to compete with CRT displays, large LCDs displays (e.g., greater than ˜20″ or 50 cm in diagonal) must have high luminance targets, e.g., about 500 nt or more. Such high luminance targets are currently met by direct-lit backlights for LCDs.
The use of conventional direct-lit backlights systems, however, has caused some concerns among manufacturers of large LCDs, such as LCD televisions. One concern is a discrepancy between the intended lifetimes of LCDs, which for most LCD television purchasers may be 10 to 20 years, and the lifetimes of individual lamps in the televisions' backlights, which are approximately 10,000 to 20,000 hours and usually at the lower end of this range. In particular, cold cathode fluorescent lamps (CCFLs), which are frequently used for backlighting, have varying lifetimes and aging characteristics. If one CCFL burns out in a conventional direct-lit backlight, the result will be a dark line directly across the display. In addition, the spatial color uniformity of a conventional direct-lit display suffers as each CCFL ages differently. Major LCD manufacturers and television set makers currently do not have a model for servicing LCD backlights that fail in either of these two modes.
Furthermore, light reaching the viewer from multiple sources in a conventional direct-lit backlight usually is not mixed as well as the light in edge-lit backlights. Nonetheless, despite this shortcoming as well as the uniformity and aging disadvantages of conventional direct-lit backlights, they are currently a popular choice for backlighting LCDs, e.g., LCD televisions, because they allow reaching luminance targets that are competitive with CRT displays. Although edge-lit-backlights would appear to be more advantageous in many respects, achieving desired levels of luminance with traditional edge-lit backlights has remained a challenge. One difficulty has been arranging a large enough number of light sources at an edge of a single lightguide to provide sufficient optical power to reach the target luminance. Other difficulties include enhancement film warping in traditional backlights, e.g., due to high thermal gradients and handling problems.
Thus, there remains a need in the field of backlights for large high-performance LCDs for backlighting systems that are capable of achieving high luminance targets and are more efficient. In addition, there remains a need for backlighting systems for large high-performance LCDs that overcome other shortcomings of the currently available backlights described above.
SUMMARY
These and other shortcomings of the presently known backlights for large high-performance LCDs are addressed by the inventors of the present disclosure by providing multiple-lightguide backlighting systems as disclosed and claimed herein. Such systems may be advantageously used with a variety of devices, including LCD televisions, LCD monitors, point of sale devices, and other suitable devices. In addition to allowing to achieve high output luminances, the present disclosure mitigates the risks of using variable lifetime light sources, so that burnout or aging of an individual light source would not be catastrophic to the display viewing quality. Thus, if an individual light source ages or burns out in a multiple-lightguide system according to an embodiment of the present disclosure, the effect on spatial brightness and color uniformity will be relatively insignificant due to the enhanced light mixing.
The present disclosure eliminates the need for a thick diffuser plate traditionally used in direct-lit backlights to hide individual sources from the viewer, thus providing additional gains in brightness. The present disclosure also eliminates the need for a structured reflector traditionally used in direct-lit backlights, resulting in cost reductions and increased ease of manufacturing. In addition, light extracted directly from the top lightguide could be allowed to exit at a wide range of angles, which would enhance off-axis viewability of the display. Moreover, the present disclosure makes possible inclusion of additional features for preventing warp and physical damage to various recycling enhancement structures that may be used in exemplary embodiments of the present disclosure.
Thus, the present disclosure is directed to backlighting systems, which in one exemplary embodiment include first and second lightguides, at least one light source optically connected to an edge of the first lightguide and at least one light source optically connected to an edge of the second lightguide for supplying light into their respective interiors. In some embodiments, the backlighting systems of the present disclosure include an extractor disposed at a surface of the second lightguide for diffuse extraction of light from the interior of the second lightguide. In such exemplary embodiments, at least a portion of the light supplied into the interior of the second lightguide and then diffusely extracted therefrom enters the interior of the first lightguide through a substantially optically clear surface.
Such backlighting systems may further include a first recycling enhancement structure disposed at a surface of the first lightguide, which may include a reflective polarizer, a reflective polarizer and a diffuser, or a reflective polarizer and a prismatic structure. The diffuser may be spatially graded. Preferably, the first recycling enhancement structure is attached to a surface of the first lightguide. Alternatively or additionally, the backlighting systems of the present disclosure may include a second recycling enhancement structure disposed between the first lightguide and the second lightguide, which may include a prismatic structure. Preferably, the second recycling enhancement structure is attached to a surface of the first lightguide.
Other embodiments of the backlighting systems of the present disclosure include first and second lightguides, at least one light source optically connected to an edge of the first lightguide and at least one light source optically connected to an edge of the second lightguide for supplying light into their respective interiors. Such exemplary embodiments also include a second recycling enhancement structure disposed between the first lightguide and the second lightguide.
The second recycling enhancement structure may include a prismatic structure. The prismatic structure preferably includes a plurality of prisms having apexes pointing generally away from the second lightguide. In the appropriate embodiments, the second recycling enhancement structure may include a first surface defining a plurality of prisms substantially symmetrical about a first horizontal axis and having apexes pointing generally away from the second lightguide and a second surface defining a plurality of prisms substantially symmetrical about a second horizontal axis and having apexes pointing generally away from the second lightguide. The first axis may be generally orthogonal to the second axis. Preferably, the second recycling enhancement structure is attached to a surface of the first lightguide.
The backlighting systems constructed according to the present disclosure may also include a first recycling enhancement structure disposed at a surface of the first lightguide. The first recycling enhancement structure may include a reflective polarizer, a reflective polarizer and a diffuser, or a reflective polarizer and a prismatic structure. Preferably, the first enhancement structure is attached to a surface of the first lightguide.
In the appropriate exemplary embodiments of the present disclosure, the first and second lightguides each comprise two opposing edges, at least one light source is optically connected to each of said edges, and the opposing edges of the first lightguide are not aligned with the opposing edges of the second lightguide. Alternatively, the first and second lightguides each comprise two adjacent edges, at least one light source is optically connected to each of said edges, and the adjacent edges of the first lightguide are not aligned with the adjacent edges of the second lightguide.
The present disclosure is also directed to backlighting systems, which include first and second lightguides, a plurality of light sources optically connected to a first edge of the first lightguide, a plurality of light sources optically connected to a second edge of the first lightguide, a plurality of light sources optically connected to a first edge of the second lightguide, and a plurality of light sources optically connected to a second edge of the second lightguide. In some embodiments, the backlighting systems of the present disclosure include an extractor disposed at a surface of the second lightguide for diffuse extraction of light from the interior of the second lightguide. In such exemplary embodiments, at least a portion of the light supplied into the interior of the second lightguide and then diffusely extracted therefrom enters the interior of the first lightguide through a substantially optically clear surface. Such backlighting systems may further include a first recycling enhancement structure disposed at a surface of the first lightguide, which may include a reflective polarizer, a reflective polarizer and a diffuser, or a reflective polarizer and a prismatic structure. The diffuser may be spatially graded. Preferably, the first recycling enhancement structure is attached to a surface of the first lightguide.
Alternatively or additionally, these exemplary embodiments may include a second recycling enhancement structure disposed between the first lightguide and the second lightguide. The second recycling enhancement structure may include a prismatic structure. The prismatic structure preferably includes a surface defining a plurality of prisms having apexes pointing generally away from the second lightguide. In the appropriate embodiments, the second recycling enhancement structure may include a first surface defining a plurality of prisms substantially symmetrical about a first horizontal axis and having apexes pointing generally away from the second lightguide and a second surface defining a plurality of prisms substantially symmetrical about a second horizontal axis and having apexes pointing generally away from the second lightguide. The first axis may be generally orthogonal to the second axis. Preferably, the second recycling enhancement structure is attached to a surface of the first lightguide.
Furthermore, in the appropriate embodiments of the present disclosure, at least one of the first lightguide and the second lightguide may have variable thickness, and at least one lightguide may include first and second wedge portions. The extractor disposed at a surface of the second lightguide may be spatially graded. Additionally or alternatively, substantially optically clear surface extraction structures may be disposed on the surface of the first lightguide that faces the second lightguide. The backlighting systems of the present disclosure may also include a reflector sheet disposed next to the surface of the second lightguide that faces away from the first lightguide and a diffuser sheet disposed next to the surface of the second lightguide that faces away from the first lightguide.
These and other aspects of the backlighting systems of the subject invention will become more readily apparent to those having ordinary skill in the art from the following detailed description together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
So that those having ordinary skill in the art to which the subject invention pertains will more readily understand how to make and use the subject invention, exemplary embodiments thereof will be described in detail below with reference to the drawings, wherein:
FIG. 1 is a schematic cross-sectional view of a presently available direct-lit backlight for LCD televisions;
FIG. 2 is a schematic cross-sectional view of an exemplary embodiment of a backlighting system according to the present disclosure;
FIGS. 2A and 2B illustrate alternative ways of arranging light sources at the edges of generally rectangular lightguides;
FIG. 3 is a schematic cross-sectional view of another exemplary embodiment of a backlighting system according to the present disclosure, illustrating the use of a spatially graded diffuser;
FIG. 4 is a schematic cross-sectional view of another exemplary embodiment of a backlighting system according to the present disclosure, illustrating the use of a variable thickness lightguide;
FIG. 5 is a schematic cross-sectional view of another exemplary embodiment of a backlighting system according to the present disclosure;
FIG. 6 is a schematic cross-sectional view of an exemplary configuration for testing some of the concepts of the present disclosure;
FIGS. 7A-C show data illustrating properties of light extracted from the top lightguide, where the top lightguide is a bare wedge ( FIG. 7A ), a wedge laminated with DBEF-M ( FIG. 7B ), or a wedge laminated with DRPF ( FIG. 7C );
FIGS. 8A-F show data representing output polarization of DRPF-laminated lightguide;
FIGS. 9A-F show data representing output polarization of DBEF-M-laminated lightguide;
FIG. 10A shows a gain profile of a lightguide system with a loose sheet of DRPF;
FIG. 10B shows a gain profile of a lightguide system with a laminated sheet of DRPF;
FIG. 10C shows a gain profile of a lightguide system with a loose sheet of DBEF-M; and
FIG. 10D shows a gain profile of a lightguide system with a laminated sheet of DBEF-M.
DETAILED DESCRIPTION
FIG. 1 illustrates the structure and components of a traditional direct-lit backlight 10 , such as those presently used in LCD televisions. The traditional backlight 10 includes an array of light bulbs 15 , typically CCFLs, and a shaped reflector 17 located behind the array of light bulbs 15 for directing more light toward a viewer. A thick diffuse plate 18 is usually placed over the array of light bulbs 15 to diffuse light from the individual bulbs, e.g., CCFLs, in order to hide them from the viewer. A typical diffuser plate 18 has a large amount of absorption associated with it, as well as a large amount of back scattering, the effects of which grow exponentially if light-recycling enhancement films (described below) are added to the backlight. To further aid in hiding individual light bulbs from the viewer, diffuser plates have been patterned, which resulted in additional losses of light.
The traditional backlight 10 further includes a thin diffuser sheet 16 and a layer of enhancement film 14 having prismatic surface structures, such as Vikuiti™ Brightness Enhancement Film BEF, available from 3M Company. The enhancement film 14 refracts light within a certain angle toward the viewer. Light outside that angle is “recycled,” i.e., reflected back into the backlight 10 , where it travels within the system until reaching the proper angle for exiting the system. In addition, the traditional backlight 10 includes a layer of reflective polarizer 12 placed over the enhancement film 14 . The reflective polarizer 12 is usually a multilayer reflective polarizer, such as Vikuiti™ Dual Brightness Enhancement Film (DBEF), also available from 3M Company. The reflective polarizer 12 transmits light with a predetermined polarization, while reflecting light with a different polarization into the backlight 10 where the polarization state is altered and the light is fed back to the reflective polarizer 12 . This process is also referred to as “recycling.”
FIG. 2 shows a schematic cross-sectional view of a backlighting system 100 constructed according to an exemplary embodiment of the present disclosure. The backlighting system 100 includes a first lightguide 130 and a second lightguide 140 . In the exemplary embodiment shown in FIG. 2 , pairs of light sources 165 a and 165 b are placed at the edges 132 a and 132 b of the first lightguide 130 , so that at least a portion of the light emanating from the sources 165 a , 165 b is coupled into the interior of the lightguide 130 and propagates along its length by reflecting from the surfaces 130 a and 130 b , e.g., by total internal reflection. Lamp cavity reflectors 156 a , 156 b may be provided as illustrated in FIG. 2 , for increasing coupling efficiency from the sources 165 a , 165 b into the interior of the lightguide 130 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors 156 a , 156 b may vary.
Referring further to FIG. 2 , in the exemplary backlighting system 100 , pairs of light sources 185 a and 185 b are placed at the edges 142 a and 142 b of the second lightguide 140 , so that at least a portion of the light emanating from the sources 185 a , 185 b is coupled into the interior of the lightguide 140 and propagates along its length by reflecting from the surfaces 140 a and 140 b , e.g., by total internal reflection. Lamp cavity reflectors 176 a , 176 b , similar to the lamp cavity reflectors 156 a and 156 b , may be provided as illustrated in FIG. 2 for increasing coupling efficiency from the sources 185 a , 185 b into the interior of the lightguide 140 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors 176 a , 176 b may also vary.
Although the exemplary backlighting system 100 illustrated in FIG. 2 shows pairs of light sources 165 a , 165 b placed at the edges 132 a , 132 b of the lightguide 130 and pairs of light sources 185 a , 185 b placed at the edges 142 a , 142 b of the lightguide 140 , the present disclosure also contemplates using one, three or more light sources at an edge of the lightguide 130 and one, three or more light sources at one or more edges of the lightguide 140 . In addition, although for ease of illustration light sources 165 a and 165 b are shown to be aligned with the light sources 185 a and 185 b , the present disclosure contemplates placing light sources at any one or more edges of each lightguide, as desired for a specific application. For example, FIGS. 2A and 2B , illustrate two exemplary ways of arranging light sources 135 a ′, 135 a ″, 145 a ′, 145 a ″ and 135 b ′, 135 b ″, 145 b ′, 145 b ″ at the edges of generally rectangular lightguides 130 a , 140 a and 130 b , 140 b respectively. In FIG. 2A , light sources 135 a ′and 135 a ″ are disposed at the opposing edges 125 a ′ and 125 a ″ of the lightguide 130 a and light sources 145 a ′ and 145 a ″ are disposed at the opposing edges 155 a ′ and 155 a ″ of the lightguide 140 a . In this exemplary embodiment, each of the opposing edges 125 a ′ and 125 a ″ is not aligned with any of the opposing edges 155 a ′ and 155 a ′. In FIG. 2B , light sources 135 b ′ and 135 b ″ are disposed at the adjacent edges 125 b ′ and 125 b ″ of the lightguide 130 b and light sources 145 b ′ and 145 b ′ are disposed at the adjacent edges 155 b ′ and 155 b ″ of the lightguide 140 b . In this exemplary embodiment, each of the adjacent edges 125 b ′ and 125 b ″ is not aligned with any of the adjacent edges 155 b ′ and 155 b″.
Light sources suitable for use with embodiments of the present disclosure include any source that emits light, such as a fluorescent lamp (e.g., CCFL), a hot cathode fluorescent lamp (HCFL), an incandescent lamp, an electroluminescent light source, a phosphorescent light source, an external electrode fluorescent lamp, a light emitting diode (LED), including organic LEDs (OLEDs), an array of LEDs, any other suitable light source(s), or any appropriate number or combination thereof.
The number and type of lightguides may also vary. For example, three or more lightguides may be used in accordance with the present disclosure and any one or more of the constituent lightguides may be hollow. Increasing the number of lightguides in backlighting systems according to exemplary embodiments of the present disclosure would lead to corresponding increases in weights and thicknesses of displays. However, most manufacturers of large panel LCDs typically consider display thickness and weight to be secondary concerns. Lifetime, brightness, spatial uniformity, ease of assembly, and reduction in warp of enhancement films are usually considered to be more important.
The number and type of light sources arranged at an edge of a lightguide, e.g., 130 or 140 , as well as the number, dimensions and type of lightguides will depend on the specific application and luminance target, as well as practical considerations such as the size of the specific source as compared to the dimensions of the lightguide. For example, assuming that lightguides 130 and 140 have about the same thicknesses as those typically seen in traditional single-lightguide edge-lit displays, up to six bulbs of typical CCFLs may be used per lightguide (e.g., three bulbs at each of the edges 132 a , 132 b , 142 a , and 142 b ). Thus, a 29″ direct-lit LCD television backlight having 12 light bulbs can be replaced with a two-lightguide system illustrated in FIG. 2 , with three bulbs arranged at each lightguide edge (e.g., 132 a , 132 b , 142 a and 142 b ). A 32″ direct-lit LCD television with 16 light bulbs would require a three-lightguide system to make it completely edge-lit in order to produce comparable luminance.
Referring further to FIG. 2 , the backlighting system 100 may include a first recycling enhancement structure 112 disposed at a surface of the first lightguide 130 . In the context of the present disclosure, “a recycling enhancement structure” may be any structure that is capable of “recycling” light in a manner similar or equivalent to the enhancement films 12 and 14 , described with reference to FIG. 1 . Preferably, the first recycling enhancement structure 112 is disposed at the surface 130 a and includes a reflective polarizer, such as a multilayer reflective polarizer Vikuiti™ Dual Brightness Enhancement Film (DBEF), available from 3M Company. Most preferably, the first recycling enhancement structure 112 also includes a diffuser, which may be integrated within the reflective polarizer or be included as a separate component, such as a matte surface or a layer of pressure sensitive adhesive (PSA). One function of the diffuser is the randomization of the polarization and direction of the light reflected by the reflective polarizer back into the backlighting system 100 . Exemplary components suitable for use within the first recycling enhancement structure 112 include Vikuiti™ Diffuse Reflective Polarizer Film (DRPF) and Vikuiti™ Dual Brightness Enhancement Film-Matte (DBEF-M), both available from 3M Company.
The first recycling enhancement structure 112 preferably is attached to a surface of the first lightguide 130 , e.g., surface 130 a . The first recycling enhancement structure 112 may be attached to a surface of the first lightguide 130 by lamination, molding the enhancement structure 112 or any of its constituent components into the lightguide or by any suitable bonding technique. If the first recycling enhancement structure 112 includes a matte surface, e.g., as in DBEF-M, the first recycling enhancement structure 112 preferably is attached to the lightguide 130 so that the matte surface faces the surface 130 a . In exemplary embodiments of the present disclosure, in which the first recycling enhancement structure 112 is attached to the first lightguide 130 , light may be extracted from the interior of the first lightguide 130 through its interactions with the first recycling enhancement structure 112 . For example, if DRPF or DBEF-M is included into the structure 112 , light is diffused by either of these films and it is either transmitted to the LCD in the proper polarization state or scattered back into the backlight 100 , where it can be recycled as explained above. Alternatively, DBEF may be attached to a surface of the first lightguide 130 with a layer of PSA. In that case, PSA would also facilitate the extraction of light from the interior of the first lightguide 130 .
In appropriate exemplary embodiments of the present disclosure, both DBEF and DRPF may be included into the first recycling enhancement structure 112 and preferably attached, e.g., laminated, to the surface 130 a of the lightguide 130 . In that case, the polarization axes of both reflective polarizers, i.e., DBEF and DRPF should be aligned. As a result, DRPF will facilitate extraction of light from the lightguide 130 , while DBEF will enhance the contrast. Alternatively, BEF or another suitable prismatic film or structure may be used in combination with a reflective polarizer, e.g., DBEF, as a part of the first recycling enhancement structure 112 . BEF would facilitate light extraction, while DBEF would ensure that light exits the backlight 100 with the appropriate polarization.
Additionally or alternatively, the backlighting system 100 illustrated in FIG. 2 may include a second recycling enhancement structure 114 , which may be disposed between the first lightguide 130 and the second lightguide 140 . Preferably, the second recycling enhancement structure 114 includes prismatic structures, e.g., prismatic structured film, that would aid in redirecting and recycling light to increase on-axis brightness of the backlight 100 by refracting toward the viewer light within a certain angle and reflecting back light outside that angle. One example of such prismatic structured films suitable for use within the second recycling enhancement structure 114 is Vikuiti™ Brightness Enhancement Film (BEF), available from 3M Company. The second recycling enhancement structure 114 also may include prismatic structures oriented so that the prism apexes are facing generally away from the lightguide 130 .
In the appropriate exemplary embodiments of the present disclosure, two BEFs or similar prismatic films or structures may be used in the second recycling enhancement structure 114 . In such exemplary embodiments, the directions of the prismatic films' grooves preferably are crossed, and a thin layer of adhesive joins the films so that only small portions of the prismatic structures are immersed into the adhesive. The second recycling enhancement structure 114 preferably is attached, e.g., laminated, molded or bonded using any other suitable technique, to the surface 130 b of the lightguide 130 . This feature would create added extraction from the first lightguide 130 and reduce warping of the second recycling enhancement structure 114 , which may occur due to temperature variations, handling and other causes.
Placing an extractor 143 , preferably a diffuse extractor, at a surface of the lightguide 140 may facilitate light extraction from the second lightguide 140 . FIG. 2 illustrates the use of such an extractor 143 , which in this exemplary embodiment includes an array of dots disposed on the surface 140 b of the lightguide 140 . Preferably, the pattern of dots is optimized to compensate for potential spatial non-uniformities of light extraction from the entire backlighting system 100 . For example, the dot pattern may be adjusted so that more light is extracted toward the center of the lightguide 140 by gradually increasing the size of dots toward the center of the lightguide 140 .
The backlighting system 100 may further include a diffuser sheet 116 and a reflector sheet 127 . The diffuser sheet primarily serves to increase spatial uniformity of the light exiting the second lightguide 140 , as well as to aid in randomizing polarization of the light reflected back into the backlight 100 . The reflector sheet 127 may further increase efficiency of the backlighting system 100 by reflecting back light that escapes through the side 140 b of the lightguide 140 , so that the light may be directed toward the viewer and/or recycled.
FIG. 3 is a schematic cross-sectional view of a backlighting system 200 constructed according to another exemplary embodiment of the present disclosure. The backlighting system 200 includes a first lightguide 230 and a second lightguide 240 . Pairs of light sources 265 a and 265 b are placed at the edges 232 a and 232 b of the first lightguide 230 , so that at least a portion of the light emanating from the sources 265 a , 265 b is coupled into the interior of the lightguide 230 and propagates along its length by reflecting from the surfaces 230 a and 230 b , e.g., by total internal reflection. Lamp cavity reflectors 256 a , 256 b may be provided for increasing coupling efficiency from the sources 265 a , 265 b into the interior of the lightguide 230 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors 256 a , 256 b may vary.
Referring further to FIG. 3 , in the exemplary backlighting system 200 , pairs of light sources 285 a and 285 b are placed at the edges 242 a and 242 b of the second lightguide 240 , so that at least a portion of the light emanating from the sources 285 a , 285 b is coupled into the interior of the lightguide 240 and propagates along its length by reflecting from its surfaces 240 a and 240 b , e.g., by total internal reflection. Lamp cavity reflectors 276 a , 276 b , similar to the lamp cavity reflectors 256 a and 256 b , may be provided for increasing coupling efficiency from the sources 285 a , 285 b into the interior of the lightguide 240 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors 276 a , 276 b may also vary. As it has been explained in reference to the exemplary embodiments illustrated in FIG. 2 , the number, type and configuration of light sources and lightguides may vary as well.
Referring further to FIG. 3 , the backlighting system 200 may include a first recycling enhancement structure 212 disposed at a surface of the first lightguide 230 . Preferably, the first recycling enhancement structure 212 is disposed at the surface 230 a and includes a reflective polarizer 212 b , such as DBEF. Most preferably, the first recycling enhancement structure further includes a diffuser 212 a , such as a loaded PSA structure, which also may be used to attach the reflective polarizer to a surface, e.g., surface 230 a , of the first lightguide 230 . As illustrated in FIG. 3 , the diffuser 212 a may be spatially graded to improve the overall uniformity of the output from the backlighting system 200 . The backlighting system 200 may also include optically clear surface extraction features 245 , such as step-wedge structures disposed on the surface 230 b , which would facilitate extraction of light from the first lightguide 230 . Those of ordinary skill in the art will readily recognize that such surface extraction features 245 may be used as appropriate in other exemplary embodiments of the present disclosure.
The remainder of the backlighting system 200 may have a structure similar to that of the embodiments illustrated in FIG. 2 or a different suitable structure. For example, the backlighting system 200 may include a second recycling enhancement structure 214 , which may be disposed between the first lightguide 230 and the second lightguide 240 . Preferably, the second recycling enhancement structure 214 includes prismatic structures, e.g., prismatic structured film such as BEF, which redirect and recycle light to increase on-axis output brightness of the backlighting system 200 by refracting toward the viewer light within a certain angle and reflecting back light outside that angle. Similar to the backlighting system 100 , the backlighting system 200 may further include a diffuser sheet 216 and a reflector sheet 227 .
Light extraction from the second lightguide 240 may be accomplished by placing an extractor 243 , preferably a diffuse extractor, at a surface of the lightguide 240 . FIG. 3 illustrates the use of such an extractor 243 , which in this exemplary embodiment includes an array of dots disposed on the surface 240 b of the lightguide 240 . Preferably, the pattern of dots is optimized to compensate for potential spatial non-uniformities of light extraction from the entire backlighting system 200 . For example, the dot pattern may be adjusted so that more light is extracted toward the center of the lightguide 240 by gradually increasing the size of dots toward the center of the lightguide 240 .
FIG. 4 illustrates a backlighting system 300 constructed according to another exemplary embodiment of the present disclosure. The backlighting system 300 includes a first lightguide 330 and a second lightguide 340 . As it has been explained in reference to other exemplary embodiments, pairs of light sources 365 a and 365 b are placed at the edges 332 a and 332 b of the first lightguide 330 , and pairs of light sources 385 a and 385 b are placed at the edges 342 a and 342 b of the second lightguide 240 . Preferably, lamp cavity reflectors 356 a , 356 b and 376 a , 376 b are provided for increasing coupling efficiency from the sources 365 a , 365 b and 385 a , 385 b into the lightguides 330 and 340 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors may vary. The number, type and configuration of light sources and the number and configuration of lightguides may vary as well.
In the exemplary backlighting system 300 , the first lightguide 330 may include two wedge lightguides 336 a and 336 b joined at a juncture or seam 336 c , or a single lightguide molded so that the surface 330 a is generally flat while the surface 330 b has a cross-section approximating the shape of an inverted V, with the thickness of the lightguide 330 tapering away from the light sources, as illustrated in FIG. 4 . A first recycling enhancement structure 312 may be disposed at a surface of the first lightguide 330 . Preferably, the first recycling enhancement structure 312 is disposed at the surface 330 a and includes a reflective polarizer, such as DBEF. Most preferably, the first recycling enhancement structure 312 also includes a diffuser, which may be integrated within the reflective polarizer or be included as a separate component, such as a matte surface or a layer of PSA. Examples of structures suitable for use within the first recycling enhancement structure 312 in exemplary embodiments of the present disclosure include DRPF and DBEF-M.
The first recycling enhancement structure 312 preferably is attached to the surface 330 a of the first lightguide 330 , e.g., by lamination, molding the enhancement structure 312 or any of its constituent components into the lightguide or by any suitable bonding technique. Extraction of light from the first lightguide 330 in such exemplary embodiments may be achieved by total internal reflection failure and interactions with the attached first recycling enhancement structure 312 .
The remainder of the backlighting system constructed according to this exemplary embodiment may have a structure similar to the embodiments illustrated in FIGS. 2 and 3 , or a different suitable structure. For example, the backlighting system 300 may include a second recycling enhancement structure 314 disposed between the first lightguide 330 and the second lightguide 340 . Preferably, the second recycling enhancement structure 314 includes prismatic structures, e.g., prismatic structured film such as BEF, that redirect and recycle light to increase on-axis brightness of the backlight 300 by refracting toward the viewer light within a certain angle and reflecting back light outside that angle. In the appropriate exemplary embodiments, the second recycling enhancement structure 314 may include prismatic structures having prism apexes that face generally away from the light guide 330 . Similar to the backlighting system 100 , the backlighting system 300 may further include a diffuser sheet 316 and a reflector sheet 327 .
Light extraction from the second lightguide 340 may be accomplished by placing an extractor 343 , preferably a diffuse extractor, at a surface of the lightguide 340 . The extractor 343 may include an array of dots disposed on the surface 340 b of the lightguide 340 . Preferably, the pattern of dots is optimized to compensate for potential spatial non-uniformities of light extraction from the entire backlighting system 300 . For example, if two wedge lightguides 336 a and 336 b are used to form the lightguide 330 , extraction of light from the second lightguide 340 may be adjusted to hide the juncture or seam 336 c from the viewer by a flood of light. This may be accomplished by increasing the size of dots in a dot pattern toward the center of the lightguide 340 .
FIG. 5 shows a schematic cross-sectional view of a backlighting system 400 according to another exemplary embodiment of the present disclosure. The backlighting system 400 includes a first lightguide 430 and a second lightguide 440 . As it has been explained in reference to other exemplary embodiments, pairs of light sources 465 a and 465 b are placed at the edges 432 a and 432 b of the first lightguide 430 , and pairs of light sources 485 a and 485 b are placed at the edges 442 a and 442 b of the second lightguide 440 . Lamp cavity reflectors 456 a , 456 b and 476 a , 476 b may be provided for increasing coupling efficiency from the sources 465 a , 465 b and 485 a , 485 b into the lightguides 430 and 440 . As will be understood by those of ordinary skill in the art, shape and structure of the reflectors may vary. The number, type and configuration of light sources and lightguides may vary as well.
Referring further to FIG. 5 , the backlighting system 400 may include a recycling enhancement structure 426 disposed at the surface 430 a of the first lightguide 430 . Preferably, the recycling enhancement structure 426 includes a reflective polarizer, such as DBEF, and prismatic structures, e.g., a prismatic structured film such as BEF. The prismatic structures may be introduced into the backlight 400 by appropriately molding the first lightguide 430 , laminating a sheet of prismatic film onto the surface 430 a , or by any other suitable technique. The reflective polarizer, e.g., DBEF, also may be attached to the lightguide 430 , e.g., by lamination, molding or another suitable bonding technique, preferably over the prismatic structures. Variations may be introduced into the recycling enhancement structure 426 , and particularly into the prismatic structures, to enhance extraction of light from the first lightguide 430 as well as to increase off-axis brightness. See, e.g., U.S. Pat. No. 6,354,709, the disclosure of which is incorporated by reference herein to the extent not inconsistent with the present disclosure. In the appropriate exemplary embodiments, the recycling enhancement structure may include prismatic structures having prism apexes that face generally forward the first lightguide 430 .
The second lightguide 440 may include an extractor 443 , preferably a diffuse extractor, disposed at a surface of the lightguide 440 . As in other embodiments described herein, the extractor 443 may be disposed on the surface 440 b of the lightguide 440 and may include an array of dots. Preferably, the pattern of dots is optimized to compensate for potential spatial non-uniformities of light extraction from the entire backlighting system 400 . The backlighting system 400 may further include a diffuser sheet 416 , which would aid in hiding the diffuse extractor 443 from the viewer and randomizing polarization of recycled light, and a reflector sheet 427 .
Series of experiments were conducted to test various aspects of exemplary embodiments of the present disclosure. FIG. 6 illustrates a testing configuration 700 for exemplary embodiments of the present disclosure. The testing configuration 700 includes a bottom lightguide 740 , illuminated by two CCFL light source assemblies 780 a , 780 b , with a reflector 727 disposed below the lightguide 740 and a diffuser sheet 716 disposed over the lightguide 740 . Crossed BEFs 714 a , 714 b were also included into the testing configuration 700 and positioned over the diffuser sheet 716 . The top lightguide 730 in this configuration was a wedge lightguide laminated with strips of DBEF-M (diffuse side toward lightguide) and DRPF, designated as 712 and located side-by-side. The light source 760 for illuminating the top lightguide 730 was an incandescent fiber line source. An absorbing polarizer 772 was placed over the top lightguide 730 so that it could be aligned or anti-aligned with the reflective polarizer or completely removed.
Conoscopic measurements were then taken using ELDIM EZContrast160. All measurements were made at a constant distance from the fiber source to eliminate effects of down-wedge spatial non-uniformities. Performance improvements were seen despite the fact that the output luminance of the wedge lightguide 730 and fiber source 760 was more than an order of magnitude smaller than that of the bottom lightguide 740 illuminated by the CCFL source assemblies 780 a and 780 b.
FIGS. 7A-7C show results of the first set of measurements, illustrating properties of light extracted from the top lightguide 730 laminated with the reflective polarizers 712 . The absorbing polarizer 772 was not used in these measurements. FIG. 7A represents light extraction form the bare top lightguide 730 (no reflective polarizers), FIG. 7B represents light extraction from the top lightguide 730 laminated with DBEF-M, and FIG. 7C represents light extraction from the top lightguide 730 laminated with DRPF. Extraction from the bare lightguide 730 occurs by total internal reflection failure. The data represented in FIGS. 7A-7C demonstrate effectiveness of light extraction from the top lightguide 730 via interactions with the laminated DBEF-M and DRPF. FIGS. 8A-E and 9 A-E show results of measurements comparing polarization content of the extracted light to that of light transmitted through the reflective polarizer 712 . FIG. 8 shows the data for DRPF laminated onto the top lightguide 730 and FIG. 9 shows the data for DBEF-M laminated onto the top lightguide 730 . Measurements corresponding to FIGS. 8A , 8 D, 9 A and 9 D were made without the absorbing polarizer 772 , measurements corresponding to FIGS. 8B , 8 E, 9 B and 9 E were made with the absorbing polarizer 772 aligned with the pass axis of the reflective polarizer 712 , and FIGS. 8C , 8 F, 9 C and 9 F were made with the absorbing polarizer 772 anti-aligned with the pass axis of the reflective polarizer 712 . In each configuration, two measurements were made: 1) fiber source turned on and CCFL sources turned off ( FIGS. 8A , 8 B, 8 C, 9 A, 9 B and 9 C), and 2) fiber source turned off and CCFL sources turned on ( FIGS. 8D , 8 E, 8 F, 9 D, 9 E and 9 F). Overall, the data shown in FIGS. 8A-E and 9 A-E demonstrate that light extracted from the top lightguide 730 is polarized predominantly with the same orientation as the light transmitted through the reflective polarizer 712 .
FIGS. 10A-D show measurements performed to verify that the gain of the reflective polarizer 712 in the system 700 is not diminished because it is laminated to the top lightguide 730 . First, the top lightguide was removed and the reflective polarizer was positioned at 712 ′ in FIG. 6 . Measurements were then made with a loose sheet of DBEF-M and then with the same lot of DBEF-M laminated to the top lightguide 730 (the fiber source was not turned on). The gain due to both the loose sheet and laminated DBEF-M was then computed by taking a ratio of the measurements with DBEF-M to the measurement with DBEF-M removed. The procedure was then repeated for DRPF. FIGS. 10A-D show the results of these gain measurements. As can be seen, the gain for the systems with laminated reflective polarizers was slightly higher than that for the loose sheet versions. This occurred due to the fact that an air interface had been removed and some of the diffusivity of the samples had been wetted-out against the lightguide.
Thus, the backlighting systems constructed according to the present disclosure allow achieving high output luminances and address various problems encountered with the presently known backlights for LCDs. For example, the present disclosure mitigates the risks of using variable lifetime light sources, so that burnout or aging of an individual light source would not be catastrophic to the display viewing quality. Thus, if an individual light source ages or burns out in a multiple-lightguide system according to an embodiment of the present disclosure, the effect on spatial brightness and color uniformity will be relatively insignificant due to the enhanced light mixing.
The present disclosure eliminates the need for a thick diffuser plate traditionally used in direct-lit backlights to hide individual sources from the viewer, thus providing additional gains in brightness. The present disclosure also eliminates the need for a structured reflector surface traditionally used in single-cavity direct-lit backlights, resulting in cost reduction and increased ease of manufacturing. In addition, light extracted directly from the top lightguide is likely to exit at a wide range of angles, which would enhance off-axis viewability of the display. Moreover, the present disclosure makes possible inclusion of additional features for preventing warp and physical damage to various recycling enhancement structures, which may be used in exemplary embodiments of the present disclosure.
Although the backlighting systems of the present disclosure have been described with reference to specific exemplary embodiments, those of ordinary skill in the art will readily appreciate that changes and modifications may be made thereto without departing from the spirit and scope of the present invention. For example, the number, type and configuration of light sources, lightguides, and recycling enhancement structures used in exemplary embodiments of the present disclosure may vary. Any of the lightguides used in exemplary embodiments of the present disclosure may be a hollow lightguide or have another suitable structure. See, e.g., U.S. patent application entitled “Hybrid Lightguide Backlight,” Attorney Case No. 59399US002, filed concurrently herewith and incorporated by reference herein to the extent not inconsistent with the present disclosure.
In addition, it will be understood by those of ordinary skill of the art, that the terms “prismatic structures,” “prismatic films” and “prisms” encompass those having structural and other variations, such as those described in U.S. Pat. No. 6,354,709, as well as prismatic structures having rounded peaks. Furthermore, although the present disclosure is particularly advantageous for use in large area, high luminance applications typically associated with LCD televisions, it could also encompass LCD monitors and point of sale devices. | The present disclosure is directed to backlighting systems, which include first and second lightguides, at least one light source optically connected to an edge of the first lightguide and at least one light source optically connected to an edge of the second lightguide for supplying light into their respective interiors. In the appropriate exemplary embodiments, the backlighting systems of the present disclosure include an extractor disposed at a surface of the second lightguide for diffuse extraction of light from the interior of the second lightguide. In such exemplary embodiments, at least a portion of the light supplied into the interior of the second lightguide and then diffusely extracted therefrom enters the interior of the first lightguide through a substantially optically clear surface. In some exemplary embodiments, the backlighting systems of the present disclosure include recycling enhancement structures, which may be attached to the first lightguide. | 6 |
BACKGROUND
[0001] 1. Technical Field
[0002] The invention concerns an apparatus and a process for welding steel sheets for producing a rotor blade of a wind power installation. The invention also concerns a process and an apparatus for the manufacture of a rotor blade of a wind power installation. In addition the invention concerns a wind power installation and a rotor blade of a wind power installation. Furthermore the invention concerns an apparatus and a process for the hot forming of a steel sheet of a rotor blade of a wind power installation. In addition the invention concerns an apparatus and a process for cutting steel sheets to size for a rotor blade of a wind power installation.
[0003] 2. Description of the Related Art
[0004] Wind power installations are known nowadays in particular in the form of so-called horizontal-axis wind power installations. In that case an aerodynamic rotor having at least one and usually three rotor blades rotates about a substantially horizontal axis. In that case the rotor blades are of an aerodynamic configuration and are moved by the wind so that said rotary movement takes place, which can then be converted into electrical energy by an electric generator.
[0005] Modern wind power installations have rotor blades which are of increasingly greater size and in particular greater length. In the meantime rotor blades of lengths of about 60 m, of a depth of up to over 8 m and a thickness of up to over 3 m are already known. A connecting flange of such a rotor blade for fixing a rotor hub also nowadays is already of a diameter of over 3.5 m. For rotor blades of such orders of magnitude it may be appropriate for them also to be at least portion-wise made from steel.
[0006] Steel production is known from many other technological areas such as for example ship building, but transfer to the manufacture of a rotor blade of a wind power installation is basically not possible because of the very special demands of rotor blade manufacture. In this connection mention is to be made in particular but not definitively of the fact that, in rotor blade manufacture, the aim in spite of everything is to implement a lightweight structure, insofar as that is at all possible when using steel. In addition it is to be noted that a rotor blade of a wind power installation is exposed to permanently changing loads. In that respect there is a change not only in loading amplitude but also loading direction and in particular upon rotary movement of the rotor the force of gravity can involve an ongoing change between tensile and compression loadings. In that respect a rotor blade is a long hollow body which must withstand even a constant and constantly changing flexural loading. In addition to ensuring appropriate stability however the rotor blade must be of an aerodynamic shape and as far as possible is to appropriately retain that shape. All those demands are so special that they require specific consideration dedicated thereto. In particular it is possible to have recourse to previous experience in steel constructions only to a severely limited extent.
[0007] For wind power installations, the ‘Smith-Putnam Wind Turbine’ is known from the 1940s, which used a steel rotor blade. Information about that ‘Smith-Putnam Wind Turbine’ is to be found on the English Wikipedia page (http://en.wikipedia.org/wiki/Smith-Putnam_wind_turbine). A rotor blade used there can also be found from the Internet, namely the Internet page http://www.situstudio.com/blog/2010/09/01/smith-putnam/.
[0008] As can be seen from the foregoing Internet blog the rotor blade of the Smith-Putnam Wind Turbine has been constructed with a rotor blade profile that is constant over the entire axis thereof. That naturally leads to simplifications in terms of production engineering in comparison with today's modern rotor blades which are of an axially continuously varying profile. In that respect the profile changes in the axial direction in size and also in its nature. In addition a rotor blade of a modern wind power installation of today is also twisted in the axial direction to take account of the different afflux flow directions which occur, due to the rotation of the rotor, at different spacings from the rotor hub. Added to that is the fact that particularly large rotor blades and in particular rotor blades of very great depth in the region near the hub must be of a multi-part structure for transport purposes.
[0009] The complexity of a modern rotor blade is therefore not to be compared to the rotor blade known from the Smith-Putnam Wind Turbine. Manufacturing a modern rotor blade or a portion of a modern rotor blade from steel thus requires a large number of individual considerations, approaches and solutions.
[0010] As general state of the art attention is to be directed to the documents DE 1 433 768 A, DE 1 180 709 A, DD 159 055 A1, DE 24 02 190A and WO 2010/100066 A2.
BRIEF SUMMARY
[0011] Therefore the object of the present invention is to address at least one of the aforementioned problems. In particular the invention seeks to provide that rotor blade production of a rotor blade or a part thereof from steel is improved or first made possible at all. At least the invention seeks to propose an alternative solution.
[0012] According to one embodiment of the invention there is proposed a process according to claim 1 . In accordance therewith hot forming of a steel sheet of a wind power installation rotor blade to be produced is effected in such a way that firstly the steel sheet to be shaped is heated in a furnace. In this case the steel sheet firstly in the form of a flat even plate is disposed on a furnace bogie.
[0013] After the heating operation the heated steel sheet is moved with the hearth bogie from the furnace into a pressing apparatus for the hot forming operation. The hearth bogie thus travels directly with the steel sheet from the furnace into the pressing apparatus without transloading being effected therebetween. Transloading is then effected in the pressing apparatus, in which case the heated steel sheet is transloaded from the hearth bogie on to a form bogie having a counterpart form. The counterpart form can also be referred to as the form bed. The heated steel sheet is now disposed on the counterpart form and can be pressed. Pressing is effected by a pressing punch or die which is pressed on to the steel sheet in such a way that the steel sheet is formed between the pressing punch and the counterpart form. In particular in that case the steel sheet assumes the shape of the pressing punch and the counterpart form which are matched to each other.
[0014] Preferably the operation of transloading the steel sheet is effected in such a way that the steel sheet is lifted off the hearth bogie in the pressing apparatus. The hearth bogie is now separated from the steel sheet and can be moved out therebeneath. Accordingly the space beneath the steel sheet becomes free and the counterpart form is moved with the form bogie into the pressing apparatus under the lifted steel sheet. The steel sheet can now be lowered on to the form bogie and thus on to the counterpart form. As a result any apparatus for performing the lifting operation does not need to be provided in the form of an external apparatus like a fork lift truck. Rather such a lifting means can be stationary. Preferably that lifting apparatus forms a part of the pressing apparatus or is fixedly connected thereto. The transloading operation is thus effected by lifting the steel sheet and changing the two bogies.
[0015] Preferably the hearth bogie moves on a rail system from the furnace to the pressing apparatus. It is also desirable for the form bogie to travel into the pressing apparatus on a or the rail system. That makes it possible to achieve a simplification in the operating movements, in particular conveying the heated steel sheet from the furnace into the pressing apparatus and on to the counterpart form. Preferably the hearth bogie and the form bogie use the same rail system and in particular the same pair of rails. That makes it possible to achieve an efficient apparatus which also makes the change of the steel sheet from the hearth bogie to the form bogie correspondingly efficient and practical.
[0016] According to one embodiment of the invention there is proposed a forming apparatus for the hot forming of a steel sheet according to claim 4 . That forming apparatus includes a furnace for heating the steel sheet, a pressing apparatus for forming the steel sheet and a hearth bogie for transporting the steel sheet from the furnace to the pressing apparatus. In that respect that forming apparatus is particularly adapted to carry out a process as described hereinbefore for hot forming of a steel sheet.
[0017] Preferably the furnace has a furnace bottom with a bottom opening and the hearth bogie is characterized by a chassis for moving from the furnace to the pressing apparatus, a carrier table for carrying the steel sheet when being heated in the furnace and when being transported from the furnace to the pressing apparatus, and a carrier structure for connecting the carrier table to the chassis. In that case the carrier structure is so designed that it extends from the chassis through the bottom opening of the furnace to the carrier table in the furnace when the carrier table is carrying the steel sheet in the furnace. In other words the hearth bogie can move with its chassis under the furnace bottom but in that case can hold the carrier table in the furnace by means of the carrier structure.
[0018] Preferably the forming apparatus in that case is so designed that the hearth bogie can move into the bottom opening or out of same with the carrier structure when the furnace is opened. In particular the bottom opening is in the form of an approximately slot-shaped opening in the furnace bottom and the carrier structure is of a correspondingly slender configuration so that it can move into that slot-shaped opening when the chassis travels under the furnace. After heating of the steel sheet it can thus be easily transported from the furnace to the pressing apparatus. For that purpose it is only necessary for the furnace to be opened and the hearth bogie can travel across to the pressing apparatus.
[0019] Preferably the forming apparatus has a displaceable form bogie for receiving the steel sheet in the pressing apparatus, the form bogie providing a counterpart form or form bed in the forming operation.
[0020] Preferably there is provided a rail system for displacement of the hearth bogie from the furnace to the pressing apparatus and for displacement of the form bogie into the pressing apparatus and correspondingly also out of same. In particular there is provided a pair of rails provided from one side of the pressing apparatus through the pressing apparatus and beyond to the furnace. Preferably the spacing between the furnace and the pressing apparatus is kept short. The spacing can be kept of such a size that there the empty hearth bogie, after the heated steel sheet has been transferred on to the form bogie, can be equipped with a fresh cold steel sheet.
[0021] Preferably the lifting apparatus which lifts the heated steel sheet for the transloading operation forms a part of the pressing apparatus or is arranged on the pressing apparatus and is preferably operated thereby. In that case the lifting apparatus is in particular so designed that it ensures uniform lifting of the steel sheet from the hearth bogie and equally ensures that the heated steel sheet is uniformly deposited on the form bogie.
[0022] Preferably the lifting apparatus has a plurality of lifting arms which are respectively provided with a motion mechanism and which are adapted to laterally engage under the steel sheet. It is proposed in that respect that the lifting arms are so actuated and in particular a corresponding control is provided that they lift the heated steel sheet uniformly, in spite of their own motion mechanisms.
[0023] As a result the weight is distributed uniformly to the lifting arms and in addition this counteracts the risk that the heated steel sheet could suffer flexural deflection.
[0024] The pressing apparatus is intended in particular to push or press basically from above on to the heated steel sheet with a form, while the heated steel sheet rests on a counterpart form or form bed corresponding thereto. Nonetheless it is preferably proposed that a plurality of individual presses are provided for that purpose, in particular eight individual presses are proposed. The necessary force which has to be applied can be distributed to those individual presses. By means of a suitable control system nonetheless the force applied by that plurality of individual presses, in particular therefore eight such presses, is uniformly produced so that the form used for the pressing operation can be pressed down with the total force of the individual presses. The individual presses thus together form a forming die or punch for forming the steel sheet. Preferably the individual presses have their own drive units which for example can be actuated hydraulically or in some other fashion such as for example by means of a toggle lever mechanism.
[0025] In addition there is proposed a hearth bogie having at least one of the above-described features or properties.
[0026] In the described forming process for the hot forming of a steel sheet it is possible to use steel parts of basically usual structural steel, which are heated in the furnace to their respective forming temperature in order to achieve normalization of the material such as for example steel or aluminum. With one kind of steel the forming temperature is for example 900 to 930° C. The temperature should be observed as accurately as possible in order not to damage the structure of the steel. The steel part, namely the steel sheet, can be a steel sheet which is up to 3×12 m in size and which after the heating operation is moved out of the furnace with the hearth bogie to the forming station, namely the pressing apparatus. In that forming station or pressing apparatus the steel sheet is transferred on to the form bogie with the counterpart form which can also be referred to as the form bed. Thus here the heated steel sheet is lifted by means of a plurality of lifting arms and the hearth bogie is replaced by the form bed. For that purpose both, namely the hearth bogie and the form bogie carrying the form bed, are preferably mounted on the same rails.
[0027] The lifting arms are so designed that the steel part is lifted in a direction which is as perpendicular as possible, in which case the steel part, namely the steel sheet, is lying approximately horizontally.
[0028] Thus the hearth bogie moves directly into the furnace and from the furnace to the forming station. Hitherto it was known from the state of the art for a steel part to be moved out of the furnace with a bogie which basically formed the complete underside of the furnace, and then to be transferred from there with a fork lift truck. In a preferred solution however it is proposed here that only a narrow aperture in the furnace bottom is used, which is narrower than the width of the steel sheet to be heated.
[0029] A preferred pressing apparatus or press can be designed for 640 tons pressing pressure and can be formed by a plurality of and in particular eight individual presses which operate uniformly to apply the necessary total pressure. The specified pressing pressure is a possible example and for example can also be higher or lower, depending on the kind of material and the sheet size.
[0030] According to one embodiment of the invention there is also proposed a welding process according to claim 13 . Such a welding process is proposed for joining formed steel sheets and in particular steel sheets shaped as described above to afford a rotor blade or a rotor blade segment. For that purpose the steel sheets to be joined are arranged in relation to each other in a preparation arrangement and fixed. That preparation arrangement therefore already basically represents the rotor blade segment to be produced, in which respect fixing can be provided only to such an extent that the welding operation for definitively and fixedly joining the rotor blade can be effected without the formed steel sheets falling apart in that case. That preparation arrangement thus essentially forms a fixed pack. In that preparation arrangement the steel sheets are then joined together by welding at respective contact edges forming a weld gap. The welding operation is effected in that case in the form of submerged arc welding by a welding robot.
[0031] Submerged arc welding is basically known in the form of a fully automatic welding process for long straight horizontal weld seams such as for example a longitudinal tube seam. According to one embodiment of the invention it is now proposed that the submerged arc welding process by means of a welding robot be used for the complex forms and thus complex weld seams of a rotor blade segment. In that respect it is to be noted that such a rotor blade segment can be made for example from 24 formed steel sheets. In that respect for example firstly two partial segments can be manufactured each from 12 formed steel sheets. In that case all or at least most of the steel sheets used here are different and accordingly that also involves a large number of different weld seams. Hitherto no submerged arc welding process is proposed in the state of the art for that purpose.
[0032] A problem with submerged arc welding is that the powder also covers the respective weld position in order thereby to provide a suitably screened welding condition. Basically the powder is held in its place by the force of gravity. In a preferred embodiment it is now proposed that the preparation arrangement is moved in the welding operation by a movement apparatus, more specifically in such a way that the welding operation is respectively effected on an upwardly facing region of the weld joint. In that case for example the weld joint is a notch or a notch-shaped groove which is produced by two milled edges of two steel sheets to be joined being placed together. That weld joint should be upward as much as possible so that the powder can lie thereon in the welding operation. That can also embrace the situation where the weld joint is in the interior of the preparation arrangement, that is to say basically in the interior of the rotor blade segment to be produced. More specifically the rotor blade segment to be produced is basically a hollow body which for example has an outer skin substantially corresponding to the surface of the rotor blade segment in that region. The steel sheets to be fitted together thus substantially form the outer layer of the rotor blade segment to be produced. Reinforcing struts in the interior of that rotor blade or rotor blade segment can be added and also need welding.
[0033] Now for the welding procedure the welding robot which for example can have a robot arm with six joints is moved along the respective weld joint to be welded. In that case the preparation arrangement is moved in such a way, in particular being rotated about a substantially horizontal axis, that the welding robot is admittedly moved in tracking relationship along the weld joint, but finds a respective approximately horizontal portion for the welding operation. Preferably therefore tracking guidance is effected in duplicate fashion, namely a movement, in particular rotation, of the preparation arrangement and therewith the steel sheets in such a way that the weld seam is approximately horizontal, the welding robot performing the remaining tracking guidance along the weld joint.
[0034] Preferably the preparation arrangement is thus rotated during the welding operation, this being effected in particular at varying speed. The rotor blade segment is of a rather elongated hollow profile in cross-section, with respect to a rotor blade longitudinal axis. By virtue of rotation at a varying speed, it is possible to take account of that fact. In particular the rotor blade is rotated slowly or at times not at all when a correspondingly long profile portion is upward or downward so that the welding robot has sufficient time to weld along a corresponding horizontal weld seam. Accordingly the rotary movement is performed more quickly when only a short portion such as for example a rotor blade leading edge is facing straight down or up in the rotary movement, and is welded.
[0035] Preferably the rotary speed can be varied with knowledge of the respective profile portion to be welded, in dependence on a corresponding angular position in respect of such rotation.
[0036] Preferably the contact edges of two respective formed steel sheets are provided in that case with a bevel so that together they are of a notch or wedge shape. That wedge or notch shape promotes the welding operation insofar as at least one weld seam can be produced in the submerged arc welding process in that notch-shaped groove. It is to be noted that a clean tidy weld is important and it is pointed out that usually a number of weld seams are to be implemented in that one weld joint.
[0037] According to one embodiment of the invention there is also proposed a welding apparatus for joining formed steel sheets to provide a rotor blade or rotor blade segments according to claim 18 . That welding apparatus has at least one welding robot for joining the steel sheets which are adjacent in the preparation arrangement by a submerged arc welding process. There is also provided a motion apparatus for moving the preparation arrangement so that the welding operation can be carried out in each case on an upwardly facing region of the weld joint. That welding apparatus is adapted in particular to performing the above-described welding process in accordance with at least one of the specified embodiments.
[0038] Preferably there is provided a hand control means with which a welder can switch over to manual operation on site and can assist or further guide the robot with the hand control means in the welding operation. In principle manual submerged arc welding is problematical because the welder cannot see the weld seam and thus the welding result or the welding procedure because of the powder. Nonetheless such manual intervention can be appropriate, particularly when the welding robot comes away from the seam or threatens to do so. That can be the case for example when the welding robot is entirely or partially oriented to a pre-programmed configuration of the seam, but the seam deviates from the pre-programmed configuration thereof. Here re-adjustment can now be effected manually by for example the welding robot being moved back on to the weld seam or the center thereof.
[0039] Preferably in this case a rotor blade segment to be manufactured is welded together from 24 steel formed parts, that is to say steel sheets which have already been formed. The steel formed parts, that is to say steel sheets, are for that purpose put into position and welded. For the welding operation, a bevel is provided when cutting the steel sheets to size so that the bevels of two steel formed parts which are fitted together form a notch or similar gap. That notch is welded with an SAW process, namely the above-mentioned submerged arc welding process, with a plurality of layers and by means of a welding robot. Usually robots do not weld in an SAW process but they do that only in respect of one layer because after the step of welding each layer the powder has to be removed, which requires manual operation.
[0040] Preferably the welding robot is adapted partially for manual operation insofar as it can weld automatically, but in that case a welder observes the operation of the welding robot and can possibly intervene. A suitable control stick which is colloquially also known as a joystick can be provided for that purpose. A good welder can hear the quality of the weld seam and the intervention can be meaningful as a result, in most cases however manual intervention will be restricted to the welder performing a correcting intervention if the part actually to be welded deviates from the basic part, in particular deviating slightly.
[0041] The SAW process presupposes that the respective seam to be welded is downward so that the powder does not slip away. For that purpose in an embodiment it is proposed that the rotor blade is to be rotated in such a way that the location which is just to be welded is respectively downward. If a peripherally extending seam is being welded the rotor blade segment is to be continuously rotated. In that respect it is to be borne in mind that the rotor blade segment is not circular and the rotary speed is preferably matched thereto. Preferably the motion apparatus and in particular the rotating apparatus for rotating the rotor blade segment has three axes of rotation. The welding robot preferably has six joints to have corresponding degrees of freedom.
[0042] According to one embodiment of the invention there is also proposed a cutting process for cutting formed steel sheets of a wind power installation rotor blade to be produced to size by means of a plasma robot in accordance with claim 21 . The term plasma robot is used here to denote a laser robot which cuts the steel sheet by means of a laser beam.
[0043] It is proposed that the cutting process firstly takes place in such a way that the workpiece is put on to a form table, namely being fixedly clamped thereon. The table is fixedly connected to the plasma robot so that there is a fixed known link to the robot axes. A processing head of the plasma robot is then guided on the workpiece along a three-dimensionally extending provided cutting line in order to measure the workpiece in that region and to detect any deviations between the workpiece and the underlying original part and to establish the cutting line for the specific workpiece, the cutting line also being referred to hereinafter as the guide cutting line. In that case in particular the spacing from the processing head to the workpiece is detected and the processing head is guided along the surface of the workpiece at a spacing relative thereto, that is as constant as possible. To measure the spacing, a small plasma current already flows, which provides that a marking line which can also be referred to as the marking seam is produced at the intended cutting line that is adapted to the workpiece. In the measurement operation the plasma robot records the altered cutting line, which more specifically has been adapted to the workpiece, which is thus deposited as the guide cutting line and corresponds to the marking seam. For the sake of simplicity features of the measurement procedure can also be explained in connection with placement of the marking seam although placement of the marking seam or at any event the result of the placed marking seam is not unconditionally important.
[0044] In the steps of positioning and/or clamping the workpiece on the form table, a base plane is established, which should represent for example a central plane for the specific workpiece. That base plane can be selected differently for different workpieces. It is preferably adopted for workpieces of the same structure and is thus selected in identical fashion. In the measuring operation and preferably also in the cutting operation, two directions of movement are important, which are referred to hereinafter as the stamping direction and the piercing direction, or in simplified form as stamping and piercing. Movements which are performed perpendicularly to said base plane are referred to as stamping. Movements which take place in the working direction, that is to say in the direction in which a cutting laser of the plasma robot also faces, are referred to as piercing. Those directions, stamping and piercing, can thus be identical, namely where the laser is perpendicular to the base plane. The laser is for example perpendicular to the base plane where the current processing position of the workpiece is in plane-parallel relationship with the base plane.
[0045] While the processing head is guided along the intended cutting line deviations in respect of the workpiece, in particular in relation to the stored original part, in respect of height, are to be expected, namely in the stamping direction, that is to say perpendicularly to the base plane. Such a deviation nonetheless make itself noticeable to the plasma robot as a deviation in the piercing and stamping direction as long as the two directions do not coincide. Accordingly tracking guidance of the processing head of the plasma robot can thus also be effected at an approximately constant spacing in the stamping and/or piercing direction.
[0046] Preferably a correction value which has a component in the stamping direction and a component in the piercing direction is determined from those deviations for trackingly guiding the processing head. Particularly preferably a mean correction value which takes account of both deviation components is formed from both deviation components. If ‘a1’ is the deviation in the stamping direction and ‘a2’ is the deviation in the piercing direction a correction value ‘k1’ in the stamping direction and a correction value ‘k2’ in the piercing direction can be calculated as follows:
[0000] k 1=0.5 *αa 1 ; k 2=0.5 *a 2
[0047] The resulting correction is afforded by vectorial addition of the two correction components. In the above calculation a1 and a2 are respectively 50% involved. Alternatively it is possible to implement a weighting g1 and g2 for a1 and a2 respectively. That then gives the following relationships:
[0000] k 1 =g 1 *a 1 ; k 2 =g 2* a 2
[0048] For g1=g2=0.5 both calculation rules are identical. Ideally the total of g1 and g2 is equal to 1. To take account of minor non-linearities it may be appropriate for that total to differ from 1 by a few percent, in particular to be greater than 1 by 1 to 5% if the processing head measures the workpiece from the concave side or 1 to 5% smaller if the processing head measures the workpiece from a convex side. Preferably measurement is made from the concave side.
[0049] From practical points of view therefore it must be assumed that the obtained formed steel sheet to be cut, namely the workpiece, is not exactly of the ideally assumed form, namely that of the original part, and in addition also varies from a steel sheet which is formed as the closest being theoretically identical. Thus the marking seam which reproduces the measured seam is in reality not identical to the cutting line because the formed steel sheet part usually is not of the idealized form.
[0050] It is then proposed that the steel sheet is cut by means of a processing head of the plasma robot by the processing head being controlled in accordance with the guide cutting line established in the measuring operation. The marking seam reproduces that established guide cutting line. In that case guidance along the marking seam is preferably effected based on the values recorded in measurement of the specific workpiece so that the possibly visible marking line is at any event not required by the robot. In that respect it is to be emphasized once again that a large number of different steel sheets have to be assembled to produce the rotor blade segment, and those sheets have to be previously cut to size and shape after they have been formed. Those formed steel sheet parts require a cutting line and thus ultimately a cutting edge which is in practice not constant in any of the three Cartesian directions. Thus a three-dimensionally extending cutting line or three-dimensionally extending marking seam is used to mean such a line or seam which is not in a plane. Thus here there is a substantially more complex shape for the line or seam, than would be the case for example when cutting a tube. When such a tube is cut, in particular transversely relative to the longitudinal direction, the result is a circular cutting edge. Naturally that tube which is taken by way of example is three-dimensional and the circular cutting edge also extends basically in space, but there is a plane in which that circular cutting edge, given by way of example, is disposed, namely usually a plane in relation to which the longitudinal axis of the tube forms the normal line. And if in that respect such a circular cutting edge can be completely considered as a two-dimensional cutting edge, only the plane is correspondingly involved.
[0051] That is not the case with the complex formed steel sheets as are the basis of the present invention, at least for some cutting edges. The present cutting process is thus based on a three-dimensional control, namely tracking guidance of the processing head in three Cartesian directions.
[0052] Preferably the proposed cutting process also performs the operation of cutting a bevel as preparation for a notched or wedge-shaped weld joint, as was described hereinbefore in connection with the welding process. In that way it is already possible to prepare in the cutting operation for the intended submerged arc welding procedure which is proposed here by means of a plurality of layers, namely a plurality of weld seams per weld join.
[0053] In addition there is proposed a plasma robot for cutting formed steel sheets to size for a rotor blade to be produced of a wind power installation, in accordance with claim 25 . That plasma robot includes a processing head with a laser beam generator for delivering a laser for cutting the steel sheet. In addition there is a motion mechanism, in particular a multi-joint robot arm, for moving and trackingly guiding the processing head. In addition there is a sensor for detecting a marking seam and/or for detecting the surface of the steel sheet. In particular the plasma robot is adapted to perform a cutting process as described hereinbefore at least in accordance with one of the stated embodiments.
[0054] Thus at least in accordance with an embodiment for cutting the shaped or formed steel sheets to size there is proposed a plasma robot, that is to say a laser robot. Such a process provides firstly effecting measurement of the formed steel sheets along a desired cutting line, namely the so-called original cutting line, and in so doing establishing a specific cutting line, namely a so-called guide cutting line, wherein a marking seam corresponding to the guide cutting line can be implemented. In this case therefore deviations from the ideal form of the steel sheets are taken into consideration. In measuring, establishing the guide cutting line and placing the marking seam the robot is adapted to the specific contour which in that respect it basically follows. In that case, by way of the plasma beam, it acquires items of information about the spacing relative to the steel sheet, that is to say relative to the wall of the steel part, and can thus track its respectively current position. The precise trajectory of movement which corresponds to the guide cutting line is in that case recorded and stored in the control system. The robot then orients itself to that trajectory in the subsequent cutting operation. As a particularity here attention is to be once again directed to the fact that the object to be cut, namely the shaped or formed steel sheet, is a three-dimensional object in the sense that the surface changes in three Cartesian directions. That results in the above-mentioned problem that upon deviations in the surface from the ideal form, a decision is to be taken as to the direction in which the laser beam is to be adjusted. If therefore a piercing operation is to be effected, namely in the direction of the laser beam, or a stamping operation, namely transversely to the base plane. It is proposed here that a combination or a compromise of both directions is to be involved.
[0055] Moreover in the cutting operation the cooled steel part, that is to say which has cooled down after the hot forming operation, is held on a suitable support by means of a hydraulic device. The metal sheet is pressed down on that support and deformation in the cutting operation is to be avoided thereby.
[0056] In addition there is proposed a rotor blade of a wind power installation, which includes a steel portion having a plurality of steel sheets, wherein the steel sheets were formed with a forming process according to one embodiment the invention, joined with a welding process according to one embodiment of the invention and/or cut to size with a cutting process according to one embodiment of the invention.
[0057] In addition there is proposed a wind power installation comprising one or more such rotor blades.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0058] The invention is described in greater detail by way of example hereinafter by means of embodiments with reference to the accompanying Figures.
[0059] FIG. 1 shows a perspective view of a wind power installation,
[0060] FIG. 2 shows a perspective view of a forming station,
[0061] FIG. 3 shows a side view of the forming station of FIG. 2 ,
[0062] FIG. 4 shows a front view of a pressing apparatus or a pressing stand,
[0063] FIG. 5 shows a front view of a furnace with a hearth bogie,
[0064] FIG. 6 diagrammatically shows a welding apparatus for submerged arc welding of a rotor blade segment,
[0065] FIG. 7 shows a flow chart for cutting a steel sheet by means of a plasma robot,
[0066] FIG. 8 shows the tracking function of a processing head of a plasma robot, and
[0067] FIG. 9 diagrammatically shows a portion from FIG. 8 .
DETAILED DESCRIPTION
[0068] Hereinafter identical references can be used for similar but non-identical components to emphasize the common aspects of the functionality of some such components.
[0069] FIG. 1 shows a wind power installation 100 comprising a pylon 102 and a pod 104 . Arranged on the pod 104 is a rotor 106 with three rotor blades 108 and a spinner 110 . In operation the rotor 106 is caused to rotate by the wind and thereby drives a generator in the pod 104 .
[0070] FIG. 2 shows a perspective view illustrating the overall configuration of a forming station 200 . Essential components of that forming station 200 are the furnace 202 which here is in the form of an annealing furnace, the pressing apparatus 204 which can also be referred to as the pressing stand, a hearth bogie 206 which transports steel sheets from the furnace 202 to the pressing stand 204 , a form bogie 208 on to which the steel sheet is transferred from the hearth bogie 206 in the pressing apparatus 204 and a rail system 210 connecting the furnace 202 and the pressing stand 204 . The perspective view in FIG. 2 shows an opening 212 of the furnace 202 , through which the hearth bogie 206 can move a steel sheet to be heated into the furnace 202 and out of it again. For that purpose the hearth bogie 206 moves on the rail system 210 which basically includes only one pair of rails, with the carrier table 214 , into the furnace 202 . In that case the steel sheet is carried on the carrier table and is thus conveyed into the furnace 202 . The drawing in FIG. 2 , by way of illustration, does not show such a steel sheet. In this case the rail system 210 is laid below the furnace 202 or below the furnace bottom 216 . An elongate bottom opening 218 is provided in the region of the furnace 202 in the furnace bottom 216 above the rail system 210 .
[0071] As shown in FIG. 3 , the side view of the forming station 200 shows the structure thereof and illustrates inter alia the continuously extending rail system 210 which extends into the structure of the furnace 202 but which is not laid in the furnace 202 as such, but beneath that furnace. Two people 220 are shown by way of illustration in the region of the furnace 202 to demonstrate the size of the arrangement.
[0072] A hearth bogie 206 which has a chassis 222 and a carrier table 224 is supported and guided on the rail system 210 . The carrier table 224 is provided with a multiplicity of support points, on which the steel sheet 226 which is to be heated or which has been heated rests. In that respect the carrier table does not have a table plate, but only that multiplicity of support points. The carrier table 224 is connected to the chassis 222 by way of a suitably connecting carrier structure 228 .
[0073] The rail system 210 extends as far as the pressing apparatus or pressing stand 204 which has eight individual presses 230 which are arranged in two rows along the rail system 210 and of which four individual presses 230 can be seen in FIG. 3 . Those eight individual presses 230 jointly move a forming punch or die 232 .
[0074] Besides the individual presses 230 the Figure also shows lifting arms 234 of which sixteen are provided in the illustrated embodiment, of which eight can be seen in FIG. 3 . The steel sheet 226 is lifted from the hearth bogie 206 by means of those lifting arms 234 when the hearth bogie 206 has arrived in the pressing stand or pressing apparatus. When the steel sheet 226 is lifted by those lifting arms 234 the hearth bogie 206 moves to the position shown in FIG. 3 again and thus out of the pressing stand. The illustrated form bogie 208 then travels into the pressing stand 204 under the steel sheet 226 which has been lifted by means of the lifting arms 234 . The steel sheet 226 can then be lowered on to the form bogie 208 by means of the lifting arms 234 . In that way the steel sheet 226 comes to lie on a counterpart form or block 236 which can also be referred to as the form bed 236 . The heated steel sheet 236 can then be pressed by means of the form or the forming punch 232 , actuated by the eight individual presses 230 , so that the steel sheet 226 can assume the shape of the forming punch 232 and the form bed 236 which is adapted thereto.
[0075] The form bogie 208 is thus shown in FIG. 3 in a waiting position outside the pressing stand 204 . The form bogie has a form bogie chassis 238 which has a very high level of stability and which is capable of carrying high forces as it not only has to carry the steel sheet 226 but also the weight of the form bed 236 .
[0076] FIG. 4 shows a front view of the pressing stand 208 and in that respect shows a front view of the forming punch 232 on the form bogie 208 , and also shows the lifting arms 234 .
[0077] The forming punch 232 is moved by eight individual presses 230 simultaneously and uniformly on to the form bed 236 for forming the steel sheet 226 . The form bogie 208 travels with its form bogie chassis 238 on the rail system 210 and carries the form bed 236 by way of a form carrier 240 . For pressing the steel sheet 226 the form carrier 240 can be deposited on a carrier support 242 arranged on both sides of the form bogie chassis 238 . That can provide that, in the operation of pressing the steel sheet 226 , the enormous pressing forces which occur in that case do not have to be carried by the form bogie chassis 238 . For lifting and lowering the steel sheet 226 the arrangement has the lifting arms 234 which have sheet supports 244 with which the lifting arms 234 can reach under the steel sheet 226 . The selected mechanism for the lifting arm 234 provides for perpendicular lifting of the steel sheet 226 , that is as uniform as possible.
[0078] FIG. 5 shows a diagrammatic front view of the furnace 202 and the hearth bogie 206 . The furnace 202 has a furnace interior 246 and at least one furnace bottom 216 . The hearth bogie 206 is supported with its chassis 222 on the rail system 210 . A carrier structure 228 extends through the elongate bottom opening 218 into the furnace chamber 246 from the chassis 220 . The carrier table 224 is disposed in the furnace chamber 246 and is carried by the carrier structure 228 . Shown on the carrier table 224 is a steel sheet 226 which is heated in the furnace 202 and thus in the furnace chamber 246 .
[0079] The welding apparatus 600 diagrammatically shown in FIG. 6 includes a welding robot 602 and a motion apparatus 604 . A rotor blade segment 606 is fixed in the motion apparatus 604 . The fixing means is not shown in the view in FIG. 6 . In that way the rotor blade segment 606 can be rotated about a longitudinal axis 608 by means of the motion apparatus 604 . The longitudinal axis 608 extends into the plane of the drawing and is illustrated here only as a dot. The motion apparatus 604 for that purpose has a rotary ring 610 which rotates about that longitudinal axis 608 . A drive motor 612 is provided for that purpose, being actuated by a process computer 614 .
[0080] The welding operation is performed by a welding head 616 which forms a processing head and which is arranged on a multi-joint robot arm 618 of the welding robot 602 and is guided thereby. The welding operation is effected in each case at the current weld location 620 on the rotor blade segment 606 . FIG. 6 shows the current weld location 620 in the form of a weld location arranged in the interior of the rotor blade segment 606 . It is equally possible to produce an outwardly disposed weld seam which in each case is disposed appropriately at the top on the rotor blade 606 .
[0081] By rotation of the rotary ring 610 and thus rotation of the rotor blade segment 606 about the longitudinal axis 608 the motion apparatus 604 provides that the current weld location 620 is always arranged on a horizontal portion of the rotor blade segment 606 . In the situation of the illustrated internal welding this means that the rotational apparatus 604 provides that the current weld location 620 is always disposed substantially downwardly. In the case of external welding this basically means that the current weld location 620 is substantially always disposed upwardly.
[0082] In this respect the precise position of the current weld location 620 alters in two directions perpendicular to the longitudinal axis 608 and illustrated in
[0083] FIG. 6 as the x- and y-directions. Depending on the respective configuration of the seam to be welded, there can also be a movement in the direction of the longitudinal axis 608 . For the sake of completeness it is pointed out that the illustrated rotor blade segment 606 which prior to the welding operation can also be referred to as the preparation arrangement 606 substantially represents a hollow body serving as a basis for a rotor blade or part of a rotor blade. A specific aerodynamic shape therefore does not yet have to be provided at this stage in the operation of welding the hollow body. In particular elements such as for example a trailing edge profile which converges to a point can be added later.
[0084] To take account of the change in position of the current weld location 620 the welding robot 602 guides the welding head 616 in tracking relationship with the respectively current weld location 620 by means of the robot arm 610 shown for illustration purposes. It is pointed out that the arrangement of the welding robot 602 in FIG. 6 is only by way of illustration. In particular the robot arm 618 will not extend through the rotary ring 610 and also not through a skin of the rotor blade segment 606 . Rather, the robot arm 618 is guided in the longitudinal direction approximately along the axis of rotation 610 through the rotary ring 610 and into the rotor blade segment 606 . Such a robot arm can be of a length of over 20 m and in particular a length of up to 35 m.
[0085] In addition provided on the welding robot 602 is a hand control means 622 , by means of which a person 624 can also manually intervene in the welding control.
[0086] FIG. 7 shows a simplified flow chart for the operation of cutting a formed steel sheet by means of a plasma robot, that is to say by means of a robot which cuts the formed steel sheet by a laser. The flow chart 700 begins in the positioning block 702 , where the shaped steel sheet is fixed in a predetermined position and thus positioned.
[0087] Then, as indicated by data block 704 , the procedure involves a selection of the data in which the data are stored in particular for the steel sheet which is currently to be cut, for the corresponding cutting line, in particular for an intended original cutting line. The data block 704 is logically arranged downstream of the positioning block 702 as it is only establishing the steel sheet to be cut that makes it clear which data set is to be used. For example, different formed steel sheets can be used for producing a rotor blade segment of steel as indicated at 24 . In principle however the time succession of the positioning block 702 and the data block 704 can be in the reverse direction. Simultaneous implementation can also be considered.
[0088] Then, in dependence on the selected data, a desired cutting line, namely the intended original cutting line is travelled as the trajectory in the marking block 706 and in that part of the procedure the steel sheet is measured and a guide cutting line adapted to the steel sheet measured in that way is determined and stored, and a marking seam is set. In that respect the marking seam is the visible result, which gives its name to the marking block 706 . Determining and storing the guide cutting line is important. It is determined while the processing head, namely the welding head, is moved in tracking relationship with the actual configuration of the steel sheet, based on the original cutting line.
[0089] Then in the cutting block 708 which can also be referred to as the cut block 708 the plasma robot or its processing head is again moved over the steel sheet, more specifically based on the previously recorded guide cutting line and thus along the marking seam set in the marking block 706 . In that case tracking displacement of the processing head is effected very precisely and in that respect cutting of the steel sheet is effected along the marking seam.
[0090] The steel sheet is now cut to size and the bevel block Fas 710 can then follow for one, several or all edges of the steel sheet which has now been cut to size, in which block 710 the plasma robot travels with its processing head along the edges in question and bevels same in order thereby to prepare a weld groove in the form of a notch shape when two edges having such a bevel, that is to say correspondingly two steel sheets, are fitted together.
[0091] The cutting operation is thereafter basically concluded and the steel sheet can be removed from its fixing and subjected to further processing. FIG. 8 shows a plasma robot 722 with a processing head 712 . FIG. 8 also diagrammatically shows an actual operation of cutting the steel sheet 714 to size, a solid line having been adopted to illustrate that, while a broken line illustrates an assumed steel sheet 716 which stands for an original steel sheet and thus an original processing part which forms the basis for establishing an original cutting characteristic line which can also be viewed as the optimum cutting characteristic line. In addition FIG. 8 diagrammatically shows a base plane 720 . Basically this diagrammatic view shows the base plane 720 and the two steel sheets 714 and 716 as a side view which however is purely diagrammatic. In particular the two steel sheets 714 , 716 can also be curved into the plane of the drawing, which is not shown here for the sake of simplicity.
[0092] In that respect FIG. 8 shows a snapshot of the processing head 712 when measuring the steel sheet 714 which is actually present, to be processed. The processing head 712 shown in this snapshot illustrates an idealized position in respect of the point PO on the assumed original steel sheet 716 . In the stamping direction R 1 from the point PO there is a spacing a 1 in relation to the actual steel sheet 714 . In addition in the piercing direction R 2 from the point PO there is a spacing a 2 in relation to the actual steel sheet 714 . There is now a large number of possible ways of trackingly guiding the processing head 712 on the basis of the detected deviation in relation to the actual steel sheet 714 . If the processing head 714 is altered by the spacing a 1 in the stamping direction R 1 for correction purposes, that gives the illustrated processing head position 731 .
[0093] If instead the processing head 712 is only altered by the spacing a 2 in the piercing direction R 2 for correction purposes, that results in the second position 732 of the processing head. In accordance with an embodiment however there is proposed a correction which involves a combination of the two corrections, which leads to the first position 731 and the second position 732 respectively. That proposed third position is identified by reference 733 for the processing head. That position takes account both of the deviation al in the stamping direction R 1 and also the deviation a 2 in the piercing direction R 2 . The precise calculation is explained for that purpose in FIG. 9 .
[0094] FIG. 9 firstly shows on an enlarged scale only the two spacings a 1 in the stamping direction and a 2 in the piercing direction. It is proposed here that half the spacing a 1 in the stamping direction be used as the correction vector {right arrow over (k 1 )}. Half the spacing a 2 in the piercing direction is used as the correction vector {right arrow over (k 2 )}. Vectorial addition leads to the overall correction vector 1 7 c . It is possible therewith to determine the new point P N from the optimum point PO. The new point P N is also shown in FIG. 8 and corresponds to the third position 733 of the processing head. That calculation of the correction for the processing head 712 having regard both to the deviation al in the stamping direction R 1 and also the deviation a 2 in the piercing direction R 2 leads to an advantageous result, namely advantageous calculation of the new point P N and therewith the corrected position 733 of the processing head.
[0095] The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent application, foreign patents, foreign patent application and non-patent publications referred to in this specification and/or listed in the Application Data Sheet are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, application and publications to provide yet further embodiments.
[0096] These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure. | The present invention concerns a forming process for hot forming of a steel sheet of a rotor blade to be produced of a wind power installation, including the steps heating the steel sheet in a furnace while the steel sheet is lying on a hearth bogie, displacing the heated steel sheet with the hearth bogie from the furnace into a pressing apparatus for the hot forming operation, transloading the heated steel sheet in the pressing apparatus from the hearth bogie on to a form bogie having a counterpart form and pressing the steel sheet by at least one pressing punch which presses on the steel sheet in such a way that it is formed between the pressing punch and the counterpart form and in particular assumes the shape of the pressing punch and the counterpart form. | 8 |
CROSS REFERENCES TO RELATED APPLICATIONS
Claiming Benefit Under 35 U.S.C. 120
The present application is Division of Ser. No. 08/215,115 Mar. 17, 1994, abandoned which is a continuation of U.S. Ser. No. 07/987,574, filed Dec. 8, 1992, now U.S. Pat. No. 5,313,053, issued May 17, 1994, which is a continuation of U.S. Ser. No. 07/674,756, filed Mar. 25, 1991, now abandoned, which is a continuation-in-part application of U.S. Ser. Nos. 07/660,615, filed Feb. 25, 1991, now U.S. Pat. No. 5,218,187, issued Jun. 8, 1993, 07/467,096, filed Jan. 18, 1990, now U.S. Pat. No. 5,052,020, issued Sep. 24, 1991, and PCT international application PCT/US90/03282, filed Jun. 7, 1990. Said PCT international application entered the national stage under Ser. No. 07/777,393 with a 35 U.S.C. 371 date of Jan. 7, 1992 and with a 35 U.S.C. 102(e) date of Jan. 7, 1992, and issued as U.S. Pat. No. 5,410,141 on Apr. 25, 1995.
The present application is also a continuation-in-part of U.S. Ser. No. 07/965,983, filed Oct. 23, 1992, now abandoned, which is a continuation of U.S. Ser. No. 07/719,731, filed Jun. 24, 1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/441,007, filed Nov. 21, 1989, now abandoned, which is a continuation-in-part of U.S. Ser. No. 06/905,779, filed Sep. 10, 1986, now U.S. Pat. No. 4,882,476, issued Nov. 21, 1989. The disclosures of these applications are incorporated herein by reference.
The present application is also a continuation of U.S. Ser. No. 07/960,520, filed Oct. 13, 1992, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/912,917, filed on Jul. 13, 1992, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/881,096, filed on May 11, 1992, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/820,070, filed Jan. 10, 1992, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/786,802, filed Nov. 5, 1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/777,691, filed Oct. 10, 1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/735,610, filed Jul. 23,1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/719,731, filed Jun. 24, 1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/674,756, filed Mar. 25, 1991, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/660,615, filed Feb. 25 1991, now U.S. Pat. No. 5,218,187, issued Jun. 8, 1993, which is a continuation-in-part of U.S. Ser. No. 07/633,500, filed Dec. 26, 1990, now U.S. Pat. No. 5,202,817, issued Apr. 13, 1993, which is a continuation-in-part of U.S. Ser. No. 07/561,994, filed Jul. 31, 1990, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/558,895, filed Jul. 25, 1990, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/426,135, filed Oct. 24, 1989, now U.S. Pat. No. 5,218,188, issued Jun. 8, 1993, which is a continuation-in-part of U.S. Ser. No. 07/347,849, filed May 3, 1989, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/347,602, filed on May 3, 1989, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/345,200, filed Apr. 28, 1989, now abandoned, which is a continuation-in-part of U.S. Ser. No. 07/305,302, filed Jan. 31, 1989, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates generally to data collection and processing systems using portable, hand-held data terminals for collecting data, and for selectively processing and communicating collected data to other system elements. More particularly, the invention relates to collection apparatus of such hand-held data terminals. Typical collection processes may include reading data and manually keying in such read data. The present invention relates particularly to apparatus for reading data into the terminal. Known automated reading processes are executed by apparatus which includes scanning readers, for example.
In efforts to adapt data collection terminals to a wider scope of uses, terminals with increased ruggedness over state of the art terminals are bringing advances to the art. However, the usefulness of the data collection terminals may also be increased by further reducing the weight and size of the data collection terminals to sizes and weights below the present lower limits of state of the art terminals. Typically a reduction in size might result in the elimination of at least some desirable features. The use of modular data collection terminals would support the reduction in non-essential features to achieve certain reduction in size and weight.
In the data capture field, there are many applications where hand-held data terminals should be of rugged construction so as to survive rough handling. Many operators are not inclined toward painstaking or precise manipulations. An example is in the use of RF data capture terminals on forklift trucks in factories and warehouses where items to be transported are identified by bar codes. Other examples are found in the fields of route delivery and direct store delivery where many items are handled and the terminal means automates the accounting function. Even in applications where bar code data is transmitted on-line to a central station, it may be desirable for hand-held terminals to be inserted into docking apparatus for the interchange of data signals e.g. the loading of scheduling information or the like into the terminal at the beginning of a working shift. Further where terminal means has memory capacity for accumulating data during a delivery operation or the like, it may be desirable for such data to be transferred to a printer so that a hard copy may be produced. In cases where rechargeable batteries are used, the docking apparatus may provide for the recharging of such batteries at the same time as data communication is taking place.
It is conceived that it would be highly advantageous to provide a data capture system with docking apparatus adaptable to a wide range of terminal means, and which furthermore could be quickly and simply loaded in a relatively foolproof manner, and without requiring attention and care from operators engaged in physically demanding and arduous work routines. A docking apparatus would be desirable that completely avoids the use of mating pin and socket type electrical connections, and that does not rely on a specialized configuration of the terminal, e.g. the provision of an optical scanner tip which may be used for data communication. However, pin and socket type connectors may be utilized.
In connection with the use of portable data systems it is conceived that it would be highly advantageous to be able to readily upgrade a basic hand-held terminal to incorporate bar code scan type readers and various image readers as they are progressively improved and developed. A particular goal would be the implementation of the auxiliary image reader function in a rugged configuration free of moving parts. However, in the case of autofocus readers, the current state of the art may require dynamic components for the sake of optimum compactness and economy.
SUMMARY OF THE INVENTION
A laser scanner may be added to a data collection terminal unit which typically features a radio frequency transceiver module.
In accordance with particular features of the invention, a radio transceiver and a laser scanner are integrated into a single module with only a minimal increase in volume over the volume of a radio transceiver module without the laser scanner unit.
According to another aspect of the invention, rotatively mounted scanning mirrors of a laser scanner are formed about magnetic poles of an armature of a motor for rotating the mirrors.
In accordance with another feature of the invention, electronic elements and physical elements for implementing functions of a laser scanner of the hand-held data collection terminal and electronic coupling circuits for interconnecting the laser scanner with the data collection terminal are disposed in interleaved relationship with electronic components for processing communications between a transceiver and the laser scanner.
Various other features and advantages of the data terminal in accordance with the invention will become apparent from the following detailed description, which may be best understood when read with reference to the appended drawings.
Accordingly, it is an important object of the present invention to provide a portable data system wherein technologically advanced image reader devices can be readily accommodated.
In a presently preferred configuration particularly suited for forklift truck applications and the like, a portable data terminal with a rugged surface contact configuration accommodates supply of power by the vehicle when the terminal is placed in a vehicle mount; further, the terminal batteries may receive charge while the terminal is operating from the vehicle power so that full battery capacity is available when portable operation is required. However, other contact means might also be utilized.
In accordance with a further development of the invention, portable terminals, for example, may be quickly removed from the charging system by grasping of the terminal itself followed by a simple lifting extraction.
In accordance with an important aspect of the present invention, a docking apparatus removably receives portable data terminal and code reader means for purposes of data communication, e.g., with a host computer and/or for the recharging of rechargeable batteries. In one potential embodiment the terminal and reader means may have electrical contact pad means generally flush on their exterior. In such an embodiment, an abutting type engagement between the contact pad means and cooperating electrical contact means of the docking apparatus may be used for transmitting charging current such that the typical pin and socket type docking connections are entirely avoided.
In accordance with another aspect of the invention the same basic docking structure may be provided with greater or lesser numbers of contact positions. For example, one type of hand-held terminal intended for on-line RF communication with a host computer may have six contact pads for coupling with a local area network, and may have a nine position electrical connector for compatibility with an earlier type of interface system requiring interfitting of pin and socket connectors; another type of hand-held terminal designed for route accounting applications may have, e.g., twelve external contact pads and be intended for interfacing only with systems having provision for open abutment type interconnection.
The terminal and/or reader receptacle means is preferably arranged so that with the terminal or reader secured therein, each line of the display remains visually observable in a convenient orientation relative to a driver of a vehicle. Also all of the key positions of the keyboard are manually accessible, the legends on the keyboard having an orientation so as to be conveniently readable, e.g. by the driver of the vehicle. In particular the axis of each line of the display and of each row of key positions should be generally horizontal (rather than vertical) and the alphanumeric characters of the display and keyboard legends should be upright (rather than inverted) as viewed by the operator.
Also most preferably the terminal or reader can be inserted into the receptacle with one hand and is securely retained. Ideally the terminal or reader is automatically secured with a snap type action which is perceptible, e.g., audibly and tactually to the operator.
In some instances a resilient bias may serve to firmly position the terminal or reader for steady reliable electrical contact at each abutting type contact position in spite of vehicle jarring and vibration or the like. For enhanced security of retention with the docking apparatus, e.g. in mobile applications, the terminal or reader may be automatically affirmatively retained in its receptacle e.g. by means of a detent type action.
One exemplary embodiment of data capture terminal unit is provided with a plurality of electrically conductive pads generally coplanar with the external surface of the housing. Such electrically conductive pads may be interconnected by internal circuitry to the connector elements of a D-style connector mounted upon the housing end cap such that recharge power and data communication pathways may be made through either or both of the connector means. The electrically conductive pads are positioned such that they may be engaged with mating elements having sufficient resilience to maintain stable electrical contact therebetween while the terminal is in a docking receptacle or the like.
According to another aspect of the invention, a laser light source may provide simultaneous illumination of a complete image line or a complete image column, or a substantial linear segment thereof, facilitating the achievement of a rugged image reader unit preferably without moving parts in the illumination system. In a further development a long range CCD image reader having auto-focus capabilities may be utilized with a fan beam for simultaneously illuminating a complete image line over a substantial range of distances.
Various other features and advantages of the data terminal in accordance with the invention will become apparent from the following detailed description, which may be best understood when read with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic illustration of a laser bar code reader system in accordance with the present invention;
FIG. 2 is a graphical illustration for explaining one embodiment of filter means for use in FIG. 1;
FIG. 3 illustrates another embodiment of filter means for use in FIG. 1;
FIG. 4 is a diagrammatic end elevational view of a laser bar code scanner unit wherein the laser beam is to be swept over an extended scanning path to read a relatively wide bar code label;
FIG. 5 is a somewhat diagrammatic view taken generally along the line V-V of FIG. 4;
FIG. 6 is a diagrammatic view taken generally along the line VI-VI in FIG. 4 and indicating exemplary electronic circuitry for association with the swept laser beam scanner embodiment of FIGS. 4, 5 and 6;
FIG. 7 illustrates a wand type bar code scanner in accordance with the present invention;
FIG. 8 is a longitudinal sectional view taken from the second figure of U.S. Pat. No. 4,820,911 issued Apr. 11, 1989, and showing a modification thereof so as to practice teachings in accordance with the present invention;
FIG. 9 is a longitudinal sectional view corresponding to FIG. 8, but indicating a duplication of parts as a mirror image with respect to a horizontal plane so that teachings according to the present invention may be applied, and for example, the beam splitter of FIG. 8 omitted;
FIG. 10 shows an exemplary beam pattern at the reference plane for the embodiment of FIG. 9;
FIG. 11 shows a different exemplary beam pattern for FIG. 9;
FIG. 12 shows the relative spectral response of selenium and silicon photo-voltaic materials, and inserts in the plot an exemplary light source output spectrum in the infrared region to which selenium and silicon photocells would be differentially sensitive, e.g. without the use of filters, and in addition to conventional narrow pass filters centered at the laser diode wavelength;
FIG. 13 is a diagrammatic illustration of a stacked bar code which may be read by the illustrated embodiments;
FIG. 14 is a diagrammatic partial rear elevational view showing a scanner with an external reflected light collector;
FIG. 15 is a somewhat diagrammatic patrial longitudinal sectional view of the scanner of FIG. 8, with a slip-on external photodetector assembly applied to the frontal barrel portion of the scanner housing; and
FIG. 16 is a somewhat diagrammatic horizontal sectional view of the structure of FIG. 15 for illustrating certain details of the external photodetector assembly.
DETAILED DESCRIPTION OF THE INVENTION
Description of FIGS. 1-16
FIG. 1 is intended as a generic illustration wherein scanning of a bar code label Y10 takes place by relative movement between a laser beam indicated at Y11 and the bar code label Y10. For example, the label may be moved in a longitudinal direction as indicated by arrow Y12, or the laser beam may be moved in a scanning direction such as indicated at Y14 for impingement on successive points along a scanning path such as indicated at Y15.
By way of example, a laser light source is indicated at Y20 and respective light detectors Y21 and Y22 are shown for receiving reflected light produced by the beam Y11 at each successive point along the scanning path Y15. By way of example, detectors Y21 and Y22 may be fixedly secured in a housing with the laser source Y20 so as to be focused at a common point such as indicated at Y15a at a suitable distance from an end face of the housing. In one type of embodiment with common point focus, the label Y10 may be moved longitudinally as indicated at Y12 so as to effect sequential scanning of the complete bar code. In another example, the housing itself may be moved in the direction of arrow Y14 so that the complete bar code is sequentially scanned. In a further example, laser light source Y20 and detectors Y21 and Y22 may be pivotally mounted within the housing so as to jointly sweep along the scanning path Y15 so as to scan a complete bar code. In another type of a scanner, the laser light source Y20 is equipped with scanning means for causing the beam Y11 to scan along a scanning path such as indicated at Y15 at a selected distance from the housing, while detectors Y21 and Y22 are arranged to collect reflected light form each successive point along the scanning path Y15. Alternatively, the laser light source Y20 may be simultaneously illuminate the entire region Y15 and the detector means Y21 and Y22 may be pivotally mounted to sequentially scan successive points along the region Y15.
In a specific example in accordance with the present invention, detectors Y21 and Y22 comprise respective light sensors Y31 and Y32 which may be identical, and respective filters Y41 and Y42 which provide generally comparable response to sunlight but provide substantially different responses to the limited spectral band transmitted by the light source Y20, such that an enhanced sensitivity is provided by a differential between the outputs from sensors Y31 and Y32.
In the embodiment of FIG. 2, laser light source Y20 supplies a wavelength of light as indicated at Y50 and the filters Y41 and Y42 have bandpass spectral properties as indicated at Y51 and Y52.
In the embodiment of FIG. 3, the wavelength of the laser light source Y20 is indicated at Y60 and the broadband spectral transmission properties of the respective filters Y41 and Y42 are indicated at Y61 and Y62.
In each of the embodiments of FIGS. 2 and 3, the ordinate axis may represent transmission between zero percent and one hundred percent. In each case, the outputs from detectors Y21 and Y22 are preferably substantially balanced, that is of equal amplitude in the presence of sunlight alone, the differential in a transmission at the wavelength Y50 or Y60, being at least fifty percent in the examples of FIGS. 2 and 3.
In FIG. 4, there is indicated a scanner unit Y70 including a housing with an end face of Y71 which is arranged to confront a bar code label such as indicated at Y10 in FIG. 1 at a selected distance such as three or more inches. In the indicated example of FIG. 4, the laser beam may be scanned along the length of an elongated window indicated at Y73 and may effect scanning in a plane such as indicated at Y74 which would include the scanning path such as indicated at Y15 in FIG. 1.
In the exemplary embodiment of FIG. 4, an array of first and second light detectors is provided with the first detectors such as Y21A and Y21B and the second detectors such as Y22A and Y22B, being arranged in respective pairs such as Y21A, Y22A along the locus of reflected light produced by the scanning of the laser beam. For the example of two pairs as shown in FIG. 4, and for scanning of the laser beam from left to right as viewed in FIG. 4, during scanning of a left segment of the label, reflected light would predominately reach the detectors Y21A and Y22A. In a mid region of the label, reflected light would reach both pairs of detectors with comparable magnitude, and for a right-hand segment of the bar code label, the reflected light would predominately reach the right-hand pair of detectors Y21B, Y22B. For each point along the scanning path the reflected light reaching a first detector such as Y21A of a pair would be of substantially equal magnitude with the reflected light reaching the second detector such as Y22A of such pair.
In the specific example of FIG. 4, a common filter element Y81 having spectral characteristics as indicated at Y51 or Y61 may cover all of the first light sensors such as Y31A and Y31B of the array, while a common filter element Y82 having the spectral transmission properties Y52 or Y62 may be associated with the second light sensors of the array such as indicated at Y32A and Y32B. By way of example, window Y73 and filter elements Y81 and Y82 may form part of the end face Y71 of the housing of the laser bar code reader unit of FIG. 4, other portions of the end face Y71 being opaque, so that light may only enter or exit the housing through window Y73 and filter elements Y81 and Y82.
In FIG. 5, laser light source means Y20-1 is indicated as comprising a laser source Y90 and a suitable scanner system Y91 which may cause a laser beam Y111 of a wavelength such as indicated at Y50 or Y60 to be focused at a point along the scanning path Y15-1 and to scan along the path as indicated by arrow Y112. For beam positions between those indicated at Y114 and Y115, reflected light is predominately received by the pair Y21B, Y22B. For beam positions between Y115 and Y116, comparable amplitudes of reflected light may reach both pairs Y21B, Y22B and Y21A, Y22A, while for beam positions between Y116 and Y117, reflected light may be predominated at the pair of detectors Y21A, Y22A.
In the example of FIG. 5, each detector may have an individual filter element such a filter elements Y42A and Y42B associated with respective second light sensors Y32A and Y32B. In FIG. 5, end face Y71 may provide a common optical window for transmitting the laser beam Y111 at a region such as Y73, FIG. 4, and for admitting reflected light at regions such as indicted at Y81 and Y82 in FIG. 4.
As seen in FIG. 6, each pair of light detectors of the array, such as first and second detectors Y21B and Y22B are symmetrically arranged with respect to the plane Y74 of the scanning laser beam so that the paths for reflected light from each point such as indicated at Y121 along the scanning path Y15-1 to detectors Y21B and Y22B are equal. As in FIG. 5, each detector is shown as comprising a sensor such as Y31B, Y32B, and a filter element such as Y41 B, Y42B with respective spectral transmission properties as indicated in FIG. 2 or FIG. 3.
In each of the embodiments, as indicated in FIG. 6, the output of the detector or each detector pair such as Y21B, Y22B may be supplied to a differential amplifier means such as indicated at Y130A, Y130B. The outputs of the detector pair Y21A, Y22A may be supplied to the differential amplifier means Y130A and Y130B may be suitably combined either on an analog basis or on a digital basis to provide a resultant bar code signal to be decoded. By way of example, a clock Y132 may be connected with component Y131, and with a beam scanner control means Y133 may be constructed and operated so that component Y131 can determine the position of the beam Y111 with reference to the zones Y114-115, Y115-116, and Y116-117, respectively. For example component Y131 may supply pulses derived from clock pulses to component Y133 to drive the scanning operation. Alternatively, beam driving pulses may be generated at component Y133 and supplied also to component Y131.
It is contemplated that the present embodiments will provide a more reliable bar code reading with a given laser source and under natural and supplementary lighting conditions, and further may allow the use of a lower power laser light source, with many attendant benefits such as greater safety, better adaptability to portable (battery powered) and hand-held use, less heat to dissipate, and therefore expected longer life. A differential between the outputs of detectors such as indicated at Y21 and Y22 will provide superior noise rejection properties in comparison to a detector such as Y31 by itself. If necessary, a neutral density filter could be combined with one or the other of the filters such a Y41 and Y42 to balance the detector outputs under broadband illumination (e.g. sunlight).
FIG. 7 shows a hand-held wand type scanner Y100 according to FIG. 2 or FIG. 3 wherein a light emitting diode or other narrow band light source Y120 produces a band of light for example in the infrared region. In this case, wavelength Y50 or Y60 may be of the order of Y910 manometers, and light sensors Y131 and Y132 may be particularly sensitive at this wavelength. According to the example of FIG. 2, filters Y141 and Y142 have passbands as indicated at Y51 and Y52 respectively, while according to the example of FIG. 3, the filters Y141 and Y142 have overlapping wideband characteristics as indicated at Y61 and Y62. In each case, the outputs of the light sensors Y131 and Y132 may be supplied to differential amplifier means such as Y130B, FIG. 6, so as to provide a resultant output especially sensitive to a bar code scanned thereby even in the presence of ambient daylight illumination.
In one embodiment according to FIG. 7, light is transmitted from light source Y120 to a light port Y144 via optical fibers Y145, and reflected light is transmitted via respective optical fibers such as indicated at Y146 and Y147 which terminate at a small-area central region of light port Y144. By way of example, the reflected light transmitting fibers such as Y146 and Y147 may be essentially uniformly distributed at the port Y144 over a central circular area which is small in comparison to the size of a minimum width bar of a bar code to be scanned, so that ambient light has less effect on resolution than where the size of the incident light spot is relied upon to define scanning resolution.
Where lenses are utilized, the reflected light is preferably collected by symmetrically arranged lenses focused at a common reflected light pickup region at the bar code for high resolution scanning of the bar code. (The pickup region may have a small diameter in comparison to a minimum bar dimension.) Preferably in this case also equal amounts of reflected light are transmitted to respective photodetectors such a Y131, Y141 and Y132, Y142. Again it is preferred that the reflected light optics provide the required resolution independently of the size of the incident light spot from the light source such as Y120 so that resolution is less affected by the presence of intense ambient light.
Preferably in each case the response characteristics of the detectors with respect to reflected light are so matched that the first and second light sensors such as Y131 and Y132 provide essentially equal signals when the light source Y120 is not energized and the light port Y144 is held against the bar code, for each incremental position of port Y144 along the length of the bar code, even in the presence of sunlight.
Light source Y120 may be a conventional light source for a wand type scanner such as a light emitting diode, or may be a laser light source.
It will be apparent that many modifications and variations may be effected without departing form the scope of the novel concepts and teachings of the present invention.
a. Description of FIG. 13
FIG. 23 is a diagrammatic view showing a target region for an instant bar code scanner such as a moving beam laser scanner, wherein a visible laser diode of the scanner is pulsed in synchronism with beam deflection to generate one or more visible markers in a marker beam mode.
A laser bar code scanner as shown in FIGS. 1-7 may generate marker spots such as shown at Y13-41, Y13-42. Laser beam scanners conventionally generate a start of scan rectangular waveform as a function of scan motor operation. The start of scan waveform corresponding to X-axis deflection can be used to momentarily turn on a visible laser diode source at the beginning and end of each high rate (X-axis) scan to product marker spots Y13-41 and Y13-42.
In marker beam mode it is preferred that the electronics associated with the photodetector, e.g., as indicated in FIG. 6 be deenergized, e.g., to conserve battery power where the scanner is battery powered. A momentary push button switch (such as indicated at 68 in U.S. pat. No. 4,251,798) or the conventional trigger of pistol shaped visible laser diode scanners may produce a logical signal (e.g. zero volts or ground potential) when actuated, which signals for marker beam mode. In an initial mode before actuation of the manually operated actuator, the scanner may be deenergized. Operation of the manual actuator may establish marker beam mode for as long as the actuator is held in operated condition. In marker beam mode, the scanner mechanism is operated at a suitable rate, e.g. 36 scans per second. For scanning at distances over two feet, the rotary drive could operate at two scans per second to give brighter marker spots. The rotational speed could be slow at the beam turn-on marker intervals, and faster between marker intervals.
Where the scanner is vehicle mounted, or mounted on a manually propelled wheeled device for example, the number of horizontal lines in the scanning raster may be increased, e.g., to 240 or more. Where a complete raster is scanned quickly, or where the scanner may be otherwise held steady during scanning, an area array matrix type photosensor of may be used with a laser beam raster scanner. The laser beam may in such case be of oblong cross section with a Y-axis dimension of, e.g., six mils (0.006 inch) so as to cover a given height of raster with fewer horizontal scan lines. The raster may comprise interlaced fields of horizontal scan lines with the first field beginning with a top horizontal line and the second field beginning with a lowermost horizontal scan line. The brightness of the scanning beam may be controlled during scanning so as to compensate for any lack of uniformity in the sensed intensity of the image over the photosensor area, e.g., due to elapsed time between scanning of different image regions and varying label distance (e.g. due to curvature or the like). A convenient way to modulate light intensity from the laser diode is to supply a high frequency pulse train to energize the laser diode in a frequency range far above the highest information rate, and to vary such high frequency to compensate for nonuniformities (detected, e.g. by intensity sensors such as Y50, Y51, Y52, FIG. 2 located, e.g., to receive reflected light during a first horizontal scan line above the bar code information where the sensors are activated at the marker beam intervals, and then outputs stored digitally and compared).
A scanner such as shown in U.S. Pat. No. 4,251,798 may have a matrix type photosensor and optical system located generally in the filter and photodetector region (58,60, FIG. 2 of U.S. Pat. No. 4,251,798). By using a laser diode source, the housing may be more compact, A
Where the scanner is to operate according to FIGS. 1-7, for example, the intensity of the marker spots such as Y13-41 to Y13-42 may be adjusted in marker beam mode by actuating one of a series of intensity selection keys located on a keyboard (such as 24, sixth figure, U.S. Pat No. 4,251,798 or at Y11A, Y11B, FIGS. 32-33). The intensity selection keys may progressively increase the energizing frequency for the visible laser diode (such as Y20, FIG. 1 hereof, or Y90, FIG. 5 hereof).
When the actuator is released to shift from marker beam mode to symbol reading mode, the same energizing frequency may be used for the visible laser diode as was selected in marker beam mode. Thus, the laser beam will be relatively more intense in symbol reading mode where the distance to the bar code is relatively great and/or where the ambient illumination is relatively intense.
In a preferred symbol reading mode, the scanner does not revert to initial mode automatically when a single bar code line has been successfully read. In one example with a single line bar code scanner, the scanner may be manually displaced to read a stacked bar code. In this example, a beeper or other indicator will indicated a successful reading of a first line of the stacked bar code whereupon the scanner remains in symbol reading mode and the operator may manually tilt the scanner to read further lines of the stacked bar code. If desired upon each successful read, the marker spots, e.g., Y13-41 and Y13-42 for a single line scanner may be flashed after each reading of the same bar code line (e.g. with the photodetector electronics deenergized during such flashing) so as to indicated to the operator that the scanner is reading the same line and ignoring (not storing) the result of such reading. For example, if the scanner mirror has ten facets and is rotated at ten revolutions per second, and if after a successful read of a line the scanner performs nine scans with no new bar code number being read, on the tenth scan the photodetector electronics would be automatically deenergized and the marker spots Y13-41 and Y13-42 flashed. The system would then execute nine further scans with the photodetector system activated. If the further scans revealed a non-bar-code-reading condition consistent with scans occurring between bar code lines, the tenth and further scans could all be with the photodetector active. After, for example, ten consecutive non-bar-code scans, the scanner might accept a bar code reading of the same value as the last reading accepted, (the operator being informed to avoid returning to a previous read label unless such label was to be read and entered a second time).
Where the bar code scanner is progressively tilted to read a series of bar code lines, a beep or other indication will occur each time a new bar code value is registered. After a suitable number of such beeps, e.g. five, the system may be returned to initial condition, e.g. by a rapid manual operation and release of the manual actuator, or the actuator may be operated, e.g. to disable the photodetector electronics and return to marker beam mode to assist in aiming at a new symbol to be read, while conserving in power supplied to the visible laser diode and avoiding unnecessary power consumption by the photodetector electronics.
Where, for example, the scanner is supported by a sliding friction type universal mount while being manually aimed, a key may be actuated to produce only a single, e.g. central marker spot such as Y13-50, FIG. 13. (This is somewhat analogous to the static PSC mode, col. 12 of U.S. Pat No. 4,251,798, except that preferably in the present embodiment the scanner motor is operating at a desired speed, and the visible laser diode is flashed for, e.g., ten percent of each scan interval at the mid region of each start of scan half cycle). While the central marker spot Y13-50 is on the background color of the bar code, e.g. just above the bar code, the marker spot may be adjusted to a suitable intensity by manual selection from a group of marker beam intensity selection keys, or the photodetector may be momentarily switched on by a separate control key to automatically adjust the energizing frequency of the visible laser diode for proper reading operation. For example, a microprocessor used for decoding may have a program for automatically effecting energizing frequency adjustment to provide a suitable photodetector output when the control key is momentarily operated to cause the marker beam to generate a central marker beam spot. The procedure could be carried further by having left and right marker beam spots as well as a central one, the control program determining proper minimum laser diode energizing frequency suitable to the three marker spot locations, or if desired determining a suitable variation of laser diode energizing frequency as a function of beam displacement to maintain essentially uniform illumination of the bar code during a subsequent symbol reading operation. As an alternative, when the actuator is released from marker beam activating position, it may be assumed that the marker spots are aimed at background, and in a first cycle with the visible laser diode energized for a complete scan (or momentarily held in three marker spot mode) the photodetector is turned on and the control program progressively adjusts laser diode energizing frequency until a suitable frequency level or frequency variation pattern is set, whereupon the decoding program is enabled, and the user may progressively scan a series of bar codes with similar background and distance from the scanner.
After completion of scanning of such a group of bar codes and return to initial mode, the adjustment procedure may be automatically repeated each time the actuator is operated to marker beam mode, and then released to symbol decode mode. At each turn off of the scanner, e.g., by quick-actuation-and-release of the actuator, the scanner may be restored to an initial condition such that any new operation of the actuator will result in a selected average energizing frequency for the laser diode energization being reestablished.
b. Summary Description of One Exemplary Embodiment According to FIG. 13
Because of the relatively low power consumed in marker beam mode, it is contemplated that a battery powered scanner may be detachably coupled to a belt-carried sliding friction type universal support, with operation essentially corresponding to that with the universal support mounted on a vehicle, e.g. a forklift truck. In each case a pistol-sharped scanner, e.g., of the single line scanning type can be aimed by manipulation of the scanner handle while observing the corresponding movement of the marker spots. With the marker spots such as Y13-41, and Y13-42 on the symbol background above the symbol, the manual actuator may be released to initiate an automatic adjustment of visible laser diode energizing frequency, the decode microprocessor and photodetector electronics being energized at this time. Once the photodetector is receiving adequate reflected light intensity from each of the marker spots such as Y13-41, and Y13-42, FIG. 13, the scanner automatically switches to symbol decoding mode and the user will see a complete scan line, e.g. Y13-70. Thereupon the user gradually tilts the scanner to successively scan a series of bar code lines, e.g., of a stacked bar code symbol or other two dimensional optically readable information set. As each line (or portion) is successfully decoded, the scanner may emit a single beep. When the user has heard, e.g., five beeps, the actuator may be quickly operated and released to restore the scanner to initial deenergized mode and to reset visible laser diode energizing frequency so that it will be at a desired initial marker beam value when the scanner is again actuated to scanner beam mode. By way of example the initial marker beam frequency may be intermediate the available maximum and minimum values, and may be adjusted by a series of selection keys as previously described. In this way the need for automatic adjustment of laser diode energizing frequency at the beginning of symbol scanning mode is reduced or even eliminated.
Normally in this embodiment, the number of laser diode energizing frequencies need not be large since a major purpose in not using the maximum safe frequency at all times is to conserve battery power. Another objective of adjusting the laser diode energizing frequency would be to avoid saturation effects when reading close-in bar code symbols. Battery power may be coupled to the scanner through the belt mount therefor where the battery pack is supported on the belt, for example. The scanner may contain its own battery pack, e.g. in the handle, where it is to be operated detached from the belt mount in a completely hand-supported mode.
As previously described, in symbol decoding mode, a single beep is sounded for each new bar code value which is read and stored. A given value is stored only once unless there is a selected number of non-bar-code scans (e.g. ten) intervening between the last close-following reading of the given value, and the new reading of such value. The same value is registered again also whenever a different value or values are registered during intervening readings. If the scanner is left in symbol reading mode, provision may be made for returning to initial mode, if a selected number of scans are non-bar-code scans (e.g. result from the scanner being pointed at the floor or some other non-reflective or uniformly reflective target area). The scanner may also return to initial mode if the actuator is not actuated e.g. for twenty seconds regardless of how recently the scanner has registered a valid bar code reading since normally only five or so readings would be made during a given symbol reading operation. Where belt-mounted, the scanner can be automatically reset to initial mode when the belt is opened to remove it from the wearer. On a vehicle, the scanner can be deenergized when the vehicle ignition switch is off. The coupling between a scanner and a universal mount may include an automatic coupling of the scanner to a set of contacts-analogous to automatic couplings as disclosed e.g. in FIG. 11 and FIG. 14, for transmitting charging current, data signals and the like.
c. Description of FIGS. 8-11
As an example, the single line laser bar code scanner of U.S. Pat. No. 4,820,911 may be operated according to FIG. 8. This patent may be modified to utilize the teaching of FIGS. 1-7 by inserting a beam splitter Y801 in place of a band pass filter (59, second figure of U.S. Pat. No. 4,820,911), with filters Y802 and Y803 and photodetector Y804. The filters Y802 and Y802 may be either low pass, high pass, or band pass as discussed with reference to FIGS. 1-7. In this example photodetector Y804 would be matched with photodetector Y8-52 for optimum cancellation of the signal component due to ambient illumination.
As another example, the mirror facets such as Y8-24 could be of dual slope, the position of Y8-34 being adjusted downward, e.g., by a beam diameter to maintain a horizontal output beam axis just below center axis Y805. Then a collector corresponding to Y8-54, Y8-52 could be arranged above the horizontal exit beam path Y805 and associated with filter Y803 and photodetector Y804, the beam splitter Y801 being omitted.
d. Description of FIGS. 9, 10, and 11
FIG. 9 shows such a mirror Y9-24 with a second visible laser diode Y9-34A of the same wavelength (or a different wavelength where beam splitters and two pairs of filters and photodetectors are used). The second visible laser diode is mounted in an upper section of the housing and its associated components are shown arranged as a mirror image of the lower components Y8-34, Y846, Y8-54, Y8-56, Y8-64, Y8-70, Y8-74.
The laser diodes Y8-34 and Y9-34A, FIG. 9, could be operated simultaneously in a variable frequency energizing mode, the two output beams Y9-15 and Y9-15A being offset e.g. vertically to provide a double simultaneous scan line for example. The beams could have different configurations, e.g. circular and elliptical, and be activated during respective alternate scans, or the beams could be selectively activated individually, jointly, or alternately by means of manual key selection.
Where the scanner of FIG. 9 is equipped with symbol distance measurement means, e.g. actuated by a key when the marker spots from beam Y9-15 and/or Y9-15A are aligned with a bar code line (or using e.g. one marker beam such as Y9-15 in marker mode), the distance measurement may be used to select which beam to activate, or whether to activate both beams for proximity detect mode.
FIG. 10 shows the beam pattern comprising beam spots Y1015 and Y1015A at a reference plane indicated at Y1020 for the case of two circular beams of equal diameter separated by a center to center distance approximately equal to beam diameter. With this embodiment one half-power beam could be used for close-in scanning, and an automatic distance measurement could control selection of one or two half-power beams (e.g. in a default operating status) for symbol decoding mode and/or proximity detect mode. The distance measurement could be based on time between marginal marker spots in comparison to bar code line width.
It is also conceivable that the beams would produce respective spots Y1115, Y115A as shown in FIG. 11 at a reference plane such as indicated at Y1120. Here again switching between the beams could be based on a distance measurement where dense bar codes are generally in a close up range, and coarser bar codes are generally to be read at greater distances. Where half-power laser diodes are used, both the beams of FIG. 11 could be on simultaneously at relatively great throw distances at least during alternate scans or the like.
As another example, the reflector Y8-54 may be mounted external to housing Y8-10, for example above the housing and facing generally frontally (and without a center aperture), the parts Y801-Y804 and Y8-52 being mounted external to the housing and forwardly of the external reflector to receive reflected light for each successive beam position along a bar code. Where reflectors such as Y8-54 are positioned externally, above and below housing Y8-10, elements Y8-52, Y802 may be forwardly of one reflector and above the housing, while components Y803, Y804 may be located below the housing and forwardly of a second reflector. The reflectors and associated photodetector assemblies may be mounted on an adapter which fits over the front of the housing Y8-10 without obstructing window Y8-48.
e. Description of FIG. 12
In FIG. 12, the output spectrum for a laser diode, e.g. in the infrared region, is indicated at Y1210. Curve Y1211 indicates the relative spectral response of a selenium photovoltaic material while curve Y1212 is for a silicon photovoltaic material. In FIG. 8 or FIG. 9, it is possible that the filters such as Y802, Y803 could be omitted where the photodetectors Y8-52 and Y804 had respective spectral response characteristics as represented at Y1211 and Y1212. A similar result would be possible for a visible laser diode Y8-34 operating at a wavelength of about 0.5 microns (500 nanometers).
Such an approach would also be applicable to the embodiments of FIGS. 1-6, again suggesting that filters such as Y41, Y42, etc. may not be essential to obtaining a substantial degree of ambient light compensation.
f. Exemplary Operation of the Embodiments of FIGS. 8-13
In a mode of operation of the embodiment of FIG. 8 or FIG. 9, alternate scans during reading operation may take place with the laser diode deenergized. The output of the photodetector system such as Y8-52, Y801-Y804 (or 52, 59, in the second figure of U.S. Pat. No. 4,820,911) may be sampled e.g. at a rate many times greater than the maximum information rate, and the result stored for use in modulating the intensity of the laser beam during the next scan so as to tend to compensate further vertical reticle line Y14-21 which is vertical when the laser beam is scanning in a perfectly horizontal plane. It is thus apparent to the user if the beam is not scanning along a path perpendicular to the bars of the bar code. Where the scanner handle is guided by a receiving sheath such as Y981 may be mechanically guided by a universal mount on a fixed support (e.g. a forklift); then it is a simple matter for the user gripping the handle Y9-16 and sheath Y981 to adjust the scanner so reticle Y14-Y21 is essentially parallel to the bars of the bar code. A center marker spot Y13-50 between spots Y13-41, Y3-42, would facilitate visualization of the central part of the bar code through view window Y14-20.
FIG. 14 indicates the use of a linear array Y1462 of photodiode elements Y1463 in front of a straight optical collector Y14-54 (by way of example). A printed circuit board Y1464 may carry the array or arrays and conduct the parallel outputs to suitable processing circuitry such as described with reference to FIGS. 15 and 16. For a uniformly straight reflector configuration (e.g. as represented at 76 in the third figure of incorporated U.S. Ser. No. 07/422,052, with the sensor arrays extending along the axes of elements 35, 36, the second figure), the reflector may comprise two or more straight sections (analogous to elements 35, 36 the second figure of U.S. Ser. No. 07/422,052), with cooperating straight line array sections such as 1462. Each reflector is preferably shaped for optimum efficiency at the maximum range of the scanner.
g. Description of the Embodiment of FIGS. 15 and 16
FIG. 15 is a partial longitudinal sectional view of the scanner of FIG. 8, with a slip-on external photodetector assembly Y1520 applied to the frontal barrel portion of housing Y8-10. FIG. 16 is somewhat diagrammatic horizontal sectional view for illustrating details of the external photodetector assembly Y1520 of FIG. 15 and cooperative parts of the scanner of FIG. 8.
In FIG. 15, upper and lower straight continuous reflected light collectors Y1554 and Y1555 are shown, collector Y1554 being designed to focus reflected light from a near reference plane Y1556 at a photodiode array Y1562 which may correspond identically with array Y1462. Array Y1562 may have a width corresponding to housing Y8-10, e.g. about three inches. Reference numeral Y1511 designates a ray of reflected laser light reflected from a small illuminated spot on a bar code at the near reference plane Y1556.
At a further reference plane Y1557, e.g. representing an optimum plane with respect to scanning of a less dense bar code a reflected light ray Y1512 at the laser wavelength may impinge on a second photodetector array Y1563. A reflected light ray Y1513 from a bar code at an intermediate location indicated at Y1558 is shown as impinging on a further photodiode array Y1582, while a ray Y1514 reflected from a bar code at a farther location is shown as impinging on a further photodiode array Y1583.
The entrances to reflectors Y1554 and Y1555 may be suitably covered by material transparent to the laser wavelength as indicated at Y1585, Y1586. The methods previously described may be used in addition to bandpass filters at Y1585, Y1586, or in places thereof. Thus the arrays Y1562, Y1563, and Y1582, Y1583 may be covered by respective filters as represented in FIG. 2 or FIG. 3, so that the respective differential outputs from the upper and lower photodetector arrays each tends to minimize the effect of ambient light.
Battery power Y1590 can be coupled to the scanner from the subassembly Y1520 via external contact bars embedded in housing Y8-10 and cooperating spring fingers analogous to the fingers (632, seventeenth figure or 801, twenty-fifth figure of incorporated U.S. Ser. No. 07/347,602). In this case, photodetector output signals from detectors Y1562, Y1563, Y1582, Y1583 could also be coupled via such spring fingers and housing contracts to the interior of the scanner.
In this case, the subassembly Y1520 can use its own battery power, e.g. as indicted at Y1590 for supplying power to differential amplifiers and photodetectors for arrays Y1562, Y1563 and Y1582, Y1583. As another example, the difference signals can be converted to optical form e.g. at Y1592, Y1593 for transmission through the margins of window Y8-48 to respective receives Y1594, Y1595.
A battery pack may be used for Y1590 as described in Steven E. Koenck application for patent "Battery Including Electronic Power Saver" U.S. Ser. No. 07/433,076 filed Nov. 7, 1989, Attorney Docket No. 6881.
The assembly Y1520 may be longitudinally adjustable on the barrel of housing Y8-10, a second position of assembly Y1520 being indicated in dot dash outline at Y1520A. The external contact bars embedded in housing Y8-10 may be elongated to maintain engagement with the cooperating spring fingers of assembly Y1520 in the various adjusted positions.
In the embodiment of FIG. 8, a single detector Y8-52 may be used with a rotating filter disk serving to interpose filters such as Y802 and Y803 sequentially and cyclically into the reflected light path at a rate higher than the maximum information rate. The differential between respective pairs of output signals generated by the respective types of filters may be generated, e.g., by a sample-and-hold-circuit for holding a first occurring sample, so that the delayed first signal and a second occurring signal can be supplied simultaneously to a differential amplifier. The output of the differential amplifier can then be sampled during the second signal to generate a sampled bar code output signal compensated for ambient light.
h. Discussion of a Presently Preferred Scanner System with Proximity Detection
The general prior art for actuation of most CCD and laser scanners has required the use of an actuation switch or trigger to initiate operation of the scanner. This method has been used by Norand Corporation for CCD type scanners as shown by incorporated U.S. Pat. No. 4,894,523. See also U.S. Pat. No. 4,282,425 (filed Jul. 25, 1979 and also disclosing proximity detection). Such prior art scanners depend on the operator pulling the trigger or depressing the actuation switch at the correct time, presumably when the reader is correctly positioned in front of the label. If this is the case, the reader will be activated, perform the read and automatically terminate operation quickly and efficiently and subsequently shut down to conserve power. In the case of moving beam laser scanners, it is probably more likely that the operator will press or activate the trigger to generate the reassuring "red stripe" or line and then position the reader so that the "red stripe" reading beam crosses all of the bars for a proper read. When the laser scanner is used in this way, obviously significant power is wasted operating the laser and the motor when no target is available.
It is possible to make an improvement to trigger actuated scanners by adding an electronic proximity sensor to be used either with or without a trigger switch. The idea is to use a sensor that detects the presence of something (such as a label) before the scanner is actuated. If this is used with a trigger operated scanner, the concept would be to actuate the sensor with the trigger switch, and as soon as the sensor detects the presence of a label, the scanner runs. If this is used with a scanner with no trigger, simply placing the reader in front of a label so that the sensor gets the proper indication will cause the scanner to operate. The trigger operated version would be the most power efficient and probably work best because it would include a double indication that reading should occur.
Given some combination of a trigger and a proximity sensor where the trigger causes the proximity sensor to begin operating and the successful sensing by the proximity sensor of a target label causes the scanner to operate, it may be possible to further improve the power efficiency of a scanner such s a moving beam laser type.
i. Supplemental Discussion
Instead of using two detector-filter systems as in FIGS. 8 and 9, it is conceived that a single detector may be used if the light supplied to such single detector from the scan mirror system is alternately that represented by the respective curves Y51, Y52 in FIG. 2, or Y61, Y62, FIG. 3. Thus, with a rotary scan mirror with a plurality of facets as represented at Y91, FIG. 5, or Y8-24, FIG. 8, alternate faces of the scan mirror could be optically coated to reflect the respective bands such as Y51, Y52 or Y61, Y62. The electronics associated with the single detector would then digitally sample and store one scan line and differentially combine it with the corresponding successive samples of the next scan line (e.g. also converted to digital samples) to compensate for ambient light. With this arrangement in FIG. 9, single detector Y8-52 could operate in this manner while beam Y9-15A was off, for example, or each detector of FIG. 9, could operate individually to compensate for ambient light in its particular field of view.
Alternately, it might be possible to coat, e.g., the upper half of each mirror face Y8-21 24, FIG. 8, and to utilize two detectors one above the other for receiving reflected light from the coated and uncoated halves of each mirror, respectively. This could also work with an oscillating mirror collecting reflected light.
It is also conceivable to use rotary facets which are transmissive as to one band of wavelengths such as Y52 and reflective as to another band such as Y50, with one sensor behind the active facet position, and a second sensor in front of such facet position.
It will be apparent that many modifications and variations may be effected without departing from the scope of the novel concepts and teachings of the present invention. | A portable, hand-held data terminal of modular structure includes a base module with a keyboard and a display screen. A data collection and communications module includes a stacked arrangement of a communications interface main circuit board, a radio and a laser scanner assembly which are housed in a housing shell which is attachable to the base module. The radio is mounted in spaced relationship to one side of the main circuit board, while the laser scanner assembly is mounted to the other side of the main circuit board. A support frame and a plurality of ground planes in the sandwiched main circuit board and a routing circuit board form an RF cage for shielding RF interference which may be generated by the radio. Also disclosed is a method for reducing the operational power consumption requirements of laser bar code scanners by analyzing reflected laser light in order to determine the presence of optically readable information sets. In a first embodiment, the reflected light intensity of a pulsed laser light beam is compared to the ambient light intensity to provide a control signal to actuate the scanning mode if a threshold differential is satisfied. In a second embodiment, a modulated laser light pulse is filtered to remove ambient light noise and then provides a control signal to actuate the scanning mode if a threshold value is reached. | 8 |
This Application is a Divisional of application Ser. No. 09/514,364 filed Feb. 28, 2000 now U.S. Pat. No 6,201,754. Priority of Application Ser. No. 11-248580, filed on Sep. 2, 1999 in Japan, is claimed under 35 USC 119. The certified priority document was filed in Ser. No. 09/514,364 on Feb. 28, 2000.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor memory device, and more specifically, it relates to a semiconductor memory device having a structure capable of supplying a stable power supply voltage.
2. Description of the Prior Art
The structure of a conventional semiconductor memory device 9000 is described with reference to FIG. 20 . The semiconductor memory device 9000 shown in FIG. 20 has an internal circuit group 990 including memory cells and a synchronous circuit 995 generating an internal clock. The synchronous circuit 995 is driven by an operation start trigger signal and generates the internal clock deciding operation timing in the internal circuit group 990 . The synchronous circuit 995 is formed by a PLL circuit or the like, for example.
As shown in FIG. 20, the synchronous circuit 995 and the internal circuit group 990 share a power source 900 , to operate with a power supply voltage received from the power source 900 and a ground voltage GND as operating voltages.
The operating voltages must be stable so that the synchronous circuit 995 performs a synchronous operation in high precision.
When the internal circuit group 990 operates, however, noise originates following current consumption to disadvantageously swing the power supply voltage. In the structure of the conventional semiconductor memory device 9000 , therefore, precision of the internal clock is disadvantageously damaged following the internal operation.
When the internal circuit group 990 is defective, the power supply voltage or a signal voltage similarly swings. Therefore, influence following a failure of the internal circuit group 990 must be suppressed not only for circuits in the same chip but also for another device connected through the same wire.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a semiconductor memory device having a large operation margin in a high-frequency operation by supplying a stable power supply voltage.
Another object of the present invention is to provide a semiconductor memory device capable of guaranteeing a stable operation of an apparatus connected through the same wire while suppressing influence exerted by a failure.
A semiconductor memory device according to an aspect of the present invention comprises an internal circuit including a memory cell array, a voltage supply node, a synchronous circuit operating on the basis of an operating voltage received from the voltage supply node for generating an internal clock deciding operation timing of the internal circuit, a power source for supplying a voltage to the internal circuit and the voltage supply node, and a voltage stabilizing circuit stabilizing the voltage of the voltage supply node.
Preferably, the voltage stabilizing circuit includes a detection circuit detecting change of the voltage of the voltage supply node and a circuit supplying the voltage from the power source to the voltage supply node in response to an output of the detection circuit.
According to the aforementioned semiconductor memory device, therefore, a precise synchronous operation is guaranteed by arranging a circuit eliminating power supply noise and supplying a stable operating voltage to the synchronous circuit also when the synchronous circuit and the internal circuit use the same power source.
Preferably, the power source includes a first power source corresponding to a first voltage and a second power source supplying a second voltage lower than the first voltage, the voltage supply node includes a first voltage supply node corresponding to the first power source and a second voltage supply node corresponding to the second power source, the voltage stabilizing circuit is provided between the first power source and the first voltage supply node, and the semiconductor memory device further comprises a dummy current generation circuit feeding a dummy current from the first voltage supply node to the second voltage supply node at prescribed timing. More preferably, the dummy current generation circuit includes a transistor provided between the first voltage supply node and the second voltage supply node and rendered conductive at prescribed timing.
The dummy current is fed between the power source supplying an internal voltage to the synchronous circuit and a GND side. Thus, the operation of the detection circuit (differential amplifier) arranged on the side of the power source for detecting change of the operating voltage is stabilized.
Preferably, the power source includes a first power source corresponding to a first voltage and a second power source supplying a second voltage lower than the first voltage, the voltage supply node includes a first voltage supply node corresponding to the first power source and a second voltage supply node corresponding to the second power source, the voltage stabilizing circuit is provided between the first power source and the first voltage supply node, and the semiconductor memory device further comprises a high impedance element raising the impedance between the second voltage supply node and the second power source.
A high impedance component is arranged on the GND side, thereby preventing a ground voltage from mixture with noise.
Preferably, the semiconductor memory device further comprises a voltage change circuit provided between the first voltage supply node and the second voltage supply node for changing the voltages of the first and second voltage supply nodes in the same direction. More preferably, the voltage change circuit includes a capacitive element provided between the first voltage supply node and the second voltage supply node.
The operating voltage of the synchronous circuit can be kept constant by changing the power source side and the GND side in the same direction.
More preferably, the semiconductor memory device further comprises a filter provided between the power source and the voltage stabilizing circuit.
A more stable operating voltage can be supplied to the synchronous circuit by serially connecting the filters between the power source and the synchronous circuit.
A semiconductor memory device according to another aspect of the present invention comprises a pin, an internal circuit, including a memory cell array, operating on the basis of an input from the pin, and a leakage current prevention circuit provided between the pin and the internal circuit for detecting a leakage current from the internal circuit and electrically disconnecting the pin and the internal circuit from each other.
Preferably, the leakage current prevention circuit includes a detection circuit detecting change of an operating voltage of the internal circuit following the leakage current, and a circuit electrically disconnecting the pin and the internal circuit from each other in response to an output of the detection circuit.
Therefore, the aforementioned semiconductor memory device detects an abnormal current (leakage current) generated in the internal circuit and disconnects the pin and the internal circuit from each other. Thus, influence exerted on an external device by the leakage current can be suppressed.
More preferably, the circuit includes a voltage supply circuit supplying an operating voltage to the internal circuit on the basis of a voltage supplied from the pin, and the voltage supply circuit stops supply of the operating voltage to the internal circuit in response to the output of the detection circuit.
Operations of another chip using the same power supply line can be guaranteed by stopping supply of the operating voltage on the basis of a result of detection of the leakage current.
A semiconductor memory device according to still another aspect of the present invention comprises a pin receiving an input from an external device, an internal circuit, including a memory cell array, operating in response to an input from the pin in a normal mode, a voltage supply node, a synchronous circuit operating on the basis of an operating voltage received from the voltage supply node for generating an internal clock deciding operation timing of the internal circuit, and a voltage supply control circuit supplying a voltage from the pin to the voltage supply node in a test mode.
Thus, the aforementioned semiconductor memory device employs the pin used in the normal mode as a power supply pin for the synchronous circuit in the test mode. When a plurality of chips receive the same signal or voltage through the same signal line or power supply line and a leakage current is generated in any of the chips, for example, reduction of the voltage level of the signal line or the power supply line can be prevented by stopping activation of circuits included in the defective chip.
Preferably, the pin includes a first pin corresponding to a first voltage and a second pin supplying a second voltage lower than the first voltage, the voltage supply node includes a first voltage supply node corresponding to the first pin and a second voltage supply node corresponding to the second pin, and the voltage supply control circuit includes a first voltage supply control circuit supplying the voltage from the pin to the first voltage supply node in the test mode and a second voltage supply control circuit supplying the voltage from the pin to the second voltage supply node in the test mode. More preferably, the first voltage supply control circuit operates to stabilize the voltage of the first voltage supply node, and the second voltage supply control circuit operates to stabilize the voltage of the second voltage supply node.
The operating voltage can be stably supplied to the synchronous circuit in the test mode by providing control circuits for supplying the voltage on a power supply side and a GND side respectively.
Preferably, the voltage supply control circuit includes a generation circuit generating a prescribed signal in the test mode, and a switching circuit supplying the input from the pin to the synchronous circuit and an output of the generation circuit to the internal circuit respectively in the test mode while supplying the input from the pin to the internal circuit in the normal mode. More preferably, the switching circuit includes a first switch provided between the pin and the synchronous circuit and turned on in the test mode, a second switch provided between the pin and the internal circuit and turned on in the normal mode, and a third switch provided between the generation circuit and the internal circuit and turned on in the test mode.
In the test mode, the input received from the pin can be supplied to the synchronous circuit as a power supply voltage by employing the internally generated signal in place of a signal received from the normally used pin.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram for illustrating the structure of a principal part of a semiconductor memory device according to a first embodiment of the present invention;
FIG. 2 is a timing chart for illustrating operations of a synchronous circuit 101 ;
FIG. 3 is a diagram for illustrating another structure of the principal part of the semiconductor memory device according to the first embodiment of the present invention;
FIG. 4 is a diagram for illustrating the structure of a principal part of a semiconductor memory device according to a second embodiment of the present invention;
FIG. 5 is a schematic diagram for illustrating a parallel test on a plurality of chips mounted on the same board;
FIGS. 6 and 7 are diagrams for illustrating structures of a principal part of a semiconductor memory device according to a third embodiment of the present invention;
FIG. 8 is a diagram for illustrating another exemplary structure of a circuit for detecting a leakage current;
FIG. 9 illustrates the relation between check currents and internal voltages in normal and defective chips respectively;
FIG. 10 is a diagram for illustrating still another exemplary structure of the circuit for detecting a leakage current;
FIG. 11 is a diagram showing a circuit structure for latching an output of a comparator 127 ;
FIG. 12 is a diagram for illustrating a semiconductor memory device according to a fourth embodiment of the present invention;
FIG. 13 is a diagram for illustrating a logic circuit block 1001 shown in FIG. 12;
FIG. 14 is a diagram showing an exemplary structure of a memory core part 1000 shown in FIG. 12;
FIG. 15 is a diagram for illustrating the structure of a memory part 20 ;
FIG. 16 is a diagram showing an outline of the structure of a reference voltage control circuit 13 ;
FIG. 17 is a diagram showing an exemplary structure of the reference voltage control circuit 13 ;
FIGS. 18 and 19 are diagrams showing exemplary association between a synchronous circuit 101 and an internal circuit group 102 ; and
FIG. 20 is a diagram for illustrating a power source in a conventional semiconductor memory device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention are now described with reference to the drawings. Parts identical or corresponding to each other are denoted by the same reference numerals, and redundant description is not repeated.
[First Embodiment]
The structure of a semiconductor memory device according to a first embodiment of the present invention is described with reference to FIG. 1 . The semiconductor memory device shown in FIG. 1 comprises a synchronous circuit 101 , an internal circuit group 102 , a delay circuit 103 and a one-shot pulse generation circuit 104 .
The synchronous circuit 101 is formed by a PLL (phase locked loop) circuit, a DLL (delay locked loop) circuit or the like. The synchronous circuit 101 is activated by an operation start trigger signal (a clock enable signal CKE going high upon activation of a chip in an SDRAM), initialized by an initialization pulse and thereafter generates an internal clock in response to a reference clock (e.g., an external clock).
The delay circuit 103 delays and outputs the operation start trigger signal. The one-shot pulse generation circuit 104 generates a one-shot initialization pulse in response to the output from the delay circuit 103 . When a power supply voltage VCC goes high at a time t0, the clock enable signal CKE forming the operation start trigger signal goes high at a time t1, as shown in FIG. 2 . Thus, the one-shot initialization pulse is generated. The synchronous circuit 101 starts a synchronous operation upon application of the initialization pulse, and generates the internal clock.
Referring again to FIG. 1, the synchronous circuit 101 and the internal circuit group 102 are arranged between a power source 100 and a ground power source (ground voltage) GND. For simplifying the illustration, the power source 100 and the ground power source GND are hereinafter referred to as a power supply side and a GND side respectively. The internal circuit group 102 is formed by a memory cell array, a circuit controlling the operation of the memory cell array, an input/output buffer and the like.
Exemplary association between the synchronous circuit 101 and the internal circuit group 102 is described with reference to FIG. 18 . FIG. 18 shows an SDRAM including a clock buffer 1101 capturing an external clock ext.CLK and outputting an internal clock, a control signal buffer 1102 capturing an external control signal (e.g., a row address strobe signal /RAS) on the basis of the output from the clock buffer 1101 , an address buffer 1103 capturing an address signal A on the basis of the output from the clock buffer 1101 , a control circuit 1104 selecting a memory cell on the basis of the output from the clock buffer 1101 in response to outputs of the control signal buffer 1102 and the address buffer 1103 , a memory cell array 1105 including a plurality of memory cells, an input/output buffer 1106 connected with a data input/output pin DQ for outputting data from the selected memory cell or externally receiving data written in the selected memory cell, and an internal clock signal generation circuit 1110 receiving the external clock ext.CLK and generating an internal clock CLK repeating high and low states in a desired phase. Symbols VCC and VSS denote power supply pins. The input/output buffer 1106 operates with reference to the internal clock CLK. The internal clock signal generation circuit 1110 is formed by a PLL circuit or a DLL circuit. The synchronous circuit 101 shown in FIG. 1 corresponds to the internal clock signal generation circuit 1110 , for example.
Referring again to FIG. 1, a VDC (voltage down convertor) circuit 200 including a differential amplifier 105 and a PMOS transistor 106 is arranged on the power supply side (voltage supply node NA) of the synchronous circuit 101 . The synchronous circuit 101 is supplied with an internal voltage from the node NA through the VDC circuit 200 .
The PMOS transistor 106 is connected between the power source 100 and the node NA. The differential amplifier 105 has a positive input terminal connected with the node NA and a negative input terminal supplied with a reference voltage vref. The differential amplifier 105 is activated in response to the clock enable signal CKE and operates on the basis of a voltage supplied from the power source 100 . The PMOS transistor 106 is rendered conductive in response to an output of the differential amplifier 105 .
An NMOS transistor 109 for generating impedance is arranged on the GND side (voltage supply node NB) of the synchronous circuit 101 . The NMOS transistor 109 is connected between the ground power source GND and the node NB, and supplied with the power supply voltage in its gate.
A capacitor 107 is arranged between the nodes NA and NB for stabilizing the voltage supplied to the synchronous circuit 101 . The capacitor 107 may be formed by a parallel flat capacitor, a MOS capacitor, a junction capacitor or a memory cell capacitor corresponding to a DRAM.
A PMOS transistor 108 for feeding a dummy current is arranged between the node NA and the ground power source GND. The PMOS transistor 108 is rendered conductive in response to an inverted clock enable signal /CKE obtained by inverting the clock enable signal CLK.
A VDC circuit 210 including a differential amplifier 110 and a PMOS transistor 111 is arranged on the power supply side (voltage supply node NC) of the internal circuit group 102 . The internal circuit group 102 is supplied with an internal voltage from the node NC through the VDC circuit 210 .
The PMOS transistor 111 is connected between the power source 100 and the node NC. The differential amplifier 110 has a positive input terminal connected with the node NC and a negative input terminal supplied with the reference voltage vref. The PMOS transistor 111 is rendered conductive in response to an output of the differential amplifier 110 . A capacitor 112 is arranged between the node NC and the ground power source GND.
The VDC circuit 200 and 210 are thus arranged on the power supply side thereby preventing the voltage of the voltage supply node NA from vibrating in association with noise generated following the operation of the internal circuit group 102 . Thus, the synchronous circuit 101 can be supplied with a stable voltage.
Also when the node NA is influenced by noise, the voltages of the nodes NA and NB can be changed in the same direction due to the coupling effect of the capacitor 107 arranged between the power supply side and the GND side of the synchronous circuit 101 . In other words, the operating voltage (voltage between the nodes NA and NB) of the synchronous circuit 101 is kept constant.
Further, the operation of the differential amplifier 105 for generating the voltage of the node NA is stabilized due to the provision of the path (the presence of the PMOS transistor 108 ) for feeding the dummy current. The differential amplifier 105 can stably operate against noise.
The synchronous circuit 101 operates in a chip active period when the clock enable signal CKE goes high. Therefore, the dummy current, which is fed in response to the clock enable signal CKE, is cut while the clock enable signal CKE is low (power down state) for reducing current consumption. Thus, the inverted clock enable signal /CKE is supplied to a gate electrode of the PMOS transistor 108 .
The GND side may also be influenced by noise. Therefore, the ON-state NMOS transistor 109 is arranged. The node NB is prevented from influence by noise through such on-state resistance. The NMOS transistor 109 raises the impedance of the node NB, thereby causing the coupling effect by the capacitor 107 .
Another exemplary structure in the first embodiment of the present invention is described with reference to FIG. 3 . The structure shown in FIG. 3 includes a PMOS transistor 113 , arranged between a power source 100 and a VDC circuit 200 , receiving a ground voltage GND in its gate.
A filter utilizing on-state resistance of the PMOS transistor 113 is arranged for the power source 100 supplying a voltage to the VDC circuit 200 . The VDC circuit 200 serves as a filter for a synchronous circuit 101 against the power source 100 .
Thus, two filters are serially arranged between the power source 100 and a node NA. Consequently, not only noise in a high-frequency operation but also noise over a wide frequency domain can be cut.
[Second Embodiment]
The structure of a semiconductor memory device according to a second embodiment of the present invention is described with reference to FIG. 4 . After packaging a chip, it is difficult to separately provide an input pin for supplying a new power supply voltage to a test-system circuit. According to the second embodiment of the present invention, a normally used pin (pin used in a mode other than a test mode) is employed as a power supply pin for the test-system circuit. In the second embodiment of the present invention, a synchronous circuit 101 formed by a DLL circuit or the like outputs an internal clock, which is used only in the test mode (the output of the synchronous circuit 101 is hereinafter referred to as an internal test clock).
A VDC circuit 200 , a capacitor 118 and a PMOS transistor 114 are arranged on a power supply side of the synchronous circuit 101 . According to the second embodiment of the present invention, a differential amplifier 105 included in the VDC circuit 200 operates in response to a test mode signal TEST. A PMOS transistor 106 is connected between a node NA and one conducting terminal of the PMOS transistor 114 . The capacitor 118 is connected between the node NA and a ground voltage GND.
The PMOS transistor 114 is connected between a signal input pin PA receiving a signal A and the PMOS transistor 106 . The PMOS transistor 114 is rendered conductive in response to a test mode signal /TEST obtained by inverting the test mode signal TEST.
An NMOS transistor 116 is arranged on a GND side of the synchronous circuit 101 . The NMOS transistor 116 is connected between a node NB and a signal input pin PB, and rendered conductive in response to the test mode signal TEST.
In the structure shown in FIG. 4, the synchronous circuit 101 operates when the test mode signal TEST goes high (a specific test mode) and outputs the internal test clock.
A circuit 115 provided for the signal input pin PA captures the signal A in response to the test mode signal /TEST and outputs an internal signal. A circuit 117 provided for the signal input pin PB captures a signal B in response to the test mode signal /TEST and outputs an internal signal. An internal circuit group 102 operates in response to the internal signal in a normal operation mode. A power supply structure for the internal circuit group 102 is identical to that described with reference to the first embodiment.
The signal input pin PA is supplied with the signal A for a normal internal signal system (circuit 115 ) in the normal mode and supplied with the signal A of the power supply voltage level in the test mode. The signal input pin PB is supplied with the signal B corresponding to a normal internal signal system (circuit 117 ) in the normal mode and supplied with the signal B of the ground voltage level in the test mode.
Thus, the signal input pins PA and PB can be used as power supply pins for the synchronous circuit 101 defining the test-system circuit. In this case, the internal signals are internally generated if necessary. Alternatively, a pin corresponding to an internal signal not used in the test mode is used as a power supply pin.
Exemplary association between the synchronous circuit 101 and the internal circuit group 102 is described with reference to FIG. 19 . In a semiconductor memory device shown in FIG. 19, a logic circuit block 1120 electrically interfacing with an external device, a memory core part 1122 including a memory cell array 1126 transmitting/receiving signals to/from the logic circuit block 1120 are formed on the same substrate. The logic circuit block 1120 transmits/receives signals to/from a device (not shown) through a plurality of external pins P 0 to Pn. The memory core part 1122 includes the memory cell array 1126 , a data input/output circuit 1128 , a controller 1124 controlling operations of the memory cell array 1126 and the data input/output circuit 1128 on the basis of signals received from the logic circuit block 1120 and an internal clock signal generation circuit 1130 . The internal clock signal generation circuit 1130 generates an internal test clock in a test mode. For example, the controller 1124 and the data input/output circuit 1128 operate with reference to the internal test clock output from the internal clock signal generation circuit 1130 in the test mode.
In the test mode for the memory cell array 1126 , no signal may be input in the logic circuit block 1120 . After writing data once, for example, no pin is required for inputting data. At this time, signal supply on the side of the logic circuit block 1120 can be stopped. Therefore, the signal input pins P 0 and P 1 used for circuit operations of the logic circuit block 1120 in a normal mode are used as power supply pins for the internal clock signal generation circuit 1130 , generating the internal test clock in the test mode, included in the memory core part 1122 .
The power supply structure for the synchronous circuit 101 is applicable not only to the synchronous circuit 101 but also to all test-system circuits driven only in a test mode.
Thus, power supply pins in the test-system circuit can be dedicated by employing normally used pins not used in the test mode as power supply pins for the test-system circuit. Consequently, the test-system circuit is stabilized in operation, whereby a precise synchronous operation is implemented particularly in the synchronous circuit.
[Third Embodiment]
A parallel test for simultaneously testing a plurality of semiconductor memory devices mounted on the same board is now described. FIG. 5 is a schematic diagram for illustrating the parallel test testing a plurality of chips mounted on the same board. Symbols L 0 # 0 to L 0 # 2 denote signal lines and symbols L 1 # 0 to L 1 # 2 and L 2 # 0 to L 2 # 2 denote power supply lines respectively.
A plurality of chips mounted on the same board and subjected to a parallel test share a power source and a signal (row address strobe signal RAS or the like). FIG. 5 representatively shows a plurality of chips 120 # 0 to 120 # 11 sharing the signal lines L 0 # 0 to L 0 # 2 and the power supply lines L 1 # 0 to L 1 # 2 and L 2 # 0 to L 2 # 2 .
The signal lines L 0 # 0 to L 0 # 2 are coupled with each other and transmit the same signal to the chips 120 # 0 to 120 # 11 . The power supply lines L 1 # 0 to L 1 # 2 are coupled with each other and supply a voltage of the same level to the chips 120 # 0 to 120 # 11 . Similarly, the power supply lines L 2 # 0 to L 2 # 2 are coupled with each other and supply a voltage of the same level to the chips 120 # 0 to 120 # 11 .
If part of the chips 120 # 0 to 120 # 11 is defective, the voltage of the shared power supply lines L 11 # 0 to L 1 # 2 and L 2 # 0 to L 2 # 2 or the voltage level of the shared signal lines L 0 # 0 to L 0 # 2 is reduced in the parallel test due to a leakage current flowing from this chip into the signal lines L 0 # 0 to L 0 # 2 or the power supply lines L 1 # 0 to L 1 # 2 and L 2 # 0 to L 2 # 2 . Such change of the voltage level disadvantageously influences the results of the test. In other words, a correct test cannot be made.
Therefore, circuits for coping with generation of an abnormal current (leakage current) for each chip are provided as shown in FIG. 6. A circuit structure according to a third embodiment of the present invention shown in FIG. 6 is now described.
A comparator 127 is arranged for comparing the voltage of a node NC with a prescribed voltage (vref/2 in FIG. 6 ). A differential amplifier 110 of a VDC circuit 210 operates in response to an output of an AND circuit 128 receiving an output from an output node NX of the comparator 127 and a clock enable signal CKE.
A VDC circuit 130 is arranged for the node NC. The VDC circuit 130 includes a differential amplifier 131 and a PMOS transistor 132 . The differential amplifier 131 has a positive input terminal connected with the node NC and a negative input terminal supplied with a reference voltage vref The PMOS transistor 132 is connected between a power source and the node NC and rendered conductive in response to an output of the differential amplifier 131 . The VDC circuit 130 is previously formed to be capable of limiting the quantity of current suppliable to an internal circuit group 102 .
A differential amplifier 105 of a VDC circuit 200 operates in response to an output of an AND circuit 124 receiving the output of the node NX and a test mode signal TEST.
When executing a parallel test on the plurality of chips in the arrangement shown in FIG. 5, the VDC circuit 130 is turned on while turning off the VDC circuits 200 and 210 for normal operations in a standby state. The “standby state” indicates a state after starting the parallel state and before activating the chips 120 # 0 to 120 # 11 .
When the chip is normal, the VDC circuit 130 can normally supply an internal voltage. Therefore, the voltage of the node NX goes high due to comparison of the voltage of the node NC and the prescribed voltage vref/2. Consequently, the VDC circuit 210 for a normal operation is turned on when the chip is activated. When entering a specific test mode (the signal TEST goes high), the VDC circuit 200 is turned on to activate the synchronous circuit 101 .
If the internal circuit group 102 is defective and generates a leakage current, however, the VDC circuit 130 cannot supply a sufficient current for supplementing the leakage current. Therefore, the voltage of the node NC is reduced. The voltage of the node NX goes low due to comparison of the voltage of the node NC and the prescribed voltage vref/2. In other words, generation of the leakage current is detected.
When the leakage current is detected, the VDC circuit 210 is not turned on to activate the internal circuit group 102 even if the chip is activated. Also when entering the specific test mode (the signal TEST goes high), the VDC circuit 200 is not turned on to activate the synchronous circuit 101 .
Therefore, the VDC circuits 210 and 200 are turned off for a defective chip in the parallel test. Thus, the remaining chips sharing the power supply lines and the signal lines can be prevented from influence by generation of the leakage current.
When outputting presence/absence of generation of the leakage current, an output latch 122 is so formed as to latch data (data read from a memory cell) received from a general path and a signal of the node NX indicating presence/absence of generation of the leakage current (output of the comparator 127 ). Thus, presence/absence of generation of the leakage current is output through an output buffer 123 receiving data from the output latch 122 .
While the determination level in the comparator 127 is vref/2 in the above description, the determination level is not restricted to this but can be arbitrarily set. A voltage for the determination level in the comparator 127 may be externally input or may be internally generated at an arbitrary level.
The structure of the VDC circuit 130 is not restricted to that shown in FIG. 6 but a structure shown in FIG. 7 is also employable. Referring to FIG. 7, a VDC circuit 135 including PMOS transistors 136 and 137 is arranged in place of the VDC circuit 130 . The PMOS transistor 136 is connected between a power source and a node receiving an input from outside the chip, while the PMOS transistor 137 is connected between the power source and a node NC. Gates of the PMOS transistors 136 and 137 receive a signal from outside the chip. The PMOS transistors 136 and 137 form a current mirror circuit. Thus, the value of a check current for checking a leakage current can be switched by an external input.
The VDC circuits 130 and 135 shown in FIGS. 6 and 7 are dedicated for leakage current detection. It is also possible to apply a general VDC circuit for supplying a small standby current provided on a chip to leakage current detection.
FIG. 8 shows an exemplary VDC circuit for supplying a small standby current. The circuit shown in FIG. 8 includes a differential amplifier 131 and circuits 141 and 144 .
The circuit 141 includes a PMOS transistor 142 rendered conductive in response to an external set switching signal and a PMOS transistor 143 rendered conductive in response to an output of the differential amplifier 131 . The PMOS transistors 142 and 143 are serially connected between a power source and the node NC.
The circuit 144 includes a PMOS transistor 145 rendered conductive in response to the external set switching signal and a PMOS transistor 146 rendered conductive in response to the output of the differential amplifier 131 . The PMOS transistors 145 and 146 are serially connected between the power source and the node NC.
Suppliability to the node NC is switched by selectively activating the circuits 141 and 144 in response to the set switching signal.
When a leakage current is generated, an internal voltage is reduced due to insufficient current supply for holding the internal voltage. At this time, the internal voltage abruptly changes from a certain check current value, as shown in FIG. 9 . Therefore, a defective chip can be readily detected by properly setting the check current value.
In the aforementioned structure, the VDC circuits 200 and 210 do not operate in chip activation (specific timing) due to reduction of the internal voltage detected in the standby state. However, the present invention is not restricted to this but the detection may be performed in a prescribed test mode for latching the result of this detection so that the VDC circuits 200 and 210 are not turned on in chip activation.
For example, the differential amplifier 131 is driven in response to a test mode signal ITST specifying a specific test mode, as shown in FIG. 10 . The “test mode” indicates a mode for a current check test, which is different from the test mode in the parallel test.
FIG. 11 illustrates a circuit structure for latching the output of the comparator 127 . Referring to FIG. 11, a switch 150 , an invertor 151 , a NAND circuit 152 and an invertor 153 are arranged for the comparator 127 . The switch 150 is turned in response to the test mode signal ITST for connecting a latch circuit formed by the invertor 151 and the NAND circuit 152 with the output of the comparator 127 . The NAND circuit 152 forming the latch circuit is reset in response to a reset signal RESET. The invertor 153 inverts an output of the latch circuit. The differential amplifier included in the VDC circuit is driven in response to the output of the invertor 153 .
Thus, the semiconductor memory device according to the third embodiment of the present invention can detect a leakage current of a defective chip and prevent the leakage current from flowing out. Therefore, operations of the remaining chips arranged on the same board are guaranteed particularly in a parallel test.
[Fourth Embodiment]
An outline of a semiconductor memory device according to a fourth embodiment of the present invention is described with reference to FIGS. 12 to 15 . In the following description, it is assumed that signals provided with symbol “/” are those obtained by inverting signals provided with no such symbol “/”.
As shown in FIG. 12, the semiconductor memory device according to the fourth embodiment of the present invention comprises a memory core part 1000 including a DRAM (dynamic random access memory) and a logic circuit block 1001 . The memory core part 1000 and the logic circuit block 1001 are formed on the same chip 1002 . An SRAM, a gate array, an FPGA, a nonvolatile RAM, a ROM and the like are also carried on the chip 1002 , although these elements are not illustrated.
As shown in FIG. 13, the logic circuit block 1001 and the memory core part 1000 transmit/receive signals through connection nodes 2 a to 2 m . The logic circuit block 1001 transmits commands, addresses and data to the DRAM, while the DRAM responsively transmits data to the logic circuit block 1001 .
The logic circuit block 1001 receives an external clock signal CLK, a command CMD and a reference voltage vref from pins 1 a , 1 b and 1 d respectively. The logic circuit block 1001 further inputs/outputs data DATA through a pin 1 c.
The logic circuit block 1001 logically processes input signals and outputs corresponding signals to the memory core part 1000 . The reference voltage vref received through the pin 1 d is output to the node 2 m as such.
As shown in FIG. 14, the memory core part 1000 is supplied with the following signals through the connection nodes 2 a to 2 k : The node 2 a supplies clock signals CLK and /CLK. The node 2 b supplies a clock enable signal CKE. The node 2 c supplies control signals, i.e., a signal ROWA indicating activation of a word line, a signal PC related to resetting (precharging) of the word line, a signal READ related to a read operation of a column related circuit, a signal WRITE related to a write operation of the column related circuit, a signal APC instructing an auto precharge operation, a signal REF related to a refresh operation and signals SRI and SWO related to a self refresh mode.
Four commands of the signals ROWA, PC, READ, WRITE in total can be simultaneously generated at the maximum.
The node 2 d supplies act bank signals AB 0 to AB 7 . The act bank signals AB 0 to AB 7 specify banks to be accessed in access to row and column respectively. The node 2 e supplies precharge bank signals PB 0 to PB 7 . The node 2 f supplies read bank signals RB 0 to RB 7 , and the node 2 g supplies write bank signals WB 0 to WB 7 .
The node 2 h supplies act address signals AA 0 to AA 10 , the node 2 i supplies read address signals RA 0 to RA 5 , and the node 2 j supplies write address signals WA 0 to WA 5 .
The node 2 k supplies input data DI 0 to DI 511 . Output data DQ 0 to DQ 511 from the memory core part 1000 are transmitted to the logic circuit block 1001 through the node 21 .
The memory core part 1000 includes buffers 3 a to 31 , a mode decoder 4 , an act bank latch 5 d , a precharge bank latch 5 e , a read bank latch 5 f , a write bank latch 5 g , a row address latch 5 h , a read address latch 5 i , a write address latch 5 j , a self refresh timer 6 , a refresh address counter 7 , a multiplexer 8 , predecoders 9 , 10 and 11 , a mode register 12 , a reference voltage control circuit 13 and a synchronous circuit 14 .
The buffer 3 a receives the clock signals CLK and /CLK and outputs internal clock signals int.CLK and /int.CLK. Each of the buffers 3 c to 3 k is supplied with the reference voltage vref from the reference voltage control circuit 13 . The buffer 3 b receives the clock enable signal CKE. The buffer 3 c operates in response to an output of the buffer 3 b and captures the control signals received in the node 2 c . The mode decider 4 receives an output of the buffer 3 c and outputs internal control signals (signals ROWA, COLA, PC, READ, WRITE, APC and SR).
The act bank latch 5 d latches the act bank signals AB 0 to AB 7 through the buffer 3 d . The precharge bank latch 5 e latches the precharge bank signals PB 0 to PB 7 through the buffer 3 e . The read bank latch 5 f latches the read bank signals RB 0 to RB 7 through the buffer 3 f . The write bank latch 5 g latches the write bank signals WB 0 to WB 7 through the buffer 3 g . The row address latch 5 h latches the act address signals AA 0 to AA 10 through the buffer 3 h . The read address latch 5 i latches the read address signals RA 0 to RA 5 through the buffer 3 i . The write address latch 5 j latches the write address signals WA 0 to WA 5 through the buffer 3 j.
The buffer 3 k captures the input data DI 0 to DI 511 . The buffer 31 captures data output from a data input/output circuit 15 and outputs the same to the node 21 .
The self refresh timer 6 receives the signal SR output from the mode decoder 4 and starts an operation. The refresh address counter 7 generates an address for performing a refresh operation in accordance with an instruction of the self refresh timer 6 . The multiplexer 8 outputs the output from the row address latch 5 h in a normal operation, while outputting the output of the refresh address counter 7 in a self refresh operation. The predecoder 9 predecodes a row address received from the multiplexer 8 . The predecoder 10 decodes a column address received from the read address latch 5 i . The predecoder 11 decodes a column address received from the write address latch 5 j . The mode register 12 holds information (e.g., data corresponding to a burst length) corresponding to a prescribed operation mode in response to the output of the row address latch 5 h.
A global data bus GIO 1 transmits data read from a memory part 20 to the data input/output,circuit 15 . A global data bus GIO 2 transmits input data received in the data input/output circuit 15 to the memory part 20 .
The memory part 20 is divided into banks BANK 0 to BANK 7 , as shown in FIG. 15 . Each bank includes a plurality of memory cells arranged in rows and columns, a plurality of word lines arranged in correspondence to the rows, and a plurality of bit lines arranged in correspondence to the columns. Each memory cell is formed by a memory cell capacitor storing information in the form of charges and a memory cell transistor having a gate electrode connected with a corresponding word line, a first conducting terminal connected with a corresponding bit line and a second conducting terminal connected with the memory cell capacitor.
A row decoder 21 and a column decoder 22 are arranged for each bank. The row decoder 21 selects a corresponding row direction in response to the output of the predecoder 9 . The column decoder 22 selects the corresponding column direction in response to the outputs of the predecoders 10 and 11 .
The banks BANK 0 to BANK 7 transmit/receive data to/from the global data buses GIO 1 and GIO 2 through an I/O port 23 .
Each bank is controlled by a bank address. The bank address exists in correspondence to each command. For example, a word line of the corresponding bank is activated in accordance with the signal ROWA and the act bank signal ABn (n=0 to 7). The word line of the corresponding bank is reset in accordance with the signal PC and the precharge bank signal PBn (n=0 to 7). Data is read from a sense amplifier of the corresponding bank in accordance with the signal READ and the read bank signal RBn (n=0 to 7). Data is written in the sense amplifier of the corresponding bank in accordance with the signal WRITE and the write bank signal WBn (n=0 to 7).
The relation between the reference voltage control circuit 13 and the synchronous circuit 14 is now described. The synchronous circuit 14 formed by a PLL circuit or the like generates an internal test clock in a test mode.
In the test mode, the memory core part 1000 operates with reference to the internal test clock in place of the internal clock int.CLK output from the buffer 3 a , for example. Alternatively, a partial circuit (data input/output circuit 15 ) operates with reference to the internal test clock in place of the internal clock int.CLK.
As shown in FIG. 16, the reference voltage control circuit 13 includes a vref generation circuit 40 and a switching circuit 41 . The vref generation circuit 40 generates a reference voltage in response to the test mode signal TEST.
In the test mode, the switching circuit 41 connects the pin 1 d (node 2 m ) with a power supply line L 3 for supplying a voltage to the synchronous circuit 14 and electrically connects an internal vref line L 4 supplying the reference voltage to the buffers 3 c to 3 k with an output node of the vref generation circuit 40 . In a normal mode, the switching circuit 41 electrically connects the pin 1 d with the internal vref line L 4 .
In the normal mode, the reference voltage vref input from the pin 1 d (external) decides the threshold voltages of the input buffers 3 c to 3 k . At this time, the synchronous circuit 14 , which is a test-system circuit, is stopped. In the test mode, the pin 1 d is used as a pin for supplying a power supply voltage to the synchronous circuit 14 . At this time, the internally generated reference voltage is supplied to the buffers.
A specific example of the reference voltage control circuit 13 is described with reference to FIG. 17 . The switching circuit 41 is formed by NMOS transistors 30 , 31 and 32 . Each of the NMOS transistors 30 and 32 receives the test mode signal TEST in its gate, while the NMOS transistor 31 receives the test mode signal /TEST in its gate.
The NMOS transistor 30 is arranged between the internal vref line L 4 and the output node of the vref generation circuit 40 . The NMOS transistor 32 is arranged between the pin 1 d (node 2 m ) and the power supply line L 3 . The NMOS transistor 31 is arranged between the pin 1 d (node 2 m ) and the internal vref line L 4 . The vref generation circuit 40 generates a prescribed reference voltage vref in response to the test mode signal TEST.
The voltage of the internal vref line L 4 changes in response to a signal output from the vref generation circuit 40 when the test mode signal TEST goes high, and changes in response to the reference voltage vref received in the pin 1 d when the test mode signal TEST goes low in the normal mode.
When the test mode signal TEST goes high, the voltage of the power supply line L 3 changes in response to the voltage received in the pin 1 d .
Thus, the pin 1 d used in the normal mode can be used as a pin for supplying the power supply voltage without separately providing an input pin for supplying the power supply voltage to the test-system circuit (synchronous circuit). Consequently, a stable power supply voltage can be supplied to the test-system circuit.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | The inventive semiconductor memory device comprises a synchronous circuit formed by a PLL circuit requiring precise operations, an internal circuit group and a VDC circuit. The VDC circuit, a capacitor, a PMOS transistor for a dummy current and an NMOS transistor serving as a high impedance element are arranged for the synchronous circuit. The VDC circuit is arranged for the internal circuit group. The VDC circuit eliminates power supply noise. The PMOS transistor stabilizes the operation of a differential amplifier of the VDC circuit. The capacitor keeps potential difference between a power supply side and a GND side constant. The NMOS transistor stabilizes the voltage on the GND side. | 6 |
BACKGROUND OF THE INVENTION
[0001] This invention relates in general to drilling a wellbore and, in particular, to drilling an intersecting wellbore through a drill string including well casing or liner and a downhole drilling apparatus interconnected therein.
[0002] Without limiting the scope of the invention, its background is described in connection with drilling a wellbore for hydrocarbon production, as an example.
[0003] Heretofore, in this field, a typical drilling operation has involved attaching a drill bit on the lower end of a drill string and rotating the drill bit along with the drill string to create a wellbore through which subsurface formation fluids may be produced. As the drill bit penetrates the various earth strata to form the wellbore, additional joints of drill pipe are coupled to the drill string. During drilling, drilling fluid is circulated through the drill string and the drill bit to force cuttings out of the wellbore to the surface, and to cool the drill bit.
[0004] Periodically as the drilling of the wellbore progresses, the drill bit and drill string are removed from the wellbore and tubular steel casing is inserted into the wellbore to prevent the wall of the wellbore from caving in during subsequent drilling. Typically, after casing is inserted into the wellbore, the annulus between the casing and wellbore is filled with a cement slurry that hardens to support the casing in the wellbore. Thereafter, deeper sections of wellbore with progressively smaller diameters than the previously installed casing may be drilled.
[0005] Once a predetermined depth is reached for each subsequent section of wellbore, the drill bit and drill string are again removed from the wellbore and that section of the wellbore may be cased. Alternatively, however, a liner may be used to case an open section of wellbore instead of a full casing string. The liner, which is a string of connected lengths of tubular steel pipe joints, is lowered through the casing and into the open wellbore. At its upper end, the liner is attached to a setting tool and liner hanger. The liner hanger attaches the liner to the previous casing such that the casing will support the weight of the liner.
[0006] The length of the liner is predetermined such that its lower end will be proximate the bottom of the open wellbore, with its upper end, including the liner hanger, overlapping the lower end of the casing above. As with the casing, after the liner is inserted into the wellbore, the annulus between the liner and the wellbore may be filled with a cement slurry that hardens to support the liner in the wellbore.
[0007] It has been found, however, that in many well drilling operations it is desirable to minimize rig time by utilizing the casing or liner string as the drill string for rotating a drill bit, which may be left in the wellbore upon the completion of drilling a section of the wellbore. As such, this procedure does not require the use of a separate liner or casing upon the withdrawal of the drill bit and drill string as in conventional drilling operations, and thereby reduces the time needed to drill, case and cement a section of wellbore.
[0008] For example, attempts have been made to utilize the casing or liner string as the drill string along with a drill bit that is rotatable relative to the casing or liner string. The drill bit is rotated by a downhole drill motor that is driven by drilling fluid. Upon completion of drilling operations, the motor and the retrievable portions of the drill bit may be removed from the wellbore so that further wellbore operations, such as cementing, may be carried out and further wellbore extending or drilling operations may be conducted. This system, however, requires the use of expensive and sometimes unreliable downhole drill motors and a specially designed drill bit.
[0009] Alternatively, other attempts have been made to utilize the casing or liner string as the drill string using conventional rotary techniques wherein the drill bit is rotated by rotating the entire casing or liner string. This approach, however, requires the use of a drill bit with minimal cutting structure, since a drill out could not be performed through a typical drill bit having a full cutting structure, such as a tricone bit.
[0010] Therefore, a need has arisen for a drill string which may be used as a well casing or liner, which includes a drill bit on its lower end, and which, upon completion of drilling operations, may be retained within the wellbore without the need to retrieve the drill bit or the drill string. A need has also arisen for such a well casing or liner string that may be left in the wellbore along with a drill bit, and which does not require the use of expensive, unreliable or specialty equipment. Further, a need has arisen for such a well casing or liner string which may be cemented in place along with a drill bit having a full cutting structure.
SUMMARY OF THE INVENTION
[0011] The present invention, as exemplified by an embodiment disclosed herein, comprises a downhole drilling apparatus that is interconnectable in a casing or liner drill string and includes a drill bit connected thereto which, upon completion of drilling operations, may be retained within the wellbore without the need to retrieve the drill bit or the drill string. The apparatus allows the well casing or liner to be left in the wellbore along with the drill bit and does not require the use of expensive, unreliable or specialty equipment. The apparatus also allows for the well casing or liner to be cemented in place along with a drill bit having a full cutting structure.
[0012] The downhole drilling apparatus includes a housing that is interconnectable in a casing string. The housing has a window cut therein to allow a subsequent drill bit and pipe string to pass therethrough during a drill out operation. To facilitate the deflection of the drill bit and pipe string through the window, a whipstock is disposed within the housing. A filler material is also disposed within the housing between the whipstock and the window to prevent the flow of drilling fluids or cement through the window prior to the drill out. The filler and the whipstock have a central bore that permits the passage of fluids through the center of the downhole drilling apparatus. One or more valves may be disposed within the central bore to control the flow of fluids therethrough. The valves may be, for example, back pressure or float valves that allow one-way flow of fluids downwardly through the apparatus.
[0013] A drill bit having a full cutting structure, such as a tricone bit, may be operably coupled to the downhole drilling apparatus. The casing or liner string may be used to rotate the drill bit. Alternatively, a downhole motor may be coupled between the downhole drilling apparatus and the drill bit to facilitate rotation of the drill bit, without the need for rotating the casing string.
[0014] In another embodiment, a downhole drilling apparatus includes a housing having a window, an alignment member disposed within the housing and a back pressure valve assembly. The back pressure valve assembly includes a central bore that permits the passage of fluids therethrough. Once downhole, a whipstock may be run into the apparatus such that the whipstock operably engages the alignment member. The alignment member orients the whipstock within the housing relative to the window, so that the drill bit may subsequently be deflected through the window.
[0015] In operation, either embodiment of the downhole drilling apparatus may be interconnected in a casing or liner string having a drill bit disposed on its lower end. A first wellbore is drilled. Following the drilling of the first wellbore, the casing or liner string may be cemented within the wellbore. A pipe string having another drill bit on its lower end is passed through the casing or liner string, such that a drill out through the downhole drilling apparatus is performed to drill a second wellbore. The pipe string and drill bit that are used to create the second wellbore are deflected through the window in the housing of the downhole drilling apparatus by the whipstock disposed within the apparatus.
[0016] Thus, with the use of the downhole drilling apparatus, a casing or liner string including a drill bit having a full cutting structure may be used as a drill string to create a wellbore. The drill string may be cemented in place within the wellbore, and thereafter have a drill out performed therethrough to create an intersecting wellbore.
[0017] These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] For a more complete understanding of the present invention, including its features and advantages, reference is now made to the detailed description of the invention, taken in conjunction with the accompanying drawings of which:
[0019] [0019]FIG. 1 is a schematic illustration of an offshore oil and gas platform during a drilling operating wherein a downhole drilling apparatus embodying principles of the present invention is utilized;
[0020] [0020]FIG. 2 is a schematic illustration of a first downhole drilling apparatus embodying principles of the present invention;
[0021] [0021]FIG. 3 is a cross sectional view of the downhole drilling apparatus of FIG. 2, taken along line 3 - 3 ;
[0022] [0022]FIG. 4 is a cross sectional view of the downhole drilling apparatus of FIG. 2, taken along line 4 - 4 ;
[0023] [0023]FIG. 5 is a schematic illustration of an offshore oil and gas platform during a drilling operating wherein a downhole drilling apparatus embodying principles of the present invention is being utilized in conjunction with a downhole motor;
[0024] [0024]FIG. 6 is a cross sectional view of a second downhole drilling apparatus embodying principles of the present invention before insertion of a whipstock therein; and
[0025] [0025]FIG. 7 is a cross sectional view of the second downhole drilling apparatus after insertion of a whipstock therein.
DETAILED DESCRIPTION
[0026] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention, and do not limit the scope of the invention.
[0027] Referring to FIG. 1, an offshore oil and gas platform is schematically illustrated and generally designated 10 . A semi-submersible platform 12 is centered over a subterranean oil and gas formation 14 located below sea floor 16 . A well 18 extends through the sea 20 , penetrating sea floor 16 to form wellbore 22 , which traverses various earth strata. A wellbore extension is formed by wellbore 24 , which extends from wellbore 22 through additional earth strata, including formation 14 .
[0028] Platform 12 has a hoisting apparatus 26 and a derrick 28 for raising and lowering pipe strings, such as drill string 30 , including drill bit 32 located in wellbore 24 , and casing string 34 , including drill bit 36 , crossover subassembly 38 and downhole drilling apparatus 40 located in wellbore 22 . As used herein, the term “casing string” is used to refer to a tubular string which includes sections of casing or liner.
[0029] As in a typical drilling operation, wellbore 22 is formed by rotating drill bit 36 while adding additional sections of pipe to casing string 34 . When drill bit 36 reaches total depth, however, casing string 34 and drill bit 36 are not retrieved from wellbore 22 . Rather, casing string 34 and drill bit 36 are cemented in place by cement 42 which fills the annular area between casing string 34 and wellbore 22 .
[0030] Cementing casing string 34 and drill bit 36 in place within wellbore 22 is a cost effective alternative to conventional drilling, in that significant rig time is saved by minimizing the number of trips into and out of wellbore 22 . At least one trip out of wellbore 22 and one trip into wellbore 22 are saved by using downhole drilling apparatus 40 . Additionally, the use of downhole drilling apparatus 40 avoids the possibility of collapse of wellbore 22 , particularly in unconsolidated or weakly consolidated formations.
[0031] Alternatively, downhole drilling apparatus 40 may be used in conjunction with conventional drilling operations once a conventional drill string and bit have been tripped out of wellbore 22 . For example, if wellbore 22 has traversed an unconsolidated or weakly consolidated formation and it is likely that a collapse has occurred within wellbore 22 , it may be necessary to reopen that portion of wellbore 22 . In this case, wellbore 22 may be reopened using casing string 34 with downhole drilling apparatus 40 and drill bit 36 .
[0032] Once cementing of wellbore 22 has been completed, wellbore 24 may be drilled. Drill bit 32 creates wellbore 24 by traveling through window 44 of downhole drilling apparatus 40 , as will be more fully discussed with reference to FIGS. 2 - 4 below. As drill bit 32 and drill string 30 continue to form wellbore 24 , formation 14 is traversed. Note that the drill string 30 may include another apparatus 40 , if desired.
[0033] Even though FIG. 1 depicts wellbore 22 as a vertical wellbore, it should be understood by those skilled in the art that wellbore 22 may be vertical, substantially vertical, inclined or even horizontal. It should also be understood by those skilled in the art that wellbore 22 may include multilateral completions wherein wellbore 22 may be the primary wellbore having one or more branch wellbore extending laterally therefrom, or wellbore 22 may be a branch wellbore. Additionally, while FIG. 1 depicts an offshore environment, it should be understood by one skilled in the art that the use of downhole drilling apparatus 40 is equally well suited for operation in an onshore environment.
[0034] Schematically illustrated in FIG. 2 is a downhole drilling apparatus 50 embodying principles of the present invention. Apparatus 50 has a pin end 52 , so that the apparatus 50 is interconnectable in a drill string, such as casing string 34 of FIG. 1. Downhole drilling apparatus 50 also has a box end 54 that may be threadedly connected to crossover subassembly 38 as depicted in FIG. 1.
[0035] Apparatus 50 has a generally tubular housing 56 with a window 58 cut through a sidewall thereof. Window 58 is generally elliptically shaped and is sized such that a drill bit, such as drill bit 32 of FIG. 1, may pass therethrough during a drill out operation.
[0036] Now referring to FIG. 3, a cross sectional view of downhole drilling apparatus 50 taken along line 3 - 3 of FIG. 2 is depicted. Disposed within housing 56 of apparatus 50 is a whipstock 60 . A central bore 62 extends through whipstock 60 to provide fluid passage for drilling mud and cement through apparatus 50 during drilling and cementing operations. Valves 64 , 66 are disposed within central bore 62 of the downhole drilling apparatus 50 . Valves 64 , 66 may be back pressure or float valves that allow one-way flow of drilling mud or cement through the apparatus 50 . As an example, valves 64 , 66 may be SuperSeal II back pressure valves, available from Halliburton Energy Services, Inc. of Duncan, Okla.
[0037] Whipstock 60 has an inclined upper surface, so that it directs a drill bit, such as drill bit 32 of FIG. 1, through window 58 of downhole drilling apparatus 50 . Whipstock 60 may be constructed of any material, such as steel, having sufficient strength to deflect a drill bit through window 58 . Whipstock 60 may also provide additional torsional strength to the downhole drilling apparatus 50 .
[0038] A filler 68 occupies the volume between whipstock 60 and window 58 of downhole drilling apparatus 50 . Filler 68 prevents the flow of drilling mud or cement through window 58 of apparatus 50 . Filler 68 may be, for example, concrete that has been poured into downhole drilling apparatus 50 . Window 58 may also be filled with filler 68 to provide protection to window 58 . Other suitable solid materials, such as resins, may be used for filler 68 , so long as they set sufficiently and permit the directional passage of a drill bit through window 58 of apparatus 50 .
[0039] In operation, when a drill bit, such as drill bit 32 of FIG. 1, encounters whipstock 60 , the drill bit cuts through filler 68 and is deflected laterally by whipstock 60 toward window 58 in housing 56 . Window 58 is wider that the outer diameter of the drill bit, permitting the drill bit to laterally exit the apparatus 50 .
[0040] Referring now to FIG. 4, a cross sectional view of downhole drilling apparatus 50 is depicted that is taken along line 4 - 4 of FIG. 2. Apparatus 50 includes housing 56 , whipstock 60 , filler 68 and window 58 . As with typical drill down shoes, downhole drilling apparatus 50 may have sufficient torsional strength to rotate a drill bit, such as drill bit 36 of FIG. 1. The wall thickness of housing 56 and the size of window 58 will affect the torsional strength of downhole drilling apparatus 50 . Of course, the window 58 should be dimensioned to permit a drill bit to pass therethrough.
[0041] The shape of whipstock 60 can be varied to maximize its deflecting capability. For example, whipstock 60 may be made concave or convex to direct a drill bit, such as drill bit 32 , through window 58 of downhole drilling apparatus 50 . If whipstock 60 is made concave, drill bit 32 will encounter window 58 at a position slightly below that where a straight whipstock 60 would direct the bit. Conversely, a convex whipstock 60 will force the encounter of drill bit 32 with window 58 at a position above that of the flat-surfaced whipstock 60 .
[0042] Referring now to FIG. 5, an offshore oil and gas platform is schematically illustrated and generally designated 70 . A semi-submersible platform 72 is centered over a subterranean oil and gas formation 74 located below sea floor 76 . A well 78 extends through the sea 80 , penetrating sea floor 76 to form wellbore 82 , which traverses various earth strata. Wellbore 82 has a wellbore extension that is formed by wellbore 84 , which extends from wellbore 82 through additional earth strata, including formation 74 .
[0043] Platform 72 has a hoisting apparatus 86 and a derrick 88 for raising and lowering pipe strings, such as drill string 90 , including drill bit 92 located in wellbore 84 , and casing string 94 , including drill bit 96 , to downhole motor 98 , crossover subassembly 100 and downhole drilling apparatus 102 located in wellbore 82 . Using downhole motor 98 , it is not necessary to rotate casing string 94 , including downhole drilling apparatus 102 , in order to rotate drill bit 96 .
[0044] Drilling mud, used to cool drill bit 96 and carry cuttings to the surface, also provides the power to operate downhole motor 98 . As the drilling mud travels through downhole motor 98 , downhole motor 98 imparts rotation to drill bit 96 , so that wellbore 82 is drilled. Using downhole motor 98 in conjunction with downhole drilling apparatus 102 reduces the torsional stress typically encountered by downhole drilling apparatus 102 when casing string 94 is used to rotate drill bit 96 . This reduction in torsional stress allows for the use of a maximum width window 106 in downhole drilling apparatus 102 .
[0045] When drill bit 96 reaches total depth, casing string 94 , including drill bit 96 , downhole motor 98 , crossover subassembly 100 and downhole drilling apparatus 102 , is not retrieved from wellbore 82 . Rather, casing string 94 is cemented in place by cement 104 , which fills the annular area between casing string 94 and wellbore 82 .
[0046] Once cementing of wellbore 82 has been completed, wellbore 84 maybe drilled using downhole drilling apparatus 102 . Drill bit 92 creates wellbore 84 by traveling through window 106 of downhole drilling apparatus 102 in the manner discussed above with reference to FIGS. 2 - 4 .
[0047] Referring next to FIG. 6, a cross sectional view of another downhole drilling apparatus 120 embodying principles of the present invention is depicted. Downhole drilling apparatus 120 has a pin end 122 , so that downhole drilling apparatus 12 is interconnectable in a drill string, such as casing string 94 of FIG. 5, or to other downhole tools. Downhole drilling apparatus 120 also has a box end 123 which may be threadedly connected to crossover subassembly 100 as depicted in FIG. 5.
[0048] Apparatus 120 has a generally tubular housing 124 with a window 126 cut through a sidewall thereof. Window 126 is generally elliptically shaped and is sized such that a drill bit, such as drill bit 92 of FIG. 5, may pass therethrough during a drill out operation. Surrounding window 126 is a cover or shield 128 that prevents the flow of drilling mud or cement through window 126 . Apparatus 120 also has at least one alignment member 130 , such as a track, within housing 124 .
[0049] Disposed within housing 124 is a back pressure valve assembly 132 . A central bore 134 extends through back pressure valve assembly 132 to provide fluid passage for drilling mud and cement used during drilling and cementing operations. Valves 136 , 138 are disposed within central bore 134 of back pressure valve assembly 132 . Valves 136 , 138 may be back pressure valves or float valves that allow one-way flow of drilling mud or cement therethrough.
[0050] As best seen in FIG. 7, a whipstock 140 may be run into downhole drilling apparatus 120 to direct a drill bit, such as drill bit 92 of FIG. 5, through window 126 of apparatus 120 . Whipstock 140 may be installed within downhole drilling apparatus 120 following a cementing operation and subsequent use of a conventional cementing plug 142 . Whipstock 140 includes one or more alignment lugs 144 that cooperate with track 130 of downhole drilling apparatus 120 to radially orient whipstock 140 with respect to window 126 .
[0051] After cementing the casing string 94 within wellbore 82 , including installing the plug 142 in the drilling apparatus 120 , the whipstock 140 is conveyed into the drilling apparatus. The alignment track 130 and lugs 144 cooperatively engage and thereby radially orient the whipstock 140 to face toward the window 126 . A drill bit may then be deflected off of the whipstock 140 to cut through the shield 128 , or the shield may be previously displaced to open the window 126 , for example, by using a conventional shifting tool.
[0052] In the embodiments described above, the present invention provides the ability to drill a wellbore using a well casing or liner string as the drill string, and using a drill bit having a full cutting structure. The use of a downhole drilling apparatus embodying principles of the present invention as part of the drill string allows a well extension to be drilled from the existing wellbore, without having to bore through a drill bit on the end of the casing or liner string. Thus, trips into and out of the wellbore may be eliminated and a drill bit having a full cutting structure may be used.
[0053] While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is, therefore, intended that the appended claims encompass any such modifications or embodiments. | A downhole drilling apparatus for interconnection in a casing or liner string having a drill bit disposed thereon for enabling the drilling of intersecting wellbores without removal of the drill bit is disclosed. In a disclosed embodiment, the apparatus comprises a housing having a window. A whipstock is disposed within the housing. Between the window and the whipstock is a filler. The whipstock and the filler define a central bore providing a fluid path through the apparatus. A back pressure valve may be disposed within the central bore to prevent back flow of fluids through the apparatus. Once the total depth of an initial wellbore is reached, the casing or liner string, including the apparatus, may be cemented in place. Thereafter, an intersecting wellbore may be drilled by laterally deflecting a second drill bit with the whipstock through the window of the housing. | 4 |
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention is directed to polyester polyols derived from bishydroxymethyl tricyclo compounds and caprolactone and polyurethanes made therefrom.
2. Description of the Prior Art
It is known that polyurethanes can be produced by reaction of polyisocyanates and polyols. The polyols for the reaction may be prepared from many materials. For example, the work of Hostettler and Hostettler et al in U.S. Pat. No. 2,933,477 issued Apr. 19, 1960, U.S. Pat. No. 2,962,514, issued Nov. 29, 1960, and U.S. Pat. No. 2,962,455, issued Nov. 29, 1960, teaches that caprolactone may be utilized to form polyols which are then useful in the formation of other materials, such as polyurethanes. However, the Hostettler and Hostettler et al polyols are solids at room temperature and thus must be heated above their melting point in order to be capable of reacting effectively with other materials.
It is known from U.S. Pat. No. 4,319,049, issued Mar. 9, 1982, to Rogier and the references cited therein that various polycyclic compounds are useful in the resin art in the preparation of various thermoplastic and thermosetting resins.
The use of dimethylol tricyclodecane derived from dicyclopentadiene, in the manufacture of polyurethanes is discussed by Asai, Applications of Dicyclopentadiene in the Polymer Industry, Porima Daijesuto, Vol. 30, No. 12 (1978) pp 33-41. The geminal bis(hydroxymethyl) form of these polycyclic compounds is the subject of the aforementioned U.S. Pat. No. 4,319,049 to Rogier.
To the extent that the disclosures of each of the foregoing references are necessary to the understanding of the present invention, they are hereby incorporated by reference.
SUMMARY OF THE INVENTION
The present invention is directed to polyester polyols derived from bishydroxymethyl tricyclo compounds and caprolactone and polyurethanes derived from these polyols. The polyester polyols of the invention may be may be defined by the structural formulae: ##STR1## where m and n are integers ranging from 0 to 20 and may be the same or different, with the proviso that at least one of m and n is not zero. Formula I depicts the polyols derived from bishydroxymethyl tricyclodecane and caprolactone while formula II depicts the polyols derived from bishydroxymethyl tricyclodecene and caprolactone.
Polyurethanes are prepared from the polyester polyols of the invention by reacting one or more of said polyols with at least one polyisocyanate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The bishydroxymethyl tricyclo reactants of the invention are derived from dicyclopentadiene having the structural formula: ##STR2## The bishydroxymethyl tricyclodecane derivative is prepared by hydrogenating the dialdehyde that has been obtained via an oxo-reaction of dicyclopentadiene as follows: ##STR3## Cobalt carbonyl and rhodium oxide are typically used to catalyze the oxo-reaction. The hydroxymethyl groups are attached at the 8 or 9 and 3 or 4 positions on the ring structure corresponding to the points of unsaturation of the dicyclopentadiene starting material.
It is also possible to prepare geminal bishydroxy compounds by employing selective reaction conditions described in detail in U.S. Pat. No. 4,319,049 to Rogier. The reaction sequence to obtain the geminal bishydroxymethyl derivative proceeds as follows: ##STR4## In this reaction sequence, hydroformylation is restricted to the 8 and 9 positions of the dicyclopentadiene ring, thereby producing the geminal bishydroxymethyl tricyclodecane derivatives. These compounds are identified as 8,8(9,9)-bis(hydroxymethyl)tricyclo[5,2,1,0 2 ,6 ]decane. To obtain the unsaturated bishydroxymethyl tricyclodecane derivatives, the final hydrogenation step is omitted.
In forming the polyester polyols of the present invention, both geminal and non-geminal forms of the bishydroxymethyl tricyclo compounds are acceptable reactants. Accordingly, as used hereinafter, the structural formula: ##STR5## is intended to encompass both forms of bishydroxymethyl tricyclodecane, while the formula ##STR6## denotes the unsaturated geminal derivatives 8,8(9,9)bis(hydroxymethyl)tricyclo[5,2,1,0 2 ,6 ]-dec-3-ene.
The caprolactone reactant which has produced successful polyester polyols of the invention is an unsubstituted epsilon caprolactone having the structural formula: ##STR7## although it is possible that other caprolactones, particularly substituted epsilon caprolacetones will produce acceptable polyester polyols for the purposes of the invention. Unsubstituted epsilon-caprolactones are derived from 6-hydroxy-hexanoic acid. Substituted epsilon-caprolactones are prepared by conversion of substituted cyclohexanes obtained from substituted phenols.
The polyester polyols of the invention are prepared by the reaction of a bishydroxymethyl tricyclo compound and caprolactone in a molar ratio of from about 1:1 to 1:20. The polyols so prepared may be represented by the structural formula: ##STR8## where m and n are integers ranging from 0 to 20, with at least one m and n being a non-zero integer. The reaction product will actually be a mixture of polyester polyols of these formulae with the values for m and n being statistically distributed depending upon such factors as the ratio of reactants, the reaction temperature and the relative reactivity of the hydroxyl groups on the bishydroxymethyl tricyclo reactant. In most cases, a statistically normal distribution of molecular weights will be attained, particularly when the ratio of caprolactone to hydroxyl is two or greater.
The reaction of bishydroxymethyl tricyclo compound and caprolactone is preferably conducted at elevated temperature, typically from about 115° to 130° C., and, preferably, in the presence of from about 0.01 to 0.1% by weight based upon the weight of the bishydroxymethyl tricyclo compound of a suitable catalyst such as butyltin tris(2-ethylhexoate).
A principal advantage of the polyols of the invention is that at lower molar ratios (1/8) of bishydroxymethyl tricyclo compound/caprolactone they exist as liquids of relatively low viscosity at room temperature. This characteristic permits the polyols to be transported to reactors and mixed in reactors with polyisocyanates at room temperature. Many other polyol reactants for producing polyurethanes including those derived from caprolactone and bishydroxymethyl tricyclodecane are not liquid at room temperature and so must be transported in heated lines to the reactor or dissolved in a suitable solvent. For example, a polyester polyol formed by reacting two moles of bishydroxymethyl tricyclodecane with one mole of caprolactone, in accordance with the present invenion, having an equivalent weight of 214 exhibits a viscosity of 37 poises at 23° C. In comparison, a polyester polyol formed from two moles of bishydroxymethyl tricyclodecane and one mole dimethyl terephthalate, having an equivalent weight of 273, is a solid at 23° C. and has a viscosity of 2795 poises at 70° C.
When the molar ratio of bishydroxymethyl tricyclo compound to caprolactone is increased, the resulting products are low melting solids. These solids products melt in the range of 34°-42° C. and are also easily melted and mixed with isocyanates with which they demonstrate good compatibility.
The bishydroxymethyl tricyclodecane derivative can also be alkoxylated to reduce its viscosity and the viscosity of the polyester polyol derived therefrom. This, in turn, permits the use of higher ratios of caprolactone to bishydroxymethyl tricyclodecane in forming liquid polyols in accordance with the invention. Generally, alkoxylation is accomplished using ethylene or propylene oxide in a ratio of from 1 to 10 moles alkylene oxide per hydroxyl equivalents.
In preparing polyurethanes according to the invention, the polyester polyol reactant is reacted with polyisocyanates. Suitable polyisocyanates include ethylene diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1, 2-diisocyanate, ethylidene diisocyanate, cyclopentylene-1, 3-diisocyante, the 1,2-, 1,3- and 1,4-cyclohexylene diisocyanates, the 1,3- and 1,4-phenylene diisocyanates, diphenylmethane diisocyanates, polymethyleneisocyanates, the 2,4- and 2,6-toluene diisocyanates, the 1,3- and 1,4-xylylene diisocyanates, bis(4-isocyanatoethyl) carbonate, 1,8-diisocyanate-p-methane, 1-methyl-2, 4-diisocyanatocyclohexane, the chlorophenylene diisocyanates, naphthalene-1,5-diisocyanate triphenylmethane-4,4', triisocyanate, isopropylbenzene-alpha-4-diisocyanate, 5,6-bicyclo[2.2.1] hept-2-ene diisocyanate, 5,6-diisocyanatobutylbicyclo[2.2.1] hept-2-ene and similar polyisocyanates.
Of particular interest in the present invention are trimethylhexamethylene diisocyanate available from VEBA, heptadecyl (C17) diisocyanate, DDI 1410 an aliphatic C-36 diisocyanate available from the Henkel Corporation of Minneapolis, Minn. (generally such diisocyanates having from 12 to 40 carbons in the aliphatic radical may be used in the present invention) and Isonate 143L diisocyanate, a modified diphenylmethane diisocyanate (MDI) available from Upjohn Corp. Further urethane components are isophorone diisocyanate available from VEBA and Desmodur N an aliphatic triisocyanate available from Mobay. Desmodur N is more particularly defined as the reaction product of 3 moles of hexamethylene diisocyanate and water having an isocyanate equivalent weight as later defined of 191. Other adducts or prepolymers of the polyisocyanate include Desmodur L and Mondur CB which are the adducts of toluene diisocyanate. The foregoing materials have an isocyanate equivalent weight of approximately 250.
The amount of the polyisocyanate utilized in forming the urethane compositions of the present invention is expressed on a percentage equivalent weight basis with respect to the hydroxyl functionality of the polyol reactant. Desirably, each hydroxy functional group on the polyol will react on a 1:1 stoichimetric basis with the isocyanate functionality of the polyisocyanate compound. It is quite feasible, however, to form the urethane linkage using from about 70% to 105%, preferably from about 85% to 100%, on a hydroxyl isocyanate equivalent basis of the polyisocyanate to form the urethane product. These equivalent weights of reactants will generate polyurethanes having an NCO index between about 95 to 140 and preferably between about 100 to 115. The determination of the amount of polyisocyanate required for a given polyol is readily made using the aforementioned hydroxyl or isocyanate equivalent weights and is well known to those of skill in the art. Mixtures of polyisocyanates and polyols may also be used in accordance with these parameters.
Crosslinked polyurethanes are obtained whenever the hydroxyl functionality of the polyol reactant is greater than 2.0. Otherwise, thermoplastic polyurethanes are obtained.
To form the urethane reaction product, the polyester polyol and the organic polyisocyanate reactants are mixed together in the proper proportions. When utilized as a coating the compounds are then quickly spread with a knife blade, brush or spray over the surface of the article to be coated. Where molded articles are desired various techniques such as casting, injection molding, reaction injection molding may be employed.
If desired, various urethane catalysts may be employed to promote the reaction. Examples of such urethane catalysts include triethylene diamine, N-ethylmorpholine, dimethyl piperazine, triethylamine, N,N,N',N'-tetramethylbutane 1,3-diamine, dibutyltin dilaurate, stannous octoate, stannous oleate, and stannous tallate, as well as other art recognized urethane catalysts. Typical levels of the urethane catalyst are from about 0.001% to about 5% by weight of the urethane components.
Trimerization catalysts such as diethylene diamine and BF 3 derivatives, can be included in the reaction mixture to convert the polyisocyanates to polyisocyanurates in situ and then to polyurethanes.
One or more additional polyols may be included in the reaction mixture to modify the properties of the resulting polyurethane, principally hardness and elasticity. Short chain polyols act as hard segment contributors to increase elastomer hardness while long chain polyols act as soft segment contributors to enhance the elastic properties of the elastomer. Such modifying polyols including alkyl or cycloalkyl polyols, ester linked polyols, ether linked polyols, ether and ester linked polyols and hydroxy functional acrylic copolymers.
Specific examples of the alkyl and cycloalkyl polyols include 2,5-hexanediol, 1,6-hexanediol, ethylene glycol, glycerol 1,2,6-hexanetriol, pentaerythritol, 1,4-cyclohexane diol, and 1,4-butanediol.
Examples of ester linked saturated polyols include Niax PCP0200 and PCP0240 both available from Union Carbide and having respective molecular weights of approximately 530 and 2000. Both of the foregoing compounds are diols. Niax PCP0300 also available from Union Carbide is a caprolactone-ester triol having an approximate molecular weight of 540. Niax PCP0310 also available from Union Carbide is a caprolactone ester triol having a molecular weight of approximately 900.
The ether linked saturated polyols include compounds such as diethylene glycol and triethylene glycol both available from Fisher. Other ether linked saturated polyols include Teracol 1000 and 2000, available from Dupont. Further ether linked saturated polyols useful in the present invention include the Polymeg Q0650, Q0100, and Q0200 all of which are ether diols available from Quaker having a respective molecular weight of approximately 650, 1000 and 2000. Pluracol P1010 having an approximate molecular weight of 1050 available from Wyandotte is an example of polypropylene oxide ether linked diol useful in the present invention. Similar Wyandotte products useful as saturated polyols in the present invention include Pluracol TP440 and 150 which are propylene oxide ether linked triols having respective molecular weights of approximately 425 and 1560. In similar fashion Pluracol GP3030 is another saturated polyol suitable for the present invention available from Wyandotte. The foregoing material is a glycerine polypropylene ether linked triol having an approximately molecular weight of 2900.
Additional Pluracols useful in the present invention include Plurcol PEP450 which is a pentaerythritol polypropylene oxide ether linked tetrol having a molecular weight of 405 and Pluracol 493 an ether linked tetrol having a molecular weight of approximately 3630.
In addition, polyols having hydroxyl functionalities greater than 2.0 may be included in the reaction mixture as crosslinking agents. Suitable polyols for this purpose are disclosed in U.S. Pat. No. 4,216,344, issued Aug. 15, 1980 to Rogier. Additional materials which may be used as crosslinking agents are found in the application of Rogier, Ser. No. 233,793, filed Feb. 12, 1981.
Numerous other modifying agents may be added to the polyurethanes of the invention to adapt the elastomer to particular uses. Thus, fillers such as carbon blacks, zinc oxide, titanium oxide and the like can be added. Plasticizers and dyes are other examples of suitable modifying agents.
Because many of the hydroxymethyl polyol and polyisocyanate reactants are liquid, additional heating is only required where lower viscosity for efficient mixing is desired. For convenience the reactants may be heated to the temperature of reaction typically from about 0° to about 110° C., preferably from about room temperature, i.e., 22° C. to about 85° C. The system is operated under a high vacuum to degas the reaction mixture for about fifteen minutes. The reaction mixture is then cured for a time period of from about one to twenty-four hours depending upon the curing temperature and the particular polyurethane formed. Optimum curing cycles can be readily determined without undue experimentation by those of skill in the art.
Polyurethanes of the invention may also be prepared as isocyanate terminated pre-polymers by conducting the reaction with a substantial excess of polyisocyanate and not curing the reaction mixture. The pre-polymer provides an intermediate form of the polyurethane which is more convenient to handle than the individual reactants. By mixing the pre-polymers with additional polyol and curing, the pre-polymer is converted to a polyurethane resin.
Pre-polymers are particularly useful in making microcellular foam. The pre-polymer is mixed with polyol and a blowing agent and then poured into a mold which is heated to form microcellular polyurethane foam.
EXAMPLE 1
The polyester polyols of the invention are obtained by reacting caprolactone with bishydroxymethyl tricyclodecane in the presence of heat and an appropriate catalyst. The following example will illustrate the process.
To 255.1 grams (1.3 moles) of bishydroxymethyl tricyclodecane were added 299.6 grams (2.6 moles) of E-caprolactone and the reactants heated to 100° C. with stirring. To the reactants were added 0.62 grams BF 3 etherate and heating at 100° C. for three hours under N 2 was continued. The temperature was reduced to 50° C. and maintained there without stirring for sixty-three hours. The catalyst was neutralized with an excess of anionic ion exchange resin after dissolving in methanol at 60% solids. The product, after removal of the methanol, had the following properties
______________________________________Brookfield Viscosity (72° F.) =33.2 poisesColor (Gardner) =5Hydroxyl equivalent wt. =195.6Acid value =2.5______________________________________
EXAMPLE 2
A preferred method of preparing a polyester polyol in accordance with the invention is as follows: a reaction vessel is charged with 40 grams (0.2 moles) of bishydroxymethyl tricyclodecane and 182 grams (1.6 moles) of caprolactone. These were heated to 120° C. with stirring and then 0.03 grams of butyltin tris(2-ethylhexoate) was added as catalyst. Heating was continued for 8 hours at 120° C. The reaction was stripped of volatiles for 1 hour at 188° C. and 180 microns Hg pressure.
The resulting product had a hydroxyl equivalent weight of 560.5 and a viscosity of 20.6 poise at 25° C. After one month storage this liquid developed a few crystals which melted at 34° C.
Using the method of the above example, other molar ratios were reacted with products having properties as follows:
______________________________________Molar Ratio OH Eq. Wt. Melting Point, °C.______________________________________1/12 711 421/16 873 40______________________________________
EXAMPLE 3
Exemplary of the usage of this fluid, easily handled, polyester polyol is the reaction with diisocyanates to form useful polyurethane products. An elastomer was prepared using a modifying polyether polyol and 9,9(10,10)-bis(hydroxymethyl) octadecanol (hereinafter referred to as C-20 Triol) as a crosslinking agent.
The blend of polyols comprised 49.1 grams (0.25 equivs.) of the bis(hydroxycaproate)ester of bishydroxymethyl tricyclodecane, 46.17 grams (0.143 equivs.) of polyoxytetramethylene glycol of MW-650 (hereinafter referred to as Polymeg 650), and 10.97 grams (0.095 equivs.) of C-20 Triol. This blend was heated to 70° C. under vacuum for 30 minutes to degas the reactants. The reactants were cooled to 30° C. and 73.76 grams (0.50 equivs.) of Isonate 143L (a modified diphenylmethane diisocyanate (MDI) containing a high percentage of MDI and a lesser amount of polycarbodiimide adducts) were added with stirring. This was degassed for four minutes during which time the temperature rose by exothermic heat of reaction from 30° C. to 70° C. The product was quickly transferred to appropriate release-treated molds and cured for twenty hours at 100° C. It was then removed from the molds and aged at 50% relative humidity and 75° F. for seven days. The resulting elastomer had the following properties
______________________________________Shore Durometer Hardness, D =66Tensile strength at break, psi =4335Tensile strength at yield, psi =1500Elongation at break, % =165Split tear strength, PI =466Compression Set, % =61.2Water absorption, 24 hrs, 70° C., % =1.2Tensile strength, psi, and elongation, % =5255/245after 18 hrs in steam at 125° C., (dry)______________________________________
In this elastomer the bis(hydroxycaproate)ester of bishydroxylmethyl tricyclodecane is considered the hard segment contributor and the polyoxytetramethylene glycol is the soft segment contributor and are used in approximately equal quantities. The C-20 Triol is the crosslinker in this cast elastomer to lend greater heat stability to the product.
EXAMPLE 4
To determine whether the hardness of the elastomer could be varied in the normal fashion by adjusting the molecular weight of the polyoxytetramethylene glycol, another elastomer was prepared. The ratio of reactants was:
______________________________________Bishydroxymethyl caprolactone ester of 0.022 equivs., 4.21 gmsbishydroxymethyl tricyclodecanePolyoxytetramethylene glycol, 0.0123 equivs., 6.52 gms.MW=1000C-20 Triol 0.0082 equivs., 0.94 gmsIsonate 143 L 0.043 equivs., 6.33 gms______________________________________
This elastomer was produced in the same manner as that described in Example 2 and cured similarly. The hardness decreased to Shore A=74. Thus increasing the MW of the soft segment contributor effectively reduced the hardness of the elastomer
EXAMPLE 5
Polyurethanes can also be prepared in accordance with the invention from alkoxylated bishydroxymethyl tricyclodecane derivatives of caprolactone as the following example illustrates.
An ethoxylated bishydroxymethyl tricyclodecane was prepared by reacting ethylene oxide with bishydroxymethyl tricyclodecane in a ratio of ethoxy units to equivalent hydroxy of 3.5 to 1. The ethoxylated polyol was then reacted with caprolactone on a 1:1 molar basis. To 80.4 grams (0.32 equiv.) of this compound were added 58.7 grams (0.1824 equiv.) of Polymeg 650 and 14.0 grams of C-20 Triol. All polyols were mixed and degassed as in Example 1, then 91.8 grams (0.64 equiv.) of Isonate 143L were added. This mixture was heated to 60°-70° C. and degassed under vacuum. When the viscosity became obviously higher (about seven and half minutes) it was poured into molds, cured twenty hours at 100° C. and conditioned seven days at 23° C. and 50% relative humidity before testing. The resulting elastomer had the following properties:
______________________________________Shore Durometer Hardness, D =43Tensile strength at break, psi =1925Tensile strength at yield, psi =160Elongation at break, % =260Split tear strength, PI =155Compression Set, % =19Water absorption, 24 hrs, 70° C., % =2.3Tensile strength, psi, and elongation, =2230/400%, after 18 hrs in steam at125° C., (dry)______________________________________
EXAMPLE 6
To demonstrate that useful elastomers can be prepared from unsaturated tricyclo derivatives, the following example was performed.
To 47.31 grams (0.22 equiv.) of the bis(hydroxycaproate) ester of bis(hydroxymethyl) tricyclodecene were added 55.74 grams (0.10 equiv.) of Tercol 1000 (a polyoxytetramethylene glycol of MW=1000) and 12.00 grams (0.10 equiv.) of C-20 Triol. The three polyols were heaed to 60° C. and degassed under vacuum for 30 minutes and cooled before 64.89 grams (0.44 equiv.) of Isonate 143L were added. The exothermic heat of reaction raised the temperature in four minutes to 60° C. while vacuum degassing the reactants. The elastomer was cured twenty hours at 100° C. and conditioned seven days at 23° C. and 50% relative humidity before testing. The resulting elastomer had the following properties:
______________________________________Shore Durometer Hardness, D =43Tensile strength at break, psi =4754Tensile strength at yield, psi =185Elongation at break, % =240Split tear strength, PI =156Compression Set, % =23Water absorption, 24 hrs, 70° C., % =1.4Tensile strength, psi, and elonga- =3440/245tion, %, after 18 hrs in steamat 125° C., (dry)______________________________________
EXAMPLE 7
In a 500 ml round bottom flash, 89.88 g (0.28 eq.) of bishydroxymethyl tricyclodecane/caprolactone (1/4) was heated under vacuum for 11/2 hours at 80° C. After cooling to 25° C., vacuum was released with nitrogen. The degassed polyol was catalyzed with 0.01 wt.% dibutyltin dilaurate. After thorough mixing, 42,37 grams (0.294 eq.) of degassed Isonate 143L was added and vacuum reapplied. After three minutes of vigorous stirring, the exotherm had built to 50° C. Then with viscosity building, vacuum was released. The contents of the flask was poured into molds (1/8"×6"×6") and placed into a press at 10,000 psi and 105° C. After gelation, the elastomer was demolded and cured for a total of 18 hours at 105° C. After storing for 1 week at 72° F. and 50% R. H. the elastomer had the following properties:
______________________________________Shore Durometer Hardness, A =95Tensile strength at break, psi =5540Elongation at break, % =330Set after break, % =0Split tear strength, PI =420Compression set, % =95Water absorption, 24 hrs, =1.470° C., % =Tensile strength, % retained, =68after 18 hrs in H.sub.2 O at 70° C. =68______________________________________
EXAMPLE 8
Using the same procedure as Example 7, 63.8 g (0.115 eq.) of bishydroxymethyl tricyclodecane/caprolactone was blended with 4.16 g (0.092 eq.) of 1,4 butanediol and 33.0 g (0.18 eq.) of a polycaprolactone triol (equivalent wt=181). After catalyzing to 0.0025 wt. % with dibutyltin dilaurate, the polyol blend was reacted with 59 g (0.42 eq.) of Isonate 143L. After 3 minutes, exotherm reached 45° C. The cured elastomer had the following properties:
______________________________________Shore Durometer Hardness, D =61Tensile strength at break, psi =4590Set after break, % =4Elongation at break, % =190Split tear strength, PI =150Compression set, % =32Water absorption, 24 hrs, 70° C., % =1.5Tensile strength, % retained, after =5518 hrs. in H.sub.2 O at 70° C.______________________________________
EXAMPLE 9
Using the same procedure as Example 7, 67.0 grams (0.12 eq.) of bishydroxymethyl tricyclodecane/caprolactone (1/12) was blended with 0.8 grams (0.24 eq.) of 1,4 butanediol. After catalyzing to 0.01 wt. % with dibutyltin dilaurate, the polyol blend was reacted with 54.3 grams (0.38 eq.) of Isonate 143L. After 1 minute, exotherm reached 40° C. The cured elastomer had the following properties:
______________________________________Shore Durometer Hardness, A =90Tensile strength at break, psi =6710Elongation at break, % =310Set after break, % =16Split tear strength, PI =120Compression set, % =63Water absorption, 24 hrs, 70° C., % =1.3Tensile strength, % retained, after =9118 hrs. in H.sub.2 O at 70° C.______________________________________
From the foregoing detailed description and Examples, it should be apparent that the invention encompasses a wide range of compounds. It should also be apparent that while the invention has been described in terms of various preferred embodiments, and exemplified with respect thereto, those of skill in the art will readily appreciate that various modifications, changes, omissions, and substitutions may be made without departing from the spirit of the invention. It is therefore intended that the present invention be limited solely by the scope of the following claims. | Polyester polyols which are the reaction products of bishydroxymethyl tricyclo-decanes/decenes and a caprolactone in various ratios are disclosed. The polyester polyols are useful in forming polyurethane elastomers, foams, coatings and adhesives. | 8 |
TECHNICAL FIELD
This invention relates to woodworking and particularly to the fabrication of arcuate wooden structures such as arched headers for doors and window jambs.
BACKGROUND OF THE INVENTION
Windows and doorways having arched headers have long been popular architectural additions to homes and buildings. Such windows and doorways typically include a wooden jamb that has spaced vertical members joined at their top ends by a curved or arched wooden header. Although the vertical members of such casings are easily fabricated, reliable methods of fabricating high quality arched wooden headers have long evaded woodworking craftsmen. In one method of crafting such headers, elongated wooden blocks are mitered at their ends and secured together end to end to form the general shape of the arch. The curve is then cut with a band saw to form the arched header, which can then be machined if desired and secured to upper ends of the vertical jamb members. Headers fabricated in this traditional way have had several shortcomings. The butt joints between the blocks, for example, tend to separate over time due to changes of temperature and moisture-induced expansion and contraction of the adjacent blocks. Further, such headers generally are not suitable for staining because the skewed relative orientations of the wood grain of adjacent blocks usually is not considered visually attractive. Consequently these headers often are limited to use in door and window frames that are to be painted.
In a more recent method of fabricating arched headers, a plurality of thin wooden boards are stacked with glue applied between adjacent boards to define a laminate. The stacked boards are placed atop a convex form and an elongated metal band is positioned to extend along the top board and overlie the stack. The ends of the band are then drawn toward the ends of the convex form such that the boards are bent by the band toward engagement with the form. The forces applied by the band to the stacked boards are maintained until the adhesive has cured. This method has certain drawbacks. Bending wood strips into an arcuate form with pressure applied downwardly on each end results in having upward pressure applied to the center portion of the strips and little or no pressure applied intermediate the center portion and the ends. As a result, the individual strips are prone to cracking and are subject to a significant amount of surface friction and sliding motion between layers that interferes with proper compression. In addition, the relatively thick adhesive tends to become trapped between individual lamina in excessive amounts due to surface imperfections in the lamina, ripples formed in the laminae during bending or the uneven application of pressure. As a result, the product quality is uneven and the method is unreliable.
Another known method of forming arcuate pieces is a mass production operation in which hydraulic presses are used to form the arches. In this method, arcuate rams are forced into concave forms with the wood lamina trapped and compressed therebetween. This method is capable of producing large quantities of headers, for example, but is unsuitable for custom work in individual structures and necessitates the use of thin highly flexible lamina which detracts from the finished appearance and adds to the cost. Many of the problems inherent in prior art methods using steel bands are also present with the hydraulic press method.
Thus, a need exists in the art for an apparatus and method of forming arcuate structural members that avoids the disadvantages of the prior art while producing pieces of a quality superior to that of pieces produced by prior art methods. It is to the provision of such an apparatus and method that the present invention is primarily directed.
SUMMARY OF THE INVENTION
Briefly described, the present invention comprises a method and apparatus for producing arcuate structural members such as headers for doors and windows. According to the method, wooden boards or the like are formed in a stack with adhesive spread between the boards. The boards are then clamped together at one end adjacent one end of a convex form and a progressive compressive force is applied by a tool from the clamped end of the stack to the other end thereof to clamp the boards together about the convex form. The force applied by the tool to the stacked boards is first applied adjacent the clamped ends of the boards and the force is progressively moved about the convex form so as to gather the boards toward the form progressively. When the tool reaches the other end of the form the boards are firmly pressed together throughout their facing surfaces.
It is, therefore, one of the principal objects of the present invention to facilitate the fabrication of arched structural members by providing an apparatus and method for expediently and reliably shaping such members, utilizing a force that is progressively applied from one end of the structural member to the other so as to shape the structural member progressively.
Another object of the present invention is to provide an apparatus and method for forming arched structural members that use thicker lamina than prior art methods or devices for enhancing the appearance and reducing the cost of the members and which apparatus and method are adjustable for providing members in a plurality of arcuate shapes and sizes.
A further object of the present invention is to provide an apparatus for forming arcuate headers and the like with the apparatus being easy to build, operate and maintain and with the apparatus being durable for providing a long service life.
A still further object of the present invention is to provide a method of forming arched structural members in which the shapes and sizes into which the pieces are to be formed are easily varied by adjusting the apparatus and with the method providing the ability to form the structural member with straight tangential terminal extensions for connection to the upper end portions of window or door jambs.
These and other objects are attained by the present invention which relates to an apparatus and method for forming arcuate structural members such as a laminated wooden arch over a door or window. The apparatus is constructed so as to form arches of various sizes within the limits of standard building materials, and of a plurality of arcuate shapes, from a semicircle to an elliptical shape.
The method of the present invention involves the steps of applying an adhesive between the lamina, clamping one end of the stack of lamina in a straight jawed vice, applying a force against the outer layer of the lamina toward a convex form and translating the force progressively from the clamped end of the lamina toward the free end of the lamina so as to shape the lamina about the convex form progressively. This sequence provides a thin, even coating of adhesive between the layers of material thus facilitating curing and assuring an attractive appearance.
Various additional objects and advantages of the present invention will become apparent from the following description, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the present apparatus for forming arched structural members;
FIG. 2 is a side elevational view of the present apparatus;
FIG. 3 is a partial, perspective view of the clamping band and roller therefor;
FIG. 4 is a perspective view of one of the support means for the stacked laminae;
FIG. 5 is a partial, side elevational view of the support means shown in the preceding Fig.; and
FIGS. 6A-6E illustrate the sequence of production utilizing the present method.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more specifically to the drawings, and to FIG. 1 in particular, numeral 10 designates generally the apparatus for fabricating arcuate structural members. The apparatus is characterizd by a generally rectangular, horizontal main frame member 12 that has an offset configuration and is supported on the floor by downwardly extending feet 14. The offset configuration of the main frame allows overbending of work pieces, for reasons explained more fully hereinbelow. As can be seen in FIGS. 1 and 2, the main frame includes spaced long leg portions 16, spaced short leg portions 18, and a generally central transversely extending hub 20 adjacent to the intersections of the leg portions.
Secured about the hub 20 are the ends of a plurality of spokes 22 that extend radially outwardly from the hub in a fanned arrangement, with the spokes being secured at their opposite ends to an outer rim member 24. The outer rim is arcuate or semicircular in shape and is secured at its lower ends to the main frame as shown. Mounted on the spokes 22 are a plurality of laterally extending support arms 26, one for each spoke. The individual support arms together form a mandrel 28, around which laminae can be shaped. These arms 26 are adjustably secured on the spokes (FIGS. 4 and 5) and include adjustment screws 30 that can be used to adjust the angular orientations of the arms 26 relative to their respective spokes to compensate for the natural flexing of the spokes and arms under clamping pressure. Spring biased pressure pads (not shown) can also be disposed within holes in the arms 26 if desired and arranged to bear against the spokes 22 to help secure the arms in position on their respective spokes. The arms 26 are thus movable radially relative to the hub 20 on the spokes 22 to vary the dimensions of the mandrel according to the desired shape and size of the finished product.
Pivotally mounted on the central hub 20 is a generally U-shaped main arm assembly 40 comprising parallel right and left arm members 42 and 44 respectively, as shown in FIG. 1, and a connecting arm 46. The right and left arms have offset ends that are rotatably attached to the hub 20 with the arms extending generally radially outwardly from the hub past the outer rim 24 to embrace the spokes 22 and arms 26. The arm assembly is designed to pivot or rotate about the central hub 20 and thus travel from one side of the main frame across the top of the rim 24 to the other side of the main frame.
The main arm assembly 40 carries two motor assemblies, a drive motor assembly 48 which is fixed to the right arm member 42, and an auxiliary motor assembly 50 which is adjustably mounted on the left arm member 44. The drive motor assembly 48 includes a motor 52 with a driven gear 54 that engages a chain 56 or similar element disposed about the outer periphery of the rim 24. Spaced idler gears 58 and 60 are disposed on opposite sides of the drive gear and the chain 56 passes beneath the idler gears and around the driven gear to provide sufficient area of contact between the driven gear and chain and to keep the chain taut as the drive motor assembly moves the main arm about the hub 20. The drive motor assembly is also equipped with a holding means such as caliper brake assembly 62 that can be engaged to resist rotational movement of the arm assembly 40 about the hub 20. Conventional power means such as electric or hydraulic power is used to power the drive motor assembly and its brake assembly.
The auxiliary motor assembly 50 (FIG. 3) is configured to wind a flexible preferably stainless steel band 80 about a cylindrical drum 90. Specifically, the motor assembly 50 includes a motor 82 having a drive gear 84 that engages and drives an element such as chain 86. The chain in turn drives a gear 88 and consequently a drum 90, which is attached to the gear 88. As with the drive motor 52, the auxiliary motor 82 also has a holding means, such as a caliper brake assembly 93 that can be engaged to resist rotational movement of the drum 90. Power for the auxiliary motor and brake assemblies is furnished in a conventional manner as with the drive motor.
The use and operation of the motor assemblies can best be explained in describing the operation of the entire apparatus with reference to FIGS. 1, 2 and 6A-6E. Prior to operation, the desired size and shape of the finished arcuate structural member is selected which might, for example, be semicircular or elliptical. The arms 26 are then positioned on their respective spokes to define a mandrel of size and shape corresponding to that of the finished structural members. For this purpose, the spokes 22 can expediently be provided with indicia of measurement to assist the operator in accurately positioning the arms 26. An alternate embodiment contemplates a plurality of mandrels of fixed size and shape that can be easily substituted for each other on the apparatus and that could replace the spoke and arm design of the preferred embodiment.
With the desired mandrel shape and size thus established, the wood laminae 91 are assembled in a stacked configuration with a suitable adhesive applied between the individual lamina. A sheet of plastic to protect the support arms can be placed over the mandrel if desired whereupon one end of the gathered laminae is clamped by a suitable adjustable clamp means 92. The clamp 92 has confronting flat jaw surfaces 92A and 92B between which the lamina are captured and clamped. The clamp 92 can be adjusted as detailed below such that jaw surface 92A is aligned with the tangent of the arch formed by the mandrel 28. In this way, the end portions of the lamina are clamped together to form a straight terminal end portion of the finished structure that extends tangentially from the arched portion thereof. As mentioned above, this straight portion provides for a secure lap-joint type attachment of the arched header to the spaced vertical elements of a door jamb. Clamp 92 is axially adjustable on leg 16 by means of travel screw 94 and its associated adjuster or crank handle 96.
As noted hereinabove, motor assembly 50 is adjustably mounted on arm 44, the motor assembly being secured to an adjustable carriage means 98. Carriage 98 is operatively associated with a travel screw 100 which is secured parallel with arm 44. The carriage position is adjusted axially on arm 44 by loosening its holding screws 120 and then turning crank 122. The carriage can thus be adjusted such that the band 80 is disposed essentially flush with the outermost one of the clamped wood laminae whereupon the holding screws 120 are tightened to secure the carriage and motor assembly 50 in place.
With the ends of the lamina clamped in clamp 92 and the drum assembly properly adjusted on the arm 44, the apparatus is then operated to compress the lamina progressively together against and around the mandrel 28. Specifically, the controls 51 are first appropriately manipulated to engage the calliper brake 93 of the auxiliary motor assembly 50. The brake pressure can be adjusted to provide the desired degree of resistance to rotation of the drum 90 as best illustrated in FIG. 3. With the brake thus set, the motor 52 can be actuated to rotate the main arm assembly 40 about the central hub 20 in a counter-clockwise direction as seen in FIG. 1. As the arm assembly 40 rotates, the steel band 80 is pulled from about the drum 90 causing the drum to rotate against the resistive force of the caliper brake assembly 93. In this way, great tension is imparted to the band as it is progressively wrapped about the mandrel causing the lamina to be compressed tightly together between the mandrel and the band. Further, since the lamina are compressed progressively from one end toward the other in "pinch roller" fashion, individual boards of the laminate, once having engaged adjacent boards, are not required to shift to find their final relative positions.
The progressively applied pressure also ensures that the adhesive is spread evenly between adjacent lamina by progressively squeezing excess glue just ahead of the line of engagement of the lamina as they are pressed together to form a moving "glue front". The result is a tight strong bond that can hardly be detected making the finished structural member appear to be formed of a single unitary piece of wood. The structure can then be finish machined if desired and stained to provide an archway of exceptional precision and aesthetic appeal.
The operation continues, as illustrated in FIGS. 6A-6E, until the laminae are bent around the mandrel into the desired shape whereupon a terminal clamp 124 is tightened against the band, the laminae, and a block member 126, which provides an inner jaw surface for the terminal clamp. As with clamp 92, the inner jaw surface of the terminal clamp 124 is aligned with the tangent of the mandrel arc to provide a straight terminal portion of the finished member for lap-joint attachment to a door jamb. As shown in FIG. 2, the block member 126 is mounted on a carriage means 128, which is axially adjustable on a subframe member 130 by means of travel screw 132 and adjustment crank 134 to align the inner jaw surface with the mandrel arc. The axial adjustment is of course determined by the radius of the structural member being formed.
The circumferential position of the inner jaw surface block 126 relative to the first clamp 92 is adjustable by means of a subframe 130. The subframe 130 is rotatably attached to the central hub 20 and can be rotated thereabout by means of a lever arm 136 that is rotatably secured at one end to the subframe 130 and at its other end to movable bracket 138. Bracket 138 can be longitudinally positioned by means of a travel screw 140 that in turn can be rotated by a crank 142. As the crank is rotated, the responding bracket and lever arm cause the subframe 130 to pivot a few degrees about the central hub 20. The inner jaw surface is thus moved in an arc that is a continuation of the arc of the mandrel 28. Preferably, the jaw surface can be positioned as described within a range of 180 degrees to 190 degrees relative to the position of the clamp 92. This provides the capability to overbend an arcuate structural member by a few degrees to compensate for the natural tendency of the wood to spring back slightly when removed from the apparatus.
The just described procedure can also be reversed if desired or necessary to, for example, add an additional lamina. In reversing the procedure, the caliper brake 93 of the auxiliary motor assembly is released and the brake 62 of the drive motor assembly simultaneously engaged. The motor 82 can then be engaged to rewind a portion of the band 80 about the drum 90 causing the main arm assembly to pivot in a clockwise direction (FIG. 1) against the resistive force of the caliper brake assembly 62. In this way, the band can be removed from about the mandrel just far enough to insert the new lamina while constantly maintaining compressive force on the remaining portion of the lamina. With the new lamina in place, the process is again reversed to continue formation of the member as described.
Thus, as can be easily appreciated, the present invention allows the easy fabrication of arcuate structural members. Since the compression of the lamina is progressive the lamina, once having been stressed is captured and confined between the mandrel and the band such that lamina breakage often encountered with prior art methods is greatly reduced. Relatively thick lamina may therefore be used, eliminating a significant amount of ripping and planing to get easily bendable strips. Where prior art methods commonly require lamina of less than 1/8" thickness the present invention easily forms arcuate members from significantly thicker strips. In addition, the progressive clamping of the laminae by the band 80 squeezes the adhesive along a "front" which ensures even distribution of the adhesive between adjacent lamina. Upon curing of the adhesive, the arcuate member is unclamped and is ready for decorative machining or staining if desired and for installation.
Thus, while an embodiment of an apparatus and method of forming arcuate structural members and modifications thereof has been shown and described in detail herein, various additional changes and modifications may be made without departing from the scope of the present invention. | An apparatus and method for fabricating arcuate structural members is disclosed, the apparatus including a frame structure (12) having a mandrel (26) mounted thereto, the mandrel having a variable radius. A resilient band (80) is provided for compressing the arcuate member against the mandrel. The method involves the steps of placing adhesive between individual lamina 91 and then progressively applying pressure against the laminae while they are in place adjacent the mandrel progressively from one end of the assembled laminae to the opposite end, utilizing the resilient band. | 1 |
TECHNICAL FIELD
[0001] The present invention relates to a laser device, and specifically to a laser control circuit, a control method and a laser ink line device with laser control circuit.
BACKGROUND ART
[0002] The laser ink line device is a regular device in the field of laser devices. As for the control manner for the laser tubes in a laser ink line device, as shown in FIG. 1 , it is regularly applied to provide with a very simple control circuit in which a control signal generator is configured for each laser tube and directly sends square waves or high-low level to control the on-off of laser tubes.
[0003] As the control circuit sends the same control signals to all laser tubes in the above manner, the open/close state of all laser tubes are same and the function is single which can not satisfy with the users needs. Moreover, even more important, the open/close of laser tubes in the same time will cause the peak interference, that is, when the current is larger, the frequency of the peak interference will improve, causing damage for the laser tubes. In additional, as Alkaline dry battery and NI-MH battery provide with the power source for the laser ink line device, a non-continuous large current will discharge, which will shorten the discharge time of batteries.
[0004] In order to overcome the aforementioned limitation, solve the problem in the prior art and improve the user experience for the laser ink line device, the present invention provides a new laser control circuit for controlling laser tubes more flexibly, reducing the working current for laser tubes and avoiding the peak interference.
SUMMARY OF THE INVENTION
[0005] The objective of the present invention is to provide a laser control circuit so as to provide continuously and smoothly working current to the laser ink line device with the laser control circuit and reduce the damages caused by the peak interference.
[0006] The present invention provides a laser control circuit, comprising at least two laser tubes and a control unit controlling the at least two laser tubes respectively; the control unit sends control signals to the at least two laser tubes to control startup/shutdown thereof; the control unit comprises: a main pulse signal generator and a logic control unit; the main pulse signal generator, the logic control unit and the at least two laser tubes are connected successively; the main pulse signal generator sends control signals to the logic control unit; and the logic control unit classifies the control signals into different types of control signals and sends to the at least two laser tubes, causing the at least two laser tubes to present different working conditions.
[0007] Preferably, the logic control unit comprises a NOT gate; the at least two laser tubes includes a first laser tube group and a second laser tube group; an output end of the main pulse signal generator is connected with an input end of the NOT gate and the first laser tube group so as to send a main control signal to the input end of the NOT gate and the first laser tube group; an output end of the NOT gate connected with the second laser tube group is configured for having the main control signal be inverted and having the first and second laser group startup/shutdown alternately.
[0008] Preferably, the control unit further comprises: at least two secondary pulse signal generators and at least two AND gates; each secondary pulse signal generator is connected with a first input end of each AND gate and sends a secondary pulse signal to the AND gate; a second input end of the AND gate is connected with the main pulse signal generator, while an output end of the AND gate is connected with each laser tube of the first laser tube group; the second input end of the AND gate is connected with the output end of NOT gate so that the main pulse signal generator and the secondary pulse signal generator control the startup/shutdown of each laser tube, while an output end of the AND gate is connected with each laser tube of the second laser tube group.
[0009] Preferably, the main pulse signal generator and the secondary pulse signal generator is a Single Chip Microcomputer.
[0010] Preferably, the main control signal and the secondary control signal have a frequency of 10 kHz.
[0011] Preferably, the first and second laser tube group includes one laser tube respectively.
[0012] The present invention further provides a laser ink line device with the laser control circuit
[0013] The present invention further provides a control method for laser tubes, comprising: classifying the laser tubes into a first laser tube group and a second laser tube group; providing with a control unit corresponding to the first and second laser tube group so as to send control signals to the first and second laser tube group respectively; and having the control unit control the first and second laser group to startup/shutdown alternately.
[0014] Preferably, the control unit comprises an AND gate configured for having the first control signal and second control signal be inverted.
[0015] In the above technical solution, the startup/shutdown state of the first and second laser tube group may be alternately, and the working current is controlled above the maximum working current of the laser tube group instead of the superposition in the prior art, so as to reduce the working current, avoid the peak interference and prevent the laser tubes from being damaged. Additionally, a continuously and smoothly current is provided when the laser ink line device works, which may extend discharge time of Alkaline dry battery and NI-MH battery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows the control circuit in the prior art; and
[0017] FIG. 2 shows the control circuit in a preferred embodiment of the present invention.
[0018] 1 main pulse signal generator;
[0019] 2 secondary pulse signal generator.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] The advantages of the present invention will be detailed and described in reference to the drawings and the embodiments as follows.
[0021] As shown in FIG. 2 , in a preferred embodiment of the present invention, a laser control circuit comprises at least two laser tubes and a control unit configured for controlling the at least two laser tubes, so that the control unit may control the startup/shutdown state of the laser tubes through sending control signals to each laser tube. In the present invention, in order to solve the above-mentioned problem, the at least two laser tubes are classified into two group, i.e., a first laser tube and a second laser tube. It is pointed out that the method of classification is not limited, and the user, depending on the actual working requirements, may classify the laser to be a first group and a second group on basis of different displaying status as needed, for example, may define one laser tube as a first laser group and define another one as a second laser group, or classify all laser tubes into the corresponding two. The classification is flexible.
[0022] Furthermore, the control unit further comprises a main pulse signal generator 11 , as same as other controllers contained in the control unit, the main pulse signal generator 11 is configured for sending a control signal to control the status of laser tubes. Moreover, the control unit further comprises a logical control unit provided among the main pulse signal generator 11 , the first and second laser groups to classify the control signals from the main pulse signals into two for being sent to the first and second laser groups separately. After receiving the different control signals, the first laser group will present a startup/shutdown state while the second laser group presents a shutdown/startup state which is contrary to that of the first laser group.
[0023] In a preferred embodiment, the logic control unit is a NOT gate which is connected with the main pulse signal generator 1 , the first and second laser group in a manner of: an output end of the main pulse signal generator 1 is connected with an input end of the NOT gate and the first laser tube, so that the first laser may directly receives the control signals from the main pulse signal generator 1 and determine if startup or shutdown according to the control signals as received; an output end of the NOT gate is connected with the second laser tube group, so that control signals from the main pulse signal generator 1 may be sent to the second laser tube group through the NOT gate, in this circumstances, the control signals received from the second laser group are always inverted to that received from the first laser group, i.e., the working state of the first and second laser group is always contrary to each other.
[0024] In other embodiments, the logic control unit may be a NAND gate (not shown), i.e., both two output ends of the main pulse signal generator 1 are connected with an input end of the NAND gate. In additional, one of the output ends of the main pulse signal generator 1 is directly connected with the first laser group so that the control signals received by the first laser group are the control signals sent from the main pulse signal generator 1 . If the output of the control signal through the NAND gate is a low level while its input is a high level, the first laser group will start and the second laser group will close; if the output is a high level while the input is a low level, the second laser group will startup and the first laser group will shutdown, which causes the two laser groups being inverted.
[0025] Compared with above-mentioned logical control unit which is a NOT gate, the control circuit for a NAND gate is more complicated and requires much more for the circuit, therefore, a NOT gate would be more simply and practical.
[0026] It is understood that the person skilled in the art may obtain the logical control unit defined in the present application through the combination of different logical modules, the above-mentioned embodiment is not a limit to the logical control unit, and any logical control unit having the corresponding effective may be applied in the present application.
[0027] In order to have each laser tube controlled by the external control device, more preferably, the control unit further comprises at least two secondary pulse signal generators 2 and at least two AND gates. The secondary pulse signal generators are corresponding to the main pulse signal generators, specially, one secondary pulse signal generator and one AND gate are corresponding to each laser tube with the following connecting method: each secondary pulse signal generator 2 is connected with a first input end of the AND gate for sending control signals to the AND gate; the connection for a second output of the NOT gate depends on the classification of laser tubes, specially, one second input end of the AND gate connected with the first laser tube group is further connected with the main pulse signal generator 1 , while the other second input end of the AND gate connected with the second laser tube group is connected with the output end of the NOT gate, i.e., the inputs of both two input ends of the AND gate connected with the first laser tube group are secondary controls signals and main control signals respectively, instead, the inputs of both two input ends of the AND gate connected with the second laser tube group are secondary control signals and inverted main control signals respectively. In the meantime, output ends of the AND gate are connected with each laser tube.
[0028] In this circumstance, the laser tubes can determine if startup/shutdown on the basis of if the main control signals are inverted or not only when the input of the secondary pulse signal is a high level. When the external control device is under control and the input of the secondary pulse signal is a low level, the output of the AND gate must be a low level and the laser tubes will not be startup, whenever the input of the second end of the AND gate is a high or low level. Therefore, users may control the startup/shutdown of laser tubers by handing an external control device.
[0029] In a preferred embodiment, the main and secondary pulse signal generator 1 , 2 is a Single Chip Microcomputer (“SCM”) which having the function of adjusting control signals. Compared with a simple timer and other time counters, it may improve the duty ratio of control signals.
[0030] The main control signal and the secondary control signal may be a control signal with frequency of 10 kHz. Users may select different frequency, e.g., 7.8125 kHz, 5 kHz etc. The 10 kHz may improve the anti-interference performance against sunshine when a high laser detects, although the selection of the frequency is determined by the needs of a laser detector.
[0031] In all above-mentioned preferred embodiments, quantity of laser tubers included by first and second laser tube group may be one. As more laser tubers will require more working current superposition, which cause the peak pulse interference when open or close the power source, quantity of laser tubers shall be two, one for the first laser group and the other one for the second laser group, so that the working current will be the maximum current of the two laser tubes. Specially, as the following table shows, the first laser tube contained in the first laser group is defined as I 1 and the first laser tube contained in the first laser group is defined as I 2 .
[0000]
Secondary control signal
1
0
Working current of the prior art
I 1 + I 2
0
Main Control Signal
1
0
1
0
Working current of the present
I 1
I 2
0
0
invention
[0032] In the prior art, the maximum current of a laser ink line device is the sum of two laser tubes, i.e., I 1 +I 2 . In the present application, since the two laser tubes open alternatively, the maximum current will be I 1 when the first laser tube works, and the maximum current will be I 2 when the second laser tube works. Compared with the prior art, the maximum current will reduce 50% than that of the prior art if the working current of the first laser tube I 1 is equal to that of the second laser tube I 2 , the working current will be more smoothly and continuously, reducing the damages caused by the peak interference.
[0033] The present application further discloses a laser ink line device with the laser control circuit as above-mentioned, since the method for connecting the control circuit and an external circuit does not change, the control circuit may be provided in the laser ink line device by the connecting method which is same as that in the prior art, so that the working current would be more smoothly and continuously, and the laser effects would be more variously.
[0034] The present application further discloses a control method of the above laser tube. Firstly, classifying all laser tubes into a first laser tube group and a second laser tube group so as to satisfy with the requirements of presenting various effects; Secondly, providing with a control unit corresponding to the first and second laser tube group so as to send a first and second control signal to the first and second laser tube group respectively. According to the different control signals, the control unit completes the alternately startup/shutdown of the first and second laser group.
[0035] Wherein, as applied in the above preferred embodiments, the control unit includes a logical control unit, preferred is a AND gate, classifying the control signals into original control signals and inverted control signals, the first control signals are the main control signals and the second control signals are the inverted main control signals.
[0036] In the above technical solution, the startup/shutdown state of the first and second laser tube group may be alternately, and the working current is controlled above the maximum working current of the laser tube group instead of the superposition in the prior art, so as to reduce the working current, avoid the interference from peak and prevent the laser tubes from being damaged. Additionally, a continuously and smoothly current is provided when the laser ink line device works, which may extend discharge time of Alkaline dry battery and NI-MH battery.
[0037] It should be noted that the embodiments of the present invention has a preferred implementation, and will not limit the present invention in any form, and any technician skilled in the field may change or modify to equivalent effective embodiments by using the above-described technique. Whenever the contents do not depart from the technical proposal in the present invention, any revision or equivalent change and modification of the above embodiments according to the technical substance of the present invention are all in the scope of the technical proposal in the present invention. | A laser control circuit, comprising at least two laser tubes and a control unit controlling the at least two laser tubes respectively; the control unit sends control signals to the at least two laser tubes to control startup/shutdown thereof. The control unit comprises: a main pulse signal generator and a logic control unit; the main pulse signal generator, the logic control unit and the at least two laser tubes are connected successively; and the logic control unit classifies the control signals into different types of control signals and sends to the at least two laser tubes, causing the at least two laser tubes to present different working conditions. The laser control circuit has more flexible control over the laser tubes, reduces working current of the laser tubes and allows the working current to be steadier, thus avoiding peak interference. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation of co-pending U.S. patent application Ser. No. 11/748,946, filed May 15, 2007, now allowed, which is hereby incorporated herein by reference for all that it discloses.
TECHNICAL FIELD
[0002] This invention relates to electrical connectors in general and more specifically to environmentally-resistant electrical connectors.
BACKGROUND
[0003] Numerous types of electrical connectors exist and have been used for decades to provide a removable electrical connection between various types of electrical components and devices. One type of removable electrical connector is known as a bayonet connector. Bayonet connectors were developed decades ago and are commonly used to innerconnect single conductor cables, typically in low power, low voltage applications, such as those commonly used in truck and automotive electrical systems. However, bayonet connectors may be used in other applications as well.
[0004] A typical bayonet connector assembly may comprise a male terminal and a female terminal that are designed to be engaged and disengaged with one another. Both the male and female terminals are typically electrically and mechanically attached to an electrical conductor (e.g., a wire) by crimping, although they may also be soldered. Both types of terminals (e.g., the male and female terminals) are typically mounted within a housing or connector body that supports the terminals and electrically insulates them from one another and from their surroundings. However, most connector bodies do not seal the terminals from the environment, thereby subjecting the terminals to corrosion and other deleterious effects due to exposure to the surrounding environment. Of course, such environmental exposure is undesirable in applications where the environment contains corrosive agents (e.g., salts), such as, for example, in external automotive and commercial vehicle applications.
[0005] While several types of electrical connectors have been developed in an effort to protect the terminals from exposure to the environment, none are without their problems. For example, while some types of connectors are highly effective from a sealing standpoint, i.e., they are good at protecting the electrical terminals from exposure to the environment, such connectors tend to be expensive to produce or are difficult and/or time-consuming to connect and disconnect in service. Other types of connectors, while being of lower cost and easier to use, often fail to protect the electrical terminals from the deleterious effects of the environment. Still other types of connectors may work well when new, but tend to deteriorate rapidly and may be subject to in-service corrosion, which may lead to erratic performance.
SUMMARY OF THE INVENTION
[0006] An embodiment of an electrical connector includes a terminal body defining at least two openings therein. Electrical terminals positioned in each of the at least two openings defined by the terminal body include respective crimp sections that extend beyond an end of the terminal body. A separator fin attached to the end of the terminal body extends beyond the crimp sections of the electrical terminals and is located between the at least two openings in the terminal body so that the separator fin defines a structure that is closed on an inner side to physically separate the crimp sections of the electrical terminals and open on an outer side so that the crimp sections of the electrical terminals are exposed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Illustrative and presently preferred exemplary embodiments of the invention are shown in the drawings in which:
[0008] FIG. 1 is an exploded perspective view of a mating electrical connector pair according to one embodiment of the invention;
[0009] FIG. 2 is a connector-end view of a male portion of a terminal body;
[0010] FIG. 3 is a cross-sectional view in elevation of the male terminal body taken along the line 3 - 3 of FIG. 2 ;
[0011] FIG. 4 is a partial sectional view of the male terminal body;
[0012] FIG. 5 is a terminal-end view of the male terminal body;
[0013] FIG. 6 is a connector-end view of a female portion of a terminal body;
[0014] FIG. 7 is a cross-sectional view in elevation of the female terminal body taken along the line 7 - 7 of FIG. 6 ;
[0015] FIG. 8 is a terminal-end view of the female terminal body;
[0016] FIG. 9 is an end view of a locking collar;
[0017] FIG. 10 is a cross-sectional view in elevation of the locking collar taken along the line 10 - 10 of FIG. 9 ;
[0018] FIG. 11 is a side view of a male electrical terminal; and
[0019] FIG. 12 is a side view of a female electrical terminal.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] An electrical connector 10 according to one embodiment of the present invention is illustrated in FIG. 1 and may comprise both connector portions of a mating electrical connector pair 12 . More specifically, a first electrical connector 10 of the mating electrical connector pair 12 may comprise a male portion 14 , whereas a second electrical connector of the mating electrical connector pair 12 may comprise a female portion 16 . The electrical connector 10 , i.e., either the male portion 14 or the female portion 16 , may comprise a terminal body (e.g., 18 , 18 ′) that defines at least one opening (e.g., 20 , 20 ′) therein sized to receive an electrical terminal (e.g., 22 , 22 ′).
[0021] Referring now primarily to FIGS. 3 and 7 , each opening 20 , 20 ′ defined by the terminal body 18 , 18 ′ may be provided with a plurality of alignment ribs 24 , 24 ′. As will be described in further detail below, the alignment ribs 24 , 24 ′ help to align the electrical terminals 22 , 22 ′ within the openings 20 , 20 ′ defined by the terminal bodies 18 , 18 ′. The improved terminal alignment provided by the alignment ribs 24 , 24 ′ enhances the engagement of the two electrical connectors 10 , i.e., the male portion 14 and the female portion 16 , that comprise the mating electrical connector pair 12 .
[0022] As will be described in further detail below, each terminal body 18 , 18 ′ may also be provided with additional features and elements that may be used to enhance or achieve the various objects and advantages described herein. For example, each opening 20 , 20 ′ in the terminal body 18 , 18 ′ may also be provided with a tapered portion 26 , 26 ′ comprising a wide end 48 , 48 ′ and a narrow end 50 , 50 ′. The tapered portion 26 , 26 ′ is sized so that it receives a corresponding tapered section 74 , 74 ′ ( FIGS. 11 and 12 ) provided on the electrical terminal 22 , 22 ′ when the terminal 22 , 22 ′ is positioned in the opening 20 , 20 ′. Tapered portion 26 , 26 ′ also helps to center the electrical terminal 22 , 22 ′ within the opening 20 , 20 ′. The openings 20 , 20 ′ may also be provided with a shoulder 28 , 28 ′ sized to engage a tang 30 , 30 ′ ( FIGS. 11 and 12 ) that may be provided on the electrical terminals 22 , 22 ′.
[0023] Each terminal body 18 , 18 ′ may also be provided with one or more separator fins 32 , 32 ′, as best seen in FIG. 1 . The separator fins 32 , 32 ′ prevent the electrical terminals 22 , 22 ′ from contacting one another when in terminal body 18 , 18 ′, thereby preventing an electrical short circuit from developing between the electrical terminals 22 , 22 ′.
[0024] In one embodiment, the mating electrical connector pair 12 , which may comprise two electrical connectors 10 (i.e., the male portion 14 and the female portion 16 ), may be provided with a locking collar 34 . As will be described in further detail below, one or more locking tabs 46 ( FIGS. 9 and 10 ) provided on locking collar 34 are sized to engage one or more grooved portions 36 provided on the mating electrical connector 10 (e.g., the male portion 14 ), thereby securely locking together the two connector portions 14 and 16 of mating electrical connector pair 12 . In addition, each terminal body 18 , 18 ′ may be covered or encapsulated (e.g., by an overmolding process described in greater detail below) by a sleeve 38 , 38 ′, as best seen in FIGS. 3 and 7 . As will be described in greater detail below, the provision of an overmolded sleeve 38 , 38 ′ helps to provide a good physical bond and a gas- and liquid-tight seal between sleeve 38 , 38 ′ and terminal body 18 , 18 ′.
[0025] Referring now to FIGS. 11 and 12 , in one embodiment, the electrical terminals 22 , 22 ′ may comprise plug and socket terminals having a configuration that is similar to that of conventional plug and socket connectors. However, unlike conventional connectors, the plug and socket electrical terminals 22 , 22 ′ that may be utilized in one embodiment of the present invention are provided with a tab portion 40 , 40 ′ that substantially closes a proximal end 42 , 42 ′ of the electrical terminal 22 , 22 ′. The tab portion 40 , 40 ′ prevents the material from migrating into the hollow portion of the electrical terminal 22 , 22 ′, such as, for example, molten sleeve material during the sleeve overmolding process.
[0026] One significant feature of the electrical connector 10 of the present invention is that the alignment ribs 24 , 24 ′ provided in the openings 20 , 20 ′ defined by the terminal bodies 18 , 18 ′ help to properly align the electrical terminals 22 , 22 ′ within the terminal bodies 18 , 18 ′, thereby making it easier to engage the two portions (e.g., the male and female portions 14 and 16 ) of the electrical connectors 10 comprising the mating electrical connector pair 12 . The enhanced alignment of the electrical terminals 22 , 22 ′ provided by the alignment ribs 24 , 24 ′ is particularly advantageous in multiple-terminal configurations, i.e., where the electrical connector 10 comprises a plurality of individual electrical terminals 22 , 22 ′.
[0027] Still other advantages are associated with the various configurations and elements comprising the claimed invention. For example, the tapered portions 26 , 26 ′ provided in the openings 20 , 20 ′ enhance the alignment of the electrical terminals 22 , 22 ′ when they are inserted into the terminal body 18 , 18 ′ during the assembly process. That is, the tapered portions 26 , 26 ′ provide a generous “lead-in” for the terminals 22 , 22 ′. In addition, the tapered portions 26 , 26 ′ provide for improved alignment of the electrical terminals 22 , 22 ′ when they are fully inserted into the terminal bodies 18 , 18 ′. The cooperative engagement of the tangs 30 , 30 ′ provided on the electrical terminals 22 , 22 ′ with the shoulders 28 , 28 ′ provided in the terminal body 18 , 18 ′ helps to positively retain the electrical terminals 22 , 22 ′ within the terminal body 18 , 18 ′, helping to prevent the electrical terminals 22 , 22 ′ from becoming dislodged during subsequent connector use. Moreover, the separator fins 32 , 32 ′ provided on the terminal body 18 , 18 ′ prevent the various electrical terminals 22 , 22 ′ from contacting one another, thereby preventing electrical short circuits from developing between the electrical terminals 22 , 22 ′ contained in the terminal bodies 18 , 18 ′.
[0028] As already briefly described, the mating electrical connector pair 12 may also be provided with a locking collar or ring 34 . In one embodiment, the locking collar 34 may be used to draw together the two portions (e.g., 14 and 16 ) of the mating connector pair 12 to ensure a secure connection and a tight seal between the male and female portions 14 and 16 , particularly where a gasket 44 ( FIG. 1 ) is positioned between the two connector portions 14 and 16 . In addition, the locking collar 34 covers the joint or interface between the electrical terminals 22 , 22 ′ of the two connector portions 14 and 16 , thereby further reducing the likelihood that environmental contaminants will find their way into the interface between the two connector portions 14 and 16 .
[0029] Having briefly described one embodiment of the electrical connector 10 , how it may comprise a portion of a mating electrical connector pair 12 , as well as some of its more significant features and advantages, various embodiments and variations of the present invention will now be described in detail.
[0030] However, before proceeding with the detailed description, it should be noted that while the present invention is shown and described herein as it could be used in conjunction with the plug and socket type of electrical terminals, it could be utilized with other types of electrical terminals, either now known in the art or that may be developed in the future, as would become apparent to persons having ordinary skill in the art after having become familiar with the teachings provided herein. Consequently, the present invention should not be regarded as limited to the particular type of electrical terminals shown and described herein.
[0031] In addition, while the electrical connector shown and described herein comprises seven (7) separate mating electrical terminal pairs 22 , 22 ′, any number of electrical terminal pairs could be used, again as would become apparent to persons having ordinary skill in the art after having become familiar with the teachings provided herein. Consequently, the present invention should not be regarded as limited to the particular configurations and applications shown and described herein.
[0032] Referring back now to FIG. 1 , one embodiment of an electrical connector 10 is shown and described herein as it could be used in conjunction with the so-called plug and socket type of electrical terminals 22 , 22 ′. More specifically, the plug and socket type of electrical terminals may comprise two mating portions: A male terminal 22 and a female terminal 22 ′. See also FIGS. 11 and 12 . As described herein, the electrical connector 10 that receives the male electrical terminal 22 may be referred to herein as the male portion 14 , whereas the electrical connector 10 that receives the female electrical terminal 22 ′ may be referred to herein as the female portion 16 . Both the male portion 14 and the female portion 16 may be referred to herein in the alternative as simply “electrical connector 10 .” Because the male portion 14 is designed to mate with the female portion 16 , the combination of the male and female portions 14 and 16 also may be referred to herein as the mating electrical connector pair 12 .
[0033] Referring now primarily to FIGS. 2-5 , the male portion 14 of the electrical connector may comprise a terminal body 18 that defines at least one opening 20 therein sized to receive electrical terminal 22 . The terminal body 18 may be configured to provide electrical connections for any number of electrical terminals 22 . By way of example, in the embodiment shown and described herein, the terminal body 18 defines seven (7) openings 20 , thereby allowing the electrical connector 10 to provide seven (7) discrete electrical connections. Alternatively, of course, a greater or fewer number of openings 20 may be provided, depending on the desired number of electrical connections to be provided. Consequently, the present invention should not be regarded as limited to a terminal body 18 defining any particular number of openings 20 .
[0034] Each opening 20 in terminal body 18 may be provided with a plurality of alignment ribs 24 sized and positioned so that they will position the electrical terminal 22 at the desired location (e.g., concentrically) within the opening 20 . In the embodiment shown and described herein four (4) alignment ribs 24 are provided at substantially diametrically opposed locations within the opening 20 , as best seen in FIG. 2 . Alternatively, a greater or fewer number of alignment ribs 24 may be used and may be located at different positions depending on the number of alignment ribs 24 to be provided. For example, in another embodiment (not shown), three (3) separate alignment ribs 24 may be provided. However, instead of being diametrically opposed, the three (3) separate alignment ribs 24 may be spaced substantially evenly around the opening 20 (e.g., at 120° intervals).
[0035] Each opening 20 may also be provided with a tapered section 26 ( FIG. 3 ). Tapered section 26 may comprise a wide end 48 and a narrow end 50 . Electrical terminal 22 may be provided with a corresponding tapered section 74 , as best seen in FIG. 11 . Thus, when the electrical terminal 22 is inserted into the terminal body 18 , the wide end 48 of tapered section 26 will serve as a lead-in for the distal end 52 ( FIG. 11 ) of electrical terminal 22 . When the electrical terminal 22 is fully inserted into terminal body 18 , the narrow end 50 will contact the electrical terminal 22 , thereby helping to properly locate the electrical terminal 22 within terminal body 18 .
[0036] Each opening 20 may also be provided with a shoulder 28 sized to engage a tang 30 ( FIG. 11 ) provided on the electrical terminal 22 . More specifically, shoulder 28 will engage tang 30 when the electrical terminal 22 is fully inserted into terminal body 18 . The engagement of shoulder 28 and tang 30 will also prevent the electrical terminal 22 from being pushed back out from terminal body 18 during service.
[0037] Terminal body 18 may also be provided with one or more separator fins 32 that extend generally rearwardly from terminal body 18 , as best seen in FIGS. 1 and 3 - 5 . The separator fins 32 may be generally co-extensive with the electrical terminals 22 when they are fully inserted into the terminal body 18 , so as to prevent the electrical terminals 22 from contacting one another.
[0038] The separator fins 32 are arranged so that they are located generally between adjacent ones of the openings 20 defined in terminal body 18 , as best seen in FIGS. 1 and 5 . In the embodiment shown and described herein wherein the terminal body 18 is provided with seven (7) openings 20 , the separator fins 32 are arranged so that they define a central opening 33 that is substantially aligned (e.g., concentric with) with the center opening 20 . See FIG. 5 .
[0039] Terminal body 18 may also be provided with other features to provide the electrical connector 10 with additional advantages. For example, in one embodiment, the terminal body 18 and separator fins 32 are provided with notched sections 54 to provide a more secure attachment to the sleeve 38 , as best seen in FIGS. 3 and 4 . The terminal body 18 may also be provided with a recessed face portion 56 . Recessed face portion 56 causes the seam or interface between the two connector portions 14 and 16 to be located within the recessed face portion 56 of the mating electrical connector pair 12 , thereby reducing the likelihood that interface between the two portions 14 and 16 will be exposed to environmental contaminants. In addition, the recessed face portion 56 provides a convenient location for gasket 44 ( FIG. 1 ) if such a gasket is desired.
[0040] Recessed face portion 56 may be provided with an index feature, such as a V-shaped projection 58 ( FIGS. 2 and 3 ) sized to receive a corresponding V-shaped notch 64 ( FIGS. 6 and 7 ) which may be provided in the mating electrical connector 10 (e.g., female portion 16 ). The index feature provides a convenient way to align the connectors to ensure proper connection of the electrical terminals 22 , 22 ′.
[0041] Terminal body 18 of electrical connector 10 may also be provided with one or more grooves or grooved sections 36 sized to engage a locking collar 34 that may be provided on the mating terminal body. See FIGS. 1-4 . In the embodiment shown and described herein, three (3) separate grooved sections 36 are provided around the exterior or outer periphery of terminal body 18 at 120° intervals, as best seen in FIGS. 1 and 2 . Alternatively, a greater or fewer number of grooved sections 36 may be used and may be provided at different spacings or intervals. The grooved sections 36 are sized to receive corresponding locking tabs 46 ( FIG. 9 ) provided on locking collar 34 . In addition, one or more of the grooved sections 36 may be provided with a detent 60 ( FIG. 4 ) configured to engage the locking tabs 46 provided on locking collar 34 . The engagement of the locking tabs 46 with the detents 60 provides a positive locking action for the locking collar 34 . That is, the detents 60 help to secure the locking collar 34 in the fully engaged or locked position.
[0042] The terminal body 18 and the various features and components thereof may be fabricated from any of a wide range of materials, such as plastics or other non-conductive materials, that would be suitable for the intended application. Consequently, the present invention should not be regarded as limited to a terminal body 18 fabricated from any particular type of material. However, by way of example, in one embodiment, the terminal body 18 is molded as a single, unitary piece from nylon “66.”
[0043] Referring now primarily to FIGS. 6-8 , a female portion 16 of an electrical connector 10 may be designed to engage or mate with the male portion 14 of the electrical connector just described. The female portion 16 may comprise a terminal body 18 ′ that defines one or more openings 20 ′ therein. The numbers, sizes, and spacings of the openings 20 ′ may be configured to correspond to the numbers, sizes, and spacings of the openings 20 provided in the terminal body 18 for the male portion 14 of electrical connector 10 . For example, in the embodiment shown and described herein, the terminal body 18 ′ defines seven (7) openings 20 ′ therein in the manner illustrated in FIGS. 1 and 6 - 8 .
[0044] Each opening 20 ′ may be provided with features similar to those provided in openings 20 of terminal body 18 . For example, and with reference now to FIG. 7 , each opening 20 ′ may be provided with a plurality of alignment ribs 24 ′. Alignment ribs 24 ′ may be substantially identical to the alignment ribs 24 , thus will not be described in further detail herein.
[0045] Each opening 20 ′ may also be provided with a tapered section 26 ′ having a wide end 48 ′ and a narrow end 50 ′ that are sized to receive a tapered section 74 ′ ( FIG. 12 ) provided on the mating (e.g., female) electrical terminal 22 ′ in a manner similar to that already described for the tapered section 26 . Opening 20 ′ may also be provided with a shoulder 28 ′ sized to engage a tang 30 ′ provided on female electrical terminal 22 ′.
[0046] As was the case for the male portion 14 of the electrical connector 10 , the terminal body 18 ′ of female portion 16 of electrical connector 10 may be provided with one or more separator fins 32 ′. The separator fins 32 ′ may extend generally rearwardly from the terminal body 18 ′ so that the are co-extensive with the electrical terminals 22 ′ when the electrical terminals 22 ′ are fully inserted in terminal body 18 ′. In the embodiment shown and described herein wherein the terminal body 18 ′ is configured with seven (7) openings 20 ′, the separator fins 32 ′ are arranged so that they define a central opening 33 ′ that is substantially aligned with the opening 20 ′ provided at or near the center of the terminal body 18 ′. See FIGS. 1 and 8 .
[0047] With reference now primarily to FIG. 7 , the terminal body 18 ′ and separator fins 32 ′ may be provided with notched areas or sections 54 ′ to provide a more secure attachment for sleeve 38 ′. Terminal body 18 ′ may also be provided with a raised or extended face section 62 that is sized to be received by the recessed face portion 56 of terminal body 18 , as best seen in FIG. 1 . The raised face section 62 and recessed face 56 may be configured to interface with gasket 44 , as best seen in FIG. 1 . In addition, the raised face section 62 may be provided with an index feature, such as a V-shaped notch 64 ( FIG. 6 ) that is sized to mate with or engage the corresponding index feature (e.g., the V-shaped projection 58 ) provided on the mating terminal body 18 .
[0048] Terminal body 18 ′ may also be provided with a raised shoulder or boss 66 that engages with a similar shoulder 68 provided on locking collar 34 . The engagement of the two shoulders 66 and 68 allows the locking collar 34 to securely hold together the two connector portions 14 and 16 when they are engaged with one another and when the locking collar 34 is rotated to the locked position.
[0049] Terminal body 18 ′ may be fabricated from any of a wide range of materials, such as plastics or other non-conductive materials, that would be suitable for the intended application. Consequently, the present invention should not be regarded as limited to any particular type of material. However, by way of example, in one embodiment, terminal body 18 ′ is molded as a single, unitary piece from nylon “66.”
[0050] As already discussed herein, it may be generally desirable to provide each terminal body 18 , 18 ′ with a sleeve 38 , 38 ′. Sleeves 38 , 38 ′ may provide a good physical bond as well as a gas- and liquid-tight seal with the terminal bodies 18 , 18 ′ and wires 70 , 70 ′ thereby providing for enhanced protection against environmental encroachment. In addition, sleeves 38 , 38 ′ may be configured or shaped to provide an enhanced gripping area for a user. While the sleeves 38 , 38 ′ may comprise a separate component or element that is fitted over the terminal bodies 18 , 18 ′, in many applications it will be generally desirable to form or mold the sleeves 38 , 38 ′ directly on the terminal bodies 18 , 18 ′ after the terminal bodies 18 , 18 ′ have been assembled, i.e., after the various electrical terminals 22 , 22 ′ have been inserted into the openings 20 , 20 ′ provided in terminal bodies 18 , 18 ′.
[0051] In one embodiment, the sleeves 38 , 38 ′ are formed over the terminal bodies 18 , 18 ′ by an “overmolding” process of the type known in the art. So forming the sleeves 38 , 38 ′ by such an overmolding process allows a robust seal (e.g., a gas- and liquid-tight seal) to be established between the terminal bodies 18 , 18 ′, the electrical conductors or wires 70 , 70 ′, and the sleeves 38 , 38 ′.
[0052] More specifically, after the terminal bodies 18 , 18 ′ have been assembled, they may be positioned in a form or mold (not shown) suitable for defining or forming the sleeves 38 , 38 ′. Material (e.g., molten material) that will comprise the sleeves 38 , 38 ′ may then be injected under pressure into the form or mold. During the molding process, the injected material will flow around the various components of the assembled terminal bodies 18 , 18 ′, substantially encapsulating portions of the terminal bodies 18 , 18 ′, portions of the electrical conductors (i.e., wires) 70 , 70 ′, and portions of the electrical terminals 22 , 22 ′, such as, for example, the crimp sections 76 , 76 ′ thereof, as best seen in FIGS. 3 and 4 . Significantly, the closed proximal ends 42 , 42 ′ of electrical terminals 22 , 22 ′ (e.g., formed by the respective tab portions 40 , 40 ′ thereof), prevent molten sleeve material from flowing or migrating into the hollow portions of the electrical terminals 22 , 22 ′ during the molding process. In addition, the engagement of the tapered sections 74 , 74 ′ of the electrical terminals 22 , 22 ′ with the corresponding tapered portions 26 , 26 ′ of terminal bodies 18 , 18 ′ also prevents molten sleeve material from flowing or migrating beyond the narrow ends 50 , 50 ′ to tapered portions 26 , 26 ′ during the molding process.
[0053] Sleeves 38 , 38 ′ may be fabricated from any of a wide range of materials (e.g., plastics) suitable for the particular application and for the particular process (e.g., overmolding) used to form the sleeves 38 , 38 ′. Consequently, the present invention should not be regarded as limited to sleeves 38 , 38 ′ formed from any particular type of material. However, by way of example, in one embodiment, sleeves 38 and 38 ′ are formed from a PVC (polyvinylchloride) plastic material.
[0054] Turning now to FIGS. 1 , 9 , and 10 , locking collar 34 may be used to securely hold together the male and female portions 14 and 16 of the mating electrical connector pair 12 . In the embodiment shown and described herein, locking collar 34 may comprise a generally hollow, cylindrically shaped member having one or more locking tabs 46 provided thereon. Locking collar 34 may also be provided with a shoulder section 68 sized to engage a similar shoulder or boss 66 provided on terminal body 18 ′, as already described. Once the male and female portions 14 and 16 are fully mated together, locking collar 34 may be rotated as necessary to align the locking tabs 46 with the with the grooves 36 provided on the mating terminal body (e.g., terminal body 18 ). Locking collar 34 is then moved axially toward the mating terminal body 18 until the locking tabs 46 engage the inclined sections 72 ( FIG. 4 ) of grooves 36 . Locking collar 34 is then rotated. The engagement of the locking tabs 46 with the inclined sections 72 of grooves 36 causes the two connector portions 14 and 16 to be drawn together as the locking collar is rotated toward the locked position. When rotated to the locked position, the connector portions 14 and 16 will be fully drawn together and the locking tabs 46 will engage the detents 60 provided on grooves 36 , thereby holding the locking collar 34 in the locked position.
[0055] Locking collar 34 may be fabricated from any of a wide range of materials, such as metals or plastics, suitable for the intended application. By way of example, in one embodiment, locking collar 34 is fabricated from nylon “66,” although other materials could be used as well.
[0056] The electrical terminals 22 , 22 ′ that may be utilized in one embodiment of the invention are best seen in FIGS. 1 , 11 , and 12 . In one embodiment, the electrical terminals 22 , 22 ′ may comprise a size and configuration that is consistent with the connector standard that is well-known in the art. Alternatively, other types of electrical terminals, either now known in the art or that may be developed in the future, may be used. Referring now primarily to FIG. 11 , a male-type electrical terminal 22 may comprise a generally elongate, hollow structure having a proximal end 42 and a distal end 52 . The proximal end 42 of male electrical terminal 22 may be provided with a tapered section 74 sized to be received by the tapered portion 26 provided in the opening 20 of terminal body 18 ( FIG. 3 ) in the manner already described. Electrical terminal 22 may also be provided with a tang 30 sized and positioned to engage the shoulder 28 provided in the opening 20 of terminal body 18 . Proximal end 42 of male electrical terminal 22 may also be provided with a suitable crimp section 76 for allowing the electrical conductor of a wire 70 ( FIG. 1 ) to be crimped (i.e., connected) to the electrical terminal 22 .
[0057] The proximal end 42 of male electrical terminal 22 is also provided with a tab 40 that substantially closes the proximal end 42 of the electrical terminal 22 . The tab 40 prevents unwanted material from migrating into the hollow portion of the electrical terminal 22 , thereby enhancing the reliability and durability of the electrical connector. The presence of the tab 40 is particularly beneficial in situations wherein the sleeve 38 is formed by the overmolding process already described. That is, tab 40 prevents molten sleeve material from migrating into the hollow portion of the electrical terminal 22 .
[0058] A female type of electrical terminal 22 ′ is best seen in FIGS. 1 and 12 and may comprise a generally elongate, hollow structure having a proximal end 42 ′ and a distal end 52 ′. The proximal end 42 ′ of female electrical terminal 22 ′ may be provided with a tapered section 74 ′ sized to be received by the tapered portion 26 ′ provided in the opening 20 ′ of terminal body 18 ′ ( FIG. 7 ). Electrical terminal 22 ′ may also be provided with a tang 30 ′ sized and positioned to engage the shoulder 28 ′ provided in the opening 20 ′ of terminal body 18 ′. Proximal end 42 ′ of female electrical terminal 22 ′ may also be provided with a suitable crimp section 76 ′ for allowing the electrical conductor of a wire 70 ′ ( FIG. 1 ) to be connected to the electrical terminal 22 ′.
[0059] The proximal end 42 ′ of female electrical terminal 22 ′ is also provided with a tab 40 ′ that substantially closes the proximal end 42 ′ of the electrical terminal 22 ′. The tab portion 40 ′ prevents unwanted material from migrating into the hollow portion of the electrical terminal 22 ′, thereby enhancing the durability and reliability of the electrical connector. The presence of the tab 40 ′ is particularly beneficial in situations wherein the sleeve 38 ′ is formed by the overmolding process already described. That is, tab 40 ′ prevents molten sleeve material from migrating into the hollow portion of the electrical terminal 22 ′.
[0060] The male and female electrical terminals 22 and 22 ′ may be fabricated from any of a wide range of electrically conductive materials and in accordance with any of a wide range of fabrication processes, as would become apparent to persons having ordinary skill in the art after having become familiar with the teachings provided herein. However, by way of example, in one embodiment, each electrical terminal 22 , 22 ′ may be fabricated from a generally flat sheet of material (e.g., metal) that includes features and elements that, when elastically deformed or bent, will form the generally elongate hollow terminal having the desired configuration. In addition, the sheet of material may comprise a tab portion (e.g., 40 , 40 ′) that can be bent or elastically deformed so as to substantially close the proximal end of the electrical terminal 22 , 22 ′ in the manner already described and best seen in FIGS. 11 and 12 .
[0061] Having herein set forth preferred embodiments of the present invention, it is anticipated that suitable modifications can be made thereto which will nonetheless remain within the scope of the invention. The invention shall therefore only be construed in accordance with the following claims: | An electrical connector includes a terminal body defining at least two openings therein. Electrical terminals positioned in each of the at least two openings defined by the terminal body include respective crimp sections that extend beyond an end of the terminal body. A separator fin attached to the end of the terminal body extends beyond the crimp sections of the electrical terminals and is located between the at least two openings in the terminal body so that the separator fin defines a structure that is closed on an inner side to physically separate the crimp sections of the electrical terminals and open on an outer side so that the crimp sections of the electrical terminals are exposed. | 8 |
FIELD OF THE INVENTION
This invention relates to the field of pulp washing technology. Objects of the invention are a method of washing pulp by means of a gradually diluted wash filtrate recovered at an earlier stage of the washing, and a plant for carrying out the method.
BACKGROUND ART
The washing of pulp—the removal of dissolved, undesired components from the pulp following various delignification stages—is still one of the most difficult operations even in the field of the most recent pulping technology, calling for continuous development of equipment and improvement of methods within the washing processes throughout the fibre line.
There are many kinds of washers in use, drum and Fourdrinier wire washers, presses and diffusers operating at various pressures.
The continuous aim being, for both economical and environmental reasons, to reduce the amount of water consumed per pulp ton, multistage washing methods and plants have been developed wherein the wash filtrate is re-circulated through the pulp at a process stage at which the pulp is less pure than the relevant filtrate. For example, in Finnish patent application 980481, a method of re-circulating washer filtrates is described, which method can be applied to a multistage drum washer. The pulp web to be washed is divided into zones from which the filtrate fractions are individually collected and returned in the counter-flow direction to serve as washing liquids in less pure zones. Multistage washing methods have been developed also for diffusers, as described in U.S. Pat. No. 4,705,600. A multistage wash is particularly difficult to carry out in pressure diffusers, as it is hard to avoid channelling in the pulp and intermixing of the filtrate fractions collected. In U.S. Pat. No. 5,567,262, a two-stage pressure diffuser is disclosed in which the filter unit is divided into two compartments and in which the wash filtrate of the less pure end is returned counter-currently. Further, U.S. Pat. No. 5,482,594 discloses a pulp washer operating at elevated pressure and having two main stages, in which the batch of pulp slurry is first dewatered on a wire table and subsequently carried to a washing position on the table. The recirculation of wash filtrates is also described, wherein filtrate fractions having different concentrations are collected in individual containers and wherein the number of washing stages can be five or more, depending on the number of collecting vessels and on the recirculation order.
DISCLOSURE OF THE INVENTION
BRIEF DESCRIPTION
The method according to claim 1 has now been invented for improving the efficiency of multistage washing, wherein the initial washing of a given batch of pulp is performed by means of a steplessly diluted, recovered filtrate fraction originating from the preceding batch of pulp, prior to the final washing of the pulp batch using available washing water or filtrate coming from the process. In the method, the recovered fraction filtrate is kept stored in such a way, that the concentration gradient of the dissolved substances is maintained until the fraction is used for washing the following batch of pulp, which is not possible in the conventional intermediate fraction tanks in any type of prior art multistage wash A further object of the invention is a pulp washing plant wherein the method according to the invention is carried out in a laboratory-scale test washer and applied to industrial pulp washing plant solutions.
DETAILED DESCRIPTION
FIG. 1 shows a laboratory-scale test plant according to the invention;
FIG. 2 is a schematic view of an industry-scale washing plant according to the invention;
FIG. 3 is a partial view of the upper part of FIG. 2 and shows another embodiment of the washing plant according to FIG. 2, in which the treatment of the batch of pulp to be washed is carried out in an alternative manner.
The basic functional principle of the invention will be explained in more detail in the following, with reference to the accompanying drawing, wherein FIG. 1 shows the principle of a testing plant according to the invention. The main parts of the plant are a pulp washing cylinder 5 , filtrate holding pipes 1 and 1 A and a collecting tank 19 for the leaving filtrate liquor and a control unit 23 for the washing water.
A batch of pulp 27 to be washed is formed in the cylinder 5 as follows: the threaded fastening ring 7 of the cylinder is unscrewed and the washing water distributor head 6 comprising a screen is removed from the top of the cylinder. Valve 13 is closed and three-way valve 14 is opened to wash filtrate outlet pipe 20 . A desired amount of pulp is poured into the cylinder 5 , simultaneously lowering the piston 8 by opening and closing a valve 25 located on the hydraulic water discharge side of the cylinder. The distributor head 6 is put back in place and valve 11 is opened. The coupling 15 of overflow pipe 17 is fitted to coupling 12 of the washing water distributor head. A stopper 10 for limiting piston movement is placed on a circular plate fixed to piston rod 9 , below the cylinder. The height of the stopper determines the upper position of the piston, which ensures that a pulp mat 27 of a constant thickness is always formed between the screen faces. The free air is removed from the cylinder, from above the pulp, by opening and closing a valve 26 located on the hydraulic water feeding side and, consequently, by raising the pulp surface by means of piston 8 to lie against the screen face of the distributor bead 6 and further, until filtrate starts to flow into overflow pipe 17 . The valve 11 is closed and the overflow coupling 15 is removed from coupling 12 of the distributor head. Valve 13 is opened. Raising the piston is continued by opening valve 26 , until piston movement limiting stopper 10 engages. Valves 26 and 13 are closed. A pulp mat 27 has been formed and the mother liquor of the pulp mat formation has been transferred to filtrate liquor collecting tank 19 .
It is assumed, that at this stage holding pipe 1 A is filled with fraction filtrate obtained from the washing of the preceding batch of pulp. Holding pipe 1 A is connected to washing water coupling 2 C by means of a coupling 2 A at its lower end, and to coupling 12 of the washing water distributor head by means of a coupling 3 A at its upper end. All the couplings used in the test plant are hydraulic quick couplings comprising locking spindles. In order to maintain the concentration gradient of the filtrate fraction led from the bottom of the pulp mat 27 during the short period of storage, the filtrate holding pipe 1 A is made of thin, pressure-proof and preferably transparent pipe having an inside diameter of 10 to 15 mm, the inside diameter of cylinder 5 being 100 to 150 mm. The pipe is mounted on a supporting structure having an outside diameter of 150 to 250 mm as a spiral of such length that it can hold an amount of fraction filtrate at least 1 to 2 two times larger relative to the basic amount of liquor in the pulp cake. This results in a washing efficiency 2 to 4 times greater compared with a normal single stage wash. The filtrate to be displaced has the highest concentration of dissolved substances at the beginning of the wash, after which the concentration of the solution gradually declines as washing proceeds. Thus, the filtrate portion having the lowest concentration lies in the bottom part of holding pipe 1 A, in front of the washing water coupling 2 A, and the filtrate amount having the highest concentration has moved, during the filling of the holding pipe, to the upper end thereof, closer to the pulp mat 27 to be washed. The fraction filtrate holding vessel 1 , which is identical to 1 A as far as dimensions and fittings are concerned, is empty and connected to a filtrate liquor inlet coupling 2 B by means of a coupling 2 at its lower end and is in ventilating connection with the overflow pipe 18 via couplings 3 and 16 and an open valve 28 .
The washing of the pulp mat is performed as follows: Valves 11 and 13 and the washing water control valve 22 are opened, and the unit 23 for controlling the amount of washing water is started. If the aim is to perform the washing in a pressurised state and, consequently, to affect the behaviour of the air in the system, the control unit 23 is allowed to control valve 13 instead of valve 22 . However, valve 13 is not opened and washing is not started until the desired pressure has been reached in the washing chamber of the pulp mat 27 with the aid of the pressurised washing water. Starting to move, the washing water pushes the fraction filtrate stored in holding pipe 1 A ahead of it, through the pulp mat 27 , with the result that the most concentrated fraction filtrate thereof displaces the most concentrated mother liquor from the mat directly into the wash filtrate tank 19 through pipe 20 . The control unit 23 estimates how much filtrate is discharged into the wash filtrate tank and indicates when the desired volume is reached. At this stage, three-way valve 14 is immediately turned into its second position, so that the wash filtrate required in the continuous fraction wash is directed into fraction holding pipe 1 , beginning to fill it. After the fraction wash filtrate has run out, the washing of the pulp mat continues uninterrupted using the regular washing water available, until unit 23 for controlling the amount of washing water sends an impulse to close washing water valve 22 . Valve 22 is closed immediately, as well as valves 11 and 13 . The shifting of wash filtrate flow destination from wash filtrate collecting tank 19 to fraction pipe 1 using three-way valve 14 is timed in the control unit in such a way, that the smallest possible amount of fraction filtrate (the most concentrated filtrate, however) is carried directly into collecting tank 19 through overflow pipe 18 . If the washing is performed in a pressurised state, it is possible to increase the pressure in fraction vessel 1 by choking ventilation valve 28 , preventing the hot filtrates from swelling in the fraction vessel. Couplings 2 and 3 of holding pipe 1 , which is full of washing water, are unconnected. Coupling 3 A is disconnected from coupling 12 of the distributor head and it is connected to coupling 16 of ventilation pipe 18 . Valve 24 is opened and the washing water is allowed to drain from holding pipe 1 A. The piston movement limiting stopper 10 is removed, the fastening ring 7 is unscrewed and the washing water distributor head 6 and the pulp mat 27 are pushed out of the cylinder with piston 8 . Drain valve 4 is opened and the filtrate stored in the pipe system is emptied into container 21 . The filtrate is recovered and the amounts of chemicals therein are taken into account when calculating the washing factors. The three-way valve 14 is turned toward pipe 20 . The coupling 2 A of tubular vessel 1 A, which is drained of washing water, is disconnected from washing water coupling 2 C and shifted to coupling 2 B. The unconnected coupling 2 of the lower end of holding pipe 1 and coupling 3 of the upper end thereof are connected to washing water coupling 2 C and to coupling 12 of the washing water distributor head, respectively.
A new batch of pulp can now be washed in the testing plant. The operations are the same as described above except for the filtrate holding pipes 1 and 1 A that always have reversed functions after each washing of a new batch of pulp.
When studying fractional washing by means of the test washer, it was observed that to reach an acceptable equilibrium for the liquor concentrations in the fraction filtrate pipe, the washing operation described above must be performed 5 to 8 times in succession using the same amounts of pulp and washing water, the testing conditions being as identical as possible.
FIG. 2 shows the principle of an industry-scale plant according to the invention. The main parts of the plant are pulp washer 29 , filtrate tanks 30 and 30 A corresponding to the holding pipes 1 and 1 A of the testing plant described above, and tanks for the leaving filtrate liquor 39 and for the washing water 38 .
When the operation is started, tank 30 A is full of filtrate obtained from the washing of a pulp batch of a given size. In order to maintain the concentration gradient of the filtrate fraction pumped out of the bottom of the pulp batch 31 , tank 30 A is of a cellular design; thus, vertical partition walls 50 divide the tank into a plurality of narrow cells 51 extending in the direction in which the flow passes through the tank, preferably providing a honeycomb-shaped cross section. The filtrate first displaced from the batch of pulp to be washed has the highest concentration of dissolved substances. This spreads over the whole width of the tank bottom, from where the filtrate rises into all empty cells. Any small differences in flow rate that may occur at the beginning of the filling disappear immediately due to gravity, and as the liquid level rises, the filtrate fractionates in the tank, in the same way over the whole width all the way to the top end. Thus, when tank 30 A is full, the least concentrated part will lie in the lowest part thereof, above the inlet connection, and the most concentrated part of the filtrate in the upper part, below the outlet connection. The filling of the tank from below upward enhances the separation of air from the filtrate, and it can be removed from above the liquid surface of the tank in the filtrate overflow stage at the latest. When the operation cycle starts, tank 30 is empty. A new batch of pulp 31 to be washed has been formed in washer 29 . All valves are closed.
Washing of the pulp 31 is started by a pre-wash. The pumps 32 and 33 start. The valves 34 A, 35 , 36 and 37 A open to their set values. Washing water flows from the tank 38 into the lower part of the tank 30 A, pushing the filtrate fraction in the tank ahead of it The distribution of the displacement liquid evenly over the whole cross-sectional area of the tank having a large diameter can be ensured using a separate washing water inlet pipe system and choke nozzles, which are not shown in FIG. 2 . The filtrate leaving via the upper end of the fraction tank and having the highest concentration of dissolved substances penetrates into the pulp layer 31 , displacing most of the mother liquor into a filtrate liquor tank 39 through a valve 36 . When a predefined amount, for example 1.2 times the liquid volume of the pulp layer, has been displaced, valve 36 closes. Valve 40 opens and the after-washing stage begins.
The pumping of washing water from tank 38 into tank 30 A continues. The filtrate leaving the pulp is stored in tank 30 , which is identical to tank 30 A When tank 30 becomes fill, the flow can continue, for a given time, as overflow into an air separation and overflow cyclone 41 through valve 35 and further into filtrate liquor tank 39 . Once the washing is completed, the valves 37 A, 34 A, 35 and 40 close and the pumps 32 and 33 stop. The ventilation valve 35 A and the drain valve 43 A open, with the result that the unused washing water flows from tank 30 A back into the washing water tank 38 . Valve 43 A closes. The washed pulp layer 31 leaves the washer 29 . Valve 42 opens and the last, purest filtrate fraction is led back into the washing water pipe system, to the front of the pump 33 to be used as washing water, as the first litres of the flow in the following wash. Valve 42 closes.
A new layer of pulp 31 is forming in the washing chamber of the washer 29 and a new washing cycle can begin. The operation is identical to the washing operation described above except for the fact that the function of tanks 30 and 30 A and their corresponding valves have been reversed. In FIG. 2, the washer 29 is shown as an apparatus in which the pulp layer moves in the horizontal plane, as in a Fourdrinier wire washer. The apparatus described in U.S. Pat. No. 5,482,594 mentioned above is an example of such a device. In this case, the washing chamber may have a screen face only at the bottom. The invention can also be applied to batch-type twin wire precipitation devices. Furthermore, a plant using the technique according to the invention can be provided with a vertical pulp path by applying, for example, the technology described in U.S. Pat. No. 5,567,262. FIG. 3 is a schematic view of the upper part of such a plant; in other respects and as far as reference numbers are concerned, the figure is identical to the upper part of FIG. 2 . The method can, for example, be applied to a continuous process by using prior art methods according to the diffuser principle, in which case the periodically operating fractional washing is completed during the time while the assembly composed of the washing water distributor screen and the pulp mat washing screen ran parallel along the main pulp flow in the diffuser.
A new unwashed batch of pulp is generated between the washing water distributor screen and the washing screen when the screen package is jolted back to its initial position.
The production capacity of the plant according to the invention can be estimated as follows: P = v * et * A * D * 8 , 64 S * 100 - c in / c in + ( 100 - c out ) / c out + DF
wherein
P=production capacity, ODT/24h
v=speed of the wash filtrate, cm/s determined using the testing plant according to FIG. 1, for example
et=effective washing time of a single washing cycle as a percentage
A=filtration area available for the wash, m 2
D=density of the washing liquid, t/m 3
S=number of mother liquor displacements at the fractional wash stage
c m =pulp consistency in the mat, %
c out =consistency of the leaving, washed pulp, %
DF=dilution factor of the wash, t/ODT
If the values are v=0,7, et=80, D=1, S=1,5, c m =c out =10 and DF=2,5, for example, a 24-hour production capacity of approximately 19,4 ODT per square meter is achieved. | A method of improving the efficiency of the multistage washing of pulp, wherein the initial washing of a given batch of pulp is carried out using a gradually diluted, recovered filtrate fraction originating from the washing of the preceding batch of pulp as the washing liquid, prior to the final washing of the pulp batch. In the method, the recovered fraction filtrate is kept stored in such a way that the concentration gradient of dissolved substances is maintained until the fraction is used for washing the following batch of pulp. A further object of the invention is a pulp washing plant, wherein the method according to the invention is carried out in a laboratory-scale test washer and applied to industrial pulp washing plant solutions. | 3 |
BACKGROUND
1. Field of the Invention
Embodiments of the invention relate to methods of making titania nanostructures and more particularly to electrochemical methods of making titania nanostructures.
2. Technical Background
Metal oxides are material systems explored, in part, due to metal oxides having several practical and industrial applications. For example, titanium (IV) oxide (titania) is used in a wide range of applications such as in paints, cosmetics, catalysis, and bio-implants.
Nanomaterials possess unique properties that are not observed in the bulk material, for example, the optical, mechanical, biochemical and catalytic properties of particles are closely related to the size of the particles. In addition to very high surface area-to-volume ratios, nanomaterials exhibit quantum-mechanical effects which can enable applications that are otherwise impossible using the bulk material. One of the challenges with nanotechnology is the manufacture of nanomaterials in an economically viable process. As a result, only a very few nanotechnology based applications have been commercialized, although a wide spectrum of nanotechnology based applications have been demonstrated on a laboratory scale.
Titania, for example, is a material system where nanotechnology based applications have been demonstrated on a laboratory scale and where the nanomaterials could be used in a wide range of practical applications. Titania nanomaterials can be used, for example, in photovoltaic applications such as dye-sensitized solar cells, metal-semiconductor Junction Schottky Diode solar cells, and doped-TiO 2 nanomaterials based solar cells. Titania nanomaterials can be used in photocatalysis, photo-degradation of various organic pollutants, for example, Rhodamine B, Chloroform, Acid Orange II, Phenol, Salicylic Acid, and Chlorophenols. Further, titania nanomaterials are useful in hydrogenation reactions, for example, hydrogenation of propyne (CH 3 CCH), photocatalytic water splitting. Also, titania nanoparticles can be used in electrochromic devices such as electrochromic windows and displays, in hydrogen storage, in sensing applications, for example, humidity sensing and gas sensing such as in hydrogen, oxygen, carbon monoxide, methanol, and ethanol sensors. Titania nanomaterials can be used in lithium batteries as insertion electrodes.
There are several conventional methods for the synthesis of titania nanomaterials, for example, sol-gel, micelle and inverse micelle, sol, hydrothermal, solvothermal, direct oxidation, chemical vapor deposition, physical vapor deposition, electrodeposition, sonochemical, microwave, organic templated synthesis, aerogel, and TiO 2 nanosheets, for example, through delaminated layer synthesis from protonic titanate.
In conventional sol-gel methods, a colloidal suspension or sol is formed from precursors, typically inorganic metal salts or metal-organic compounds, for example, metal alkoxides through hydrolysis and polymerization reactions. Loss of solvent and complete polymerization leads to the transition into a sol-gel phase which is then converted into a dense ceramic through further drying and heat treatment. Typical synthesis of titanium oxide nanomaterials using the sol-gel method includes adding titanium alkoxide (e.g. titanium tetraisopropoxide) precursor to a base such as tetramethyl ammonium hydroxide at 2° C. in alcoholic solvents. This is followed by heating at from 50° C. to 60° C. for 13 days or at from 90° C. to 100° C. for 6 hours and finally subjecting to a secondary treatment involving heating in an autoclave or high-pressure reactor at from 175° C. to 200° C.
Conventional sol-gel methods employ extreme process conditions, for example very low temperature to high temperatures and pressures with high energy requirements, requires high pressure reactors with increased capital costs and uses chemicals, for example, isopropoxides that involve increased handling costs.
In conventional hydrothermal methods, hydrothermal synthesis is performed in an autoclave or high pressure reactor with Teflon 4 liners under controlled temperature and pressure with the reactions occurring in aqueous solutions.
A variation of this method is the solvothermal method wherein organic solvents are used instead of an aqueous environment. Typical synthesis of titanium oxide nanowires involves reacting titanium chloride with an acid or inorganic salt at from 50° C. to 150° C. in an autoclave for 12 hours. This is followed by washing powders of nanomaterial in DI water and ethanol and drying at 60° C. for several hours.
Some of the other conventional hydrothermal methods for making titania nanoparticles are hydrothermal reaction of titanium butoxide (in isopropanol) with water (water:Ti ratio of 150:1) at 70° C. for 1 hour followed by filtration and heat treatment at 240° C. for 2 hours and finally washing in DI water and/or ethanol and drying at 60° C.; hydrothermal reaction of titanium alkoxide precursor in acidic ethanol-water solution at 240° C. for 4 hrs followed by washing and drying; and a method of making TiO 2 nanowires through a hydrothermal treatment of TiO 2 powder in from 10 molar to 15 molar sodium hydroxide at from 150° C. to 200° C. for from 24 hours to 72 hours followed by washing and drying.
Conventional hydrothermal methods have disadvantages similar to the sol-gel method, for example, high cost autoclaves, use of chemicals that require careful handling, in addition to being time-consuming and having expensive post-processing treatments.
In conventional electrodeposition methods, titania nanowires are deposited using an anodic alumina membrane (AAM) as template. The synthesis is carried out in a titanium chloride solution (at pH=2) using pulsed electrodeposition. The substrate is subsequently heated to 500° C. for 4 hours followed by removal of the AAM template. A prerequisite for this method is the availability of a template that can be removed without leaving any residue using a moderate removal process. Otherwise, regular electrodeposition yields bulk sized particles. Additionally, handling of corrosive electrolyte like titanium chloride in an industrial process can be challenging.
In conventional direct oxidation methods, synthesis of titania nanotubes involves applying a voltage of from 10 volts to 20 volts for from 10 minutes to 30 minutes between two titanium plates in a 0.5% hydrogen fluoride (HF) solution. The use of HF makes this process unattractive for industrial production. Also, the shape of the nanostructures obtained is limited to nanotubes.
Conventional methods of making titania nanostructures are energy intensive, employ expensive capital equipment, for example, high pressure reactors, involve tedious process steps, for example, cleaning, washing and drying of powders, and use nonbenign chemicals, for example, alkoxides, titanium chloride, and HF.
It would be advantageous to have method of making titania nanomaterials in large quantities in an economically viable fashion.
SUMMARY
Methods of making titania nanostructures, as described herein, address one or more of the above-mentioned disadvantages of conventional methods of making titania nanostructures and provide one or more of the following advantages: increased compositional and size control with reduced capital and/or manufacturing costs and, since the nanostructures can be grown directly on substrates, the nanostructures possess an inherently high electrical conductivity. Inherently high electrical conductivity is particularly useful in photovoltaic and photocatalytic applications and can lead to materials and systems with improved architecture.
One embodiment of the invention is a method of making titania nanostructures. The method comprises providing an electrolytic cell, which comprises an anode and cathode disposed in an electrolyte, wherein the anode and cathode each comprise a titanium surface exposed to the electrolyte; and applying an electrical potential to the electrolytic cell for a period of time sufficient to obtain titania nanostructures on the titanium surfaces of the anode and cathode.
Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the invention as described in the written description and claims hereof, as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s) of the invention and together with the description serve to explain the principles and operation of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be understood from the following detailed description either alone or together with the accompanying drawing figures.
FIG. 1 is an electrolytic cell used in a method according to one embodiment.
FIG. 2 a and FIG. 2 b show the cyclic voltammetry of a Ti substrate.
FIG. 3 a , FIG. 3 b , FIG. 3 c , FIG. 3 d are SEM micrographs of titania nanostructures made according to one embodiment.
FIG. 4 a , FIG. 4 b , FIG. 4 c , FIG. 4 d are SEM micrographs of Ti electrodes.
FIG. 5 a , FIG. 5 b are SEM micrographs of titania nanostructures made according to one embodiment.
FIG. 6 a , FIG. 6 b are SEM micrographs of titania nanostructures made according to one embodiment.
FIG. 7 a , FIG. 7 b are cross-sectional SEM micrographs of the embodiment shown in FIG. 5 a.
FIG. 8 a , FIG. 8 b , FIG. 8 c , FIG. 8 d are a series of SEM micrographs at increasing magnifications of the embodiment shown in FIG. 6 a.
DETAILED DESCRIPTION
Reference will now be made in detail to various embodiments of the 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.
One embodiment of the invention is a method of making titania nanostructures. The method comprises providing an electrolytic cell 100 , as shown in FIG. 1 , which comprises an anode 10 and cathode 12 disposed in an electrolyte 14 , wherein the anode and cathode each comprise a titanium surface 16 exposed to the electrolyte; and applying an electrical potential to the electrolytic cell for a period of time sufficient to obtain titania nanostructures on the titanium surfaces of the anode and cathode. The potential can be applied via a power supply 18 , for example, a direct current (DC) power supply which can supply a constant voltage or a bipotentiostat, for example, which can supply a cyclic voltage. In one embodiment, the electrolyte is a solution comprising sodium hydroxide, potassium hydroxide, or combinations thereof. The solution, in some embodiments, can be at a concentration of from 3 molar to 8 molar, for example, 5 molar.
In one embodiment, the anode and cathode independently comprise a material selected from titanium metal, titanium foil, titanium film disposed on a conductive support, titanium film disposed on a non-conductive support, and combinations thereof. The conductive support, in some embodiments, comprises a material selected from ITO, copper, and combinations thereof. The conductive support, in some embodiments, is any conductive metallic substrate. The non-conductive support, in some embodiments, comprises a material selected from a polymer, plastic, and combinations thereof. The potential can be 0.6 volts or more, for example, in the range of from 0.6 volts to 5.0 volts. The potential, in some embodiments, is applied continuously for from 30 minutes to 24 hours, for example, for 4 hours to 18 hours. The method can further comprise cleaning the substrates prior to contacting the electrolyte.
The titanium film can be, for example, a thin film or a thick film of Ti metal. The thin film can be, for example, from a few nanometers in thickness to a few microns in thickness. The thick film can be, for example, from tens of microns in thickness to several hundreds of microns in thickness. The electrical conductivity of the Ti surface can facilitate electron transfer at the solid-liquid interface and the electrical connection given to the Ti portion of the substrate. The substrate can be a flat surface or can be a non-flat (flexible) surface.
The method can be used at ambient conditions, for example, room temperature and atmospheric pressure and can utilize low voltage and current, thus, lower energy.
According to one embodiment, the method further comprises cleaning the anode and the cathode after obtaining the titania nanostructures. The cleaning, in some embodiments, comprises acid washing. The acid can be selected from hydrochloric, sulfuric, nitric, and combinations thereof.
EXAMPLES
Annealed, 99.5% titanium substrates available from Alfa Aesar were cut and cleaned by being sonicated in 1:1:1 mixture of acetone, iso-propanol, and water for 15 minutes. The titanium substrates were then rinsed in deionized (DI) water and further sonicated in DI water for 15 minutes. The titanium substrates were dried under a stream of nitrogen.
The electrolyte was prepared using certified ACS sodium hydroxide and certified ACS potassium hydroxide, both available from Alfa Aesar, in DI water.
Electrolytic cells, for example, electrochemical cells of different sizes (1.5″×1″×1″ and 3″×1.5″×3.5″ internal dimensions) were made using Teflon. Teflon was chosen since Teflon is stable in basic environment as opposed to glass or metal vessels that can be susceptible to etching and/or corrosion effects. Other materials that are resistive to a basic pH can be used to build the electrochemical cells.
A bipotentiostat, model AFRDE5, available from PINE Instrument Company, Grove City, Pa., was used to perform cyclic voltammetry methods. Constant voltage methods were performed using a DC power supply, Model E36319, available from Agilent. In the examples, similarly sized Ti substrates were used as both the anode and as the cathode.
FIG. 2 a and FIG. 2 b show the cyclic voltammetry of a Ti substrate in 1 molar (M) NaOH and 1M KOH solutions. As shown in FIG. 2 a , during the anodic cycle (positive sweep) there are no surface reactions up to a potential of about 0.6 volts (V) (as indicated by zero current). At potentials above 0.6 V, the current increases indicating the onset of oxidation reactions on the surface. As the surface potential is increased, a peak is observed at 1.6 V denoting a diffusion-limited electrochemical reaction.
It can be hypothesized that the reaction is a surface oxidation process that may be limited by the mass transfer of the hydroxyl ions towards the electrode surface. At a potential of 2.3 V, the current increases to further positive values indicating a second electron-transfer reaction. From the trajectory of the current vs. potential curve above 2.3 V, it can be hypothesized that this second electron-transfer reaction is a kinetically controlled oxidation reaction that is not affected by the concentration of hydroxyl ions in the solution (at least at concentrations >1 M). The cyclic voltammetry can be used as a guide for predictive experimentation, i.e. the potential to be applied can be chosen to influence reaction-specific changes to the surface of the anode and/or the cathode.
FIG. 2 b shows the cyclic voltammetry of a Ti substrate in 1M KOH. The electrochemical behavior of Ti in KOH and the electrochemical behavior of Ti in NaOH electrolytes are different, although the pH of the two solutions is the same. The Ti surface of the substrate is unaffected at potentials below 0.8 V. At potentials above 0.8 V, a diffusion-controlled oxidation reaction up to a potential of 5 V as indicated by a single peak with positive current. Similar to that from the NaOH system, the cyclic voltammetry of Ti in the KOH electrolyte can be used a guide for predictive experimentation to control the surface reactions and eventually surface structure and/or composition.
Pre-cleaned titanium substrates (anodes and cathodes) were placed vertically against the opposing faces of a Teflon cell. The cell was then filled with electrolyte (NaOH or KOH or a combination of both). For the examples conducted in the small cell (1.5″×1″×1″), 15 mL of electrolyte volume was used and for the examples in the larger cell (3″×1.5″×3.5″), 150 mL of electrolyte was used. The substrates were then connected to a DC power supply which applied a preset voltage across the two substrates, now electrodes. The voltage was chosen based on the cyclic voltammetry results previously described. Several examples were performed by systematically changing various experimental conditions. The results are discussed below.
Titanium electrodes (anode and cathode) were subjected to electrochemical control, for example, a constant potential control, in NaOH and KOH solutions. Solution concentrations of 1 M, 5 M and 10 M were tested and it was found that 5 M solutions produced the desired titania nanostructures. No or very little nanostructures were observed on the electrodes that were prepared in 1 M solutions, even at increased times. In 10 M solutions, although surface roughness was observed after electrochemical control, feature sizes were several hundreds of micrometers with little evidence of nanometer sized structures.
Based on the above described results, there is an optimal electrolyte composition range at which TiO 2 nanostructures can be formed electrochemically. Henceforth herein, the examples pertain to 5 M solutions of NaOH or KOH or combinations thereof.
Controls corresponding to each electrochemical example were prepared by immersing Ti substrates in the respective electrolyte for the respective time without any applied potential. Electrodes were also subjected to varying time (i.e. the time under electrochemical control). For the electrodes with electrochemical control for 30 minutes and 2 hours, no nanostructures were observed both in NaOH and KOH solutions. Scanning electron microscope (SEM) micrographs of these electrodes (not shown) were similar to those of the controls.
FIG. 3 a , FIG. 3 b , FIG. 3 c , and FIG. 3 d are SEM micrographs of Ti substrates that were subjected to a constant potential of 5 V for 6 hours in 5 M NaOH solution. FIG. 3 a and FIG. 3 c correspond to those of the anode (i.e. the surface experiences a positive potential) and FIG. 3 b and FIG. 3 d correspond to those of the cathode (i.e. the surface experiences a negative potential).
FIG. 3 a and FIG. 3 b are SEM micrographs of the Ti substrates after being rinsed in DI water and dried under a nitrogen flow following electrochemical processing. The titania nanostructures comprise an open (porous) network 18 connected by short, nanometer sized (width) TiO 2 nanowires 20 . The “grainy” features are due, in part, to the presence of the leftover NaOH that did not wash out during DI water rinse. This was confirmed by the presence of sodium peaks in X-ray diffraction (XRD) analysis.
FIG. 3 c and FIG. 3 d are SEM micrographs of the substrates after being rinsed, acid-washed and dried following electrochemical processing. For the acid-wash step, the substrates were immersed in a mild acid, for example, 1 M HCl, for 30 minutes followed by rinsing in DI water. Well defined titania nanostructures similar to those observed in FIG. 3 a and FIG. 3 b are present sans the graininess. This is due, in part, to the complete removal of NaOH by acid-washing. The titania nanostructures comprise an open (porous) network 18 connected by short, nanometer sized (width) TiO 2 nanowires 20 . This represents a very high surface area surface with very good electrolyte access to the entire surface through open pores.
The sizes of the nanowires in these networks ranged between from 10 nm to 40 nm with an average around 30 nm. These high-surface area structures possess an increased accessibility for liquids or gases to the entire surface area or gases which is an advantageous attribute in applications where material utilization is to be maximized (e.g. photovoltaic cells).
Although the exact mechanism of the creation of these nanostructures is unclear currently, a dissolution-redeposition mechanism can be hypothesized, wherein the electrolyte accesses a maximum nm 2 of the surface during the synthesis process. Since the nanostructures are grown into the metal substrate, the nanostructures possess increased electron accessibility and electrical conductivity.
FIG. 4 a , FIG. 4 b , FIG. 4 c , and FIG. 4 d are SEM micrographs of Ti electrodes that were subjected to a constant potential of 5 V for 6 hours in 5 M KOH solution. FIG. 4 a and FIG. 4 c correspond to those of the anode and FIG. 4 b and FIG. 4 d correspond to those of the cathode.
FIG. 4 a and FIG. 4 b are SEM micrographs of the Ti substrates after being rinsed in DI water and dried under a nitrogen flow following electrochemical processing.
FIG. 4 c and FIG. 4 d are SEM micrographs of the substrates after being rinsed, acid-washed and dried following electrochemical processing. For the acid-wash step, the substrates were immersed in a mild acid, for example, 1 M HCl, for 30 minutes followed by rinsing in DI water. No to minimal discernible nanostructures were formed under these conditions. FIG. 4 a appears to have some structure on the surface, of which disappears after acid wash, as shown in FIG. 4 c.
FIG. 5 a and FIG. 5 b are SEM micrographs of Ti substrates processed under a constant potential control of 5 V for 16 hours in 5 M NaOH solution. FIG. 5 a corresponds to the anode and FIG. 5 b corresponds to the cathode.
As shown in FIG. 5 a , the surface exhibits webbed titania nanostructures with the connecting titania nanowires 22 having finer sizes as compared to the 6 hour electrode, shown in FIG. 3 a . The average sizes of the titania nanowires are less than 10 nm and several titania nanowires are bundled together forming a high surface area network. On the other hand, the titania nanostructures 24 on the counter electrode seem to have collapsed, since they are more closed than the corresponding 6 hour electrode, shown in FIG. 3 b , possibly due to some sort of a coalescence effect. Nevertheless, these disordered structures are still in the sub-100 nm regime.
FIG. 6 a and FIG. 6 b are SEM micrographs of Ti substrates processed under a constant potential control of 5 V for 16 hours in 5 M KOH solution. FIG. 6 a corresponds to the anode and FIG. 6 b corresponds to the cathode.
As compared to the 6 hour electrodes shown in FIG. 4 a and FIG. 4 b which did not exhibit titania nanostructures, both the anode and the cathode possess an interwoven network of titania nanostructures 26 , for example, titania nanowires. The titania nanowires have high surface area and good accessibility to the titania nanostructures even deep into the substrate. The anode possesses uniform distribution of sub-10 nm sized titania nanowires while the cathode possesses titania nanowires that are predominantly around 30 nm. An advantageous feature of the titania nanostructures is the amount of surface connectivity. The titania nanowires are intricately and inseparably connected to each other to the point where it is almost impossible to identify the start and end of any given strand of titania nanowire.
Also, it is clear that the surface structure of the titania nanostructures can be manipulated by manipulating processing conditions such as electrolyte composition, time, electrode polarity (anode vs. cathode), electrode potential or combinations thereof.
FIG. 7 a and FIG. 7 b are cross-sectional SEM micrographs of the 16 hour electrode synthesized in 5 M NaOH (anode) shown in FIG. 5 a . The titanium to titania interface 28 illustrates a good substrate-to-nanostructure connectivity. The layer of titania nanostructures 30 across the titanium substrate 32 is fairly uniform. The average thickness of the layer of nanostructures is around 500 nm.
The thickness can be controlled, for example, by controlling the time of electrochemical control within the optimum time range, as too little (<6 hours) or too high a time will not yield the desired nanostructures. For example, a 72 hour experiment (Ti under potential control in KOH or NaOH) caused the collapse of nanostructures; this might be due to the mechanical collapse of the nanostructures as Ti surface is continually being subjected to continuous dissolution-redeposition.
Table 1 shows the summary of XRD analysis performed on the Ti electrodes synthesized in 5 M NaOH and 5 M KOH solutions for 16 hours under electrochemical control. The electrodes were subjected to heat-treatment prior to XRD analysis. The heat treatment comprised heating the electrodes to 500° C. at a rate of 10° C. per minute and holding at 500° C. for 1 hour.
TABLE 1
Phases detected
Electrolyte
Electrode
from XRD analysis
NaOH
Control (no electrochemistry)
Ti metal
Anode
Ti metal
TiO 2 - Rutile
TiO 2 - Anatase
Cathode
Ti metal
TiO 2 - Rutile
KOH
Control (no electrochemistry)
Ti metal
Anode
Ti metal
TiO 2 - Rutile
TiO 2 - Anatase
Cathode
Ti metal
TiO 2 - Rutile
The controls in both the electrolytes did not yield any oxides showing that the surface remained in the metallic state. The anode (working electrode) in both cases showed the presence of metallic Ti and Rutile and Anatase phases of TiO 2 . The metallic phase is the background from the Ti substrate. The cathode (counter electrode) exhibited the presence of only the Rutile phase of TiO 2 in addition to the Ti metal background from the substrate.
This feature could be favorably exploited to selectively synthesize TiO 2 nanostructures with a desired phase or phases. The nanostructures remained intact after heat treatment. Also, one could subject these electrodes to further heat treatment to obtain the desired phases.
FIG. 8 a , FIG. 8 b , FIG. 8 c , and FIG. 8 d are a series of SEM micrographs of the 16 hour anode synthesized in KOH solution taken at increasing magnifications (500×, 2500×, 10,000× and 25,000×) shown in FIG. 6 a . This electrode was chosen for illustrative purposes only; other electrodes show similar behavior. Moving from FIG. 8 a through 8 d , the titania nanostructures are formed uniformly across the entire surface and not merely discrete islands of nanostructures.
This is an advantage of using an electrochemical process where the entire surface can be manipulated uniformly. This has an important implication in terms of scalability and manufacturability of this process. A bigger substrate along with a bigger electrochemical cell can be used to manufacture various quantities (few mm 2 to several m 2 ) of TiO 2 nanostructures.
In one embodiment, the method comprises making the titania nanostructures in a batch process. In another embodiment, the method comprises making the titania nanostructures in a continuous process.
The process could be a batch process where sheets of Ti or Titanium coated substrates (for example, a Ti film on an indium tin oxide (ITO) or a copper substrate or a Ti film on a polymer substrate such as polyethylene terephthalate (PET)) can be immersed in the electrolyte (NaOH or KOH) and nanostructures created by applying an electric potential.
Another embodiment that could be envisioned is a continuous process wherein two Ti or Ti coated substrate rolls could be continuously fed into a tank containing NaOH or KOH while electric potential is being applied. A downstream cleaning and/or rinsing step could be integrated producing rolls of TiO 2 nanostructured surfaces. Also, since the reaction is limited to the surface that is in contact with the electrolyte, excellent process control can be achieved. In both embodiments, the process can be monitored by monitoring the current as a function of time.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. 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. | Electrochemical methods for making titanium oxide (TiO 2 ) nanostructures are described. The morphology of the nanostructures can be manipulated by controlling reaction parameters, for example, solution composition, applied voltage, and time. The methods can be used at ambient conditions, for example, room temperature and atmospheric pressure and use moderate electric potentials. The methods are scalable with a high degree of controllability and reproducibility. | 2 |
This application is a continuation-in-part of U.S. application Ser. No. 09/429,064, filed Oct. 29, 1999, now U.S. Pat. No. 6,196,777 B1.
The present invention relates to an implement that is attachable to a load carrying vehicle and is operative to secure or hold loads carried in the vehicle.
BACKGROUND
Vehicles such as pick-up trucks are incapacitated in their ability to accommodate cargo securing straps or lines because the sides of the truck bed are rarely, if ever, provided with sufficient rings, rails, brackets or holes by which a cargo securing strap can be anchored to the vehicle.
In some instances it is desirable to tie bulky cargo so that it will not move around in the bed of the truck or worse, leave the vehicle. In some instances it is desirable to position and hold certain types of loads in order to make room for other cargo, for example securing a bicycle in an upright position next to the side of the truck bed. Neither of these occasions are well served by the absence of anchoring facilities on pick-up trucks or similar vehicles.
It is, therefore, the primary object of the present invention to provide a universal cargo anchoring device that is readily attachable to the rolled upper edge of the side of a pick-up truck, dump truck or similar vehicle.
Secondarily, it is an object of the invention to provide a universal load anchoring device that can be attached to other portions of a vehicle or even a non moving structure.
Another object of the invention is to provide an anchor attachable to a structure, including a vehicle, that will support a shaft, axle or the like for the mounting of pivotal structures.
Other and still further objects, features and advantages of the present invention will become apparent upon a reading of the following detailed description of a preferred and alternative embodiments of the invention.
SUMMARY OF THE INVENTION
The cargo anchoring implement of the present invention comprises a journal box for a shaft and an integral screw operated clamping device for attaching the journal box to a supporting structure, such as, for example, the side of the bed of a pick-up or dump truck. In this specification and the concluding claims, the anchoring device will be explained in terms of its intended use with an open bed truck such as a pick-up truck, but the general explanation is intended to include all such types of trucks that have upstanding bed sides that can present a purchase area for the clamping part of the anchoring device. The rolled or bent over upper edges of the sides of the open bed of a pick-up truck provided the exemplar to explain the various embodiments of the invention. The anchoring device can also be utilized on fixed structures.
The journal box includes a base member and an adjustable pressure cleat that is superimposed on the base member. The base member functions not only as part of the journal box but also as part of the clamping device. A bore traverses the journal box and is located so that a shaft journalized in the bore and sandwiched between the base member and the cleat can, depending on the diameter of the shaft and the adjustment of the pressure exerted by the cleat, be allowed to rotate and move longitudinally within the bore or be locked in a selected rotational and longitudinal position within the bore. The shaft serves to support pivotally rotatable load carrying rack elements or to hold load fastening means such as a strap, line, band, chain, rope, belt or to hold a ring for receiving such items.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the anchoring device of the present invention as it would appear attached to the rolled, or bent over, upper edge of the side of the bed of a pick-up truck (shown fragmentarily in dotted lines). The crank arm and pedal of a bicycle loaded into the truck bed is fragmentarily shown in dotted lines.
FIG. 2 is an exploded view of the anchor shown in FIG. 1 .
FIG. 3 is a perspective view of the anchor of the present invention with a straight shaft journaled by the journal box.
FIG. 4 is a fragmentary perspective view of the bed and lateral sides of a pick-up truck with a fragmentary view of the lower braces of a collapsible cargo rack that are mounted for pivotal movement on the shaft of the anchor embodiment shown in FIG. 3 . The anchors of FIG. 3 are shown for illustrative purposes as mounted on only one side of the bed of the truck, however, in practice, the anchors and braces would normally be on both sides.
FIG. 5 is a perspective view of a third embodiment of the anchor. A “D” ring is rotatably secured in a transverse bore in the journal box.
FIG. 6 is an exploded view of a further embodiment of the anchor of the present invention with a screw activated clamping plate that attaches to the top of the bed liner instead of the “C” type clamp utilized by the forgoing described embodiments. The side of the bed of the pick up truck and the bed liner are fragmentarily shown.
FIG. 7 is a cross sectional view of the bed of a pick up truck having a bed liner. The anchor embodiment shown in FIG. 3 is shown attached to the top edge of the bed liner, as more fully shown in FIG. 6 .
FIG. 8 is a perspective view of another embodiment of the anchor clamp of the present invention with the rolled, or bent over, upper edge of the side of the bed of a pick-up truck to which the anchor may be applied shown in dotted lines.
FIG. 9 is a vertical cross sectional view of the anchor clamp that is illustrated in FIG. 8, except that the cleat is not shown in FIG. 9 .
FIG. 10 is similar to FIG. 9 except that the threaded clamping stem is shown in a pivoted position away from its position as shown in FIG. 9 .
FIG. 11 is a perspective view of the anchor clamp of FIG. 8 except that the separate cleat shown in the FIG. 8 embodiment has been replaced with an integrally formed cleat.
FIG. 12 is a vertical cross section of the anchor clamp shown in FIG. 11 .
DETAILED DESCRIPTION
For a detailed description of the various embodiments of the invention, we turn first to FIGS. 1 and 2. The preferred form of the anchor 2 comprises a journal box 4 and an integral clamping device 6 . The journal box 4 includes a flat base member 8 and a superimposed cleat 10 that is adjustably secured to the base member by a pair of screws 12 . The cleat 10 is provided with a transverse bore 14 that journals a cylindrical shaft 16 . The shaft is sized and dimensioned so that the pressure exerted by the cleat 10 to sandwich the shaft between the cleat and the base member 8 can be adjusted to either lock the shaft in a fixed position or permit the shaft to both rotate and move longitudinally. An end cap 18 attached to the end of the shaft 16 prevents the shaft from being pulled through the journal box bore 14 .
Integral with and depending from one side of the journal box's base member 8 is a rigid flattened and elongated member that can be characterized as the upright stem 20 of the letter “C.” The base member 8 , the stem 20 and an integral, laterally extending platform 22 , that is parallel with the base member 8 , constitutes the frame of a “C” clamp. The operative mechanism that cooperates with the “C” shaped frame includes a threaded screw 24 that threadingly engages an aperture 26 in the laterally extending platform 22 . The screw is provided with a bearing pad 28 on the inner end thereof and a head 30 on the outer end thereof. A handle 34 , or finger tab, is functionally attached to the outer end of the screw, preferably utilizing the head 30 to fit into a channel shaped handle member, as shown in FIGS. 1 and 2.
The generally “C” shaped frame of the clamp 6 is specifically designed to fit over at least a portion of the flat bent over upper extremity 41 of the side 42 of the bed of a pick-up truck and around the down turned inside edge 40 thereof. The threaded clamping screw 24 and the cushioning pad 28 are adapted to operatively engage the underside of the flat bent over upper extremity 41 when the screw is tightened. The clamping action provided by the combination of the base member engaging the top surface of the bent over edge 40 and the screw contacting the underside of the bent over edge secures the journal box to the upper edge of the truck bed.
The shaft 16 is shaped to accommodate the type of load to be anchored. The shaft 16 of the embodiment of FIGS. 1 and 2 includes an end portion that is bent 90° to the axis of the shaft. This transverse “L” shape accommodates the attachment of a rubber grommet 47 that serves as the base for a strap 48 and a buckle 49 . The strap 48 encircles the crank arm 50 of a bicycle pedal assembly to tightly secure the bicycle that is standing on the floor of the truck bed against the inside of the side of the truck bed. If more than one anchor point is desired, another anchor of the same type may be used to tie down one of the frame members of the bicycle. Depending on the size, shape and design of the bicycle, it may be necessary or convenient for the combination of the grommet 47 and strap 48 to be closer to or farther away from the down turned upper edge of the bed side. By loosening the screws 12 and relieving the sandwiching pressure on the shaft 16 , the shaft may be rotated or moved longitudinally to position it and the lateral end thereof in a position of maximum convenience for wrapping the strap 48 around structural member of the load.
FIGS. 3 and 4 disclose an anchor 2 a similar to that of FIGS. 1 and 2 except that the shaft 16 a is straight instead of having a bent end portion. The straight shaft is advantageous for attaching the pivotal members of the cargo carrying rack, such as that that might support a boat or similar load over the bed of a pick-up truck. In the illustration of FIG. 4 two bracing members 51 and 52 of a rack are shown pivotally mounted on the inner ends of the shaft 16 a of two spaced apart anchors 2 of the present invention. Each of the anchors is clamped to the flat bent over upper extremity 41 of the side 42 of the bed of a pick-up truck. Each of the separate shafts 16 a of the two anchors 2 a can be adjusted by the journal box screws 12 to be non-rotatable or rotatable, depending on the operative nature of the braces or rack members that are attached to it.
FIG. 5 illustrates a third embodiment of the clamp 2 b that utilizes a “D” ring 58 to hold a strap, rope, belt or other kind of load securing tie. In this embodiment the longitudinal axis of the transverse bore 14 b is oriented ninety degrees from the position of the bore on the other described embodiments. The respective diameters of the bore 14 b and the stem of the “D” ring 58 are such that the stem of the ring is freely rotatable within the bore when the journal-adjusting screws 12 are tightened. This freedom of rotation allows the “D” ring to move in response to the necessary direction of the tie strap which is dependent on the location and size of the load.
There may be instances where it is not possible to engage the turned down inside edge of the flat upper extremity of the side of the truck bed with a “C” clamp type of clamping device 6 , as shown in FIGS. 1-5. Such an impediment would occur with the use of a full bed liner that follows the sides of the truck bed upwardly from the surface of the bed and projects outwardly to cover at least a portion of the flat upper extremity 41 . Such a bed liner would prohibit the entry of a “C” clamp type of device around the upper edge structure to which the clamp is to be secured.
FIG. 6 describes an alternative embodiment of the clamping device that overcomes the problem of inaccessibility of a “C” clamp. This embodiment avoids the necessity of making holes in the flat upper extremity 41 by providing a means for attaching the journal box directly to the outwardly turned edge of the bed liner 60 . In this alternative embodiment, the base member 8 c of the journal box does not require the mass associated with the base member being part of the “C” clamp, as in the embodiment of FIGS. 1-5. As in the preferred embodiment, the cleat 10 is superimposed over the base member 8 c and is provided with a transverse bore 14 c which, with the base member 8 c , journals a shaft 16 , or a “D” ring, similarly to the other embodiments. A pair of fastening and pressure adjusting screws 63 penetrate the cleat 10 , the base member 8 c , the bed liner 60 and threadingly engage a pair of nuts 65 attached to a clamping plate 67 . The clamping plate is positioned on the underside of the outwardly turned edge of the bed liner. Thus, by tightening the adjusting screws 63 the anchor 2 c will be secured to the rigid bed liner structure. In this alternative embodiment of the clamping structure, the shaft or “D” ring choices are the same as those for the “C” clamping embodiment. A rubber or felt pad 69 is preferably positioned between the clamping plate 67 and the flat upper extremity 41 of the side of the truck bed in order to insulate the paint on the truck bed from being damaged by contact with the clamping plate 67 .
FIGS. 8-12 illustrate a further embodiment 80 of the inventive anchor clamp. This version is especially useful where the top 41 of the side 42 of the truck bed comprises spaced apart upper and lower levels of sheet metal. With such a construction, a clamp of the type shown in FIGS. 1-5 tends to crush the box formed by the two layers of sheet metal, forming a dent in the top 41 of the truck bed side 42 .
To eliminate the crushing tendency, while at the same time providing a clamping force that contains both side and vertically directed force vectors to restrain the load, the threaded stem 82 of the anchor clamp 80 is directed into the corner bend 84 of the sheet metal forming the down-turned inside edge 40 of the truck bed side 42 . Preferably, the distal end of the stem 82 is fitted with a pad 86 that, at least to some extent, can conform to the shape of the inside corner against which it presses. If the inside shape of the corner is curved, then such a pad would preferably comprise a curved outer surface, such as contained in a cylinder 86 shown in FIGS. 8-12. If the inside corner is prone to more of a right angle, then a triangular shaped pad (not shown) is preferred.
Inasmuch as the outside corner 88 of the bend between the side-forming sheet metal 40 and the top edge 41 of the truck bed defines a right angle, the inside corner 90 of the clamp frame 92 is preferably also a substantially conforming right angle. Extending outwardly from the inside corner 90 and covering a substantial portion of the inside surfaces of the side wall 94 and the upper leg 96 is an optional pad 115 of rubber, felt or similar material that will protect the outside surface of the top 41 and the side 40 .
The body of the clamp of this embodiment is similar to the body of the clamps illustrated in FIGS. 1-5 to the extent that the body 92 comprises a frame, generally defining a “C” shape. Such a frame includes an upright portion, or a side wall 94 , having first and second spaced apart unilaterally projecting legs 96 and 98 . The upper leg 96 has previously, in the FIGS. 1-5 embodiments, been referred to as the base member 8 . The upper leg 96 has the same function and purpose as the base member 8 of the earlier embodiments insofar as serving as the foundation for the fastening cleat 10 . However, because the leg 96 does not co-act with the threaded clamping stem in the same way as does the base member 8 , the leg 96 is described as a distinct element related to this embodiment of the clamp.
In order to achieve the corner directed clamping action that is the object of this embodiment of the invention, it is necessary that the pad 86 on the tip of the threaded clamping stem 82 is directed toward the corner 90 of the clamp frame 92 . This requires angulation of the threaded clamping stem 82 . There are several ways in which the angular orientation of the stem 82 may be achieved. Where a lower projection of the frame is substantially perpendicular to the side wall, as the platform 22 is in the FIG. 5 embodiment, it is necessary to create an angularly oriented threaded bore in the platform to mount an angularly disposed threaded clamping stem. However, a simpler and structurally superior frame is produced by forming the lower projecting leg at an angle to the side wall, such as the projection 98 shown in FIGS. 8-12. Depending on the length of the side wall, but assuming proportions of the frame components as shown in FIGS. 9 and 10, an acute angle of approximately 75° between the leg 98 and the side wall 94 will provide a satisfactory orientation for the stem 82 , provided that the stem is disposed 90° to the plane of the projecting leg 98 . With this respective orientation the stem 82 is threaded through a perpendicular bore in the leg 98 in the same way as the threaded screw 24 engages the platform 22 in the FIG. 5 embodiment.
However, if the stem is limited to only longitudinal movement within a fixed position bore in the projecting leg, it is sometimes difficult to fit the anchor clamp around the down-turned edge of the top 41 of the truck bed side. Accordingly, the present embodiment provides for pivotal movement of the clamping stem 82 in order to get it out of the way during installation. Furthermore, the pivotal movement of the stem provides a means for self centering of the tip of the stem into a secure position in the bent corner of the truck bed's sheet metal structure. Pivotal movement of the stem 82 is achieved by threading the stem 82 through a bore in a cylinder 102 that is rotatably mounted in the lower projecting leg 98 . In the design shown in FIGS. 9 and 10 it is necessary to provide a relieved portion 103 in the leg 98 beneath the cylinder 102 in order to provide clearance for the lower portion of the stem 82 as it is pivoted. Of course, the cylinder 102 could be large enough to span the width of the projecting leg 98 and the relieved, or cut-out portion 103 , would be unnecessary in such case.
Instead of mounting a cleat 10 on the top of the projecting leg 96 , it may be desirable to form the cleat 110 integrally with the projecting leg 96 a , and the side wall portion 94 , as shown in FIGS. 11 and 12. Such a construction eliminates the need for a separate cleat member. The cylindrical shaft 116 that supports the grommet 47 may be threaded into a transverse bore in the integral cleat 110 and the top of the projecting leg 96 , as shown in FIG. 12 . Alternatively, an unthreaded shaft can be slidably inserted into an unthreaded transverse bore in the integral cleat and the projecting leg, similar to the way in which the shaft 16 is mounted on the clamp of FIGS. 1-5.
Whether the shaft securing cleat is of the integral or separate type, the angularly disposed clamping stem that provides clamping pressure in the corner of the structure on which the clamp takes its bearing provides a secure base for the anchoring mechanism. In all of the embodiments of the invention the ultimate anchoring mechanism may be the shafts 16 and 116 or the “D” ring 58 or other equivalent type of connection to a load that is to be anchored. In addition, as with traditional “C” clamps, the “C” clamps of FIGS. 1-5, and the corner clamp of the present invention, the use of the clamp is not confined to the bed of a truck, but may be applied wherever its structure and function are advantageous. | A cargo anchor primarily intended for attachment to the upper edge of the side of an open bed truck, comprising a journal box and an integral clamping apparatus. The journal box comprises a base member, a cleat superimposed on the base member and screws for interconnecting the cleat to the base member. A transverse bore in at least one of either the base member or the cleat is disposed parallel to the planes of the base member and the cleat and is sized to carry a shaft or a “D” ring that functions to support load binding straps or ties. Integral with the journal box is a clamping device for attaching the journal box to a flat structural member. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a flexible pipe capable of being used for transporting fluids such as hydrocarbons for example.
Several types of flexible pipe are used. Some flexible pipes comprise, from the inside outwards, an internal sealing sheath made of plastic, elastomer or some other relatively flexible appropriate material; an unsealed flexible metal tube which has to withstand the loads developed by the pressure of the fluid flowing along the pipe; one or more plies of armours and at least one external sealing sheath made of a polymeric material. This type of flexible pipe is often termed a "smooth-bore" by specialists in this subject.
Other flexible pipes termed "rough-bore" comprise, from the inside outwards, an unsealed metal tube known as the carcass, consisting of a section wound into interlocked turns such as, for example, an interlocked metal strip or wire of an interlocking shape such as a wire in the shape of a T, U, S or Z, an internal sealing sheath made of a polymeric material, one or more plies of armours capable of withstanding the forces developed by the pressure of the fluid flowing through the pipe and the external forces to which the flexible pipe is subjected, and at least one external protective sheath of the polymeric type.
In the latter type of flexible pipe, the internal sealing sheath is directly extruded, continuously, over the carcass which, between the wound turns, has spaces or gaps.
To ensure good contact between the internal sealing sheath and the metal carcass, it is necessary for the inside diameter of the internal sealing sheath to be as close as possible and even equal to the outside diameter of the flexible metal carcass.
When manufacturing a flexible pipe of the "rough-bore" type, the internal sealing sheath which is extruded over the metal carcass shrinks onto the latter as it cools. Depending on the materials used to produce the internal sealing sheath, deformations known as "shrinkage cavities" appearing on the internal face of the said internal sealing sheath and particularly on each side of the gaps between the turns of the metal carcass can be observed after cooling. Such shrinkage cavities are due, it would seem, to the differential shrinkage of the material used for the internal sealing sheath, because of the variation in cooling gradient through the thickness of the internal sealing sheath, combined with the effect of the gaps between the turns of the metal carcass. What actually happens is that since the extruded plastic sealing sheath is in contact via its internal face with the metal carcass which is at ambient temperature, the cooling of the said internal face is very quick, and this causes surface irregularities or shrinkage cavities; this phenomenon is amplified at the gaps between the turns of the metal carcass, the differential shrinkage at these points leading to local variations in the thickness of the internal sealing sheath. When the sealing sheath is made of semicrystalline polymer, sensitive to the presence of surface defects leading to a deterioration in the sheath which may go so far as to rupture it, such as for example PVDF, this very often, in operation, leads to degradation of the sealing sheath (rupture) so that it then no longer fulfils its sealing function.
In order to remedy a drawback of this nature and to solve the problem which arises through the appearance of shrinkage cavities, the solution of depositing a thin sacrificial sublayer of an appropriate material such as PVDF between the metal carcass and the internal sealing layer was found and adopted. The internal sealing sheath is then extruded over the said sacrificial sublayer but making sure that there is no "welding" or intimate bonding between the sealing sheath and the "sacrificial" sublayer, so that cracks propagating from the internal face of the sublayer outwards are stopped at the interface between the sealing sheath and the sacrificial sublayer. This is what is described in WO 95/24578.
The major disadvantage of this solution is the slippage that is likely to occur between the internal sealing sheath and the sacrificial sublayer at the ends of the flexible pipe, and the additional cost in raw material and in transformation (manufacturing) caused by the presence of the said sacrificial sublayer.
It is also possible to produce a sacrificial sublayer in the form of a thin tape (maximum 2 mm thick) obtained from a homopolymer or a copolymer. Naturally, the extruded sheath, also known as the pressure sheath, and the sacrificial sublayer, in the form of a film or tape, exhibit deformation at the gaps and this allows the assembly consisting of the sheath and the sacrificial sublayer to catch on the interlocked metal strip of the internal carcass, the deformation not being sufficient to create shrinkage cavities on each side of each gap, because of the thermal conditions generated in the volume thus created.
Other solutions for eliminating the appearance of shrinkage cavities or for lessening their effects have been sought.
Among these last solutions, the purpose of which is to install an internal sealing sheath which, after cooling, has a smooth and cylindrical internal face, employ shaping which is either internal, with the main drawback that it creates longitudinal cracks on the internal face of the sealing sheath and folds of material on the external face, or external with the drawback of a complete absence of anchorage of the sealing sheath to the metal carcass.
In the technique for manufacturing flexible pipes of the "smooth-bore" type, which consists in producing separately the internal sealing sheath, using any appropriate means such as extrusion, and the metal carcass, it has been recommended that the sealing sheath or the metal carcass be heated once the two elements have been assembled, so as to keep the sealing sheath plastic or render it plastic in order to force it to creep into the gaps between the turns of the metal carcass. Such manufacturing methods are described in particular in FR-B-74 14 398 (COFLEXIP) and addition No. 71 16 880 (IFP).
However, the sole purpose of these methods is to cause permanent creep of the polymeric sealing sheath between the turns of the metal carcass after or at the same time as stresses are developed in the internal sealing sheath so as to bring about intimate contact, the stresses developed being due, for example, to a pressurizing of the said internal sealing sheath.
In an exemplary embodiment described in patent FR-B-74 14 398 and which relates to a flexible pipe comprising a peripheral sheath extruded over an assembly comprising, from the inside outwards, an internal sealing sheath, a pressure arch, two plies of armours and a metal lattice, it is recommended that the assembly be heated prior to extruding the peripheral sheath so as to keep at least the internal face of the said peripheral sheath in the plastic state or, more precisely, in the thermoplastic state so as, and this is the desired objective, to cause the internal face to creep into the meshes of the metal lattice to completely fill them and thus completely attach the peripheral sheath to the metal lattice. Under these conditions, it is essential that the assembly be heated strongly to temperatures of the order of several hundred degrees Celsius. Such techniques have yielded such poor results that they were very soon abandoned because the filling both of the spaces in the pressure arch and of the meshes of the metal lattice rigidified the pipe and therefore reduced the essential property of flexibility which it is imperative that it exhibit.
U.S. Pat. No. 3,311,133 describes a pipe comprising an internal metal carcass consisting of an interlocked S-shaped metal strip, in the gaps of which is inserted a compressible rod. The pursued objective is to control the spacing between the turns of the metal strip while at the same time ensuring that the said carcass has a certain flexibility. The rod recommended in this patent is made of a material which is dense although compressible and which has mechanical and plastic properties which are such that it cannot be used in the specific application of the present invention and which will be described later on. A disadvantage of the compressible rod of the prior art is that it is unable to take up the tensile load when being fitted between the turns of the internal metal carcass.
In French application 96 10 490 filed by the applicant company, it is recommended that the metal carcass be heated to a temperature of below 100° C. upstream of the extrusion means so as to avoid sudden cooling of the internal face of the sealing sheath as it is extruded over the metal carcass. Work carried out on flexible pipes with preheated carcasses have demonstrated that the heat-induced creep of the internal sealing sheath was increased and that this sometimes caused the metal strip to lock. Such locking has the result of shifting the neutral axis in bending and therefore of increasing the deformation of the internal sealing sheath or pressure sheath on the outside of the bend. Now, when the complete flexible pipe is curved to the MBR (minimum bending radius) and if the strip is locked, it is easy to understand that for a deformation of the pressure sheath of the order of 6% on the outside of the bend, there is a deformation of practically about 10 to 12% on the inside of the bend, which is unacceptable. Furthermore, thermoplastics exhibit elongation at the threshold which reduces as the temperature decreases, which means that their capacity for deformation is also reduced at low temperatures. This phenomenon is of merely relative importance in the case of materials with a high elastic deformation, typically greater than 12% at the loading temperature, provided their capacity for deformation is maintained over time. By contrast, in the case of materials whose elastic deformation is limited, typically below 10 to 12% of the loading temperature, rupture may occur because this capacity for deformation is exceeded.
The use of thermoplastics whose capacity for deformation is high (greater than 10%) has not yielded good results because known thermoplastics are unable to withstand temperatures higher than 130 to 150° C. (homopolymers or copolymers of PVDF) or exhibit other disadvantages such as poor creep strength (PFA). This is why, for an effluent temperature of about 130° C., use is made of plasticized PVDF homopolymer. However, the plasticizer gradually disappears over time and this leads to an unplasticized thermoplastic which is unable to withstand the thermal and mechanical loadings. The loss of plasticizer is also a problem in that part of the pipe which is housed in the end fitting.
Furthermore, industrial implementation of a heated carcass and subsequent extrusion of the internal sealing sheath poses real problems. This is because the temperature-induced creep into the gaps varies according to the viscosity of the plastic used for the internal sealing sheath and the temperature to which the metal carcass is heated. As the physico-chemical properties of the said plastic may vary from one batch to another, it is practically impossible to have control over the temperature-induced creep under normal conditions of industrial implementation; complete temperature-induced creep has often been observed, that is to say complete filling of the gaps. It is easy to understand that complete temperature-induced creep may lead to locking of the metal carcass and therefore to reduced pipe flexibility. For example, when the filling of the gap by the internal sealing sheath is more than 90%, there is a risk that the flexible pipe will lock up at certain points.
SUMMARY OF THE INVENTION
The object of the present invention is to overcome the aforementioned disadvantages and to propose a flexible pipe in which at least the internal sealing sheath is made of thermoplastics which alone or in combination exhibit significant temperature-induced creep and viscoelastic elongation of below 10-12% throughout the range of temperatures which lie between the service limits, and without forming shrinkage cavities.
To achieve this, the effects of heating the carcass so as to avoid the formation of shrinkage cavities as explained in the application studied earlier and filed in the name of the applicant company is combined with a limitation of the temperature-induced creep of the internal sealing sheath into the gaps between the turns of the carcass so as not to lock up the movement of the metal strip that forms the said carcass, while at the same time obtaining positive catching of the internal sealing sheath on the said carcass, the said catching being a result of the limited temperature-induced creep into the gaps.
One subject of the present invention is a method for manufacturing a flexible pipe for transporting fluids such as hydrocarbons, of the type comprising, from the inside outwards, a flexible metal carcass with a helical winding of non-contiguous turns, a compressible rod fitted into the gap between the consecutive turns of the helical winding, an internal sealing sheath extruded over the metal carcass, at least one ply of armours wound around the internal sealing sheath and at least one external sealing sheath arranged around the ply of armours, and the pipe is characterized in that the compressible rod has a substantial volumetric deformation in compression of at least 50%.
The fact of using a rod which is highly compressible, particularly under a low strain load, allows temperature-induced creep to occur as the internal sealing sheath is being extruded over the metal carcass, while at the same time restricting the penetration to a predetermined value.
According to one feature, the metal carcass is heated prior to the extrusion of the sealing sheath, and this makes temperature-induced creep easier while at the same time avoiding the formation of shrinkage cavities.
According to another feature, the rod is made of a cellular material comprising between 40 and 60% by volume of hollow cells and having a first elastic modulus E 1 of the cellular part and a second elastic modulus E 2 of the dense part, the ratio of the two moduli E 1 /E 2 being at least higher than 10.
According to another feature, the rod consists of a hollow tube which may preferably be made of a dense material or may be made of a cellular material.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages will emerge more clearly from reading the description of a preferred embodiment of the invention, and from the appended figures in which:
FIG. 1 is a partial perspective view with cutaway of a flexible pipe,
FIG. 2 is a diagrammatic and partial view of part of the metal carcass coated with part of an internal sealing sheath according to the present invention,
FIG. 3 depicts a curve of stress in N/linear mm as a function of displacement in percent.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The flexible pipe 1 according to the invention is of the type comprising, from the inside outwards:
a metal carcass 2 produced by a helical winding of a metal wire with non-contiguous turns 3 and a predetermined cross section, for example with an S-shaped cross section as in the example depicted in FIG. 2,
an internal sealing sheath 4 arranged by extrusion around the metal carcass 2,
a pressure arch 5,
one or more plies of armour 6,
possibly an intermediate strip 7, and
an external sealing sheath 8.
The external sealing sheath 8 may also be extruded over the intermediate strip 7 if there is one or over the outer ply of armour 6. The internal sealing sheath 4 and external sealing sheath 8 are made of a common plastic or of different plastics, according to the requirements and end use of the flexible pipe 1.
As the metal carcass has non-contiguous turns 3, a space or gap 9 is formed between two consecutive turns 3. The helical winding of the carcass has an S-shaped cross-section, including one arm of the winding at each turn of the winding being outward of one arm of the S in the neighboring turn of the winding at one lateral side of the turn and being inward of the one arm of the S in the neighboring turn of the winding at the opposite lateral side of the turn, and the S-shapes of the turns being so shaped and located as to define the gap between the part of the S-shape connecting the arms of the S. During or after the manufacture of the metal carcass 2, a compressible rod 10 is fitted into the gaps 9 (FIG. 2). The compressible rod 10 may, depending on the stage of manufacture during which it is inserted into the gaps, be positioned in the bottoms of these gaps or at a certain height up from the bottom of the gaps. In any event, the rod is positioned in such a way that at most 75% of the volume of each gap may be filled by the substance of the internal sealing sheath 4 as, the said substance comes to press on the compressible rod. Of course, the geometry of the compressible rod is adapted to suit the shape of the gap; in a preferred embodiment of the invention, the cross section of the said compressible rod has a cross-sectional area at least equal to 25% of the right cross-sectional area of the gap at the mean pitch of the interlocked metal strip used for manufacturing the metal carcass so as to ensure, as specified earlier, that at most 75% of the volume is available for the temperature-induced creep of the internal sealing sheath.
In a first embodiment, the compressible rod is manufactured from a material which has to exhibit certain properties and, in particular, has to:
have a volumetric compression ratio of at least equal to 50% and is chosen from the family of hydrocarbon elastomers and, preferably, from the family of silicon-containing or silico-fluorinated elastomers,
be able to withstand, for at least five minutes, the temperature to which the internal sealing sheath is heated while it is being extruded over the metal carcass.
According to a preferred embodiment of the invention, the compressible rod is made of a cellular material which has a high volumetric compressibility under light load. The dense substance of the rod occupies a volume of between 40 and 60% of the total volume of the rod. With reference to FIG. 3 which, on the one hand, depicts a first curve C 1 (left-hand part) representing the stress in Newtons per linear millimeter and, on the other hand, a second curve C 2 depicting the elastic spring-back after compression, it may be seen that the material has a first elastic modulus E 1 relating to the hollow part of the said material and a second elastic modulus E 2 relating to the dense part of the same material. The modulus E 1 is determined by the straight line D 1 which is tangential to the curve C 1 for the abscise value of approximately 40%, whereas the elastic modulus E 2 is determined by the straight line D' 1 which is tangential to the curve C 1 for the abscise value of approximately 75%. The ratio E 1 /E 2 is in any event higher than 10 and preferably higher than 30. From curve C 1 , it may be seen that for a volumetric (or compressive) displacement of the rod by 50%, the stress that has to be applied in order to obtain such a displacement is 0.4 N/linear mm and that for 65% displacement the stress is of the order of 1.3 N/linear mm, the total compression of the cellular part of the rod corresponding to a displacement of 80% for a stress of 4 N/linear mm. Curve C 2 shows that the material tested had an elastic spring-back of at least 60%, that is to say that the material, when compression ceases, practically returns to its initial shape and volume. In any event, the volumetric compressibility is high for low stress below 1 Newton per linear millimeter for a 60% displacement of the substance of the said rod.
In a second embodiment, the compressible rod is produced in the form of a hollow tube 10', preferably of round cross section. The outside and inside diameters of the hollow tube are chosen, according to the nature of the material used to manufacture the said hollow tube, so that the volume occupied by the said rod in the compressed state is at most equal to half the volume occupied by the said rod in the uncompressed state. A preferred material for the manufacture of the rod is a silicon-containing or hydrocarbon elastomer with a shore A hardness of between 65 and 85.
The outside diameter of the hollow tube is of the order of 0.6 to 0.7 times the depth of the gap or free height of the carcass. For a metal strip of dimensions 48×1.2 mm used to make the carcass, the diameter will be 0.6×4×1.2=2.88 mm, for a strip measuring 40×0.8 mm, the diameter is preferably 0.7×4×0.8=2.24 mm.
The wall thickness of the hollow tube is from 0.1 to 0.25 and preferably from 0.12 to 0.15 times the diameter of the said hollow tube.
In order to allow it to take up the tensile load needed for fitting it into the gaps 9 in the metal carcass, at least one strengthener 11 is either embedded in the mass of the compressible rod 10 when the material used is a cellular material, or preferably arranged in the hollow part of the tube which forms the rod. In both instances, the strengthener is unidirectional and made of an inorganic, organic or vegetable substance. The unidirectional strengthener also provides the rod with a certain longitudinal stiffness so that the ratio Δ1/1 is roughly near to zero, and this makes it even easier for it to be fitted into the gaps and makes it better at taking up the tensile load to which it may be subjected as it is fitted in the gaps of the metal strip; this thus avoids the variation (reduction) in cross section of the rod and allows the rod to maintain, in the gaps, the degree of compaction which it initially had (40 to 60%) prior to being fitted. In the case of the hollow tube, the strengthener 11 is preferably arranged at the center of the tube, although the positioning may be different. Likewise, it is possible to house the strengthener 11 in the substance of which the tube is made at any point whatsoever.
Of course, if the tensile load is relatively light during fitting into the gaps, it is then possible not to use a strengthener in the rod.
One method of manufacturing the flexible pipe described hereinabove consists in interposing the compressible rod while the metal carcass 2 is under axial tension and before the plastic sheath 4 is extruded over the said metal carcass. Axially tensioning the metal carcass has the result of allowing the gap 9 to be at its widest, so that the rod can easily be housed in the open gaps. When the axial tension is released, the dimensions of the gaps reduce, and this allows the compressible rod to be held in the appropriate position so as to limit the creep of the sheath 4 into the gaps.
All shapes or cross sections of rod such as round, triangular, rectangular, are possible, provided that, in all cases, they are compatible with the cross section of the carcass gap in which the rod is fitted.
The use of a rod in the form of a hollow tube instead of a solid cellular rod allows better adaptation to suit the dimensions of the gap. This is because when the gap is relatively large, the rod occupies the gap while being widely open. When the gap is not so wide, that is to say when two consecutive turns of the carcass are closer together, the rod deforms in the heightwise direction of the gap as the walls of the rod move closer together, thus making the rod more closed. For an even smaller gap width, the rod may be flattened, with the walls in contact with each other and compressed by the turns of the carcass. Thus, whatever the configuration of the carcass, the hollow tube which forms the rod can be used, because it better adapts to suit the dimensions of the gaps. | Flexible pipe for transporting fluids, comprising, from the inside outwards, a flexible metal carcass with a helical winding of non-contiguous turns, a compressible rod fitted into the gap between the consecutive turns of the helical winding, the compressible rod has a substantial volumetric deformation in compression of at least 50%, an internal sealing sheath extruded over the said metal carcass, at least one ply of armours wound around the said internal sealing sheath and at least one external sealing sheath arranged around the said ply of armours, the rod, its materials, its elastic modules and other features thereof are disclosed. | 5 |
This is a continuation of application Ser. No. 07/864,545 filed Apr. 7, 1992, now U.S. Pat. No. 5,306,796.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a pliable crystalline polymer and to a process for its production.
2. Background of the Related Art
Imparting pliability to crystalline polymers especially with a view to permitting the production of articles demanding a certain pliability is generally obtained by an action involving chemistry: action on the degree of short branching or mixing with elastomers or with plasticisers. However, such processes are found to be tricky and costly. Thus, for example, in the polyethylene field, a variety called "VLDPE" is currently produced, which is undoubtedly characterised by a remarkable pliability, but whose cost of manufacture is high.
SUMMARY OF THE INVENTION
It has now been found that it is possible to impart pliability to crystalline polymers solely by physical means, namely, by orienting these polymers under determined conditions which will be specified below.
The present invention consequently relates chiefly to an oriented crystalline polymer which is pliable in the absence of any adjuvant, characterised in that it exhibits a tensile modulus E, measured in the drawing direction, of between 0.3 and 0.8 E 0 , E 0 being the tensile modulus of the same polymer, unoriented.
The oriented and pliable crystalline polymer in accordance with the invention is all the more surprising since it is known that a molecular orientation is reputed to make polymers more rigid.
The oriented and pliable crystalline polymer according to the invention may be of any nature, but it is generally preferred that it should be produced from at least one olefin.
A polymer produced from at least one olefin is intended to denote olefin homopolymers such as especially polyethylene or polypropylene and copolymers containing at least 50% by weight of olefin-derived units.
The oriented and pliable crystalline polymer in accordance with the invention is particularly suited for the production of elongate articles such as reeds, fibres, fills, filaments and the like, which must exhibit good pliability.
The invention also relates to a simple and economical process for producing such an oriented and pliable crystalline polymer.
According to the invention such an oriented and pliable crystalline polymer is obtained by drawing the extruded polymer
to a deformation ratio higher than 500%,
at a temperature of between T m +10° C. and T m +30° C., T m being the melting temperature of the polymer, and
at a mean velocity gradient ε of between 1/20τ and 10/τ, τ being the mean relaxation time of the polymer at the chosen extrusion temperature, and
by cooling the drawn polymer directly to a temperature below its crystallisation temperature in a time of less than 10 seconds.
The relaxation time of the polymer is defined by the relationship: ##EQU1## in which: η 0 is the viscosity of the polymer at velocity gradients tending towards 0,
ρ is the density of the polymer,
M c is the critical molecular mass above which η 0 (in the case of monodisperse polymer) is proportional to the power 3.4 of the molecular mass,
R and T are the gas constant and the temperature.
In the process in accordance with the invention the polymer must be preferably extruded at a temperature exceeding its melting temperature by approximately 20° C. If need be, a heat exchanger may be placed at the exit of the extruder to bring the polymer to this temperature.
The drawing of the crystalline polymer may be carried out in the extrusion die or by passing the extrudate between two successive and closely adjoining pairs of rolls rotating at different speeds, this being a matter of choice. The Applicant Company generally prefers that the deformation ratio during this drawing should be markedly higher than 500% and even higher than 1000%.
In the process according to the invention the drawn polymer may be cooled rapidly to a temperature below its crystallisation temperature by any conventional means of chilling, such as, for example, passing over a sudden-chill roll. It is preferred, however, that this cooling should be produced by continuous passing through a bath of water maintained at a temperature below 30° C. It is generally preferred that the chilling should be carried out in less than 5 seconds and preferably in less than 2 seconds.
According to another embodiment of the process according to the invention the polymer may be extruded in the form of a parison and, in this case, the drawing is obtained by blowing a gas into the parison.
By virtue of the process according to the invention it is especially possible to obtain elongate articles based on conventional low-density polyethylenes exhibiting a pliability which is analogous to similar articles produced from very low density polyethylenes (VLDPE) or from plasticised polyvinyl chloride.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The process according to the invention is, furthermore, clarified in greater detail in the examples of practical embodiment which are to follow and in which example 3R, given by way of comparison, is excluded from the scope of the present invention.
Example 1
A low density polyethylene (d=0.920) exhibiting a mean relaxation time of 0.02 s is extruded at a stock temperature of 140° C., by employing an extruder [D(diameter):30 mm, L(length)/D:25, compression ratio 3] equipped with a heat exchanger and a capillary die 2 mm in diameter, 2 cm in length and having an entry angle of 90°. The extrusion speed is 10 m/min, the mean velocity gradient in the convergent entry has a value of 30 s -1 and the deformation ratio is 20. The reed thus extruded is then passed through a water bath at 15° C. situated approximately 5 cm from the die exit.
The product thus obtained has a secant tensile modulus at 2% deformation which is 70 MPa (the modulus being measured on a reed 100 mm in length and at a traction speed of 10 mm/min).
By way of comparison, the tensile modulus measured under the same conditions on unoriented reeds drawn as melt (velocity gradient<1/200τ) and cooled slowly, obtained from the same polymer, is 150 MPa. It appears, therefore, that the oriented reed obtained according to the process of the invention has a tensile modulus reduced by approximately 50%.
Example 2
The procedure is as in Example 1, but with an extrusion temperature of 150° C. being chosen, and using a high density polyethylene (d=0.950) which has a relaxation time of 0.1 s, the extrustion speed being 3 m/min.
The product thus obtained has a tensile modulus, measured as in Example 1, of 440 MPa.
By way of comparison, the tensile modulus measured under the same conditions on unoriented reeds drawn as melt (velocity gradient<1/200τ) and cooled slowly, obtained from the same polymer, is, in contrast, 1000 MPa. It again appears that the oriented reed according to the process of the invention has a tensile modulus reduced by approximately 50%.
Example 3R
The procedure is as in Example 1, except that the extrusion speed is reduced to 10 cm/min so as to impose a velocity gradient of 0.3 s -1 , situated outside the claimed region.
The product thus obtained has a tensile modulus, measured as in Example 1, which is 140 MPa. It appears, therefore, that this product exhibits a modulus comparable to that of an unoriented product (cf. Example 1).
Example 4
The procedure is as in Example 1, except that the distance separating the die from the entry of the cooling bath is increased to 100 cm (cooling time>5 s). The tensile modulus of the reed obtained, measured as in Example 1, is in this case 110 MPa. It is therefore concluded that the product thus obtained, while satisfactory, is less pliable than that obtained according to Example 1. This example consequently shows the advantage of a rapid chilling of the drawn product.
Example 5
The polymer of Example 1 is processed on an extruder (D: 45, L/D: 20, compression ratio 3) equipped with a flat die [g (gap): 4 mm] maintained at 140° C. The deformation velocities in the die are negligible and the film thus produced is very weakly oriented on leaving the die. This film, extruded at a speed of 1 m/min, is then highly drawn between two pairs of press rolls over a distance of 10 cm (mean velocity gradient=5 s -1 ). As it leaves the second pair of rolls, the film is driven at a speed of 20 m/min and has a thickness of 0.5 mm. The film is then immersed directly in a water bath similar to that employed according to Example 1.
The tensile modulus of this film, measured on a specimen according to DIN standard 53457, under the conditions of Example 1, is 90 MPa.
The tensile modulus measured under the same conditions on a specimen cut from a film extruded at 200° C. from the same polymer, drawn as melt at a velocity gradient<1/200 and cooled slowly in air, is 190 MPa. It is once again concluded, therefore, that the film produced according to the process of the invention has a tensile modulus reduced by approximately 50%. | An oriented crystalline polymer includes a crystalline polymer which is oriented, preferably above its melting temperature, which is pliable in the absence of any plasticizing adjuvant, and which exhibits a tensile modulus E, measured in the drawing direction, of between 0.3 and 0.8 E 0 , E 0 being the tensile modulus of the same polymer, unoriented. | 1 |
CROSS REFERENCE TO PRIOR APPLICATION
[0001] This application is a continuation application filed under 35 U.S.C. §120 and claims priority to U.S. patent application Ser. No. 13/386,479, filed Jan. 23, 2012, which is a National Stage application of PCT/IB2010/053213, filed Jul. 14, 2010 and claims priority thereto under 35 U.S.C. §371 and 35 U.S.C. §365(c), which itself claims priority to European Application No. EP 09166296.5, filed on Jul. 24, 2009. The entireties of these disclosures are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a controllable lighting system.
BACKGROUND OF THE INVENTION
[0003] Lighting systems are widely used to create ambiance in homes. The systems create light patterns that create atmospheres.
[0004] WO 2009/031103 describes a multi color light source emitting light beams of different colors. The multi color light sources can be used in applications in which highly concentrated full spectrum light is required. Examples of such applications are spot lighting and digital projection. In this way the color of e.g. the spot lighting can be varied. But a problem with this arrangement is that in order to achieve a moving light pattern the light source needs to be moved by e.g. a mechanical arrangement. As a consequence of that, such systems are often not thin and compact but relatively thick and bulky.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to overcome these problems, and to provide a lighting system that can create a changeable lighting pattern and that is thin and compact.
[0006] This object is fulfilled by a lighting system comprising a plurality of controllable light emitting elements, a spreading optical element arranged in front of the plurality of light emitting elements to shape the light emitted from the lighting elements, and a controller for varying a light emission angle range of light emitted from the spreading optical element by controlling each of the plurality of controllable light emitting elements.
[0007] The spreading optical element defines an available angular emission range, within which all light emitted by the system will be contained. The control of the light emitting elements then effects a selection of an angular subrange of this available range. By controlling the selection of this subrange the resulting illumination pattern can be varied. This allows the light emitted from the spreading optical element to be varied without varying any physical parts of the lighting system, because the controller now controls each of the light emitting elements, by e.g. dimming one or more of the light emitting elements or by switching one or more of the light emitting elements off. In this way it is e.g. possible to scan light beams, change beam size and shape, since the spreading optical element can convert light emitted from a cluster of light emitting elements into one beam. By changing the position and/or size of the cluster of light emitting elements it is possible to change the location and/or size of the spots.
[0008] The emission angle range may further be divided into several separate sub-ranges, by activating several separate clusters of light emitting elements. The illumination pattern may thereby comprise several spots.
[0009] The controller may further be adapted to vary at least one of illumination gradient and color gradient of light emitted from the spreading optical element.
[0010] In an embodiment, the lighting system comprises a plurality of individually collimated light sources, each comprising a plurality of said controllable light emitting elements and a beam collimating optics. In this way a number of narrow beams are obtained. For example each collimated light source may include a red, a blue, and a green light emitting element. Thus it is possible to determine the color output of the light.
[0011] The plurality of the collimated light sources can e.g. be arranged in a two dimensional array. Accordingly it is e.g. possible to provide a spot that can be moved in two directions without any moving optical elements. E.g. the two dimensional array may be a rectangular N×M-array, where N represents the number of rows in the array, and M represents the number of collimated light sources in each row. E.g. N and M each are at least 6.
[0012] For example the controller may be programmed to realize a plurality of different light emission patterns by applying a set of preprogrammed control parameters of the controllable light emitting elements. In this way different ambiences can be created. The term light emission pattern should be construed as the light pattern made up of various properties of the light emitted from the spreading optical element e.g. emission angle ranges, colors, and illumination gradient, as well as the dynamics of the emitted light e.g. different pulse patterns.
[0013] The lighting system may further comprise a light sensor, such that in use the light sensor measures prescribed light emission angle ranges and the controller compares these with a requested light emission angle ranges. In this manner the light emission ranges can automatically be adjusted to a prescribed light emission range without any user assistance. For example the light sensor and the light emitting elements may be electrically and mechanically integrated in a lighting unit, so that a compact design is achieved. By use of a sensor it is possible to automatically adapt the light pattern, i.e. it is possible to adapt the light pattern without moving the lamp or by input to the lamp. This is an advantage since when a lamp is positioned in a home the position of the lamp may change once in a while unintentionally due to small movements and shifts, which for instance is a result of pushes against the lamp during cleaning, or intentionally. In this way it is e.g. possible to vary the beam angle, shift the beam angle, vary the gradient of illumination, and vary the gradient of color if colored red, green and blue LEDs are used. The lighting system may e.g. comprise an indicator adapted to transmit light information, and wherein the light sensor is adapted to sense the light information transmitted to the light sensor, and transmit this transmitted light information to the controller, the controller being adapted to link the transmitted light information into a light emission pattern. This provides for an easy use of the lighting system.
[0014] The spreading optical element may e.g. be a negative or positive lens, a negative or positive Fresnel lens, or a patterned array of micro-prismatic beam deflectors. It is an advantage of the Fresnel lens that it is thin and compact compared to a conventional lens, and besides that it is much easier to manufacture than a patterned array of micro-prismatic beam deflectors. If a positive lens or a positive Fresnel lens is used it provides for longer working distances in order for the light to spread after it has been focused.
[0015] It is noted that the invention relates to all possible combinations of features recited in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing a currently preferred embodiment of the invention. Like numbers refer to like features throughout the drawings.
[0017] FIG. 1 is a lamp according to an embodiment of the present invention.
[0018] FIG. 2 is a schematic view of a lamp with a negative lens.
[0019] FIG. 3 is a schematic view of a lamp with negative Fresnel lens.
[0020] FIG. 4A-4C are schematic views of a lamp with various beam shapes.
[0021] FIG. 5 is a schematic drawing of a lighting system according to an embodiment of the present invention.
[0022] FIG. 6 is a schematic view of an integrated lamp with sensors.
[0023] FIG. 7 is a schematic view of an integrated lamp with sensors and an indicator.
[0024] FIG. 8 is a flow chart of the functionality of a controller.
DETAILED DESCRIPTION OF EMBODIMENTS
[0025] The lighting unit in the illustrated example in form of a lamp 1 in FIG. 1 comprises an array of collimated light sources 2 arranged in a two dimensional array wherein the two dimensional array is a rectangular 16×16-array. The collimated light sources 2 , each comprises a plurality of the controllable light emitting elements 3 and a beam collimating optics 4 , wherein each collimated light source 2 includes a red, a blue, and a green light emitting element 3 , preferably in form of a red, a blue and a green Light Emitting Diode (LED) 3 . Alternatively each collimated light source 2 may include a red, a blue, a green and a white light emitting element 3 . The lamp 1 further comprises a negative lens 5 arranged on top of the collimated light sources 2 .
[0026] FIG. 2 shows a schematic view of a lamp with a negative lens 5 . A number of light emitting elements 3 may e.g. be mounted on a Printed Circuit Board (PCB) layer 22 . The PCB may e.g. comprise an isolated carrier made of a heat transferring material such as a metal, e.g. aluminum, with a single isolation layer. In the illustrated example the light emitting elements 3 are grouped in a red LED, a blue LED and a green LED, arranged with a beam collimating optics 4 in front of them, in this way an array of collimated light sources 2 is achieved. Alternatively the light emitting elements 3 could be grouped in a red LED, a blue LED, a green LED as well as a white LED, arranged with a beam collimating optics 4 in front of them. A spreading optical element in form of a negative lens 5 is arranged in front of the collimated light sources 2 and thus also the light emitting elements 3 . In the illustrated example all the collimated light sources 2 emit light such that the negative lens 5 spread emitted light 6 over the entire emission angle range.
[0027] FIG. 3 depicts a schematic view of a lamp with negative Fresnel lens 105 . Like in FIG. 2 a number of light emitting elements 3 are typically mounted on a PCB layer 22 , but the spreading optical element is in the presently illustrated example a negative Fresnel lens 105 . This has the advantage that the design of the lamp is very compact.
[0028] FIGS. 4A-4C show schematic side views of a lamp with various beam shapes. FIG. 4A shows a lamp that emits a light beam with a full emission angle range, and FIG. 4B and FIG. 4C show a lamp that emits a light beam within a subrange of the full emission angle range. The lamp is able to emit a beam within a subrange of the full emission angle range by emitting light from a cluster of collimated light sources 2 . In this way the size and the shape of the spot size of the beam can be varied by varying the number of collimated light sources 2 and the shape of the cluster. Consequently no mechanically moving parts are needed. In the illustrated example in FIG. 4B a beam is emitted from the spreading optical element by emitting light from the three collimated light sources in the middle of the lamp. In FIG. 4C a beam is emitted from the spreading optical element by emitting light from three collimated light sources 2 from the right side of the lamp. Changing between the two beams (in FIG. 4B and FIG. 4C ) results in that it is conceived as one beam that shifts between two positions.
[0029] The intensity of the LEDs may be changed gradually depending on the application, such as in 100 or in 256 steps, e.g. from an off-state to the desired intensity, e.g. a maximum intensity.
[0030] FIG. 5 is a schematic drawing of a lighting system according to an embodiment of the present invention, including a lamp 1 and a remote controller 107 . In the illustrated example the lamp 1 comprises an N×M array of red, green and blue LEDs sets 2 arranged with 8 bits resolution. Alternatively the LED sets could be arranged with a 10 bits resolution. Each of the LED sets 2 comprises a collimator 4 thereby providing N×M collimated light sources 2 . A spreading optical element in form of a negative Fresnel lens 105 is arranged in front of the N×M collimated light sources 2 , i.e. in front of the red, green and blue LEDs. In this way the light emitted from the LEDs can be shaped. The lamp 1 further comprises a controller 7 adapted to vary a light emission angle range of light emitted from the Fresnel lens 105 , by controlling each of the LEDs 3 . The controller 7 comprises a processor 10 and a memory 23 including a shift register 13 with a 3×N×M length and a Latch with a 3×N×M length. The controller 7 further comprises 3×N×M triple Pulse Width Modulation intensity controllers 12 .
[0031] The remote control unit 107 comprises a power supply 18 , a processing unit 19 in communication with a memory card 8 and a personal computer, and a wireless transmitter 9 . The remote control unit 107 is programmed to realize a plurality of different light patterns by applying a set of preprogrammed control parameters of the LEDs. The light patterns are stored on the memory card 8 . Each light pattern may be linked to an ambience prescription like “summer”, “cozy” or “cool”. That is, when one of the ambience prescriptions is chosen a corresponding light pattern is emitted by the lamp, such that e.g. a certain color distribution and beam size is emitted. These ambience prescriptions can be chosen by a user by input to the system e.g. via a personal computer 20 , which comprises control software. The drive signals for the N×M RGB-LED arrays are mapped by the processing unit 19 in the remote control unit 107 .
[0032] These drive signals are wirelessly transferred to the lamp 1 from a wireless transmitter 9 in the remote control unit 107 to a wireless receiver and serial interface in the processer 10 in the lamp 1 . In another embodiment of the invention the remote control unit 107 is able to communicate with multiple lamps
[0033] In the lamp 1 the signals are first stored in the Shift Register. When the transfer of the drive signals is completed, the information is copied into the Latch 11 and subsequently directed to the Triple Pulse Width Modulation intensity controller 12 drivers of the individual RGB-LEDs. After copying the drive signals to the Latch 11 , new drive signals can be received by the Shift Register 13 . An advantage of this lay-out is that it is not necessary to provide addressing contacts to all LEDs individually, but that internal storage in the Shift Register 13 and the Latch 11 greatly simplifies the connections to the remote control unit 107 . Another advantage is that the changes in drive signals and thus the lighting patterns occur at a well-defined moment and in a well-defined manner when the signals are transferred from the Shift Register 13 to the Latch 11 . This transfer happens very fast and reliably, compared to slow and error-prone wireless transfer. In this way the controller 7 is adapted to vary the emission angle range of light emitted from the spreading optical element, by controlling each of the LEDs 3 .
[0034] In an alternative embodiment of the invention the functionality of the remote controller 107 is integrated in the controller 7 .
[0035] FIG. 6 is a schematic view of an integrated lamp with at least one light sensor 14 . In the illustrated example the lamp is provided with a number of light sensors 14 providing feedback 15 to a processor 10 of the controller 7 . The light sensor 14 measures prescribed light emission angle ranges and the processor 10 compares the feedback 15 with requested light emission angle ranges 16 , e.g. received from a user. By input 21 from the processor 10 an LED controller 12 transmits the parameter setting to each collimated light source 2 .
[0036] The light sensor 14 is adapted to sense the light that has been emitted from the spreading optical element 5 , which in the illustrated example is a negative lens, and reflected back to the light sensors 14 . Preferably the light emitting elements 3 and the light sensors 14 are electrically and mechanically integrated in a lighting unit e.g. in form of a lamp.
[0037] In an embodiment of the invention the light sensors 14 are cameras having a wide angle lens so that the combination of the images of all the cameras will be larger than the maximum spot beam of the lamp. In this way the set of cameras will see the whole surface illuminated by the lamp. The images made by the cameras will be processed, in real time, by the controller 7 and based on the requested illumination pattern; the parameters will be set for each of the LED sets.
[0038] FIG. 7 shows a lighting system that comprises an indicator 24 , e.g. in form of a laser pointer, adapted to indicate a desired light pattern to the lighting system by emitting light 25 onto a surface 26 , to be reflected and then received by the light sensors 14 . The light emitted from the indicator may be coded, in order to enable the sensors 14 to distinguish it from other light. The light sensor 14 is adapted to detect the light information 25 , and transmit this light information to the controller 7 . The controller 7 is adapted to interpret the transmitted light information and to adapt the emitted light so as to provide the desired light pattern.
[0039] With the indicator 24 in FIG. 7 , a user is able to indicate to the lighting system 1 the shape of the beam to be presented on a surface 26 e.g. a wall. In order to do this, the user uses the indicator 24 to indicate on the surface 26 the area 27 that is to be illuminated. The light sensors 14 detect the light information 25 , i.e. the laser's reflection of the wall 26 , and use this information to adapt the emitted light pattern. Thus a new light pattern can be requested by the user at any moment in time. So, for instance the user may request to reshape a currently presented shape.
[0040] FIG. 8 is a flow diagram of the functionality of the controller 7 . The flow diagram illustrates the automatic process of adapting the light pattern, i.e. the emission of light from the lamp.
[0041] The controller comprises the following processing steps:
[0042] The lamp 1 creates a light pattern based on the requested light pattern, (in the first iteration) using the parameter settings stored from an earlier occasion, or (in the following iterations) using the adapted parameter settings;
[0043] Information from the light sensor(s) 14 is used as input to determine the differences between the requested light pattern and the measured light pattern;
[0044] The differences are used by the processor 10 to calculate new parameter settings;
[0045] The new parameter settings are compared to the parameter settings that are stored in memory. If the new parameter settings are different than the parameter settings calculated during the previous iteration, program control returns to step S 1 ;
[0046] If the new parameter settings are not different, the best possible presentation of the requested light pattern has been reached, and the process ends.
[0047] The steps S 2 and S 3 , as described in the process steps above, are the most important ones. In these steps it is determined where the mismatches between the requested light pattern and the measured light pattern are and what the new parameter settings have to be.
[0048] By extending the above described process it is possible to detect disturbances or inconsistencies in the light pattern on a wall, e.g. a corner in the wall or a plant in front of the wall, etc., and adjust the parameter setting and thereby the illumination, i.e. the light pattern.
[0049] Further extensions can be implemented. In another extension the angle that the lamp makes with the surface that is to be illuminated can be determined by scanning this surface, i.e. change the beam direction and measuring the light intensity picked up by the light sensors. The peak light intensity measured together with the direction of the light beam provides information about the angle the lamp makes with the surface to be illuminated.
[0050] In another embodiment of the invention the lamp comprises a tilt sensor or the extension as described above. In this way it is possible for the lamp to know the angle under which it emits light e.g. on a wall. This can be done by turning the LED sets on, which, via the spreading optical element (e.g. in form of a Fresnel lens), shine at the wall under an angle of 90 degrees, with fixed Lumen values. Reflections to the light sensor are used to calculate the reflectivity of the wall. This is useful if it is necessary to correct for the spreading optical element in front of the light sensor, e.g. in case a camera is used as a light sensor.
[0051] In a further embodiment further light sensors are arranged outside the lamp and the feedback could be a combination of the light sensors inside the lamp and the light sensors outside the lamp. In this way more feedback can be provided and consequently the calculations can be improved.
[0052] The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. For example, the number of light emitting elements and thus also light sources and the number of light sensors may be varied. Also the numbers, N, M, in the rectangular N×M array can be varied, it may e.g. be a 1×2 array or a 12×12 array. | A lighting system comprising a plurality of controllable light emitting elements is disclosed. The lighting system further comprising a spreading optical element arranged in front of the plurality of light emitting elements to shape the light emitted from the lighting elements, and a controller for varying a light emission angle range of light emitted from the spreading optical element by controlling each of the plurality of controllable light emitting elements. This allows the light emitted from the spreading optical element to be varied without varying any physical parts of the lighting system, because the controller now controls each of the light emitting elements, by e.g. dimming one or more of the light emitting elements or by switching one or more of the light emitting elements off. | 5 |
TECHNICAL FIELD
[0001] This disclosure relates to the field of footwear, more particularly, relates to a footwear accessory apparatus.
BACKGROUND
[0002] Nowadays, shoe laces are usually used to fasten the shoe by tying a bow. However, the inconvenience of lacing and unlacing the bowie forces the user to worn out their shoes quickly. For example, when putting on the shoes, a user may force her feet into the shoes without unlacing the bowtie. On the other hand, the user may remove one shoe by stepping one foot on the shoe to push it down while lifting up the other foot inside the shoe. Such putting on and off manners may cause the inner walls of the shoe expand and stretch. At the same time, the heel part may be damaged. As a result, the lifetime of the shoe is shortened. Moreover, the shoes may quickly get dirty.
[0003] Currently, one alternative for the shoe lace available in the market is Xpand. The Xpand product relates to expandable lace that allows the user to slip on and slip off their shoes without using a bowtie. Though the Xpand product eliminates the bow tie, it does not solve the problem of the damaging and stretching of the shoe.
SUMMARY
[0004] In order to solve the above problems in the prior art, the present applicant provides a footwear accessory apparatus that facilitate the taking on and off of the shoe for the user. To put on the shoe, the user only needs to snap the footwear accessory apparatus. It is easy and convenient. To remove the shoe, with a simple kick on the button using the heel of another foot, the snap detaches. When the snap is detached, the user can slip out her foot without any difficulty. As such, the problem of stretching and expanding of the shoe caused by removing the shoe forcibly is solved. Also, likely to dirty the shoe when removing it.
[0005] Another benefit of the invention is that the user does not need to bend down to take off the shoe. Consumers such as athletes and elders with arthritis or back problems will benefit from that.
[0006] Yet another advantage of the invention lie in that since the lifetime of the shoe is saved, there are less amount of shoes end up in a land filling. Thus, on a global scale, the invention is beneficial towards the environment.
[0007] In one embodiment, a footwear accessory apparatus may include a main portion, and an arm portion. The main portion may include a control device. The arm portion may include a pivoting end coupled with the main portion and a free end detachably coupled to the main portion. The control device may be used to detach the free end of the arm portion from the main portion.
[0008] In another embodiment, a footwear may include a front portion, a bottom portion, a first side, a second side, and a footwear accessory apparatus. The main proportion may be coupled with the first side, and the arm portion may be coupled with the second side. The footwear accessory apparatus may include a main portion and an arm portion. The main portion may include a control device. The arm portion may include a pivoting end coupled with the main portion and a free end detachably coupled to the main portion. The control device may be used to detach the free end of the arm portion from the main portion.
[0009] In yet another embodiment, a footwear may include a front portion, a bottom portion, a first side, and a second side. The first side may include a main portion. The main portion may include a control device. The second side may include an arm portion. The arm portion may include a pivoting end coupled with the main portion and a free end detachably coupled to the main portion. The control device may be used to detach the free end of the arm portion from the main portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention will be further explained with reference to the accompanying drawings and the following description. Wherein:
[0011] FIG. 1A is a perspective view of the footwear accessory apparatus in accordance with one embodiment of the present invention where the arm portion is detached from the main portion.
[0012] FIG. 1B is a perspective view of the footwear accessory apparatus in accordance with one embodiment of the present invention Where the arm portion is snapped on the main portion.
[0013] FIG. 1C is a perspective view of the footwear accessory apparatus in accordance with another embodiment of the present invention where the arm portion is detached from the main portion.
[0014] FIG. 1D is a perspective view of the footwear accessory apparatus in accordance with another embodiment of the present invention here the arm portion is detached from the main portion.
[0015] FIG. 1E is a perspective view of the footwear accessory apparatus in accordance with yet another embodiment of the present invention.
[0016] FIG. 1F is a perspective view of the footwear accessory apparatus in accordance with still another embodiment of the present invention.
[0017] FIG. 1G is a side view of the footwear accessory apparatus in accordance with still another embodiment of the present invention.
[0018] FIG. 2 is an explosive view of the footwear accessory apparatus in accordance with one embodiment of the present invention.
[0019] FIG. 3A is a perspective view of a footwear incorporated with the footwear accessory apparatus in accordance with one embodiment of the present invention.
[0020] FIG. 3B is a partial view of a footwear incorporated with the foots Tear accessory apparatus in accordance with one embodiment of the present invention.
[0021] FIG. 4A is a perspective view of a lace holder.
[0022] FIG. 4B is a perspective view of a lace holder, illustrating that the lace is held in place by the lace holder.
[0023] FIG. 5A is a perspective of a footwear in accordance with another embodiment of the present invention, where the arm portion is snapped on the main portion.
[0024] FIG. 5B is a perspective of a footwear in accordance with another embodiment of the present invention, where the arm portion is detached from the main portion.
[0025] FIG. 6A is a perspective view illustrating that the user has put on the footwear.
[0026] FIG. 6B is a perspective view illustrating that the user is kicking on the button on the footwear accessory apparatus.
[0027] FIG. 5C is a perspective view illustrating that the arm portion is unlocked from the main portion of the footwear accessory apparatus.
DETAILED DESCRIPTION
[0028] FIG. 1A is a perspective view of the footwear accessory apparatus in accordance with one embodiment of the present invention when the arm portion is detached from the main portion. FIG. 1B is a perspective view of the footwear accessory apparatus in accordance with one embodiment of the present invention when the arm portion is snapped on the main portion.
[0029] As shown in FIGS. 1A and 1B footwear accessory apparatus 10 in accordance with one embodiment of the present invention may include main portion 102 and arm portion 104 . main portion 102 may include button 106 and a series of holes 108 that allow lace to pass through. arm portion 104 may include a series of holes 110 that allow the lace to pass through, pivoting end 112 , and free end 114 . arm portion 104 is coupled with main portion 102 at pivoting end 112 . arm portion 104 can move pivotally with respect to pivoting end 112 . As shown in FIG. 1A , free end 114 of arm portion 104 may snap on main portion 102 . As shown in FIG. 1B , free end 114 of arm portion 104 may detach main portion 102 . button 16 can detach free end 114 of arm portion 104 from main portion 12 .
[0030] FIG. 1C is a perspective view of the footwear accessory apparatus in accordance with another embodiment of the present invention where the arm portion is detached from the main portion. FIG. 1D is a perspective view of the footwear accessory apparatus in accordance with one embodiment of the present invention where the arm portion is detached from the main portion.
[0031] As shown in FIGS. 1C and 1D , the structure of the footwear accessory apparatus in this embodiment is similar to that of the embodiment shown in FIGS. 1A and 1B , except that main portion 102 and arm portion 104 may be without holes.
[0032] FIG. 1E is a perspective view of the footwear accessory apparatus in accordance with yet another embodiment of the present.
[0033] As shown in FIG. 1E , one of the holes 108 on the main portion 1024 may be used to lock the lace in place. Hole 108 has L-shaped groove 118 . When the user inserts the lace into hole 108 and pulls it down, the lace may be locked inside L-shaped groove 118 due to friction.
[0034] In some embodiments, more than one holes are provided on the main portion 102 to lock the lace in place.
[0035] In some embodiments, more than one holes are provided on the arm portion 104 to lock the lace in place.
[0036] FIG. 1F is a perspective view of the footwear accessory apparatus in accordance with still another embodiment of the present invention. FIG. 1G is a side view of the footwear accessory apparatus in accordance with still another embodiment of the present invention.
[0037] As shown in FIGS. 1F and 1G , the main portion 102 may include a series of notches 120 on its side, and the arm portion 104 may include a series of notches 122 of its side.
[0038] FIG. 2 is an explosive view of the footwear accessory apparatus in accordance with one embodiment of the present invention.
[0039] As shown in FIG. 2 , footwear accessory apparatus 20 in accordance with one embodiment of present invention may include main portion 202 , an arm portion 204 , button 206 , an elastic assembly 208 , back portion 210 , and hinge 212 , button 206 may include locking portion 214 which can lock arm portion 204 in place when arm portion 204 snaps on main portion 202 .
[0040] In some embodiments, pivoting end 112 of arm portion 104 may be coupled with main portion 102 by a living hinge.
[0041] In some embodiments, the button may be a pivoting point, or alternatively, a living hinge.
[0042] In some embodiments, arm portion 204 can snap on main portion 202 with use of magnets (not shown).
[0043] In some embodiments, arm portion 204 may be released by pressing button, or alternatively, by misting button 206 . In some embodiments, instead of button, it could be slider. In Some embodiments, button 206 can be remotely controlled. In some embodiments, button 206 is round, alternatively, any other shapes, such as rectangular, square, triangular, and etc.
[0044] FIG. 3A is a perspective view of a footwear incorporated with the footwear accessory apparatus in accordance with one embodiment of the present invention. FIG. 3B is a partial view of a footwear incorporated with the footwear accessory apparatus in accordance with one embodiment of the present invention.
[0045] As shown in FIG. 3A , footwear 30 may include front portion 302 , bottom portion 304 , first side 308 , and second side (not shown). A series of holes 314 may extend along first side 308 . Another series of holes (not shown) may extend along second side (not shown). When attaching footwear accessory apparatus 10 to footwear 30 , one end of lace 318 passes through holes 314 on first side 308 and holes 108 on main portion 102 . other end of lace 318 passes through holes (not shown) second side (not shown) and holes 110 of arm portion 104 . As shown in FIG. 3B , excess part of lace 318 can be hold by lace holder 320 . footwear accessory apparatus 10 can be secured on footwear 30 by fastening lace 318 .
[0046] In some embodiments, holes 108 on main portion 102 may be in different shapes, such as round, rectangular, square, triangular, and etc. In some embodiments, holes 110 on arm portion 104 may be in different shapes, such as round, rectangular, square, triangular, and etc.
[0047] In some embodiments, footwear accessory apparatus 10 may be used in athletic shoes, business shoes, dance shoes, or any other types of footwear.
[0048] FIG. 4A is a perspective view of a lace holder. FIG. 4B is a perspective view of a lace holder, illustrating that the lace is held in place by the lace holder.
[0049] As shown in FIG. 4A , lace holder 320 may include three holes 402 , 404 , and 406 . As shown in FIG. 4B , lace 318 may pass through one hole 402 and then another hole 404 , such that lace 318 may be held in place.
[0050] In some embodiments, lace holder 320 may be of different shapes, such as rectangular, square, triangular, round, oval, any combination thereof, or any other shapes.
[0051] FIG. 5A is a perspective of a footwear in accordance with another embodiment of the present invention, where the arm portion is snapped on the main portion. FIG. 5B is a perspective of a footwear in accordance with another embodiment of the present invention, where the arm portion is detached from the main portion.
[0052] As shown in FIG. 5A , footwear 50 according to another embodiment of present invention may include front portion 502 , bottom portion (not shown), first side 506 , and second side 508 . first side 506 may have main portion 510 . second side 508 may have arm portion 512 . main portion 510 may include button 514 . arm portion 512 may include pivoting end 514 and free end 516 . As shown in FIG. 5A , free end 516 may snap on main portion 510 . As shown in FIG. 5B , button 514 can detach free end 516 of arm portion 512 from main portion 510 .
[0053] FIG. 6A is a perspective view illustrating that the user has put on the footwear. FIG. 6B is a perspective view illustrating that the user is kicking on the button on the footwear accessory apparatus. FIG. 6C is a perspective view illustrating that the arm portion is unlocked from the main portion of the footwear accessory apparatus.
[0054] As shown in FIG. 6A , after putting on footwear 60 incorporated with footwear accessory apparatus 10 , the user can snap arum portion 104 on main portion 102 . As shown in FIG. 6B , when removing footwear 60 , the user can slightly kick button 106 on footwear accessory apparatus 10 using bottom portion 304 of other footwear. As shown in FIG. 6C , after kicking button 106 , arm portion 104 is released from main portion 102 of footwear accessory apparatus. Then, the user can take off footwear 60 with ease. As such, putting on and taking off footwear can be easy, fast, and clean.
[0055] In some embodiments, the footwear accessory apparatus can store electronic data.
[0056] In some embodiments, the footwear accessory apparatus may be made of plastic, fabric, metal, any combination thereof or any other materials.
[0057] Advantages of the footwear accessory apparatus lie in different aspects. For example, the bow tie is not necessary. To put on the shoe, the user only needs to snap the footwear accessory apparatus. It is easy and convenient. To remove the shoe, with a simple click on the button, the snap detaches. When the snap is detached, the shoe is in a state as if completely unlaced, and that is the reason why it requires no force for the user to remove her foot out of the shoe. As such, the problem of stretching and expanding of the shoe caused by removing the shoe forcibly is solved. Further, it is less likely to dirty the shoe when removing it.
[0058] Another benefit of the invention is that the user does not need to bend down to take off the shoe. Consumers such as athletes and elders with arthritis or back problems will benefit from that.
[0059] Another advantage of the invention lie in that since the lifetime of the shoe is saved, there are less amount of shoes end up in a land filling. Thus, on a global scale, the invention is beneficial towards the environment.
[0060] Having thus described the disclosure of the present application in detail and by reference to implementations thereof, it will be apparent that modifications and variations are possible without departing from the scope of the disclosure defined in the appended claims. | The present application relates to a footwear accessory apparatus including a main portion, and an arm portion. The main portion includes a control device. The arm portion includes a pivoting end coupled with the main portion and a free end detachably coupled to the main portion. The control device is used to detach the free end of the arm portion from the main port on. | 0 |
CLAIM OF PRIORITY
[0001] The present patent application claims priority from U.S. Provisional Application No. 61/254,380, filed Oct. 23, 2009 and U.S. Provisional Application No. 61/258,262, filed Nov. 5, 2009, both of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a solar water heater with a drainback unit to drain fluid from solar heat collectors connected to the solar water heater.
BACKGROUND OF THE INVENTION
[0003] A conventional solar water heater includes one or more solar collectors for heating a working fluid, a storage tank for storing heated water, and a heat exchanger for transferring the heat in the working fluid to the water in the storage tank. Particularly, the conventional solar water heater has a solar heat exchanger circuit comprising the solar collectors, a solar hot fluid conduit, a solar heat exchanger coil in the heat exchanger, a solar cold fluid conduit, and a solar pump for circulating the working fluid through cold fluid line, through the solar collectors, through the hot fluid conduit, and through the solar heat exchanger coil when heat is being captured by the solar collectors. In addition, the conventional solar water heater has a storage tank heat exchanger circuit comprising the storage tank, cold water siphon conduit, a storage tank heat exchanger coil in the heat exchanger, a hot water return conduit, and a hot water pump for circulating water in the storage tank through the storage tank heat exchanger coil.
[0004] During operation of such a conventional solar water heater, circumstances arise when the working fluid in the solar collectors should be drained from the solar collectors. In order to extend the life of the solar collectors, the working fluid is typically drained from the solar collectors any time that the solar pump is shut down, and the working fluid is not circulating through the solar collectors. The solar pump is shutdown when the requirement for heat for heating the water in the storage tank has ended or when heat is not available from the solar collectors because of the absence of sunlight. By draining the solar collectors, the solar collectors are protected from freezing and corrosion and the working fluid is protected from degradation.
[0005] Draining the working fluid from the solar collectors requires a drainback unit that is part of the solar heat exchanger circuit and that includes a drainback reservoir for storing the working fluid and the necessary plumbing to allow the working fluid to drain from the solar collectors into the drainback reservoir. Conventionally, the heat exchanger is located within the drainback reservoir. When the conventional solar water heater frequently cycles between a heating operation with the solar pump running and a drain back operation with the solar pump shut off, the working fluid in the drainback reservoir typically remains at high temperature, and heat from the working fluid in the drainback reservoir is transferred to the heat exchanger located within the drainback reservoir. When the cycle time between the heating operation with a solar pump running and the drain back operation is long, such as overnight, the working fluid in the drainback reservoir cools, and the working fluid in the heat exchanger and the water in the heat exchanger both become cool. On restart, when heat is again available from the solar collectors, the solar collectors must heat all of the working fluid in the solar heat exchange circuit including all of the drainback working fluid before heat can be transferred by the heat exchanger to the water circulating in the heat exchanger. Consequently, such a conventional drainback unit experiences a substantial startup delay for the delivery of heat to the water in the water storage tank.
[0006] In order for the working fluid to drain into the drainback reservoir, air must displace the working fluid in the solar collectors as the working fluid is drained. Under certain operating conditions, an airlock may develop in the plumbing between the solar collectors and the drainback reservoir thereby preventing the working fluid in the solar collectors from draining into the drainback reservoir. Under such circumstances, the trapped working fluid may freeze in the solar collectors thereby damaging the solar collectors, the trapped working fluid may corrode the solar collectors, or the heat transfer characteristics of the trapped working fluid may, when subjected to extreme cold, degrade.
SUMMARY OF THE INVENTION
[0007] The drainback unit of the present invention addresses both the problem of startup delay described above and the problem of an airlock inhibiting the drain back of working fluid into the drainback reservoir once the solar pump has stopped circulating the working fluid in the solar collectors of the solar heat exchanger circuit.
[0008] In order in order to assure that the working fluid in the solar collectors is consistently drained from the solar collectors, the drainback unit of the present invention has an anti-airlock conduit connecting air in the top of the drainback reservoir to the solar hot fluid conduit to allow the air in the drainback reservoir to bubble through the solar hot fluid conduit to the solar collectors while the working fluid drains by the force of gravity through the solar cold fluid conduit and through the solar pump into the bottom of the drainback reservoir.
[0009] In order to speed the delivery of heat to the water in the storage tank up on restart of the solar pump, the heat exchanger of the drainback unit in accordance with the present invention is located outside of the drainback reservoir. Moreover, the drainback reservoir outlet conduit and the drainback reservoir inlet conduit are connected to the drainback reservoir near the bottom of the drainback reservoir and in close proximity to each other. Consequently, upon restart, the solar collectors need only heat the working fluid in the solar collectors, the solar hot fluid conduit, the solar cold fluid conduit a small layer of working fluid near the bottom of the drainback reservoir and before the heat exchanger can begin delivering heat to the water in the storage tank.
[0010] Further objects, features and advantages will become apparent upon consideration of the following detailed description of the invention when taken in conjunction with the drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic drawing of a solar water heater with a drainback unit in accordance with the present invention.
[0012] FIG. 2 is a perspective view of the drainback unit for the solar water heater in accordance with the present invention.
[0013] FIG. 3 is a perspective elevation view of the drainback unit (cover removed) for the solar water heater in accordance with the present invention.
[0014] FIG. 4 is a detailed section view of the anti-airlock conduit connecting the solar hot fluid conduit to the drainback reservoir of the drainback unit in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] Turning to FIG. 1 , a solar water heater 10 in accordance with the present invention comprises a storage tank 16 for holding heated water, one or more solar collectors 12 charged with a working fluid, a heat exchanger 14 for transferring heat, during a heating operation, from the working fluid to the water in the storage tank, and a drainback unit 40 ( FIGS. 2 and 3 ) for collecting the working fluid when the heating operation has terminated. The storage tank 16 forms part of a storage tank heat exchanger circuit 22 , which comprises the storage tank 16 , a cold water siphon conduit 32 , a heat exchanger cold water inlet 28 , a storage tank heat exchanger coil 24 inside the heat exchanger 14 , a heat exchanger hot water outlet 30 , a storage tank water pump 26 , a hot water return conduit 34 , and an air vent 27 , all connected in series as shown in FIG. 1 .
[0016] The solar collectors 12 form part of a solar heat exchange circuit 46 , which comprises the solar collectors 12 , a solar hot fluid conduit 54 , a solar heat exchanger coil 48 inside the heat exchanger 14 , a drainback reservoir inlet conduit 62 , a drainback reservoir 44 , a drainback reservoir outlet conduit 60 , a solar fluid pump 50 , and a solar cold fluid conduit 52 , all connected in series as shown in FIG. 1 . The drainback reservoir 44 and an anti-airlock conduit 56 connected between the solar hot fluid conduit 54 and the top of the drainback reservoir 44 comprise the drainback unit 40 . The anti-airlock conduit 56 of the drainback unit 40 is illustrated in greater detail in FIG. 4 . As shown in FIG. 3 , the heat exchanger 44 is physically located outside of the drainback reservoir 44 . Further, the drainback reservoir outlet conduit 60 and the drainback reservoir inlet conduit 62 are located adjacent to each other and near the bottom of the drainback reservoir 44 .
[0017] With continued reference FIG. 1 , the storage tank 16 receives cold water from a pressurized source of cold water (not shown) via cold water supply line 21 and storage tank inlet conduit 18 . Hot water in the storage tank 16 is delivered from the storage tank 16 to a water system (not shown) via a storage tank outlet conduit 20 , a mixing valve 19 , and a hot water output line 23 . In order to store the most amount of heat in the storage tank 16 , the water in the storage tank 16 is maintained at a temperature well above the temperature of the water required by the water system. The mixing valve 19 serves to reduce the temperature of the water flowing in the storage tank outlet conduit 20 by injecting cold water from the cold water supply line 21 to produce water in the hot water output line 23 that is of the appropriate temperature for use by the water system. The storage tank 16 is further equipped with a conventional temperature/pressure relief valve 25 to prevent over temperature or over pressure build up in the storage tank 16 .
[0018] In order to heat the water in the storage tank 16 , solar energy is collected by the solar collectors 12 which in turn heat the working fluid in the solar heat exchanger circuit 46 . The working fluid may include among other fluids, water, glycol, glycol/water mixtures, alcohols, alcohol/water mixtures, and other heat transfer fluids known to those persons of ordinary skill in the art. During a water heating operation, the working fluid in solar heat exchanger circuit 46 is circulated by means of solar fluid pump 54 in the direction shown by the arrows in FIG. 1 . Cool working fluid is drawn from the drainback reservoir 44 through the drainback reservoir outlet conduit 60 by the solar fluid pump 54 and forced through solar cold fluid conduit 52 into the solar collectors 12 . As the working fluid passes through the solar collectors 12 , the working fluid is heated and exits through solar hot fluid conduit 54 . A hot fluid temperature sensor 72 is connected to the solar hot fluid conduit 54 adjacent the solar collectors 12 to determine the temperature of the working fluid as it exits the solar collectors 12 . The working fluid then passes from the solar hot fluid conduit 54 into the solar heat exchanger coil 48 of the heat exchanger 14 . In the heat exchanger 14 , the working fluid gives up its heat to the storage tank heat exchanger coil 24 , and the working fluid, in a cooler state, exits the solar heat exchanger coil 48 and into the drainback reservoir 44 through drainback reservoir inlet conduit 62 . The working fluid in the drainback reservoir 44 is withdrawn through drainback reservoir outlet conduit 60 by the solar fluid pump 50 and the heating operation cycle continues. The drainback reservoir 44 is equipped with a pressure relief valve 45 to accommodate any overpressure condition that might exist inside the drainback reservoir 44 .
[0019] The water in the storage tank heat exchanger circuit 22 as previously stated is heated in the heat exchanger 14 when the working fluid in the solar heat exchanger coil 48 gives up its heat to the storage tank heat exchanger coil 24 . The water in the storage tank heat exchanger circuit 22 is circulated by means of the storage tank water pump 26 . The storage tank water pump 26 circulates the water in the storage tank heat exchanger circuit 22 by drawing the water in the storage tank 16 through the cold water siphon conduit 32 , the heat exchanger cold inlet 28 , the storage tank heat exchanger coil 24 of the heat exchanger 14 , and the heat exchanger hot outlet 30 . The storage tank water pump 26 then forces the heated water through the hot water return conduit 24 and back into the storage tank 16 . An air vent valve 27 is provided on the hot water return conduit 24 adjacent the storage tank 16 to allow for the exhaustion and intake of air to and from the storage tank 16 as the water level in the storage tank 16 rises and falls. A storage tank temperature sensor 70 is connected to the storage tank 16 to sense the temperature of the water in the storage tank 16 .
[0020] The operations of the storage tank water pump 26 and the solar fluid pump 50 are controlled by the control module 74 . The control module 74 monitors the temperature of the working fluid in the solar hot fluid conduit 54 as sensed by the hot fluid temperature sensor 72 and the temperature of the water in the storage tank 16 as sensed by the storage tank temperature sensor 70 . When the temperature of the working fluid exceeds the temperature of the water in the storage tank, typically by a differential of 16° F., the control module 74 recognizes that the solar collectors 12 are producing sufficient heat to begin heating the water in the storage tank 16 . At that point, both the storage tank water pump 26 and the solar fluid pump 50 are turned on, and a heating operation is commenced. Once the differential between the hotter working fluid in the solar collectors 12 and the water in the storage tank 16 drops to a predetermined differential value, typically 6° F., the control module 74 recognizes that the water temperature is sufficiently high, the storage tank water pump 26 and the solar fluid pump 50 are shut off, and the heating operation ceases. The control module 74 also monitors both the working fluid temperature and the water temperature, by means of the hot fluid temperature sensor 72 and in the storage tank temperature sensor 70 , for safe maximum temperatures.
[0021] Once a heating operation has ceased, the working fluid should be drained from the solar collectors 12 and stored in the drainback reservoir 44 . As the working fluid drains from the solar collectors 12 through the solar cold fluid conduit 52 and the solar fluid pump 50 and into the drainback reservoir 44 , air must flow into the solar collectors 12 through the solar hot fluid conduit 54 , or the solar collectors 12 become airlocked, and the working fluid will not drain from the solar collectors 12 . In order to supply vacuum relief air to the solar collectors 12 through the solar hot fluid conduit 54 , the present invention includes an anti-airlock conduit 56 connected between the top of the drainback reservoir 44 , where there is a supply of air, and the solar hot fluid conduit 54 as shown in detail in FIG. 4 . The anti-airlock conduit 56 has a cross sectional area that is less than half the size of the cross-sectional area of the solar hot fluid conduit 54 . Through testing, the preferred ratio of the cross-sectional area of the anti-airlock conduit 56 to the cross-sectional area of the solar hot fluid conduit 54 is approximately 1:36, which is the ratio resulting from the use of a ¾ inch solar hot fluid conduit 54 and a ⅛ inch anti-airlock conduit 56 . The proper ratio of the cross-sectional areas ensures that sufficient air can bubble up through the solar hot fluid conduit 54 during a drain back operation to displace the working fluid that drains from the solar collectors 12 through the solar cold fluid conduit 52 . By the same token, the proper ratio of the cross-sectional areas ensures that during a heating operation, significant amounts of working fluid circulating through the solar hot fluid conduit 54 are not diverted into the drainback reservoir 44 instead of into the heat exchanger 14 .
[0022] By locating the heat exchanger 14 outside of the drainback reservoir 44 and by placing the drainback reservoir inlet conduit 62 from the solar heat exchanger coil 48 adjacent the drainback reservoir outlet conduit 60 , the delay in providing heat at the startup of a heating operation after a drain back operation can be minimized. Particularly, where the working fluid has been drained from the solar collector 12 overnight or for an extended period of time, the temperature of the working fluid in the drainback reservoir 44 will be cold. Consequently, the amount of time required for startup depends on how quickly the circulating working fluid can be heated in the solar collectors 12 . The startup time depends on the amount of working fluid that must be heated by the solar collectors 12 . By limiting the amount of working fluid to only the working fluid in the solar collectors 12 , in the solar cold fluid conduit 52 , in the solar hot fluid conduit 54 and in small layer of working fluid in the drainback reservoir 44 adjacent the drainback reservoir outlet conduit 60 and the drainback reservoir inlet conduit 62 , the startup delay can be minimized
[0023] While this invention has been described with reference to preferred embodiments thereof, it is to be understood that variations and modifications can be affected within the spirit and scope of the invention as described herein and as described in the appended claims. | A solar water heater includes a drainback unit with a drainback reservoir and an anti-airlock conduit for assuring that working fluid in the solar collectors is consistently drained from the solar collectors into a drainback reservoir once circulation the working fluid in the solar collectors has stopped. The drainback unit also provides rapid startup by positioning the heat exchanger outside of the drainback reservoir and by positioning the inlet and outlet of drainback reservoir in close proximity to each other. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a long flexible pipe having an impermeable internal metal tube and more particularly to a flexible pipe including an internal corrugated metal tube which is, in particular, gas-impermeable.
The present invention also relates to a flexible pipe for transporting fluids at high pressure such as, for example, that used during operations for extracting crude oil from a subsea deposit. Such a pipe must, in particular, withstand the various forces to which it is subjected such as, for example, the internal and/or external pressures developed in and on the said flexible pipe, and must have a degree of flexibility along its longitudinal axis so that it can bend without risk of rupturing.
Under extreme service conditions such as, for example, in Arctic regions where very difficult climatic conditions prevail or else for transporting liquefied natural gas, it has been proposed to use either rigid steel pipes or flexible pipes which include an internal corrugated metal tube, as described in FR-A-2,458,022.
Other structures are also described in WO 96/17198 or GB-A-1,486,445.
The flexible pipe described in FR-A-2,458,022 comprises, from the inside to the outside:
an internal corrugated metal tube;
a metal casing wound around the internal corrugated tube and consisting of profiled wires, the winding pitch of which is in the opposite direction to the pitch of the corrugations of the said internal corrugated tube, this metal casing providing the bursting strength and called a pressure vault;
two crossed armouring plies which provide the resistance to tensile loads and to the end cap effect due to the internal pressure of the pipe; and
an external sleeve for protection and sealing.
In a variant, it is proposed to use as pressure vault a winding of a round wire which is housed in the troughs of the corrugations of the internal corrugated tube.
However, such a pipe has many drawbacks both with regard to the structure and from the behavior standpoint.
In order to reinforce the internal corrugated tube, it is internally lined with an overlapping flat and welded spiralled metal tape or with a smooth tape, the space between the corrugations of the internal tube and the tape being optionally filled with a filling material. Consequently, this is a substantially more rigid structure which must be wound onto a large-diameter drum and which is fragile during the unwinding and winding operations in manufacture. When the corrugated tube is not reinforced with the aforementioned tape, then any momentary elongation of the pipe, as occurs when it is under tension, may generate a permanent elongation of the internal tube sometimes leading to rupture. Finally, whatever the recommended pressure vault, there is a risk of ovalizing the internal tube.
Whatever the circumstances, the flexible pipe of the prior art is unable to withstand the very high external pressures which develop at great depths, of the order of several thousands of meters, and/or the very high internal pressures developed in the pipe during exploitation operations.
The object of the present invention is to remedy the aforementioned drawbacks and to provide a flexible pipe which not only is capable of withstanding pressures of several hundred bar exerted on the outside and/or on the inside of the pipe, but also of being able to be used at high temperatures and in an acid medium, i.e. capable of high performance in a corrosive medium, and of being suited for what those skilled in the art call "SOUR SERVICE".
The subject of the present invention is a flexible pipe of the type comprising, from the inside to the outside, an internal corrugated metal tube, a pressure vault obtained by winding at least one shaped wire around the said internal tube, a polymeric sleeve around the said pressure vault, at least one armoring ply for resistance to tensile loads and an impermeable external sleeve, the pressure vault having a helical corrugated inner surface comprising at least concave and rounded parts and convex rounded parts, the outer surface of the internal metal tube bearing in its concave rounded part on a convex part of the inner surface of the pressure vault and in its convex rounded part on a concave part of the inner surface of the pressure vault, the said inner surface of the vault and the said outer surface of the internal tube being in shape correspondence, and it is characterized in that the ratio of the height (h) of a corrugation (8) to the pitch (T) of the said corrugation is less than 1 and greater than 0.035, the gap (i) between two consecutive turns being small but not zero.
According to another characteristic, the flexible pipe is characterized in that the pressure vault is made from a wire wound around the said internal tube, each turn having a width approximately equal to the period of the corrugation of the internal tube.
According to another characteristic, the flexible pipe is characterized in that the gap between two consecutive turns lies more or less vertically in line with a crest of the corrugation of the internal tube.
According to another characteristic, the flexible pipe is characterized in that the gap between two consecutive turns lies more or less vertically in line with a trough of the corrugation of the internal tube.
According to another characteristic, the flexible pipe is characterized in that the pressure vault is made from several wires wound around the internal tube.
According to another characteristic, the flexible pipe is characterized in that the internal corrugated tube has corrugations, the radius of curvature (R) of a crest of which is greater than or equal to the radius of curvature (r) of a trough.
According to another characteristic, the flexible pipe is characterized in that the internal corrugated tube is made of a metallic material having a low modulus of elasticity and being resistant to a corrosive medium.
Other advantages and characteristics will become more apparent on reading the description of several embodiments according to the invention, as well as on examining the appended drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial view in perspective of a flexible pipe according to the invention, certain parts of which are not complete;
FIG. 2 is a partial diagrammatic representation of a longitudinal section of the flexible pipe of FIG. 1;
FIG. 3 is a partial enlarged view of part of FIG. 2, the pipe being in flexure;
FIG. 4 is a partial view in cross-section of the internal corrugated tube illustrated in FIGS. 1 to 3;
FIG. 5 is a partial diagrammatic cross-sectional view of a vault/internal corrugated tube assembly according to a first embodiment of the invention;
FIG. 6 is a partial diagrammatic cross-sectional view of a vault/internal corrugated tube assembly according to another embodiment of the invention;
FIG. 7 is a partial diagrammatic cross-sectional view of a vault/internal corrugated tube assembly according to another embodiment of the invention;
FIGS. 8 and 9 are, respectively, partial diagrammatic cross-sectional views of the vault/internal corrugated tube assemblies according to other embodiments of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
The flexible pipe according to the invention, as illustrated in FIG. 1, comprises, from the inside to the outside, an internal corrugated metal tube 1, a pressure vault 2, a sleeve 3, generally made of a thermoplastic having a high melting point, intended to prevent flattening under the high external pressures exerted on the said pipe and called by those skilled in the art an anticollapse sleeve, two crossed armouring plies 4 and 5, the armoring wires of one ply making an angle of less than 55° with respect to the longitudinal axis A of the pipe, an intermediate tape 6 and finally an external sealing sleeve 7. Apart from the internal tube 1 and the pressure vault 2, which form the subject of the present invention, all the other constituent components of the pipe are well known to those skilled in the art and will therefore not be described in detail, even if some of them, such as the tape 6, have formed the subject of recent improvements, in particular by the Applicant.
The internal corrugated metal tube 1, called hereafter a liner and illustrated in FIGS. 1 to 7, is a metal tube having corrugations 8 uniformly spaced over the entire length, the periodicity of the crests of the corrugations or of the troughs being defined, for the sake of convenience, by a period T even though it may also be denoted by the term "pitch" which is used for the windings.
The period T or pitch of the corrugation (FIG. 2) is identified, by convention, by the projection of the corrugation on the longitudinal axis A of the pipe, which is because the angle of the helix formed by the corrugation is close to 90° with respect to the longitudinal axis A of the pipe.
In a preferred embodiment of the invention, the liner 1 consists of an impermeable metal tube having a minimum thickness of 0.15 millimeters and a slight helical corrugation, i. e. one having a relatively small height h. The shape of the corrugation is defined so as to allow elongation under pressure without the risk of rupture, to allow winding for a defined diameter and to increase the flexibility. Tests carried out have shown that the radius of curvature R of a crest must be at least equal to the radius of curvature r of a trough (FIG. 4). Preferably, the radius R must be between 1.5 and 10 times the radius r and better still between 3 and 5 times the radius of curvature r.
The pressure vault 2 consists, in a first embodiment illustrated in FIGS. 2 and 3, of a helical winding of a shaped wire 9 around the liner 1.
The corrugation 8 of the liner 1, seen from the outside, comprises concave parts 10 and convex parts 11, the period T being equal to the distance separating two successive crests 12 or two successive troughs 13 of the said corrugation 8.
The shaped wire 9 forming the pressure vault 2 comprises, on its inner surface 114, convex rounded parts 15 and concave parts 116. The concave parts 10 of the liner 1 bear on the convex parts 15 of the shaped wire and more generally the concave parts of the liner 1 bear on the convex parts of the inner surface of the pressure vault 2, taken in its entirety and, when the flexible pipe is straight, as illustrated in FIG. 2.
The shaped wire 9 is wound helically, forming turns which are spaced apart, it being possible for the clearance 17 between two consecutive turns 18, 19 to be zero when the pipe is put into flexure. In the case of FIG. 3, in which the shaped wire 9 is rounded on the lateral edges 50, the clearance 17 does not correspond to the gap i, whereas in FIGS. 5 to 7 the clearance is equal to the gap i since the lateral edges of the wire are straight and perpendicular to the longitudinal axis A. Gap i could be understood to mean the space separating two consecutive turns which is taken on the inner surface of the pressure vault 2.
The correspondence between the outer surface of the liner 1 with the inner surface of the pressure vault results in bearing parts being defined which have more or less identical geometrical characteristics. Thus, the convex parts 15 of the inner surface of the pressure vault have a radius of curvature which is equal to the radius of curvature r of the concave parts 10 of the outer surface of the liner 1.
In the case of FIGS. 2 and 3, the winding pitch P of the shaped wire 9 is equal to the period T of the corrugation 8 of the liner 1, and the clearance 17 between two consecutive turns 18, 19 lies opposite the crest or top 12 of the corrugation 8.
As may be seen in FIG. 3, the turns 18, 19 are not completely touching on the outer fiber (upper part of the figure), whereas they are touching on the inner fiber (lower part of the figure) because of the fact that the flexible pipe is in flexure.
The shape correspondence between the outer surface of the liner 1 and the inner surface of the pressure vault 2, and because they bear on each other over a large proportion of the surface and because of the small clearance between turns, means that, when the pipe is put into flexure, the neutral fiber, which is normally in coincidence with the longitudinal axis A, can move slightly towards the inner-fiber surface of the liner. Thus, the risk of localized buckling in the concave and/or convex inner-fiber parts of the liner 1 is avoided or greatly reduced. Consequently, the clearance 17 between the consecutive turns which existed in the inner fiber disappears and the said turns are touching whereas, in the outer fiber, the clearance 17 increases and the liner 1 is therefore put into tension, the winding pitch and the period of the corrugation increasing in turn. The convex parts 11 of the liner 1 partially separate from the inner surface of the pressure vault and work in the manner of a membrane when a pressurized fluid flows in the flexible pipe.
In a preferred embodiment of the invention, the ratio of the height h of the corrugation 8 to the thickness e of the liner 1 is between 1 and 30 and preferably between 1.5 and 20 (FIG. 4) . In addition, the ratio h/T is less than 1 and greater than 0.05 and preferably lies between 0.15 and 0.35. The clearance 17 between consecutive turns is small and less than 0.15 1, 1 being the width of a turn.
In order to prevent the liner 1 from deforming due to the effect of the internal pressure of the fluid flowing in the flexible pipe and to ensure contact between the liner 1 and the pressure vault 2 over the entire circumference of the liner 1, it is preferable to use materials having a low modulus of elasticity such as certain steels, titanium, aluminium or aluminium alloys. The choice of material must take account of the resistance to the corrosive medium.
Since the liner 1 is gas-impermeable and resistant to a corrosive medium, it is no longer necessary to take the criterion of resistance to a corrosive medium into account when choosing the material constituting, in particular, the pressure vault 2. For the latter, it is sufficient to choose a material having high mechanical properties and able to be easily formable. Among the possible materials, mention may be made of a steel of the XC 35 type according to the usual standards. This is also true for the tension armouring; consequently, the weight and cost of the flexible pipe may be considerably reduced.
Finally, because the metal liner 1 is gas-impermeable, the anticollapse sleeve 3 may be made of a lower-performance material than that normally used in flexible pipes, the sole criterion to be taken into consideration being the temperature withstand capability.
FIG. 5 illustrates another embodiment in which the liner 1 is identical to that illustrated in FIGS. 2 to 4, but its pressure vault 2 is made with a shaped wire 20, each turn of which has two concave parts 21a and 21b lying on each side of a convex part 22. Consequently, the concave parts 21a and 21b of two consecutive turns match the convex part 11 of the liner 1, the clearance 17 existing between the two consecutive turns being equal to the gap i and lying opposite the crest or top 12 of the convex part 11, this being because the lateral edges 23 of the shaped wire 20 are straight and perpendicular to the longitudinal axis A. In addition, the width l of each turn is approximately equal to the period T of the corrugation.
FIG. 6 illustrates an embodiment which is similar to that in FIG. 5, except that each turn comprises a concave part 24 which matches the shape of the corresponding convex part 11 of the liner 1, the said concave part 24 being surrounded by two convex parts 25a and 25b. In this case, the gap i lies opposite the trough of the corrugation.
In another embodiment illustrated in FIG. 7, the pressure vault 2 consists of two alternate windings of shaped wires 26 and 27 which are in such a way that two consecutive turns 26' and 27' are symmetrical with respect to the junction planes 28 and 28'. The junction plane 28' passes through the bottom of a trough of the corrugation 8 while the junction plane 28 passes through the top of the crest of the said corrugation, the objective being that two consecutive turns 26', 27' of the two alternate windings form something akin to the single turn in the FIGS. 5 or 6.
FIG. 8 illustrates another embodiment in which the liner 1 is identical to the previous embodiments, while the pressure vault 2 consists of a winding of two differently shaped wires. The first shaped wire 29 has a part 30, of concave shape, which matches the convex part of the liner 1 and extends between two consecutive inflection points 31, 32 of a corrugation. The second shaped wire 33 has a part 34, of convex shape, which matches the concave part of the liner 1 and extends between two consecutive inflection points; the combination of the shaped wires 29 and 23 may be likened to a single turn which would have a width equal to the period T of the corrugation, apart from the gaps. In this case, the gaps lie opposite the mid-part 35 of the corrugation, lying between the convex and concave parts of the liner 1.
FIG. 9 illustrates another embodiment in which the pressure vault consists of a winding of two different wires 36, 37.
The shaped wire 36 is a round wire, the radius of which is approximately equal to the radius r:, and is housed in the troughs of the corrugation 8.
The shaped wire 37 is more complex and is adapted, in its central part 38, so as to match the shape of the convex part of the corrugation 8, the junction zone between the two shaped wires 36 and 37 lying more or less vertically in line with the trough of the corrugation. Of course, the lateral parts 39 of the shaped wire 37 must correspond to the round wire 36 in order to achieve a certain uniformity.
In all the embodiments, the consecutive or adjacent turns may have, on their external surfaces, recesses 40 with which connection devices, such as clips 41, engage in order to connect two consecutive or adjacent turns together, thus limiting excessive elongation of the pressure vault (FIG. 5).
In order to make it easier to extrude the anticollapse sleeve 3 onto the pressure vault 2, the latter has a cylindrical outer surface 42 when the pipe is straight, as illustrated in FIG. 2 and other figures.
The cylindrical outer surface 42 forms a good bearing surface for the anticollapse sleeve 3.
Moreover, it should be noted that, according to the invention, each armouring 4, 5 surrounding the anticollapse sleeve 3 consists of the helical winding of at least one ply of wire wound at a setting angle of less than 55°. Preferably, the flexible pipe comprises two plies of wound wires 4, 5 with the same setting angle but in opposite directions, the said plies themselves being surrounded by a sleeve 7 for protection and sealing, with or without a tape 6 being interposed.
The pressure vault 2 may be wound using a pair of identical wires or using two pairs of shaped wires, each of the latter pairs comprising a shaped wire of a given cross-section and another shaped wire of a cross-section which corresponds to the given cross-section.
A preferred process for forming the pressure vault 2/liner 1 assembly consists:
in unreeling, from a feed roll, a long thin tape;
in passing the said tape through forming means in order gradually to give it the shape of a hollow cylinder;
in continuously producing, along a generatrix or in a helix, a weld between the free edges in order to form a cylindrical impermeable hollow tube;
in passing the impermeable hollow tube through corrugating means consisting, for example, of press rollers and, optionally, of a rotating core having a helical corrugated surface; and
in winding one or more shaped wires around the corrugated internal tube.
Such an assembly may be wound with a long length onto a storage reel, awaiting the completion of the flexible pipe.
Of course, other manufacturing processes may be used. Among these, mention may be made of that consisting in butt-joining short lengths of hollow cylinders and then in forming the necessary corrugations on the said hollow tube thus obtained before winding the shaped wire or wires constituting the pressure vault. | The invention concerns a flexible conduit comprising an internal gasproof undulating metal tube (1), the wall of which has helical undulations (8), the external surface of said internal tube having at least concave (10) and convex (11) rounded parts corresponding to the internal and external parts of the undulations respectively, and at least an arch (2) arranged around said internal metal tube and made up of at least a form wire (9) coiled in spires. The invention is characterized in that the arch (2) has an internal surface with helical undulation, comprising at least concave (16) and convex (15) rounded parts and the external surface of the internal metal tube is supported in its concave rounded part (10) by a convex part (15) of the arch (2) internal surface and in its convex rounded part (11) by a concave part (16) of the arch internal surface, said internal arch surface and said internal tube external surface matching in form and the interstices (i) between the adjacent spires are small. The invention is particularly applicable to flexible conduits used in oil mining. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to an image data processing apparatus with an editing function and, in particular, to an apparatus for registering the image data, through a simplified operation, for editing.
An image data processing apparatus has been developed which stores image data input through a communication line, or image data obtained by a scanner for converting the image of a document to an electric signal, and displays it on a display unit, through a readout operation, so that it may be edited.
In this type of image data processing apparatus, the image data required for an editing operation is extracted from the displayed image data and is registered as image data called "parts". In the registration of such "parts" image data, the input image data, as well as a plurality of icons representing the editing function, is displayed on the display unit. Among the display icons, there is an area-designating icon which is directed by a pointing device, such as a mouse, in order to designate required portion of the displayed image data. If, among the displayed icons, the icon for "area cut" is designated, the corresponding image data is subjected to an area cut, and is stored in a memory called "a parts box".
The registered image data is read out as required, and is displayed on the display unit. The displayed image may be inserted into another image, if required.
Even if, in the conventional apparatus, all of the image data is registered as "parts", the area-designation and area cut still have to be performed with the input image displayed on the display unit, thus involving a complex operation.
SUMMARY OF THE INVENTION
It is accordingly the object of this invention to provide a new and improved image data processing apparatus with an editing function, which can register all of the displayed image data, as image data for editing, through a simple operation.
According to the present invention, an image data processing apparatus is provided, comprising:
first memory means, for temporarily storing image data;
means for displaying the image data stored in the first memory means;
indicating means for allowing all of the image data which is displayed on the displaying means, to be indicated as one unit to be registered for editing; and
second memory means, for temporarily storing all of the iamge data, in accordance with an indication made by the indicating means.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention can be understood through the following embodiment, with reference to the accompanying drawings in which:
FIG. 1 is a schematic diagram showing an image data processing apparatus according to an embodiment of the present invention;
FIG. 2 is a flowchart for explaining the operation of the embodiment of FIG. 1;
FIGS. 3A and 3B each are a partial, expanded view generally showing one form of a display screen in the embodiment of the present invention; and
FIG. 4 is a view for explaining the operation of the embodiment of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The image data processing apparatus according to the embodiment of the present invention will now be explained below.
In the image data processing apparatus shown in FIG. 1, CPU 12 is connected, as a control means, to multibus 11, so as to control the apparatus as a whole. CPU 12 is operated by a program which is stored in memory 13. Magnetic disc device 15, CMOS memory 16, calendar section 17, and communication buffer 18 are connected to multibus 11, and the magnetic disc device is connected through interface 14 to multibus 11.
Magnetic disc device 15 stores programs necessary for the operation of CPU 12, as well as data for retrieving the image data and various kinds of data bases.
CMOS memory 16 is backed up by a battery, not shown, and stores the current operation states and so on. In the event of a power supply cutoff, memory 16 can thus maintain the current operation data.
Calendar section 17 stores the date data, and circuit line 20 of a LAN (Local Area Network) is connected via communication interface 19 to communication buffer 18, in which case the communication interface can be connected via circuit line 20 to optical disc device 20a at the central office. Communication buffer 18 is used to temporarily store image data, for example, the image data read out of optical disc device 20a at the central office.
CPU 22 (a control unit), on the other hand, is connected between multibus 11 and local bus 21, to perform the image data processing. CPU 22 is operated by a program which is stored in memory 23 connected to local bus 21.
Keyboard 25 is connected via interface 24 to local bus 21, so as to input various kinds of commands as well as the data for retrieving the image data. Mouse 26 is connected as a pointing device to local bus 21 via interface 24. Tablet 28 is connected via interface 27 to local bus 21.
Between local bus 21, on one hand, and first and second image buses 29 and 30, on the other hand, are connected compression/extension circuit 31, S/P (serial/parallel) converter 32, character signal generator 33, elongation/reduction circuit 34, and bus controller 35.
Compression/extension circuit 31 performs the bandwidth compression and expansion of the image data which are stored, for example, in communication buffer 18.
S/P converter 32 converts the serial image data to parallel image data, and includes scanner (a two-dimensional scanner) 36, adapted to output an electric signal corresponding to the image of an optically scanned document, and printer 37, adapted to print out the image data.
Character signal generator 33 generates a character signal corresponding to a character code, and enlarging/reduction circuit 34 performs the enlarging/reduction of the image data.
Bus controller 35 controls first and second image buses 29 and 30. Bit map memory 38 and page buffer 39 are connected to bus controller 35. The image data is stored in bit map memory 38 and displayed on CRT display (display unit) 40 under the control of CRTC (CRT controller) 41 which is connected to local bus 21.
Page buffer 39 stores, for example, the image data read by scanner 36 as well as the image data (parts) necessary for the editing of the image. The image data which is stored in page buffer 39 is managed by the data stored in a management table contained in memory 23. Page buffer 39 has a memory capacity corresponding to a plurality of pages; for example, four pages (4MB) of an A-4 sized document. Page buffer 39 and bit map memory 38 are controlled by address signals from dual address generator 42 which is connected to local bus 21.
The operation of this image data processing apparatus will be explained below, in connection with the registering of the input image data as the "parts" image data necessary for the editing process. In this case, CPU 22 performs an operation as shown in FIG. 2.
When scanner 36 is operated with the document set thereon, the image data of the document to be read out is input to the apparatus at step ST1 and then supplied via S/P converter 32 and bus controller 35 to page buffer 39 where it is stored. At step ST2, the image data which is stored in page buffer 39 is fed via bus controller 35 to bit map memory 38 and then via CRTC 41 to CRT display 40, where it is displayed.
FIG. 3A shows, for example, one form of display. In FIG. 3A, a plurality of icons 51 are defined at the surrounding sides of the display to set various functions, and image area G 1 and G 2 are displayed in the middle of the screen. A maximum of four pages of image data can be displayed simultaneously. A plurality of icons 52 are defined along the two adjacent sides of image areas G 1 and G 2 , and are necessary for the editing of the image data.
In this state of display, it is judged, at step ST3, whether the "parts" image data covers a complete image or a partial image. If, at this time, the icon representing the "parts" image corresponding to the partial image is designated, as is shown enlarged in FIG. 3B, through the use of, for example, mouse 26, the process for the control operation of CPU 22 through CRTC 41 goes to step ST4. If the required image portion of the document (image area) G 1 is designated at the location of its diagonal points with the use of cursors K after icon 51b for area designation has been designated, then the corresponding image portion is recognized. When icon 51c for area cut is designated subsequently, then the corresponding area cut is recognized at step ST5. An address in page buffer 39 corresponding to the designated image data, as well as an address at which the corresponding data is stored as "parts" image data P 1 , is found at step ST5. At step ST7, the designated image data is transferred to an empty area within page buffer 39, as is shown in FIG. 4, through bus controller 35. At step ST8, the management table in memory 23 is updated and it is comprised of, for example, image data memory addresses and data length stored in page buffer 39 which are produced in accordance with the "parts" image data. Then, at step ST9, the "parts" image data P 1 to be extracted is read out of page buffer 39 and, as is shown in FIG. 3, is displayed on CRT display unit 40, noting that icons 53 necessary for an editing operation are displayed adjacent to the sides of the "parts" image corresponding to the image data.
At step ST3, icon 51d for the "parts" image corresponding to the whole of the displayed image is designated by mouse 26 and the process goes to step ST10. If, in this state, all of the image data as the "parts" image is designated, for example, with the use of mouse 26, this is recognized in the apparatus, and the process goes to step ST6. At step ST6, the address of the image data G 2 stored in page buffer 39 is found, together with the address at which the image data G 2 is stored as "parts" image data P 2 . At step ST7, the image data G 2 is transferred within page buffer 39 and used as the "parts" image data P 2 . The management table of memory 24 is updated at step ST8 and "parts" image data P 2 is displayed, at step ST9, on CRT display 40, as is shown in FIG. 3.
In this way, the "parts" image data is read out for the intended object and utilized for the editing of various images, such as cutting and pasting incorporating, partially erasing, add-on character, etc., for example. The edited image data is then stored in the optical disc, and printed out by printer 37.
Although the aforementioned embodiment has been explained by way of inputting the image data by use of scanner 36, the present invention is not restricted thereto. The same operation can also be performed even if, subsequent to a retrieving operation, the image data is input from an optical disc device over communication line 20 at the central office such as LAN, for example.
Although the optical disc device has been explained as being situated at the central office, not with the image data processing apparatus, it may be located with the image data processing apparatus, in which case, subsequent to a retrieving step, the image data can be input to the present apparatus from the optical disc apparatus. In this case, the optical disc device searches the image data stored in the optical disc, and displays it on the display unit. The optical disc device is also capable of editing the image data designated as the "part" and the image data scanned by the scanner.
Furthermore, scanner 36 may be located at the central office, not with the image data processing apparatus.
According to the present invention, if the input image data as a whole is used for the "parts" image, it is not necessary to subject the image data to an area designation and area cut, as in the conventional apparatus. As a result, an easy-to-operate apparatus can be implemented in comparison with the conventional apparatus, thus reducing the processing time which is required for the "parts" image corresponding to the document image.
Even when, from the optical disc apparatus at the central office, for example, connected over the LAN line, necessary image data is retrieved for processing, the occupancy time of LAN becomes shorter, due to the fast processing of the "parts" image data, thus making possible a very advantageous system operation.
The present invention is not restricted to the aforementioned embodiment and can be modified in a variety of ways.
According to the present invention, if the image data as a whole is designated as one "parts" image by the designating means, then the corresponding image data is stored by the control means in the memory means, without the use of an area designation and area cut operation, whereby the whole image can be used as the "parts" image by way of a simpler operation. | An apparatus is disclosed which processes image data. This apparatus comprises an input section which receives image data to be processed, and a memory section which has at least a first memory and a second memory. An input control unit receives the image data input by the input section, to allow it to be stored in the first memory. A display controller reads out the image data stored in the first memory, to display it on a display unit. A indicating unit allows all of the image data displayed on the display unit to be indicated as one unit to be registered for editing. A registration controller allows all of the image data to be stored, as one unit to be registered for editing, in the second memory, indicated in accordance with an indication made by the indicating unit. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present disclosure claims priority of Korean patent application No. 10-2015-0123829 filed on Sep. 1, 2015, the disclosure of which is incorporated hereby in its entirety by reference.
BACKGROUND OF THE INVENTION
[0002] Embodiments of the present disclosure relate generally to a line structure for a semiconductor device and more particularly to a line structure capable of minimizing the number of signal lines performing the same functionality, and synchronizing the signal lines to have the same signal timing.
[0003] As processing speed of a semiconductor device increases, the importance of synchronizing signals performing the same function to achieve the same signal timing also increases Specifically, for products employing several input/output (I/O) signals, such as high bandwidth memories (HBMs), it may be difficult synchronizing each delay and driver memory cell.
[0004] Typically, for a plurality of signal lines to have the same signal timing, a load matching operation is carried out so that lengths of signal lines performing the same function may be adjusted to become identical.
[0005] FIG. 1 is a conceptual diagram illustrating a conventional load matching method for signal lines.
[0006] In FIG. 1 , a transmission line may include metal lines M 1 , M 2 configured to transmit specific signals (I/O data) performing the same function. The metal lines M 1 , M 2 may be disposed between a source and a target. The transmission line may include first signal lines M 1 extending in a first direction; and second signal lines M 2 extending in a second direction, wherein each second signal line is coupled to a corresponding first signal line through a contact CONT.
[0007] Typically, the lengths of short-loading signal lines are extended on the basis of the longest line among signal lines performing the same function. As shown in FIG. 1 , the extended part is formed in a bent (or curved) shape obtained when the signal lines are bent toward regions of other lines. A connection path for signal transmission between a source (acting as a signal transmitter) and a target (acting as a signal receiver) is formed in a bent or curved shape, so that the connection path can be lengthened.
[0008] However, when the signal lines are bent or curved to extend the connection path as described above, a single signal line may occupy two or more line regions as shown in FIG. 1 . Hence, it may not be possible to form other signal lines on regions occupied by the bent or curved lines.
[0009] Therefore, a conventional method for extending the connection path by bending the signal lines to implement load matching may have a disadvantage in that several regions that could be used for line formation may be unnecessarily used or wasted.
[0010] The above issue becomes more problematic as the number of signal lines requiring load matching increases, especially in products such as high bandwidth memories (HBMs).
BRIEF SUMMARY OF THE INVENTION
[0011] Various embodiments of the present disclosure are directed to providing a line structure for load matching of signal lines performing the same function of a semiconductor device, thereby preventing one or more problems due to limitations and disadvantages of the prior art.
[0012] An embodiment of the present disclosure relates to a technology for minimizing the number of signal lines configured to transmit the same signals by improving a layout structure of the signal lines, and synchronizing the signal lines such that they can have the same signal timing.
[0013] In accordance with an aspect of the present disclosure, a line structure for matching of signal lines of a semiconductor device includes: a first signal line extended in a first direction; a second signal line extended in a second direction, and coupled to the first signal line; and a load-adjusting line spaced apart from the second signal line by a preset distance, and coupled to the first signal line.
[0014] It is to be understood that both the foregoing general description and the following detailed description of embodiments are exemplary and explanatory.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic diagram illustrating a layout structure of metal lines for load matching of signal lines according to the related art.
[0016] FIG. 2 is a schematic diagram illustrating a layout structure of metal lines for load matching of signal lines, according to an embodiment of the present disclosure.
[0017] FIG. 3 is a schematic diagram illustrating a layout structure of metal lines for load matching of signal lines, according to another embodiment of the present disclosure.
[0018] FIG. 4 is a schematic diagram illustrating a layout structure of metal lines for load matching of signal lines, according to yet another embodiment of the present disclosure.
DESCRIPTION OF EMBODIMENTS
[0019] Reference will now be made In detail to various embodiments of the invention in conjunction with the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In the following description, a detailed description of related known configurations or functions incorporated herein may be omitted when it may obscure the subject matter and/or may be repetitious.
[0020] Referring to FIG. 2 a layout structure of metal lines for load matching of signal lines is provided, according to an embodiment of the present disclosure. The signal lines may be performing the same function. Load matching may include adjusting the length of signal lines performing the same function to match the length of a reference signal line. The length of a signal line may be adjusted by connecting one or more load-adjusting lines to the signal line.
[0021] Accordingly, with a line structure according to an embodiment of the present disclosure, a connection path through which a signal is actually transmitted between a source (i.e., a signal transmitter) and a target (i.e., a signal receiver) may not be extended by bending the connection path as shown in FIG. 1 , but by adding redundant lines unused for such signal transmission to the connection path, so that the total length of the corresponding lines may become identical to a length of a reference line.
[0022] For example, load-adjusting lines for matching only loading of the corresponding lines irrespective of signal transmission may be coupled to the connection path (i.e., transmission line) for such signal transmission. A detailed description thereof will now be provided with reference to FIG. 2 .
[0023] For example in the embodiment of FIG. 2 a transmission line comprising metal lines M 1 , M 2 is shown The metal lines M 1 , M 2 , may be configured to transmit specific signals (I/O data) performing the same function. The metal lines M 1 , M 2 may be disposed between a source and a target. The transmission line may include first signal lines 10 extending in a first direction and second signal lines 20 extending in a second direction. Each of the second signal lines 20 may be coupled to a corresponding first signal line 10 through a contact (Cont). In the embodiment shown, for example the first signal lines 10 may be formed of metal lines M 1 , whereas the second signal lines 20 may be formed of metal lines M 2 .
[0024] Load-adjusting lines 32 for load matching transmission line to a reference line may be coupled to the first signal lines 10 of the transmission line, respectively, through a corresponding contact (Cont). For example, the load-adjusting lines 32 may be in the same direction as the second signal lines 20 . The load-adjusting lines 32 may include metal lines formed at the same level (layer) as the second signal lines 20 . For example, the load-adjusting lines 32 may include metal lines M 2 patterned at the same time with the second signal lines 20 .
[0025] Specifically, according to an embodiment of the present disclosure, the load-adjusting lines 32 may be patterned or formed in regions where metal lines M 2 having different functions from the transmission lines ( 10 , 20 ) are not formed. For example, the load-adjusting lines 32 may be formed in the remaining regions outside of the metal line (M 2 ) region, where metal lines ( 42 , 52 ) (e.g. other signal transmission lines, power lines, etc.) needed to operate a semiconductor device may not be formed. Therefore, an embodiment of the disclosure, overcomes the problem that a region in which other lines ( 42 , 52 ) may be formed to implement load matching of the transmission lines 10 , 20 may be unnecessarily wasted or used.
[0026] For example the length of each load-adjusting line 32 may be adjusted according to the length of a reference line. For example, the length of the load-adjusting lines 32 may be determined in a manner that the sum of the lengths of transmission lines and the lengths of corresponding load-adjusting lines 32 may be identical to the length of a reference line.
[0027] FIG. 3 is a schematic diagram illustrating a layout structure of metal lines for load matching, according to another embodiment of the present disclosure.
[0028] In the embodiment of FIG. 2 each load-adjusting line 32 may be formed of a metal line having the same level as the second signal line 20 . For example, FIG. 2 exemplarily shows that each load-adjusting line 32 may be formed of a metal line M 2 corresponding to a higher level than the first signal line 10 .
[0029] In contrast, a load-adjusting line 34 of FIG. 3 is formed of a metal line M 0 corresponding to a lower level than a first signal line 10 .
[0030] For example, if necessary, the load-adjusting lines ( 34 ) may also be replaced with metal lines disposed at upper or lower parts of the first signal line 10 without departing from the scope or spirit of the present disclosure.
[0031] In addition, although FIGS. 2 and 3 exemplarily show that the load-adjusting lines ( 32 34 ) may be formed in the metal line M 2 or the metal line M 0 for convenience of description, the load-adjusting lines ( 32 , 34 ) may also be formed in both of the metal line M 2 and the metal line M 0 as necessary. For example, when we assume that a sufficient-sized space in which all load-adjusting lines can be formed is not available in any one of the metal line M 2 and the metal line M 0 , the load-adjusting lines may also be distributed to two metal lines as necessary.
[0032] FIG. 4 is a schematic diagram illustrating a layout structure for load matching of metal lines, according to yet another embodiment of the present disclosure.
[0033] FIGS. 2 and 3 exemplarily show that one load-adjusting line may be coupled to each transmission line.
[0034] In contrast, the embodiment of FIG. 4 exemplarily chows that several load-adjusting lines ( 36 a, 36 b ) may be coupled to respective transmission lines.
[0035] For example, if it is impossible to form a desired length using a single line, the corresponding load-adjusting line may be divided into a plurality of lines. In this case, the divided load-adjusting lines ( 36 a, 36 b ) may be formed of same-level metal lines (M 2 or M 0 ), or may be formed of different-level metal lines (M 2 and M 0 ).
[0036] As is apparent from the above description, various embodiments of the present disclosure may minimize the number of signal lines configured to transmit the same signals, and/or may synchronize the signal lines so that they can have the same signal timing.
[0037] Those skilled in the art will appreciate that various embodiments of the present disclosure may be carried out in other ways than those set forth herein without departing from the spirit and essential characteristics of these embodiments. The above embodiments are therefore to be construed in all aspects as illustrative and not restrictive.
[0038] Various alternatives and equivalents are possible. The invention is not limited by any particular type of deposition, etching polishing, and/or patterning steps. Nor is the invention limited to any specific type of semiconductor device. For example, the present disclosure may be implemented in a dynamic random access memory (DRAM) device or a nonvolatile memory device. Other additions, subtractions, or modifications will become obvious to those skilled in the art to which the invention pertains in view of the present disclosure without departing from the spirit or scope of the invention as defined by the appended claims. | A line structure for matching of signal lines of a semiconductor device is disclosed. The line structure for matching of signal lines of a semiconductor device includes: a first signal line extended in a first direction; a second signal line extended in a second direction, and coupled to the first signal line; and a load-adjusting line spaced apart from the second signal line by a predetermined distance, and coupled to the first signal line. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
Not applicable.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
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REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISK.
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FIELD OF THE INVENTION
This invention relates to the use of microorganisms for the generation of ethanol from cellulosic waste materials. Novel yeast strains of the genus Kluyveromyces which have the capability to ferment cellulose, or hexose sugars to ethanol are provided. Also provided are methods for converting cellulose, or mixed hydrolysates of hexoses to ethanol by fermentation with Kluyveromyces strains. The invention also provides methods to isolate yeast strains which metabolize cellulose, hexoses, pentoses, or hemicelluloses from waste materials.
BACKGROUND OF THE INVENTION
Ethanol provides a favorable alternative to the use of fossil fuels for energy generation, and increased use of ethanol for fuel could reduce dependence on fossil fuels as well as decrease the accumulation of carbon dioxide in the atmosphere. In the United States, biological production of ethanol, principally by fermentation of grain starches and sugars by yeast, is over four billion liters per year. However, cellulosic biomass potentially provides a far more abundant source of ethanol. Cellulosic biomass represents the greatest carbohydrate resource on earth, and is fixed photosynthetically at a rate of about 10 11 tons per year globally.
Conversion of cellulosic biomass to ethanol requires that the polysaccharides of the biomass first be hydrolyzed to fermentable monosaccharides. Cellulose is a polymer of glucose units, and, while hydrolysis of cellulose is more difficult than hydrolysis of starches, hydrolysis of cellulose yields glucose that is readily fermented by yeasts such as Saccharomyces cerevisiae and Kluyveromyces marxianus . However, cellulosic biomass comprises, in addition to cellulose, more complex and heterogeneous polymers collectively known as hemicellulose. Unlike cellulose, hemicellulose contains saccharides besides glucose—principally the pentose xylose, as well as the pentose arabinose and the hexoses glucose, galactose, and mannose. The pentose content of some cellulosic biomass may reach as high as 35% of the total carbohydrate content (see Rosenberg, Enzyme Microbiol Technol 2:185-193 (1980)). Moreover, in many industrial processes, hemicellulose is hydrolyzed to monosaccharides more efficiently than cellulose. Thus, 35-50% of the fermentable sugars obtained by enzymatic or chemical hydrolysis of cellulosic materials may be derived from hemicellulose, and much of this sugar may be in the form of xylose or arabinose (Harris et al., USDA Forest Products Laboratory General Technical Report FPL-45 (1985)).
Ideally, biological production of ethanol from cellulosic biomass would employ a natural organism capable of efficiently fermenting all five of the most abundant monosaccharides liberated by hydrolysis of cellulose and hemicellulose—glucose, galactose, mannose, xylose, and arabinose—as well as the disaccharide cellobiose produced by enzymatic digestion of cellulose. Even more ideally, such an organism would be able to hydrolyze resilient polymers such as cellulose or hemicellulose without the addition of exogenous enzymes or chemicals.
No such organism is presently known. In particular, while many yeasts will assimilate pentose sugars and hexose sugars, conversion of pentose- and hexose-containing cellulose or hemicellulose to ethanol by yeasts is problematic (see Jeffries & Kurtzman, Enzyme Microb Technol 16:922-932 (1994); Schneider, Crit Rev Biotechnol 9:1-40 (1989)). Fermentation of arabinose to ethanol is almost unknown (see Dien et al., Appl Biochem Biotechnol 57-58:233-42 (1996); McMillan & Boynton, Appl Biochem Biotechnol 45-46:569-84 (1994)). A few yeasts capable of fermenting xylose have been isolated, but their thermotolerance, ability to ferment xylose anaerobically, and their metabolism of hexose sugars are unsatisfactory (see Jeffries & Kurtzman, supra).
Yeasts of the genus Kluyveromyces —particularly thermotolerant strains—have many properties making them well-suited for biological production of ethanol (see Banat et al., World J. Microbiol Biotechnol 14:809-21 (1998); Singh et al., World J. Microbiol Biotechnol 14:823-34 (1998)). Kluyveromyces strains assimilate pentose sugars. However, efficient fermentation of hexoses by Kluyveromyces strains has not been described. A single report of high xylose production by K. marxianus has appeared (Margaritis & Bajpai, Appl Environ Microbiol 44:1039-41 (1982)), but ethanol production was under aerobic conditions and no subsequent report has verified these findings. Other publications report little (Banat et al., supra) or no (Boyle et al., Biotechnol Lett 19:49-51 (1997)) ethanol production from xylose by K. marxianus , even under aerobic conditions.
U.S. Pat. No. 4,472,501 describes a yeast called Kluyveromyces cellobiovorus with the ability to ferment xylose and cellobiose to ethanol, but subsequent analysis of this strain has shown that it does not belong to the genus Kluyveromyces , but rather is an isolate of Candida intermedia (see Molnar et al., Antonie Van Leeuwenhoek 70:67-78 (1996); Ando et al., Biosci Biotechnol Biochem 60:1063-9 (1996); Martini & Martini, Antonie Van Leeuwenhoek 61:57-60 (1992)).
Thus, no Kluyveromyces strain capable of hydrolyzing cellulose has been described. There is a need in the art for thermotolerant organisms capable of both hydrolyzing cellulosic materials, and of efficiently fermenting the hexoses found in hydrolysates to ethanol. The present invention meets these and other needs.
BRIEF SUMMARY OF THE INVENTION
In one aspect, this invention provides biologically pure cultures of yeasts of the genus Kluyveromyces , which grow in media comprising pentose sugars or cellulose as the sole carbon source. In one embodiment of the invention, the biologically pure culture is able to grow in a medium comprising as its sole carbon source a pentose selected from the group consisting of xylose or L-arabinose. In some embodiments, the yeast of the biologically pure culture is of the species Kluyveromyces marxianus . In a further embodiment, the yeast has the identifying characteristics of K. marxianus strain SSSJ-0. In another embodiment of the invention, the biologically pure Kluyveromyces culture is capable of fermenting hexose sugars such as glucose, mannose, galactose, and combinations thereof, to ethanol, under either aerobic or anaerobic conditions. In some embodiments, the culture ferments hextose sugars to ethanol at about 43° C. in a defined medium composed of about 20 g/L of the hexose, about 0.67 g/L yeast nitrogen base, and about 0.25 mM magnesium sulfate in a buffer of about 50 mM citrate, pH about about 4.5, and fermentation proceeds until at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or essentially 100% of the available hexose is converted to ethanol.
The invention also provides novel biologically pure cultures of yeasts of the genus Kluyveromyces , which have the novel property of being capable of growth in media comprising cellulose and cellulose derivatives as the sole carbon source. This cellulose or cellulose derivative may be a variety of soluble or insoluble pure substrates, such as carboxymethylcellulose, AVICEL® (microcrystalline cellulose), or SIGMACELL® (a high purity cellulose powder); alternatively, the cellulose or cellulose derivative may be comprised in a more complex mixture such as the material found in sludges from paper making and recycling, spent grains from brewing operations, sugared lignin hydrolysates, and corn stover hydrolysates. In some embodiments, the yeast of the biologically pure culture is of the species Kluyveromyces marxianus . In a further embodiment, the yeast has the identifying characteristics of K. marxianus strain SSSJ-0. In another embodiment of the invention, the biologically pure Kluyveromyces culture is capable of fermenting cellulose or a cellulose derivative to ethanol without the addition of exogenous cellulases, under either aerobic or anaerobic conditions. In some embodiments, the culture ferments cellulose or a cellulose derivative to ethanol at about 43° C. in a defined medium composed of about 20 g/L dry weight of cellulose or cellulose derivative, about 0.67 g/L yeast nitrogen base, and about 0.25 mM magnesium sulfate in a beffer of about 50 mM citrate, pH about 4.5, and fermentation proceeds until at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or essentially 100% of the available cellulose is converted to ethanol.
In another aspect, the invention provides a method of producing ethanol from an aqueous medium comprising a carbon source selected from the group consisting of cellobiose, glucose, mannose, and galactose. The method comprises the steps of contacting the aqueous medium with a biologically pure culture of yeast capable of proliferation in a medium comprising a hexose as the sole carbon source, and incubating the medium and culture under conditions wherein the carbon source is fermented to ethanol. Such fermentation may be aerobic or anaerobic. In a further embodiment, the ethanol is separated and recovered from the medium following or concurrently with fermentation. In one embodiment, the medium and culture is incubated at a temperature between about 43° C. and about 45° C. In some embodiments of the invention, the biologically pure culture of yeast is of the species Kluyveromyces marxianus , while in a further embodiment, the yeast of the biologically pure culture has the identifying characteristics of strain SSSJ-0. Up to 100% of the available sugars may be converted into ethanol, depending on the time allowed and the conditions of fermentation. In some embodiments, however, conversion of the available sugars to ethanol is less than complete, e.g., at least about 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, or 10% of the available fermentable saccharides are converted to ethanol. In other embodiments, the conversion of sugars to ethanol is expressed as the maximum rate of ethanol production, e.g., about 0.01, 0.05, 0.1, 0.5, or 1 g per hour per liter.
The invention also provides a method producing ethanol from a medium containing cellulose or a cellulose derivative. The method comprises contacting an aqueous medium containing cellulose or a cellulose derivative with a biologically pure culture of a yeast of the genus Kluyveromyces which is capable of growth in a medium containing cellulose as the sole carbon source, and incubating the medium and culture under conditions wherein the cellulose is fermented to ethanol. Fermentation may be aerobic or anaerobic. In a further embodiment, the ethanol is separated and recovered from the medium following or concurrently with fermentation. In one embodiment, the medium and culture is incubated at a temperature between about 43° C. and about 45° C. In some embodiments of the invention, the biologically pure culture of yeast is of the species Kluyveromyces marxianus , while in a further embodiment, the yeast of the biologically pure culture has the identifying characteristics of strain SSSJ-0. Up to 100% of the theoretical yield of ethanol obtainable from the cellulose or cellulose derivative may be obtained, although in some embodiments a lesser percentage of the theoretical yield may be obtained, e.g., at least 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, or 10% of the theoretical yield. In other embodiments, the conversion of cellulose to ethanol is expressed as the maximum rate of ethanol production, e.g., about 0.01, 0.05, 0.1, 0.5, or 1 g per hour per liter.
The invention also provides a method of isolating a biologically pure culture of yeast capable of growth in a medium comprising a pentose such as arabinose or xylose as the sole carbon source. The method comprises the steps of providing a sample of waste material comprising a yeast, culturing a yeast derived from the waste material in a medium comprising a pentose as the sole carbon source, and isolating a biologically pure culture of the yeast, thereby yielding a biologically pure culture of yeast capable of growth in a medium comprising pentose as the sole carbon source. In one embodiment of the isolation procedure, the procedure further comprises the step of culturing the waste material prior to isolation in an enrichment material that supports the growth of yeast in preference to other microorganisms, e.g., contains a high concentration of glucose or is maintained at low pH. In another embodiment of the invention, the enrichment medium comprises a pentose sugar, thereby enriching for organisms able to metabolize pentoses.
The invention also provides a method of isolating a biologically pure culture of yeast capable of growth in a medium comprising cellulose or a cellulose derivative as the sole carbon source. The method comprises the steps of providing a sample of waste material comprising a yeast, culturing a yeast derived from the waste material in a medium comprising cellulose as the sole carbon source, and isolating a biologically pure culture of the yeast, thereby yielding a biologically pure culture of yeast capable of growth in a medium comprising cellulose as the sole carbon source. In one embodiment of the isolation procedure, the procedure further comprises the step of culturing the waste material prior to isolation in an enrichment material that supports the growth of yeast in preference to other microorganisms, e.g., contains a high concentration of glucose or is maintained at low pH. In one embodiment, the enrichment medium comprises 20% glucose and is at pH 4.5.
The invention also provides a method of isolating a biologically pure culture of yeast capable of growth in a medium comprising a hemicellulose or a hemicellulose derivative as the sole carbon source. The method comprises the steps of providing a sample of waste material comprising a yeast, culturing a yeast derived from the waste material in a medium comprising a hemicellulose as the sole carbon source, and isolating a biologically pure culture of the yeast, thereby yielding a biologically pure culture of yeast capable of growth in a medium comprising a hemicellulose as the sole carbon source. The hemicellulose may be chosen from the group of xylans, glucomannans, galactans, glucans, and xyloglucans. In one embodiment of the isolation procedure, the procedure further comprises the step of culturing the waste material prior to isolation in an enrichment material that supports the growth of yeast in preference to other microorganisms, e.g., contains a high concentration of glucose or is maintained at low pH. In another embodiment, the enrichment medium comprises a pentose, to enrich for yeasts which are able to metabolize pentoses liberated by the hydrolysis of hemicellulose.
DEFINITIONS
“Arabinose” refers to the monosaccharide arabino-pentose and its derivatives, occurring primarily as L -arabinofuranose in xylans and xyloglucans.
“Biologically pure culture” refers to a sample of a microorganism that is physically separated from microorganisms of different characteristics. Thus, biologically pure cultures of an organism are substantially free from other organisms naturally found in association with it or naturally occurring in similar source materials. An example of a biologically pure culture is a vessel containing no organisms other than a clonal population of microorganisms derived from a single founder cell. “Biologically pure culture” also refers to a population of organisms derived from a biologically pure culture. Thus, it contemplated that mixed populations of organisms may be generated by secondarily adding other organisms to an existing biologically pure culture. Such a mixed culture comprises a biologically pure culture of the first organism.
“Cellobiose” refers to the disaccharide 4-O-β- D -glucopyranosyl- D -glucose, typically liberated from cellulose by the action of exo-1,4-β-glucanases on cellulose.
“Cellulose” refers to a linear β1-4 glucan with the pyranose units in the − 4 C 1 conformation, in natural form having a molecular mass between about 50 and 400 kDa. Processed forms of cellulose may be characterized by a particular degree of crystallization or polymerization (e.g., AVICEL® or SIGMACELL®)
“Cellulose derivative” refers to cellulose characterized by covalent modification (e.g., carboxymethylcellulose).
“Waste material(s)” or “cellulosic waste material(s)” refers to any substance comprising cellulose, hemicellulose, or cellulose and hemicellulose. Suitable cellulosic waste materials include, but are not limited to, e.g., corn stover, corn fiber, rice fiber, wheat straw, oat hulls, brewers spent grains, pulp and paper mill waste, wood chips, sawdust, forestry waste, agricultural waste, bagasse, and barley straw.
“Fermenting” refers to the biological conversion of a carbon source into ethanol by a microorganism. Fermentation may be aerobic or anaerobic. Anaerobic fermentation takes place in a medium or atmosphere substantially free of molecular oxygen.
“Galactose” refers to the monosaccharide galacto-hexose and its derivatives, occurring primarily as D -galactopyranose in xylans and glucomannans.
“Glucose” refers to the monosaccharide gluco-hexose and its derivatives, occurring primarily as D -glucopyranose in cellulose, glucomannans, and xyloglucans.
“Proliferate” or “proliferation” refers to a sustained period of cell division under a particular culture condition. A microorganism is capable of “proliferation” on culture medium if, being placed in the culture medium and having exhausted the nutritional resources carried over from any previous culture medium, the microorganism continues to divide and incorporate components of the culture medium into living material. When used in the context of growth on a particular carbon source, “proliferation” requires the organism to utilize the carbon source for metabolic energy. Thus, an organism may be capable of assimilating a particular carbon source, and even incorporating it into living material, but not utilizing it for metabolic energy. For example, conventional yeast strains may be able to assimilate pentoses and incorporate them into nucleic acids, but do not utilize them in glycolysis, respiration, or fermentation and therefore cannot grow in media containing pentose as a sole carbon source.
“Hemicellulose derivative” refers to a structural component of plant cell walls other than cellulose and lignin, or a derivative thereof. Hemicelluloses are heterogeneous and vary depending on the origin of the plant material, but the most commonly found components include xylans, glucomannans, galactans, glucans, and xyloglucans. Thus, upon hydrolysis, hemicellulose may yield glucose, galactose, mannose, xylose, or arabinose.
“Isolating” refers to a process by which microorganisms are physically separated from other microorganisms with dissimilar characteristics. Isolation may be carried out, for example, by culture under selective conditions which permit the growth only of a microorganism with unique characteristics, or by inoculating culture medium with microorganisms under conditions in which a physically isolated population of cells is generated from a single founder cell (e.g., limiting dilution or colony growth on solid media).
“ Kluyveromyces marxianus ” refers to a species of yeast which, in its naturally occurring form, typically comprises the sequence shown in SEQ ID NO: 1 in the variable D1/D2 domain of its nuclear large subunit (26S) ribosomal DNA.
“Hexose” refers to C6 sugars and their derivatives, which may occur in pyranose or furanose form. The hexoses most commonly found in plant material are glucose, galactose, and mannose.
“Mannose” refers to manno-hexose and its derivatives, occurring primarily as D -mannopyranose in glucomannans.
“Pentose” refers to C5 sugars and their derivatives, which may occur in pyranose or furanose form. The pentoses most commonly found in plant material are arabinose and xylose.
“Saccharide” refers to monomeric, oligomeric, or polymeric aldose and ketose carbohydrates. Monosaccharides exist preferably as cyclic hemiacetals and hemiketals but may also exist in acyclic forms. Stereoisomers of cyclic monosaccharides can exist in α- or β-forms and in D - or L -forms. Saccharides are also found in modified form, either as natural products or as a result of chemical modification during hydrolysis or industrial processing. Saccharide derivatives include those modified by deoxygenation or addition of moieties such as acetyl, amino, or methyl groups. In oligosaccharides and polysaccharides, saccharide monomers are connected by characteristic linkages, e.g., β1-4, α1-6, α1-2, α1-3, or β1-2. In some polymers, such as cellulose, the linkages are uniform throughout the polymer, while in others, primarily hemicellulosic materials, the linkages may be mixed. Short (typically 1-3 saccharide) branched side chains are also present in polysaccharides, typically from hemicellulose.
“Sole carbon source” refers to an organic molecule, often a carbohydrate, in a culture medium wherein the molecule is the only significant source of metabolic energy available to the microorganism. Thus, the sole carbon source is the only molecule in the medium available to be utilized to ultimately yield ATP by processes such as glycolysis, respiration, and fermentation. Typically, the sole caboun source will account for al least 95%, usually more than 99% by weight of carbohydrate. Typically, culture media comprise other organic molecules besides a “carbon source” (e.g., those found in yeast nitrogen base), but these organic molecules either cannot be metabolized for energy or are present in too low of a concentration to support the continued growth and metabolism of the culture.
“SSSJ-0” refers to a strain of K. marxianus isolated by the methods of the invention and possessing the ability to convert cellulose to ethanol without the addition of exogenous enzymes. The strain was deposited as ATCC No. PTA-3567 on Jul. 26, 2001 in the yeast collection of the American Type Culture Collection (ATCC), 10801 University Blvd., Manassas, Va. 20110.
“Xylose” refers to xylo-pentose and its derivatives, occurring primarily as D -xylopyranose in xylans and xyloglucans.
“Yeast” refers to a unicellular fungus that has a single nucleus and reproduces either asexually by budding and transverse division or sexually through spore formation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B illustrate an alignment comparing the sequence of the D1/D2 variable region of the 26S ribosomal DNA among isolate SSSJ-0, Kluyveromyces marxianus, K. lactis, K wickerhamii , and K. dobzhanskii.
FIG. 2 illustrates growth (i.e., proliferation) of SSSJ-0 on 2% glucose and 2% L-arabinose.
FIG. 3 illustrates growth (i.e., proliferation) of SSSJ-0 on 2% lignin in the presence and absence of yeast nitrogen base (0.67 g/L).
FIG. 4 illustrates growth (i.e., proliferation) of SSSJ-0 on 2% corn stover hydrolysate in the presence and absence of yeast nitrogen base (0.67 g/L).
FIG. 5 illustrates growth (i.e., proliferation) of 2% xylose.
FIG. 6 illustrates growth (i.e., proliferation) of SSSJ-0 on 2% SIGMACELL® and 2% AVICEL®.
DETAILED DESCRIPTION
I. Introduction
The present invention relates to yeasts capable of fermenting cellulose and hexoses to ethanol, methods for isolating such yeasts, and methods for employing such yeasts for generating ethanol from cellulose- or hemicellulose-containing materials such as paper sludges. Yeasts capable of fermenting such carbon sources may be isolated from a variety of cellulose-containing waste materials. Once isolated, the yeasts are typically identified by molecular phylogenetic techniques, as well as by their physiological properties. Pure cultures of these yeasts may then be employed to quantitatively convert cellulose or hydrolyzed hemicellulose into ethanol.
General methods for culturing, manipulating, and analyzing yeast may be found in Guthrie and Fink, Methods in Enzymology v. 194 (Academic Press, NY, 1991) and similar reference works. Methods for manipulating Saccharomyces cerevisiae are generally applicable to the Kluyveromyces strains of the present invention.
II. Isolation of Pentose-Hexose- and Cellulose-metabolizing Yeast Strains from Natural and Industrial Source Materials
A. Source Materials for Isolation
Naturally occurring yeast strains which metabolize pentoses, hexoses, and cellulose may be isolated from a variety of sources. Typically, the source material is an aqueous medium containing cellulose, hemicellulose, or their breakdown products, in which microorganisms with the ability to metabolize pentoses, hexoses, and cellulose may thrive. Industrial waste materials, in which the bioavailability of the cellulose or hemicellulose has been improved by mechanical or chemical processing (e.g., paper pulping), or where cellulose and hemicellulose have been partially or completely hydrolyzed to yield a mixture of hexoses and pentoses, are particularly suitable sources for isolating the yeasts of the invention. Waste materials typically have been exposed to the natural environment (e.g., in a treatment lagoon) which allows colonization of the waste material by the yeasts of the invention. Examples of such materials include bagasse from sugar cane and other crops, rice fibers, oat hulls, corn stover, wheat straw, as well as spent brewer's grains and liquors. A preferred source for isolation of pentose- and cellulose-metabolizing yeast is sludge generated from paper processing, especially recycled paper sludge. Due to the mechanical and chemical disruption of fibers during the pulping process, waste sludge from paper manufacturing is significantly more accessible to hydrolysis as compared to the mostly crystalline form found in native plant material (see Lark et al., Biomass Bioenergy 12:135-43 (1997); Duff et al., Can J Chem Engin 72:1013-1020 (1994)). Accordingly, sludge from papermaking operations is hospitable to colonization by the yeasts of the invention, and cellulose-, hexose-, and pentose-metabolizing yeasts may be reproducibly isolated from such waste materials.
B. Enrichment Procedures
Depending on the environment to which the source material has been exposed, the source material may contain, in addition to the yeasts of the invention, bacteria, protozoans, and other fungi which may metabolize pentoses and cellulosic materials. The presence of these other microorganisms does not interfere with isolation of the yeasts of the present invention; samples of waste material can be cultured directly on standard yeast media or on carbon-source selective media, and the pentose- or cellulose-metabolizing yeasts may be isolated and identified by morphological, physiological, or molecular characteristics. However, to simplify the isolation procedure, or to isolate yeasts present at low concentrations in the source material, the source material may be inoculated into an enrichment medium (typically in liquid form) that favors the growth of the desired yeasts. Enrichment media may select for yeast at the expense of other microorganisms, and/or may comprise a particular saccharide as the sole carbon source to select for yeast able to metabolize the desired saccharide. To select for yeasts, particularly thermotolerant yeasts, enrichment media typically contain a high concentration of glucose, are acidic, and are incubated at high temperatures (about 40° C. to 45° C.). Thus, a typical yeast enrichment medium consists of about 50 mM citrate buffer, pH about 4.5, about 20% glucose, about 2% peptone, and about 1% yeast extract, and enrichment takes place by inoculating the enrichment medium with a waste sample and incubating for about 18 hours at about 45° C. Enrichment media may also contain a particular saccharide derivative in place of glucose (e.g., a hexose, a pentose, cellulose derivative, or hemicellulose derivative) to enrich for yeasts that can utilize the saccharide derivative as a carbon source.
C. Isolation of Biologically Pure Cultures and Phenotypic Selection
A biologically pure culture is typically a population of organisms with identical characteristics, or a clonal population derived from a single founder cell. Thus, to generate a biologically pure culture of yeast from a source material or enrichment culture, one typically performs a culture procedure in which a population of cells is derived from a single founder cell physically separated from other cells. Examples of such procedures include streaking or plating for single colonies on solid substrates, or cloning by limiting dilution in liquid media.
Phenotypic selection occurs by testing a sample of yeast, derived either directly from source material or from an enrichment culture, for the desired physiological property. Typically, the desired physiological property is metabolism or fermentation of a particular carbon source (e.g., cellulose or a pentose). For example, in one embodiment of the invention, yeasts metabolizing cellulose or pentoses are identified by their ability to grow on agar plates or liquid medium containing only cellulose, or only a pentose, as the carbon source. Alternatively, the ability of the yeast to ferment a cellulose may be determined by culturing the yeast in a medium containing the saccharide of interest and monitoring the production of ethanol.
Isolation may be carried out prior to phenotypic selection, concurrently with phenotypic selection, or after phenotypic selection. For example, isolation may be performed prior to phenotypic selection by plating samples of source material or enrichment culture on YPD plates, as in Example 1. Cultures derived from single colonies are then selected for their saccharide growth or fermentation properties, as described in Examples 2 and 3. In an alternative embodiment, concurrent isolation and phenotypic selection may be performed by inoculating a sample of the source material or enrichment culture directly onto a plate containing a particular carbon source. For example, samples of source material or enrichment culture may be spread on plates containing only cellulose or a pentose as a carbon source, and biologically pure cultures isolated from single colonies arising on the selective plate. Finally, isolation of a pure culture may be performed after phenotypic selection. In this embodiment, samples of source material or enrichment culture are grown in medium containing cellulose or a pentose as a carbon source without any attempt to isolate single colonies. Following growth in the selective media, the yeasts are plated on selective or non-selective plates to isolate biologically pure cultures from single colonies.
III. Characterization of Isolated Yeast Strains
Once the desired yeast strain is isolated, its identifying characteristics may be determined by a number of physiological and molecular means. Molecular characterization of isolated strains is performed by analysis of particular nucleic acids, proteins, or other molecules that differentiate one yeast strain from another. Physiological characterization typically identifies the strain by its ability to grow on, assimilate, or ferment various organic substrates.
A. Molecular Characterization
A preferred method to characterize isolated yeasts is to sequence a portion of the nuclear large subunit (26S) ribosomal DNA. Divergence in the variable D1/D2 domain of the large subunit is generally sufficient to resolve individual species of ascomycetous yeasts (Kurtzman & Robnett, Antonie van Leeuwenhoek 73:331-71 (1998)). The D1/D2 sequence may be determined by isolating DNA from a biologically pure yeast sample, amplifying the DNA with primers hybridizing to conserved sequences that flank the D1/D2 region, isolating and sequencing the amplification product, and comparing the sequence of the amplification product to the D1/D2 sequence of known yeasts. Accordingly, in one embodiment, DNA is isolated from an isolated yeast strain and amplified with the primers NL-1 (SEQ ID NO: 2) and NL-4 (SEQ ID NO: 3) of Kurtzman & Robnett. The resulting D1/D2 sequence of isolate SSSJ-0, a cellulose- and pentose-metabolizing strain isolated by the methods disclosed herein and identified as a strain of Kluyveromyces marxianus by its D1/D2 sequence, is shown as SEQ ID NO: 1.
Other methodologies for identifying isolated strains do not require direct sequencing of a characteristic nucleic acid. For example, closely related Kluyveromyces strains may be distinguished by analyzing restriction fragment length polymorphisms (RFLPs) in the non-transcribed spacer 2 region of the ribosomal DNA (Nguyen et al., Can J Microbiol 46:1115-22 (2000)). In addition, randomly amplified polymorphic DNA (RAPD) analysis may be employed to differentiate between many different species of yeast from a variety of genera (Andrighetto et al., Lett Appl Microbiol 30:5-9 (2000); Prillinger et al., Antonie van Leeuwenhoek 75:267-83 (1999)).
B. Physiological Characterization
Yeasts may also be identified characterized by their morphology or physiological characteristics. Physiological characterization typically includes fermentation of sugars, assimilation of various carbon compounds, assimilation of nitrogen compounds, vitamin requirements, temperature tolerance, sensitivity to protein synthesis inhibitors, and splitting of urea (see van der Walt & Yarrow, in The Yeasts—A Taxonomic Study ed. Kreger-van Rij, N. J. W., pp. 45-104, Amsterdam: Elsevier (1984); Barnett et al., Yeasts: Characteristics and Identification 3rd ed., Cambridge: Cambridge University Press (2000)). Differential sensitivity to the toxins produced by a panel of killer yeasts may also be used to identify isolated yeast cultures (Buzzini & Martini, Sys Appl Microbiol 23:450-7 (2000)).
IV. Degradation of Cellulose and Fermentation of Cellulose and Hemicellulose Hydrolysates
Bioconversion of cellulosic material to ethanol by the methods of the present invention usually involves pretreatment, saccharification to fermentable sugars, and fermentation of the sugars to ethanol. Not all steps are essential for every embodiment. For example, paper and hydrolysis waste streams may require little pretreatment before saccharification, while treatments aimed solely at decreasing the insoluble content of waste materials may dispense with fermentation.
A. Starting Materials Comprising Plant Saccharides
Sources of cellulose and hemicellulose suitable for fermentation to ethanol by the methods of the invention include such sources as hardwoods, softwoods, pulps and sludges from papermaking and other processes, fibrous raw materials derived from agriculture (bagasse, rice fibers, oat hulls, corn stover, wheat straw, bast fibers, and the like) and spent grains and liquors from brewing and distilling operations. Starting materials obtained as a sludge, liquor, or slurry may vary widely in the amount of saccharide present, depending on the industrial process and treatment steps. Solids in paper sludge typically contain from about 7% to about 23% dry material, of which about 68% is cellulose. Cellulose content of complex biological materials can be determined by a combination of extraction and analytic steps that separate cellulose from associated materials (see Updegraff, Analytical Biochem 32:420-4 (1969)). The amount of cellulosic material or other saccharide in the starting material may easily be adjusted by diluting or dehydrating the source material.
B. Pretreatment of Cellulose- and Hemicellulose-containing Materials
Industrial wastes such as pulps and sludges are advantageous in that they often have been subjected to mechanical or chemical processes which increase the bioavailability of cellulose and hemicellulose. For other materials, pretreatment is desirable to increase the accessibility of the polymers to hydrolytic enzymes and to dissociate cellulose, hemicellulose, and lignin components from each other. Pretreatments include mechanical size reduction, heat, steam, steam explosion, chemical pulping, solvent extraction, and various combinations of these separate processes. Sulfur dioxide is often used in combination with autohydrolysis because it gives better sugar yields and helps to modify lignin for subsequent extraction or recovery. Sulfur dioxide combined with steam is particularly effective as a pretreatment for enzymatic cellulose saccharification. In general, the purpose of pretreatment is to maximize subsequent bioconversion yields and minimize the formation of inhibitory compounds; see Cowling & Kirk, Biotech Bioeng Symp 6:95-123 (1975); Wood & Saddler, in Wood & Kellog eds., Methods in Enzymology v. 160, pp. 3-11 (Academic Press, San Diego, 1988).
C. Saccharification
Saccharification is the process of hydrolyzing polymers of the source material, such as cellulose and hemicellulose, or starch, into fermentable mono- and di-saccharides such as cellobiose, glucose, xylose, arabinose, mannose, and galactose. For cellulosics, methods for saccharification include autohydrolysis, acid hydrolysis, and enzymatic hydrolysis.
1. Acid Hydrolysis
Autohydrolysis is the process of converting cellulosic materials into fermentable sugars by exposure to high temperature steam. Many lignocellulosic materials contain significant quantities of acetylated hemicellulose. Steam releases these in the form of acetic acid which subsequently carries out a partial hydrolysis of the hemicellulosic and cellulosic sugars. Sugar yields are generally lower than treatments involving addition of exogenous acids.
Acid hydrolysis is often used as a pretreatment because it can be adapted to a wide variety of feedstocks. Except in the case of strong hydrochloric acid hydrolysis, it is generally carried out at elevated temperature (100 to 240° C.) for various lengths of time. At higher acid concentrations, it can be carried out at temperatures as low as 30° C.
Sulfuric acid can be used in concentrated form, but it is far more commonly used in a dilute solution of 0.5 to 5% sulfuric acid (on a w/w basis with dry solids). The concentrated form usually employs a method of separating and recycling the acid catalyst limiting the total acid losses to approximately 3%, or the same as the dilute process. Use of the concentrated acid however, allows lower temperature and pressure hydrolysis with fewer byproducts produced. Concentrated hydrochloric acid (47%) is sometimes used for strong acid hydrolysis because it is relatively easy to recover. Hydrolysis with concentrated hydrochloric acid gives one of the highest sugar yields of any acid hydrolysis process. It is carried out at room temperature. The chief drawback is the difficulty in handling and recovering the hydrochloric acid.
Dilute acid hydrolysis with 1 to 5% sulfuric acid is generally considered the most cost-effective means of hydrolyzing wood and agricultural residues. Yields of hemicellulosic sugars can be 80 to 95% of theoretical. Yields of glucose from cellulose are generally less than 50% but can approach 55% at elevated temperatures. Percolating and two-step dilute acid processes are suitable for yielding fermentable sugars from most materials (see Durbak et al., “Wood”, in Kirk - Othmer Encyclopedia of Chemical Technology 4 th ed ., John Wiley & Sons, New York, 1998).
2. Enzymatic Hydrolysis
Fermentable sugars may also be released from cellulosic materials by enzymatic hydrolysis. In such embodiments, cellulose or hemicellulose is treated with hydrolytic enzymes that release mono- or disaccharides from cellulose or hemicellulose. Typically originating in wood-rotting fungi or bacteria, enzymes may be added as purified polypeptides which possess a single cellulolytic activity, or as complexes or mixtures typically isolated from a wood-degrading organism and comprising several cellulolytic activities residing on different polypeptides. For cellulose, complete cellulase activity usually requires the activity of endo-1,4-β-glucanases, which hydrolyze cellulose chains at random, cellobiohydrolases or exo-1,4-β-glucanases, which remove glucose or cellobiose from the non-reducing end of the chain, and β-glucosidases, which hydrolyze to glucose the short-chain cell oligosaccharides and cellobiose which are released by other enzymes. K. marxianus strains are capable of fermeneting cellobiose directly, so addition of β-glucosidases is not strictly necessary for saccharification. Enzymes liberating fermentable sugars from hemicellulose include xylanases, β-mannases, β-glucosidases, and arabinofuranosidases and arabinogalactases. Where the source material contains starch, amylases are employed to hydrolyze the starch.
Enzymatic saccharification may be performed prior to fermentation, in which case saccharification may proceed at the optimal temperature for the hydrolytic enzymes (e.g., 50° C.). However, simultaneous saccharification and fermentation by yeast is desirable to simplify the procedure. For organisms such as Saccharomyces cerevisiae , saccharification must take place well below optimal temperatures due to the relatively low thermotolerance of the yeast (see Duff et al., Can J Chem Engin 72:1013-1020); for more heat-resistant organisms such as K. marxianus , simultaneous saccharification and fermentation may be carried out closer to the optimum saccharification temperature (e.g., 43-45° C.).
An alternative strategy for enzymatic saccharification is to culture the treated source material with a living organism able to degrade the cellulosic materials to fermentable sugars. Such organisms typically produce hydrolytic enzymes capable of partially or complete breaking down the polymers to fermentable sugars. Co-culture or pretreatment with a cellulolytic organism may be employed to saccharify source materials. In one embodiment of the invention, however, the same organism is employed to hydrolyze the cellulosic material and to ferment the resulting sugars. For example, K. marxianus strain SSSJ-0 is capable of both breaking down cellulose and fermenting the breakdown products. Thus, strains such as SSSJ-0 may employed in single-step saccharification and fermentation procedures without the addition of cellulolytic enzymes, although exogenous enzymes may be added to speed saccharification or to saccharify polymers that the yeast cannot hydrolyze. Such procedures may be carried out under a single set of reaction conditions. Alternatively, the optimal culture conditions (e.g., temperature, pH, osmotic pressure, oxygen concentration, etc.) for saccharification and fermentation may be determined empirically, and each step carried out with maximum efficiency by appropriate adjustment of the medium or culture conditions between the steps.
D. Hydrolysate Fermentation
Once a hydrolysate has been generated, the sugars in the hydrolysate are cultured with a yeast of the invention to yield ethanol. The composition of the hydrolysate will depend on the source material and the completeness with which the cellulosic materials have been hydrolyzed. Hydrolysis of cellulose yields primarily glucose and cellobiose. Hydrolysis of the hemicelluloses will yield various sugars, the predominant forms depending on the ratios of xylan (yielding primarily xylose, arabinose, and small amounts of glucose, galactose, and mannose), glucomannans (yielding primarily glucose, galactose, and mannose) and xyloglucans (yielding primarily glucose, xylose, galactose, and arabinose). Thus, while varying amounts of other components may be present, hydrolysis of lignocellulosic materials will usually yield a mixture of saccharides, comprising the hexoses glucose, galactose, mannose and the disaccharide cellobiose, as well as the pentoses xylose and arabinose. Accordingly, fermentation usually begins with a mixture of hexoses and pentoses in an aqueous medium either present in the starting material (e.g., sludge) or added to dry source materials during pretreatment or saccharification.
Optimal culture conditions may vary depending on the type and concentration of source material and the pretreatment procedure (see Banat et al., World J Microbiol & Biotechnol 14:809-21 (1998) and Singh et al., World J Microbiol & Biotechnol 14:823-34 (1998) for review). Optimal conditions may be determined empirically simply by varying a particular parameter (e.g., carbon source concentration) over a range of values and determining the optimal yield of ethanol for each condition.
Typical conditions for fermentation of hexoses by K. marxianus strain SSSJ-0 are culture at about 43-45° C. in a medium comprising less than about 20% solid material, and supplemented with about 50 mM citrate buffer, pH about 4.5, about 0.25 mM magnesium sulfate, and about 6.7 g/L yeast nitrogen base. Minerals, vitamins and other small organic molecules, and supplemental carbon sources may be added to the culture medium to promote growth, fermentation, or ethanol tolerance. Other convenient sources of nitrogen compounds known in the art to support yeast growth and fermentation may be employed, e.g., corn steep liquor or diaminophosphate.
To provide an inoculum for the fermentation vessel, seed cultures of yeast are typically generated by overnight growth and added in mid-log phase at a dilution of 1:50, although other culture dilutions may be suitable depending on fermentation conditions and reactor design. The seed culture may be grown in a medium comprising a particular carbon source (e.g., xylose or carboxymethylcellulose) in order to induce hydrolytic or fermentative enzymes prior to inoculation in the fermentation vessel (see, e.g., Jeffries et al., Biotechnol Bioengin 31:502-506 (1988)).
Standard fermentation vessels and systems for yeast culture are suitable for fermentation of plant saccharides. As carbon dioxide production will affect the pH of the culture medium, pH of the culture may be maintained at about 4.5 by typical fermentation methods, e.g., automatic addition of acid or base triggered by a pH sensor. Fermentation may take place aerobically or anaerobically. Anaerobic fermentations may ultimately yield less ethanol, but in applications where the heat generated by fermentation is problematic, anaerobic fermentation is preferred. A period of aerobic growth may be desirable to rapidly increase cell mass before anaerobic fermentation begins. Anaerobic conditions may be obtained by removing oxygen from the medium prior to culture, or simply by sealing the culture vessel and allowing the yeasts to naturally exhaust the oxygen supply. In either circumstances, culture vessels are typically vented to relieve pressure generated from carbon dioxide buildup during fermentation.
In some embodiments, the hydrolysate is fermented in a closed system without removal of biomass or fermented medium, e.g., batch or batch-fed culture systems. Under these circumstances, fermentation typically proceeds until the sugar supply is exhausted or until the buildup of ethanol terminates fermentation. In batch-fed systems, new medium and, optionally, yeast, may be added to continue fermentation. Ethanol tolerance depends on strain background, medium composition, and temperature, but is typically about 8% for K. marxianus before the ethanol production rate begins to decline (see Banat et al., World J Microbiol & Biotechnol 14:809-21 (1998)).
Hydrolysate fermentation may also take place in a variety of bioreactor systems. In one embodiment, fermentation takes place under steady-state culture conditions, in which carbon sources are added and ethanol and cells removed from the culture vessel at constant rates such that the composition of the culture medium remains unchanged. The advantage of such systems is that inhibitory effects of high sugar and ethanol concentrations may be avoided. However, where the cells divide slowly under fermentative conditions, maintenance of the culture biomass may be difficult. Accordingly, a variety of immobilized cell bioreactors may be employed. In such bioreactors, the biomass of cells remains in the reactor, but a constant influx of hydrolysate and removal of ethanol by medium circulation keeps culture conditions constant. For K. marxianus , flocculent strains may be readily isolated, and simple bioreactors which recycle cells by natural sedimentation of flocculating yeast may be employed (see Teixeira et al., Bioprocess Engin 5:123-7 (1990)). Alternatively, yeasts may be immobilized in or on solid supports such as calcium alginate beads, kissiris, polyvinyl alcohol cryogels, or porous ceramics, and incorporated into continuous or fed batch bioreactor designs (see Banat et al., World J Microbiol & Biotechnol 14:809-21 (1998); Singh et al., World J Microbiol & Biotechnol 14:823-34 (1998)). Finally, yeast may be immobilized on a variety of reactor surfaces by formation of biofilms, thereby maximizing the surface area available for interaction of the biomass and culture medium.
The progress of fermentation or hydrolysis may be monitored by measuring the total or reducing sugar content of the hydrolysate, measuring the carbon dioxide evolved by the culture, or by measuring the amount of ethanol in the medium. Ethanol present in the fermentation medium may be measured by physical (e.g., by HPLC or gas chromatography) or enzymatic techniques (e.g., alcohol dehydrogenase and NAD; see Bernt & Gutmmann, in Bergmeyer, ed., Methods of Enzymatic Analysis 2d ed., pp. 1499-1502. Academic Press, NY (1974)). Fermentation may be quantified by determining the ethanol concentration at a fixed time point or when fermentation ceases, or by measuring the initial or steady-state rate of ethanol production. Once the desired quantity of ethanol has been generated, it may be recovered or extracted from the medium by ordinary means (e.g., distillation, extraction, membrane separation, or water adsorption).
EXAMPLES
The following examples are offered to illustrate, but not to limit the claimed invention.
Example 1
Isolation of Strain SSSJ-0 by Enrichment Culture from Recycled Paper Sludge
Recycled paper sludge was obtained from the Smurfit-Stone Container Corporation, Santa Clara, Calif. A sample of the sludge (0.4 g) was inoculated into an enrichment culture medium composed of 50 mM citrate buffer, pH 4.5, 20 percent glucose, 2 percent peptone, and 1 percent yeast extract. The culture was maintained at 45° C. in a shaking water bath (100 rpm) for 18 hours. An aliquot of the enrichment culture was then spread onto plates of YPD, a medium composed of 1 percent yeast extract, 2 percent peptone, 2 percent glucose, and 2 percent agar. The plates were cultured at 43° C. for 18 hours, by which time single colonies of yeast appeared. A single yeast colony was picked and propagated on YPD plates as strain SSSJ-0.
Example 2
Identification of Strain SSSJ-0 as a Variant of Kluyveromyces marxianus
The yeast strain recovered by the enrichment method was identified by sequencing the D1/D2 region of the 18S ribosomal DNA (Kurtzman & Robnett, Antonie van Leeuwenhoek 73:331-371 (1998)). Genomic DNA was extracted from a ˜1 mm 2 colony of the sample using a chelex resin (Walsh et al., Biotechniques 10:506-513 (1991)). The D1/D2 region of the 18S ribosomal DNA was amplified by the polymerase chain reaction (PCR) using the primers NL-1(5′-GCATATCAATAAGCGGAGGAAAAG) and NL-4 (5′-GGTCCGTGTTTCAAGACGG). The PCR was performed with Taq DNA polymerase (Promega), using the conditions recommended by the manufacturer, in a PTC-200 thermal cycler (MJ Research). PCR products were visualized on a 1% agarose (SeaKem) gel and cleaned using a PCR purification kit from Qiagen. Cleaned PCR products were sent for automated DNA sequencing at Davis Sequencing LLC. The amplification products had the sequence shown in SEQ ID NO: 1. Based on this sequence, the strain of yeast was identified as K. marxianus using CLUSTALW alignment with yeast DNA sequences obtained from Genbank (http://www.ncbi.nlm.nih.gov/).
Example 3
Growth of Strain SSSJ-0 on Plant Saccharides
Seed cultures of SSSJ-0 were grown at 43° C. in a liquid medium composed of 20 g/L glucose, 0.67 g/L yeast nitrogen base, and 0.25 mM magnesium sulfate in a 50 mM citrate buffer, pH 4.5. Mid-log aliquots of the seed culture were inoculated (1:50) into test media of identical composition but containing 20 g/L of the carbon source instead of glucose. The amount of carbon source in the recycled paper sludge was estimated by determining the cellulose content of a dried sample. The cultures were maintained at 43° C. in shaking water baths (100 rpm). The increase in cell number was determined by measuring the OD600 of the cultures, or, in the case of the insoluble cellulosics, by plating aliquots of the culture on YPD plates and scoring the number of colonies developed. The doubling time of SSSJ-0 was determined by plotting the number of cells as a function of time in culture.
Carbon Source
Doubling Time (hours)
Glucose
4.0
Arabinose
4.5
Xylose
7.5
Galactose
4.0-4.5
Mannose
4.0-4.5
Cellobiose
3.5
Carboxymethylcellulose
4.0
AVICEL ™
10.0
SIGMACELL ™
10.0
Recycled paper sludge
6.0
Example 4
Growth of Strain SSSJ-0 on Various Carbon Sources
Seed cultures of SSSJ-0 were grown and inoculated into media containing (1) 2% glucose and 2% L-arabinose; (2) 2% lignin +/−0.67 g/L yeast nitrogen base (Fisher); (3) 2% corn stover hydrolysate +/−0.67 g/L yeast nitrogen base; (4) 2% xylose; and (5) 2% SIGMACELL® or 2% AVICEL®, according to the method of Example 3. The increase in cell number was determined by measuring the OD600 of the cultures, or, in the case of the SIGMACELL® (Sigma) and AVICEL® (Fluka), by plating aliquots of the culture on YPD plates and scoring the number of colonies developed. Results of SSSJ-0 growth on 2% glucose and 2% L-arabinose are shown in FIG. 2 . Results of SSSJ-0 growth on lignin +/− yeast nitrogen base are shown in FIG. 3 . Results of SSSJ-0 growth on corn stover hydrolysate +/− yeast nitrogen base are shown in FIG. 4 . Results of SSSJ-0 growth on xylose are shown in FIG. 5 . Results of SSSJ-0 growth on SIGMACELL® or AVICEL® are shown in FIG. 6 .
Example 5
Production of Ethanol by Fermentation of Plant Saccharides
Seed cultures of SSSJ-0 were grown and inoculated into media containing plant saccharides according to the method of Example 3, except that the test cultures were grown in air-tight serum bottles to promote anaerobic fermentation. After 48 hours, an aliquot of the medium was withdrawn and enzymatically assayed for ethanol content by incubation with alcohol dehydrogenase and NAD.
Carbon Source
Ethanol (mg/L)
Glucose
67.0
Arabinose
4.6
Xylose
6.4
Galactose
21.2
Mannose
18.9
Cellobiose
3.9
Carboxymethylcellulose
4.6
AVICEL ™
2.0
SIGMACELL ™
6.1
Brewers spent grain (wet)
5.0
Recycled paper sludge
6.1
Example 6
Production of Ethanol from Paper Sludge by Enzyme-free Simultaneous Saccharification and Fermentation
Paper sludge was obtained from a plant in Ohio. Seed cultures of SSSJ-0 were grown overnight in citrate buffer, pH 4.5 with yeast nitrogen base, magnesium sulfate, and 2% carboxymethylcellulose. The seed culture was inoculated at a dilution of 1:500 into 20 ml of a culture medium composed of citrate buffer with yeast nitrogen base, magnesium sulfate, and sludge containing about 350 mg of cellulose. The culture was grown in an air-tight serum bottle at 43° C. in a shaking water bath. After 48 hours, an aliquot of the medium was removed and assayed for ethanol content with alcohol hydrogenase and NAD. The aliquot contained 125 mg/L of ethanol.
It is understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes. | This invention relates to the use of microorganisms for the generation of ethanol from lignocellulosic waste materials. Yeast strains of the genus Kluyveromyces which have the capability to ferment cellulose, hexose sugars to ethanol are provided. Also provided are methods for converting cellulose, hexoses, or mixed hydrolysates of hexoses to ethanol by fermentation with Kluyveromyces strains. The invention also provides methods to isolate yeast strains which metabolize cellulose, pentoses, or hemicelluloses from waste materials. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to windows and more particularly to a single-hung window that simultaneously incorporates the use of a lower screen member with a vertically positionable lower sash without revealing the operating features for either the lower screen member or the &lower sash member to an observer who is standing in front of the exterior face of the window.
2. Description of the Prior Art
A common window design found within early 20 th century and older homes provided a simple removable window frame having a pair of horizontally spaced side jambs, a head jamb located at the upper end of the side jambs, a sill disposed at the lower end of the side jambs and a meeting rail extending between the side jambs intermediate the head jamb and sill. The window frame formed upper and lower window openings that were covered with glass panes or screens. Accordingly, two separate windows were required for year round use with this window design. When the weather turned cold or stormy, the window having glass panes disposed within the window openings would be used. As the weather became warm in the Spring and Summer months, the glass-paned window would be removed and stored while a completely separate window, having screens in place of the window panes would be positioned in its place. Accordingly, the window design proved to be tedious during the Fall and Spring seasons when the homeowners might want to exchange one lower sash for the other as the temperatures and weather conditions varied back and forth.
Another flaw in the window design prevented the homeowner from varying the degree in which the window was opened. Unlike the convenient single or double-hung windows currently being used, the historic storm window was either open or closed. Moreover, regardless of whether the window is opened or closed, the homeowner had to store the window that was not being used. While this is not a serious inconvenience for a single window, it was common for a home to have several windows on each floor that would have a counterpart window that had to be stored. Accordingly, a homeowner may have to store ten or more complete window units at any given time.
The restoration of historic homes, as well as the construction of new homes having historic exterior designs, has become a growing industry and popular cultural trend. Oftentimes, the windows must be restored or replaced. What is needed is a window design that provides a replacement window for historic structures that resembles the exterior appearance of the structure's original windows, but also provides several of the conveniences found within modern single-hung windows. Moreover, the novel window design should provide a manner in which an existing window within a historic structure can be restored to include basic modern conveniences while retaining some of its historic exterior appearance.
SUMMARY OF THE INVENTION
The window design of the present invention is first provided with a window frame having a pair of vertical jambs coupled with a head jamb, meeting rail and lower rail. In a preferred embodiment, an upper sash is secured in a fixed position between the vertical jambs, the head jamb and the meeting rail. A pair of interior jambs are provided to extend outwardly from an interior face of each vertical jamb. In a preferred embodiment, an interior lower rail is provided to extend outwardly from an interior face of the window frame lower rail. A lower sash having upper and lower rails and opposing stiles is provided to slide within the interior jambs between open and closed positions.
In one preferred embodiment, weatherstripping is coupled to the interior jambs and the interior lower rail to resist the infiltration of the elements and to provide a snug fit for the lower sash as it is moved between its open and closed positions. In another preferred embodiment, a pair of latch pins are provided at the lower end portion of the lower rail to provide a means with which the user can secure the lower sash in one of a plurality of different vertical positions along the lengths of the interior jambs. The interior jambs and lower rail may be anchored within channels formed in the interior faces of the window frame using press-fit anchors that extend outwardly from the interior jambs and lower rail. A screen panel may be secured within the exterior face of the window frame to provide simultaneous use of the lower sash and the screen panel.
It is therefore one of the principal objects of the present invention to provide a window design that resembles a historic storm window while permitting the simultaneous use of a lower sash and a screen panel.
A further object of the present invention is to provide a window design that provides a lower sash that is vertically slid between open and closed positions while retaining a historic exterior appearance.
Still another object of the present invention is to provide a window design that resembles a historic storm window but provides a vertically sliding lower sash that substantially prevents the unintended infiltration of the wind and elements.
Yet another object of the present invention is to provide a window design having an exterior appearance that is similar to a historic storm window while providing a vertically moveable lower sash and increasing the torsional stability and trueness of the window frame.
Still another object of the present invention is to provide a method of restoring a historic storm window which incorporates the convenience of a sliding lower sash while generally retaining the historic exterior appearance of the window.
A further object of the present invention is to provide a window design that enables an individual to modify an existing historic storm window to include a permanent screen panel and a sliding lower sash without departing greatly from the historic exterior appearance of the window.
These and other objects of the present invention will be apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of the exterior face of one embodiment of the window of the present invention;
FIG. 2 is an isometric view of the interior exterior face of one embodiment of the window of the present invention;
FIG. 3 is a partial sectional view of one embodiment of the window of the present invention;
FIG. 4 is a partial exploded view of one embodiment of the window of the present invention;
FIG. 5 is a partial view of the window of the present invention with the lower sash in an open position; and
FIG. 6 is another partial view of the window of the present invention with the lower sash in an open position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The window 10 of the present invention is generally depicted in FIGS. 1–6 and is described herein as a single-hung design. However it is contemplated that the design of the window 10 would easily permit its construction as a double-hung window, in those particular circumstances where such a design would be desirable. For ease of description, the window 10 is described as a replacement or new construction window, it will be clear to those having skill in the art that the structures and principles of the window 10 could be easily applied in modifying existing historic or modern windows.
The window 10 is provided with a window frame 12 having a first vertical jamb 14 and a second vertical jamb 16 that are spaced horizontally from one another. A head jamb 18 is coupled to the upper end portions of the first and second vertical jambs 14 and 16 . A meeting rail 20 extends between the first and second vertical jambs 14 and 16 intermediate their upper and lower end portions. A lower rail 22 is coupled to the lower end portions of the first and second vertical jambs 14 and 16 . In a preferred embodiment, an upper sash 24 is secured in a fixed position between the first and second vertical jambs 14 and 16 and the head jamb 18 and meeting rail 20 . The first and second vertical jambs 14 and 16 combine with the meeting rail 20 and lower rail 22 to define a window opening 26 . Stylistically, the window frame 12 could be provided in various shapes and in a wide range of dimensions. For example, the window frame 12 may be crafted to closely resemble a window frame from a historic storm window that exhibits a particular period appearance. Hardware, such as the hangers 27 depicted in FIGS. 1 and 2 , may be used to selectively removably secure the window 10 within the opening of a window casing.
In a preferred embodiment, first and second interior jambs 28 and 30 extend outwardly from interior faces 32 and 34 of the first and second vertical jambs 14 and 16 . In this manner, the first and second interior jambs would extend into the room of the building to which the window 10 is secured. The first and second interior jambs 28 and 30 are shaped to provide channels 36 and 38 that extend along at least a portion of the length of the first and second interior jambs 28 and 30 . The channels 36 and 38 are positioned within the first and second interior jambs 28 and 30 to generally face one another in a coplanar manner so that they may slidably receive the side portions of a lower sash 40 . In its preferred embodiment, the lower sash 40 is provided with a glass pane 42 that is framed by upper and lower rails 44 and 46 and first and second stiles 48 and 50 . It is contemplated that such rails and stiles may be comprised of structures separate and apart from the glass pane 42 and formed from nearly any material such as various metals, woods and polymers. However, it is also contemplated that the rail and stile portions of the lower sash 40 could simply be the peripheral ledge portions of the glass pane 42 itself in particular applications. Regardless, the lower sash 40 is selecting moveable within the channels 36 and 38 between open and closed positions.
An interior lower rail member 52 may be provided to extend outwardly from an interior face 54 of the window lower rail 22 . The interior lower rail member 52 is shaped to have a channel 56 extending along at least a portion of its length, much in the same manner as the channels 36 and 38 are formed within the first and second interior jambs 28 and 30 . The channel 56 preferably faces in a generally upward direction and positioned in a coplanar manner with the channels 36 and 38 so that at least a portion of the lower rail 46 of the lower sash 40 is received within the channel 56 when the window 10 is in a closed position.
Due to the advent of various extruded materials and precise shaping processes, it is contemplated that the lower sash 40 will be slidably received within the channels 36 , 38 and 56 in such a manner that wind and other weather elements are substantially prevented from passing there between. Moreover, the first and second interior jambs 28 and 30 and interior lower rail member 52 should be formed from various modern materials that are durable while exhibiting low coefficients of friction for smooth and easy manipulation of the lower sash 40 over the lifetime of the window 10 . However, lengths of weatherstripping 58 can be provided where the lower sash 40 engages the first and second interior jambs 28 and 30 , the interior lower rail member 52 and the meeting rail 20 to further ease the sliding action. In one embodiment, the lengths of weatherstripping 58 are secured along a portion of the channels 36 , 38 and 56 , as well as the meeting rail 20 using an adhesive or other structural securement means, such as tacks and the like. Similarly, the lengths of weatherstripping 58 can be adhered to the upper and lower rails 44 and 46 and the first and second stiles 48 and 50 of the lower sash 40 to achieve a similar sealing engagement with the channels 36 , 38 and 56 . A mounting plate 60 may be secured to the meeting rail 20 to receive a length of weatherstripping 58 .
In a preferred embodiment, slots 62 are formed along channels 36 , 38 and 56 as well as the mounting plate 60 . The slots 62 should be shaped to receive the rearward surface of the particular type of weatherstripping being used. For example, common felt weatherstripping is provided with a narrow strip of backing material that is easily disposed within T-shaped slots and are easily secured in their positions, with or without adhesives, due to the structural mating of the T-shaped slots and the weatherstripping. A nearly limitless number of different shapes, such as dovetail, elliptical, and the like could be incorporated with the slots 62 depending on the particular application and type of weatherstripping being employed. Such design flexibility is desirable due to the wide range of available materials that would suffice for use in constructing the lengths of weatherstripping 58 , such as rubber, polymers, synthetic materials and various combinations thereof.
Where the window 10 is provided as a new or replacement window, it is contemplated that the first and second interior jambs 28 and 30 and the interior lower rail member 52 could be integrally formed with their respective first and second vertical jambs 14 and 16 and window lower rail 22 whether the structural components are formed from metal, wood, plastic or various combinations thereof. However, in many cases the first and second interior jambs 28 and 30 and interior lower rail member 52 will be separate parts that are secured to the interior faces of the first and second vertical jambs 14 and 16 and window lower rail 22 . The method of securement will depend upon the particular application. While various adhesives are contemplated, conventional fasteners, such as nails and screws may be preferred. However, in one preferred embodiment, shaped anchors 64 can be provided to extend outwardly from the mounting surfaces of the first and second interior jambs 28 and 30 and the interior lower rail member 52 so that they are secured within anchor recesses 66 formed within the interior faces of the window frame 12 . It is contemplated that the shapes of the anchors 64 can vary greatly from those depicted in the Figures. However, shapes that permit the anchors 64 to be press-fit within the anchor recesses 66 , while resisting extraction, are preferred. Similarly, while the anchor 64 could be provided as an elongated, continuous member that is received within a channel-shaped anchor recess 66 , it is contemplated that the anchor 64 could be more prong-shaped and received within a smaller individual anchor recess. An added benefit to the use of the separate first and second interior jambs 28 and 30 and the interior lower rail member 52 is an increase in the torsional stability and trueness of the first and second vertical jambs 14 and 16 and the window lower rail 22 over the life of the window 10 . This structural bracing is provided without a dramatic increase overall structural weight or complexity.
An optional screen member 68 may be simultaneously incorporated with the use of the lower sash 40 . In a preferred embodiment, a peripheral edge portion 70 of the screen member 68 is disposed within channels 72 that are formed within the exterior faces 74 and 76 of the first and second vertical jambs 14 and 16 and the exterior faces 78 and 80 of the meeting rail 20 and window lower rail 22 . An elongated spline 82 may be used to secure the peripheral edge portion 70 of the screen 68 within the channels 72 . To provide a finished appearance to the exterior of the window 10 , molding 84 can be applied above the spline 82 to closely resemble the molding or glazing used on the adjacent upper sash 24 .
Several different means for securing the lower sash 40 in one of several different open positions and a closed position may be provided. In a preferred embodiment depicted in FIG. 6 , a pin member 86 extends outwardly from each of the first and second stiles of the lower sash 40 . The pin members 86 should be slidably engageable with a plurality of openings 88 formed within the channels 36 and 38 in the first and second interior jambs 28 and 30 . The openings should be positioned in opposing pairs along the lengths of the channels 36 and 38 at a closed position and one or more open positions where the lower sash 40 is disposed in different open positions that reveal varying degrees of the window opening 26 . In a preferred embodiment, the pin members 86 are each operatively connected to tabs 90 that may be selectively grasped by a user to manipulate the pin members 86 into and out of engagement with the openings 88 . The tabs 90 also provide an optional structure with which the user may lift and pull the lower sash 40 between open and closed positions. It is contemplated that the pin members 86 could be outwardly biased by springs to assist the user in locating the openings 88 .
The design of the window 10 presents few changes to the exterior appearance of the window being replaced or remodeled. To further enhance the exterior appearance of the window 10 , a shaped profile 92 , such as an ogee may be formed along the peripheral edge of the window opening 26 , adjacent the first and second interior jambs 28 and 30 , as well as the interior lower rail member 52 and the mounting plate 60 to provide the optical illusion that the lower sash 40 is not actually disposed behind the window frame 12 . Accordingly, when the exterior of the window 10 is viewed at various angles, it appears as though the lower sash 40 is disposed within the window opening 26 in a manner similar to historic storm windows.
In the drawings and in the specification, there have been set forth preferred embodiments of the invention and although specific items are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and proportion of parts, as well as a substitution of equivalents, are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims.
Thus it can be seen that the invention accomplishes at least all of its stated objectives. | A window design is provided with a pair of vertical jambs, a head jamb, a meeting rail and a sill. In one embodiment, an upper sash is secured in a fixed position between the vertical jambs, head jamb and meeting rail. Interior jambs are provided to extend outwardly from interior faces of the window frame and slidably receive a lower sash that is selectively moved between open and closed positions. A screen may be optionally secured to the exterior face of the window frame to allow the simultaneous use of the screen and the sliding lower sash. The window design retains a historic exterior appearance of the window while providing improved conveniences and durability. | 4 |
FIELD OF INVENTION
[0001] The present invention relates to aripiprazole medicament formulation and preparation method therefor.
PRIOR ARTS
[0002] Aripiprazole whose chemical name is 7-[4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butoxy]-3,4-dihydro-2(1H)-quinolinone, belongs to quinolinone derivatives, and was approved by the FDA in November, 2002 for the treatment of schizophrenia.
[0003] Aripiprazole is a water-indissolvable medicament, and only a certain level of fineness of it can ensure quick dissolution, absorptivity and bioavailability of the prepared preparation. For example, the average particle size can just reach about 100 micron when an universal pulverizer is used to pulverize the aripiprazole mechanically and the dissolution characteristic of the prepared preparation is still not ideal. Besides, the process of mechanical pulverization also has the problems of dust, environmental pollution, and great loss etc. And due to the high activity of aripiprazole, it is easy to cause adverse reactions for the operators if inhaling or touching the aripiprazole powder.
[0004] For now, processes for reducing the particle size of the aripiprazole through non-mechanical treatment has been reported in some references. Such as that a chinese patent application (publication number: CN1871007) has disclosed a method for preparing the sterile grain of aripiprazole with an average particle size less than 100 micron by the impact jet crystallization which is used to prepare a sterile freezed dried aripiprazole formulation, and also an injectable aripiprazole aqueous suspension formulation. The chinese patent application (publication number: CN101172966A) has disclosed a method for preparing microcrystal of type I crystal of aripiprazole, which includes heating the crude product of aripiprazole and ethanol of about 10 times the amount of aripiprazole to reflux for dissolution, adding low-temperature water and cooling rapidly when stirring, filtrating, washing and drying the precipitated crystals, and then mixing the gained microcrystal of aripiprazole with excipients to obtain formulation. But the above-mentioned operation is relatively complicated, has a great loss and high cost, and when preparing the formulation by mixing the microcrystal with excipients, there still exists issues of dust and high labor protection requirements.
[0005] In addition, to a formulation, it also needs to consider whether some performance indicators are excellent or not, such as stability, solubility and the amount of the related substances contained in formulation etc.
[0006] Therefore, for an aripiprazole medicament formulation, it is urgent to seek a preparation method of the aripiprazole formulation which can not only overcome the defects of the existing method mentioned above, but ensure various excellent performances as well.
Content of the Present Invention
[0007] The technical problem to be solved in the present invention is that for overcoming the defects which includes dust, serious security risks, complicated operation, high cost, pollution and great loss of the existing preparing method of the aripiprazole medicament formulation, a preparation method of the aripiprazole medicament formulation and the formulation gained by this method have been provided. The method has no security risks, simple operation, less pollution and loss, low cost, good process control, and can obtain the formulation with excellent solubility, stability and less amount of related substances.
[0008] To solve the technical problems above, the inventor specially adopts the technology called “Acid-Base Solventing-out Dispersion” (A-BsoD) which includes dissolving the aripiprazole with acidic solution, and then performing the wet granulation with the medicament having acidic solution, alkalizer and excipients which contain antioxidant, restoring aripiprazole to a solid state in the process of granulation, combining the process of dispersing the microcrystal of insoluble medicaments and excipients with wet granulation or preparation of suspension. The method can not only overcome the defects mentioned above in the prior art, but it is worth mentioning that the aripiprazole formulation prepared by this method also has excellent solubility, stability, especially less amount of related substances. The inventor of the present application also discovered that the method has excellent controllability unexpectedly, which means that the aripiprazole formulation with required particle size can be made artificially controlled by utilizing the regular change between the particle size of aripiprazole contained in the obtained product and the preparing conditions and this is more beneficial to ensuring and controlling the solubility of aripiprazole formulation.
[0009] Specifically, the invention achieved the above technical effects by the following technical solutions:
[0010] The present invention relates to a method for preparing an aripiprazole medicament formulation, which comprises the following steps: dissolving aripiprazole in an acidic solution having an acidifier so as to obtain a medicament having acidic solution; then, performing a wet granulation on or preparing a suspension with the obtained medicament having acidic solution, an alkalizer, and an excipient so as to obtain the aripiprazole medicament formulation; the said excipient comprising an antioxidant.
[0011] In the present invention, the said aripiprazole is an active pharmaceutical which is water-indissolvable and weakly alkaline, and the dosage of which can be determined according to the conventional amount of aripiprazole contained in a formulation. If the solid preparation was prepared by wet granulation, the mass of aripiprazole usually counts 1%˜20% the mass of the dry materials of wet granulation, preferably 2%˜15%. If the formulation is a suspension, the mass of aripiprazole is usually 0.01%˜1% the mass of the suspension, preferably 0.05%˜0.2%. According to the need, in addition to the aripiprazole, other active pharmaceutical ingredients can also be added for preparing the compound preparations of aripiprazole. The said other active pharmaceutical ingredients can be used in combination and have no adverse effects with the aripiprazole.
[0012] In the present invention, the said acidifier refers to the acid reagent that can make the aripiprazole completely dissolved in the acidic solution having an acidifier. According to the common knowledge in the art, the said acidifier should be pharmaceutically acceptable and compatible with the aripiprazole. In the present invention, the said compatibility means coexistence without adverse effects. The said acidifier can be a single acidifier as well as a compound acidifier consisting of more than two components, which can be selected from a variety of acids, such as one or more among inorganic strong acid, inorganic mediate strong acid and organic weak acid, preferably selected from one or more among hydrochloric acid, citric acid, malic acid, lactic acid, hydrobromic acid, nitric acid, sulfuric acid, fumaric acid, succinic acid, maleic acid, acetic acid and phosphoric acid, and more preferably hydrochloric acid, citric acid, lactic acid and malic acid, and the most preferably from hydrochloric acid, or hydrochloric acid and citric acid. The dosage of the said acidifier is at least the minimum dosage which can completely dissolve the aripiprazole, preferably 1˜1.2 times the minimum dosage, more preferably 1˜1.05 times the minimum dosage. The said minimum dosage refers to the minimal dose of a certain acidifier which can just make the aripiprazole dissolved under the preparation conditions of the same solvent and medicament having acidic solution, and the said minimum dosage can be obtained by simple conventional method: under the preparation conditions of the same solvent and medicament having acidic solution, the minimum dosage is determined by increasing the acidifier's dosage gradually until when the aripiprazole is just dissolved. It has been concluded by many experiments that when the acidifier is hydrochloric acid, the molar ratio of the hydrochloric acid to the aripiprazole is generally 0.9˜1.2, preferably 0.95˜1.1, more preferably 0.98˜1.05. When the acidifier is hydrochloric acid and citric acid, the molar ratio of the hydrochloric acid and citric acid to the aripiprazole is generally 0.9˜1.2, preferably 0.95˜1.1, and more preferably 0.98˜1.05.
[0013] In the present invention, the solvent of the said acidic solution having an acidifier may be organic solvent, or a mixture of water and organic solvent, preferably the mixture of water and organic solvent. The said organic solvent is selected from the acceptable solvents in the pharmaceutical field according to the principle that the solubility of the aripiprazole in this organic solvent is better than that in water, and the water-miscible organic solvent is preferred, such as conventionally used water-soluble alcohols in the pharmaceutical field, like ethanol, propylene glycol, glycerin, isopropyl alcohol and tertiary butyl alcohol etc., preferably one or more among ethanol, propylene glycol and glycerol, and ethanol in particular. The dosage of the organic solvent can be selected optionally in the mixture of water and organic solvent. When using aqueous ethanol solution, the concentration of ethanol is preferably 40 wt % or more, more preferably 60 wt % or more. In the present invention, there is no particular requirement to the solvent dosage of the said acidic solution having an acidifier. In generally, the solvent dosage of the acidic solution having an acidifier is at least able to make the aripiprazole completely dissolved and the subsequent of wet granulation or a suspension can be performed, which is usually 2 times the mass of aripiprazole or more, preferably 3˜4 times.
[0014] Before an alkalizer is added, some other excipients can be added as well, such as one or more among surfactants, solubilizers, the water-soluble carriers and disintegrants etc., then subsequent steps are carried out with the gained medicament having acidic solution or the mixture of the medicament having acidic solution and the above-mentioned excipients, that is wet granulation or preparing a suspension with the alkalizer and excipients. These excipients can be added during or after the preparation of the medicament having acidic solution, and the order of addition is related to miscibility of these excipients and the medicament having acidic solution. The excipients that can be miscible with the medicament having acidic solution and allow the medicament having acidic solution maintaining in solution state rather than forming a turbid liquid or a viscous liquid could be added during or after the preparation of the medicament having acidic solution, while the excipients which can not be miscible with the medicament having acidic solution and can make the medicament having acidic solution transform into a turbid liquid or a viscous liquid from the solution state are usually required to be added after the medicament having acidic solution is prepared. Generally, the said surfactants and/or the solubilizers can be added during or after the preparation of the medicament having acidic solution; the said water-soluble carriers and/or disintegrants are required to be added after the preparation of the medicament having acidic solution, except for the water-soluble carriers which can dissolve in the medicament having acidic solution (such as polyethylene glycol and hydroxypropyl-β-cyclodextrin). If the said water-soluble carriers are added during the preparation of the medicament having acidic solution, the dosage of water-soluble carriers should be lower than the dosage which can ensure the aripiprazole completely dissolve in the acidifier-containing acid solution and then, the water-soluble carriers and/or disintegrants can still be added after the addition of said dosage of water-soluble carriers, and when a large addition is involved, the gained mixture of medicament having acidic solution and excipients would be in the form of a turbid liquid or a viscous liquid. The said surfactants and/or solubilizers in the present invention prefer one or more among povidone, sodium dodecyl sulfate, poloxamer, polyoxyethylenated castor oil, Tween 80 and polyoxyl (40) stearate, more preferably one or more among povidone, sodium dodecyl sulfate, poloxamer and Tween 80. The said water-soluble carriers in the present invention prefer one or more among lactose, mannitol, sucrose, polyethylene glycol (preferably polyethylene glycol 400-8000), hydroxypropyl-β-cyclodextrin, β-cyclodextrin and maltitol, more preferably one or more among lactose, mannitol, polyethylene glycol 6000, hydroxypropyl-β-cyclodextrin and sucrose. The said disintegrants in the present invention prefer one or more among sodium carboxymethyl starch, hydroxypropyl cellulose, cross-linked polyvinylpyrrolidone and crosslinked carboxymethylcellulose sodium, more preferably one or more among sodium carboxymethyl starch, hydroxypropyl cellulose and cross-linked polyvinylpyrrolidone. The dosage of said surfactants and/or solubilizers is preferably 0.01˜2 times the mass of aripiprazole, more preferably 0.02˜1 times. The dosage of said water-soluble carriers is preferably 1˜10 times the mass of aripiprazole. It can increase solubility of aripiprazole in the acidic solution and reduce the solvent dosage when surfactants and/or solubilizers are added according to the above-mentioned procedure, which is beneficial to the subsequent granulation steps. It is especially worth mentioning that it can make the solubility of aripiprazole medicament formulation better when one or more among surfactants, solubilizers and water-soluble carriers, especially water-soluble carriers, is(are) added according to the procedure mentioned above.
[0015] Preferably, during the preparation of the medicament having acidic solution, it is beneficial to the dissolution of aripiprazole when the temperature is appropriately increased through heating (such as using a hot water-bath). Generally, the temperature can be increased to 30˜85° C. When aqueous ethanol solution is used, the temperature is preferably increased to 30˜70° C., more preferably to 40˜65° C.
[0016] In the present invention, the said alkalizer refers to the reagent which can reduce the acidity of the mixture of the alkalizer and the medicament having acidic solution relative to the acidity of the medicament having acidic solution, such as inorganic strong alkali (such as sodium hydroxide or potassium hydroxide), the salt of weak acid and strong alkali (such as sodium carbonate, potassium carbonate and disodium hydrogen phosphate). The said alkalizer can be a single alkalizer as well as a compound alkalizer consisting of more than two components, and the said alkalizer is most preferably sodium hydroxide and/or sodium carbonate. According to the conventional knowledge in this field, the said alkalizer should be pharmaceutically acceptable and compatible with the aripiprazole. The dosage of the said alkalizer is at least the one that can reduce the acidity of the mixture of the alkalizer and the medicament having acidic solution relative to that of the medicament having acidic solution. To prevent the pH value of the system from increasing drastically when the alkalizer is added, the alkalizer, especially inorganic strong alkali such as sodium hydroxide, is preferably added in the form of alkalizer-containing solution. The alkalizer, such as sodium carbonate, is added in the form of alkalizer-containing solution or dispersed uniformly among the other excipients. The concentration of the alkalizer in the alkalizer-containing solution is preferably 5˜20 wt %. The solvent contained in the alkalizer-containing solution can be water or a mixture of water and organic solvent. The said organic solvent is the same as the organic solvent contained in the medicament having acidic solution.
[0017] When the subsequent steps require wet granulation, the total dosage of the solvent contained in the medicament having acidic solution and the solution of said alkalizer should be at least the minimum dosage of the granulating liquid required by wet granulation. Generally, the total dosage of the solvent is 5˜100% the mass of dry materials of wet granulation, and preferably 10˜75%.
[0018] A preferred embodiment of the present invention employs any one of the following groups of acidifier and alkalizer.
[0019] Type 1: the said acidifier is inorganic strong acid, and the said alkalizer is inorganic strong alkali, such as hydrochloric acid and sodium hydroxide. The molar ratio of the sodium hydroxide to the hydrochloric acid is preferably 0.95˜1.05, more preferably 0.99˜1.01. At present, in order to control the pH value of the system better after the alkalizer is added and improve the stability of the formulation, after the preparation of the medicament having acidic solution, before or during the time when the alkalizer is added, a reagent acted as a pH buffer should be added after the alkalizer is added, and the said reagent should be pharmaceutically acceptable. The said reagent can be organic weak acid, such as one or more among citric acid, glycine, tartaric acid, malic acid and acetic acid, also can be all kinds of acid salt such as one or more among sodium bisulfite, sodium sulfite, sodium dihydrogen phosphate, disodium hydrogen phosphate and a conjugate base of organic weak acid such as sodium citrate. The dosage of said reagent is preferably 0.1%˜0.4% the mass of aripiprazole, more preferably 0.5%˜2%.
[0020] Type 2: the said acidifier is inorganic strong acid, and the said alkalizer is the salt of weak acid and strong alkali, such as hydrochloric acid and sodium carbonate, or hydrochloric acid and disodium hydrogen phosphate, preferably hydrochloric acid and sodium carbonate. The molar ratio of the sodium carbonate to the hydrochloric acid or the molar ratio of the disodium hydrogen phosphate to the hydrochloric acid is preferably 0.75˜1.05, more preferably 0.90˜1.01.
[0021] Type 3: the said acidifier is organic weak acid, and the said alkalizer is inorganic strong alkali, such as lactic acid and sodium hydroxide. The molar ratio of the sodium hydroxide to the lactic acid is preferably 0.95˜1.05, more preferably 0.99˜1.01.
[0022] Type 4: the said acidifier is inorganic strong acid and organic weak acid, and the said alkalizer is inorganic strong alkali and/or the salt of weak acid and strong alkali. When the acidifier is hydrochloric acid and citric acid, the said alkalizer is preferably sodium hydroxide, or the combination of sodium hydroxide and sodium carbonate. When the acidifier is hydrochloric acid and citric acid and the said alkalizer is sodium hydroxide, the molar ratio of the sodium hydroxide to the acidifier is preferably 0.95˜1.05, more preferably 0.99˜1.01. When the acidifier is hydrochloric acid and citric acid and the said alkalizer is sodium hydroxide and sodium carbonate, the molar ratio of the alkalizer to the acidifier is preferably 0.95˜1.05, more preferably 0.99˜1.01.
[0023] In the present invention, the said antioxidant can be selected according to the common knowledge in the present field, which can be but not limited to one or more among sodium metabisulfite, sodium bisulfite, sodium sulfite, thiourea, sodium thiosulfate, L-cysteine and sodium ascorbate, water-soluble organic weak acid, the conjugate base of the water-soluble organic weak acid, butylated hydroxyanisole, dibutyl hydroxy toluene, ascorbyl palmitate and propyl gallate etc. The said water-soluble organic weak acid is preferably one or more among citric acid, tartaric acid and malic acid. The said conjugate base of the water-soluble organic weak acid is preferably sodium citrate and/or sodium tartrate.
[0024] Wherein the said antioxidant preferably includes antioxidant which can play a role in buffering in the case that the acidifier or alkalizer is excessed, such as one or more among sodium bisulfite, sodium metabisulfite and sodium sulfite etc. which may play a role in pH buffering in the case that the acidifier or alkalizer is excessed, and the water-soluble organic weak acid, such as citric acid etc., can play a role in pH buffering in the case that the alkalizer is excessed.
[0025] In the present invention, the antioxidant is preferably the sodium bisulfite, sodium metabisulfite, sodium sulfite or sodium thiosulfate in combination with the said water-soluble organic weak acid, or in combination with the said water-soluble organic weak acid and the conjugated base of this water-soluble organic weak acid. The said combination is preferably sodium sulfite in combination with the said water-soluble organic weak acid, or sodium bisulfite, the said water-soluble organic weak acid in combination with the conjugate base of this water-soluble organic weak acid, more preferably the combination of sodium sulfite and citric acid, or the combination of sodium bisulfite, citric acid and sodium citrate.
[0026] The said antioxidant is preferably added after the preparation of the said medicament having acidic solution, and before or during the time when the said alkalizer is added. The dosage of the said antioxidant is preferably 0.1˜100% the mass of aripiprazole. When the solid formulation is prepared by wet granulation, the dosage of the said antioxidant is preferably 0.1˜10% the mass of aripiprazole, more preferably 1˜5% the mass of aripiprazole. When a suspension is prepared, the dosage of the said antioxidant is preferably 10˜100% the mass of aripiprazole.
[0027] In the present invention, the said wet granulation can be carried on according to the conventional granulation steps and conditions belonging to the category of wet granulation in the field, such as extrusion granulation (e.g. extrusion by swing machine, screw extrusion and rotating extrusion etc.), stirring granulation, fluidized spray granulation, centrifugal spray granulation and so on. Stirring granulation and extrusion granulation are preferred. Preferably, the specific mode of operation is selected from anyone of the following methods: method (1) uniformly mixing the medicament having acidic solution with the alkalizer or the alkalizer-containing solution to obtain a granulating solution, and then carrying on extrusion granulation, stirring granulation, fluidized spray granulation or centrifugal spray granulation with the granulating solution and the excipients to obtain the solid preparations; method (2) uniformly mixing the medicament having acidic solution with the excipients, and then uniformly mixing them with the alkalizer or the alkalizer-containing solution, and carrying on extrusion granulation or stirring granulation to obtain the solid preparations; method (3) uniformly mixing the alkalizer or the alkalizer-containing solution with the excipients, and then uniformly mixing them with the medicament having acidic solution, and carrying on extrusion granulation or stirring granulation to obtain the solid preparations; method (4) uniformly mixing the medicament having acidic solution, the excipients whose dosage are below one-third with the alkalizer or the alkalizer-containing solution, and then mixing them with the left excipients and carrying on extrusion granulation or stirring granulation to obtain the solid preparations. In the methods mentioned above, the said solid preparations can be solid particles preparations, also can be tablets (including the oral disintegrating tablets of aripiprazole), dry suspensions or capsules etc. and other forms of solid preparation of aripiprazole.
[0028] In the present invention, when the solid particles preparation of aripiprazole is prepared by wet granulation, the said excipients can be selected from any known and widely used excipients in this field, such as fillers. When tablet or capsule of aripiprazole is prepared by wet granulation, the said excipients can be selected from any known and widely used excipient in this field, such as fillers, disintegrants, lubricants and so on. When dry suspension of aripiprazole is prepared by wet granulation, the said excipients can be selected from any known and widely used excipients in this field, such as suspending agents and lubricants. The said fillers can be the fillers that are conventionally used in this preparation field, preferably one or more among lactose, microcrystalline cellulose, pregelatinized starch, starch, mannitol, sucrose and maltitol. The said disintegrants can be the disintegrants that are conventionally used in this preparation field, preferably one or more among carboxymethyl starch sodium, hydroxypropyl cellulose, cross-linked polyvinylpyrrolidone and crosslinked carboxymethylcellulose sodium. The said lubricants can be the lubricants that are conventionally used in this preparation field, preferably one or more among colloidal silica, sodium stearyl fumarate, talcum powder and magnesium stearate. The said suspending agents can be the suspending agents that are conventionally used in this field, preferably one or more among xanthan gum, arabic gum, povidone, tragacanth, sodium alginate, glycerin, sucrose, mannitol, sorbitol, methyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl starch sodium, carboxymethyl cellulose sodium and silicon bentonite. The dosage of the said excipients can be selected according to the conventional knowledge in the present field, the dosage of the said fillers and the water-soluble carriers aforementioned is preferably 70˜90% the mass of aripiprazole medicament formulation, which is to say that if the water-soluble carriers are not added before the alkalizer is added, the dosage of the said fillers are 70˜90% the mass of aripiprazole medicament formulation, while lithe water-soluble carriers are added, the dosage of the said water-soluble carriers and the said fillers should just satisfy that the sum of the dosage of the said water-soluble carriers and the said fillers is 70˜90%. The total dosage of the said disintegrants is preferably 1˜10% the mass of aripiprazole medicament formulation, and the total dosage of the said disintegrants here refers to the dosage of the disintegrants used as excipients of wet granulation and the dosage of the disintegrants that are added before the alkalizer. The dosage of the said lubricant is preferably 0.2˜3% the mass of aripiprazole medicament formulation. The dosage of the said suspending agents is preferably 85˜95% the mass of the dry suspension.
[0029] In a preferred embodiment of the present invention, when the solid particles preparations, tablets or capsules of aripiprazole are prepared by wet granulation, the method comprises the following steps: (1) dissolving aripiprazole in aqueous ethanol solution having hydrochloric acid to obtain the medicament having acidic solution; (2) adding water-soluble carrier, antioxidant and alkalizer to get a mixture, and the water-soluble carriers and antioxidants being added before or during the time when the alkalizers are added; (3) caning on wet granulation with the said mixture and the said excipients to obtain the solid particles preparations, or earring on wet granulation and pressing to obtain tablets, or caning on wet granulation and loading capsules to obtain capsules; wherein the alkalizers are sodium hydroxide and/or sodium carbonate; when the said alkalizer is sodium hydroxide, the said alkalizer is added in the form of water solution of sodium hydroxide, the molar ratio of hydrochloric acid to aripiprazole is 0.95˜1.1, preferably 1.0˜1.05; the molar ratio of alkalizer to hydrochloric acid is 0.99˜1.02.
[0030] In step (1), the said medicament having acidic solution also contains a surfactant and/or a solubilizer, and the said surfactant and/or solubilizer is preferably one or more among povidone, sodium dodecyl sulfate, poloxamers, Tween 80 and polyoxyethylenated castor oil. The dosage of the said surfactant and/or solubilizer is preferably 0.02˜1 times the mass of aripiprazole. The concentration of ethanol in the said medicament having acidic solution is preferably 70 wt % or more, more preferably 80 wt % or more. The said medicament having acidic solution also contains a water-soluble carrier: polyethylene glycol 6000 and hydroxypropyl-β-cyclodextrin.
[0031] In step (2), the said mixture also contains a disintegrant, the said disintegrant is added before or during the time when the alkalizer is added. The said disintegrant is preferably sodium carboxymethyl starch and/or cross-linked polyvinylpyrrolidone. The dosage of the said disintegrant is preferably 0.6˜0.72 times the mass of aripiprazole. The said water-soluble carrier is preferably one or more among lactose, mannitol, polyethylene glycol 6000 and hydroxypropyl-β-cyclodextrin. The dosage of the said water-soluble carrier is preferably 2˜6 times the mass of aripiprazole. The said antioxidant is preferably one or more among sodium bisulfite, sodium sulfite, sodium ascorbate, L-cysteine and sodium thiosulfate. The dosage of the said antioxidant is preferably 1˜10% the mass of aripiprazole, more preferably 1˜5%. The concentration of the water solution of sodium hydroxide is preferably 10˜20 wt %. There is no particular requirement to the order of addition of the said disintegrant, antioxidant and water-soluble carrier. When the alkalizer is sodium hydroxide, it is preferably to add one or more among citric acid, glycine and malic acid before or during the time when the alkalizer is added, and the dosage of which is preferably 0.5˜2% the mass of aripiprazole.
[0032] In step (3), the said filler is preferably one or more among lactose, microcrystalline cellulose, starch and mannitol, and the total dosage of the said filler and the said water-soluble carrier is 80˜90% the mass of the solid particles preparations, tablets or capsules of aripiprazole. The said disintegrant is preferably one or more among sodium carboxymethyl starch, hydroxypropyl cellulose, cross-linked polyvinylpyrrolidone and crosslinked carboxymethylcellulose sodium, whose dosage is preferably 1˜10% the mass of tablets or capsules of aripiprazole. The said lubricant is preferably one or more among colloidal silica, sodium stearyl fumarate, talcum powder and magnesium stearate, whose dosage is preferably 0.5˜3% the mass of tablets or capsules of aripiprazole.
[0033] In a preferred embodiment of the present invention, when the dry suspension of aripiprazole is prepared by wet granulation, the method comprises the following steps: (1) dissolving aripiprazole in an aqueous ethanol solution having hydrochloric acid to obtain the medicament having acidic solution; (2) adding a water-soluble carrier, antioxidant and alkalizer to obtain a mixture, and the water-soluble carrier and antioxidant being added before or during the time when the alkalizer is added; (3) earring on wet granulation with the said mixture and the said excipients to obtain the dry suspension of aripiprazole; wherein the alkalizer is sodium hydroxide and/or sodium carbonate. When the said alkalizer is sodium hydroxide, it is added in the form of aqueous sodium hydroxide solution. The molar ratio of hydrochloric acid to aripiprazole is 0.95˜1.1, preferably 1.0˜1.05. The molar ratio of alkalizer to hydrochloric acid is 0.99˜1.02.
[0034] Wherein step (1) and step (2) are as mentioned above, and in step (3), the said suspending agent is preferably one or more among xanthan gum, mannitol and hydroxypropyl methyl cellulose. The dosage of the said suspending agent is preferably 90˜96% the mass of the dry suspension. The dosage of the said lubricant is preferably 0.2˜0.5% the mass of the dry suspension.
[0035] In the present invention, the excipients can be selected according to the prior art when a suspension is prepared, and the said excipients include 5˜25% suspending agent, 0˜0.5% wetting agent, 0˜0.3% preservative, 0˜3% corrective agent and solvent, the percentage is mass percentage relative to the suspension. The said suspending agent is preferably selected from one or more among xanthan gum, arabic gum, povidone, tragacanth, sodium alginate, glycerin, sucrose, mannitol, sorbitol, methyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl starch sodium, carboxymethyl cellulose sodium and silicon bentonite. The said wetting agent is preferably selected from one or more among Tween 80, polyoxyethylene aliphatic alcohol ether (Brij), polyoxyethylene fatty acid (Myrij), poloxamer and sodium dodecyl sulfate. The said solvent is usually water or the mixture of water and alcohol. The said alcohol is generally one or more among propylene glycol, benzyl alcohol and ethanol. The dosage of the solvent is to complement the weight percent of the suspension up to 100%. The said suspension also includes preservative and/or corrective agent, and the preservative is preferably selected from one or more among benzoic acid, sodium benzoate, propyl hydroxybenzoate, sodium propyl hydroxybenzoate, methyl hydroxybenzoate and sodium methyl hydroxybenzoate, sorbic acid and so on, the corrective agent is preferably selected from one or more among aspartame, stevia, flavor and so on.
[0036] In the present invention, the method of preparing the said suspension is mixing the said medicament having acidic solution with the alkalizer, and preferably is carried out concretely according to any one of the following methods: method (1) uniformly mixing the medicament having acidic solution with the alkalizer or the alkalizer-containing solution, and then mixing them with the suspending agent solution; method (2) uniformly mixing the medicament having acidic solution with the water-soluble carrier and/or disintegrant, and then uniformly mixing them with the alkalizer or the alkalizer-containing solution, further mixing them with the suspending agent solution; method (3) uniformly mixing the medicament having acidic solution with the water-soluble carrier and/or disintegrant, and also with the suspending agent solution, and then mixing them with the alkalizer or the alkalizer-containing solution. Wherein the said suspending agent solution is obtained by mixing the other excipients contained in the said suspending agent with the suspending agent. In the process of preparation, the conventional steps for preparing a suspension can also be used in the present field, such as proceeding the dispersing treatment with a colloid mill, homogenizer and so on.
[0037] In a preferred embodiment of the present invention, the method of preparing a suspension comprises the following steps: (1) dissolving aripiprazole in a solution having an acidifier so as to obtain a medicament having acidic solution; (2) adding the said water-soluble carrier, the said antioxidant and the said alkalizer to obtain a mixture, and the water-soluble carrier and antioxidant being added before or during the time when the alkalizer is added; (3) mixing the mixture with the said suspending agent solution. Wherein, the said alkalizer is sodium hydroxide, and the said sodium hydroxide is added in the form of aqueous sodium hydroxide solution with a concentration of 5˜20 wt %. The said acidifier is hydrochloric acid and/or lactic acid, and the molar ratio of the hydrochloric acid to aripiprazole is preferably 1.0˜1.1, the molar ratio of the said lactic acid to aripiprazole is generally 1.8˜2.5, preferably 2˜2.1. The molar ratio of the alkalizer to hydrochloric acid is 0.99˜1.02. In step (1), the solvent of the medicament having acidic solution is one or more among the following alcohols, or the aqueous solution of the following alcohols: ethanol, propylene glycol, glycerol and benzyl alcohol.
[0038] Wherein step (1), the said medicament having acidic solution preferably contains a surfactant and/or a solubilizer. The said surfactant and/or solubilizer is preferably one or more among povidone, Tween 80 and poloxamer. The dosage of the said surfactant and/or solubilizer is preferably 0.25˜2.5 times the mass of aripiprazole. The concentration of alcohol in the said aqueous alcohol solution is preferably 70 wt % or more. The said medicament having acidic solution also preferably contains a water-soluble carrier: polyethylene glycol 6000. In step (2), the said water-soluble carrier is preferably one or more among sucrose, mannitol and polyethylene glycol 6000. The total dosage of the said water-soluble carrier is preferably 7˜10 times the mass of aripiprazole. The said antioxidant is preferably one or more among sodium bisulfite, sodium sulfite, sodium ascorbate, L-cysteine and sodium thiosulfate. The dosage of the said antioxidant is preferably 10˜100% the mass of aripiprazole. In step (3), the said suspending agent is preferably one or more among xanthan gum, hydroxypropyl methyl cellulose, sucrose and sodium carboxymethyl cellulose. The dosage of the said suspending agent is preferably 1˜15.5% the mass of the suspension.
[0039] In the preparation method of the present invention, the particle size of aripiprazole formulation can be controlled by adjusting the ratio in prescription and the conditions of operation. The said ratio in prescription refers to the ratio of solvents used for preparing the medicament having acidic solution particularly, and as well as the species and ratios of water-soluble carriers and other reagents of the solid dispersion added in the medicament having acidic solution before the alkalizer is added. The particle size of aripiprazole can also be affected by the stirring speed, the method of adding an alkalizer and so on. Therefore, the preparation method disclosed in the invention can adjust the particle size of aripiprazole according to the requirement, which has also provided an effective method of ensuring and controlling the dissolution characteristic of preparation. In the present invention, when the solvent is aqueous ethanol solution, the particle size would be affected by the concentration of the solvent, and the size will be the smallest when the concentration reaches 95%. The regular between the particle size of aripiprazole and the stirring speed is as follows: with the increase of the stirring speed, the particle size is presented an increasing tendency. When one of the surfactant, solubilizer and water-soluble carrier is added into the medicament having acidic solution, the particle size will be reduced with the increasing of the dosage of said excipients. When at least two of the surfactant, solubilizer and water-soluble carrier are added into the medicament having acidic solution and under the condition that the dosage of one excipient is fixed, the particle size will be reduced with the increase of the dosage of the other excipient. When aripiprazole:lactose is 1:6 and aripiprazole: Tween 80 (or poloxamer or sodium dodecyl sulfate) is 1:0.2, the effect of reducing the particle size realized by adding Tween-80 is better than poloxamer, and poloxamer is better than sodium dodecyl sulfate. When one of mannitol, lactose, maltitol and sucrose is added into the medicament having acidic solution, the particle size will be reduced with the increase of the dosage of the said excipient.
[0040] Further, the present invention has also provided an aripiprazole medicament formulation produced by the above-mentioned method.
[0041] In the present invention, the mentioned optimized conditions can be optionally combined based on the general knowledge in this field to obtain preferred embodiments.
[0042] In the present invention, the used reagents and materials can be commercially available.
[0043] The positive effects of the present invention are:
[0044] (1) The amount of related substances is significantly decreased in the aripiprazole medicament formulation obtained by the preparation method in this invention, and the formulation also possesses great solubility and stability, high bioavailability, small individual differences. (2) The insoluble aripiprazole is highly dispersed in suitable excipients during the preparation of the invention, which has changed the surface properties of microcrystalline, improved the wettability and content uniformity of the insoluble drug. (3) The preparation method of the invention combines the microcrystalline of the insoluble medicament and the process of dispersion with the granulation, which realizes simple operation, low cost, no special equipment requirement and easy application to industrialization. (4) The preparation method of the invention eliminates the influence of the form of crude drug on quality of preparation, and avoids the defects of serious pollution, great lost and high security risks caused by the pretreatment of aripiprazole.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0045] Then the present invention is further illustrated by the following embodiments, but is not limited by the following embodiments. In the following embodiments, the experimental methods without specific conditions, can be carried on by conventional conditions or the conditions recommended by manufacturers.
[0046] In the following embodiments, dosage specification counts as the dosage of aripiprazole, for example, 5 mg/tablet refers to 5 mg aripiprazole per tablet. Dosage unit is gram, and percentage refers to mass percentage. The stirring linear speed without specified when water-soluble carrier and alkalizer are added in the medicament having acidic solution is 160 m/min.
[0047] In the embodiments, the solvent of medicament having acidic solution is the solvent contained in the prepared medicament having acidic solution, and the solvent refers to all of the solvents added during the preparation of a medicament preparation. Take example 1 for example, the preparation of the medicament having acidic solution is: mixing povidone, 15.2 g anhydrous ethanol, 4.3 g 10% aqueous hydrochloric acid solution and 5 g aripiprazole to prepare the medicament having acidic solution. The solvent of medicament having acidic solution is aqueous ethanol solution. The mass of the aqueous ethanol solution is: 15.2 g anhydrous ethanol+3.87 g water (4.3−4.3*10%)=19.1 g. The concentration of the aqueous ethanol solution is: (15.2/19.1)*100%=80%. The mass of the solvent is: 19.2 g the solvent of medicament having acidic solution plus the water contained in aqueous sodium hydroxide solution (2.36−2.36*20%)=19.2+1.888=21.0 g, and the concentration of the solvent is (15.2/21)*100%=72%.
[0048] Hereinafter, [1] refers to the percentage of aripiprazole counting for the mass of dry material of wet granulation. [2] refers to the percentage of the solvent counting for the mass of dry material of wet granulation. [3] refers to the percentage of aripiprazole counting for the mass of the suspension.
Comparison Examples 1˜2 and Examples 1˜2
Prescription and Preparation Method of Aripiprazole Granules (Unit: Gram)
[0049]
[0000]
Comparison Example 1
Comparison Example 2
Example 1
Example 2
Drug
Aripiprazole 5 g
Aripiprazole 5 g
Aripiprazole 5 g
Aripiprazole 5 g
(2.4% [1] , grain
(2.4% [1] , grain
(2.4% [1] , without
(2.4% [1] , without
diameter D [4, 3]
diameter D [4, 3]
pretreatment)
pretreatment)
92.7 micron)
26.3 micron)
Excipient
Lactose 200 g,
Lactose 200 g,
Lactose 200 g,
Lactose 172.5 g,
Povidone
Povidone
Povidone
Mannitol 25 g,
K-30 2.5 g
K-30 2.5 g
K-30 2.5 g,
Povidone K-30 5 g,
Sodium Hydrogen
Sodium Hydrogen
Sulfite 0.1 g
Sulfite 0.1 g
Medicament
—
—
80% Aqueous
91% Aqueous
having
ethanol solution
ethanol solution
acidic
19.1 g
19.0 g
solution
Solvent
75% Aqueous
75% Aqueous
72% Aqueous
83% Aqueous
ethanol solution
ethanol solution
ethanol solution
ethanol solution
20 g (9.6% [2] )
20 g (9.6% [2] )
21.0 g (10.1% [2] )
20.9 g (10.0% [2] )
Acidifier
—
—
10% Aqueous hydrochloric acid
36% Hydrochloric acid
solution 4.3 g (molar ratio of
1.18 g (molar ratio of
it to aripiprazole is 1.05)
it to aripiprazole is 1.05)
Alkalizer
—
—
20% Aqueous Sodium hydroxide
20% Aqueous sodium hydroxide
solution 2.36 g (molar ratio of
solution 2.33 g (molar ratio of
it to hydrochloric acid is 1.0)
it to hydrochloric acid is 1.0)
Preparation
Grind aripiprazole
Carry on micron-
Mix povidone, 15.2 g
Mix povidone, 18.24 g
Technology
by a universal
ization treatment
anhydrous ethanol, aqueous
95% ethanol, hydrochloric acid
pulverizer and
with aripiprazole,
hydrochloric acid solution
and aripiprazole to prepare
then make it pass
uniformly mix it
and aripiprazole to prepare
medicament having acidic
through 100 mesh
with lactose;
medicament having acidic
solution, add sodium hydrogen
sieve; uniformly
povidone in 75%
solution; add sodium hydrogen
sulfite; add mannitol when
mix it with lactose;
aqueous ethanol
sulfite; add 15% amount of
stirring; then add aqueous
povidone in 75%
solution is added,
lactose when stirring; then
sodium hydroxide solution
aqueous ethanol
stir and granulation;
add aqueous sodium hydroxide
dropwise when stirring. Add
solution is added,
finish granule after
solution quickly when stirring.
the above mixture into the
stir and granulation;
drying wet granules.
Add the above mixture into the
lactose to carry out stirring
finish granule after
rest lactose to carry out stirring
granulation; finish granule after
drying wet granules.
granulation; finish granule after
drying wet granules.
drying wet granules.
Contrastive Examples 3˜4 and Examples 3˜4
Prescription and Preparation Method of Aripiprazole Tablets (Unit: Gram)
[0050]
[0000]
Contrastive Example 3
Contrastive Example 4
Example 3
Example 4
Drug
Aripiprazole 5 g
Aripiprazole 5 g
Aripiprazole 5 g
Aripiprazole 5 g
(4.2% [1] , grain
(4.2% [1] , grain
(4.2% [1] , without
(4.2% [1] , without
diameter D[4, 3]
diameter D[4, 3]
pretreatment)
pretreatment)
92 micron)
25 micron)
Excipient
Lactose 75 g,
Lactose 75 g,
Lactose 75 g,
Mannitol 72.5 g,
Povidone K-30 2.5 g,
Povidone K-30 2.5 g,
Povidone K-30 2.5 g,
Povidone K-30 5 g,
Microcrystalline
Microcrystalline
Microcrystalline
Microcrystalline
Cellulose 30 g,
Cellulose 30 g,
Cellulose 30 g,
Cellulose 30 g,
Carboxymethyl Starch
Carboxymethyl Starch
Sodium Hydrogen Sulfite
Sodium Hydrogen Sulfite
Sodium 5 g, Magnesium
Sodium 5 g, Magnesium
0.1 g, Carboxymethyl
0.1 g, Carboxymethyl
Stearate 0.9 g
Stearate 0.9 g
Starch Sodium 5 g,
Starch Sodium 5 g,
Magnesium Stearate 0.9 g
Magnesium Stearate 0.9 g
Medicament
—
—
80% Aqueous
91% Aqueous
having
ethanol solution
ethanol solution
acidic
19.1 g
19.0 g
solution
Solvent
75% Aqueous
75% Aqueous
65% Aqueous
75% Aqueous
ethanol solution
ethanol solution
ethanol solution
ethanol solution
20 g (16.9% [2] )
20 g (16.9% [2] )
23.3 g (19.5% [2] )
23.2 g (19.5% [2] )
Acidifier
—
—
10% Aqueous hydrochloric
36% Hydrochloric
acid solution 4.3 g
acid 1.18 g
(molar ratio of it to
(molar ratio of it to
aripiprazole is 1.05)
aripiprazole is 1.05)
Alkalizer
—
—
10% Aqueous sodium
10% Aqueous sodium
hydroxide solution
hydroxide solution
4.7 g (molar ratio of
4.7 g (molar ratio of
it to hydrochloric acid
it to hydrochloric acid
is 1.0)
is 1.0)
Preparation
Mix aripiprazole with
Mix aripiprazole with
Mix povidone, 15.2 g anhydrous
Mix povidone, 18.24 g 95% ethanol,
Technology
lactose, microcrystalline
lactose, microcrystalline
ethanol, aqueous hydrochloric acid and
hydrochloric acid and aripiprazole to
cellulose uniformly;
cellulose uniformly;
aripiprazole to prepare medicament
prepare medicament having acidic
add povidone, aqueous
add povidone, aqueous
having acidic solution; add sodium
solution; add sodium hydrogen sulfite;
ethanol solution to
ethanol solution to
hydrogen sulfite; add 40% amount of
add 35% amount of mannitol when
carry out stirring granu-
carry out stirring granu-
lactose when stirring, then add aqueous
stirring; then add aqueous sodium
lation; finish granule
lation; finish granule
sodium hydroxide solution quickly
hydroxide solution dropwise when
after drying wet granules;
after drying wet granules;
when stirring to get mixture. Add the
stirring to get mixture. Add the mixture
add magnesium stearate
add magnesium stearate
mixture to the mixed powder of the rest
to the mixed powder of the rest
and carboxymethyl starch
and carboxymethyl starch
lactose and microcrystalline cellulose to
mannitol and microcrystalline cellulose
sodium, uniformly mix
sodium, uniformly mix
carry out stirring granulation; finish
to carry out stirring granulation; finish
and press.
and press.
granule after drying wet granules. Add
granule after drying wet granules. Add
magnesium stearate and carboxymethyl
magnesium stearate and carboxymethyl
starch sodium, uniformly mix and press.
starch sodium, uniformly mix and
press.
Examples 5 and 6
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0051]
[0000]
Example 5
Example 6
Drug
Aripiprazole 5 g (4.1% [1] , without
Aripiprazole 5 g (4.1% [1] , without
pretreatment)
pretreatment)
Excipient
Lactose 70 g, Microcrystalline
Lactose 70 g, Microcrystalline
Cellulose 20 g, Starch 20 g,
Cellulose 20 g, Starch 20 g,
Povidone K-30 2.5 g, Sodium
PovidoneK-30 2.5 g, Sodium
Hydrogen Sulfite 0.5 g,
Hydrogen Sulfite 0.5 g,
Magnesium Stearate 0.7 g, Cross-
Magnesium Stearate 0.7 g, Cross-
linked polyvinylpyrrolidone 2 g
linked polyvinylpyrrolidone 2 g
Medicament
96% Aqueous ethanol solution 15.7 g
77% Aqueous ethanol solution 15.6 g
having
acidic
solution
Solvent
76% Aqueous ethanol solution 19.7 g (16.2% [2] )
61% Aqueous ethanol solution 19.5 g (16.1% [2] )
Acidifier
36% Hydrochloric acid 1.1 g
10% Aqueous hydrochloric acid solution 3.96 g
(molar ratio of it to aripiprazole is 0.98)
(molar ratio of it to aripiprazole is 0.98)
Alkalizer
10% Aqueous sodium hydroxide solution 4.4 g
10% Aqueous sodium hydroxide solution 4.4 g
(molar ratio of it to hydrochloric acid is 1.01)
(molar ratio of it to hydrochloric acid is 1.01)
Preparation
Mix povidone, 15 g anhydrous ethanol, hydrochloric
Mix povidone, 12 g anhydrous ethanol, aqueous hydrochloric
Technology
acid and aripiprazole to prepare medicament having
acid solution and aripiprazole to prepare medicament having
acidic solution; add 20% amount of lactose when
acidic solution; add 20% amount of lactose when stirring; then
stirring; then add sodium hydrogen sulfite and aqueous
add sodium hydrogen sulfite and aqueous sodium hydroxide
sodium hydroxide solution when stirring to get mixture.
solution when stirring to get mixture. Add the mixture into
Add the mixture into the mixed powder of the rest 80%
the mixed powder of the rest 80% amount of lactose, starch
amount of lactose, starch and microcrystalline cellu-
and microcrystalline cellulose to carry out stirring granulation;
lose to carry out stirring granulation; finish granule
finish granule after drying wet granules; add magnesium stearate
after drying wet granules; add magnesium stearate and
and cross-linked polyvinylpyrrolidone, uniformly mix and press.
cross-linked polyvinyl-pyrrolidone, uniformly mix and
press.
Examples 7 and 8
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0052]
[0000]
Example 7
Example 8
Drug
Aripiprazole 5 g (4.2% [1] , without
Aripiprazole 5 g (4.1% [1] , without
pretreatment)
pretreatment)
Excipient
Lactose 60 g, Microcrystalline Cellulose 20 g,
Lactose 75 g, Microcrystalline Cellulose 30 g,
Starch 25 g, Poloxamer188 0.5 g, Carboxymethyl
Povidone K-30 2.5 g,, Carboxymethyl Starch Sodium
Starch Sodium 6 g, L-cysteine 0.1 g, Magnesium
6 g, Sodium Hydrogen Sulfite 0.1 g, Magnesium
Stearate 0.8 g
Stearate 0.8 g
Medicament
73% Aqueous ethanol solution 15.6 g
76% Aqueous ethanol solution 15.7 g
having
acidic
solution
Solvent
58% Aqueous ethanol solution 19.6 g (16.5% [2] )
61% Aqueous ethanol solution (16.1% [2] )
Acidifier
10% Hydrochloric acid 4 g (molar
10% Aqueous hydrochloric acid solution 3.4 g
ratio of it to aripiprazole is 0.99)
(molar ratio of it to aripiprazole is 0.84)
Citric Acid Monohydrate 0.35 g (molar ratio of
it to aripiprazole is 0.15)
Alkalizer
10% Aqueous Sodium hydroxide solution 4.4 g
10% Aqueous Sodium hydroxide solution 4.35 g
(molar ratio of it to hydrochloric acid is 1.0)
(molar ratio of it to the mixed acid is 0.99)
Preparation
Mix 12 g 95% ethanol, aqueous hydrochloric acid
Mix 12.6 g 95% ethanol, aqueous hydrochloric acid
Technology
solution, poloxamer and aripiprazole to prepare
solution, citric acid monohydrate and aripiprazole
medicament having acidic solution; add L-cysteine,
to prepare medicament having acidic solution; add
50% amount of carboxymethyl starch sodium and 40%
sodium hydrogen sulfite and 30% amount of lactose
amount of lactose when stirring; add aqueous sodium
when stirring, then add aqueous sodium hydroxide
hydroxide solution when stirring to get mixture.
solution when stirring to get mixture. Add the mixture
Add the mixture into the mixed powder of 60% amount
to the mixed powder of 70% amount of lactose, 50%
of lactose, starch and microcrystalline cellulose
amount of carboxymethyl starch sodium and microcrys-
to carry out stirring granulation; finish granule
talline cellulose to carry out stirring granulation;
after drying wet granules; add magnesium stearate
finish granule after drying wet granules; add magnesium
and 50% amount of carboxymethyl starch sodium,
stearate and 50% amount of carboxymethyl starch sodium,
uniformly mix and press.
uniformly mix and press.
Examples 9 and 10
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Grain)
[0053]
[0000]
Example 9
Example 10
Drug
Aripiprazole 5 g (4.5% [1] , without
Aripiprazole 5 g (4.5% [1] , without
pretreatment)
pretreatment)
Excipient
Lactose 70 g, Microcrystalline Cellulose 30 g,
Lactose 70 g, Microcrystalline Cellulose 30 g,
Povidone K-30 1.5 g, Sodium Sulfite 0.05 g, Citric
Povidone K-30 1.5 g, Sodium Sulfite 0.05 g, Citric
Acid Monohydrate 0.05 g, Sodium Dodecyl Sulfate
Acid Monohydrate 0.05 g, Sodium Dodecyl Sulfate
0.1 g, Carboxymethyl Starch Sodium 4 g, Magnesium
0.1 g, Carboxymethyl Starch Sodium 4 g, Magnesium
Stearate 0.6 g
Stearate 0.6 g
Medicament
76% Aqueous ethanol solution 18.7 g
76% Aqueous ethanol solution 18.7 g
having
acidic
solution
Solvent
63% Aqueous ethanol solution 22.7 g (20.3% [2] )
63% Aqueous ethanol solution 22.7 g (20.3% [2] )
Acidifier
10% Hydrochloric acid 4.1 g
10% Aqueous hydrochloric acid solution 4.1 g
(molar ratio of it to aripiprazole is 1.01)
(molar ratio of it to aripiprazole is 1.01)
Alkalizer
10% Aqueous Sodium hydroxide solution 4.5 g
10% Aqueous sodium hydroxide solution 4.5 g
(molar ratio of it to hydrochloric acid is 1.0)
(molar ratio of it to hydrochloric acid is 1.0)
Preparation
Mix 15 g 95% ethanol, sodium dodecyl sulfate,
Mix 15 g 95% ethanol, sodium dodecyl sulfate,
Technology
povidone, aqueous hydrochloric acid solution and
povidone, aqueous hydrochloric acid solution and
aripiprazole to prepare medicament having acidic
aripiprazole to prepare medicament having acidic
solution; add sodium sulfite, citric acid mono-
solution; add sodium sulfite, citric acid mono-
hydrate and 20% amount of lactose when stirring;
hydrate and 50% amount of lactose when stirring;
then add aqueous sodium hydroxide solution when
then add aqueous sodium hydroxide solution when
stirring to get mixture. Add the mixture to the
stirring to get mixture. Add the mixture into the
mixed powder of 80% amount of lactose and micro-
mixed powder of 50% amount of lactose and micro-
crystalline cellulose to carry out stirring granula-
crystalline cellulose to carry out stirring granula-
tion; finish granule after drying wet granules; add
tion; finish granule after drying wet granules; add
magnesium stearate and carboxymethyl starch sodium,
magnesium stearate and carboxymethyl starch sodium,
uniformly mix and press.
uniformly mix and press.
Examples 11
Prescription and Preparation Method of Aripiprazole Tablets (10 Mg/Tablet) (Unit: Gram)
[0054]
[0000]
Drug
Aripiprazole 10 g (7.8% [1] , without pretreatment)
Excipient
Lactose 70 g, Povidone K-30 5 g, Starch 37 g, Tween-80
0.1 g, Sodium Hydrogen Sulfite 0.5 g, DL Malic Acid
0.1 g, Carboxymethyl Starch Sodium 3, Colloidal Silica
0.2 g, Sodium Stearyl Fumarate 0.8 g
Medicament
94% Ethanol 26.5 g
having
acidic
solution
Solvent
83% Aqueous ethanol solution 30.1 g (23.4% [2] )
Acidifier
36% Hydrochloric acid 2.3 g (molar ratio of it to
aripiprazole is 1.02)
Alkalizer
20% Aqueous sodium hydroxide solution 4.5 g
(molar ratio of it to hydrochloric acid is 0.99)
Preparation
Mix 25 g anhydrous ethanol, Tween-80, povidone,
Technology
hydrochloric acid and aripiprazole to prepare medica-
ment having acidic solution; stir when adding malic acid,
sodium hydrogen sulfite and 40% amount of lactose; then
add aqueous sodium hydroxide solution when stirring
to get mixture. Add the mixture to the mixed powder
of 60% amount of lactose and starch to carry out
stirring granulation; finish granule after drying wet
granules; add colloidal silica, carboxymethyl starch
sodium, sodium stearyl fumarate, uniformly mix and
press.
Examples 12
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0055]
[0000]
Drug
Aripiprazole 5 g (4.1% [1] , without pretreatment)
Excipient
Lactose 60 g, Microcrystalline Cellulose 40 g, Polyethylene
Glycol 6000 10 g, Polyoxyethylated Castor Oil 0.1 g,
Carboxymethyl Starch Sodium 6 g, Sodium Sulfite 0.2 g,
Citric Acid Monohydrate 0.06 g, Magnesium Stearate 0.8 g
Medicament
72% Aqueous ethanol solution 15.68 g
having
acidic
solution
Solvent
58% Aqueous ethanol solution 19.8 g (16.1% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 4.2 g
(molar ratio of it to aripiprazole is 1.03)
Alkalizer
10% Aqueous Sodium hydroxide solution 4.5 g
(molar ratio of it to hydrochloric acid is 0.98)
Preparation
Mix 12 g 95% ethanol, polyethylene glycol, polyoxyethyl-
Technology
ated castor oil, aqueous hydrochloric acid solution and
aripiprazole to prepare medicament having acidic solu-
tion; add sodium sulfite, citric acid monohydrate, 60%
amount of carboxymethyl starch sodium and 50% amount
of lactose when stirring; then add aqueous sodium hydrox-
ide solution when stirring to get mixture. Add the mix-
ture to the mixed powder of 50% amount of lactose and
microcrystalline cellulose to carry out stirring granula-
tion; finish granule after drying wet granules; add 40%
amount of carboxymethyl starch sodium and magnesium
stearate, uniformly mix and press.
Examples 13
Prescription and Preparation Method of Aripiprazole Tablets (10 Mg/Tablet) (Unit: Gram)
[0056]
[0000]
Drug
Aripiprazole 10 g (6.8% [1] , without pretreatment)
Excipient
Lactose 65 g, Microcrystalline Cellulose 65 g, Povidone
K-30 2 g, Sodium Hydrogen Sulfite 0.2 g, Citric Acid
Monohydrate 0.06 g, Carboxymethyl Starch Sodium 3 g,
Magnesium Stearate 0.8 g
Medicament
96% Aqueous ethanol solution 31.41 g
having
acidic
solution
Solvent
76% Aqueous ethanol solution 39.2 g (26.5% [2] )
Acidifier
36% Hydrochloric acid 2.2 g (molar ratio of it to
aripiprazole is 0.98)
Alkalizer
10% Aqueous Sodium hydroxide solution 8.6 g
(molar ratio of it to hydrochloric acid is 0.99)
Preparation
Mix 30 g anhydrous ethanol, povidone, hydrochloric acid
Technology
and aripiprazole to prepare medicament having acidic
solution; add citric acid monohydrate, sodium hydrogen
sulfite and aqueous sodium hydroxide solution when
stirring; add 35% amount of lactose when stirring to
get mixture. Add the mixture to the mixed powder of
65% amount of lactose and microcrystalline cellulose
to carry out stirring granulation; finish granule after
drying wet granules; add carboxymethyl starch sodium
and magnesium stearate, uniformly mix and press.
Example 14
Prescription and Preparation Method of Aripiprazole Capsules (10 Mg/Tablet)
[0057] Make the granules (including the carboxymethyl starch sodium and magnesium stearate) before pressing prepared by Example 13 pass through 30 mesh sieve and mix uniformly, then load into capsules.
Examples 15
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0058]
[0000]
Drug
Aripiprazole 5 g (4.1% [1] , without pretreatment)
Excipient
Mannitol 60 g, Microcrystalline Cellulose 40 g, Tween
80 0.2 g, Polyethylene Glycol 6000 10 g, Carboxymethyl
Starch Sodium 6 g, L-cysteine 0.2 g, Magnesium Stearate
0.8 g
Medicament
71% Aqueous ethanol solution 16.1 g
having
acidic
solution
Solvent
58% Aqueous ethanol solution 19.7 g (15.9% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 4.5 g
(molar ratio of it to aripiprazole is 1.11)
Alkalizer
10% Aqueous Sodium hydroxide solution 4 g
(molar ratio of it to hydrochloric acid is 0.81)
Sodium carbonate 0.25 g (molar ratio of it to hydro-
chloric acid is 0.19)
Preparation
Mix 12 g 95% ethanol, polyethylene glycol, Tween 80,
Technology
aqueous hydrochloric acid solution and aripiprazole
to prepare medicament having acidic solution; add
L-cysteine, 60% amount of carboxymethyl starch sodium
and 40% amount of mannitol when stirring; add aqueous
sodium hydroxide solution and the mixed powder of
sodium carbonate and 10% amount of mannitol when
stirring to get mixture. Add the mixture to the mixed
powder of 50% amount of mannitol and microcrystalline
cellulose to carry out stirring granulation; finish
granule after drying wet granules; add 40% amount of
carboxymethyl starch sodium and magnesium stearate,
uniformly mix and press.
Example 16
Prescription and Preparation Method of Aripiprazole Tablets (20 Mg/Tablet) (Unit: Gram)
[0059]
[0000]
Drug
Aripiprazole 20 g (15.0% [1] , without pretreatment)
Excipient
Lactose 60 g, Microcrystalline Cellulose 40 g, Carboxy-
methyl Starch Sodium 6 g, Sodium Sulfite 0.2 g, Povidone
K-30 3 g, Magnesium Stearate 0.8 g, Colloidal Silica 0.3 g
Medicament
78% Aqueous ethanol solution 73.1 g
having
acidic
solution
Solvent
57% Aqueous ethanol solution 100.2 g (74.7% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 14.6 g
(molar ratio of it to aripiprazole is 0.90)
Citric Acid Monohydrate 0.54 g
(molar ratio of it to aripiprazole is 0.05)
Alkalizer
10% Aqueous Sodium hydroxide solution 17.9 g
(molar ratio of it to the acidifier is 1.0)
Preparation
Mix 60 g 95% ethanol, aqueous hydrochloric acid solution,
Technology
povidone, citric acid monohydrate and aripiprazole to
prepare medicament having acidic solution; add sodium
sulfite and ⅓ amount of lactose when stirring; add
aqueous sodium hydroxide solution when stirring; then
add 11 g water and stir uniformly to make granulating
liquid. Mix ⅔ amount of lactose, microcrystalline
cellulose and 60% amount of carboxymethyl starch sodium
uniformly and add them into a multi-functional fluidized
spray granulator, spray granulating liquid on the above-
mentioned mixed excipients by a peristaltic pump to
granulation; add magnesium stearate, colloidal silica
and 40% amount of carboxymethyl starch sodium to the
prepared granules, uniformly mix and then press.
Example 17
Aripiprazole Capsules (10 Mg/Tablet) (Unit: Gram)
[0060] Make the granules (including magnesium stearate, colloidal silica and 40% amount of carboxymethyl starch sodium) before pressing prepared by Example 16 pass through 30 mesh sieve and uniformly mix, then load into capsules.
Example 18
Aripiprazole Suspension (1 Mg/Gram)
[0061]
[0000]
Drug
Aripiprazole 2 g (0.1% [3] , without pretreatment)
Excipient
Sucrose 120 g, Sodium Hydrogen Sulfite 2 g, Polyethylene
Glycol 6000 2 g Sodium Benzoate 2 g, Hydroxypropyl
Methyl Cellulose 100 g, Orange Flavor 2 g
Medicament
73% Aqueous ethanol solution 6.5 g, Glycerin 2 g
having
acidic
solution
Solvent
95% Ethanol 5 g, Glycerin 2 g, Water about 1759 g
Acidifier
10% Aqueous hydrochloric acid solution 1.7 g
(molar ratio of it to aripiprazole is 1.05)
Alkalizer
5% Aqueous Sodium hydroxide solution 3.75 g
(molar ratio of it to hydrochloric acid is 1.0)
Preparation
Disperse hydroxypropyl methyl cellulose with 80° C.
Technology
hot water, add water until the mass reaches 1000 g and
stir to dissolve; then add 90% amount of sucrose, sodium
benzoate and orange flavor, stir to dissolve, get the
mixture of hydroxypropyl methyl cellulose.
Mix 5 g 95% ethanol, glycerin, aqueous hydrochloric acid
solution, polyethylene glycol 6000 and aripiprazole to
prepare medicament having acidic solution; add sodium
hydrogen sulfite and 10% amount of sucrose when stirring,
add aqueous sodium hydroxide solution dropwise when
stirring. Add the mixture of hydroxypropyl methyl cellu-
lose when stirring; finally add water until the total mass
reaches 2000 g and uniformly stir.
Example 19
Suspension (0.5 Mg/Gram)
[0062]
[0000]
Drug
Aripiprazole 5 g (0.5% [3] , without pretreatment)
Excipient
Mannitol 30 g, Povidone K30 2 g, Sodium Hydrogen
Sulfite 0.5 g, Poloxamer188 5 g, Xanthan Gum 50 g,
Sodium Propylparaben 2 g, Aspartame10 g, Flavors 2 g
Medicament
80% Aqueous propylene glycol solution 23.8 g
having
acidic
solution
Solvent
Propylene glycol 20 g, Water about 865 g
Acidifier
10% Aqueous hydrochloric acid solution 4.2 g
(molar ratio of it to aripiprazole is 1.04)
Alkalizer
10% Aqueous sodium hydroxide solution 4.6 g
(molar ratio of it to hydrochloric acid is 1.0)
Preparation
Mix xanthan gum, Sodium Propylparaben, aspartame,
Technology
flavors and 500 g water to prepare the mixture of
xanthan gum.
Mix propylene glycol, aqueous hydrochloric acid solu-
tion, poloxamer, Povidone K30 and aripiprazole to
prepare medicament having acidic solution; add mannitol
when stirring, add aqueous sodium hydroxide solution
and sodium hydrogen sulfite dropwise when stirring.
Add the mixture of xanthan gum when stirring; finally
add water until the total mass reaches 1000 g.
Example 20
Aripiprazole Suspension (1 Mg/Gram)
[0063]
[0000]
Drug
Aripiprazole 2 g (0.2% [3] , without pretreatment)
Excipient
Sucrose 156 g, Sodium Hydrogen Sulfite 1 g, Tween 80
1 g, Povidone K30 4 g, Sodium Benzoate 1 g, Hydroxy-
propyl Methyl Cellulose 50 g, Orange Flavor 2 g
Medicament
Propylene glycol 6 g
having
acidic
solution
Solvent
71% Aqueous propylene glycol solution 11.2 g, Water
about 778 g
Acidifier
DL-Lactic acid 0.81 g (molar ratio of it to aripiprazole is
2.0)
Alkalizer
10% Aqueous sodium hydroxide solution 3.56 g
(molar ratio of it to lactic acid is 1.0)
Preparation
Disperse hydroxypropyl methyl cellulose with 80° C.
Technology
hot water, add water until the mass reaches 500 g and
stir to dissolve; then add 95% amount of sucrose, sodium
benzoate and orange flavor, stir to dissolve, to get the
mixture of hydroxypropyl methyl cellulose. Mix propylene
glycol, lactic acid, Tween 80, povidone and aripiprazole
to prepare medicament having acidic solution; add sodium
hydrogen sulfite and 5% amount of sucrose when stirring,
add aqueous sodium hydroxide solution dropwise when
stirring, add the mixture of hydroxypropyl methyl cellu-
lose when stirring; finally add water until the total mass
reaches 1000 g.
Example 21
Aripiprazole Dry Suspension (20 Mg/Gram)
[0064]
[0000]
Drug
Aripiprazole 5 g (without pretreatment)
Excipient
Mannitol 50 g, Povidone K-30 2 g, Hydroxypropyl Methyl
Cellulose 100 g, Xanthan Gum 90 g, Tween 80 0.5 g,
Sodium Sulfite 0.1 g, Colloidal Silica 0.5 g
Medicament
96% Aqueous ethanol solution16.6 g
having
acidic
solution
Solvent
77% Ethanol 20.7 g
Acidifier
36% Aqueous hydrochloric acid solution 1 g
(molar ratio of it to aripiprazole is 0.88)
Citric Acid Monohydrate 0.28 g
(molar ratio of it to aripiprazole is 0.12)
Alkalizer
10% Aqueous Sodium hydroxide solution 4.5 g
(molar ratio of it to the acidifier is 1.0)
Preparation
Mix povidone, 16 g anhydrous ethanol, hydrochloric acid,
Technology
citric acid monohydrate, Tween80 and aripiprazole to
prepare medicament having acidic solution; add sodium
sulfite and 40% amount of mannitol when stirring; then
add aqueous sodium hydroxide solution dropwise when
stirring. And then add the mixed powder of 60% amount
of mannitol, hydroxypropyl methyl cellulose and xanthan
gum, disperse and then make it pass through 20 mesh sieve;
finish granule after drying; add colloidal silica and mix
uniformly.
Example 22
Aripiprazole Suspension (2 Mg/Gram)
[0065]
[0000]
Drug
Aripiprazole 2 g (0.2% [3] , without pretreatment)
Excipient
Glycerin 54 g, Sucrose 15 g, Sodium Sulfite 0.5 g, Citric
Acid Monohydrate 0.5 g, Tween 80 0.5 g, Polyethylene
Glycol 6000 20 g, Sodium Benzoate 0.1 g, Sodium
Carboxymethyl Cellulose 10 g
Medicament
79% Aqueous ethanol solution 7.6 g
having
acidic
solution
Solvent
Benzyl alcohol 5 g, Glycerin 6 g, Anhydrous ethanol
6 g, Water about 878 g
Acidifier
10% Aqueous hydrochloric acid solution 1.8 g
(molar ratio of it to aripiprazole is 1.1)
Alkalizer
10% Aqueous Sodium hydroxide solution 2 g
(molar ratio of it to hydrochloric acid is 1.0)
Preparation
Mix sodium carboxymethyl cellulose, benzyl alcohol,
Technology
sodium benzoate, 500 g water and 90% amount of glycerin
to prepare the mixture of sodium carboxymethyl cellulose.
Mix anhydrous ethanol, 10% amount of glycerin, Tween80,
aqueous hydrochloric acid solution and aripiprazole to
prepare medicament having acidic solution; add sodium
hydrogen sulfite, citric acid monohydrate, polyethylene
glycol and sucrose when stirring; add aqueous sodium
hydroxide solution dropwise when stirring. Add the
mixture of sodium carboxymethyl cellulose when stirring;
finally add water until the total mass reaches 1000 g and
uniformly mix.
Examples 23
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0066]
[0000]
Drug
Aripiprazole 5 g (5.0% [1] , without pretreatment)
Excipient
Lactose 20 g, Microcrystalline Cellulose 40 g, Hydroxy-
propyl-β-Cyclodextrins 30 g, Poloxamer188 0.2 g, Sodium
Hydrogen Sulfite 0.05 g, Crosslinked carboxymethyl-
cellulose Sodium 1 g, Talcum Powder 2.5 g, Magnesium
Stearate 0.5 g
Medicament
91% Aqueous ethanol solution 18.7 g
having
acidic
solution
Solvent
91% Aqueous ethanol solution 18.7 g (18.6% [2] )
Acidifier
36% Hydrochloric acid 1.13 g (molar ratio of it to
aripiprazole is 1.0)
Alkalizer
Sodium carbonate 1.06 g (molar ratio of it to hydrochloric
acid is 0.90)
Preparation
Mix 18 g 95% ethanol, poloxamer, hydrochloric acid and
Technology
aripiprazole to prepare medicament having acidic solution;
add sodium hydrogen sulfite, hydroxypropyl β-cyclo-
dextrins and lactose when stirring to get mixture. Add
the mixture into microcrystalline cellulose that is
uniformly mixed with sodium carbonate and stir to get
soft material, carry out extrusion granulation, finish
granule after drying wet granules; add crosslinked
carboxymethylcellulose sodium, talcum powder and
magnesium stearate, mix uniformly and press.
Example 24
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0067]
[0000]
Drug
Aripiprazole 5 g (4.0% [1] , without pretreatment)
Excipient
Lactose 60 g, Microcrystalline Cellulose 35 g, starch 10 g,
Povidone K30 0.1 g, Glycine 0.025 g, Hydroxypropyl
cellulose 12 g, Sodium Thiosulfate 0.05 g, Magnesium
Stearate 0.7 g
Medicament
81% Aqueous ethanol solution 18.6 g
having
acidic
solution
Solvent
64% Aqueous ethanol solution 23.4 g (18.8% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 4.05 g
(molar ratio of it to aripiprazole is 1.0)
Alkalizer
20% Aqueous sodium carbonate solution 5.92 g
(molar ratio of it to hydrochloric acid is 1.01)
Preparation
Mix 15 g anhydrous ethanol, povidone, aqueous hydro-
Technology
chloric acid solution and aripiprazole to prepare medica-
ment having acidic solution; add sodium thiosulfate,
glycine and 40% amount of lactose when stirring;
add aqueous sodium carbonate solution when stirring
to get mixture. Add the mixture into the mixed powder
of 60% amount of lactose, starch and microcrystalline
cellulose and carry out stirring granulation; finish
granule after drying wet granules; add hydroxypropyl
cellulose and magnesium stearate, mix uniformly and
press.
Example 25
Prescription and Preparation Method of Aripiprazole Tablets (10 Mg/Tablet) (Unit: Gram)
[0068]
[0000]
Drug
Aripiprazole 10 g (7.8% [1] , without pretreatment)
Excipient
Lactose 65 g, Microcrystalline Cellulose 40 g, Carboxy-
methyl starch sodium 6 g, Sodium sulfite 0.15 g, Povidone
K30 3 g, Magnesium Stearate 0.7 g, Colloidal silica 0.2 g
Medicament
85% Aqueous ethanol solution 36.7 g
having
acidic
solution
Solvent
78% Aqueous ethanol solution 40.3 g (31.3% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 4.1 g
(molar ratio of it to aripiprazole is 0.50),
Citric Acid Monohydrate 2.42 g
(molar ratio of it to aripiprazole is 0.52)
Alkalizer
20% Aqueous sodium hydroxide solution 4.45 g
(molar ratio of it to the acidifier is 0.98)
Preparation
Mix 33 g 95% ethanol, aqueous hydrochloric acid solution,
Technology
povidone, citric acid monohydrate and aripiprazole to
prepare medicament having acidic solution; add sodium
sulfite and 20% amount of lactose when stirring; add
aqueous sodium hydroxide solution when stirring to get
mixture. Add the mixture into the mixed powder of 80%
amount of lactose, 50% amount of carboxymethyl starch
sodium and microcrystalline cellulose and carry out
stirring granulation; finish granule after drying wet
granules; add magnesium stearate, colloidal silica and
50% amount of carboxymethyl starch sodium, mix
uniformly and press.
Example 26
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0069]
[0000]
Drug
Aripiprazole 5 g (4.3% [1] , without pretreatment)
Excipient
Mannitol 60 g, Microcrystalline Cellulose 40 g, Carboxy-
methyl starch sodium 6 g, Sodium bisulfite 0.1 g,
Sodium citrate dihydrate 0.05 g, Povidone K30 3 g,
Magnesium Stearate 0.8 g
Medicament
76% Aqueous ethanol solution 17.6 g
having
acidic
solution
Solvent
62% Aqueous ethanol solution 21.5 g (18.6% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 4.0 g
(molar ratio of it to aripiprazole is 0.98)
Alkalizer
10% Aqueous sodium hydroxide solution 4.29 g
(molar ratio of it to hydrochloric acid is 9.8)
Preparation
Mix 14 g 95% ethanol, aqueous hydrochloric acid solu-
Technology
tion, povidone K30 and aripiprazole to prepare medica-
ment having acidic solution; stir when add sodium
bisulfite, sodium citrate dihydrate and 20% amount of
mannitol when stirring, then add aqueous sodium hydrox-
ide solution when stirring to get mixture. Add the
mixture into the mixed powder of 80% amount of
mannitol, 50% amount of carboxymethyl starch sodium
and microcrystalline cellulose and carry out stirring
granulation; finish granule after drying wet granules; add
magnesium stearate and 50% amount of carboxymethyl
starch sodium, mix uniformly and press.
Example 27
Prescription and Preparation Method of Aripiprazole Tablets (5 Mg/Tablet) (Unit: Gram)
[0070]
[0000]
Drug
Aripiprazole 5 g (4.4% [1] , without pretreatment)
Excipient
Lactose 60 g, Microcrystalline Cellulose 20 g, Starch 20 g,
Sodium sulfite 0.05 g, Povidone K12 3 g, Hydroxypropyl
cellulose 8 g, Magnesium Stearate 0.8 g, Colloidal silica
0.2 g
Medicament
49% Aqueous ethanol solution 19.4 g
having
acidic
solution
Solvent
41% Aqueous ethanol solution 23.4 g (20.4% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 0.41 g
(molar ratio of it to aripiprazole is 0.10)
Citric Acid Monohydrate 2.16 g
(molar ratio of it to aripiprazole is 0.92)
Alkalizer
10% Aqueous sodium hydroxide solution 4.4 g
(molar ratio of it to the acidifier is 0.99)
Preparation
Mix 19 g 50% ethanol, aqueous hydrochloric acid solution,
Technology
povidone K12, citric acid monohydrate and aripiprazole
to prepare medicament having acidic solution; add sodium
sulfite and 30% amount of lactose when stirring, then add
aqueous sodium hydroxide solution when stirring to get
mixture. Add the mixture into the mixed powder of 70%
amount of lactose, starch, hydroxypropyl cellulose and
microcrystalline cellulose and carry out stirring granula-
tion; finish granule after drying wet granules; add
magnesium stearate and colloidal silica, mix uniformly
and press.
Example 28
Prescription and Preparation Method of Aripiprazole Tablets (10 Mg/Tablet) (Unit: Gram)
[0071]
[0000]
Drug
Aripiprazole 5 g (4.0% [1] , without pretreatment)
Excipient
Lactose 70 g, Microcrystalline Cellulose 40 g,
Carboxymethyl starch sodium 6 g, Sodium sulfite 0.2 g,
Povidone K30 2 g, Magnesium Stearate 0.8 g, Colloidal
silica 0.2 g
Medicament
57% Aqueous ethanol solution 19.1 g
having
acidic
solution
Solvent
46% Aqueous ethanol solution 23.3 g (18.4% [2] )
Acidifier
10% Aqueous hydrochloric acid solution 1.2 g
(molar ratio of it to aripiprazole is 0.29)
Citric Acid Monohydrate 1.7 g
(molar ratio of it to aripiprazole is 0.72)
Alkalizer
10% Aqueous sodium hydroxide solution 4.0 g
(molar ratio of it to the acidifier is 0.88)
20% Aqueous sodium carbonate solution
(molar ratio of it to the acidifier is 0.12)
Preparation
Mix 18 g 60% ethanol, aqueous hydrochloric acid solu-
Technology
tion, citric acid monohydrate, povidone K30 and
aripiprazole to prepare medicament having acidic solu-
tion; add sodium sulfite and 20% amount of lactose
when stirring, then add aqueous sodium hydroxide solu-
tion and aqueous sodium carbonate solution when
stirring to get mixture. Add the mixture into the mixed
powder of 80% amount of lactose, 50% amount of
carboxymethyl starch sodium and microcrystalline
cellulose and carry out stirring granulation; finish
granule after drying wet granules; add magnesium
stearate, colloidal silica and 50% amount of carboxy-
methyl starch sodium, mix uniformly and press.
Effect Example 1
Measure Particle Size of Aripiprazole in Aripiprazole Granules Compared by Comparison Examples 1 and 2, Examples 1 and 2
[0072] Test instruments: BT-9300S laser particle size distribution device (Dandong Bettersize Technology Ltd.); BT-800 automatic loop sampling system.
[0073] Test conditions: the medium of the loop sampling system is water, the volume is about 570 ml and the rotating speed of centrifugal pump is 1600 rpm.
[0074] Test method: Appropriate amount of sample is added into the loop sampling system and make the shading rate of the system come up to 15%±10. Treat with ultrasonic dispersion for 3 minutes, gain the average particle size with continuous sampling for 6 times.
[0000]
particle size (μm)
Sample
D[4, 3]
D 10
D 50
D 90
Comparison example 1
87.08
14.22
76.52
179.30
Comparison example 2
22.75
2.06
17.33
49.17
Example 1
12.49
1.36
7.59
35.71
Example 2
4.02
0.91
3.30
7.48
Note:
D[4, 3] is the volume mean diameter; D 10 , D 50 and D 90 are the corresponding particle sizes when the percentage of cumulative particle size distribution is up to 10%, 50% and 90% respectively.
Effect Example 2
Comparison Experiments on Solubility
[0075] (1) Measure the Solubility of Aripiprazole Preparations Prepared by Contrastive Examples 3 and 4, Examples 3˜6,9,10 and 14
[0076] Method of measuring the solubility: take samples, according to solubility mensuration (Chinese Pharmacopoeia 2010 Volume 2 appendix X C Method 2), and 500 ml acetate buffer solution with the pH value of 4.0 (0.05 mol/L acetic acid−0.05 mol/L sodium acetate=16.4:3.6) as solvent. Rotation rate is 75 rpm. Carry on according to the mensuration. Take 5 ml solution at the 10th, 20th, 30th, 45th min respectively, and replenish 5 ml dissolution medium to dissolution cup. Filter the samples and take subsequent filtrate as sample solution. Prepare the reference solution. Detect respectively according to high-performance liquid chromatography (Chinese Pharmacopoeia 2010 Volume 2 appendix V D), and use octadecyl silane chemically bonded silica as filler. Use methanol—0.1% triethylamine solution (90:10) as mobile phase; detect at 255 nm, calculate the solubility of each tablet and record in the table below.
[0000]
Solubility (%)
Example
10 min
20 min
30 min
45 min
Contrastive example 3
33.7
45.3
56.0
73.4
Contrastive example 4
56.1
85.5
95.1
97.8
3
60.8
87.7
97.2
99.1
4
71.4
92.5
98.6
99.8
5
70.4
92.9
98.6
99.7
6
60.2
87.8
94.9
98.8
8
61.8
90.4
95.8
98.7
9
59.2
88.4
95.4
98.1
10
67.9
91.5
97.8
99.5
14
73.7
98.9
99.7
99.8
28
61.1
89.5
98.0
99.3
[0077] The solubility of contrastive example 4 in which aripiprazole goes through microcrystalline processing in advance is better than that of contrastive example 3 in which aripiprazole is coarser, while the solubility of the examples in the present invention (Examples 3-6, 9-10 and 14) are all better than that of contrastive example 4. Wherein, improving the concentration of ethanol in the medicament having acidic solution and increase the dosage of povidone K30 is beneficial (example 5 in which the concentration of ethanol is improved is better than example 6, example 4 in which the concentration of ethanol is improved and the dosage of povidone is increased is better than example 3); improving the ratio of water-solution excipient is beneficial (example 10 is better than example 9); while the solubility of capsule is faster (example 14).
Effect Example 3
Comparison on Stability
[0078] (1) Add samples into a high density polyethylene plastic bottle and pack. After the accelerated test for 3 months at 40′C±2° C. and under the relative humidity of 75%±5%, detect the state, content, solubility and related substance.
[0079] Determination method for content and the related substance: take appropriate dosage of samples and dissolve with ultrasonic shake in mobile phase, prepare the solution containing appropriate dosage of aripiprazole per ml as the test solution and the reference solution. Determination is respectively carried out by high-performance liquid chromatography (Chinese Pharmacopoeia 2010 Volume 2 appendix V D), and use octadecyl silane chemically bonded silica as filler; methanol-acetic acid solution (add 1 ml triethylamine to 1000 ml water, adjust pH to 4.0 with acetic acid) (60:40) as mobile phase. Detection wavelength is 255 nm, The determination of content is according to the external standard method, the determination of the related substance is calculated according to the main component self-calibrated method. The results are recorded in the table below.
[0000]
Solubility at the
Related Substance
State
Content (%)
45 th min (%)
(%)
Prior to
After
Prior to
After
Prior to
After
Prior to
After
Example
acceleration
acceleration
acceleration
acceleration
acceleration
acceleration
acceleration
acceleration
Contrastive 4
White
White
98.9
98.1
97.8
96.3
0.10
0.30
tablet
tablet
4
White
White
98.9
99.1
99.8
99.6
0.04
0.11
tablet
tablet
6
White
White
99.1
99.5
98.8
98.2
0.05
0.10
tablet
tablet
7
White
White
99.6
99.1
99.2
98.6
0.08
0.18
tablet
tablet
8
White
White
100.1
99.7
98.7
99.0
0.05
0.09
tablet
tablet
11
White
White
98.6
99.1
97.9
98.3
0.07
0.12
tablet
tablet
25
White
White
99.3
99.4
99.1
99.4
0.05
0.09
tablet
tablet
28
White
White
99.6
99.3
99.3
99.5
0.04
0.08
tablet
tablet
[0080] The amount of related substances (impurities) in the embodiments where antioxidants are used is significantly lower than that in contrastive example 4 where antioxidants are not used.
[0081] (2) Pack samples with high density polyethylene plastic bottle. After the accelerated test for 20 days at 60° C.±2° C., carry on the detection of state, content and related substance. Determination method is as above.
[0000]
State
Content (%)
Related Substance (%)
Prior to
After
Prior to
After
Prior to
After
Example
acceleration
acceleration
acceleration
acceleration
acceleration
acceleration
Contrastive 4
White
Off-white
98.9
98.4
0.10
0.26
tablet
tablet
4
White
Off-white
98.9
99.3
0.04
0.09
tablet
tablet
6
White
Off-white
99.1
99.3
0.05
0.11
tablet
tablet
7
White
Off-white
99.6
98.9
0.08
0.15
tablet
tablet
11
White
Off-white
98.6
99.1
0.07
0.12
tablet
tablet
14
Content is
Content is
99.5
99.6
0.04
0.09
white tablet
off-white
tablet
21
White fine
Off-white
99.1
99.3
0.05
0.10
particle
fine particle
26
White
Off-white
99.5
99.4
0.04
0.08
tablet
tablet
[0082] The amount of related substances (impurities) in the embodiments where antioxidants are used is significantly lower than that in comparative example 4 where antioxidants are not used.
Effect Example 4 the Relationship Between Particle Size and Prescription & Operating Conditions
[0083] The particle sizes of aripiprazole in samples are tested by the following method, and are relatively compared under the different prescriptions and operating conditions.
[0084] Test instruments: BT-9300S laser particle size distribution device (Dandong Bettersize Technology Ltd.); BT-800 automatic loop sampling system.
[0085] Test condition: the medium of the loop sampling system is water, the volume is about 570 ml and the rotating speed of centrifugal pump is 1600 rpm.
[0086] Test method: Appropriate amount of sample is added into the loop sampling system and make the shading rate of the system come up to 15%±10. Treat with ultrasonic dispersion for 3 minutes. Gain the average particle size with continuous sampling for 6 times.
[0087] D[4,3] is the volume mean diameter; D 10 , D 50 and D 90 are the corresponding particle sizes when the percentage of cumulative particle size distribution is up to 10%, 50% and 90% respectively.
[0088] The comparison experiments and results are as follows: (the concentration of aqueous ethanol solution is the concentration of the solvent contained in the medicament having acidic solution; and other excipients contained in medicament having acidic solution are surfactant and/or solubilizer).
[0089] 1. 10 g Aripiprazole, 5 g Povidone K30, hydrochloric acid, water and ethanol are used to prepare medicament having acidic solution (the molar ratio of hydrochloric acid to aripiprazole is 1:1. The dosage of aqueous ethanol solution is 38.9 g, which is 3.89 times the mass of aripiprazole). 10% Aqueous sodium hydroxide solution (the molar ratio of sodium hydroxide to hydrochloric acid is 1.01) is added when stirring (the linear speed of stirrer is 160 m/min) to prepare the mixture solution and test the particle size of the sample. When the concentration of aqueous ethanol solution is 50%, a 50° C. water-bath is used. The results of comparison experiments refer to table 1.
[0000]
TABLE 1
the comparison of particle sizes
Concentration of
aqueous ethanol
Particle size (μm)
Number
solution (W/W %)
D[4, 3]
D 10
D 50
D 90
1-1
50
25.32
3.98
20.43
44.72
1-2
75
30.19
4.07
26.70
63.13
1-3
85
32.46
4.73
28.59
68.61
1-4
90
28.69
4.23
24.09
59.83
1-5
95
18.93
2.37
16.3
39.06
[0090] Table 1 shows that the particle size is affected by the concentration of aqueous ethanol solution, and the particle size is the smallest when the concentration reaches 95%.
[0091] 2. 10 g Aripiprazole, 30 g anhydrous ethanol, 2 g povidone K30, 8.9 g 10% hydrochloric acid (the molar ratio of hydrochloric acid to aripiprazole is 1.1) are used to prepare medicament having acidic solution. 30 g Lactose is added when stirring, and then 10% aqueous sodium hydroxide solution (the molar ratio of sodium hydroxide to hydrochloric acid is 1.01) is added when stirring to prepare the mixture solution. Test the particle sizes of the prepared samples. The results of comparison experiments refer to table 2.
[0000]
TABLE 2
the comparison of particle sizes
Concentration of
Line speed
aqueous ethanol
of stirrer
Particle size (μm)
Number
solution (W/W %)
(m/min)
D[4,3]
D 10
D 50
D 90
2-1
79
50
37.86
6.27
28.83
83.25
2-2
79
160
33.68
4.16
27.64
72.86
2-3
79
285
29.85
3.41
23.25
66.11
[0092] Table 2 shows that the relationship of the particle size and the stirring speed is as follows: with the increase of the stirring speed, the particle size will have a tendency of increase.
[0093] 3. 10 g Aripiprazole, 30 g anhydrous ethanol, 8.9 g 10% hydrochloric acid (the molar ratio of hydrochloric acid to aripiprazole is 1.1, and the concentration of aqueous ethanol solution is 79%, the dosage of which is 3.89 times the mass of aripiprazole) are used to prepare medicament having acidic solution. Excipient (2) and excipient (1) are added when stirring, and 10% aqueous sodium hydroxide solution (the molar ratio of sodium hydroxide to hydrochloric acid is 1.01) is added when stirring (the line speed of stirrer is 160 m/min) to prepare the mixture solution. Test the particle sizes of the prepared samples. The results of comparison experiments refer to table 3, wherein excipient (1) refers to the main water-soluble carrier, excipient (2) refers to the excipients, surfactant, solubilizer and PEG 6000 contained in the medicament having acidic solution.
[0094] Medicament: (1) refers to the mass ratio of aripiprazole to excipient (1); Medicament: (2) refers to the mass ratio of aripiprazole to excipient (2).
[0000]
TABLE 3
the comparison of particle sizes
Excipient
Excipient
Particle size (μm)
Number
(1)
(2)
Medicament: (1)
Medicament: (2)
D[4,3]
D 10
D 50
D 90
3-1
lactose
—
1:0.5
—
45.21
5.17
32.51
104.83
3-2
lactose
—
1:1
—
40.01
5.79
30.41
88.26
3-3
lactose
—
1:2
—
35.21
5.13
27.2
77.36
3-4
lactose
—
1:3
—
33.78
4.81
27.18
72.6
3-5
lactose
—
1:6
—
23.72
2.73
18.91
51.6
3-6
lactose
—
1:9
—
11.49
2.01
9.54
22.76
3-7
lactose
povidone K30
1:3
1:0.2
33.68
4.16
27.64
72.86
3-8
lactose
povidone K30
1:3
1:1
28.23
3.76
20.42
64.12
3-9
lactose
povidone K30
1:3
1:2
14.85
1.61
11.28
32.9
3-10
lactose
povidone K30
1:3
1:0.5
28.44
3.93
22.47
61.34
3-11
lactose
povidone K30
1:6
1:0.5
15.29
1.46
11.52
48.64
3-12
lactose
povidone K30
1:9
1:0.5
6.73
1.15
5.06
15.52
3-13
lactose
Sodium
1:6
1:0.2
33.08
4.73
27.8
67.26
dodecyl sulfate
3-14
lactose
Tween-80
1:6
1:0.2
21.14
2.69
12.97
51.97
3-15
lactose
PEG 6000
1:6
1:1
17.03
2.52
14.02
36.15
3-16
lactose
PEG 6000
1:6
1:4
7.1
1.66
5.86
14.74
3-17
lactose
Poloxamer 188
1:6
1:0.2
25.12
2.38
16.36
60.45
3-18
lactose
Hydroxypropyl
1:6
1:1
26.73
2.91
16.96
64.78
β-Cyclodextrin
3-19
lactose
Hydroxypropyl
1:6
1:4
18.65
1.78
15.33
41.4
β-Cyclodextrin
[0095] Table 3 shows that when one of the surfactant, solubilizer and water-soluble carrier of solid dispersions is added in the medicament having acidic solution, the particle size will be reduced with the increase of the dosage of the said excipient. (2) When at least two of the surfactant, solubilizer and water-soluble carrier of solid dispersions are added in the medicament having acidic solution, under the case that the dosage of one excipient is unchangeable, the particle size will be reduced with the increase of the dosage of the other excipients; (3) When medicament: lactose is 1:6 and medicament: Tween-80 (or poloxamer or sodium dodecyl sulfate) is 1:0.2, the particle size will be decreased more when Tween-80 is added than poloxamer is, and poloxamer is than sodium dodecyl sulfate is.
[0096] 4. 10 g Aripiprazole, 30 g anhydrous ethanol, 8.9 g 10% hydrochloric acid (the molar ratio of hydrochloric acid to aripiprazole is 1.1, and the concentration of aqueous ethanol solution is 79%, the dosage of which is 3.89 times the mass of aripiprazole) and 5 g povidone K30 are used to prepare medicament having acidic solution. Excipient (1) is added when stirring, and 10% aqueous sodium hydroxide solution (the molar ratio of sodium hydroxide to hydrochloric acid is 1.01) is added when stirring (the line speed of stirrer is 160 m/min) to prepare the mixture solution. Test the particle sizes of the prepared samples. The results of comparison experiments refer to table 4.
[0000]
TABLE 4
the comparison of particle sizes
Excipient
Medicament:
Particle size (μm)
Number
(1)
(1)
D[4,3]
D 10
D 50
D 90
4-1
lactose
1:3
28.44
3.93
22.47
61.34
4-2
lactose
1:6
15.29
1.46
11.52.
48.64.
4-3
lactose
1:9
6.73
1.15
5.06
15.52
4-4
mannitol
1:2
30.68
3.4
22.19
70.32
4-5
mannitol
1:4
25.26
2.24
12.25
66.43
4-6
mannitol
1:6
11.73
1.14
5.07
37.82
4-7
maltitol
1:3
36.85
4.77
27.42
83.74
4-8
maltitol
1:6
25.74
3.02
15.95
64.12
4-9
maltitol
1:9
26.3
2.16
13.06
68.9
4-10
sucrose
1:3
32.33
3.98
25.31
71.7
4-11
sucrose
1:6
31.74
2.78
23.44
73.58
4-12
sucrose
1:9
9.95
0.98
6.61
22.56
[0097] Table 4 shows that (1) when one of mannitol, lactose, maltitol and sucrose is added in the medicament having acidic solution, the particle size will be reduced with the increase of the dosage of the said excipient; (2) When small particle size of aripiprazole is required, mannitol is better than lactose, lactose is better than maltitol, and maltitol is better than sucrose.
[0098] 5. Take part of the mixture solution prepared by the example above, add 4 times the amount of excipient (1) that is previously added to each prescription and carry out stirring granulation. Finish granule after drying wet granules. Test the particle size of the sample. The results of comparison experiments refer to table 5.
[0000]
TABLE 5
the comparison of particle sizes
Particle size (μm)
Number
Excipient (1)
Excipient (2)
D[4,3]
D 10
D 50
D 90
3-6
lactose
—
10.12
1.93
8.17
19.34
3-9
lactose
Povidone K30
13.29
1.26
10.5
25.34.
3-14
lactose
Tween-80
17.73
2.14
10.06
38.62
3-16
lactose
PEG 6000
6.23
1.19
4.15
12.33
4-6
mannitol
Povidone K30
9.38
1.02
4.31
27.89
4-8
maltitol
Povidone K30
22.85
2.76
12.49
50.75
4-11
sucrose
Povidone K30
28.56
2.14
20.48
58.21
[0099] 6. Repeat Tests and Results
[0100] 10 g Aripiprazole, 30 g anhydrous ethanol, 8.5 g 10% aqueous hydrochloric acid (the molar ratio of hydrochloric acid to aripiprazole is 1.05) and 5 g povidone K30 are used to prepare medicament having acidic solution. 60 g Lactose is added when stirring (the line speed of stirrer is 160 m/min), and 9.3 g 10% aqueous sodium hydroxide solution (the molar ratio of sodium hydroxide to hydrochloric acid is 1.0) is added quickly, keep stirring for 2 mins to prepare the mixture solution, and then 340 g lactose is added, stir until soft material is prepared, and carry out extrusion granulation, finish granule after drying wet granules, test the particle size of the sample. The experiment is repeated for five times and compare the results in table 6.
[0000]
TABLE 6
the comparison of particle sizes
Particle size (μm)
Number
D[4, 3]
D 10
D 50
D 90
6-1
16.55
1.46
7.17
49.05
6-2
12.26
1.47
7.06
31.51
6-3
14.01
1.38
6.85
40.79
6-4
13.35
1.38
6.75
37.69
6-5
11.28
1.21
6.07
29.54
Average value
13.49
1.38
6.78
37.72
RSD (%)
13.28
6.75
5.68
18.49 | The preparation method includes the following steps: dissolving aripiprazole in an acidic solution having an acidifier so as to obtain a medicament having acidic solution; then, performing a wet granulation on or preparing a suspension with the obtained medicament having acidic solution, an alkalizer, and an excipient so as to obtain the aripiprazole medicament formulation; the excipient comprising an antioxidant. The aripiprazole medicament formulation obtained through the preparation method has a significantly reduced amount of related substances, great solubility, great stability, high bioavailability, reduced individual differences, and enhanced wettability and content uniformity of insoluble medicaments. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a method and catalyst for removing catalyst-poisoning impurities or contaminants such as arsenic, iron and nickel from hydrocarbonaceous fluids, particularly shale oil and fractions thereof. More particularly, the invention relates to a method of removal of such impurities by contacting the fluids with a copper-Group VIA metal-alumina catalyst. The catalyst may be used as a guard bed material in a step preceding most refining operations, such as desulfurization, denitrogenation, catalytic hydrogenation, etc.
Due to scarcity of other hydrocarbon fuels and energy resources in general, shale oil and other hydrocarbonaceous fluids such as those derived from coal, bituminous sands, etc., are expected to play an increasing role in the production of commercial hydrocarbon fuels in the future. Substantial effort has been devoted to the development of cost-efficient refining techniques for the processing of these hydrocarbonaceous fluids. Frequently, these fluids contain contaminants that poison and deactivate expensive and sensitive upgrading catalysts used in hydrogenation and other refining steps to which these hydrocarbonaceous fluids must be subjected before they can be satisfactorily used as sources of energy. In addition, the removal of contaminants such as arsenic may be necessary for environmental protection if the hydrocarbonaceous fluids are employed as fuels, as these contaminants form poisonous compounds.
The prior art has included several methods of removing arsenic from hydrocarbonaceous fluids, such as that described in U.S. Pat. No. 2,778,779 to Donaldson issued on June 14, 1952. Such methods have included the use of metal oxides to remove arsenic from streams of naturally occurring crude oil.
Other processes have been developed for the removal of arsenic present in the parts per billion range from naphthas in order to protect sensitive reforming catalysts. Unfortunately, such processes cannot be applied to shale and other hydrocarbonaceous fluids which often have arsenic concentrations as high as 60 ppm.
Also known, are washing processes employing aqueous caustic solutions to precipitate arsenic salts from the hydrocarbonaceous fluid and extract them into the aqueous phase. See, e.g. U.S. Pat. No. 2,779,715 to Murray issued on Jan. 29, 1957 and D. J. Curtin et al, "Arsenic and Nitrogen Removal during Shale Oil Upgrading", A.C.S. Div. Fuel Chem., No. 23(4), 9/10-15/78. These processes, however, are relatively expensive, cause a substantial amount of fluid to be lost to the aqueous phase, contaminate the hydrocarbon fluid with aqueous solution and present a problem with regard to the disposal of waste caustic solution.
Many patents have issued which are directed to use of a metallic oxide and/or sulfide catalyst such as iron, nickel, cobalt or molybdenum oxide or sulfide or composites thereof on an alumina carrier to remove arsenic and other contaminants from shale oil. See, e.g. U.S. Pat. No. 4,003,829 to Burget et al issued on Jan. 18, 1977, U.S. Pat. No. 4,141,820 to Sullivan issued on Feb. 27, 1979 and U.S. Pat. Nos. 3,954,603 to Curtin, 3,804,750 to Myers and 4,046,674 to Young. While these processes are effective, they employ relatively sophisticated and relatively expensive catalysts which considerably contribute to the processing costs of shale oil.
U.S. Pat. No. 4,354,927 to Shih et al issued on Oct. 19, 1982 describes the removal of catalyst poisoning contaminants such as arsenic and selenium from hydrocarbonaceous fluids particularly shale oil by contact with high-sodium alumina in the presence of hydrogen; saturation of conjugated diolefins is also effected.
Japan Pat. Nos.: 5,6095-985; 5,6092-991; and 5,4033-503 to Chiyoda Chemical Engineering Company of Japan describe Group IB catalysts for demetalation; however, these utilize specific supports (not alumina).
The Bearden, Jr. et al U.S. Pat. No. 4,051,015 describes a copper chloride demetalation catalyst.
OBJECTS
It is an object of this invention to provide an improved catalyst and method for removing arsenic from hydrocarbonaceous fluids such as shale oil.
It is another object of this invention to provide an improved catalyst and method for removing arsenic from a hydrocarbonaceous fluid having a relatively high arsenic content.
It is a further object of this invention to provide a catalyst and process for removal of arsenic which does not entail use of an aqueous phase and mixing of said aqueous phase with the hydrocarbon.
It is yet another object of this invention to provide an improved catalyst and method for removing arsenic and other contaminants from hydrocarbonaceous fluids, which method is inexpensive and does not substantially contribute to the processing cost of the fluids.
These and other objects will become apparent from the specification which follows.
SUMMARY
In accordance with one aspect of the invention, there is provided a method for reducing the content of at least one of arsenic, iron and nickel in a hydrocarbonaceous fluid by contacting the fluid with a particulate catalyst consisting essentially of an oxide or sulfide of copper and an oxide or sulfide of a Group VIA metal on a porous alumina support in the presence of hydrogen under sufficient metal reducing conditions. Such metal reducing conditions may involve, e.g., a temperature ranging from about 400° to 900° F., a pressure ranging from about 100 to 3000 psig, and a LHSV of from about 0.1 to 10. By means of the metal reducing process of the present invention, a relatively small amount of hydrogen may be consumed while removing a relatively large amount of metals.
According to another aspect of the invention, there is provided a particulate catalyst consisting essentially of an oxide or sulfide of copper and an oxide or sulfide of a Group VIA metal on a porous alumina support, wherein the total weight of the oxides or sulfides of copper and the oxides or sulfides of the Group VIA metal are present in an amount ranging from about 20 to 75 weight percent, based on the total catalyst, the remainder of the catalyst being essentially alumina. This catalyst is particularly suitable for reducing the content of at least one of arsenic, iron and nickel in a hydrocarbonaceous fluid by contacting the fluid with the catalyst in the presence of hydrogen under sufficient metal reducing conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph showing the removal of arsenic from shale oil by a copper-molybdenum-alumina catalyst as compared with other demetalation catalysts.
FIG. 2 is a graph showing the removal of nickel from shale oil by a copper-molybdenum-alumina catalyst as compared with other demetalation catalysts.
FIG. 3 is a graph showing the removal of iron from shale oil by a copper-molybdenum-alumina catalyst as compared with other demetalation catalysts.
FIG. 4 is a graph showing demetalation vs. hydrogen consumption for shale oil with a copper-molybdenum-alumina catalyst as compared with other demetalation catalysts.
DETAILED DESCRIPTION
The Group VIA metals referred to herein correspond to the elements of Group VIA of the Periodic Chart of the Elements. The Periodic Chart referred to herein is that version officially approved by the United States National Bureau of Standards (NBS) and the International Union of Pure and Applied Chemists (IUPAC), the elements of Group VIA being chromium (Cr), molybdenum (Mo) and tungsten or wolfram (W). Preferred Group VIA metals are molybdenum and tungsten, especially molybdenum.
Examples of preferred catalysts according to the present invention contain from about 20 to 65, most especially 38 to 46, weight percent CuO and from about 4 to 12, most especially 7 to 9 weight percent MoO 3 . Catalysts in accordance with the present invention may have a pore volume within the range of about 0.4 cc/g and 0.8 cc/g and a surface area within the range of 150 to 250 m 2 /g.
By way of example, retorted shale oil can be partially upgraded by contacting the demineralized ("desalted") oil with a CuMo/Al 2 O 3 guard chamber catalyst in the presence of hydrogen at temperatures of 500°-700° F. In this process, a 42 wt. % copper oxide; 8 wt. % molybdena on alumina catalyst shows demetalation activity equal to or better than conventional hydrotreating catalysts, but requires less hydrogen consumption. As discussed more fully hereinafter, the catalyst has higher nickel removal activity than other (nickel-containing) catalysts. This may be especially significant for in-situ derived shale oils which tend to have higher nickel contents than conventional retorted oils. Since the catalyst has some hydrogenation activity, it effectively lowers the conjugated diolefin content at mild conditions--something that a Ni/Al 2 O 3 or Cu/Al 2 O 3 catalyst cannot achieve if the feedstock is high in sulfur (≧0.5 wt. %).
Retorted shale oil contains a large number of trace metals such as As, Fe, Ni, V, Co, Se and Zn; As and Fe are the predominant trace elements (>20 ppm). These metals present several processing and product problems:
some arsenic compounds in shale oil are water soluble and can cause pipeline corrosion;
when shale oil is upgraded by delayed coking, most of the metals are rejected in the coke, result in a lower quality coke;
upgrading catalysts are irreversibly poisoned by metals deposition;
when burned directly as a fuel, shale oil has potential As 2 O 3 emission problems.
As mentioned previously, there are many methods reported in the literature for arsenic removal, adsorption, extraction, thermal treatment, and chemical additives. Relative to metals in petroleum, arsenic in shale oil is very reactive. Commercial hydrotreating catalysts, when fresh, can easily reduce the arsenic and other metals in shale oil to less than 0.1 ppm under normal hydrotreating conditions (T≧725° F. and LHSV≦0.8). Since metals poison the catalyst's hydrotreating activity, upstream metals removal is preferred.
Most guard chamber operations are carried out in the presence of hydrogen. Although arsenic removal is relatively insensitive to hydrogen partial pressure (i.e. kα(P/P o ) 0 .4) in the 400-2200 psi range, plugging problems have been encountered at lower pressures (<1000 psi). The major catalysts--nickel, cobalt, iron or copper--have poor hydrogenative activity at lower temperatures (≦400° F.) and consequently, cannot eliminate the fouling problems.
The invention may be practiced in a guard bed chamber preferably having a fixed bed of porous particulate material, but a moving bed may also be used. An example of such a particulate material is a copper-molybdenum-alumina catalyst.
The guard bed may be situated in a guard chamber, a closed metal vessel capable of being pressurized. The particles must be capable of promoting deposition of the contaminants thereon when contacted by the hydrocarbonaceous feed under a reducing atmosphere provided by hydrogen at a pressure between 100 and 3000 psig, preferably between 400 and 2500 psig, and at a temperature between 400° and 900° F., preferably between 500° and 750° F.
The hydrocarbonaceous feed is preferably admixed with hydrogen at a ratio ranging from 1000 to 10,000 standard cubic feet (scf) of H 2 per barrel (b) of feed and preferably 2000 to 5000 scf of H 2 /b of feed and the admixed feed is contacted with the particles for a time sufficient to reduce the arsenic and other contaminant content to acceptable levels.
The quantity of material in the guard bed should be sufficient to keep the Liquid Hourly Space Velocity (LHSV), measured in units of volumetric flow rate of feed per unit volume of catalyst, between the values of 0.1 and 10 and preferably between those of 0.5 and 3. This LHSV range corresponds to a residence time for the feed in the guard bed ranging between 0.1 and 10 hours and preferably 0.3 to 2 hours.
The invention may be further illustrated by the Examples which follow:
EXAMPLE 1
Catalyst Preparation
[42% CuO-8% MoO 3 -50% Al 2 O 3 ]
A catalyst was prepared in the following manner: 211 ml. of solution containing 73.0 grams ammonium heptamolybdate (81.5% MoO 3 ) were blended in a muller-mixer with 535 grams of alpha alumina monohydrate powder, a product commercially available as Kaiser Substrate Alumina (SA) from Kaiser Chemicals. Then 454 grams of cupric carbonate (68.85% CuO) were blended into the mixture, after which 200 ml. water were added. The mixture was extruded to one-thirty second inch diameter cylinders, dried at 250° F. and calcined two hours at 800° F.
The catalyst had the following properties:
______________________________________Density, g/ccPacked 0.73Particle 1.41Real 4.57Pore Volume (PV), cc/g 0.489Surface Area, m/g 208Avg. Pore Diameter, Å 94Pore Size Distribution% of PV in Pores of 0-50 Å Diameter 17 50-100 22100-150 21150-200 23200-300 11300+ 6______________________________________
EXAMPLE 2
The catalyst of Example 1 was used in five runs for the demetalation of Occidental Shale Oil. Data for this example are shown in Table 1.
TABLE 1______________________________________Demetalation of Occidental Shale Oil over (CuMo/Al.sub.2 O.sub.3) CHG 1 2 3 4 5______________________________________Reactor Conditions lTemperature, °F. -- 504 556 608 650 701Pressure, psig -- 2200 2200 2200 2200 2200LHSV, vff/hr/vcat -- 1.8 1.8 1.8 1.9 2.0Days on Stream -- 1.3 2.1 2.9 3.6 4.4TLP PropertiesGravity, °API 23.0 23.2 24.6 24.8 25.1 26.4Hydrogen, wt. % 12.04 12.10 12.40 12.35 12.41 12.70Nitrogen, wt. % 1.61 1.47 1.46 1.35 1.32 1.29Sulfur, wt. % 0.67 0.57 0.52 0.50 0.37 0.25Arsenic, ppm 20.0 12.0 11.0 9.6 6.4 3.3Iron, ppm 68.0 4.1 3.3 2.2 1.4 0.9Nickel, ppm 11.0 10.0 9.4 8.4 4.7 1.5H.sub.2 Consumption, scf/b -- 28 -- 197 244 429______________________________________
Three catalysts are compared for processing Occidental shale oil. Shell 324 and Harshaw Ni-3266E are felt to be relatively active commercial catalysts for demetalation. Key results are shown in FIGS. 1-4. The results indicate:
The catalyst of Example 1 is less active than Shell 324 for dearsenation, but more active than Harshaw Ni-3266E;
The catalyst of Example 1 is more active than the other catalysts for iron and nickel removal. The approximate 100° F. improvement in iron removal activity is especially significant as iron is the most predominant trace metal in shale oil. Nickel removal is especially important for in-situ generated shale oils which tend to have higher nickel concentrations.
The demetalation/hydrogen consumption selectivity of the catalyst of Example 1 is better than Harshaw Ni-3266E or Shell 324. The selectivity could probably be improved by optimizing the molybdenum content in the catalyst of Example 1.
About 70% of the arsenic removed was retained on the catalyst. This is similar to the amount retained on nickel-containing catalysts. The arsenic compounds are speculated to be reacting with the copper to form stable complexes. Copper-arsenic complexes are abundant in nature (e.g., enargite-3CuS.As 2 S 5 ) and are often a by-product of copper smelting operations. (Note Kirk-Othmer, Encyclopedia of Chemical Technology, Second Edition, Vol. 2, p. 721.
Features of the process of the present invention include the following:
Uses copper-Group VIA metal-alumina catalyst for demetalation.
Retains arsenic on catalyst--probably in the form of copper-arsenic complexes.
Has higher iron and nickel removal activities than nickel-containing demetalation catalysts.
Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives and variations that fall within the spirit and scope of the appended claims. | There is provided a method and catalyst for removing catalyst-poisoning impurities or contaminants such as arsenic, iron and nickel from hydrocarbonaceous fluids, particularly shale oil and fractions thereof. More particularly there is provided a method of removal of such impurities by contacting the fluids with a copper-Group VIA metal-alumina catalyst. For example, a copper-molybdenum-alumina catalyst may be used as a guard bed material in a step preceding most refining operations, such as desulfurization, denitrogenation, catalytic hydrogenation, etc. | 2 |
This is a continuation of application(s) Ser. No. 08/ 790,050 filed on Jan. 28, 1997, now abandoned which is a continuation of application Ser. No. 08/390,446 filed on Feb. 17, 1995, abandoned.
FIELD OF THE INVENTION
The invention relates to systems and methods for pacing and mapping the heart for diagnosis and treatment of cardiac conditions.
BACKGROUND OF THE INVENTION
Normal sinus rhythm of the heart begins with the sinoatrial node (or "SA node") generating a depolarization wave front. The impulse causes adjacent myocardial tissue cells in the atria to depolarize, which in turn causes adjacent myocardial tissue cells to depolarize. The depolarization propagates across the atria, causing the atria to contract and empty blood from the atria into the ventricles. The impulse is next delivered via the atrioventricular node (or "AV node") and the bundle of HIS (or "HIS bundle") to myocardial tissue cells of the ventricles. The depolarization of these cells propagates across the ventricles, causing the ventricles to contract.
This conduction system results in the described, organized sequence of myocardial contraction leading to a normal heartbeat.
Sometimes aberrant conductive pathways develop in heart tissue, which disrupt the normal path of depolarization events. For example, anatomical obstacles in the atria or ventricles can disrupt the normal propagation of electrical impulses. These anatomical obstacles (called "conduction blocks") can cause the electrical impulse to degenerate into several circular wavelets that circulate about the obstacles. These wavelets, called "reentry circuits," disrupt the normal activation of the atria or ventricles. As a further example, localized regions of ischemic myocardial tissue may propagate depolarization events slower than normal myocardial tissue. The ischemic region, also called a "slow conduction zone," creates errant, circular propagation patterns, called "circus motion." The circus motion also disrupts the normal depolarization patterns, thereby disrupting the normal contraction of heart tissue.
The aberrant conductive pathways create abnormal, irregular, and sometimes life-threatening heart rhythms, called arrhythmias. An arrhythmia can take place in the atria, for example, as in atrial tachycardia (AT) or atrial flutter (AF). The arrhythmia can also take place in the ventricle, for example, as in ventricular tachycardia (VT).
In treating arrhythmias, it is essential that the location of the sources of the aberrant pathways (called arrhthymia substrate) be located. Once located, the tissue in the arrthymia substrate can be destroyed, or ablated, by heat, chemicals, or other means. Ablation can remove the aberrant conductive pathway, restoring normal myocardial contraction.
Today, physicians examine the propagation of electrical impulses in heart tissue to locate the arrhthymia substrate. The techniques used to analyze the substrate, commonly called "mapping," identify regions in the heart tissue, which can be ablated or otherwise altered, such as by injection of cells or genes, to treat the arrhythmia.
One form of conventional cardiac tissue mapping techniques uses multiple electrodes positioned in contact with epicardial heart tissue to obtain multiple electrograms. The physician stimulates myocardial tissue by introducing pacing signals and visually observes the morphologies of the electrograms recorded during pacing, which this Specification will refer to as "paced electrograms." The physician visually compares the patterns of paced electrograms to those previously recorded during an arrhythmia episode to locate tissue regions appropriate for ablation. These conventional mapping techniques require invasive open heart surgical techniques to position the electrodes on the epicardial surface of the heart.
Conventional epicardial electrogram processing techniques used for detecting local electrical events in heart tissue are often unable to interpret electrograms with multiple morphologies. Such electrograms are encountered, for example, when mapping a heart undergoing ventricular tachycardia (VT). For this and other reasons, consistently high correct foci identification rates (CIR) cannot be achieved with current multi-electrode mapping technologies.
Another form of conventional cardiac tissue mapping technique, called pace mapping, uses a roving electrode in a heart chamber for pacing the heart at various endocardial locations. In searching for the VT foci, the physician must visually compare all paced electrocardiograms (recorded by twelve lead body surface electrocardiograms (ECG's)) to those previously recorded during an induced VT. The physician must constantly relocate the roving electrode to a new location to systematically map the endocardium.
These techniques are complicated and time consuming. They require repeated manipulation and movement of the pacing electrodes. At the same time, they require the physician to visually assimilate and interpret the electrocardiograms.
There thus remains a real need for cardiac mapping and ablation systems and procedures that simplify and automate the analysis of electrograms and the use of electrograms to locate appropriate arrhythmogenic substrate.
SUMMARY OF THE INVENTION
A principal objective of the invention is to provide improved probes and methodologies to examine heart tissue morphology quickly and accurately.
The invention provides systems and methods for determining appropriate ablation sites by comparing electrograms obtained during an arrhythmia episode to those obtained during pacing and mapping.
One aspect of the invention provides an analog or digital processing element and associated method for analyzing electrograms. The element and method input a first number of electrogram samples over time during a cardiac event of known diagnosis, such as, for example, VT or AT. The element and method also input a second number of paced electrogram samples over time. The element and method cross-correlate the first number of event-specific electrogram samples with the second number of paced electrogram samples. The element and method generate an output based upon the cross-correlation. The output aids in identifying potentially appropriate tissue sites for ablation.
In a preferred embodiment, the element and method use an array of multiple electrodes supported within a heart chamber in operative association with a region of endocardial tissue. The element and method condition the electrode array to record at each electrode a first number of electrogram samples over time during the cardiac event of known diagnosis. The element also sequentially conditions different ones of the multiple electrodes on the array to emit a pacing signal and to record at each electrode on the array a second number of paced electrogram samples over time. In this implementation, the element and method individually cross-correlate, for each different one of the pacing signal-emitting electrodes, the first number of event-specific electrogram samples with the second number of paced electrogram samples. The element and method generate an output for each electrode on the array.
In a preferred embodiment, the output comprises a numerical set of cross-correlation functions.
Another aspect of the invention provides an analog or digital element and associated method for analyzing electrocardiograms. The element and associated method input a first number of electrocardiogram samples recorded over time during a cardiac event of known diagnosis using multiple body surface electrodes. The element and method also input a second number of paced electrocardiogram gram samples recorded over time using the multiple body surface electrodes. The element and method cross-correlate the first number of event-specific electrocardiogram samples with the second number of paced electrocardiogram samples and generate an output based upon the cross-correlation. The output aids in identifying site or sites potentially appropriate for ablation.
In a preferred embodiment, the output comprises a numerical cross-correlation function.
Other features and advantages of the inventions are set forth in the following Description and Drawings, as well as in the appended Claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a diagrammatic view of a system, which embodies the features of the invention, for accessing a targeted tissue region in the body for diagnostic or therapeutic purposes;
FIG. 1B is a diagrammatic view of the system shown in FIG. 1A, with the inclusion of a roving pacing probe and additional features to aid the physician in conducting diagnosis and therapeutic techniques according to the invention;
FIG. 2 is an enlarged perspective view of a multiple-electrode structure used in association with the system shown in FIG. 1;
FIG. 3 is an enlarged view of an ablation probe usable in association with the system shown in FIGS. 1A and 1B;
FIG. 4A is a diagrammatic view of the process controller shown in FIGS. 1A and 1B, which locates by electrogram matching a site appropriate for ablation;
FIG. 4B is a schematic view of a slow conduction zone in myocardial tissue and the circular propagation patterns (called circus motion) it creates;
FIG. 5 is a flow chart showing a cross correlation technique that the process controller shown in FIG. 4A can employ for cross-correlating electrograms according to the invention; and
FIGS. 6A and 6B and 6C are representative electrogram morphologies;
FIG. 7A is the result of cross-correlating the electrogram shown in FIG. 6A with the electrogram shown in FIG. 6B in accordance with the cross correlation coefficient technique shown in FIG. 5; and
FIG. 7B is the result of cross-correlating the electrogram shown in FIG. 6A with the electrogram shown in FIG. 6C in accordance with the cross correlation coefficient technique shown in FIG. 5.
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.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1A shows the components of a system 10 for analyzing body tissue biopotential morphologies for diagnostic or therapeutic purposes. The illustrated embodiment shows the system 10 being used to examine the depolarization of heart tissue that is subject to an arrhythmia. In this embodiment, the system 10 serves to locate an arrhythmogenic substrate for removal by ablation. The invention is well suited for use in conducting electrical therapy of the heart.
Still, it should be appreciated that the invention is applicable for use in other regions of the body where tissue biopotential morphologies can be ascertained by analyzing electrical events in the tissue. For example, the various aspects of the invention have application in procedures for analyzing brain or neurologic tissue.
FIG. 1A shows the system 10 analyzing endocardial electrical events, using catheter-based, vascular access techniques. Still, many aspects of the invention can be used in association with techniques that do not require any intrusion into the body, like surface electrocardiograms or electroencephalograms. Many of the aspects of the invention also can be used with invasive surgical techniques, like in open chest or open heart surgery, or during brain surgery.
In particular, FIG. 1A shows the system 10 analyzing electrical events within a selected region 12 inside a human heart. FIGS. 1A and 1B generally show the system 10 deployed in the left ventricle of the heart. Of course, the system 10 can be deployed in other regions of the heart, too. It should also be noted that the heart shown in the FIG. 1 is not anatomically accurate. FIGS. 1A and 1B show the heart in diagrammatic form to demonstrate the features of the invention.
The system 10 includes a mapping probe 14 and an ablation probe 16. In FIG. 1A, each is separately introduced into the selected heart region 12 through a vein or artery (typically the femoral vein or artery) through suitable percutaneous access. Alternatively, the mapping probe 14 and ablation probe 16 can be assembled in an integrated structure for simultaneous introduction and deployment in the heart region 12.
Further details of the deployment and structures of the probes 14 and 16 are set forth in pending U.S. patent application Ser. No. 08/033,641, filed Mar. 16, 1993, entitled "Systems and Methods Using Guide Sheaths for Introducing, Deploying, and Stabilizing Cardiac Mapping and Ablation Probes."
The mapping probe 14 has a flexible catheter body 18. The distal end of the catheteribody 18 carries a three dimensional multiple-electrode structure 20. In the illustrated embodiment, the structure 20 takes the form of a basket defining an open interior space 22 (see FIG. 2). It should be appreciated that other three dimensional structures, or one dimensional or two dimensional arrays, could also be used.
As FIG. 2 shows, the illustrated basket structure 20 comprises a base member 26 and an end cap 28. Generally flexible splines 30 extend in a circumferentially spaced relationship between the base member 26 and the end cap 28.
The splines 30 are preferably made of a resilient, biologically inert material, like Nitinol metal or silicone rubber. The splines 30 are connected between the base member 26 and the end cap 28 in a resilient, pretensed, radially expanded condition, to bend and conform to the endocardial tissue surface they contact. In the illustrated embodiment (see FIG. 2), eight splines 30 form the basket structure 20. Additional or fewer splines 30 could be used.
The splines 30 carry an array of electrodes 24. In the illustrated embodiment, each spline 30 carries eight electrodes 24. Of course, additional or fewer electrodes 24 can be used. Similary, surface electrodes 24' also be used.
A slidable sheath 19 is movable along the axis of the catheter body 18 (shown by arrows in FIG. 2). Moving the sheath 19 forward causes it to move over the basket structure 20, collapsing it into a compact, low profile condition for introducing into the heart region 12. Moving the sheath 19 rearward frees the basket structure 20, allowing it to spring open and assume the pretensed, radially expanded position shown in FIG. 2. The electrodes are urged into contact against the surrounding heart tissue.
Further details of the basket structure are disclosed in pending U.S. patent application Ser. No. 08/206,414, filed Mar. 4, 1994, entitled "Multiple Electrode Support Structures."
In use, the electrodes 24 sense electrical events in myocardial tissue for the creation of electrograms. The electrodes 24 are electrically coupled to a process controller 32 (see FIG. 1A). A signal wire (not shown) is electrically coupled to each electrode 24. The wires extend through the body 18 of the probe 14 into a handle 21, in which they are coupled to an external multiple pin connector 23. The connector 23 electrically couples the electrodes to the process controller 32.
Alternatively, multiple electrode structures can be located epicardially using a set of catheters individually introduced through the coronary vasculature (e.g., retrograde through the aorta or coronary sinus), as disclosed in PCT/US94/01055 entitled "Multiple Intravascular Sensing Devices for Electrical Activity."
The ablation probe 16 (see FIG. 3) includes a flexible catheter body 34 that carries one or more ablation electrodes 36. For the sake of illustration, FIG. 3 shows a single ablation electrode 36 carried at the distal tip of the catheter body 34. Of course, other configurations employing multiple ablation electrodes are possible, as described in pending U.S. patent application Ser. No. 08/287,310, filed Aug. 8, 1994, entitled "Systems and Methods for Ablating Heart Tissue Using Multiple Electrode Elements."
A handle 38 is attached to the proximal end of the catheter body 34. The handle 38 and catheter body 34 carry a steering mechanism 40 for selectively bending or flexing the catheter body 34 along its length, as the arrows in FIG. 3 show.
The steering mechanism 40 can vary. For example, the steering mechanism can be as shown in U.S. Pat. No. 5,254,088, which is incorporated herein by reference.
A wire (not shown) electrically connected to the ablation electrode 36 extends through the catheter body 34 into the handle 38, where it is electrically coupled to an external connector 45. The connector 45 connects the electrode 36 to a generator 46 of ablation energy. The type of energy used for ablation can vary. Typically, the generator 46 supplies electromagnetic radio frequency energy, which the electrode 36 emits into tissue. A radio frequency generator Model EPT-1000, available from EP Technologies, Inc., Sunnyvale, Calif., can be used for this purpose. Alternatively, genes or cells could be injected to improve conduction.
In use, the physician places the ablation electrode 36 in contact with heart tissue at the site identified for ablation. The ablation electrode emits ablating energy to heat and thermally destroy the contacted tissue.
According to the features of the invention, the process controller 32 employs electrogram cross-correlation to automatically locate for the physician the site or sites potentially appropriate for ablation.
I. Electrogram Cross-Correlation
The process controller 32 is operable to sense electrical events in heart tissue and to process and analyze these events to achieve the objectives of the invention. The process controller 32 is also selectively operable to induce electrical events by transmitting pacing signals into heart tissue.
More particularly, the process controller 32 is electrically coupled by a bus 47 to a pacing module 48, which paces the heart sequentially through individual or pairs of electrodes to induce depolarization. Details of the process controller 32 and pacing module 48 are described in copending U.S. patent application Ser. No. 08/188,316, filed Jan. 28, 1994, and entitled "Systems and Methods for Deriving Electrical Characteristics of Cardiac Tissue for Output in Iso-Characteristic Displays."
The process controller 32 is also electrically coupled by a bus 49 to a signal processing module 50. The processing module 50 processes cardiac signals into electrograms. A Model TMS 320C31 processor available from Spectrum Signal Processing, Inc. can be used for this purpose.
The process controller 32 is further electrically coupled by a bus 51 to a host processor 52, which processes the input from the electrogram processing module 50 in accordance with the invention to locate arrhythmogenic substrate. The host processor 32 can comprise a 486-type microprocessor.
According to the invention, the process controller 32 operates in two functional modes, called the sampling mode and the cross-correlation mode.
In the sampling mode, the physician deploys the basket structure 20 in the desired heart region 12. To assure adequate contact is made in the desired region 12, the physician may have to collapse the basket structure 20, rotate it, and then free the basket structure 20. The degree of contact can be sensed by the process controller 32 in various ways. For example, the process controller 32 can condition the pacing module 48 to emit pacing signals through a selected electrode 24 or pair of electrodes 24. The process controller 32 conditions the electrodes 24 and processing module 50 to detect electrograms sensed by a desired number of the electrodes 24. The processing module can also ascertain the desired degree of contact by measuring tissue impedance, as described in copending patent application Ser. No. 08/221,347, filed Mar. 31, 1994, and entitled "Systems and Methods for Positioning Multiple Electrode Structures in Electrical Contact with the Myocardium."
Once the basket structure 20 is properly positioned, the process controller 32 conditions the electrodes 24 and signal processing module 50 to record electrogram samples during a selected cardiac event having a known diagnosis. In the sampling mode, the process controller 32 typically must condition the pacing module 48 to pace the heart until the desired cardiac event is induced. Of course, if the patient spontaneously experiences the cardiac event while the structure 20 is positioned, then paced-induction is not required.
The processor controller 32 saves these electrogram samples in the host processor 52. At the end of the sampling mode, the process controller 32 typically must condition the pacing module 48 to pace terminate the cardiac event, or the physician may apply a shock to restore normal sinus rhythm.
The cross-correlation mode is begun without altering the position of the multiple electrode structure 20 in the heart region 12, so that the electrodes 24 occupy the same position during the cross-correlation mode as they did during the sampling mode.
In the cross-correlation mode, the process controller 32 first conditions the pacing module 48 to pace the heart in a prescribed manner without inducing the cardiac event of interest, while conditioning the signal processing module 50 to record a number of the resulting electrograms. The process controller 32 then operates the host processor 52 to cross-correlate all or a selected number of the resulting paced electrogram samples to all or a selected number of the electrogram samples collected during the sampling mode. Based upon this comparison, the host processor 52 generates an output that identifies the location of the electrode or electrodes 24 on the structure 20 that are close to a potential ablation site.
A. The Sampling Mode
As before generally described, the process controller 32 operates in the sampling mode while the heart is experiencing a selected cardiac event of known diagnosis and the basket structure 20 is retained in a fixed location in the region 12. In the illustrated and preferred embodiment, the selected event comprises an arrhythmia that the physician seeks to treat, for example, ventricular tachycardia (VT), or atrial tachycardia (AT), or atrial fibrillation (AF).
As FIG. 4A shows, during the sampling mode, the signal processing module 50 processes a selected number of event-specific electrogram samples obtained from each electrode during the known cardiac event (designated for the purpose of illustration as El to E3 in FIG. 4A). The event-specific electrogram samples (designated for the purpose of illustration in FIG. 4A as SI to S3) may be recorded unipolar (between an electrode 24 and a reference electrode, not shown) or bipolar (between electrodes 24 on the structure 20). The samples S1 to S3 can comprise one heart beat or a specified number of heart beats. Multiple beats may be averaged to reduce noise, if desired.
The host processor 52 retains the set of event-specific electrogram samples Si to S3 in memory. The processor 52 can, for an individual patient, retain sets of event-specific electrogram samples for different cardiac events. For example, a patient may undergo different VT episodes, each with a different morphology. The processor 52 can automatically detect different VT morphologies and store samples for each VT episode for analysis according to the invention. The samples can be downloaded to external disk memory for off-line cross-correlation at a subsequent time, as will be described later.
B. The Cross-Correlation Mode
In the cross-correlation mode, the process controller 32 operates the pacing module 48 to apply pacing signals sequentially to each of the individual electrodes. The pacing electrode is designated Ep in FIG. 4A.
The pacing signal induces depolarization, emanating at the location of the pacing electrode Ep. The process controller 32 operates the signal processing module 50 to process the resulting paced electrogram samples sensed at each electrode (again designated El to E3 for the purpose of illustration in FIG. 4A) during pacing by the selected individual electrode Ep. The processed paced electrogram samples are designated P1 to P3 in FIG. 4A.
The paced morphology P1 to P3 at each electrode can be from one heart beat or a specified number of heart beats, provided that the length of the morphologies P1 to P3 are not shorter than the length of the event-specific samples Si to S3 for the same electrodes El to E3 obtained during the sampling mode.
Different conventional pacing techniques can be used to obtain the paced morphologies P1 to P3. For example, conventional pace mapping can be used, during which the pace rate is near the arrhythmia rate, but arrhythmia is not induced.
For reasons that will be explained later, conventional entrainment or reset pacing is the preferred technique. During entrainment pacing, the pacing rate is slightly higher than and the period slightly lower than that observed during the arrhythmia event, thereby increasing the rate of the induced arrhythmia event. Further details of entrainment pacing are found in Almendral et al., "Entrainment of Ventricular Tachycardia: Explanation for Surface Electrocardiographic Phenomena by Analysis of Electrograms Recorded Within the Tachy-cardia Circuit," Circulation, vol. 77, No. 3, March 1988, pages 569 to 580, which is incorporated herein by reference.
Regardless of the particular pacing technique used, the pacing stimulus may be monophasic, biphasic, or triphasic.
In the cross-correlation mode, while pacing at an individual one of the electrodes Ep, the host processor 52 cross-correlates the paced morphology P1 to P3 obtained at each electrode El to E3 to the event-specific samples SI to S3 for the same electrode El to E3. The cross-correlations are designated Cl to C3 in FIG. 4A.
Alternatively, the paced morphologies P1 to P3 can be retained in memory or downloaded to external disk memory for cross-correlation at a later time. To accommodate off-line processing, the host processor 52 preferably includes an input module 72 for uploading pregenerated event-specific samples and/or paced samples recorded at an earlier time. The input module 72 allows event specific samples and paced morphologies to be cross-correlated off-line by the host processor 52, without requiring the real time presence of the patient. Alternatively, recorded paced samples can be cross-correlated in real time using event-specific samples generated earlier.
For each pacing electrode Ep(j), the host processor 52 preferably generates a cross-correlation coefficient M COEF (i) for each electrode E(i) from the comparison C(i) of the pacing morphology P(i) to the event-specific morphology S(i) for the same electrode E(i). Preferably, both j and i=1 to n, where n is the total number of electrodes on the three dimensional structure (which, for the purpose of illustration in FIG. 4A, is 3).
The value of the cross-correlation coefficient M COEF (i) is indicative for that electrode E(i) how alike the pacing morphology P(i) is to the event-specific sample S(i) for that electrode E(i). The value of M COEF (I) for each electrode E(i) varies as the location of the pacing electrode Ep(j) changes. Generally speaking, the value of the cross-correlation coefficient M COEF (i) for a given electrode E(i) increases in relation to the closeness of the pacing electrode Ep(j) to the arrhythmogenic foci.
In the illustrated and preferred embodiment (as FIG. 4A shows), while pacing at an individual one of the electrodes Ep(j), the host processor 52 generates from the cross-correlation coefficients M COEF (i) for each electrode E(i) an overall cross-correlation factor M PACE (j) for the pacing electrode Ep(j). The value of the overall cross-correlation factor M PACE (i) for the pacing electrode Ep(j) is indicative of how alike the overall propagation pattern observed during pacing at the electrode Ep(j) is to the overall propagation pattern recorded on the associated event-specific samples.
The process controller 32 operates the pacing module 48 to apply a pacing signal sequentially to each electrode Ep(j) and processes and compares the resulting electrogram morphologies at each electrode E(i) (including Ep(j)) to the event-specific samples, obtaining the cross-correlation coefficients M COEF (i) for each electrode E(i) and an overall cross-correlation factor M PACE (j) for the pacing electrode Ep(j), and so on, until every electrode E(i) serves as a pacing electrode Ep(j).
M PACE (j) for each pacing electrode can be derived from associated cross-correlation coefficients M COEF (i) in various ways.
For example, various conventional averaging techniques can be used. For example, M PACE (j) can be computed as a first order average (arithmetic mean) of M COEF (i) as follows: ##EQU1## where i=1 to n; or as a weighted arithmetic mean, as follows:
M.sub.PACEY(i ) =ΣW(i)M.sub.COEF(i)
where i=1 to n; ΣW(i)=1. If W(i)=1/n, for each i, then the arithmetic mean is obtained.
Generally speaking, the value of the overall cross-correlation factor M PACE (j) increases in relation to the proximity of the particular pacing electrode Ep(j) to a potential ablation site.
By way of overall explanation, for VT, the site appropriate for ablation typically constitutes a slow conduction zone, designated SCZ in FIG. 4B. Depolarization wave fronts (designated DWF in FIG. 4B) entering the slow conduction zone SCZ (at site A in FIG. 4B) break into errant, circular propagation patterns (designated B and C in FIG. 4B), called "circus motion." The circus motions disrupt the normal depolarization patterns, thereby disrupting the normal contraction of heart tissue to cause the cardiac event.
The event-specific samples S(i) record these disrupted depolarization patterns. When a pacing signal is applied to a slow conduction zone, the pacing signal gets caught in the same circus motion (i.e., paths B and C in FIG. 4B) that triggers the targeted cardiac event. A large proportion of the associated pacing morphologies P(i) at the sensing electrodes E(i) will therefore cross-correlate with the associated event-specific samples S(i) recorded during the targeted cardiac event. This leads to a greater number of larger cross-correlation coefficients M COEF (i) and thus to a larger overall cross-correlation factor M PACE (j).
However, when a pacing signal is applied outside a slow conduction zone, the pacing signal does not get caught in the same circus motion. It propagates free of circus motion to induce a significantly different propagation pattern than the one recorded in the event-specific samples S(i). A large proportion of the pacing morphologies P(i) at the sensing electrodes E(i) therefore are not well cross-correlated with the event-specific samples S(i). This leads to a smaller number of larger cross-correlation coefficients M COEF (i) and thus to a smaller overall cross-correlation factor M PACE (j).
This is why the overall cross-correlation factor M PACE (j) becomes larger the closer the pacing electrode Ep(j) is to the slow conduction zone, which is the potential ablation site. The difference in propagation patterns between pacing inside and outside a slow conduction zone is particularly pronounced during entrainment pacing. For this reason, entrainment pacing is preferred.
Ablating tissue in or close to the slow conduction zone prevents subsequent depolarization. The destroyed tissue is thereby "closed" as a possible path of propagation. Depolarization events bypass the ablated region and no longer become caught in circus motion. In this way, ablation can restore normal heart function.
The cross-correlation of pacing morphologies P(i) to event-specific samples S(i) to create the coefficient M COEF (i) and the overall factor M PACE (i) can be accomplished using conventional cross correlation techniques. FIG. 5 shows a cross correlation technique that embodies features of the invention.
For example, when the data sequences of the event-specific samples are time aligned with the data sequences of the paced samples, the cross correlation technique can comprise calculating a cross correlation coefficient. For N pairs of time aligned data {x(n), y(n)}, where x(n) is the event-specific electrogram and y(n) is the paced electrogram, the cross-correlation coefficient can be calculated as follows: ##EQU2##
Any columnar alignment technique can be used to time align the samples. For example, the electrograms could be aligned about the point of largest positive slope.
M COEF (i) is equal to rxy computed for the individual electrode E(i).
When the data sequences between the eventspecific and paced samples are not time aligned, the cross-correlation technique can comprise calculating a cross-correlation function.
This technique uses an appropriate algorithm to calculate for each electrode a cross correlation function between the event-specific samples of electrogram and the samples of the paced electrograms. For identical electrograms, the largest excursion of the cross correlation function will equal 1.0.
Various conventional methods for determining the cross correlation function can be used. For example, for M pairs of data {x(m), y(m)}, where x(m) is the event-specific electrogram and y(m) is the paced electrogram, the correlation function can be calculated as follows: ##EQU3## where m=1 to M; -M≦K≦M, and x and y are the means of the sequences {x} and {y}.
M COEF (i) is equal to the largest excursion of the sequence {rxy(k)} computed for the individual electrode E(i) (i.e., the largest excursion can be either negative or positive, depending upon the degree of intercorrelation).
FIG. 7A shows the cross correlation function for the electrograms of FIG. 6A and FIG. 6B. These electrograms are quite similar, and the cross correlation technique detects this. The largest excursion of the cross correlation function in FIG. 7A is near 1.0 (i.e., it is 0.9694).
Refer now to FIG. 7B, which shows the cross correlation function for the unlike electrograms shown in FIGS. 6A and 6C. The cross correlation technique detects this lack of similarity. The largest excursion in FIG. 7B is negative (i.e., it is -0.7191).
Using either a cross-correlation coefficient or a cross-correlation function to calculate M COEF (i), the pacing electrode Ep(j) having an overall factor M PACE (j) closest to 1.0 is designated to be close to a potential ablation site. When using the cross-correlation function technique, additional information may be contained in the shift parameter k for each electrode.
In one implementation (see FIG. 4A), the host processor 52 sets a target N, which numerically establishes a factor M PACE (j) at which a high probability exists that the pacing electrode is close to a potential ablation site. In a preferred implementation, N=0.8. When M ACE (j) >N, the host processor 52 deems the location of the pacing electrode Ep(j) to be close to a potential site for ablation. When this occurs (as FIG. 4 shows), the host processor 52 transmits a SITE signal to an associated output display device 54 (see FIG. 1A). Through visual prompts, the display device 54 notifies the physician of the location of the pacing electrode Ep(j) and suggests that location as a potential ablation site.
In the preceding embodiments, the endocardially positioned basket structure 20 both paces and senses the resulting electrograms. In an alternative implementation, the process controller 32 can condition the pacing module 48 in the sampling mode to pace the heart and record resulting electrocardiograms using body surface electrodes electrically coupled to the process controller 32.
In this implementation, during the cross-correlation mode, the process controller 32 paces the heart and records resulting paced electrocardiograms with the same body surface electrodes (located in the same position as during the sampling mode) and compared to the event-specific electrocardiogram samples in the manner above described.
In this implementation, the process controller 32 generates the location output based upon comparing the event-specific electrocardiogram samples with the paced electrocardiograms.
The electrograms may or may not be filtered before analysis. A 1 to 300 Hz bandpass filter may be used for filtering. If a filter is used to reduce the noise for an electrogram that is used as a event-specific sample, the same filter must also be used for the paced electrograms, since filtering may alter the electrogram morphology.
The implementation of the system 10 described herein is based largely upon digital signal processing techniques. However, it should be appreciated that a person of ordinary skill in this technology area can easily adapt the digital techniques for analog signal processing.
Various features of the invention are set forth in the following claims. | An analog or digital processing element and associated method analyses electrograms or electrocardiograms to locate sites potentially appropriate for ablation. The element and method compares a first number of electrogram or electrocardiogram samples recorded over time during a cardiac event of known diagnosis with a second number of paced electrogram or electrocardiogram samples recorded over time. The comparison cross-correlates the first number of electrogram samples with the second number of paced electrogram samples. The element and method generate an output based upon the cross-correlation. The element and method compare the output to a predetermined value to determine whether a pacing site for the paced electrogram or electrocardiogram samples is near to a potential ablation site. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to imaging materials, particularly imaging materials which use negative acting photopolymerizable compositions, and more particularly to subbing layers useful on bases which are associated with photopolymerizable compositions.
2. Background of the Art
Photopolymerizable compositions can be used in a number of different types of imaging processes. One important commercial use of photopolymerizable compositions is in the technical area of color proofing, particularly in overlay color proofing. This type of process involves the formation of individual color sheets (e.g., cyan, magenta, yellow and black) from their respective color separation negatives and then overlaying the sheets in register to give a proof of the intended printed image. This type of procedure is disclosed for example in U.S. Pat. Nos. 3,136,637 and 3,671,236. The individual color layers can be formed by pigmented photopolymerizable compositions which, after exposure, are washed in developer solutions with mild scrubbing to provide the individual color images.
In addition to the overlay process, transfer processes can be used in the formation of proofing images. In this process, the individual color images are formed on carrier sheets and transferred, one at a time, onto a surface of a receptor sheet. The individual color images are transferred in register to form a prepress proof of the intended printed image. This type of process is shown in U.S. Pat. No. 4,482,625.
One particular area of problems that has been encountered in photopolymerizable (and photosolubilizable) compositions for use in prepress color proofing has been the critical balance in properties necessary between the substrate and the photopolymerizable composition. The composition must adhere reasonably well to the substrate before imaging, yet be removable in unexposed areas upon development. The exposed areas must also adhere well to the substrate and must adhere more strongly than the unexposed areas. The polymerized areas must also be capable of thermoplastic bonding or adhesive bonding to a receptor sheet with a bond strength greater than its bond strength to the carrier substrate. Without these balances in properties, there would be no faithful reproduction of images and the products would be readily subject to mechanical damage in even the mildly vigorous development processing which color proofing sheets undergo. A major improvement in this area was made by the introduction of polyamide subbing layers between the substrate and the photosensitive layer as shown in U.S. Pat. No. 3,778,272. There the use of methylolated or etherified polyamides soluble in a mixture of alcohol and water is described.
In order to provide higher photographic speed to photopolymeric compositions, it is generally necessary to use higher proportions of monomers and binders with large numbers of photopolymerizable groups thereon. Such binders and compositions using them are shown, for example, in U.S. Pat. Nos. 4,304,923 and 4,228,232. The compositions of these patents having higher monomeric and oligomeric components with lower proportions of film-forming binders provide the higher speed compositions. However, higher concentrations of monomers creates another problem, migration of components from the photosensitive layer into the substrate and/or subbing layer. The migration of the monomers usually carries dyes, photoinitiators and other additives with it. This can greatly vary the adherence properties of the photosensitive layer to the substrate, both before and after exposure. The speed of the photosensitive layer can also adversely vary with time because of the change in the composition of the photosensitive layer due to the uneven migration of components. Even the use of polyamide subbing layers on these types of higher speed photopolymerizable compositions (as shown in U.S. Pat. No. 4,482,625, Example 4) does not solve this migration problem.
SUMMARY OF THE INVENTION
The use of a substantially aliphatic film-forming polymer comprising a polyurea or polybiuret, generally formed as the reaction product of an amine and a diisocyanate, has been found to provide a good substrate for photosensitive imaging layers. In particular, this film-forming polymer provides good adherence to photopolymerizable compositions, good adherence to polymerized photopolymerizable layers, consistent removal of unexposed photopolymerizable compositions in development solutions and yet provides an easy and clean release for the polymerized composition to a receptor layer when needed.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to photosensitive imaging layers on subbed support layers. The photosensitive compositions are preferably photohardenable compositions and photopolymerizable compositions, although photodepolymerizable compositions and photosolubilizable compositions may also be used. The photopolymerization of the composition should enable differential swellability, dispersability, or solubility in developer solutions between the exposed and unexposed areas. The developer solutions could be water, aqueous, aqueous alkaline, aqueous/organic, or organic. Various polymerizable functions could be used in the photopolymerizable layer such as acryloyl, methacryloyl, epoxy, vinyl, vinyl ether, silane, etc., although acryloyl and methacryloyl functionality is preferred. Preferably the photopolymerizable composition comprises at least 20 percent by weight of monomeric components (i.e., polymerizable compounds having at least two polymerizable moieties) and molecular weights below 1500. These preferred photopolymerizable compositions also comprise less than 50% by weight of inert (non-polymerizable) film-forming binder and 0 to 65% by weight of photopolymerizable oligomers.
The subbing layer of the present invention is generally described as a polyurea or polybiuret, the reaction products of a polyamine and a polyisocyanate. This reaction product tends to be a polyurea. Other chemical reactions occur also, so that the polymerization product need not only be a polyurea. After the reaction of one isocyanate group with a hydrogen of a primary amine, another active hydrogen remains on the reacted amine group. This second hydrogen can, and sometimes will, react with additional isocyanate groups to form a biuret group. This can favorably add to the crosslink density of the subbing layer. In fact, useful subbing layers according to the present invention can be formed from primary aliphatic monoamines and polyisocyanates in forming a polybiuret layer. Generally, however, it is preferred to have both urea and biuret linkages in the polymer of the subbing layer. At least twenty or thirty molar percent of the bridging group in the polymer should be selected from the group consisting of biuret and urea bridging groups. As later noted, other reactions can take place during polymerization such as polysiloxane linking and polyurethane linking. But it is essential to the present invention that some biuret and urea linkages be formed.
Polyureas may be formed by other reaction mechanisms. For example, a polyurea may be synthesized by the addition of polyisocyanate and water. This forms an adduct between the water and isocyanate which can then undergo decarboxylation to form an amine. This amine can then react with additional isocyanate to form the polyurea.
The preferred subbing layer of the present invention comprises a film-forming polymer which is the reaction product of a polyisocyanate (at least diisocyanate) and a polyamine (at least a diamine) wherein the polymer is substantially aliphatic. As used in the practice of the present invention, the term "substantially aliphatic" means that on a molar basis for all bridging groups in the diisocyanates and the diamines, fewer than twenty-five molar percent of those bridging units are aromatic or contain aromatic moieties. Preferably fewer than 20 molar percent, more preferably fewer than 10%, and most preferably fewer than 5% (down to 0%) of such bridging units contain aromatic groups. Preferred amines have the general formula
A.sub.a R(A.sub.b.sup.1 R.sup.1).sub.c --Y
A and A 1 independently represent primary or secondary amines,
R is an aliphatic group
R 1 is an aliphatic group
a is the number of A groups attached to R and is equal to 0, 1 or 2 (preferably 0 or 1)
b is the number of A 1 groups attached to each R 1 group and is zero or a whole integer,
c is the number of A 1 R 1 groups in the compound,
Y is any terminating or functional group, and the sum of a plus bc is at least 2.
By a terminating group it is meant a group without significant reactive or functional properties such as H, lower aliphatic group such as alkyl (C 1 -C 40 ). By functional group is meant a group which can provide particularly desired reactive or functional properties to the final polymer. An example would be --Si(OCH 3 ) 3 (a silane), an oxirane group, an amine group, etc. The sum of a and b is preferably at least three, a preferred range is 2 to 12, more preferred is 3 to 10, and most preferred is 3 to 6.
The preferred polyisocyanates have the formula OCN(CH.sub.2).sub.m D(CH.sub.2).sub.n NCO
wherein n and m are independently 0 or integers, (e.g., 1, 2, 3, 10, 40, 60, etc.), and D is a bridging group, including but not limited to carbon-to-carbon bonds, methine, polymethine (e.g., (CH 2 ) n , cyclopentyl, cyclohexyl, aliphatic (including branched), etc. The bridging group D may also bear isocyanate groups so that polyisocyanates of 2-6 isocyanate groups are contemplated within the scope of the present invention. Preferably aliphatic diisocyanates having 6 to 30 carbon atoms between the isocyanate groups are used. More preferably diisocyanates having 10 to 24 carbon atoms between the isocyanate groups are used.
In order to achieve the most outstanding benefits of the practice of the present invention, not only must the chemical nature requirements of the subbing layer be met, but the physical properties of the layer should be controlled. Those polyureas and biurets formed from the preferred amines and preferred polyisocyanates inherently have those physical properties unless such a high level of deleterious additives are provided which would adversely alter those properties. Other biurets or polyureas, such as those described in U.S. Pat. No. 4,049,746 do not have the desired properties.
The most significant quantitatively measurable property desired for optimum performance in the practice of the present invention is to have reduced surface wettability. The present invention provides a release surface which has low surface energy and is by nature not readily wetted by water. The invention is broadly defined as a substrate which is coated on at least one surface with a substantially aliphatic polyurea (or polybiuret) subbing layer. The maximum utility of this subbing layer as a release surface is realized by formulating the polyurea so as to have a low surface energy. Surface energies of solids can easily be determined by known analytical procedures by measuring contact angles on the surface of solids with liquids. For a detailed description of contact angles, their importance, a means for measuring them, see Adamson, Physical Chemistry of Surfaces, Second Edition, Interscience, 1967, Chapter VII.
Wetting and wettability (W) are usually measured in terms of the contact angle of the liquid on a solid surface. For water wettability
W=0 degrees means complete wetting out,
0 degrees<W<90 degrees=incomplete wetting out, and
90 degrees<W<180 degrees=non-wetting.
It has been found in the practice of the present invention that contact angles with water must exceed 60° , preferrably should exceed 70° , and more preferably exceed 80° . It has also been found that excessive addition of hydrophilic polymer additives or particulate fillers in the polyurea layer can cause the contact angle of pure water to be less than 60° degrees and will be excessively detrimental to the desired surface properties. Examples of such undesirable polymers are polyacrylic acids, polyacrylamide, and sulfonated polystyrene. Examples of undesirable fillers include certain silicas and clays. Often as little as five percent of the coating mass may cause the surface properties to be modified, although such quantities are difficult to predict.
The subbing layer may contain additional ingredients and other reaction products besides the product of the polyamine and the polyisocyanate. For example, additional proportions of binders such as ethylcellulose (to provide good slip coatings) will react with the diisocyanate. Fumed silica may also be added to control the slip properties of the film. The use of silane terminated amines will even react with silica particles to further bind the system together.
Preferred photopolymerizable compositions useful with the subbing layers of the present invention may be described as follows.
The compositions comprise 10-60% by weight of polyfunctional monomers, 10-60% by weight of polyfunctional polymers or oligomers, 0-60% or 10-60% by weight of a polymer which is not polymerizable in the polymerization process of the monomers and oligomers, and 0.1 to 12% by weight of a photoinitiator system. Additionally, the coatings may contain from 2 to 50% by weight of colored dyes or pigments (e.g., cyan, magenta, yellow or black) to provide a color proofing image.
Monomers
The monomeric component of the present invention comprises a free radical polymerizable compound having at least two ethylenically unsaturated groups, and preferably at least 2 to 4 ethylenically unsaturated groups selected from the groups consisting of acrylate, methylacrylate, vinyl and allyl. Preferred are compounds having multiple acrylate and methacrylate groups, e.g., acrylic esters of low molecular weight polyols, such as trimethylolpropanetriacrylate, pentaerythritol tetraacrylate and triacrylate, etc. Preferably these monomers have a molecular weight of less than 2,000 and more preferably less than 1,000.
Suitable free radical polymerizable monomers useful in the compositions of the invention are well known and listed in many patents, e.g., U.S. Pat. Nos. 3,895,949 and 4,037,021. Preferred monomers are the polyacrylate and polymethacrylate esters of alkanepolyols, e.g., pentaerythritol tetraacrylate, tris(2-acryloxyethyl)isocyanurate, tris(2-methyacryloxyethyl)isocyanurate, 2-acetoxyethyl methacrylate, tetrahydrofurfurylmethacrylate, 1-aza-5-acryloxymethyl-3, 7-dioxabicyclo [3.0.0]octane (ADOZ) bis[4-(2-acryloxyethylphenyl]dimethyl methane, diacetone acrylamide, and acrylamidoethyl methacrylate.
Initiator
The compositions of the present invention must also have a radiation sensitive system capable of initiating free radical polymerization upon absorption of radiation. Free radical initators are materials known in the art, such as Free-Radical Chemistry, D. C. Nonhebel and J. C. Walton, University Press (1974). Particularly suitable free radical generators can be selected from many classes of organic compounds including, for example, organic peroxides, azo compounds, aromatic diazonium salts, aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, quinones, benzophenones, nitroso compounds, acyl halides, aryl halides, hydrazones, mercapto compounds, pyrylium compounds, triarylimidazoles, biimidazoles, chloroalkyltriazines, etc. These materials, in general, must have photosensitizers therewith to form a photoinitiator system. Photosensitizers are well known in the art.
Additional reference in the art to free radical photoinitiator systems for ethylenically unsaturated compounds are included in U.S. Pat. No. 3,887,450 (e.g., column 4), U.S. Pat. No. 3,895,949 (e.g., column 7), and U.S. Pat. No. 4,043,819. Preferred initiators are the onium salts as disclosed in U.S. Pat. Nos. 3,729,313; 4,058,400; and 4,058,401. Other desirable initiators are biimidazoles (disclosed in U.S. patent application Ser. No. 824,733, filed Aug. 15, 1977) and chloroalkyltriazines as disclosed in U.S. Pat. No. 3,775,113. These references also disclose sensitizers therein. Another good reference to photoinitiator system is Light-Sensitive Systems, J. Kosar, 1965, J. Wiley and Sons, Inc., especially Chapter 5.
Oligomers and Polymers
A reactive polymer is defined in the practice of the present invention as any polymeric material having at least two polymerizable groups thereon and having a molecular weight greater than that of the monomer component. Preferably the molecular weight of the reactive polymer is sufficiently high that it is a film forming polymer by itself. This is generally indicated by a molecular weight of at least 2,000. It is also desirable that the reactive polymer swell in aqueous alkaline developer having a pH of 7.5 or greater. Combinations of reactive polymers are particularly desirable in tailoring the properties of the photosensitive layer. Swellability of one component emphasizes ease of developability in aqueous alkaline solution. Non-swellability of another reactive polymer component will contribute to the cohesiveness of the photosensitive layer during development. By balancing the proportions of swellable and non-swellable reactive polymer, one can provide whatever balance of ease of developability and cohesive strength that is necessary for particular product needs.
The oligomeric or polymeric component of the present invention comprises a free radical polymerizable oligomer having an ethylenically unsaturated group equivalent weight of between 45 and 5000 and being of a higher molecular weight than said monomer. Preferred oligomers are shown in U.S. Pat. No. 4,304,923 as urethane oligomers.
A generic structural formula for the urethane oligomers can be drawn as follows: ##STR1## wherein E is an ethylenically unsaturated, free radical polymerizable group, preferably selected from acryloyloxyalkoxy (alternatively named acryloxyalkoxy), methacryloylalkoxy (alternatively named methacryloxyalkoxy), vinylalkoxy, and allyloxy,
D is the residue of a polyisocyanate (preferably a diisocyanate) having at least two of its --N═C═0 groups reacted to form ##STR2## D bonding E to R, A is a carboxylic acid containing group (e.g., ##STR3## a is a number having an average value between 2 and 20, b is a number having an average value between 0.3 and 10, and m=1 to 6,
R is the residue of a polyol having at least a+b hydroxyl groups and a number of average molecular weight between 90 and 10,000, the residue formed by removal of hydrogen from the hydroxyl groups.
The backbone of the oligomer, group R, may be any aromatic or aliphatic polyol having a molecular weight between 90 and 10,000. The backbone of the oligomer may be any oligomer with the requisite molecular weight and number of hydroxyl groups, but polyesterpolyols and polyoxyalkylene polyols are preferred. Linear oligomeric polyols are useful but the branched or three-dimensional polyols such as polycaprolactone polyols are preferred. The backbone may be prepared by any of the many well known methods of forming polyhydroxyl substituted oligomers having a molecular weight between 90 and 10,000. The polyols must have a hydroxy equivalent weight of between 45 and 5,000 to be useful according to the present invention. Preferably the polyol has a hydroxy equivalent weight between 90 and 4,000 and most preferably between 200 and 2,000.
The oligomers backbone may be homopolymeric, copolymeric, graft polymeric, or mixtures thereof. For example, polycaprolactone polyols may be used, or lower molecular weight polycaprolactone polyols (average molecular weights of less than, for example, 500) may be joined by polyacids (preferably dicarboxylic acids) or by polyisocyanates (preferably diisocyanates) to form higher molecular weight oligomer backbones.
Other useful reactive polymers include the reaction of a styrene-maleic anhydride copolymer and hydroxyethylmethacrylate. acrylate. That reaction is effected by simply heating the two materials in a non-reactive solvent. An example of a particularly useful class of non-swellable reactive binders is acrylate functional cellulose esters. A preferred example of that class is the reaction product of cellulose acetate proprionate and isocyanatoethylmethacrylate.
Binders
The binder component of the present invention comprises an organic, polymeric thermoplastic binder having a molecular weight of at least 1,000 which is preferably not reactive with the polymerization mechanism of the monomer or oligomer. To be non-reactive with the oligomer and monomer, the binder must be able to pass the following test: 5 grams of the candidate binder, 3 grams of pentaerythritol tetraacrylate, 0.4 grams of diphenyliodonium hexafluoroantimonate and 0.4 grams of 4,4'-bis(dimethylamino) benzophenone sensitizing dye are dissolved in organic solvents (e.g., methylethylketone, isopropanol, ethylacetate, n-propanol/water azotrope, and mixtures thereof), and then irradiated for 15 seconds to a carbon arc having a 5,000 watt output at a distance of about 1 meter. If at least 90% by weight of the binder can be separated from the polymerized acrylate by leaching or other differential solvent techniques, the binder is non-reactive according to the teachings of the present invention.
The binders preferably should be heat-softenable between 100° and 400° F. (38° C. to 205° C.). It is also particularly useful to the present invention that the binder not be soluble in at least one solution selected from the class consisting of aqueous alkaline solutions at a pH of 9.0 (e.g., water and NaOH), aqueous alcohol solutions (e.g., water and n-propanol, 80/20 blend), and organic solutions (e.g., toluene/ethyl acetate, 50/50 blend). The inability of the binder to be solubilized by at least one of these solutions assists in preserving desired properties during the development process. If the binder is not solubilizing and leached from the polymerized areas, its desirable thermoplastic properties will be preserved in the polymerized image areas, enable subsequent transfer. The most preferred binders in the practice of the present invention are polyketones. Lower molecular weight acrylates and polyesters are also useful.
The substrates useful with the subbing layers of the present invention include polymeric resins (e.g., polyesters such as polyethyleneterephthalate, cellulose esters such as cellulose triacetate and cellulose acetate proprionate, poly(vinyl acetals) such as poly(vinyl formal), poly(vinyl chloride), poly(vinylidene chloride), polyolefins, etc.), paper (both cellulose fiber and polymeric fiber paper), metallized polymers, polymer coated metals, glass, pigmented paper (i.e., coated printing stock), ceramic, etc. It is preferred in the practice of the present invention to use polymeric film substrates, particularly transparent polymeric film substrates, and most preferably polyester substrates. Additional layers such as antihalation layers may be associated with the substrate as needed or desired.
Other additional ingredients may be present in the subbing layer such as coating aids, surfactants, high molecular weight binders, lubricants, matting agents, antihalation dyes, etc. These and other aspects of the present invention will be further understood from the following nonlimiting examples.
EXAMPLE 1
The following coating composition was made by first dissolving the binder (ethyl cellulose) and then adding the remaining ingredients in the order shown below:
______________________________________ethyl cellulose (N22, Hercules) 40 g1,1,2-trichloroethane 18 kgdodecyldiisocyanate (DDI 1410, Henkel) 180 gpolyamine-silane (A 1130, Union Carbide)* 20 gdibutyltin dilaurate 10 g______________________________________ *structural formula is H.sub.2 N(CH.sub.2).sub.2 NH(CH.sub.2).sub.2 NH(CH.sub.2).sub.3 Si(OCH.sub.3).sub.3
This solution was coated onto unprimed 2 mil (5.08×10 -2 mm) polyethyleneterephthalate film to provide a dry coating weight of 150 mg/m 2 . This dried subbing layer was overcoated with a coating solution comprising:
______________________________________pentaerythritol tetraacrylate 50 goligomer (Preparation II of U.S. Pat. No.4,228,232) 40 gcarbon black 30 gdiphenyl iodonium hexafluorophosphate andsensitizing dye 2 gtrichloroethane 1600 g______________________________________
The dried photosensitive element was contact imaged through a photographic negative and developed in an aqueous alkaline solution containing 1.5% by weight sodium hydroxide and 0.2% of a normal phenol ethylene oxide adduct, a non-ionic surfactant wetting agent (marketed as X-100 by Rohm and Haas) and then air dried. The image developed with good resolution and, after drying, transferred to a resin coated paper receptor sheet in a hot two roll laminator. The peel force required to remove the laminated film from the paper was very low. The subbing layer remained with the polyester film.
A comparison of the film of this invention was made by using a subbing layer coating solution of
______________________________________Elvamide 8063 (alcohol soluble polyamidedescribed in U.K. 1,441,982 and U.S.Pat. No. 4,482,625) 50 gMethanol 1000 gTrichloroethane 1000 g______________________________________
Coatings were made at coating weights varying from 10 mg to 300 mg/m 2 , coated with the photosensitive composition of this Example 1, then exposed and developed as in this Example.
The lower coating weights (less than 50 mg/m 2 ) of the Elvamide provided good bonding of the photopolymer image, but failed to provide release in the thermal transfer step. Higher coating weights caused substantial loss of the photopolymer photographic speed due to the swelling of the polyamide by the monomer.
Comparisons with coatings of polyacrylates, cellulose polymers, vinyl acetates, polyvinyl alcohol, polyvinyl butyral, chlorinated polymers, polyvinyl ethers (and copolymers thereof), fluoropolymers, polysiloxanes, gelatin, polyethylene (and copolymers), polyurethanes (polycarbonates), and unsaturated hydrocarbon polymers (e.g., polybutadiene) were made. Failure of each of these materials fall into two distinct types. In one group (polyamides, polyurethanes, polyesters, etc), thermal release was very poor. In the second group, the developer had difficulty in differentiating between exposed and unexposed areas so that photopolymerized images could be lifted from the support (subbing layer) by the developer action.
When 100% of the aliphatic diisocyanate used in Example 1 was replaced with an aromatic diisocyanate
OCN--C.sub.6 H.sub.4 --CH.sub.2 --C.sub.6 H.sub.4 --NCO
and the remainder of the Example repeated, poor thermal release properties were obtained.
The same results occurred when the aliphatic amine of Example 1 was replaced with m-xylylenediamine, C 6 H 4 (CH 2 NH 2 ) 2 . Poor thermal release properties were obtained.
EXAMPLE 2
Example 1 was repeaeed except that the aliphatic amine-silane was replaced by triethylene tetraamine on an equivalent weight basis. Essential identical high quality results were obtained as found in Example 1. The silane moiety of Example 1 tends to have the effect of increasing solvent resistance during overcoating. That moiety is desirable, but not essential to the present invention.
EXAMPLE 3
Example 1 was repeated except that the dodecyldiisocyanate was replaced with 80 grams of 1,6-diisocyanato hexane. Care was taken to keep the diisocyanate from evaporating before polymerization. The coating worked well as a subbing material for the polymerizable composition. | Subbing layers on carrier elements for use with photopolymerizable, photosolubilizable, and photodepolymerizable compositions are advantageously comprised of polyureas and polybiuret polymer. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a sheet or web-like medium dispensing apparatus, and more particularly, to a dispenser which is designed to dispense, one by one, a stack of media, in the form of a lamina or web, such as reproduction paper or the like in a suitable size and then separate the medium from the media, feed them to the next work station.
2. Prior Art
A dispenser for separating and feeding, one by one, a stack of sheet or web-like media such as reproduction paper, printing paper, and a blank sheet of paper, lamina or web has been widely used in various types of industrial equipments and apparatus such as an enveloping and sealing machine, a reproducing machine, a facsimile transmitter and receiver unit, a printing press, a converter machine for paper or the like, and an office automation instrument and the like.
A dispensing apparatus of this class as aforementioned comprises, as shown in the accompanying drawings, FIG. 3, a stacker table 1 so disposed as to incline its forward end downwardly, a stopper 2 against which a stack of media 3 on the stacker table, a pair of friction rollers 7, 8 of rubber or the like, and openings 5, 6 formed in the table 1 to have a portion of each of the friction rollers extended and passed therefrom and therethrough whereby only lowermost medium 4 is dispensed and fed to the next work station by timing and operating the rollers to provide frictional rotation thereof.
The foregoing apparatus is defective in that media are stacked to each other without any clearance therebetween and are thus subject to resistance against surface friction thereof, resulting in considerable resistance. For this reason, rotational force of the rollers could not resist frictional resistance of the media to provide slippage on the rollers. Thus crumpling, jamming the media and occasionally resulting in damage thereto, how much more the media with rugged surface do. This will prevent the apparatus from repeating the same operation.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an apparatus which is capable of dispensing of media in the form of a sheet or web, lamina or the like so as to separate and feed the latter to the next station.
Another object of the invention is to provide a sheet-like medium dispensing apparatus which enables the media to reduce frictional resistance therebetween.
A further object of the invention is to provide a web or lamina-like medium manipulating and dispensing apparatus which fully eliminates defects or disadvantages such as a slip or slippage of the rollers.
Still another object of the invention to provide a web or lamina-like medium manipulating apparatus which is capable of ensuring prevention of jamming or clogging of the media to positively feed, one by one, the media downstream of the roller(s).
These and other objects of the invention are accomplished by the combination and function of the rollers disposed upstream and downstream of a stacker table which is provided with a recess formed therein.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the invention will become apparent from the following descriptions taken in conjunction with the attached drawings in which:
FIG. 1 is a schematic sectional view of a paper sheet material handling device according to a first embodiment of the invention;
FIG. 2 is a schematic sectional view of a paper sheet material handling device according to a second embodiment of the invention; and
FIG. 3 is a schematic sectional view of a prior art paper sheet material handling device.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows a first embodiment of the present invention, in which, a stack of media 10 are stacked on a stacker table 12 with the downstream side (left side in the drawing) being inclined downward. The front or forward edge of the media 10 is retained by a stopper 14.
A pair of openings 16 and 18 are formed in the stacker table 12 to extend along the entire width of the table 12 preferably. A recess 20 is formed in the upper surface of the table 12 and between the grooves 16 and 18. In respective openings 16 and 18, there are provided rotatable friction rollers 22 and 24 (a dispenser roller 22 and a separator roller 24) respectively portions of which project slightly upward from the upper surface of the stacker table 12. The friction rollers 22 and 24 are formed to have surfaces having a high frictional coefficient by being provided with an outer surface made of rubber or the like. The depth of the recess 20 is nearly equal to the diameter of the rollers 22 and 24. In the upstream side (the right side in FIG. 1) of the opening 16, another opening 26 is provided in the stacker table 12. A roller 28 having a generally square shaped cross-section is rotatably mounted in the groove 26. The roller 28 is disposed such that one of the corner portions of the roller 28 projects upward from the upper surface of the stacker table 12 when the roller 28 rotates, whereby when the roller 28 rotates the corner portions of the roller 28 contact sequentially with the media 10 supported on the stacker table 12 thereby vibrating the media 10 in a vertical direction. The roller 28 is preferably formed of a resin or the like having a relatively low frictional coefficient. The roller 28 need not necessarily be formed to have a square cross-section, and may be in the form of a triangle, a pentagon, a hexagon, or any suitable shape having a suitable number of cornered portions on the outer circumference. Thus, the roller 28 is referred to as a square rotator. The friction roller 22 and the square rotator 28 are rotated in synchronized relationship in the direction of the arrow 32 by a motor 30 mounted on a frame of the device and through motion transmitting means such as a belt known per se.
Similarly, the friction roller 24 is driven by another motor 34 which is also mounted on the frame and through a motion transmitting means such as a belt known per se.
In the embodiment, when it is desired to deliver the lowermost medium 38 of the media 10, the motor 30 is actuated with the motor 34 not being actuated. Then, the square rotator 28 is rotated by the motor 30 thereby imparting vibrations acting in a vertical direction to the media 10. The frequency of the vibrations is suitably adjusted to correspond to the amount or weight of the media 10 on the stacker table 12 and the surface condition of the paper sheets constituting the media 10. By increasing the rotational speed of the motor 30, it is possible to improve separating characteristics, but it will be noted that the rotational speed of the motor 30 should be determined with consideration to the size and shape of the square rotator 28 and the surface condition of the stacked sheets. Owing to the vibrations of the square rotator 28 there is formed a slight clearance between respective paper sheets in the media 10 being mounted on the stacker table 12.
The friction roller 22 is also rotated when the square rotator 28 is rotated. But the friction roller 24 is not rotated in this condition, thus the forward end (the left end in FIG. 1) of the lowermost medium 38 is maintained at a standstill condition by the friction roller 24.
By rotation of the friction roller 22 in contact with the lowermost medium 38, the latter is fed in such a manner that its mid-portion is forwardly moved to thus treat the medium 38. Consequently, the medium 38 is moved and enters into the recess 20 in the stacker table 12, as shown.
When the lowermost medium 38 is moved forward by the friction roller 22 such that the sheet medium 38 contacts with nearly the entire surface of the recess 20 in the stacker table 12, the motor 34 is actuated. The friction roller 24 rotates and the lowermost medium 38 of the media 10 now separated from the remaining stack of sheets is separated from the media 10 and is delivered downstream through a gap between the upper surface of the stacker table 12 and the lower edge of the stopper 14.
According to the embodiment, the mutually contacting area between the lowermost medium 38 and the remaining stack of sheets in the neighborhood of the friction roller 24 is reduced to a minimum. As compared with the prior art device shown in FIG. 3, in which the lowermost medium contacts along the entire surface of an adjacent sheet, the sheet medium 38 according to the present invention can be easily delivered from the media 10 with only a small contacting resistance, thereby solving the problem of slippage and the like.
FIG. 2 shows another embodiment of the present invention. According to the embodiment of FIG. 1, in moving a portion of the lowermost medium 38 into the recess 20 of the stacker table 12, if the amount of the movement of the lowermost medium 38 into the recess 20 is not sufficient, the friction roller 24 may slip and the amount of the delivery of the sheet medium 38 may become insufficient. The device of FIG. 2 aims to solve this problem.
Reference is now made to FIG. 2, which is generally similar to FIG. 1 with corresponding parts being denoted by the same reference numerals. As shown in FIG. 2, there is provided detection means such as a micro-switch 40 in the recess 20 in the stacker table 12 so as to adjust automatically the timing of actuation of the friction roller 24. A lever 42 of the micro-switch 40 projects upward from the upper surface of the recess 20 in the stacker table 12. Further, for delivering the paper sheet material reliably one sheet at a time, there is provided another friction roller 25 on the downstream of the friction roller 24. The friction rollers 24 and 25 are driven synchronously by a motor 34. A generally L-shaped separating member 44 is provided upward of the friction roller 25 and is biased toward the friction roller 25 by a means such as spring. A sensor 46 is provided on the downstream side of the friction roller 25 to detect the presence of a paper sheet material.
In delivering the lowermost medium 38 of the media 10 which is stacked on the stacker table 12 according to the embodiment of FIG. 2, the motor 30 is actuated firstly with the motor 34 being maintained at a stopper position. The square rotator 28 is rotated by the motor 30 and the media 10 on the stacker table 12 is vibrated in a vertical direction. The frequency of the vibrations or the speed of the motor 30 is determined suitably in considering the amount or the weight of the paper sheet material stacked on the stacker table 12, the surface condition of the paper sheet material and the like. According to the vibrations afforded by the square rotator 28, some clearance may be formed between the paper sheet materials consisting the media 10 on the stacker table 12.
In synchronizing with the rotation of the square rotator 28, the friction roller 22 rotates in a counter clockwise direction as shown in the drawing. Preferably, a one way clutch (not shown in the drawing) is provided to permit free rotation of the roller 22 in the same counter clockwise direction. At this time, the rollers 24 and 25 are maintained in a stopper condition since the motor 34 is not actuated, thus, the forward edge of the lowermost medium 38 of the media 10 is maintained at a standstill by the friction roller 24.
By rotation of the friction roller 22, the intermediate portion of the lowermost medium 38 contacting with the roller 22 is displaced forward, thus being separated from the remaining sheet of the media 10. Thus, a portion of the sheet medium 38 is delivered into the recess 20 in the stacker table 12 as shown in the drawing.
When a portion of the sheet medium 38 is delivered into the recess 20 in the stacker table 12 as shown in the drawing, the lever 42 is pushed by the sheet medium 38 in the direction of the arrow 48 as shown in the drawing, and actuates the micro-switch 40.
When the micro-switch 40 is made to ON, the motor 30 is stoppered and the another motor 34 is actuated to rotate the friction rollers 24 and 25 in the direction of the arrow 36. The paper sheet medium 38 now separated from the media 10 is displaced downstream through a space between the lower end of the stopper 14 and the stacker table 12. When the sheet medium 38 of curved condition is displaced downstream by the friction rollers 24 and 25, the lever 42 moves in the direction opposite to the arrow 48 which puts the microswitch 40 into an OFF position.
When the micro-switch 40 is positioned to be OFF, the motor 34 stops rotating and the motor 30 starts rotating again. The friction roller 22 acts once more as a separating roller to introduce a portion of the lowermost medium 38 of the media into the recess 20 in the stacker table 12. Then, the micro-switch 40 is actuated to stops the actuation of the friction roller 22 and to start the delivery rollers 24 and 25, thereby the paper sheet medium 38 is displaced downstream.
Such an operation is repeated until the light directed into the sensor 46 is intercepted by the front end of the paper sheet medium 38 being delivered. When the light entering the sensor 46 is intercepted, the motor 34 is rotated whereby the friction rollers 24 and 25 are caused to rotate to fully displace the sheet medium 38 to downstream.
When the paper sheet medium 38 has passed through the sensor 46 completely, the device returns to its initial state, and the operation is repeated.
In the embodiment, the separating plate 44 acts such that when two or more sheets are delivered together, the plate 44 intercepts the delivery of the upper sheet and stoppers it at that position and when the sheet of lower side is fully delivered the delivery of the upper sheet is permitted. Thus, sheets are reliably delivered one at a time. Incidentally, the micro-switch 40 is utilized as a detection means, however, the invention is not limited to the embodiment and, any suitable detecting means such as a combination of an intercepting plate projecting on the recess 20 of the stacker table 12 and a photo-interrupter acting in response to the intercepting plate, and the like.
In the embodiment of FIG. 2, similar to the embodiment of FIG. 1, the friction roller 24 acting to separate the paper sheet material enables a substantial reduction in an area of contact between paper sheet materials. Particularly, as shown in FIG. 2, the sheet medium 38 is flexed downward as compared with the prior art shown in FIG. 3, thus, resistance caused by mutual contact is substantially reduced and the sheet medium 38 can easily be delivered, which solves the problem of the slippage of friction rollers. Further, the embodiment of FIG. 2 enables the rotation of the paper sheet material delivering rollers to be stoppered automatically in response to the amount of flexure of the paper sheet material into the recess 20 in the stacker table 12.
As described heretofore, according to the invention, it is possible to effect separation of the paper sheet material and to prevent jamming of the paper sheet material reliably, and to supply reliably a paper sheet material one sheet at a times to the downstream. | An apparatus for dispensing, one by one, a stack of media as stacked in a stacker table by friction rollers to separate and supply the media to the next work station. The friction rollers are rotated in such a manner that rotational force thereof is provided to overcome any frictional resistance generated between the media so that no slip is caused between the rollers to obtain a smooth medium without damage thereto. | 1 |
BACKGROUND OF THE INVENTION
Certain products are suitable for being boxed and transported for further treatment. For example, some varieties of berries may be collected in large containers before they are cleaned, sorted and packaged for retail sale. The containers used in such operations are sometimes very large, occupying space which could be better utilized if the boxes could be folded and stacked during storage. In answering this need, collapsible containers have been designed such as were disclosed in U.S. Pat. No. 5,484,380. These collapsible containers are often very heavy and considerable manual labor is required to re-assemble them.
This invention relates to an improved method for handling collapsible containers of the type described in U.S. Pat. No. 5,484,380. More specifically, it involves a device and method to re-assemble collapsed collapsible topless containers which are designed to be broken down for stacking, storing, and transporting. The method consists of unfolding the collapsed container by lifting it by one of its sides and depositing the unfolded container onto a pallet, which releasibly engages two opposing side walls.
SUMMARY OF THE INVENTION
The object of the present invention is a non-manual system for manipulating collapsed collapsible topless wooden containers of the type having four sides pivotal to each other and a base. Adjacent sides of the container are hinged together by means of two or more flexible straps. In an assembled container the sides are releasably attached to the base by means of at least two sets of U-shaped clips on two opposing side walls of the container. Specifically, the system re-assembles the collapsed collapsible topless containers by unfolding the collapsed sides and placing the unfolded sides onto the base.
The system consists of an elevator-transfer sub-unit and an assembler sub-unit which act cooperatively. The elevator-transfer sub-unit has an upright element which is attached to a base element, a roller-slide device which is capable of moving up and down the upright element and a means to move the roller slide up and down. A horizontal suspension arm which is fixedly attached to the roller slide extends laterally and towards the assembler sub-unit. An inverted T-rail is pivotally attached to the suspension arm. An air driven piston/cylinder-device which connects to the T-rail and suspension arm pivots the T-rail. A trolley with at least one set of wheels runs along the T-rail. A first grasper is pivotally attached to and suspended from the trolley. The first grasper has a means to engage one side of a collapsed collapsible container releaseably.
The assembler sub-unit comprises a base member and an upright member. A horizontal arm is fixedly attached to and extends laterally from the upright member. It is directed towards the suspension arm of the elevator-transfer sub-unit. A second grasper is pivotally attached to the distal end of the horizontal arm and is capable of receiving the ends of two opposing sides of an unfolded collapsible. The second grasper engages the container, rotates 90 such it such that it is in an upright position over a base. When a container is positioned over a base, the container is released and it falls unto the base to which it is releaseably attached by U-clips. The cycle can be repeated by leaving the first grasper over a collapsed container.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 . Schematic side view of the apparatus that is the subject of this invention.
FIG. 2 . Top perspective view of the first grasper of the invention.
FIG. 3 . Perspective view of the location of the second grasper of the invention.
FIG. 4 . Broken away view of the camming device located on the bottom side of the first grasper.
FIG. 5. A side view of the second grasper of the invention.
FIG. 6 . Partial broken away view of the second grasper of the invention.
FIG. 7. A schematic side view of the trolley of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 the container assembling system of this invention has an elevator/transfer sub-unit 10 and a container assembling sub-unit 110 which interact cooperatively, and a controller unit, a power source and a compressed air source, all of which is known in the art (not shown). The elevator/transfer sub-unit 10 and the container assembling sub-unit 110 each have a base 11 & 111 and upright columnar members 12 & 112 which are of I-bar construction. The subunits 10 & 110 are connected by an upper crossbeam 110 which connect the upright columnar members 12 & 112 and a lower base beam 115 which joins the bases 11 & 111 . A catwalk (not shown) may ride on the upper crossbeam 111 .
The elevator/transfer sub-unit 10 has a roller slide device 14 which is known in the art and which is capable of moving up and down the first upright columnar member 12 . A first pulley 31 is attached to the lower portion of the first upright columnar member 12 .
A power driven motor 28 with a shaft 33 is fixedly attached to the first columnar member 12 . A motor pulley 31 a is located on the shaft. A driver chain 30 is attached by both ends to the roller slide device 14 and is suspended between motor pulley 31 a and the lower pulley 31 . The power driven motor 28 is connected to and controlled by a controller (not shown). A horizontal balance beam 16 is fixedly attached to the top of the first upright columnar member 12 . The horizontal balance beam 16 has first 17 a and second 17 b ends. Second pulleys 18 a and 18 b are attached to the first and second ends 17 a and 17 b of the balance beam 16 .
The roller slide device 14 has a triangular suspension arm 20 which is made of metal box tubing. The arm 20 extends laterally towards the container assembling sub-unit 110 . A cable 26 which is suspended from the second pulleys 17 a & 17 b connects the triangular suspension counterweight 24 . An upright guide 33 which runs parallel to the first upright columnar member 12 is attached between the balance beam 16 and base 11 . They pass through apertures 25 b in the counterweight 24 as shown in FIG. 1 .
A first contract switch 34 which is capable of engaging the roller slide 14 is attached near the top of the upright columnar member 12 . The first contact switch 34 is connected to the controller unit (not shown). A sensor 51 capable of being activated by contact is located on the distal end of the triangular suspension arm 20 .
A trolley/rail system 40 , which is a rectangular structure consisting of an upper bar 42 and a lower inverted T-rail 44 and connecting members 43 , is pivotally attached to the suspension arm 20 as shown in FIG. 1 . The inverted T-rail 44 may be box tubing. A first air driven piston/cylinder device 48 is fixedly attached to the upper bar 42 . The piston rod 49 of the device 48 is connected to the upper bar 42 . Trolley stop members 52 a & 52 b are fixedly attached to each end of the T-rail 44 . Guide rods 55 run on each side of the T-rail 44 , extending between the stops 52 a, 52 b. A spiral spring member 54 , which is capable of cushioning a trolley 70 upon impact, is located distally to the proximal trolley stop member 38 around the guide rod 54 .
A first brake mechanism 56 is attached to the distal half of the trolley/rail system 40 . The brake mechanism 56 is of angle iron construction whose proximal end 57 is pivotally attached to the upper bar 42 . Its distal end 58 is attached via a biased air cylinder/piston mechanism 60 , which is known in the art, to the upper bar 42 . In the preferred embodiment a second brake mechanism 57 is attached to the trolley/rail system 40 to provide braking proximally. It is attached in a manner that is a mirror image of the first brake mechanism 56 .
A trolley 70 with at least one pair of wheels 72 is suspended on the T-rail 44 . The trolley 70 has a plate member 74 extending upwardly sufficiently to engage the brake mechanisms 56 & 57 . Referring to FIG. 7, a teflon block 76 is embedded in the top of the plate member 74 and is capable of engaging the brake mechanisms 56 & 57 . Referring to FIG. 1 a roller 5 is supported by two roller supports 6 which are attached to and extend upwardly from the first base 11 and acts to keep a container 100 which is suspended from the first grasper 80 from swaying. It is located off-center sufficiently to accommodate the container and is oriented parallel to the lower base beam 115 .
A first grasper 80 is pivotally attached to the trolley 70 by a connecting member 71 . Referring to FIG. 2 the first grasper 80 is a rectangular frame structure with two long sides 84 and two short sides 86 Which support two crossbeams 88 and a central beam 89 . The central beam 89 is fixedly attached to the connecting member 71 as shown in FIG. 2 . Third air driven cylinder/piston members 92 are attached to the upper sides of the crossbeams 88 .
Referring to FIG. 4 camming devices 94 , which are sets of four wheels 95 arranged in series, are attached to the crossbeams 88 by shafts 96 which extend through the crossbeams 88 . The second wheel 95 is attached to the piston of the third air driven piston/cylinder members 92 . The second and third wheels 95 , which are cogged, of the camming devices 94 interact with each other by cogs 96 . The first and fourth wheels 95 are connected to the second and third wheels 95 , respectively, by metal plates 97 . The first and fourth wheels 95 are connected to second cams 98 on the underside of the cross beams 88 as shown in FIG. 3 by their shafts 96 . The second cams 98 are shown in both engaging 98 and disengaging 98 a positions with respect to a side of a collapsed container in FIG. 3 .
The cam faces 99 of the second cams 98 have convexedly curved configurations adapted to engage with upwardly directed slats 103 of the collapsible container 100 . The leading surfaces 101 of the cam faces 99 have a greater radius than the trailing surfaces 102 . Referring to FIG. 3 a contact switch 91 , including a switch actuator, which is known in the art, moveable between open and closed positions is located on the underside of the central beam 89 .
Referring to FIG. 1 sub-unit 110 consists of a second upright columnar member 112 on a base 111 . The second upright columnar member 112 supports an arm 114 which extends horizontally towards the first grasper 80 . A second grasper 116 is pivotally attached to the distal end of the arm 114 by a second camming device 130 . The camming device 130 is attached by a chain 113 to a fourth air driven piston/cylinder assembly 115 which is fixed attached to second upright columnar number 112 .
The second grasper 116 is shown in FIG. 5 and 6. It has a grasper shaft 120 which supports two short support bars 122 which are suitably spaced parallel to each other. The short 122 support bars support two longitudinal frame member 124 that extend beyond the points of attachment to the short support bars 122 . The short support bars 124 are fixedly attached to the two longitudinal frame members 124 . The longitudinal frame members 124 support a pair of spaced channels 126 , each channel 126 being for by a fixed flange 128 . The spaced channels 126 are capable of receiving opposing sides 101 of the uncollapsed collapsible container 100 . The moveable flange 129 is attached by a fifth air driven piston/cylinder device 132 at grasper end plate 134 . Lateral guide plates 136 are fixedly attached to the ends of the fixed flange 128 and grasper and plates 134 . The spaced channels 126 are sufficiently wide to receive the ends of side walls 101 of a collapsible container 100 . The fifth piston/cylinder device 132 is connected to and controlled by a controller unit (not shown) which is known in the art. A contact switch 138 is located in one spaced channel 126 and connected to the controller unit (not shown). It is actuated by contact with a side wall 101 of container 100 .
A pair of compressing piston/cylinder devices 200 a & 200 b are located on the lower base beam 115 . The piston head 201 is tapered inwardly and downwardly so as to push the two sides 101 of the container 100 inwardly. They are spaced to receive an unfolded collapsible container 100 .
In the operation of the container assembling system, when the machine is turned on, the driver motor 28 drives the driver chain 30 to lower the roller slide 14 . This causes the first grasper 80 to come in contact with a collapsed container 100 . Contact switch 91 is activated by contact with the container 100 . This activates the third piston/cylinder member 92 to cause the cam device 94 to be activated thereby causing the cam faces 99 to engage container 100 by its slots 103 . After a delay relay to the driven motor 28 , it is activated to move the driven chain 30 and raise the roller slide 14 .
When the switch 91 is activated air enters the piston/cylinder member 92 , thereby moving the wheels of camming device 94 causing them to rotate. The rotation of the cam causes interconnected wheels to rotate thereby causing the camming faces 99 of second cam members 98 to engage opposing sides of adjacent slats 103 of a collapsed collapsible container 100 .
When the collapsed collapsible container 100 is fully engaged by the second cams 78 the power driven motor 28 is activated as a result of time delay relay which is known in the art. This causes the driver chain 30 to lift the roller slide 14 . As the roller slide 14 moves upwardly the collapsed container 100 unfolds. At the top of the lifting cycle the roller slide 14 engages contact switch 34 . Upon contact the switch is activated causing the power to the driven motor 28 to be turned off and causing first piston/cylinder device 48 to lift the trolley/rail system. The force of gravity causes the trolley to move to the distal end of the T-rail 44 causing the container 100 to engage a second grasper 116 of sub-unit 110 . Specifically, the ends of the side walls 101 enter the spaced channels 126 .
The contact switch 138 is activated thereby causing the fifth air driven piston/cylinder devices 132 to move the movable flange 129 toward to engage the container 100 which lies in the spaced channels 126 . After a suitable time delay by means known in the art the fourth air driven piston/cylinder assembly 115 is activated to allow the second grasper 110 with container 100 to rotate 90 degrees whereby a third contact switch 137 is engaged. This activates the fifth piston/cylinder devices 132 to move the moveable flange 129 back thereby releasing the container 100 , allowing it to fall onto the pallet base 105 . Two opposing sides 102 engage the compressing pistons/cylinder devices 200 a and b causing the sides to move inwardly, allowing the U-clip (not shown) of the container 100 to engage the pallet base 105 , when the pressure is released after a time delay. The second grasper 116 , after a time delay rotates 90° to its resting position by action of the fourth air driven piston/cylinder device 115 . This disengages third contact switch 137 . At the same time the driver motor 28 is activated to lower the roller slide 14 (the start of a new cycle). | A system for re-assembling collapsed collapsible topless containers which have four side walls pivotal to each other and a pallet. The system unfolds a collapsed container by lifting it up by one of the sides. The unfolded container is transferred to an assembling sub-unit which tips the unfolded container upright and deposits it on the pallet which releasably engages two opposing side walls. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of International Patent Application No. PCT/CN2014/000285 with an international filing date of Mar. 17, 2014, designating the United States, now pending, and further claims priority benefits to Chinese Patent Application No. 201410079508.5 filed Mar. 6, 2014. The contents of all of the aforementioned applications, including any intervening amendments thereto, are incorporated herein by reference. Inquiries from the public to applicants or assignees concerning this document or the related applications should be directed to: Matthias Scholl P.C., Attn.: Dr. Matthias Scholl Esq., 245 First Street, 18th Floor, Cambridge, Mass. 02142.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The invention relates to a DNA polymerase possessing continuous catalytic capacity and salt tolerance.
[0004] Description of the Related Art
[0005] The DNA polymerase used in the recombinase-mediated isothermal nucleic acid amplification belongs to the DNA polymerase I family. However, the DNA polymerase I family often has relatively low continuous catalytic capacity, which means that the polymerization reactions catalyzed by each binding between the polymerase and a template have low efficiency.
SUMMARY OF THE INVENTION
[0006] In view of the above-described problem, it is one objective of the invention to provide a DNA polymerase possessing continuous catalytic capacity and salt tolerance, which is a hybrid DNA polymerase prepared by inserting a thioredoxin binding domain (TBD) of bacteriophage T7 DNA polymerase into a DNA polymerase I (Sau) of S. aureus , so as to overcome the relatively low continuous catalytic capacity of the DNA polymerases of the DNA polymerase I family.
[0007] It is another objective of the invention to provide a gene encoding the DNA polymerase possessing continuous catalytic capacity and salt tolerance.
[0008] It is still another objective of the invention to provide a method for preparing the DNA polymerase possessing continuous catalytic capacity and salt tolerance.
[0009] It is still another objective of the invention to provide a method for using the DNA polymerase possessing continuous catalytic capacity and salt tolerance.
[0010] To achieve the above objective, in accordance with one embodiment of the invention, there is provided a DNA polymerase possessing continuous catalytic capacity and salt tolerance, being a hybrid DNA polymerase prepared by inserting a thioredoxin binding domain (TBD) of bacteriophage T7 DNA polymerase into a DNA polymerase I (Sau) of S. aureus , having an amino acid sequence represented by SEQ ID No. 2 or an amino acid sequence of similar functions by substitution, deletion, or addition of at least one amino acid residue.
[0011] In accordance with another embodiment of the invention, there is provided a gene encoding the DNA polymerase possessing continuous catalytic capacity and salt tolerance, having a nucleotide sequence represented by SEQ ID No. 1.
[0012] In accordance with still another embodiment of the invention, there is provided a method for preparing the DNA polymerase possessing continuous catalytic capacity and salt tolerance. The method comprises:
1) determining a corresponding position and a target substitution sequence in Sau protein for the TBD of the bacteriophage T7 DNA polymerase; 2) devising and synthesizing a primer according to a gene sequence of Sau and a sequence TBD published by GenBank, and amplifying by Overlap PCR to insert the TBD into the corresponding position of the gene sequence of Sau to prepare a Sau-TBD segment having a purification tag and a restriction site; 3) cloning the Sau-TBD segment obtained in (2) to an expression vector pTrc99A to construct a recombinant vector pTrc99A-Sau-TBD; and 4) transforming E. coli by the recombinant vector pTrc99A-Sau-TBD and inducing protein expression.
[0017] In accordance with still another embodiment of the invention, there is provided a method for using the DNA polymerase possessing continuous catalytic capacity and salt tolerance in isothermal nucleic acid amplification.
[0018] Advantages of the DNA polymerase possessing continuous catalytic capacity and salt tolerance according to embodiments of the invention are summarized as follows:
[0019] The DNA polymerase used in the isothermal nucleic acid amplification is biomolecularly constructed. The DNA polymerase after construction maintains the same catalytic activity as the original, but the continuous catalytic capacity thereof is significantly improved and the salt tolerance thereof in the recombinase-mediated isothermal nucleic acid amplification reaction is also improved. When conducting the nucleic acid detection in the field or the site, because the simple DNA extraction technique is employed, DNA samples prepared are usually not pure enough and may contain amplification inhibiting substances like salt ions. The DNA polymerase after construction has much higher salt tolerance and is capable of significantly improving the DNA amplification effect of the recombinase-mediated isothermal nucleic acid amplification in the field or the site, thus having wide application prospect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention is described hereinbelow with reference to the accompanying drawings, in which:
[0021] FIG. 1 illustrates three-dimensional structure prediction and overlapping match results of bacteriophage T7 DNA polymerase and Sau protein;
[0022] FIG. 2 shows insertion position of TBD domain into Sau protein sequence;
[0023] FIG. 3 illustrates construction of a recombinant plasmid of pTrc99A-Sau-TBD;
[0024] FIG. 4 shows identification results of a recombinant plasmid of pTrc99A-Sau-TBD by enzyme digestion, in which, M indicates Marker, 1 indicates a plasmid pTrc99A-Sau-TBD, 2 indicates double digestion products of the plasmid pTrc99A-Sau-TBD;
[0025] FIG. 5 is SDS-PAGE analysis results of a recombinant protein Sau-TBD, in which, M indicates Marker, 1 indicates a protein before induction, 2 indicates a protein after induction, 3 indicates a supernatant, 4 indicates a precipitate, 5 indicates a flow solution, and 6 indicates a target protein (approximately 73 KD);
[0026] FIG. 6 is a diagram showing construction of recombinant plasmid pET28a-Trx;
[0027] FIG. 7 shows identification results of a recombinant plasmid of pET28a-Trx by enzyme digestion, in which, M indicates Marker, 1 indicates a plasmid pET28a-Trx, 2 indicates double digestion products of the plasmid pET28a-Trx;
[0028] FIG. 8 shows SDS-PAGE analysis results of a recombinant protein Trx, in which, M indicates Marker, 1 indicates a protein before induction, 2 indicates a protein after induction, 3 indicates a supernatant, 4 indicates a precipitate, 5 indicates a flow solution, and 6 indicates a target protein (approximately 13 KD);
[0029] FIG. 9 shows electrophoresis peaks for testing continuous catalytic capacity of Sau and Sau-TBD, in which, an abscissa indicates an addition of nucleotides, and an ordinate indicates a fluorescence intensity; and
[0030] FIG. 10 shows electrophoresis results of salt tolerances of Sau and Sau-TBD.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0031] For further illustrating the invention, experiments detailing a DNA polymerase possessing continuous catalytic capacity and salt tolerance are described below. It should be noted that the following examples are intended to describe and not to limit the invention.
[0032] Source of biomaterials of the invention:
[0033] 1. S. aureus CICC21600 was purchased from China Center of Industrial Culture Collection (CICC), and E. coli BL21 (DE3) was purchased from Novagen company.
[0034] 2. Primers and plasmid pUC57-TBD containing the TBD gene was authorized to BGI Biological Technology Co., Ltd for synthesis.
[0035] 3. Vectors pTrc-99A and pET28a were purchased from Novagen company.
Example 1
[0036] Three-dimensional structures of the bacteriophage T7 DNA polymerase and the Sau were predicted on swiss-model website (http://swissmodel.expasy.org/) according to the sequence information disclosed by GenBank. Thereafter, the three dimensional structures of the bacteriophage T7 DNA polymerase (PDB: 2AJQ_A) and the Sau (PDB: 4DQQ_D) were compared using the DaliLite function on EBI website (http://www.ebi.ac.uk/Tools/structure/dalilite/) so as to find the position in the Sau protein sequence corresponding to the TBD and determine the substitution sequence (as shown in FIGS. 1-2 ).
Example 2
[0037] Preparation of the Sau-TBD segment is illustrated hereinbelow.
[0038] 1. The sequence of the TBD (registration number in NCBI is ACY75853.1, and sequence is represented by SEQ ID No. 3) of the bacteriophage T7 DNA polymerase was synthesized according to the GenBank and related literatures.
[0039] 2. Primers were devised and synthesized according to the gene sequence of Sau (reference sequence number in NCBI is YP_006237943.1) and the sequence information of TBD disclosed by GenBank.
[0000]
PT1_F:
(SEQ ID No. 4)
5′-CATGCCATGGAACATCATCATCATCATCATTCAGCAAGCGTTGAAG-
3′ (NcoI)
PT1_R:
(SEQ ID No. 5)
5′-GATACCACGA ACCAGCTGCATCATGGAT-3′
PT2_F:
(SEQ ID No. 6)
5′-GTTGTGTTTAACCCTTCGTCTCCTAAGCAATTAGGTG-3′
PT2_R:
(SEQ ID No. 7)
5′-CGCGGATCCTTATTTTGCATCATACC-3′ (BamHI)
TBD_F:
(SEQ ID No. 8)
5′-TGCAGCTGGTTCGTGGTATCAGCCTAAAGG-3′
TBD_R:
(SEQ ID No. 9)
5′-CACCTAATTGCTTAGGAGACGAAGGGTTAAACACAAC-3′
[0040] 3. PT1_F/PT1_R and PT2_F/PT2_R were used as specific primers and genosome of S. aureus CICC21600 was used as the template to perform PCR amplification respectively. The specific primer TBD_F/TBD_R was adopted as the specific primer, and the artificially synthesized plasmid pUC57-TBD containing the TBD gene was used as the template for performing PCR amplification. PCR reaction system is a common amplification system recommended by PrimeSTAR HS (TAKARA), and the PCR reaction program was as follows: predenaturation at 98° C. for 2 min, followed by 27 cycles of denaturation at 98° C. for 10 s, annealing at 55° C. for 30 s, and extension at 72° C. for 1 min, and finally followed by extension at 72° C. for 10 min. Reaction products were preserved at 4° C.
[0041] 4. PT1, PT2, TBD segments were recovered using a gel extraction kit for PCR products as follows:
[0042] 1) An agarose gel containing a target segment was cut using a surgical blade under an ultraviolet light and placed in a 1.5 mL centrifuge tube.
[0043] 2) An extraction buffer was added to the centrifuge tube according to a ratio of 1:3 to yield a mixed solution.
[0044] 3) The centrifuge tube was then placed in a water bath at a constant temperature of 50° C. for 10 min, during which the centrifuge tube was gently reversed every two minutes.
[0045] 4) The mixed solution was transferred to a spin column and the spin column was centrifuged at a rotational speed of 6000×g for 1 min. A solution in a collection tube was discarded.
[0046] 5) 500 μL of the extraction buffer was added to the spin column which was then centrifuged at a rotational speed of 12 000×g for 1 min, and a solution in a liquid collection tube was discarded.
[0047] 6) 750 μL of a wash buffer was added to the spin column which was then centrifuged at the rotational speed of 12 000×g for 1 min, and a solution in the liquid collection tube was discarded.
[0048] 7) The spin column was placed into the collection tube and centrifuged at the rotational speed of 12 000×g for 1 min. The spin column was then transferred to an aseptic 1.5 mL EP tube.
[0049] 8) 50 μL of an elution buffer was added to the spin column and the spin column was allowed to stand for 1 min at the room temperature. Thereafter, the spin column was centrifuged at the rotational speed of 12 000×g for 1 min so as to collect the target DNA segments in a micro centrifuge tube. The target DNA segments were preserved at a temperature of −20° C.
[0050] 5. PT1 segment and TBD segment were used as templates and PT1_F and TBD_R were used as primers to perform overlap PCR. The amplification system was as follows:
[0000]
10* PrimeSTAR Buffer
10
μL
dNTP
4
μL
PT1
0.2
μL
TBD
0.2
μL
PT1_F
2
μL
TBD_R
2
μL
PrimeSTAR Pol
0.5
μL
ddH 2 O
31.1
μL
[0051] The PCR reaction program was as follows: predenaturation at 98° C. for 2 min, followed by 27 cycles of denaturation at 98° C. for 10 s, annealing at 55° C. for 30 s, and extension at 72° C. for 1 min, and finally followed by extension at 72° C. for 10 min. Reaction products were preserved at 4° C.
[0052] 6. PT1-TBD segment was recovered using the gel extraction kit for PCR products.
[0053] 7. PT1-TBD segment and PT2 segment were used as templates and PT1_F and PT2_R were used as primers to perform overlap PCR. The amplification system was as follows:
[0000]
10* PrimeSTAR Buffer
10
μL
dNTP
4
μL
PT1-TBD
0.2
μL
PT2
0.2
μL
PT1_F
2
μL
PT2_R
2
μL
PrimeSTAR Pol
0.5
μL
ddH 2 O
31.1
μL
[0054] The PCR reaction program was as follows: predenaturation at 98° C. for 2 min, followed by 27 cycles of denaturation at 98° C. for 10 s, annealing at 58° C. for 30 s, and extension at 72° C. for 1 min, and finally followed by extension at 72° C. for 10 min. Reaction products were preserved at 4° C.
[0055] 8. The PT1-TBD-PT2 (Sau-TBD) segment was recovered by gel extraction kit for PCR products.
Example 3
[0056] Construction of recombinant plasmid pTrc99A-Sau-TBD is illustrated hereinbelow:
[0057] 1. Sau-TBD segment and vector pTrc99A were digested by enzyme at 37° C. for 2 hrs and the digestion products were recovered by gel extraction. The enzyme digestion system was as follows:
[0000]
10 × NEB Buf 3
5
μL
NcoI
1
μL
BamHI
1
μL
BSA
0.5
μL
Sau-TBD/pTrc99A
42.5
μL
[0058] 2. Sau-TBD and pTrc99A segments after digestion were ligated by a T4 ligase overnight at 16° C. using the following ligation system:
[0000]
10 × Ligase Buf
2.5
μL
T4 ligase
1
μL
Sau-TBD
8
μL
pTrc99A
8.5
μL
[0059] 3. Transformation: competent cells of E. coli DH5α were taken out from −70° C. refrigerator and buried in ice. Ligation products were taken out from a water bath at the temperature of 16° C., removed from a sealing film, and placed on the ice. When the competent cells were melted, the ligation products were added to 100 μL of the competent cells of DH5a and uniformly mixed. After 30 min treatment by the ice, the mixture was heated at 42° C. for 90 s, and then treated by the ice again. Then 800 μL of an LB culture medium was added to the mixture, a resulting mixture was shaken on a shaking table at a rotational speed of 170 rpm at the temperature of 37° C. for 1 hr. A culture was then centrifuged at a rotational speed of 5 000 rpm for 5 min. A part of supernatant was discarded to leave approximately 100 μL of the remaining. The remaining supernatant and a precipitant were mixed and a resulting mixture was then smeared on a Kanamycin resistant LB plate and incubated at 37° C. for between 12 and 16 hrs.
[0060] 4. A plurality of pTrc99A-Sau-TBD colonies were picked and cultured on a shaking table at the temperature of 37° C. overnight, then an amount of plasmid DNA was extracted as follows:
[0061] 1) 2 mL of a fresh bacterial liquid was collected and centrifuged at the rotational speed of 12 000×g for 1 min, and a supernatant was then discarded, leaving a bacterial precipitate.
[0062] 2) 250 μL of Buffer S1 was added to suspend the bacterial precipitate. A suspension was required to be uniform to avoid bacterial mass.
[0063] 3) 250 μL of Buffer S2 was added to the suspension, a resulting solution was gently and fully reversed for between 4 and 6 times to make bacteria totally decomposed.
[0064] 4) 350 μL of Buffer S3 was added, a resulting mixture was fully reversed for mixing for between 6 and 8 times, and then centrifuged at the rotational speed of 12 000×g for 10 min.
[0065] 5) A supernatant was sucked and transferred to a preparation tube which was then centrifuged at the rotational speed of 12 000×g for 1 min. A filtrate was then discarded.
[0066] 6) 500 μL of a Buffer W1 was added to the preparation tube which was then centrifuged at the rotational speed of 12 000×g for 1 min. A filtrate was then discarded.
[0067] 7) The preparation tube was put back in the collection tube, added with 700 μL of a Buffer W2, and centrifuged at the rotational speed of 12 000×g for 1 min, then a filtrate was discarded.
[0068] 8) The preparation tube was centrifuged at the rotational speed of 12 000×g for 1 min.
[0069] 9) The preparation tube was then transferred to a new 1.5 mL centrifuge tube, and 70 μL of an Eluent was added to the preparation tube. The preparation tube was allowed to stand at the room temperature for 1 min, and then centrifuged at the rotational speed of 12 000×g for 1 min. Resulting products were preserved at the temperature of −20° C.
[0070] 5. Identification of the recombinant plasmid
[0071] 1) Identification of the recombinant plasmid by PCR
[0072] The extracted plasmid were amplified by PCR, and performed with 1% agarose gel electrophoresis to observe the results.
[0073] 2) Identification of recombinant plasmid by double digestion
[0074] The double digestion system of pTrc99A-Sau-TBD was as follows:
[0000]
10 × NEB Buf 3
5
μL
NcoI
1
μL
BamHI
1
μL
BSA
0.5
μL
Sau-TBD/pTrc99A
42.5
μL
[0075] The digestion was performed at the temperature of 37° C. for 2 hrs. 1% agarose gel electrophoresis was performed to identify the results, which was shown in FIG. 4 .
[0076] 6. Recombinant plasmid that was identified to be correct by digestion was sent to sequence.
Example 4
[0077] The expression and purification of the recombinant protein is introduced hereinbelow:
[0078] 1. Recombinant expression plasmid pTrc99A-Sau-TBD testified by sequencing to be positive was then transformed into E. coli expression strain BL21 (DE3). A signal colony was picked and incubated in an LB liquid culture medium containing kanamycin on a shaking table at the temperature of 37° C. overnight.
[0079] 2. A bacterial liquid was inoculated to 500 mL of the LB liquid culture medium containing kanamycin according to a ratio of 1/100 and cultured on the shaking table at the temperature of 37° C. When the OD 600 reached 0.6, IPTG was added until a final concentration was 0.5 mmol/L, then the induction was performed. An expression vector contrast group was designed, a bacterial liquid was collected 4 hrs after the induction expression, centrifuged at the rotational speed of 12 000 rpm for 10 min, and a supernatant was removed.
[0080] 3. Ni-NTA loading buffer (20 mM Na 3 PO 4 , 0.5 M NaCl, 10 mM imidazole, pH 7.4) was used to heavily suspend a bacteria precipitate. The bacteria precipitate was then treated with ultrasonication, centrifuged at 10 000 rpm for 20 mM. Thereafter, a supernatant and a precipitate were performed with SDS-PAGE electrophoresis.
[0081] 4. AKTA protein purification system and Ni Sepharose 6 Fast Flow affinity chromatography were employed to perform affinity purification of the target protein, in which the loading buffer (20 mM Na 3 PO 4 , 0.5 M NaCl, 10 mM imidazole, pH 7.4) and the elution buffer (20 mM Na 3 PO 4 , 0.5 M NaCl, 500 mM imidazole, pH 7.4) were adopted. Protein sample at an elution peak was collected and treated by dialysis (10 mM Tris-HCl pH 7.5, 50 mM KCl, 1 mM DTT, 1 mM EDTA, 0.1% NP-40) overnight at the temperature of 4° C.
[0082] 5. AKTA protein purification system and HiTrap Heparin HP affinity chromatography were employed to perform a secondary purification on the protein sample after dialysis overnight, in which the loading buffer (10 mM Na 3 PO 4 , pH 7.0) and the elution buffer (10 mM Na 3 PO 4 , 1 M NaCl, pH 7.0) were adopted. Protein sample at an elution peak was collected and treated by dialysis (10 mM Tris-HCl pH 7.5, 50 mM KCl, 1 mM DTT, 1 mM EDTA, 0.1% NP-40) overnight at the temperature of 4° C. The protein samples after the dialysis was preserved at the refrigerator at the temperature of −80° C. Electrophoresis results of protein samples at different phases of the purification process were shown in FIG. 5 .
Comparative Example 1
[0083] Because TrxA was necessary herein, a premier was devised and synthesized according to the gene sequence of TrxA disclosed by GenBank (reference sequence number in NCBI is NC_000913.2) so as to prepare the protein:
[0000]
Trx_F:
(SEQ ID No. 10)
5′-CATGCCATGGGCAGCGATAAAATTATTCACCTG-3′ (NcoI)
Trx_R:
(SEQ ID No. 11)
5′-TTTTCCTTTTGCGGCCGCCGCCAGGTTAGCGTCGAGG-3′
(NotI)
[0084] Trx_F/Trx_R were used as specific premiers and genome of E. coli BL21 (DE3) was used at the template to perform PCR amplification. The amplified segments were then recovered and ligated to pET28a, followed by transformation, expression, and SDS-PAGE electrophoresis. All experiment methods are common operations, which can refer to Examples 2-4, and results thereof are shown in FIGS. 6-8 .
[0085] Hereinbelow, the polymerization activities were compared between the polymerase Sau before the protein construction and the polymerase Sau-TBD after the protein construction:
[0086] 1. Test reaction: the synthesized premier M13-40 and ssM13mp18 DNA (NEB) were annealed in the standard recombinase-mediated isothermal nucleic acid amplification reaction system, then 300 μM of dNTPs and 1.5 μM of (Sau/Sau-TBD) were respectively added. An additional 1.5 μM of TrxA was then added to the Sau-TBD reaction system. Finally, 14 mM of MgAc was added to each reaction tube to start the reaction. Amplification reaction was performed at the temperature of 37° C., and samples at different time points were collected for testing.
[0000]
The sequence of M13-40 is:
5′-GTTTTCCCAGTCACGACG-3′
(SEQ ID No. 12)
[0087] 2. Control reaction: the synthesized premiers M13-40 and ssM13mp18DNA (NEB) were annealed in 10× ThermoPol Buffer, then 300 μM of dNTPs and 1.5 μM of Bst (NEB) were respectively added. Amplification reaction was performed at 65° C., and samples were collected at different time points for testing.
[0088] 3. An equivalent volume of PicoGreen (Invitrogen) digested at a ratio of 1:200 were added to amplification products and uniformly mixed to allow for reaction for between 2 and 5 min in the dark. Fluorescence intensities of different reaction tubes were tested by microplate reader (Fluostar Optima, BMG LABTECH).
[0089] 4. The initial reaction rates of Sau and Sau-TBD were compared to the initial reaction rate of Bst, the polymerization activity of which was known, so as to obtain the polymerization activity of Sau and Sau-TBD (containing Trx), results of which were listed in Table 1.
[0000]
TABLE 1
Results of polymerization activities
Polymerization activities (units/mg protein)
Polymerase
−TrxA
+TrxA
Sau
3089
3099
Sau-TBD
1316
2864
[0090] It is known from Table 1 that the polymerization activity of Sau protein is not influenced by the addition of the TrxA. While without the assistance of the TrxA, the polymerization activity of Sau-TBD is only 1316 units/mg. Under the assistance of TrxA, the polymerization activity of Sau-TBD is improved by at least two folds and reaches 2864 units/mg. According to the difference of the molar mass, the polymerization activity per molar unit of Sau and Sau-TBD have no significant difference.
Comparative Example 2
[0091] The continuous synthetic capacities were compared between the polymerase Sau before the protein construction and the polymerase Sau-TBD after the protein construction:
[0092] 1. The whole reaction was performed in the dark condition: fluorescent labeled primers M13-40LF and ssM13mp18 DNA(NEB) were annealed in the standard recombinase-mediated isothermal nucleic acid amplification reaction system, then 300 μM of dNTPs and polymerase (Sau/Sau-TBD) were respectively added. Polymerase (a ratio of the polymerase to the template after annealing of the primer was 1:100-1:2000) of different concentrations were respectively added to different reaction tubes to find the conditions of reaching continuous synthetic state for different polymerses (generally enzyme possessing high continuous catalytic capacity requires a relative high ratio of the polymerase to the template after the annealing of the primer to reach the continuous synthetic state). An additional 50 mM of TrxA was added to the Sau-TBD reaction system. Finally 14 mM of MgAc was added to each reaction tube to initiate the reaction.
[0093] Sequence of M13-40LF is as follows:
[0000]
(SEQ ID No. 13)
5′-FAM-GTTTTCCCAGTCACGACGTTGTAAAACGACGGCC-3′
[0094] 2. The whole reaction was performed in the dark: the amplification reaction was performed at 37° C. In order to prevent the polymerase from extending the same amplification product for multiple times, the reaction products were taken out at different time periods. When the reaction was finished, 50 mM of EDTA was added to each reaction tube to end the reaction.
[0095] 3. The reaction product was diluted by the loading buffer, and the samples was load to DNA sequencer (3730xl DNA Analyzer, Applied Biosystems), and fluorescence peaks of the electrophoresis of reaction product and the length data of the corresponding amplification products were shown in FIG. 5 .
[0096] 4. Length data of the amplification products of Sau and Sau-TBD were analysed, and an average length of the amplified products of each polymerase was calculated according to the following equation:
[0000] log( n I /n T )=( n− 1)log P I +log(1− P I )
[0097] In the equation, n I represents a length of a signal peak that is higher than the background, and n T represents a sum of signal intensity of all products. A curve of log(n I /n T ) was charted in relation to n−1, in which, n represents a number of bases polymerized at an end of the primers. Thus, it was known from the equation that an average amplification length of the primer was 1/(1−P I ), in which P I represents a probability that the polymerization does not stop at the position of I, results were listed in Table 2.
[0000]
TABLE 2
Continuous catalytic capacities of polymerases
Micro continuous
Average amplification length of
Polymerases
synthetic capacities (P I )
primers (nt) [1/(1 − P I )]
Sau
0.9726 ± 0.0006
36.5 ± 0.8
Sau-TBD (in the
0.9865 ± 0.0001
74.1 ± 0.6
presence of TrxA)
Sau-TBD (in the
0.7135 ± 0.004
3.5 ± 0.06
absence of TrxA)
[0098] It is known from Table 2 and FIG. 9 that the insertion of the TBD domain into the polymerase Sau make the average amplification length of the primer reduced from 36.5 nt to 3.5 nt, such decrease may because the TBD domain influences the binding effect of the Sau polymerase on the DNA chain. While under the assistance of the TrxA, the average amplification length of the primer of the Sau-TBD is significantly improved by at least 20 folds and reaches 74.1 nt, which is more than two times of the wild-type Sau polymerase. This indicates that under the binding effect of TrxA to the DNA, the continuous catalytic capacity of the Sau-TBD after construction has is significantly enhanced.
Comparative Example 3
[0099] The salt tolerances were compared between the polymerase Sau before the protein construction and the polymerase Sau-TBD after the protein construction:
[0100] 1. λ phage DNA (130 pg/μL) was used as the template, and 500_F/500_R is used as the primer, and the amplification reaction was performed in the common recombinase-mediated isothermal nucleic acid amplification reaction system. KAc of different concentrations were added into different reaction tubes so as to study the tolerance of the system to the salt concentrations.
[0000]
(SEQ ID No. 14)
500_F:
5′-ACTACTAAATCCTGAATAGCTTTAAGAAGG-3′
(SEQ ID No. 15)
500_R:
5′-CAGAAAGCTAAATATGGAAAACTACAATAC-3′
[0101] 2. The reaction was performed at 37° C. for 40 mM. After the reaction, an equivalent volume of phenol chloroform was added to the system for extraction. 5 μL of a supernatant sample yield from the extraction was collected and performed with electrophoresis in 1.2% agarose gel, and the electrophoresis result is shown in FIG. 10 .
[0102] It is indicated from the results illustrated in FIG. 10 , Sau can be normally amplified in condition of relative low KAc concentration (<160 mM). When the concentration of KAc reaches 180 mM, Sau is uncapable of amplifying to yield visible band. In contrast, Sau-TBD is capable of amplifying at 180 mM under the help of TrxA to obtain clear band. It is concluded that Sau-TBD (in the presence of TrxA) has much higher salt tolerance in the recombinase-mediated isothermal nucleic acid amplification system, thus, it has significant advantage in the amplification process of DNA samples that have relatively higher salt.
[0103] Unless otherwise indicated, the numerical ranges involved in the invention include the end values. While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. | A DNA polymerase, having an amino acid sequence represented by SEQ ID No. 2, or a derivative of the amino acid sequence by substitution, deletion, or addition of at least one amino acid residue. The DNA polymerase is a hybrid DNA polymerase prepared by inserting a thioredoxin binding domain (TBD) of bacteriophage T7 DNA polymerase into a DNA polymerase I (Sau) of Staphylococcus aureus . A method for preparing the DNA polymerase includes: 1) determining a corresponding position and a target substitution sequence in Sau protein for the TBD of the bacteriophage T7 DNA polymerase; 2) devising and synthesizing a primer according to a gene sequence of Sau and a sequence TBD published by GenBank; 3) cloning the Sau-TBD segment acquired in (2) to an expression vector pTrc99A to construct a recombinant vector pTrc99A-Sau-TBD; and 4) transforming Escherichia coli by the recombinant vector pTrc99A-Sau-TBD and inducing protein expression. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a cooling apparatus for a closed housing cut off from the outside atmosphere, more specifically to a cooling apparatus provided with a heat-pipe-type heat exchanger and adapted to be mounted on a closed housing which contains therein electronic equipment to be protected from the outside atmosphere.
Recently, the application of electronic equipment, especially computers, have been remarkably extended, and process computers have come to enjoy use in even job sites in factories. Ambient air in a job site may contain dust or poisonous gas which has a bad influence upon the process computer and may cause malfunction thereof. In order to be protected from the outside environment, therefore, the process computer needs to be contained in a closed housing.
During operation, however, the process computer generates heat, whereas the closed housing cannot be ventilated without affecting the performance of the process computer. Unless the interior of the housing is cooled, therefore, the process computer cannot help being heated by heat which is internally generated from itself. If heated, the process computer is liable to malfunction. Accordingly, there is proposed a cooling apparatus for a closed housing provided with a heat-pipe-type heat exchanger.
FIG. 1 shows a cooling apparatus 12 for a closed housing 10. The cooling apparatus 12 is provided with a cooling chamber 14 which is attached to one side face of the closed housing 10 in which a process computer is provided. The cooling chamber 14 is divided into two isolated parts, upper and lower chambers 18 and 20, by a partition wall 16 extending horizontally. The upper chamber 18 communicates with the outside air by means of an outer inlet opening 22 and an outer outlet opening 24. The lower chamber 20 communicates with the interior of the closed housing 10 by means of an inner inlet opening 26 and an inner outlet opening 28. Exhaust fans 30 and 32 are disposed inside the outer outlet opening 24 of the upper chamber 18 and the inner outlet opening 28 of the lower chamber 20, respectively. The outside air flows through the upper chamber 18, and air in the housing 10 flows through the lower chamber 20 by means of their corresponding fans 30 and 32. A plurality of heat pipes 34 containing a refrigerant therein airtightly penetrate the partition wall 16 along the vertical direction each with both end portions located in the upper and lower chambers 18 and 20, respectively. Each heat pipe 34 is fitted with a multitude of fins 36 along the axial direction. The upper end portions of the heat pipes 34 are defined as a refrigerant condensing section, while the lower end portions are defined as a refrigerant evaporating section.
In the cooling apparatus thus constructed, the interior of the closed housing 10 is cooled in accordance with the following processes. Air in the closed housing 10 heated by heat generated from the process computer is introduced through the inner inlet opening 26 into the lower chamber 20 by the fan 32. The introduced air is caused to make heat exchange by means of the evaporating section of the heat pipes 32 and the fins 36. As a result, the heat of the air is absorbed by the heat pipes 34 to cool the air, and the refrigerant is evaporated at the evaporating section of the heat pipes 34 to which the heat is applied. The cooled air is returned through the inner outlet opening 28 to the interior of the housing 10 to cool the same.
Meanwhile, the heated and evaporated refrigerant rises up through the heat pipes 34 to reach the condensing section inside the upper chamber 18. The outside air is introduced through the outer inlet opening 22 into the upper chamber 18 by the fan 30, and is caused to make heat exchange by means of the condensing sections of the heat pipes 34 and the fins 36. Accordingly, the heat of the refrigerant is absorbed by the outside air. As a result, the outside air is heated, while the refrigerant is cooled and condensed. The condensed refrigerant falls down to the evaporating section by its own weight, and the heated outside air is discharged through the outer outlet opening 24 into the outside space.
Thus, the air inside the closed housing 10 is caused to exchange heat with the outside air and thence to be cooled by means of the heat pipes 34. Namely, the housing 10 is cooled inside as it is closed, so that the process computer contained in the housing 10 may be protected from dust and heat.
Mounted on one side face of the closed housing 10, however, the prior art cooling apparatus 12 has the following drawbacks. First, the side face of the housing 10 is subject to a restriction on size depending on the setting conditions of the housing 10, as well as to many other restrictions attributed to the attachment of a door, meter, harness, connector, etc., thereon, so that the cooling apparatus 12 need be designed according to the particulars of the individual housing 10. Accordingly, it is difficult to put the cooling apparatus 12 to general use, and the apparatus cannot enjoy any reduction in cost. Secondly, due to the setting location of the cooling apparatus 12 on the side wall of the housing 10, the housing 10 requires an increased setting space when it is arranged in line with another one or put by a wall. Thirdly, whereas the upper portion is at the highest temperature inside the housing 10, the cooling apparatus 12 is attached to one side face of the housing 10 with the evaporating section located in the lower position. Accordingly, the air inlet opening 26 in the housing 10 has to be located in a relatively low position, constituting a hindrance to the improvement of cooling efficiency.
SUMMARY OF THE INVENTION
This invention is contrived in consideration of these circumstances, and is intended to provide a cooling apparatus for a closed housing, capable of enjoying general use and improved in compactness and cooling efficiency.
According to an aspect of this invention, there is provided a cooling apparatus for a housing which is provided with an opening at the top thereof, comprising a casing located on the top of the housing and including a bottom plate to close the opening and a chamber, a partition wall provided in the casing to divide the chamber into a first chamber section and a second chamber section, the bottom plate having a first inlet opening and a first outlet opening, the first chamber section communicating with the interior of the housing by means of the first inlet opening and first outlet opening, and the casing having a second inlet opening and a second outlet opening, the second chamber section communicating with the exterior of the housing by means of the second inlet opening and second outlet opening, heat exchange means including at least one heat pipe provided in the casing through the partition wall with coolant therein for exchanging heat in the first chamber section with heat in the second chamber section, the heat pipe having one end portion in the first chamber section and the other end portion in the second chamber section, and inclining with the one end portion located lower than the other end portion, a first fan provided in the first chamber section to generate a first air stream passing through the first inlet opening and first outlet opening and passing by the one end portion of the heat pipe, a second fan provided in the second chamber section to generate a second air stream passing through the second inlet and second outlet openings and passing by the other end portion of the heat pipe, and driving means provided in the casing for driving the first and second fans.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side sectional view schematically showing a prior art cooling apparatus;
FIG. 2 is a partially broken perspective view of a cooling apparatus according to one embodiment of this invention; and
FIG. 3 is a top view of the apparatus shown in FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the accompanying drawings of FIGS. 2 and 3, there will be described in detail a cooling apparatus for a closed housing according to one embodiment of this invention.
In the drawings, reference numeral 40 designates a housing which contains therein electronic equipment (not shown) such as a process computer. The top of the housing 40 opens substantially over the length and breadth thereof, and a flange portion for mounting a cooling apparatus 42 as mentioned later is formed on the edge of the top of the housing 40 along the whole circumference thereof, inwardly projected a little.
The cooling apparatus 42 is mounted by means of the flange portion on the top of the housing 40 so as entirely to block up the opening portion of the housing 40. Thus, the housing 40 is closed up airtightly to protect the electronic equipment therein from dust or any poisonous gas.
The cooling apparatus 42 is provided with a casing 44 in the form of a rectangular prism. The interior of the casing 44 is defined as a heat exchange chamber. A partition wall 46 extends vertically inside the casing 44 to divide the heat exchange chamber into two parts, a cooling chamber 48 and a radiating chamber 50. The cooling chamber 48 and the radiating chamber 50 are isolated airtightly from each other.
Two openings 52 and 54 are formed in line in the bottom plate of the casing 44 on the cooling chamber side along the partition wall 46. The one opening 52 is defined as an inner inlet opening, while the other opening 54 is defined as an inner outlet opening. The interior of the housing 40 and the cooling chamber 48 communicate with each other by means of these openings 52 and 54. Disposed in the cooling chamber 48 is a baffle plate 56 which is located between the two openings 52 and 54 and vertically extends to intersect the partition wall 46 at right angles thereto. The baffle plate 56 divides the cooling chamber 48 into two parts, leaving a gap only between its upper edge and the top plate of the casing 44 whereby the two divided parts or spaces are allowed to communicate with each other. In that space which is on the side of the inner outlet opening 54 is provided a fan 58 for circulating air in such way that air first flows from the cooling chamber 48 into the housing 40 through the inner outlet opening 54 and then from the housing 40 into the chamber 48 through the inner inlet opening 52. In this embodiment, a fan is used for the fan 58. The sirocco fan 58 has its discharge port 59 opening into the inner outlet opening 54 and its driven shaft 58A (FIG. 3) intersecting the partition wall 46 at right angles thereto.
Two openings 60 and 62 are formed in line in the top plate of the casing 44 on the radiating chamber side along the partition wall 46. The one opening 60 is defined as an outer inlet opening, while the other opening 62 is defined as an outer outlet opening. As shown in FIG. 3, the outer inlet and outlet openings 60 and 62 are located on the same sides of the partition wall 46 with the inner inlet and outlet openings 52 and 54, respectively. The outer space of the casing 44 and the radiating chamber 50 communicate with each other by means of these openings 60 and 62. Disposed in the radiating chamber 50 is another baffle plate 64 which is located between the two openings 60 and 62 and vertically extends to intersect the partition wall 46 at right angles thereto. The baffle plate 64 divides the radiating chamber 50 into two parts, leaving a gap only between its lower edge and the bottom plate of the casing 44 whereby the two divided parts or spaces are allowed to communicate with each other. In that space which is on the side of the outer outlet opening 62 is provided another fan 66 for circulating air in such way that air first flows from the radiating chamber 50 into the outer space through the outer outlet opening 62 and then from the outer space into the radiating chamber 50 through the outer inlet opening 60. In this embodiment, a fan is used for the another fan 66. The fan 66 has its another discharge port 65 opening into the outer outlet opening 62 and its driven shaft 66A (FIG. 3) formed coaxially and integrally with the driven shaft 58A of the aforesaid fan 58.
A common motor 67 for driving the two fans 54 and 66 is disposed between these fans 54 and 66 and inside the radiating chamber 50. A driving shaft of the motor 67 is connected directly and coaxially with the driven shafts 58A and 66A of the fans 54 and 66. Accordingly, the driven shafts 58A and 66A of the fans 58 and 66 are rotated in accordance with the rotation of the driving shaft of the motor 67 to cause the fans 58 and 66 to blow.
The cooling apparatus 42 is provided with a heat exchanger 68 which extends from a space inside the cooling chamber 48 on the inner inlet opening side to a space inside the radiating chamber 50 on the outer inlet opening side. The heat exchanger 68 includes a plurality of heat pipes 70 in a single layer, airtightly penetrating the partition wall 46, each having one end located severally in the cooling chamber 48 and another end in the radiating chamber 50, and arranged at regular intervals. These heat pipes 70 are defined within one and the same plane, which is inclined at an angle of approximately 10° to a horizontal plane with the end portion on the cooling chamber side located lower than the other end portion. The lower portions of the heat pipes 70 are located over the inner inlet opening 52, while the upper portions are located under the outer inlet opening 60. Being of a wickless type, the heat pipes 70 are each composed of a straight pipe body sealed at either end and a refrigerant sealed in the pipe body. The pipe body is formed of copper, and Freon R-12 (trademark) is used for the refrigerant. The lower portions of the heat pipes 70 inside the cooling chamber 48 are defined as a refrigerant evaporating section, while the upper portions of the heat pipes 70 inside the radiating chamber 50 are defined as a refrigerant condensing section.
The heat pipes 70 are fitted through the full length with a plurality of fins 72 which extend at regular intervals and in parallel with the partition wall 46. The fins 72 are formed of aluminum, and are intended to increase the area in contact with air to improve endothermic/exothermic effect.
Now there will be described the operation of the cooling apparatus 42 with the above-mentioned construction.
When the motor 67 is started, both fans 54 and 66 are driven. Then, heated air in the closed housing 40 forms a circulating air stream which passes through the inner inlet opening 52, the evaporating section of the heat exchanger 68, the gap between the one baffle plate 56 and the top plate of the casing 44, the one fan 58, and the inner outlet opening 54, and returns to the housing 40. On the other hand, the outside air colder than the air inside the closed housing 40 forms another circulating air stream which passes through the outer inlet opening 60, the condensing section of the heat exchanger 68, the gap between the other baffle plate 64 and the bottom plate of the casing 44, the other fan 66, and the outer outlet opening 62, and returns to the outside.
Thereupon, the air heated in accordance with the operation of the process computer in the housing 40 exchanges heat with the evaporating section of the heat exchanger 48 as the former passes through the latter. Namely, at the evaporating section, the refrigerant in a liquid phase absorbs heat from the ambience to be evaporated. Thus, the ambient air at the evaporating section is cooled. The evaporated refrigerant rises up through the heat pipes 70 to reach the condensing section, where it radiates heat to the ambience to be liquefied. Thus, the ambient air at the condensing section is heated. The liquefied refrigerant falls down the heat pipes 70 by its own weight to return to the evaporating section.
Accordingly, the heated air in the housing 40 is cooled as it passes through the evaporating section of the heat exchanger 68, and thus the air temperature inside the housing 40 is prevented from rising. On the other hand, the air heated at the condensing section of the heat exchanger 68 is discharged into the outside. Hereupon, the temperature of the outside air will never greatly be increased by any substantial difference in mass.
According to this embodiment, as described in detail above, the cooling apparatus 42 is mounted on the top of the housing 40. Therefore, the setting area required for the housing 40 never increases, so that the restrictions on the setting location of the housing 40 can be reduced by a large margin. Moreover, since the air at the upper portion of the housing 40 which is at the highest temperature can be cooled, the cooling efficiency may greatly be improved.
Since the setting space of the cooling apparatus 42 is shifted from the side face of the housing 40, which is conventionally fitted with various components and implements, to the top face clear of obstacles, the degree of freedom of the housing 40 in design may be improved to facilitate installation work and to ensure general use of the cooling apparatus 42.
Further, the mounting of the cooling apparatus 42 on the top of the housing 40 eliminates the conventional restrictions on the length of the heat pipes that are inevitable in the case where the cooling apparatus is mounted on the side face of the housing. As compared with the case of the prior art apparatus, therefore, the same effect may be obtained with use of a smaller number of longer wickless heat pipes, which leads to a reduction in cost.
Since the fans 54 and 66 can enjoy increased setting space, large-sized fans can be used for them. Thus, the same amount of air flow may be provided by lower-speed operation, so that noise performance can be improved. Owing to the coaxial arrangement, moreover, the two fans 54 and 66 can share in common a single motor as their driving source, which, along with the simplified structure of coupling means, leads to simplification of the apparatus in construction.
According to this embodiment, furthermore, the cooling apparatus 42 is mounted on the top of the housing 40 so that the heat pipes 70 thereof are inclined at an angle of approximately 10° to the horizontal plane. Accordingly, the overall height of the cooling apparatus can be reduced as compared with the case where the heat pipes are erected upright on the top of the housing. Namely, the restrictions on the setting space can be reduced. If arranged horizontally, the heat pipes of the cooling apparatus need be of a wick-type which costs high. According to the embodiment, however, the inclination of the heat pipes 70 enables the refrigerant, after condensation, to return to the evaporating section by its own weight. Thus, it is possible to use the cheap wickless-type heat pipes without suffering high cost.
Since the motor 68 is disposed in the radiating chamber 50, moreover, the interior of the housing 40 will never be heated by heat generated at the drive of the motor 68.
It is to be understood that this invention is not limited to the construction of the above-mentioned embodiment, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.
For example, the series of heat pipes of the heat exchanger, which are arranged in a single layer in the above embodiment, may be arranged in a plurality of layers. With such alternative arrangement, the cooling efficiency may additionally be improved.
Further, the angle of inclination of the heat pipes need not always be approximately 10°. The desired effect may be obtained with use of any angle within a range from 5° to 15°.
Instead of using the common motor 68 for simultaneously driving the two sirocco fans 58 and 66, furthermore, the fans 58 and 66 may be fitted with their respective motors. | A cooling apparatus for a housing which is provided with an opening at the upper part thereof, comprises a casing located on the upper part of the housing and including a bottom plate to close the opening and a chamber, a partition wall provided in the casing to divide the chamber into a first chamber section and a second chamber section, heat exchanger including at least one heat pipe provided in the casing through the partition wall with coolant therein for exchanging heat in the first chamber section with heat in the second chamber section. The heat pipe has one end portion in the first chamber section and the other end portion in the second chamber section, and inclines with the one end portion located lower than the other end portion. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application Ser. No. 62/161,101, filed on May 13, 2015, entitled “ROBOTIC TOOL INTERCHANGE SYSTEM,” assigned to the assignee hereof, and expressly incorporated by reference herein.
FIELD
[0002] The present disclosure is directed to robotic tool systems and, more specifically, to a tool interchange system that may mount a tool to a robotic platform for remote use.
BACKGROUND
[0003] Both military and civilian police and security personnel can encounter situations in which it is desirable to remotely inspect or handle dangerous or potentially dangerous items. For example, it may be desirable to inspect, handle, or work on objects in locations where it is not possible, or not desirable, to send a person. Remotely operated devices, such as remotely operated robots or unmanned ground vehicles (UGVs) may be used in such situations. Throughout this disclosure, reference is made to a system for use with an unmanned ground vehicle (UGV). The terms UGV and robot are used interchangeably herein, with the understanding that such a platform is one example in which a system of this disclosure may be used, and that the disclosed systems have broad applicability for use in other and different platforms.
[0004] UGVs commonly include an arm that has a gripper assembly, and a camera mounted on the arm or on the UGV platform itself. An operator located a safe distance away operates the UGV using a video feed from the camera to inspect or work on an object, using the arm and gripper assembly to move or otherwise access the item. In many cases the arm, as mentioned, has a gripper that may be used to grasp and rotate an object. In some situations, the gripper may hold another tool that may be useful in a particular situation, such as a probe for probing soil that may be used to cover a control line that could be used to detonate an explosive device. However, in many situations, it may be desirable to have another type of tool mounted to the arm. Such may be the case when a gripper assembly, or a tool held by the gripper assembly, would not be the most advantageous tool for a particular situation. For example, it may be desired to have a probe in some situations, and a cutting tool in other situations. Equipping a robotic arm with a different tool generally takes some time, which may not be desirable during high-stress and time-sensitive operations such as deactivation of explosive ordnance for example. Furthermore, in some cases an operator may not know the optimum tool for a particular job until an UGV is actually adjacent to the object of interest. Additionally, a UGV may be subjected to relatively harsh conditions, including exposure to wind, rain, dirt, sand, and high or low temperatures, to name a few. Thus, it also would be desirable for any tool system to be robust against exposure to various different elements. Accordingly, providing options to an operator of such a remotely operated device would be beneficial.
SUMMARY
[0005] The present disclosure recognizes it would be useful to have a system in which a remotely operated device may have a library of available tools that may be selected by an operator. It would be advantageous to have such a system that is easily adaptable to allow the relatively fast exchange of different tools and that is straightforward to use. The present disclosure provides a Gripper Remote Tool Change System (GRTCS) which provides a locking guided tool changer assembly that interfaces with multiple tools, locks onto a tool holder, and is easily recognizable by a robot's gripper camera. According to various aspects, the present disclosure provides an intermediate solution for remote tool changing. A user does not need to physically interact with the robot and can accomplish the tool changing remotely. The GRTCS is a completely mechanical product and does not require altering the electronics on the base robotic platform to which it may be attached.
[0006] In some examples, a locking tool system is provided that interfaces with robotic grippers to allow robotic platforms to securely carry tools and swap between tools remotely. The locking tool system may include a modular tool holding system designed to integrate with robotic grippers. The system, in some examples, includes a collet, collet key, gripper guide, spring, and plunger key. The locking tool system may integrate with tool holders that are mounted to the robotic platform. The system can be used with a variety of tool types through the use of a spring pin, screw, or other securement mechanism.
[0007] In some aspects, a plunger key is integrated with tool holders on the robot's platform. The tool can be placed on the tool holder by engaging the plunger key. Engagement of the plunger key allows the tool to slide onto the tool holder and, to lock into place, the plunger key must disengage. To remove a tool, the operator may manipulate the gripper to close onto the gripper guide. Closing the gripper on the gripper guide engages the collet key to allow removal of the tool from the tool holder. Thus, various aspects of the disclosure provide a novel locking guided tool changer assembly that securely and robustly engages with a tool holder.
[0008] The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the spirit and scope of the appended claims. Features which are believed to be characteristic of the concepts disclosed herein, both as to their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description only, and not as a definition of the limits of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective and exploded view of a tool holder assembly according to various aspects of the present disclosure;
[0010] FIG. 2 is a perspective and exploded view of a locking guided tool changer assembly according to various aspects of the present disclosure;
[0011] FIG. 3 is section view of the locking guided tool changer mounted on tool holder according to various aspects of the present disclosure;
[0012] FIGS. 4A and 4B are perspective views of a locking guided tool changer according to various aspects of the present disclosure in engaged and disengaged configurations, respectively, according to various aspects of the present disclosure;
[0013] FIGS. 5A and 5B are perspective views of a locking guided tool changer according to various aspects of the present disclosure in engaged and disengaged configurations, respectively, rotated 90 degrees relative to the illustrations of FIG. 4 , according to various aspects of the present disclosure.
[0014] FIGS. 6A and 6B illustrate isometric views of another example of a locking guided tool changer assembly;
[0015] FIGS. 7A and 7B illustrate side cross section views of the locking guided tool changer assembly of FIG. 6 ;
[0016] FIGS. 8A and 8B illustrate views of the locking guided tool changer assembly of FIG. 6 ;
[0017] FIGS. 9A and 9B illustrate top cross section views of the locking guided tool changer assembly of FIG. 6 ; and
[0018] FIG. 10 shows an exploded view of the locking guided tool changer assembly of FIG. 6 .
DETAILED DESCRIPTION
[0019] This description provides examples, and is not intended to limit the scope, applicability or configuration of the invention. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing embodiments of the invention. Various changes may be made in the function and arrangement of elements.
[0020] Thus, various embodiments may omit, substitute, or add various procedures or components as appropriate. For instance, aspects and elements described with respect to certain embodiments may be combined in various other embodiments. It should also be appreciated that the following systems, devices, and components may individually or collectively be components of a larger system, wherein other procedures may take precedence over or otherwise modify their application.
[0021] The present disclosure is generally directed to systems and methods for mounting and using various different accessories on a robotic system such as a UGV. The present disclosure recognizes that UGVs commonly have features and characteristics that make easy and reliable tool change a challenge. For example, UGVs generally have low precision arms and controls which can result in unreliable arm placement at various preset positions. Furthermore, such arms commonly have significant amounts of flexibility and compliance. Additionally, the vehicle itself may not be level or particularly stable, further contributing to the low precision of movement of the arm. Thus, the present disclosure provides for reliable tool changing through simple engagement of the tool with the gripper assembly.
[0022] Additionally, it is beneficial for such vehicles to have failsafe conditions, such that tools are not dropped from the arm in the event of a power interruption. UGVs often also require operation in harsh environments with significant amounts of dirt, rocks, wind, moisture, and temperature extremes, to name a few. The present disclosure provides systems and methods for connection and operation of different tools to a UGV that provide efficient and reliable operations under such conditions.
[0023] With reference to FIG. 1 an example of a tool holder assembly 100 for use on a robot is illustrated, both in perspective view and an exploded view. For this discussion the term “tools” is meant to include a range of robotic manipulators, tools, sensors, or other devices that are utilized by the robot, all of which are referred to herein simply as “tools.” The tool holder assembly 100 may include a tool holder base stand 105 , a tool holder bracket support 110 , and a tool holder guide 115 , which may be coupled with one or more screws 120 or other securement components. One or more of such tool holders may be mounted on a robot, each having an associated tool, which may provide the robot with various tool options for use by an operator of the robot.
[0024] FIG. 2 illustrates perspective and exploded view of a locking guided tool changer assembly 200 according to various aspects of the present disclosure. The locking guide tool changer assembly 200 is configured to engage with the tool holder 100 of FIG. 1 , which may secure the tool holder 100 , and associated tool, securely until a gripper assembly engages with the locking guide tool changer 200 to release it from the tool holder 100 . The locking guide tool changer 200 includes a collet base assembly 205 , a collet key 215 , a key extender and spring 220 , a plunger key 220 , and a gripper guide assembly 225 , which may be secured together with screws 230 or other securement components, as illustrated in FIG. 2 . A tool may be attached to the collet base assembly 205 . The collet base assembly 205 may include channels 235 that may receive tool holder bracket support 110 and tool holder guide 115 , and the collet key 210 may engage with a detent of the tool holder bracket support 110 and tool holder guide 115 . FIG. 3 illustrates a section view of the locking guided tool changer 200 mounted on a tool holder 100 .
[0025] As mentioned, the locking guided tool changer 200 has a collet key 210 and collet base 205 that integrates with tool holders 100 on the robot's platform. The tool can be placed on the tool holder 100 by engaging the plunger key 220 , which may lock the locking guided tool changer 200 within a tool holder 100 . Engagement of the plunger key 220 allows the collet key 210 to be moved within collet base 205 , to lock or unlock the locking guided tool changer 200 and allow a tool mounted to the locking guided tool changer 200 to slide onto the tool holder 100 and lock in place. To remove a tool, the operator manipulates the robot's gripper to close onto the gripper guide assembly 225 . Closing the gripper on the gripper guide assembly 225 engages the plunger key 220 , moves the key extender 215 and collet key 210 within the collet base 205 to unlock the tool and allow removal of the tool from the tool holder 100 , through compression of a bushing and coil spring, to allow easy movement of the collet key 215 .
[0026] To remove the locking guided tool changer assembly 200 from the tool holder 100 , the gripper assembly of the robot may be maneuvered to exert pressure on the plunger key 220 toward the collet base 205 . This force will overcome the spring force holding the collet key 210 in the locked position. When the plunger key 220 is toward the tool holder 100 , and while holding this position, the locking guided tool changer assembly 200 can be removed from the tool holder 100 assembly. The operator of the robot may remove the locking guided tool changer assembly 200 by manipulating the robot's arm to lift the unit away from the tool holder 100 and a detent in the tool holder bracket support 110 and a tool holder guide 115 .
[0027] To place the locking guided tool changer assembly 200 back on the tool holder assembly 100 , an operator may manipulate the robot gripper assembly to press the plunger key 220 toward the collet 205 , and hold this position. The guide plate 115 of the tool holder assembly 100 may be used to help orientate the gripper in the correct position into the tool holder assembly 100 . The guide plate 115 also may be used to help with depth perception when needed, such as due to the camera being used to view the gripper assembly when an operator is performing this operation. The operator may then direct the locking guided tool changer assembly 200 with the point of the guide plate 115 toward the opening of the tool holder assembly 100 , and lower the locking guided tool changer assembly 200 into the tool holder assembly 100 . The operator may release the pressure on the plunger key 220 resulting in the key 220 moving up and locking the locking guided tool changer assembly 200 through engagement with the detents of the tool holder bracket support 110 and a tool holder guide 115 .
[0028] FIGS. 4A and 4B illustrate a locking guided tool changer assembly 200 according to various aspects of the present disclosure in engaged and disengaged configurations, respectively, and FIGS. 5A and 5B illustrate the locking guided tool changer assembly 200 rotated 90 degrees relative to the illustrations of FIG. 4 , in engaged and disengaged configurations, respectively.
[0029] The design of the gripper guide assembly, and plunger key may be modified to reflect the gripper geometry for particular robots, and the orientation of the collet base assembly can also be rotated as necessary to reflect the orientation of the mating robotic gripper. FIGS. 6-10 illustrate another example of a locking guided tool changer assembly 600 that may be configured for a different gripper geometry.
[0030] In the example of FIGS. 6-10 , the locking guided tool changer assembly 600 , as can be seen in the cross section views of FIGS. 7 and 9 , and the exploded view of FIG. 10 , includes a plunger 610 that may be actuated through mating surfaces 605 . When the mating surfaces 605 are moved inward (e.g., through squeezing of a robot gripper that engages a gripper guide 625 ) they push down the plunger 610 to move a collet key 615 relative to a collet base 620 and allow removal of the locking guided tool changer assembly 600 from a tool holder assembly 100 .
[0031] FIGS. 6A and 6B illustrate isometric views of the locking guided tool changer assembly 600 having the plunger not engaged ( FIG. 6A ) and engaged ( FIG. 6B ). FIGS. 7A and 7B illustrate side cross section views of the locking guided tool changer assembly 600 having the plunger not engaged ( FIG. 7A ) and engaged ( FIG. 7B ). FIGS. 8A and 8B illustrate isometric views of the locking guided tool changer assembly 600 having the plunger not engaged ( FIG. 8A ) and locked in tool holder assembly 100 , and having the plunger engaged ( FIG. 8B ) to unlock and allow movement of the locking guided tool changer assembly 600 from the tool holder assembly 100 . FIGS. 9A and 9B illustrate top cross section views of the locking guided tool changer assembly 600 having the plunger not engaged ( FIG. 9A ) and engaged ( FIG. 9B ). Finally, FIG. 10 shows an exploded view of the locking guided tool changer assembly 600 of this example.
[0032] While particular examples are described, it will be readily apparent to one of skill in the art that numerous variations may be implemented within the scope of this disclosure. For example, a shaft hole size in the collet may be resized for different tools, and a side hole of the collet may be changed to allow for a different spring pin, screw, or other securement mechanism for a tool. The plate guide of the tool holder assembly also may be changed to provide enhanced visual cues depending on the angle and orientation of the robot's camera. The plunger key could be altered to reflect the geometry of the gripper that the tool will interface with, and the gripper guide also may be changed to accommodate the gripper geometry. The compression value of the spring may be changed to alter the actuation force based on a particular robot. Additionally, the collet key geometry may be selected to match changes in the tool holder assembly that may be desirable for a particular application.
[0033] The embodiments illustrated in FIGS. 1-10 show a modular tool holder system according to aspects of the disclosure which may be mounted to a UGV robot. In the examples of FIGS. 1-10 , tool holder assemblies may be mounted to a library platform assembly, thereby providing a modular library system. Such a modular library provides the ability to reconfigure the number of tool holder stations and their positions on the library. This capability allows the deployment configuration of a robot to be modified to accommodate a specific number of tools, the types and sizes of the tools, and the weight of the overall system to enhance the functionality of the robotic system to meet specific mission requirements. For example, if five small tools are desired for the robot based on the expected requirements of a specific mission, the library can be configured with those specific tool holders. If a mission is expected to require the use of two small tools and one larger tool, the unused tool holders may be removed to accommodate the space requirements of the larger tool and to minimize the weight of the overall robotic UGV.
[0034] In one example, each individual tool holder is identical, and can be installed at any tool holder position on the library. This feature reduces workload for the human operator by eliminating the need to install a particular tool holder at a specific position on the library.
[0035] It should be noted that the systems and devices discussed above are intended merely to be examples. It must be stressed that various embodiments may omit, substitute, or add various procedures or components as appropriate. For instance, it should be appreciated that, in alternative embodiments, features described with respect to certain embodiments may be combined in various other embodiments. Different aspects and elements of the embodiments may be combined in a similar manner. Also, it should be emphasized that technology evolves and, thus, many of the elements are exemplary in nature and should not be interpreted to limit the scope of the invention.
[0036] Specific details are given in the description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. For example, well-known circuits, structures, and techniques have been shown without unnecessary detail in order to avoid obscuring the embodiments.
[0037] Having described several embodiments, it will be recognized by those of skill in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the invention. For example, the above elements may merely be a component of a larger system, wherein other rules may take precedence over or otherwise modify the application of the invention. Also, a number of steps may be undertaken before, during, or after the above elements are considered. Accordingly, the above description should not be taken as limiting the scope of the invention. | A Gripper Remote Tool Change System (GRTCS) provides a locking guided tool changer assembly that interfaces with multiple tools, locks onto a tool holder, and is easily recognizable by a robot's gripper camera. The GRTCS provides an intermediate solution for remote tool changing that does not require a user to physically interact with the robot to change a tool. The GRTCS may be a completely mechanical product that does not require altering the electronics on the base robotic platform to which it may be attached. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to printed circuit board connectors and, more particularly, to a printed circuit board connector having an integral ground plane.
A large number of multi-terminal high density connectors have been developed over the years for use in interconnecting multiple printed circuit boards. Many of these connectors have proven successful in interconnecting circuits carrying high level, low frequency signals. However, such connectors have generally been found to provide unacceptable performance in instances where the signals to be carried are either very low in amplitude or high in frequency.
One shortcoming of the prior art connectors of the type described above is the inability to provide a ground plane suitable for shielding between circuits. Such shielding is necessary to minimize both noise and cross coupling in circuits employing low amplitude or high frequency signals.
Accordingly, it is an object of the present invention to provide a new and improved printed circuit board connector.
It is another objective of the present invention to provide a new printed circuit board connector suitable for use with low amplitude and high frequency signals.
It is yet another objective of the present invention to provide a multi-terminal printed circuit board connector having an integral ground plane.
SUMMARY OF THE INVENTION
The foregoing and other objects of the invention are accomplished by a connector having a generally bar-shaped body formed of an insulating material. A thin sheet of conductive material is used to form the ground plane and has a central portion extending along the length of and affixed within the body. The thin sheet includes first and second pluralities of spaced-apart finger-like resilient projections which extend through the body from opposite sides of the central portion. The first and second pluralities of projections are bent across first and second opposing sides, respectively, of the body, where the length of, and the direction of bend of each of the projections is made in accordance with a predetermined ground plane pattern.
A plurality of resilient electrically conductive contacts are spaced apart in two rows along the length of the body, the rows being parallel to and on opposing sides of the central portion of the conductive sheet. Each contact has a central portion affixed within the body and first and second free ends extending from the first and second sides, respectively of the body. Each free end is bent across the respective side of the body in a direction toward the sheet of conductive material so that when a particular free end is pressed toward its respective side, a portion of that free end is forced into contact with an adjacent one of the finger-like projections if that adjacent projection is bent toward the particular free end.
A novel method of making the connector of the present invention includes the steps of molding a row of contacts into each of separate halves of the bar-shaped body. The ground plane is formed of the above described conductive sheet having the finger-like projections formed in accordance with the predetermined ground plane pattern. The connector is assembled by sandwiching the central portion of the conductive sheet between the two halves of the body and then bending the free ends of the contacts toward each other over the ground plane projection.
Other features, objects, and advantages of the invention will become apparent from a reading of the specification when taken in conjunction with the drawings in which like reference numerals refer to like elements in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a connector constructed in accordance with the present invention;
FIG. 2 is a side view of the connector of FIG. 1;
FIG. 3 is a side view showing the connector of FIG. 1 fastened between two printed circuit boards in a typical application of providing interconnections between these boards;
FIG. 4 is a top view of a portion of one of the circuit boards of FIG. 3 showing the position of printed circuit pads used to make connections with the connector of FIG. 1;
FIG. 5 is a cross-sectional side view of the connector of FIG. 1 taken along the line 5--5 of FIG. 2;
FIG. 6 is a front view of a conductive sheet for use as a typical ground plane in the connector of FIG. 1; and
FIG. 7 is a fragmented top view of the connector of FIG. 1 constructed using the ground plane of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 are top and side views, respectively, of the connector 10 of the present invention. The connector 10 includes a generally bar-shaped body 12 composed of two halves 14 and 16, each formed of a moldable insulating material such as Valox plastic, manufacutred by General Electric Company.
Embedded in each of the halves 14 and 16 is a row of spaced-apart, resilient, electrically conductive contact elements 18 formed of a material such as copper alloy. As shown in the cross-sectional view of FIG. 5, the central portion of each of the elements 18 is molded within the respective body half 14 and 16. First and second free ends 20 and 22 of each of the elements 18 project from opposing surfaces 24 and 26, respectively, of the body 12, and are bent at an angle across these surfaces and toward each other.
The connector 10 described thus far may be used as shown in FIG. 3 to interconnect two printed circuit boards 28 and 30 in the following manner. Each of the boards 28 and 30 includes a pattern consisting of two rows of contact pads 36 located between openings 38, as shown in FIG. 4. Generally circular hollow bosses 32 extend from shoulders 34 on opposite ends of the connector 10, as shown in FIG. 2. The bosses 32 are designed to fit into respective openings 38 in the boards 28 and 30. Bolts 40 extend through openings 38 and bosses 32 and are fastened with nuts 42, whereby the boards 28 and 30 are held against the shoulders 34 of the connector 10. In this position, the pads 36 on the surface of the boards 28 and 30 depress the resilient contact ends 20 and 22, respectively, thus establishing electrical connections between these boards through contacts 18. Raised barriers 44 positioned between selected contacts 18 project above the surfaces 24 and 26 at the same height as the shoulders 34. These barriers 44 help to maintain the surface of the boards 28 and 30 parallel to the surfaces 24 and 26 of the connector 10 and also serve to align the free ends 20 and 22 of the contacts 18.
The connector 10 is provided with an integral ground plane in the following manner. Referring to FIG. 6, a thin sheet 46 of a resilient conductive material, such as a copper alloy, is formed having a central portion 48 from which extends a pattern of finger-like projections 50. The projections 50 are spaced apart along the length of the sheet 46 corresponding to the spacing of the contacts 18 in the connector 10. The long projections, designated 52 in FIG. 6, are designed to contact particular ones of the free ends 20 and 22 of the contacts 18 to connect these ends to the common ground plane 46. For those projections 50 corresponding to contacts 18 where no grounding is required, the projections 50 are cut short at line 54. The long projections 52 are bent approximately perpendicular to the portion 48 along a line colinear with the line 54, where the direction of bend of each projection 52 depends on the particular free end to be grounded, as described below
Referring to the cross-sectional view of the connector 10 shown in FIG. 5, the central portion 48 of the cut and bent sheet 46 is sandwiched between the connector halves 14 and 16. The entire assembly is then fastened together using either adhesive, ultrasonic welding or other fastening technique well known to those skilled in the art. As shown in FIG. 5, in the completed assembly the previously bent projections 52 extend across the surfaces 24 and 26 and between those surfaces and the bent free ends 20 and 22, respectively, of the contacts 18.
FIG. 7 is a fragmented top view of the assembled connector showing the positions of the projections 52 relative to the free ends 20 of the contacts 18. The three projections 52 shown in the upper left portion of the sheet 46 of FIG. 6 are shown bent underneath alternating free ends 20 in connector half 14, where the ends 54 of the shortened projections 50 are approximately flush to the surfaces 24 and 26. The two projections 52 shown in the lower left portion of the sheet 46 of FIG. 6 (designated with dotted lead lines in FIG. 7) are bent downward underneath alternating free ends 22 adjacent the bottom surface 26 of the connector half 16.
As described above, when the connector 10 is assembled between the two printed circuit boards 28 and 30, the resilient free ends 29 and 22 are pressed toward the surfaces 24 and 26, respectively. Referring to FIG. 5, the free ends designated 20' and shown in dashed lines indicate the depressed positions of the ends 20. The ends 22 are similarly depressed toward the surface 26. It may be seen that when the ends 20 and 22 are depressed, they are forced into contact with adjacent projections 52. The projections 52 are provided with pointed ends to increase the contact pressure between them and the respective free ends 20 and 22.
It will be appreciated that when a free end 20 or 22 is pressed into contact with a projection 52, the corresponding contact 18 is electrically connected in common with the conductive sheet 46. The pattern of the projections 52 of the sheet 46 determines which of the contacts 18 will be grounded. Accordingly, any one of a multitude of contact grounding patterns may be provided in the connector 10 simply by cutting and bending the sheet 46 in the appropriate manner. By way of example, the top view of FIG. 1 shows a ground plane pattern in which every fourth contact 18 in the connector half 16 is grounded by projections 52 contacting appropriate free ends 20. From cross-sectional view of FIG. 5, it may be seen that the placement of the central portion 48 of the sheet 46 between opposite rows of contacts 18 causes the portion 48 to act as a shield between these two rows, further enhancing the high frequency characteristics of the connector 10.
While there has been shown and described a preferred embodiment of the invention, it is to be understood that various other adaptations and modifications may be made within the spirit and scope of the invention. It is thus intended that the invention be limited in scope only by the appended claims. | A connector with an integral ground plane for making connections between two circuit boards is disclosed in which the connector has a bar-shaped body including generally C-shaped contacts extending in a row on opposite sides of the body. A ground plane in the form of a thin conductive sheet is positioned in the body between the rows, and has a predetermined pattern of projections which are bent to contact specific ones of the C-shaped contacts when the connector is assembled between the two circuit boards. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 10/743,451, filed Dec. 19, 2003, now abandoned, which is a continuation of U.S. patent application Ser. No. 10/348,231, filed Jan. 21, 2003, now U.S. Pat. No. 7,009,040, issued Mar. 7, 2006, and is also a continuation-in-part of U.S. patent application Ser. No. 10/891,866, filed Jul. 15, 2004, now U.S. Pat. No. 7,186,808, issued Mar. 6, 2007, which is a divisional of U.S. patent application Ser. No. 10/348,231, filed Jan. 21, 2003, now U.S. Pat. No. 7,009,040, issued Mar. 7, 2006, the contents of which are herein incorporated by reference
FIELD OF THE INVENTION
This invention relates to the isolation and production of cancerous disease modifying antibodies (CDMAB) and to the use of these CDMAB in therapeutic and diagnostic processes, optionally in combination with one or more chemotherapeutic agents. The invention further relates to binding assays which utilize the CDMABs of the instant invention.
BACKGROUND OF THE INVENTION
Each individual who presents with cancer is unique and has a cancer that is as different from other cancers as that person's identity. Despite this, current therapy treats all patients with the same type of cancer, at the same stage, in the same way. At least 30% of these patients will fail the first line therapy, thus leading to further rounds of treatment and the increased probability of treatment failure, metastases, and ultimately, death. A superior approach to treatment would be the customization of therapy for the particular individual. The only current therapy which lends itself to customization is surgery. Chemotherapy and radiation treatment can not be tailored to the patient, and surgery by itself, in most cases is inadequate for producing cures.
With the advent of monoclonal antibodies, the possibility of developing methods for customized therapy became more realistic since each antibody can be directed to a single epitope. Furthermore, it is possible to produce a combination of antibodies that are directed to the constellation of epitopes that uniquely define a particular individual's tumor.
Having recognized that a significant difference between cancerous and normal cells is that cancerous cells contain antigens that are specific to transformed cells, the scientific community has long held that monoclonal antibodies can be designed to specifically target transformed cells by binding specifically to these cancer antigens; thus giving rise to the belief that monoclonal antibodies can serve as “Magic Bullets” to eliminate cancer cells.
Monoclonal antibodies isolated in accordance with the teachings of the instantly disclosed invention have been shown to modify the cancerous disease process in a manner which is beneficial to the patient, for example by reducing the tumor burden, and will variously be referred to herein as cancerous disease modifying antibodies (CDMAB) or “anti-cancer” antibodies.
At the present time, the cancer patient usually has few options of treatment. The regimented approach to cancer therapy has produced improvements in global survival and morbidity rates. However, to the particular individual, these improved statistics do not necessarily correlate with an improvement in their personal situation.
Thus, if a methodology was put forth which enabled the practitioner to treat each tumor independently of other patients in the same cohort, this would permit the unique approach of tailoring therapy to just that one person. Such a course of therapy would, ideally, increase the rate of cures, and produce better outcomes, thereby satisfying a long-felt need.
Historically, the use of polyclonal antibodies has been used with limited success in the treatment of human cancers. Lymphomas and leukemias have been treated with human plasma, but there were few prolonged remission or responses. Furthermore, there was a lack of reproducibility and there was no additional benefit compared to chemotherapy. Solid tumors such as breast cancers, melanomas and renal cell carcinomas have also been treated with human blood, chimpanzee serum, human plasma and horse serum with correspondingly unpredictable and ineffective results.
There have been many clinical trials of monoclonal antibodies for solid tumors. In the 1980s there were at least four clinical trials for human breast cancer which produced only one responder from at least 47 patients using antibodies against specific antigens or based on tissue selectivity. It was not until 1998 that there was a successful clinical trial using a humanized anti-her 2 antibody in combination with Cisplatin. In this trial 37 patients were accessed for responses of which about a quarter had a partial response rate and another half had minor or stable disease progression.
The clinical trials investigating colorectal cancer involve antibodies against both glycoprotein and glycolipid targets. Antibodies such as 17-1A, which has some specificity for adenocarcinomas, had undergone Phase 2 clinical trials in over 60 patients with only one patient having a partial response. In other trials, use of 17-1A produced only one complete response and two minor responses among 52 patients in protocols using additional cyclophosphamide. Other trials involving 17-1A yielded results that were similar. The use of a humanized murine monoclonal antibody initially approved for imaging also did not produce tumor regression. To date there has not been an antibody that has been effective for colorectal cancer. Likewise there have been equally poor results for lung cancer, brain cancers, ovarian cancers, pancreatic cancer, prostate cancer, and stomach cancer. There has been some limited success in the use of anti-GD3 monoclonal antibody for melanoma. Thus, it can be seen that despite successful small animal studies that are a prerequisite for human clinical trials, the antibodies that have been tested have been for the most part ineffective.
Prior Patents:
U.S. Pat. No. 5,750,102 discloses a process wherein cells from a patient's tumor are transfected with MHC genes which may be cloned from cells or tissue from the patient. These transfected cells are then used to vaccinate the patient.
U.S. Pat. No. 4,861,581 discloses a process comprising the steps of obtaining monoclonal antibodies that are specific to an internal cellular component of neoplastic and normal cells of the mammal but not to external components, labeling the monoclonal antibody, contacting the labeled antibody with tissue of a mammal that has received therapy to kill neoplastic cells, and determining the effectiveness of therapy by measuring the binding of the labeled antibody to the internal cellular component of the degenerating neoplastic cells. In preparing antibodies directed to human intracellular antigens, the patentee recognizes that malignant cells represent a convenient source of such antigens.
U.S. Pat. No. 5,171,665 provides a novel antibody and method for its production. Specifically, the patent teaches formation of a monoclonal antibody which has the property of binding strongly to a protein antigen associated with human tumors, e.g. those of the colon and lung, while binding to normal cells to a much lesser degree.
U.S. Pat. No. 5,484,596 provides a method of cancer therapy comprising surgically removing tumor tissue from a human cancer patient, treating the tumor tissue to obtain tumor cells, irradiating the tumor cells to be viable but non-tumorigenic, and using these cells to prepare a vaccine for the patient capable of inhibiting recurrence of the primary tumor while simultaneously inhibiting metastases. The patent teaches the development of monoclonal antibodies which are reactive with surface antigens of tumor cells. As set forth at col. 4, lines 45 et seq., the patentees utilize autochthonous tumor cells in the development of monoclonal antibodies expressing active specific immunotherapy in human neoplasia.
U.S. Pat. No. 5,693,763 teaches a glycoprotein antigen characteristic of human carcinomas and not dependent upon the epithelial tissue of origin.
U.S. Pat. No. 5,783,186 is drawn to Anti-Her2 antibodies which induce apoptosis in Her2 expressing cells, hybridoma cell lines producing the antibodies, methods of treating cancer using the antibodies and pharmaceutical compositions including said antibodies.
U.S. Pat. No. 5,849,876 describes new hybridoma cell lines for the production of monoclonal antibodies to mucin antigens purified from tumor and non-tumor tissue sources.
U.S. Pat. No. 5,869,268 is drawn to a method for generating a human lymphocyte producing an antibody specific to a desired antigen, a method for producing a monoclonal antibody, as well as monoclonal antibodies produced by the method. The patent is particularly drawn to the production of an anti-HD human monoclonal antibody useful for the diagnosis and treatment of cancers.
U.S. Pat. No. 5,869,045 relates to antibodies, antibody fragments, antibody conjugates and single chain immunotoxins reactive with human carcinoma cells. The mechanism by which these antibodies function is two-fold, in that the molecules are reactive with cell membrane antigens present on the surface of human carcinomas, and further in that the antibodies have the ability to internalize within the carcinoma cells, subsequent to binding, making them especially useful for forming antibody-drug and antibody-toxin conjugates. In their unmodified form the antibodies also manifest cytotoxic properties at specific concentrations.
U.S. Pat. No. 5,780,033 discloses the use of autoantibodies for tumor therapy and prophylaxis. However, this antibody is an antinuclear autoantibody from an aged mammal. In this case, the autoantibody is said to be one type of natural antibody found in the immune system. Because the autoantibody comes from “an aged mammal”, there is no requirement that the autoantibody actually comes from the patient being treated. In addition the patent discloses natural and monoclonal antinuclear autoantibody from an aged mammal, and a hybridoma cell line producing a monoclonal antinuclear autoantibody.
SUMMARY OF THE INVENTION
The instant inventors have previously been awarded U.S. Pat. No. 6,180,357, entitled “Individualized Patient Specific Anti-Cancer Antibodies” directed to a process for selecting individually customized anti-cancer antibodies which are useful in treating a cancerous disease.
This application utilizes the method for producing patient specific anti-cancer antibodies as taught in the '357 patent for isolating hybridoma cell lines which encode for cancerous disease modifying monoclonal antibodies. These antibodies can be made specifically for one tumor and thus make possible the customization of cancer therapy. Within the context of this application, anti-cancer antibodies having either cell-killing (cytotoxic) or cell-growth inhibiting (cytostatic) properties will hereafter be referred to as cytotoxic. These antibodies can be used in aid of staging and diagnosis of a cancer, and can be used to treat tumor metastases.
The prospect of individualized anti-cancer treatment will bring about a change in the way a patient is managed. A likely clinical scenario is that a tumor sample is obtained at the time of presentation, and banked. From this sample, the tumor can be typed from a panel of pre-existing cancerous disease modifying antibodies. The patient will be conventionally staged but the available antibodies can be of use in further staging the patient. The patient can be treated immediately with the existing antibodies, and a panel of antibodies specific to the tumor can be produced either using the methods outlined herein or through the use of phage display libraries in conjunction with the screening methods herein disclosed. All the antibodies generated will be added to the library of anti-cancer antibodies since there is a possibility that other tumors can bear some of the same epitopes as the one that is being treated. The antibodies produced according to this method may be useful to treat cancerous disease in any number of patients who have cancers that bind to these antibodies.
In addition to anti-cancer antibodies, the patient can elect to receive the currently recommended therapies as part of a multi-modal regimen of treatment. The fact that the antibodies isolated via the present methodology are relatively non-toxic to non-cancerous cells allows for combinations of antibodies at high doses to be used, either alone, or in conjunction with conventional therapy. The high therapeutic index will also permit re-treatment on a short time scale that should decrease the likelihood of emergence of treatment resistant cells.
Furthermore, it is within the purview of this invention to conjugate standard chemotherapeutic modalities, e.g. radionuclides, with the CDMABs of the instant invention, thereby focusing the use of said chemotherapeutics.
If the patient is refractory to the initial course of therapy or metastases develop, the process of generating specific antibodies to the tumor can be repeated for re-treatment. Furthermore, the anti-cancer antibodies can be conjugated to red blood cells obtained from that patient and re-infused for treatment of metastases. There have been few effective treatments for metastatic cancer and metastases usually portend a poor outcome resulting in death. However, metastatic cancers are usually well vascularized and the delivery of anti-cancer antibodies by red blood cells can have the effect of concentrating the antibodies at the site of the tumor. Even prior to metastases, most cancer cells are dependent on the host's blood supply for their survival and anti-cancer antibody conjugated to red blood cells can be effective against in situ tumors as well. Alternatively, the antibodies may be conjugated to other hematogenous cells, e.g. lymphocytes, macrophages, monocytes, natural killer cells, etc.
There are five classes of antibodies and each is associated with a function that is conferred by its heavy chain. It is generally thought that cancer cell killing by naked antibodies are mediated either through antibody dependent cellular cytotoxicity or complement dependent cytotoxicity. For example murine IgM and IgG2a antibodies can activate human complement by binding the C-1 component of the complement system thereby activating the classical pathway of complement activation which can lead to tumor lysis. For human antibodies the most effective complement activating antibodies are generally IgM and IgG 1. Murine antibodies of the IgG2a and IgG3 isotype are effective at recruiting cytotoxic cells that have Fc receptors which will lead to cell killing by monocytes, macrophages, granulocytes and certain lymphocytes. Human antibodies of both the IgG1 and IgG3 isotype mediate ADCC.
Another possible mechanism of antibody mediated cancer killing may be through the use of antibodies that function to catalyze the hydrolysis of various chemical bonds in the cell membrane and its associated glycoproteins or glycolipids, so-called catalytic antibodies.
There are two additional mechanisms of antibody mediated cancer cell killing which are more widely accepted. The first is the use of antibodies as a vaccine to induce the body to produce an immune response against the putative cancer antigen that resides on the tumor cell. The second is the use of antibodies to target growth receptors and interfere with their function or to down regulate that receptor so that effectively its function is lost.
Accordingly, it is an objective of the invention to utilize a method for producing cancerous disease modifying antibodies from cells derived from a particular individual which are cytotoxic with respect to cancer cells while simultaneously being relatively non-toxic to non-cancerous cells, in order to isolate hybridoma cell lines and the corresponding isolated monoclonal antibodies and antigen binding fragments thereof for which said hybridoma cell lines are encoded.
It is an additional objective of the invention to teach cancerous disease modifying antibodies and antigen binding fragments thereof.
It is a further objective of the instant invention to produce cancerous disease modifying antibodies whose cytotoxicity is mediated through antibody dependent cellular toxicity.
It is yet an additional objective of the instant invention to produce cancerous disease modifying antibodies whose cytotoxicity is mediated through complement dependent cellular toxicity.
It is still a further objective of the instant invention to produce cancerous disease modifying antibodies whose cytotoxicity is a function of their ability to catalyze hydrolysis of cellular chemical bonds.
A still further objective of the instant invention is to produce cancerous disease modifying antibodies which are useful for in a binding assay for diagnosis, prognosis, and monitoring of cancer.
Other objects and advantages of this invention will become apparent from the following description wherein are set forth, by way of illustration and example, certain embodiments of this invention.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 includes representative FACS histograms of 1A245.6 antibodies, isotype control antibodies for both antibodies, anti-EGFR antibodies directed against several cancer cell lines and non-cancer cells;
FIG. 2 includes representative FACS histograms of 7BD-33-11A antibodies, isotype control antibodies for 1A245.6, anti-EGFR antibodies, isotype control antibodies for anti-EGFR directed against several cancer cell lines and non-cancer cells;
FIG. 3 includes representative FACS histograms of 11BD-2E11-2 antibodies, isotype control antibodies for both antibodies, anti-EGFR antibodies directed against several cancer cell lines and non-cancer cells;
FIG. 4 is a graphical analysis of tumor volume over time with respect to particular antibody treatment;
FIG. 5 is a graphical analysis of antibody effect on MB231 Human Breast Cancer tumor volume over time;
FIG. 6 is a graphical analysis quantifying percent survival over time relative to antibody therapy.
DETAILED DESCRIPTION OF THE INVENTION
In general, the following words or phrases have the indicated definition when used in the summary, description, examples, and claims.
The term “antibody” is used in the broadest sense and specifically covers, for example, single monoclonal antibodies (including agonist, antagonist, and neutralizing antibodies, de-immunized, murine, chimerized or humanized antibodies), antibody compositions with polyepitopic specificity, single chain antibodies, immunoconjugates and fragments of antibodies (see below).
The term “monoclonal antibody” as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical except for possible naturally occurring mutations that may be present in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. Furthermore, in contrast to polyclonal antibody preparations which include different antibodies directed against different determinants (epitopes), each monoclonal antibody is directed against a single determinant on the antigen. In addition to their specificity, the monoclonal antibodies are advantageous in that they may be synthesized uncontaminated by other antibodies. The modifier “monoclonal” indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and is not to be construed as requiring production of the antibody by any particular method. For example, the monoclonal antibodies to be used in accordance with the present invention may be made by the hybridoma (murine or human) method first described by Kohler et al., Nature, 256:495 (1975), or may be made by recombinant DNA methods (see, e.g., U.S. Pat. No. 4,816,567). The “monoclonal antibodies” may also be isolated from phage antibody libraries using the techniques described in Clackson et al., Nature, 352:624-628 (1991) and Marks et al., J. Mol. Biol., 222:581-597 (1991), for example.
“Antibody fragments” comprise a portion of an intact antibody, preferably comprising the antigen-binding or variable region thereof. Examples of antibody fragments include less than full length antibodies, Fab, Fab′, F(ab′) 2 , and Fv fragments; diabodies; linear antibodies; single-chain antibody molecules; single-chain antibodies, single domain antibody molecules, fusion proteins, recombinant proteins and multispecific antibodies formed from antibody fragment(s).
An “intact” antibody is one which comprises an antigen-binding variable region as well as a light chain constant domain (CL) and heavy chain constant domains, C H 1, C H 2 and C H 3. The constant domains may be native sequence constant domains (e.g. human native sequence constant domains) or amino acid sequence variant thereof. Preferably, the intact antibody has one or more effector functions.
Depending on the amino acid sequence of the constant domain of their heavy chains, intact antibodies can be assigned to different “classes”. There are five-major classes of intact antibodies: IgA, IgD, IgE, IgG, and IgM, and several of these may be further divided into “subclasses” (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA, and IgA2. The heavy-chain constant domains that correspond to the different classes of antibodies are called a, d, e, ?, and μ, respectively. The subunit structures and three-dimensional configurations of different classes of immunoglobulins are well known.
Antibody “effector functions” refer to those biological activities attributable to the Fc region (a native sequence Fc region or amino acid sequence variant Fc region) of an antibody. Examples of antibody effector functions include C1q binding; complement dependent cytotoxicity; Fc receptor binding; antibody-dependent cell-mediated cytotoxicity (ADCC); phagocytosis; down regulation of cell surface receptors (e.g. B cell receptor; BCR), etc.
“Antibody-dependent cell-mediated cytotoxicity” and “ADCC” refer to a cell-mediated reaction in which nonspecific cytotoxic cells that express Fc receptors (FcRs) (e.g. Natural Killer (NK) cells, neutrophils, and macrophages) recognize bound antibody on a target cell and subsequently cause lysis of the target cell. The primary cells for mediating ADCC, NK cells, express Fc?RIII only, whereas monocytes express Fc?RI, Fc?RII and Fc?RIII. FcR expression on hematopoietic cells in summarized is Table 3 on page 464 of Ravetch and Kinet, Annu. Rev. Immunol 9:457-92 (1991). To assess ADCC activity of a molecule of interest, an in vitro ADCC assay, such as that described in U.S. Pat. No. 5,500,362 or 5,821,337 may be performed. Useful effector cells for such assays include peripheral blood mononuclear cells (PBMC) and Natural Killer (NK) cells. Alternatively, or additionally, ADCC activity of the molecule of interest may be assessed in vivo, e.g., in a animal model such as that disclosed in Clynes et al. PNAS (USA) 95:652-656 (1998).
“Effector cells” are leukocytes which express one or more FcRs and perform effector functions. Preferably, the cells express at least Fc?RIII and perform ADCC effector function. Examples of human leukocytes which mediate ADCC include peripheral blood mononuclear cells (PBMC), natural killer (NK) cells, monocytes, cytotoxic T cells and neutrophils; with PBMCs and NK cells being preferred. The effector cells may be isolated from a native source thereof, e.g. from blood or PBMCs as described herein.
The terms “Fc receptor” or “FcR” are used to describe a receptor that binds to the Fe region of an antibody. The preferred FcR is a native sequence human FcR. Moreover, a preferred FcR is one which binds an IgG antibody (a gamma receptor) and includes receptors of the Fc?RI, Fc?RII, and Fc? RIII subclasses, including allelic variants and alternatively spliced forms of these receptors. Fc?RII receptors include Fc?RIIA (an “activating receptor”) and Fc?RIIB (an “inhibiting receptor”), which have similar amino acid sequences that differ primarily in the cytoplasmic domains thereof. Activating receptor Fc?RIIA contains an immunoreceptor tyrosine-based activation motif (ITAM) in its cytoplasmic domain. Inhibiting receptor Fc?RIIB contains an immunoreceptor tyrosine-based inhibition motif (ITIM) in its cytoplasmic domain. (see review M. in Daëron, Annu. Rev. Immunol. 15:203-234 (1997)). FcRs are reviewed in Ravetch and Kinet, Annu. Rev. Immunol 9:457-92 (1991); Capel et al., Immunomethods 4:25-34 (1994); and de Haas et al., J. Lab. Clin. Med. 126:330-41 (1995). Other FcRs, including those to be identified in the future, are encompassed by the term “FcR” herein. The term also includes the neonatal receptor, FcRn, which is responsible for the transfer of maternal IgGs to the fetus (Guyer et al., J. Immunol. 117:587 (1976) and Kim et al., Eur. J. Immunol. 24:2429 (1994)).
“Complement dependent cytotoxicity” or “CDC” refers to the ability of a molecule to lyse a target in the presence of complement. The complement activation pathway is initiated by the binding of the first component of the complement system (C1q) to a molecule (e.g. an antibody) complexed with a cognate antigen. To assess complement activation, a CDC assay, e.g. as described in Gazzano-Santoro et al., J. Immunol. Methods 202:163 (1996), may be performed.
The term “variable” refers to the fact that certain portions of the variable domains differ extensively in sequence among antibodies and are used in the binding and specificity of each particular antibody for its particular antigen. However, the variability is not evenly distributed throughout the variable domains of antibodies. It is concentrated in three segments called hypervariable regions both in the light chain and the heavy chain variable domains. The more highly conserved portions of variable domains are called the framework regions (FRs). The variable domains of native heavy and light chains each comprise four FRs, largely adopting a β-sheet configuration, connected by three hypervariable regions, which form loops connecting, and in some cases forming part of, the >sheet structure. The hypervariable regions in each chain are held together in close proximity by the FRs and, with the hypervariable regions from the other chain, contribute to the formation of the antigen-binding site of antibodies (see Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991)). The constant domains are not involved directly in binding an antibody to an antigen, but exhibit various effector functions, such as participation of the antibody in antibody dependent cellular cytotoxicity (ADCC).
The term “hypervariable region” when used herein refers to the amino acid residues of an antibody which are responsible for antigen-binding. The hypervariable region generally comprises amino acid residues from a “complementarity determining region” or “CDR” (e.g. residues 24-34 (L1), 50-56 (L2) and 89-97 (L3) in the light chain variable domain and 31-35 (H1), 50-65 (H2) and 95-102 (H3) in the heavy chain variable domain; Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991)) and/or those residues from a “hypervariable loop” (e.g. residues 2632 (L1), 50-52 (L2) and 91-96 (L3) in the light chain variable domain and 26-32 (H1), 53-55 (H2) and 96-101 (H3) in the heavy chain variable domain; Chothia and Lesk J. Mol. Biol. 196:901-917 (1987)). “Framework Region” or “FR” residues are those variable domain residues other than the hypervariable region residues as herein defined. Papain digestion of antibodies produces two identical antigen-binding fragments, called “Fab” fragments, each with a single antigen-binding site, and a residual “Fc” fragment, whose name reflects its ability to crystallize readily. Pepsin treatment yields an F(ab′) 2 fragment that has two antigen-binding sites and is still capable of cross-linking antigen.
“Fv” is the minimum antibody fragment which contains a complete antigen-recognition and antigen-binding site. This region consists of a dimer of one heavy chain and one light chain variable domain in tight, non-covalent association. It is in this configuration that the three hypervariable regions of each variable domain interact to define an antigen-binding site on the surface of the V H -V L dimer. Collectively, the six hypervariable regions confer antigen-binding specificity to the antibody. However, even a single variable domain (or half of an Fv comprising only three hypervariable regions specific for an antigen) has the ability to recognize and bind antigen, although at a lower affinity than the entire binding site. The Fab fragment also contains the constant domain of the light chain and the first constant domain (CH I) of the heavy chain. Fab′ fragments differ from Fab fragments by the addition of a few residues at the carboxy terminus of the heavy chain CH1 domain including one or more cysteines from the antibody hinge region. Fab′-SH is the designation herein for Fab′ in which the cysteine residue(s) of the constant domains bear at least one free thiol group. F(ab′) 2 antibody fragments originally were produced as pairs of Fab′ fragments which have hinge cysteines between them. Other chemical couplings of antibody fragments are also known.
The “light chains” of antibodies from any vertebrate species can be assigned to one of two clearly distinct types, called kappa (?) and lambda (?), based on the amino acid sequences of their constant domains.
“Single-chain Fv” or “scFv” antibody fragments comprise the V H and V L domains of antibody, wherein these domains are present in a single polypeptide chain. Preferably, the Fv polypeptide further comprises a polypeptide linker between the V H and V L domains which enables the scFv to form the desired structure for antigen binding. For a review of scFv see Plückthun in The Pharmacology of Monoclonal Antibodies , vol. 113, Rosenburg and Moore eds., Springer-Verlag, New York, pp. 269-315 (1994).
The term “diabodies” refers to small antibody fragments with two antigen-binding sites, which fragments comprise a variable heavy domain (V H ) connected to a variable light domain (V L ) in the same polypeptide chain (V H -V L ). By using a linker that is too short to allow pairing between the two domains on the same chain, the domains are forced to pair with the complementary domains of another chain and create two antigen-binding sites. Diabodies are described more fully in, for example, EP 404,097; WO 93/11161; and Hollinger et al., Proc. Natl. Acad. Sci. USA, 90:6444-6448 (1993).
An “isolated” antibody is one which has been identified and separated and/or recovered from a component of its natural environment. Contaminant components of its natural environment are materials which would interfere with diagnostic or therapeutic uses for the antibody, and may include enzymes, hormones, and other protcinaceous or nonproteinaceous solutes. Isolated antibody includes the antibody in situ within recombinant cells since at least one component of the antibody's natural environment will not be present. Ordinarily, however, isolated antibody will be prepared by at least one purification step.
An antibody “which binds” an antigen of interest is one capable of binding that antigen with sufficient affinity such that the antibody is useful as a therapeutic or diagnostic agent in targeting a cell expressing the antigen. Where the antibody is one which binds a particular antigenic moiety it will usually preferentially bind that antigenic moiety as opposed to other receptors, and does not include incidental binding such as non-specific Fc contact, or binding to post-translational modifications common to other antigens and may be one which does not significantly cross-react with other proteins. Methods, for the detection of an antibody that binds an antigen of interest, are well known in the art and can include but are not limited to assays such as FACS, cell ELISA and Western blot.
As used herein, the expressions “cell”, “cell line”, and “cell culture” are used interchangeably, and all such designations include progeny. It is also understood that all progeny may not be precisely identical in DNA content, due to deliberate or inadvertent mutations. Mutant progeny that have the same function or biological activity as screened for in the originally transformed cell are included. It will be clear from the context where distinct designations are intended.
“Treatment” refers to both therapeutic treatment and prophylactic or preventative measures, wherein the object is to prevent or slow down (lessen) the targeted pathologic condition or disorder. Those in need of treatment include those already with the disorder as well as those prone to have the disorder or those in whom the disorder is to be prevented. Hence, the mammal to be treated herein may have been diagnosed as having the disorder or may be predisposed or susceptible to the disorder.
The terms “cancer” and “cancerous” refer to or describe the physiological condition in mammals that is typically characterized by unregulated cell growth or death. Examples of cancer include, but are not limited to, carcinoma, lymphoma, blastoma, sarcoma, and leukemia or lymphoid malignancies. More particular examples of such cancers include squamous cell cancer (e.g. epithelial squamous cell cancer), lung cancer including small-cell lung cancer, non-small cell lung cancer, adenocarcinoma of the lung and squamous carcinoma of the lung, cancer of the peritoneum, hepatocellular cancer, gastric or stomach cancer including gastrointestinal cancer, pancreatic cancer, glioblastoma, cervical cancer, ovarian cancer, liver cancer, bladder cancer, hepatoma, breast cancer, colon cancer, rectal cancer, colorectal cancer, endometrial or uterine carcinoma, salivary gland carcinoma, kidney or renal cancer, prostate cancer, vulval cancer, thyroid cancer, hepatic carcinoma, anal carcinoma, penile carcinoma, as well as head and neck cancer.
A “chemotherapeutic agent” is a chemical compound useful in the treatment of cancer. Examples of chemotherapeutic agents include alkylating agents such as thiotepa and cyclosphosphamide (CYTOXAN™); alkyl sulfonates such as busulfan, improsulfan and piposulfan; aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, trietylenephosphoramide, triethylenethiophosphaoramide and trimethylolomelamine; nitrogen mustards such as chlorambucil, chlomaphazine, cholophosphamide, estramustine, ifosfamide, mechlorethamine, mechlorethamine oxide hydrochloride, melphalan, novembichin, phenesterine, prednimustine, trofosfamide, uracil mustard; nitrosureas such as carmustine, chlorozotocin, fotemustine, lomustine, nimustine, ranimustine; antibiotics such as aclacinomysins, actinomycin, authramycin, azaserine, bleomycins, cactinomycin, calicheamicin, carabicin, camomycin, carzinophilin, chromomycins, dactinomycin, daunorubicin, detorubicin, 6-diazo-5-oxo-L-norleucine, doxorubicin, epirubicin, esorubicin, idarubicin, marcellomycin, mitomycins, mycophenolic acid, nogalamycin, olivomycins, peplomycin, potfiromycin, puromycin, quelamycin, rodorubicin, streptonigrin, streptozocin, tubercidin, ubenimex, zinostatin, zorubicin; anti-metabolites such as methotrexate and 5-fluorouracil (5-FU); folic acid analogues such as denopterin, methotrexate, pteropterin, trimetrexate; purine analogs such as fludarabine, 6-mercaptopurine, thiamiprine, thioguanine; pyrimidine analogs such as ancitabine, azacitidine, 6-azauridine, carmofur, cytarabine, dideoxyuridine, doxifluridine, enocitabine, floxuridine, 5-FU; androgens such as calusterone, dromostanolone propionate, epitiostanol, mepitiostane, testolactone; anti-adrenals such as aminoglutethimide, mitotane, trilostane; folic acid replenisher such as frolinic acid; aceglatone; aldophosphamide glycoside; aminolevulinic acid; amsacrine; bestrabucil; bisantrene; edatraxate; defofamine; demecolcine; diaziquone; elformithine; elliptinium acetate; etoglucid; gallium nitrate; hydroxyurea; lentinan; lonidamine; mitoguazone; mitoxantrone; mopidamol; nitracrine; pentostatin; phenamet; pirarubicin; podophyllinic acid; 2-ethylhydrazide; procarbazine; PSK®; razoxane; sizofiran; spirogermanium; tenuazonic acid; triaziquone; 2,2′,2?-trichlorotriethylamine; urethan; vindesine; dacarbazine; mannomustine; mitobronitol; mitolactol; pipobroman; gacytosine; arabinoside (“Ara-C”); cyclophosphamide; thiotepa; taxanes, e.g. paclitaxel (TAXOL®, Bristol-Myers Squibb Oncology, Princeton, N.J.) and docetaxel (TAXOTERE®, Aventis, Rhone-Poulenc Rorer, Antony, France); chlorambucil; gemcitabine; 6-thioguanine; mercaptopurine; methotrexate; platinum analogs such as cisplatin and carboplatin; vinblastine; platinum; etoposide (VP-16); ifosfamide; mitomycin C; mitoxantrone; vincristine; vinorelbine; navelbine; novantrone; teniposide; daunomycin; aminopterin; xeloda; ibandronate; CPT-11; topoisomerase inhibitor RFS 2000; difluoromethylornithine (DMFO); retinoic acid; esperamicins; capecitabine; and pharmaceutically acceptable salts, acids or derivatives of any of the above. Also included in this definition are anti-hormonal agents that act to regulate or inhibit hormone action on tumors such as anti-estrogens including for example tamoxifen, raloxifene, aromatase inhibiting 4(5)-imidazoles, 4-hydroxytamoxifen, trioxifene, keoxifene, LY117018, onapristone, and toremifene (Fareston); and anti-androgens such as flutamide, nilutamide, bicalutamide, leuprolide, and goserelin; and pharmaceutically acceptable salts, acids or derivatives of any of the above.
“Mammal” for purposes of treatment refers to any animal classified as a mammal, including humans, mice, SCID or nude mice or strains of mice, domestic and farm animals, and zoo, sports, or pet animals, such as sheep, dogs, horses, cats, cows, etc. Preferably, the mammal herein is human.
“Oligonucleotides” are short-length, single- or double-stranded polydeoxynucleotides that are chemically synthesized by known methods (such as phosphotriester, phosphite, or phosphoramidite chemistry, using solid phase techniques such as described in EP 266,032, published 4 May 1988, or via deoxynucleoside H-phosphonate intermediates as described by Froehler et al., Nucl. Acids Res., 14:5399-5407, 1986. They are then purified on polyacrylamide gels.
“Chimeric” antibodies are immunoglobulins in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity (U.S. Pat. No. 4,816,567 and Morrison et al, Proc. Natl. Acad. Sci. USA, 81:6851-6855 (1984)).
“Humanized” forms of non-human (e.g. murine) antibodies are specific chimeric immunoglobulins, immunoglobulin chains or fragments thereof (such as Fv, Fab, Fab′, F(ab) 2 or other antigen-binding subsequences of antibodies) which contain minimal sequence derived from non-human immunoglobulin. For the most part, humanized antibodies are human immunoglobulins (recipient antibody) in which residues from the complementarity determining regions (CDRs) of the recipient antibody are replaced by residues from the CDRs of a non-human species (donor antibody) such as mouse, rat or rabbit having the desired specificity, affinity and capacity. In some instances, Fv framework region (FR) residues of the human immunoglobulin are replaced by corresponding non-human FR residues. Furthermore, the humanized antibody may comprise residues which are found neither in the recipient antibody nor in the imported CDR or FR sequences. These modifications are made to further refine and optimize antibody performance. In general, the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the CDR regions correspond to those of a non-human immunoglobulin and all or substantially all of the FR residues are those of a human immunoglobulin consensus sequence. The humanized antibody optimally also will comprise at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin.
“De-immunized” antibodies are immunoglobulins that are non-immunogenic, or less immunogenic, to a given species. De-immunization can be achieved through structural alterations to the antibody. Any de-immunization technique known to those skilled in the art can be employed. One suitable technique for de-immunizing antibodies is descri bed, for example, in WO 00/34317 published Jun. 15, 2000.
“Homology” is defined as the percentage of residues in the amino acid sequence variant that are identical after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent homology. Methods and computer programs for the alignment are well known in the art.
Throughout the instant specification, hybridoma cell lines, as well as the isolated monoclonal antibodies which are produced therefrom, are alternatively referred to by their internal designation, 7BD-33-11A, 1A245.6, and 11BD-2E11-2 or Depository Designation PTA-4890, PTA-4889 and PTA-5643 respectively
As used herein “ligand” includes a moiety which exhibits binding specificity for a target antigen, and which may be an intact antibody molecule and any molecule having at least an antigen-binding region or portion thereof (i.e., the variable portion of an antibody molecule), e.g., an Fv molecule, Fab molecule, Fab′ molecule, F(ab′).sub.2 molecule, a bispecific antibody, a fusion protein, or any genetically engineered molecule which specifically recognizes and binds the antigen bound by the isolated monoclonal antibody produced by the hybridoma cell line designated as, ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643, (the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antigen).
As used herein “antigen-binding region” means a portion of the molecule which recognizes the target antigen.
As used herein “competitively inhibits” means being able to recognize and bind a determinant site to which the monoclonal antibody produced by the hybridoma cell line designated as ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643, (ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antibody) is directed using conventional reciprocal antibody competition assays. (Belanger L., Sylvestre C. and Dufour D. (1973), Enzyme linked immunoassay for alpha fetoprotein by competitive and sandwich procedures. Clinica Chimica Acta 48, 15).
As used herein “target antigen” is the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643, antigen or portions thereof.
As used herein, an “immunoconjugate” means any molecule or ligand such as an antibody chemically or biologically linked to a cytotoxin, a radioactive agent, enzyme, toxin, an anti-tumor drug or a therapeutic agent. The antibody may be linked to the cytotoxin, radioactive agent, anti-tumor drug or therapeutic agent at any location along the molecule so long as it is able to bind its target. Examples of immunoconjugates include antibody toxin chemical conjugates and antibody-toxin fusion proteins.
As used herein, a “fusion protein” means any chimeric protein wherein an antigen binding region is connected to a biologically active molecule, e.g., toxin, enzyme, or protein drug.
In order that the invention herein described may be more fully understood, the following description is set forth.
The present invention provides ligands (i.e., ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 ligands) which specifically recognize and bind the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antigen.
The ligand of the invention may be in any form as long as it has an antigen-binding region which competitively inhibits the immunospecific binding of the monoclonal antibody produced by hybridoma ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643, to its target antigen. Thus, any recombinant proteins (e.g., fusion proteins wherein the antibody is combined with a second protein such as a lymphokine or a tumor inhibitory growth factor) having the same binding specificity as the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643, antibody fall within the scope of this invention.
In one embodiment of the invention, the ligand is the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antibody.
In other embodiments, the ligand is an antigen binding fragment which may be a Fv molecule (such as a single chain Fv molecule), a Fab molecule, a Fab′ molecule, a F(ab′)2 molecule, a fusion protein, a bispecific antibody, a heteroantibody or any recombinant molecule having the antigen-binding region of the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antibody. The ligand of the invention is directed to the epitope to which the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 monoclonal antibody is directed.
The ligand of the invention may be modified, i.e., by amino acid modifications within the molecule, so as to produce derivative molecules. Chemical modification may also be possible.
Derivative molecules would retain the functional property of the polypeptide, namely, the molecule having such substitutions will still permit the binding of the polypeptide to the ATCC PTA-4890, ATCC PTA-4889, or ATCC PTA-5643 antigen or portions thereof.
These amino acid substitutions include, but are not necessarily limited to, amino acid substitutions known in the art as “conservative”.
For example, it is a well-established principle of protein chemistry that certain amino acid substitutions, entitled “conservative amino acid substitutions,” can frequently be made in a protein without altering either the conformation or the function of the protein.
Such changes include substituting any of isoleucine (I), valine (V), and leucine (L) for any other of these hydrophobic amino acids; aspartic acid (D) for glutamic acid (E) and vice versa; glutamine (Q) for asparagine (N) and vice versa; and serine (S) for threonine (T) and vice versa. Other substitutions can also be considered conservative, depending on the environment of the particular amino acid and its role in the three-dimensional structure of the protein. For example, glycine (G) and alanine (A) can frequently be interchangeable, as can alanine and valine (V). Methionine (M), which is relatively hydrophobic, can frequently be interchanged with leucine and isoleucine, and sometimes with valine. Lysine (K) and arginine (R) are frequently interchangeable in locations in which the significant feature of the amino acid residue is its charge and the differing pK's of these two amino acid residues are not significant. Still other changes can be considered “conservative” in particular environments.
Given an antibody, an individual ordinarily skilled in the art can generate a competitively inhibiting ligand, for example a competing antibody, which is one that recognizes the same epitope (Belanger et al., 1973). One method could entail immunizing with an immunogen that expresses the antigen recognized by the antibody. The sample may include but is not limited to tissue, isolated protein(s) or cell line(s). Resulting hybridomas could be screened using a competing assay, which is one that identifies antibodies that inhibit the binding of the test antibody, such as ELISA, FACS or immunoprecipiation. Another method could make use of phage display libraries and panning for antibodies that recognize said antigen (Rubinstein et al., 2003). In either case, hybridomas would be selected based on their ability to out-compete the binding of the original antibody to its target antigen. Such hybridomas would therefore possess the characteristic of recognizing the same antigen as the original antibody and more specifically would recognize the same epitope.
EXAMPLE 1
Hybridomas Production—Hybridoma Cell Line 7BD-33-11A, 1A245.6, 11BD-2E11-2
Hybridomas:
The hybridoma cell lines 7BD-33-11A and 1A245.6 were deposited, in accordance with the Budapest Treaty, with the American Type Culture Collection, 10801 University Blvd., Manassas, Va. 20110-2209 on Jan. 8, 2003, under Accession Number PTA-4890 and PTA-4889, respectively. In accordance with 37 CFR 1.808, the depositors assure that all restrictions imposed on the availability to the public of the deposited materials will be irrevocably removed upon the granting of a patent.
The hybridoma cell line 11BD-2E11-2 was deposited, in accordance with the Budapest Treaty, with the American Type Culture Collection, 10801 University Blvd., Manassas, Va. 20110-2209 on Nov. 11, 2003, under Accession Number PTA-5643. In accordance with 37 CFR 1.808, the depositors assure that all restrictions imposed on the availability to the public of the deposited materials will be irrevocably removed upon the granting of a patent.
To produce the hybridoma that produce the anti-cancer antibody 7BD-33-11A single cell suspensions of the antigen, i.e. human breast cancer cells, were prepared in cold PBS. Eight to nine weeks old BALB/c mice were immunized by injecting 100 microliters of the antigen-adjuvant containing between 0.2 million and 2.5 million cells in divided doses both subcutaneously and intraperitoneally with Freund's Complete Adjuvant. Freshly prepared antigen-adjuvant was used to boost the immunized mice at between 0.2 million and 2.5 million cells in the same fashion three weeks after the initial immunization, and two weeks after the last boost. A spleen was used for fusion at least two days after the last immunization. The hybridomas were prepared by fusing the isolated splenocytes with Sp2/0 myeloma partners. The supernatants from the fusions were tested for subcloning of the hybridomas.
To produce the hybridoma that produce the anti-cancer antibody 1A245.6 single cell suspensions of the antigen, i.e. human breast cancer cells, were prepared in cold PBS. Eight to nine weeks old BALB/c mice were immunized by injecting 100 microliters of the antigen-adjuvant containing 2.5 million cells in divided doses both subcutaneously and intraperitoneally with Freund's Complete Adjuvant. Freshly prepared antigen-adjuvant was used to boost the immunized mice at 2.5 million cells in the same fashion three weeks after the initial immunization, two weeks later, five weeks later and three weeks after the last boost. A spleen was used for fusion at least three days after the last immunization. The hybridomas were prepared by fusing the isolated splenocytes with NSO-1 myeloma partners. The supernatants from the fusions were tested for subcloning of the hybridomas.
To produce the hybridoma that produce the anti-cancer antibody 11BD-2E11-2 single cell suspensions of the antigen, i.e. human breast cancer cells, were prepared in cold PBS. Eight to nine weeks old BALB/c mice were immunized by injecting 100 microliters of the antigen-adjuvant containing between 0.2 million and 2.5 million cells in divided doses both subcutaneously and intraperitoneally with Freund's Complete Adjuvant. Freshly prepared antigen-adjuvant was used to boost the immunized mice at between 0.2 million and 2.5 million cells in the same fashion two to three weeks after the initial immunization, and two weeks after the last boost. A spleen was used for fusion at least two days after the last immunization. The hybridomas were prepared by fusing the isolated splenocytes with NSO-1 myeloma partners. The supernatants from the fusions were tested for subcloning of the hybridomas.
To determine whether the antibodies secreted by hybridoma cells are of the IgG or IgM isotype, an ELISA assay was employed. 100 microliters/well of goat anti-mouse IgG+IgM (H+L) at a concentration of 2.4 micrograms/mL in coating buffer (0.1M carbonate/bicarbonate buffer, pH 9.2-9.6) at 4° C. was added to the ELISA plates overnight. The plates were washed thrice in washing buffer (PBS+0.05% Tween). 100 microliters/well blocking buffer (5% milk in wash buffer) was added to the plate for 1 hr. at room temperature and then washed thrice in washing buffer. 100 microliters/well of hybridoma supernatant was added and the plate incubated for 1 hr. at room temperature. The plates were washed thrice with washing buffer and 1/5000 dilution of either goat anti-mouse IgG or IgM horseradish peroxidase conjugate (diluted in PBS containing 1% bovine serum albumin), 100 microliters/well, was added. After incubating the plate for 1 hr. at room temperature the plate was washed thrice with washing buffer. 100 microliters/well of TMB solution was incubated for 1-3 minutes at room temperature. The color reaction was terminated by adding 100 microliters/well 2M H 2 SO 4 and the plate was read at 450 nm with a Perkin-Elmer HTS7000 plate reader. As indicated in Table 1 the 7BD-33-11A, 1A245.6, 11BD-2E11-2 hybridomas secreted primarily antibodies of the IgG isotype.
After one to four rounds of limiting dilution hybridoma supernatants were tested for antibodies that bound to target cells in a cell ELISA assay. Three breast cancer cell lines were tested: MDA-MB-231 (also referred to as MB-231), MDA-MB-468 (also referred to as MB-468), and SKBR-3. The plated cells were fixed prior to use. The plates were washed thrice with PBS containing MgCl 2 and CaCl 2 at room temperature. 100 microliters of 2% paraformaldehyde diluted in PBS was added to each well for ten minutes at room temperature and then discarded. The plates were again washed with PBS containing MgCl 2 and CaCl 2 three times at room temperature. Blocking was done with 100 microliters/well of 5% milk in wash buffer (PBS+0.05% Tween) for 1 hr at room temperature. The plates were washed thrice with wash buffer and the hybridoma supernatant was added at 100 microliters/well for 1 hr at room temperature. The plates were washed three times with wash buffer and 100 microliters/well of 1/5000 dilution of goat anti-mouse IgG or IgM antibody conjugated to horseradish peroxidase (diluted in PBS containing 1% bovine serum albumin) was added. After a one hour incubation at room temperature the plates were washed three times with wash buffer and 100 microliter/well of TMB substrate was incubated for 1-3 minutes at room temperature. The reaction was terminated with 100 microliters/well 2M H 2 SO 4 and the plate read at 450 nm with a Perkin-Elmer HTS7000 plate reader. The results as tabulated in Table 1 were expressed as the number of folds above background compared to the IgG isotype control (3BD-27). The antibodies from the 7BD-33-11A and 1A245.6 hybridoma cell lines bound strongly to all 3 breast lines, with binding at least 6 times greater than background. Both antibodies bound most strongly to the MDA-MB-231 cell line. The antibodies from the 11BD-2E11-2 hybridoma cell line also bound most strongly to the MDA-MB-231 cell line, but did not demonstrate binding on the other 2 cell lines greater than background. These results suggest that the epitope recognized by this antibody is not present on MDA-MB-468 or SKBR-3 cells, and is distinct from the epitopes recognized by 7BD-33-11A and 1A245.6.
In conjunction with testing for antibody binding the cytotoxic effect of the hybridoma supernatants were tested in the same breast cancer cell lines: MDA-MB-231, MDA-MB-468 and SKBR-3. The Live/Dead cytotoxicity assay was obtained from Molecular Probes (Eu,OR). The assays were performed according to the manufacturer's instructions with the changes outlined below. Cells were plated before the assay at the predetermined appropriate density. After 2 days, 100 microliters of supernatant from the hybridoma microtitre plates were transferred to the cell plates and incubated in a 5% CO 2 incubator for 5 days. The wells that served as the positive controls were aspirated until empty and 100 microliters of sodium azide and/or cycloheximide was added. 3BD-27 monoclonal antibody was also added as an isotype control since it was known not to bind to the three breast cancer cell lines being tested. An anti-EGFR antibody (C225) was also used in the assay for comparison. After 5 days of treatment, the plate was then emptied by inverting and blotted dry. Room temperature DPBS containing MgCl 2 and CaCl 2 was dispensed into each well from a multichannel squeeze bottle, tapped three times, emptied by inversion and then blotted dry. 50 microliters of the fluorescent Live/Dead dye diluted in DPBS containing MgCl 2 and CaCl 2 was added to each well and incubated at 37° C. in a 5% CO 2 incubator for 30 minutes. The plates were read in a Perkin-Elmer HTS7000 fluorescence plate reader and the data was analyzed in Microsoft Excel. The results were tabulated in Table 1.
Differential cytotoxicity was observed with the 3 antibodies. 11BD-2E11-2 demonstrated killing of 39-73%, with the highest cytotoxicity observed in SKBR-3 cells. 1A245.6 and 7BD-33-11A demonstrated similar cytotoxicity in MDA-MB-231 cells, but 1A245.6 was also cytotoxic to MDA-MB-468 cells, while 7BD-33-11A was not.
This indicated the antibody derived form the hybridoma cell can produce cytotoxicity in cancer cells. There was also a general association between the degree of antibody binding and the cytotoxicity produced by the hybridoma supernatants. There were several exceptions to this trend such as the amount of cytotoxicity produced by 11BD-2E11-2 in MB-468 cancer cells, and SKBR-3 cancers despite a paucity of binding. This suggested that the antibody has a mediating action that was not detected by the cell ELISA binding assay in this cell type, or the assay did not detect the binding, which may be due to the constraints of the assay such as cell fixation. Finally, there existed yet another possibility, that is, the assay was not sensitive enough to detect the binding that was sufficient to mediate cytotoxicity in this particular situation. The other exception was the relative paucity of cytotoxicity of 7BD-33-11A towards MB-468 cells despite a 6 fold increase in binding over the background in comparison to an isotype control. This pointed to the possibility that binding was not necessarily predictive of the outcome of antibody ligation of its cognate antigen. The known non-specific cytotoxic agents cycloheximide produced cytotoxicity as expected.
TABLE 1
Cytotoxicity (%)
Binding (above bkgd)
MB-231
MB-468
SKBR-3
MB-231
MB-468
SKBR-3
Clone
Average
CV
Average
CV
Average
CV
Fold
Fold
Fold
1A245.6
17
7
13
5
44
8
23
10
16
7BD-33-11A
16
2
2
2
29
3
13
6
9
11BD-2E11-2
39
2
66
1
73
18
11
2
1
Cycloheximide
49
9
24
5
56
14
EXAMPLE 2
Antibody Production
Monoclonal antibodies were produced by culturing the hybridomas, 7BD-33-11A, 11A245.6, 11BD-2E 11-2, in CL-1000 flasks (BD Biosciences, Oakville, ON) with collections and reseeding occurring twice/week and standard antibody purification procedures with Protein G Sepharose 4 Fast Flow (Amersham Biosciences, Baie d'Urfé, QC). It is within the scope of this invention to utilize monoclonal antibodies which are humanized, chimerized or murine antibodies. 7BD-33-11A, 1A245.6, 11BD-2E 11-2 were compared to a number of both positive (anti-Fas (EOS9.1, IgM, kappa, 20 micrograms/mL, eBioscience, San Diego, Calif.), anti-Her2/neu (IgG1, kappa, 10 microgram/mL, Inter Medico, Markham, ON), anti-EGFR(C225, IgG1, kappa, 5 microgram/mL, Cedarlane, Romby, ON), Cycloheximide (100 micromolar, Sigma, Oakville, ON), NaN 3 (0.1%, Sigma, Oakville, ON)) and negative (107.3 (anti-TNP, IgG1, kappa, 20 microgram/mL, BD Biosciences, Oakville, ON), G155-178 (anti-TNP, IgG2a, kappa, 20 micro gram/mL, BD Biosciences, Oakville, ON), MPC-11 (antigenic specificity unknown, IgG2b, kappa, 20 microgram/mL), J606 (anti-fructosan, IgG3, kappa, 20 microgram/mL), IgG Buffer (2%)) controls in a cytotoxicity assay (Table 2). Breast cancer (MB-231, MB-468, MCF-7), colon cancer (HT-29, SW1116, SW620), lung cancer (NCI H460), ovarian cancer (OVCAR), prostate cancer (PC-3), and non-cancer (CCD 27sk, Hs888 Lu) cell lines were tested (all from the ATCC, Manassas, Va.). The Live/Dead cytotoxicity assay was obtained from Molecular Probes (Eugene, Oreg.). The assays were performed according to the manufacturer's instructions with the changes outlined below. Cells were plated before the assay at the predetermined appropriate density. After 2 days, 100 microliters of purified antibody was diluted into media, and then were transferred to the cell plates and incubated in a 8% CO 2 incubator for 5 days. The plate was then emptied by inverting and blotted dry. Room temperature DPBS containing MgCl 2 and CaCl 2 was dispensed into each well from a multichannel squeeze bottle, tapped three times, emptied by inversion and then blotted dry. 50 microliters of the fluorescent Live/Dead dye diluted in DPBS containing MgCl 2 and CaCl 2 was added to each well and incubated at 37° C. in a 5% CO 2 incubator for 30 minutes. The plates were read in a Perkin-Elmer HTS7000 fluorescence plate reader and the data was analyzed in Microsoft Excel and the results were tabulated in Table 2. The data represented an average of four experiments tested in triplicate and presented qualitatively in the following fashion: 4/4 experiments greater than threshold cytotoxicity (+++), 3/4 experiments greater than threshold cytotoxicity (++), 2/4 experiments greater than threshold cytotoxicity (+). Unmarked cells in Table 2 represented inconsistent or effects less than the threshold cytotoxicity. The 7BD-33-11A and 1A245.6 antibodies demonstrated cytotoxicity in breast and prostate tumor cell lines selectively, while having no effect on non-transformed normal cells. Both demonstrated a 25-50% greater killing than the positive control anti-Fas antibody. 11BD-2E11-2 was specifically cytotoxic in breast and ovarian cancer cells, and did not affect normal cells. The chemical cytotoxic agents induced their expected cytotoxicity while a number of other antibodies which were included for comparison also performed as expected given the limitations of biological cell assays. In toto, it was shown that the three antibodies have cytotoxic activity against a number of cancer cell types. The antibodies were selective in their activity since not all cancer cell types were susceptible. Furthermore, the antibodies demonstrated functional specificity since they did not produce cytotoxicity against non-cancer cell types, which is an important factor in a therapeutic situation.
TABLE 2
PROS-
BREAST
COLON
LUNG
OVARY
TATE
NORMAL
MB-231
MB-468
MCF-7
HT-29
SW1116
SW620
NCI H460
OVCAR
PC-3
CCD 27sk
Hs888 Lu
11BD2E11-2
−
−
+
−
−
−
−
+
−
−
−
7BD-33-11A
−
−
+
−
−
−
−
−
++
−
−
1A245.6
−
−
+
−
−
−
−
−
++
−
−
Positive Controls
anti-Fas
−
−
+++
−
−
−
−
+++
+
−
+
anti-Her2
+
−
+
−
−
−
−
+
−
−
−
anti-EGFR
−
+++
+
−
+++
−
−
+
−
+
−
CHX
+++
+++
+++
+++
+++
+++
+++
+++
+++
+++
+++
(100 μM)
NaN 3 (0.1%)
+++
+++
+++
+++
−
−
+++
+++
+++
−
−
Negative Controls
IgG1
+++
+
IgG2a
+++
+
IgG2b
+++
IgG3
IgG Buffer
+
Cells were prepared for FACS by initially washing the cell monolayer with DPBS (without Ca ++ and Mg ++ ). Cell dissociation buffer (INVITROGEN) was then used to dislodge the cells from their cell culture plates at 37° C. After centrifugation and collection the cells were resuspended in Dulbecco's phosphate buffered saline containing MgCl 2 , CaCl 2 and 25% fetal bovine serum at 4° C. (wash media) and counted, aliquoted to appropriate cell density, spun down to pellet the cells and resuspended in staining media (DPBS containing MgCl 2 and CaCl 2 ) containing 7BD-33-11A, 1A245.6, 11BD-2E11-2 or control antibodies (isotype control or anti-EGF-R) at 20 micrograms/mL on ice for 30 minutes. Prior to the addition of Alexa Fluor 488-conjugated secondary antibody the cells were washed once with wash media. The Alexa Fluor 488-conjugated antibody in staining media was then added for 20 minutes. The cells were then washed for the final time and resuspended in staining media containing 1 microgram/mL propidium iodide. Flow cytometric acquisition of the cells was assessed by running samples on a FACScan using the CellQuest software (BD Biosciences). The forward (FSC) and side scatter (SSC) of the cells were set by adjusting the voltage and amplitude gains on the FSC and SSC detectors. The detectors for the three fluorescence channels (FL1, FL2, and FL3) were adjusted by running cells stained with purified isotype control antibody followed by Alexa Fluor 488-conjugated secondary antibody such that cells had a uniform peak with a median fluorescent intensity of approximately 1-5 units. Live cells were acquired by gating for FSC and propidium iodide exclusion. For each sample, approximately 10,000 live cells were acquired for analysis and the resulted presented in Table 3. Table 3 tabulated the mean fluorescence intensity fold increase above isotype control and is presented qualitatively as: less than 5 (−); 5 to 50 (+); 50 to 100 (++); above 100 (+++) and in parenthesis, the percentage of cells stained.
TABLE 3
BREAST
COLON
LUNG
OVARY
PROSTATE
Antibody
Isotype
MB-231
MB-468
MCF-7
HT-29
SW1116
SW620
NCI H460
OVCAR
PC-3
11BD2E11-2
IgG1, k
+(61%)
−
−
−
−
−
−
−
−
7BD-33-11A
IgG2a, k
+(96%)
−
+(76%)
+(97%)
+(34%)
+(bimodal, 76%)
+(bimodal, 60%)
+(51%)
+(75%)
1A245.6
IgG1, k
+(98%)
+(78%)
+(74%)
++
+(23%)
+(bimodal, 71%)
+(bimodal, 70%)
+(73%)
+(bimodal, 72%)
anti-EGFR
IgG1, k
++
++bimodal
−
+(97%)
+(43%)
−
+(bimodal, 80%)
+(90%)
+(96%)
anti-FAS
IgM, k
−
−
−
+(30%)
−
−
+(61%)
−
−
Representative histograms of 7BD-33-11A antibodies were compiled for FIG. 1 , 1A245.6 antibodies were compiled for FIG. 2 , 11BD-2E11-2 were compiled for FIG. 3 and evidence the binding characteristics, inclusive of illustrated bimodal peaks, in some cases. 11BD-2E11-2 displayed specific tumor binding to the breast tumor cell line MDA-MB-231. Both 7BD-33-11A and 11A245.6 displayed similar binding to cancer lines of breast (MDA-MB-231 and MCF-7), colon, lung, ovary, and prostate origin and differential binding to one of the breast cancer cell lines (MDA-MB-468). There was binding of all three antibodies to non-cancer cells, however that binding did not produce cytotoxicity. This was further evidence that binding was not necessarily predictive of the outcome of antibody ligation of its cognate antigen, and was a non-obvious finding. This suggested that the context of antibody ligation in different cells was determinative of cytoxicity rather than just antibody binding.
EXAMPLE 3
In Vivo Experiments:
Now with reference to the data shown in FIGS. 5 and 6 , four to eight week old, female SCID mice were implanted with 5 million MDA-MB-231 human breast cancer cells in one hundred microliters injected subcutaneously in the scruff of the neck. The mice were randomly divided into four treatment groups of ten. On the day prior to implantation 20 mg/kg of either 11BD2E-11-2, 7BD-33-11A, 1A245.6 test antibodies or 3BD-27 isotype control antibody (known not to bind MDA-MB-231 cells) were administered intrapertioneally at a volume of 300 microliters after dilution from the stock concentration with a diluent that contained 2.7 mM KCl, 1 mM KH 2 PO 4 , 137 mM NaCl, 20 mM Na 2 HPO 4 . The antibodies were then administered once per week for a period of 7 weeks in the same fashion.
Tumor growth was measured about every seventh day with calipers for up to ten weeks or until individual animals reached the Canadian Council for Animal Care (CCAC) end-points. Body weights of the animals were recorded for the duration of the study. At the end of the study all animals were euthanised according to CCAC guidelines. There were no clinical signs of toxicity throughout the study. Body weight measured at weekly intervals was a surrogate for well-being and failure to thrive. There was a minimal difference in weight for the groups treated with the isotype control, 3BD-27, and 7BD-33-11A, 1A245.6, or 11BD-2E11-2. At day 60 (11 days after the cessation of treatment) tumor volume of the group treated with 1A245.6 was 5.2% of the control group (p=0.0002) and demonstrated effectiveness at reducing tumor burden with antibody treatment. Those mice bearing cancer treated with 7BD-33-11A antibody were disease free and had no tumor burden. The tumor volume was lower in the 11BD-2E 11-2 treatment group (45% of control) at day 67 (p=0.08). This also demonstrated a lesser tumor burden with cytotoxic antibody treatment in comparison to a control antibody. There was also corresponding survival benefits ( FIG. 6 ) from treatment with 7BD-33-11A, 1A245.6, and 11BD-2E11-2 cytotoxic antibodies. The control group treated with 3BD-27 antibody reached 100% mortality by day 74 post-implantation. In contrast, groups treated with 7BD-33-11A were disease free and 1A245.6 treated animal displayed 100% survival and the group treated with 11BD-2E11-2 had 24% survival.
In toto, cytotoxic antibody treatment produced a decreased tumor burden and increased survival in comparison to a control antibody in a well recognized model of human cancer disease suggesting pharmacologic and pharmaceutical benefits of these antibodies (7BD-33-11A, 1A245.6, 11BD-2E11-2) for therapy in other mammals, including man.
EXAMPLE 4
In Vivo Established Tumor Experiments:
Five to six week old, female SCID mice were implanted with 5 million MDA-MB-231 breast cancer cells in one hundred microliters injected subcutaneously in the L scruff of the neck. Tumor growth was measured with calipers every week. When the majority of the cohort reached a tumor volume of 100 mm 3 (range 50-200 mm 3 ) at 34 days post implantation 8-10 mice were randomly assigned into each of three treatment groups. 7BD-33-11A, 1A245.6 test antibodies or 3BD-27 isotype control antibody (known not to bind MDA-MB-231 cells) were administered intrapertioneally with 15 mg/kg of antibodies at a volume of 150 microliters after dilution from the stock concentration with a diluent that contained 2.7 mM KCl, 1 mM KH 2 PO 4 , 137 mM NaCl, 20 mM Na 2 HPO 4 . The antibodies were then administered three times per week for 10 doses in total in the same fashion until day 56 post-implantation. Tumor growth was measured about every seventh day with calipers until day 59 post-implantation or until individual animals reached the Canadian Council for Animal Care (CCAC) end-points. Body weights of the animals were recorded for the duration of the study. At the end of the study all animals were euthanised according to CCAC guidelines.
There were no clinical signs of toxicity throughout the study. Body weight was measured at weekly intervals. There was no significant difference in weight for the groups treated with the isotype control and 7BD-33-11A, or 1A245.6 antibodies. As can be seen in FIG. 4 , at day 59 post-implantation (2 days after the cessation of treatment), tumor volume of the group treated with 7BD-33-11A was 29.5% of the control group (p=0.0003). In this group, there was also a trend toward regression in mean tumor volume when the value for day 59 was compared to day 52 (p=0.25). Likewise, treatment with 1A245.6 antibody also significantly suppressed tumor growth and decreased tumor burdens. Animals with established tumors treated with this antibody had tumor volumes that were 56.3% of the isotype treated control group (p=0.017).
In toto, treatment with 7BD-33-11A or 1A245.6 antibodies significantly decreased the tumor burden of established tumors in comparison to a control antibody in a well recognized model of human cancer disease suggesting pharmacologic and pharmaceutical benefits of these antibodies for therapy in other mammals, including man.
All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement of parts herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification. One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those inherent therein. Any oligonucleotides, peptides, polypeptides, biologically related compounds, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The present invention relates to a method for producing patient cancerous disease modifying antibodies using a novel paradigm of screening. By segregating the anti-cancer antibodies using cancer cell cytotoxicity as an end point, the process makes possible the production of anti-cancer antibodies for therapeutic and diagnostic purposes. The antibodies can be used in aid of staging and diagnosis of a cancer, and can be used to treat primary tumors and tumor metastases. The anti-cancer antibodies can be conjugated to toxins, enzymes, radioactive compounds, and hematogenous cells. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a device for detecting a particular point of a human body, and more particularly for detecting the impedance of the skin as a change of electric current.
In general, such a device for detecting a particular point of a human body uses a special cell or battery as its electric source in consideration of safety to the human body. (The particular point is a general term expressing portions that exist in several hundred portions of a human body and that correspond to important points of a particular circulating and reacting system which is different from the lymph system and nerve system in the human body and which comprises a main range including a part of an artery and a branch range including a part of a vein, the particular point being called a "tsubo spot" in Chinese medicine). However, in such a known device, a detecting portion of the device is continuously in contact with a particular point (tsubo spot of skin) of a human body, that is, a point of low impedance. Therefore, the cell is quickly consumed by the continuously generated detecting signals and therefore it is very uneconomical. In such a known device for detecting a particular body point, there is further used means for searching for a particular body point which is called a searching bar. This known searching bar is straight in shape and a probe is mounted on its leading end. There is also known an instrument for diagnosing ears which is classified as a device for detecting a particular body point and which is adapted electrically to search for a particular point existing in ears of a human body. The above known searching bar is also used in the instrument for diagnosing ears in the above shape. However, since the ear has a considerably complicated structure with undulations and the visual field of the inspector is intercepted by his hand supporting the searching bar of linear shape, it is very difficult for the inspector to visually confirm a particular point searched out by the searching bar. Accordingly, it not only becomes a factor of misreading by misleading a position of such a particular body point, but the medical treatment is interfered with. In general, since the searching bar is connected with a body of the device through the intermediary of a cord and the indicating part for indicating a reaction of the particular body point is provided at the body side, it is a defect that on searching, the inspector must watch both the searching portion and the indicating part of the body at the same time.
As mentioned above, the known instrument for diagnosing ears has a searching bar with a probe. The searching bar is grasped by the inspector and the probe provided on the bar is applied to the ear of the person to be inspected whereby the instrument is constituted to search for a particular point by passing a small electrical current in the auricular conch from the searching bar. However, the skin resistance of the person to be inspected has a personal difference depending upon age, condition or the like and therefore the reaction of a particular point may be changed on each search which is carried out by a searching bar which is adjusted to a fixed sensitivity. In general, the inspector carrying out such a diagnosis finds out four or five particular points and judges fairly these particular points according to the theory of entrails. However, if the sensitivity of the searching bar or the instrument for diagnosing ears is fixed as mentioned before, the reaction varies according to each person to be inspected notwithstanding that it is under the fixed condition, or varies according to each day to be inspected in spite of the same person being inspected, and therefore these inconveniences become a factor of misdiagnosis.
It is an object of the present invention to provide a device for detecting a particular point of a human body which does not have the defects mentioned above.
It is another object of the invention to provide a device for detecting a particular point of a human body having a time limit circuit in order to eliminate unnecessary exhaustion of its energy cell.
It is a further object of the invention to provide a device for detecting a particular point of a human body, in particular, an instrument for diagnosing ears, including a searching bar which is easy to use and observe and which has a small incidence of misdiagnosis.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, there is provided a device for detecting a particular point of a human body which comprises means for detecting an impedance value of skin resistance as a function of electric current, and a time limit circuit which is actuated only one time according to the detecting signal.
According to another aspect of the invention, there is provided a searching bar used in an instrument for diagnosing ears, comprising a bent or curved end portion on which a probe is mounted, and a luminous element disposed near the bent or curved end to form an easily observed indicating portion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view showing one embodiment of a searching bar according to the invention;
FIG. 2 is a pictorial view showing another embodiment of a searching bar according to the invention;
FIG. 3 is a pictorial view showing a further embodiment of a searching bar according to the invention;
FIG. 4 is a circuit diagram showing a time limit circuit according to the invention; and
FIGS. 5A -5C are graphical representations showing the relationship between voltage and time at points "a", "b" and "c", respectively, in the circuit of FIG. 4.
DETAILED DESCRIPTION
Referring now to FIG. 1, a searching bar 1 has a probe 2 mounted at the leading end thereof. The searching bar 1 of bar-like body shape has a grip portion 1a and a leading portion 1b angularly disposed relative to grip portion 1a. The leading portion 1b is formed to be capable of easily performing a visual confirmation of a particular body point when an inspector searches, for example, a particular point in an auricular conch by grasping the searching bar 1. Accordingly, for this purpose it is essential that the inspector's hand grasping the searching bar 1 does not obstruct his visual confirmation of the particular body point. In the embodiment shown in FIG. 1, an angle of about 45° is set as a bending angle between the longitudinal axis 1 1 of the grip portion 1a and the longitudinal axis 1 2 of the leading portion 1b. Near the leading portion 1b is disposed a luminous element 3, for example a luminous diode which lights up according to the current passing through, caused by the reaction at the particular body point to provide a visual indication portion 4. In this embodiment the indicating portion 4 is substantially placed on the longitudinal axis 1 2 of the leading portion 1b, that is, on the extension line of the probe 2 so that it is easily viewed. The searching bar 1 is connected to the body (not shown) by means of a cord 5. Since the above searching bar 1 is bent at its leading end the visual field of the inspector is not interrupted by his hand grasping the searching bar and the detection of the particular body point may be easily carried out even at a position hard to search, for example, a fold portion on the auricular conch, a complicated body portion or the like. Arrival at the particular body point may be confirmed immediately by luminescence of the indicating portion 4.
Referring to FIG. 2, there is shown a searching bar which is a combination type, particularly suitable for instruments for diagnosing ears. The searching bar comprises a cylindrical base 21 and one of adapters 24, 24', and 24". The base 21 contains a connector 22 connected to a cord 23 therein. The adapters 24, 24', and 24" are formed in a bend and probes 25, 25' and 25" are mounted on the respective leading portions of the adapters. In the adapters 24, 24', and 24" are contained respective electrical resistors 26, 26', and 26" of which each resistance value differs from the other in steps. Terminals 27, 27', and 27" are provided at the respective rear ends of the adapters. On each shoulder or bend portion of the adapters are disposed luminous elements 28, 28', and 28", respectively, which are incorporated in the circuit of each adapter. The terminals 27, 27', and 27" are constructed to fit in connector 22 to electrically connect the adapters to cord 23 when the adapter is fixed to the base 21.
As mentioned above, the searching bar for the instrument for diagnosing ears in the FIG. 2 embodiment is formed by fixing selectively one of the adapters 24, 24', and 24" to the base 21. Therefore, the inspector can vary the sensitivity of the searching bar according to the person to be inspected, upon searching the particular point of the latter.
Referring to FIG. 3, there is shown a searching bar in which connectors 42, 42' and 42" are mounted in respective adapters 44, 44', and 44" and a terminal 47 is provided on a base 41. In this embodiment, the other constructional features are similar to those of the embodiment shown in FIG. 2. In FIGS. 2 and 3, though the searching bar is shown for use with three adapters, it will be understood that the searching bar can be provided with more than three adaptors. Further, it is preferable that a suitable marking or indication is added to the adapters to distinguish them from each other.
Referring to FIG. 4, there is shown a time limit circuit adapted to avoid unnecessary exhaustion of the cell or battery B which is used as a power source of the device for detecting a particular body point according to the invention. To a plus side of the power source battery B is connected a portion for detecting a particular body point comprised of searching bar through the intermediary of a resistor R 1 and terminal "a". To a minus side of battery B is connected an abutting portion suitable for abutting to a human body. To the second side of the resistor R 1 is connected through a capacitor C 1 the base of a transistor Q 1 . The emitter of transistor Q 1 is connected between the resistor R 1 and the power source B and the collector is connected to the minus terminal of the power source B through a resistor R 2 . A time limit circuit is constructed by connecting capacitor C 2 between the first side of the resistor R 2 and the plus terminal of the power source B. A speaker 31 is connected to the output side of the capacitor C 2 through the intermediary of an amplifier 30. Further, an ammeter 32 and/or a luminous diode 33 may be connected to the output of amplifier 30.
In the circuit of FIG. 4, the voltage E of the power source B is introduced to the point "a" connected to the portion for detecting a particular body point through the resistor R 1 . If t 1 expresses a time which permits the portion for detecting a particular body point to abut to the human body having an impedance R x , the voltage Va at the point "a" is expressed by the following equation (see FIG. 5).
va=E·(R.sub.x /R.sub.1 +R.sub.x)
Although the voltage Vb at the point "b" is usually equal to the voltage E, it drops down to the voltage of the point "a" at the beginning of the time t 1 when the portion for detecting a particular body point is applied to a certain position of the human body at which the impedance becomes Rx, and returns to the initial voltage of Vb=E according to variation of time constant t 2 =0.7.C 1 ·Rx which is decided by the resistance value Rx and the capacitance of the capacitor C 1 . See FIG. 5B.
The current flows to the base of the transistor Q 1 according to the variation of the voltage Vb of the above mentioned point "b", and therefore in proportion to the degree of amplification of the transistor Q 1 , the current flows from the emitter to the collector.
Accordingly, when the transistor Q 1 is turned on the voltage Vc at the point "c" rises up to the voltage E and the voltage Vc lowers down to 0 volts according to a time constant t 3 =0.7·C 2 ·R 2 which is decided by the resistor R 2 and the capacitor C 2 . Consequently, the time constant t 3 showing a fall time of the output voltage from the point "c" is decided by the resistor R 2 and the capacitor C 2 in spite of the length of the time constant t 1 . Thus, a time limit circuit is constituted.
Further, though the time when the transistor Q 1 is turning on is decided by the capacitance of the capacitor C 1 the maximum value of the time is limited by the impedance R x of the human body (usually about 20 kΩ-50 kΩ).
Even if the detecting portion is continued to be applied to the human body, that is, even if the time t 1 is lengthened, since the transistor Q 1 becomes "ON" only for one time at the initial stage of the time t 1 , the current thereafter does not flow in the testing circuit under the action of the time limit circuit.
The amplifier 30 is actuated by the output from point "c" to generate the detecting sound from the speaker 31. At the same time, indication is carried out by the meter 32 and/or the lighting of a luminous diode 33 whereby the user is informed that the position of the particular point, for example, a tsubo spot of the human body, has been detected. Further, in order to heighten safety to the human body, the power voltage shall be DC 12-18V, and the value of the resistor R 1 shall be more than 200 kΩ.
Accordingly, since the current passing to the human body through the resistor R 1 and the detecting portion is less than 60 μA, even if Rx=0 it does not have a great influence upon the exhaustion of the cell or battery B. Because the current consumed is 1 mA in the case of a meter and 5 mA-30 mA in the case of luminous diode, even if this current is used only for the time fixed by the t 3 , the time cell is very slight depleted in respect to its exhaustion and it is economically utilized.
It is further understood by those skilled in the art that the foregoing description is a preferred embodiment of the disclosed device and that various changes and modifications may be made in the invention without departing from the spirit and scope thereof. | A device for detecting the impedance of the skin of a human body as a change of electric current comprises a time limit circuit which permits actuation of the device only one time according to a signal detected. A searching bar is coupled to the time limit circuit and has a curved or bent portion near which a luminous element is disposed. This searching bar may have adjustable sensitivity. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Priority of U.S. Provisional Patent Application Ser. No. 60/989,162, filed Nov. 20, 2007, incorporated herein by reference, is hereby claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to portable and/or quickly constructed levees. More particularly, the present invention relates to a levee apparatus that employs base panels and inclined panels that interlock to provide a generally triangular cross section with an interior that can be filled with a selected fill material (e.g. soil, sand, gravel, etc.), wherein alternating projections and sockets/apertures along edges of the panels interlock to form a connection of each panel to other of the panels.
2. General Background of the Invention
Levees are often constructed of earthen material. In some locations the side of an earthen levee is lined with concrete. The U.S. Army Corps of Engineers has for years constructed earthen levees with a portion of a side of the levee being covered with a layer of reinforced concrete. At the U.S. Army Corps of Engineers facility at Vicksburg, Miss., concrete levee mats have been fabricated for years.
Portable levee systems have been patented as noted in the following table of possibly related art.
The following U.S. Patents are incorporated herein by reference:
TABLE
Pat. No.
TITLE
ISSUE DATE
274,449
Building Brick
Mar. 20, 1883
277,732
Method of Constructing Levees and
May 15, 1883
Embankments
390,175
Hollow Building Block or Brick
Sep. 25, 1888
945,859
Building Block
Jan. 11, 1910
1,002,161
Sea Wall Construction
Aug. 29, 1911
1,552,077
Block for Building Construction
Sep. 01, 1925
2,466,343
Jetty
Apr. 05, 1949
3,441,140
Drain Filter
Apr. 29, 1969
3,645,100
Leaching Chamber Unit for Soil
Feb. 29, 1972
Absorption System
4,073,245
Levee Forming Apparatus and Method
Feb. 14, 1978
4,175,888
Block for Constructing Breakwater
Nov. 27, 1979
4,189,252
Undersea Platform Construction System
Feb. 19, 1980
4,192,628
Flow Distributor for Leaching Fields
Mar. 11, 1980
4,341,050
Construction Module
Jul. 27, 1982
4,345,856
Composition and Process for Stabilizing
Aug. 24, 1982
Embankments
4,431,337
Wave Dissipation Caisson
Feb. 14, 1984
4,465,399
Artificial Reef Assembly Construction
Aug. 14, 1984
and a Method
4,661,014
Prefabricated Civil Engineering
Apr. 28, 1987
Module, Method for the Construction
of a Structure Including Said Module
and Resulting Structure
4,869,620
Method and Apparatus for Constructing
Sep. 26, 1989
Seawalls and Docks
4,903,782
Levee Squeezer
Feb. 27, 1990
4,954,013
Means and Method for Stabilizing
Sep. 04, 1990
Shorelines
5,017,042
Fluid Directing Systems
May 21, 1991
5,118,222
Method and Apparatus for Constructing
Jun. 02, 1992
Seawalls and Docks
5,403,125
Method and Apparatus for Providing
Apr. 04, 1995
Underground Barrier
5,599,136
Structure for Topography Stabilization
Feb. 04, 1997
and Runoff Control
5,971,661
Water Containment Device and Levee
Oct. 26, 1999
for Impeding a Flow of Water
6,012,872
Flood Control System
Jan. 11, 2000
6,390,154
Portable Levee System and Portable
May 21, 2002
Levee System Bag
6,443,652
Aggregate Chamber Leach Lines for
Sep. 03, 2002
Leaching Effluent and Associated
Method
6,485,230
Submersible Modular Dike and Method
Nov. 26, 2002
for Segregating Body of Water
2002/0197112
Structure and Method for Detecting
Dec. 26, 2002
an Inflated State of a Flexible Mem-
brane Dam
6,558,075
Permanent and Semi-Permanent Groyne
May 06, 2003
Structures and Method for Shoreline
and Land Mass Reclamation
2003/0118407
Transportable Dam and a Method of
Jun. 26, 2003
Erecting the Same
2003/0156903
Frame Members for a Portable Dam
Aug. 21, 2003
6,637,474
Portable Levee System
Oct. 28, 2003
2004/0047688
Liquid Containment/Diversion Dike
Mar. 11, 2004
2004/0131430
Retaining Wall Block and Drainage
Jul. 08, 2004
System
2004/0156680
Beach Stabilizing Blocks
Aug. 12, 2004
2004/0234340
Mobile Levee System
Nov. 25, 2004
2004/0261890
Portable Levee System
Dec. 30, 2004
2005/0053429
Modular Retaining Wall
Mar. 10, 2005
2005/0158122
Method for Constructing Check Dam
Jul. 21, 2005
or Fire Prevention Dam Using Gear-
Type Block
2005/0260038
Hydraulic Dam
Nov. 24, 2005
2006/0000179
Building Block
Jan. 05, 2006
2006/0275081
Modular Dike for Shore Protection
Dec. 07, 2006
7,214,005
Sectionalized Flood Control Barrier
May 08, 2007
2007/0116522
Flood Levee and Barrier Module and
May 24, 2007
System
2007/0154264
Portable Dike and Floatation Device
Jul. 05, 2007
2007/0196178
Portable Levee System
Aug. 23, 2007
JP56-77413
Dam
Jun. 25, 1981
JP2112512
Wave Dissipation Submerged Dike
Apr. 25, 1990
JP6041934
Submerged Breakwater
Feb. 15, 1994
ES2097789
Breakwater
Apr. 16, 1997
WO99/03659
Concrete Block, Joint for the Same,
Jan. 28, 1999
and Structure of Concrete Blocks
WO99/11868
Dike Module
Mar. 11, 1999
WO99/57376
A Technique and a Device for Building
Nov. 11, 1999
Protective Sea Walls or Artificial
Reefs Made of Modular Parts
EP1,193,348
Modular Elements to be Cast and
Apr. 03, 2002
Fixed in Seabeds or the Like for the
Re-formation of Aquatic Life
WO02/068770
Fluent Material Confinement System
Sep. 06, 2002
EP1,418,376
Method and Structure for Connecting
May 12, 2004
Difficult&minus; TO&minus; Join
Pipes to be Used at High
Temperature
EP1,508,643
Flood Barrier
Feb. 23, 2005
BRIEF SUMMARY OF THE INVENTION
The present invention provides an improved levee apparatus that employs multiple interlocking panels to form an elongated hollow structure with an interior that accepts a selected fill material such as sand, gravel, soil or the like.
In various embodiments reinforcement is provided in the interlocking panels, such as re-bar and/or wire mesh. In one embodiment reinforcement can be used to lock one or more of the interlocking panels.
In one embodiment one or more of the panels can comprise concrete.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
FIG. 1 is a plan view of one of the side panel portions of the preferred embodiment of the apparatus of the present invention;
FIG. 2 is an end view taken along lines 2 - 2 of FIG. 1 ;
FIG. 3 is a plan view of one of the base panel portions of the preferred embodiment of the apparatus of the present invention;
FIG. 4 is an end view taken along lines 4 - 4 of FIG. 3 ;
FIG. 5 is a plan view of the preferred embodiment of the apparatus of the present invention;
FIG. 6 is a plan view of the preferred embodiment of the apparatus of the present invention illustrating installation of one of the inclined side panels upon the base panels;
FIG. 7 is a sectional view taken along lines 7 - 7 of FIG. 6 ;
FIG. 8 is a perspective view of the preferred embodiment of the apparatus of the present invention;
FIG. 9 is a partial perspective view of a second embodiment of the apparatus of the present invention;
FIG. 10 is a sectional view of the second embodiment of the apparatus of the present invention;
FIG. 11 is a sectional view of the second embodiment of the apparatus of the present invention;
FIG. 12 is a side view of the preferred embodiment of the apparatus of the present invention, showing use of the side panels without the base panels;
FIG. 13 is a perspective fragmentary view of the preferred embodiment of the apparatus of the present invention;
FIG. 14 is a perspective view of an additional embodiment of the apparatus of the present invention; and
FIG. 15 is a sectional view taken along lines 15 - 15 of FIG. 14 .
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-8 and 13 show the preferred embodiment of the apparatus of the present invention, designated generally by the numeral 10 in FIGS. 6-8 . Levee apparatus 10 provides a base panel 12 that interlocks with a pair of inclined side panels 29 . Base panels 12 are place end-to-end. Side panels 29 are then connected to the base panels 12 . Side panels 29 are connected to each other at apex 66 . The panel 12 and the inclined side panels 29 are connected in a staggered, brick lay type pattern as shown in FIGS. 5-8 and 13 . Once connected together, the panels 12 , 13 form a generally triangular cross section (see FIG. 7 ).
In FIGS. 1-2 , a side panel 29 is shown in more detail. Side panel 29 has end edges 30 , 31 , upper surface 44 , lower surface 45 , upper edge 49 and lower edge 50 . Side panel 29 has projections 32 that are spaced apart along upper edge 49 . A gap 33 is placed between each pair of projections 32 .
At end edge 31 , there is a notch 34 near upper edge 49 and a notch 35 next to lower edge 50 . Similarly, there are projections 36 and gaps 37 along lower edge 50 . A beveled or inclined surface 40 is provided next to each gap 37 . These surfaces 40 are bearing surfaces that bear against contact area 43 on the upper surface 20 of base panel 12 . Surfaces 40 , 41 , 42 surround each gap 37 . Each gap 33 can be generally rectangular in shape, surrounded by three surfaces that are normal to both the upper 44 and the lower 45 surfaces of side panel 29 . Projections 38 , 39 are next to end edge 30 . Each projection 38 , 39 can share an edge with end edge 30 as shown in FIG. 1 .
Base panel 12 is shown in more detail in FIGS. 3 and 4 . Base panel 12 has end edges 13 , 14 and side edges 15 , 16 . A plurality of apertures 17 are provided along each edge 15 , 16 as shown in FIGS. 3-4 . Each aperture 17 extends through panel 12 , communicating with upper surface 20 and lower surface 21 as shown in FIGS. 3-4 .
Notches 18 , 19 are provided on panel 12 . Notch 18 is positioned next to the side edge 15 and communicating with the end edge 13 . Notch 19 is positioned next to the side edge 16 and communicating with the end edge 14 .
Each aperture 17 is bordered by a beveled or inclined surface 22 that forms an acute angle with panel 12 lower surface 21 as shown in FIGS. 3-4 . Each aperture 17 is also surrounded by or bordered by surfaces 23 , 24 , 25 that are surfaces preferably normal to surfaces 20 , 21 . Each notch 18 , 19 is surrounded by or bordered by surfaces 26 (beveled or inclined), 27 , 28 . A contact or load transfer area 43 on base panel 12 is engaged and contacted by a diagonally extending or beveled surface 40 of a side panel 29 as shown in FIGS. 1-5 and 13 . Each base panel 12 and side panel 29 can be reinforced with reinforcing steel 71 or any other suitable reinforcement.
To erect levee apparatus 10 , base panels 12 are placed end-to-end as shown in FIGS. 5 and 6 . The end edge 13 of one base panel 12 is place next to and aligned with the end edge 14 of another base panel 12 . Side panels 29 can be attached to base panels 12 in an alternating, brick layered type pattern of FIGS. 5-6 and 13 (see arrows 46 , 67 ). Each side panel 29 thus preferably attaches to a pair of base panels 12 as well as to a pair of side panels 29 at apex 66 (see FIG. 7 ).
Bolted connections 52 can be used to affix each pair of side panels to support 47 as shown in FIG. 7 . Each bolted connection 52 can employ a bolt or fastener 53 that engages an internally threaded opening 54 in support panel 47 . An opening 55 is a bolt opening that enables each fastener to pass through a panel 29 .
An air space 56 is provided below the erected side panels 29 as shown in FIG. 7 . Fill opening 57 enables a selected fill material 59 (e.g. sand, soil, gravel) that is suitable for the construction of levees to be added to space 56 . Cap or cover 58 seals or covers fill opening 57 before and after filling space 56 with fill material 59 .
FIGS. 9-11 show an alternate levee apparatus 11 that uses a plurality of inclined panels 63 secured to a water bed 61 that is under a water body 60 . Piling 62 , triangular panels 63 and fill material 65 hold panels 63 in an inclined position. In various embodiments the angle of inclination can be about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 89, and 90 degrees with the water bed 61 . In various embodiments the angle of inclination can be in a range of between about any two of the above referenced angles.
Once piling 62 , panels 63 , 64 and fill material 65 have been erected, levee apparatus 10 ( FIGS. 1-8 and 12 - 13 ) can be erected upon fill material 65 as shown in FIG. 11 .
Arrows 68 in FIG. 11 show water flow over levee 11 during a storm surge. Water flows over levee 11 carrying accretions 69 that accumulate to form a new land mass that supports plant life 70 for replenishment of wetlands that have eroded.
FIG. 12 illustrates that side panels 29 can be erected and interlocked at apex 77 and held in position using piling 62 rather than base panel 12 . In FIG. 12 , the side panels 29 would be interlocked and brick layed staggered fashion as with the embodiment of FIGS. 1-11 . However, pilings 62 support two panels 29 in an inclined position forming a generally triangularly shaped levee which can be back filled with a selected fill material such as sand, gravel, soil, or the like. In FIG. 12 , notice that the side panels 29 can be of differing sizes to accommodate changes in elevation of water bottom 61 .
FIGS. 14 and 15 show an additional alternate embodiment of the apparatus of the present invention designated generally by the numeral 72 . Levee apparatus 72 is comprised of a plurality of sections 73 , 74 , 75 and possibly additional sections that are connected end to end as shown in FIG. 14 . Each section provides a first end portion 76 that interlocks with a second end portion 77 . The end portion 76 provides a socket 78 that is receptive of an end portion 77 of another section as shown in FIG. 15 . A stop 79 limits the amount of penetration of end portion 76 into socket 78 as shown in FIG. 15 .
Each section 73 , 74 , 75 can provide an opening 80 that can be closed using a cap 81 . Opening 80 and cap 81 enable fill material such as sand, gravel, soil, or other suitable fill material to be added to the interior 82 of each section 73 , 74 , 75 . The levee apparatus 72 shown in FIGS. 14 and 15 could be employed in situations such as those shown and described with respect to FIGS. 1-13 .
As an alternative to the sections 73 , 74 , 75 shown in FIGS. 14 and 15 , similarly connecting interlocking sections could be provided wherein each section has a gradual taper along its length. An end portion of each section is of a slightly larger, generally triangular cross section. The other end portion of that section is of a smaller, generally triangular cross section. In such a case, an end portion of one such tapered section fits into the end portion of another such tapered section. In this embodiment a section can be pulled longitudinally from a mold for forming the panel. Alternatively, the mold can be made in interlocking sections which lock when section is poured and cured, and unlock after section has cured.
In one alternative embodiment can be included a variation of the embodiment shown in FIGS. 9 through 11 . In this embodiment the upper portion of the levee barrier (panels 29 ) does not span from edge to edge of the lower portion of the barrier (panels 63 )—as shown in FIGS. 10 and 11 . Instead, a smaller portion (with spaced apart edges) compared to the larger lower portion is used. In various embodiments the upper portion can span about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, and 95 percent of the width of the upper part of the lower portion. In various embodiments the spanning percentage can be in a range of between about any two of the above referenced percentages.
The following is a list of parts and materials suitable for use in the present invention.
PARTS LIST
Part Number
Description
10
levee apparatus
11
levee apparatus
12
base panel
13
end edge
14
end edge
15
side edge
16
side edge
17
aperture
18
notch
19
notch
20
upper surface
21
lower surface
22
diagonally extending surface
23
surface
24
surface
25
surface
26
diagonally extending surface
27
surface
28
surface
29
inclined side panel
30
end edge
31
end edge
32
projection
33
gap
34
notch
35
notch
36
projection
37
gap
38
projection
39
projection
40
diagonally extending surface
41
surface
42
surface
43
contact area
44
upper surface
45
lower surface
46
arrow
47
support
48
lower surface
49
arrow
50
upper edge
51
lower edge
52
bolted connection
53
fastener
54
internally threaded opening
55
bolt opening
56
air space
57
fill opening
58
cap
59
fill material
60
water body
61
waterbed
62
piling
63
inclined panel
64
triangular panel
65
fill
66
apex
67
arrow
68
arrow
69
accretions
70
plant life
71
reinforcing steel
72
levee apparatus
73
section
74
section
75
section
76
first end portion
77
second end portion
78
socket
79
stop
80
opening
81
cap
82
interior
All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.
The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. | A levee apparatus is constructed of base panels connected end to end and supported by an underlying support such as the earth's surface. Side panels interlock with the base panels and with each other to form a generally triangular transverse cross section and a hollow interior that can be filled with a selected fill material. Interlocking projections on the side panels interlock with apertures of the base and with notches or recesses of other side panels. | 4 |
This is a continuation of application Serial No. 711,883 filed Mar. 15, 1985, which is a divisional of Serial No. 441,023, filed Nov. 12, 1982, both are now abandoned.
BACKGROUND OF THE INVENTION
With the introduction of glutaraldehyde preservation of biological tissue, and in particular porcine bioprosthetic heart valves, it has become possible to: (a) overcome the poor performance of early formaldehyde-preserved implanted tissue valves; (b) discontinue the use of homograft valves; and (c) avoid the undesirable use of anitcoagulants required to prevent thromboembolism associated with the use of non-bioprosthetic (mechanical) heart valves, especially in children. Not unlike other similarly important discoveries, however it appears that the glutaraldehyde-preserved bioprosthesis has created its own dilemma.
Although the relatively biologically inert glutaraldehyde-preserved valves of Carpentier and others have demonstrated excellent long-term durability in most instances, serious drawbacks such as tissue-fatigue and a propensity toward calcification have occured. Moreover, it was initially contemplated that children and adolescents would be among those deriving the greatest benefit from the glutaraldehyde-preserved bioprosthetic heart valves since the anticoagulants required with mechanical prostheses could be eliminated. Results from an increasing number of recent clincial studies indicate that severe calcification of these tissues with relatively short-term failure is prevalent among children and adolescents. Thus, despite their long-term durability and overall reduced incidence of complications, these glutaraldehyde-preserved valves have been deemed by some to be unsuitable for use in children.
Calcification of tissue remains a mystery for the most part; however, it has previously been shown that various factors including calcium metabolism the present invention, porcine heart valves or pericardinal tissue which was fixed in glutaraldehyde and subsequently treated with a surfactant was implanted subcutaneously in rabbits. This treated tissue unexpectedly and beneficially effected a sustained mitigation or reduction of calcification after implantation. This sustained mitigation of calcification provides a method of increasing the durability of implanted tissue, particularly of heart valve bioprostheses.
In accordance with the present invention, the tissue may be stored and processed in conventional well-known conditions and may be fixed (tanned) conventionally in from about 0.2 to about 0.6 weight percent and preferably from about 0.5 to about 0.7 weight percent glutaraldehyde in either phosphate-buffered solutions, or phosphate-free buffers as described hereinafter. The tissue handling conditions as conventionally known are not considered part of our present invention unless otherwise stated. Likewise, tissue may be sterilized in 0.625 percent glutaraldehyde or from about 4 to about 5 percent formaldehyde.
Organic surfactants within the scope of the present invention include anionic, cationic, and nonionic surfactants and their salts. Preferred salts of the surfactants in the present invention include sodium, potassium, ammonium, and halide. Anionic surfactants of the present invention are those having a relatively large hydrophobic region of hydrocarbon residues including both aliphatic groups, aromatic groups and combinations thereof bonded to a negatively charged ionic group. The aliphatic residues may be branched chains, straight chains, cyclic, heterocyclic, saturated or unsaturated. These hydrophobic residues may either be connected directly to an anionic group such as carboxylate, sulfate, or sulfonate; or connected thereto through an intermediate linkage such as an ester, amide, sulfonamide, ether, or aryl group. Anionic surfactants in one embodiment of the present invention are those having carboxylates bonded to the alkyl side chain of a steroid or through amino acids in the side chain; such as in the bile acids. Illustrative bile acids in accordance with the present invention include but are not limited to deoxycholic acid, cholic acid, lithocholic acid, taurocholic acid, and glycocholic acid, and their salts. A preferred bile acid and its salt which we have found effective in mitigation of calcification of implanted tissue is sodium deoxycholate. Anionic surfactants in accordance with the present invention further include those having a carboxylate group bonded to a straight-chained aliphatic group preferably having from about 8 to about 20 carbon atoms; such as the sodium salts of fatty acids. Anionic surfactants containing carboxylate groups in accordance with the pesent invention further include those having the carboxylate group coupled to a hydrophobic portion through an amide, sulfonamide, or ester linkage such as in the N-alkanoyl amino acids and N-acylated amino acids. Illustrative of N-alkanoyl amino acids are those including but not limited to surfactants having the formula R 1 CONR 2 CHR 3 CO 2 -- where R 1 is an aliphatic residue preferably having from about 8 to about 18 carbon atoms, R 2 is hydrogen or methyl, and R 3 is a conventional amino acid side chain. Illustrative side chains include the nonpolar aliphatic side chains of alanine, leucine, isoleucine, valine, and proline; the aromatic rings of phenylalanine and tryptophan; the polar side chains of glycine, serine, threonine, cystine, and the like; and the charged polar groups of aspartic acid, glutamic acid, lysine, and the like. Preferred carboxlate containing surfactants in accordance with this embodiment of the present invention are those containing an amide linkage such as N-lauroylsarcosine.
Anionic surfactants in accordance with an alternate embodiment of the present invention include ethylene oxide modified sulfates of aliphatic alcohols, sulfated ethanol amides, or alkyl phenols such as the sulfonated alkylphenyl ethers. Further anionic surfactants include alkane sulfonic acids and alkylaryl sulfonic acids. Alkane sulfonic acids in accordance with the present invention include those having the sulfur directly attached to the hydrophobic residue, such as 1-decanesulfonic acid; or coupled through an ester, amide, or ether; such as N-methyltaurine. Alkylaryl sulfonates are those having the sulfur directly attached to an aromatic ring such as phenyl or napthyl which is, in turn, coupled to the hydrophobic residue preferably having from about 8 to about 18 carbon atoms. Illustrative of this latter type of surfactant is dodecylbenzenesulfonic acid.
Cationic surfactants in accordance with the present invention include alkyl quaternary amines and their halide slats. Preferable surfactants in the present invention include the chloride and bromide salts of tertiary amines connected directly to a hydrophobic residue or connected thereto through an amide linkage. Preferably the amines are directly connected to a relatively large hydrophobic portion having an aromatic residue such as benzene, pyridine or napthylene; aliphatic chain which is branched, unbranched, cyclic, saturated, or unsaturated; or a combination of both aromatic and aliphatic residues. Illustrative alkyl quaternary ammonium surfactants include but are not limited to cetylpyridinium chloride, cetyltrimethylammonium bromide, trimethylphenylammonium chloride, decytrimethylammonium bromide, hexdecyltrimethylammonium bromide, and the like.
Nonionic surfactants in accordance with the present invention include polyoxyalkylene ethers, polyoxyalkylene alkylaryl ethers, aliphatic esters, polyethers, polyoxyalkylene ester derivatives, saccharide ester derivatives, and combinations thereof. Nonionic polyoxyalkylene, and preferably polyoxyethylene, ethers are those having a relatively long hydrophobic residue and a hydroxyl end connected by one or more alkylene oxide residues. Examples of polyoxyalkylene ethers are polyoxyethylene lauryl ether (Brij), polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, and the like. Nonionic polyoxyalkylene, and preferably polyoxyethylene, alkylaryl ethers are those having a relatively large hydrophobic residue and a hydroxyl end connected thereto by an aryl, such as benzene or napthaline and one or more alkylene oxide residues. Examples of polyoxyalkylene alkylaryl ethers include polyethylene Glycol p-Isooctyl phenyl ethers such as Triton X-100 and the like. Nonionic polyethers are those having the formula CH 3 (CH 2 ) N --O--(C 2 H 4 O) M where N is about 11, and M is about 23.
Nonionic aliphatic esters include aliphatic fatty acid esters, polypropyleneglycol fatty acid esters such as propyleneglycol monostearate, and glycerol fatty acid esters such as glycerol monostearate. Aliphatic fatty acid esters are those having the formula R 4 COOR 5 where R 4 is an alkyl preferably having from about 8 to about 20 carbon atoms, and R 5 is an aliphatic residue having from 1 to about 5 carbon atoms. Saccharide and polyoxyalkylene ester derivatives are those having either a 5 or 6 carbon sugar in the former or a polyoxyalkylene chain in the latter coupled to a relatively long hydrophobic residue through an ester bond. Illustrative saccharide derivatives include sorbitol coupled to fatty acids to form surfactants such as sorbitan trioleate, sorbitan strearate, sorbitan monooleate, and the like. Polyoxyalkylene ester derivatives include polyoxyethylene monooleate, polyoxyethylene monostearate, and the like. Combinations of polyoxyalkylene ether derivatives and sorbitol ester derivatives found to be useful in the present invention include Polyoxyethylene sorbitan fatty acid derivatives such as polyoxyethylene (20) sorbitan monooleate (Polysorbate-80, Tween-80 manufactured by DIFCO).
In accordance with the present invention, the effective concentration of surfactant will vary somewhat depending on the molecular weight thereof; and is preferably from about 0.1 to about 10 percent (w/v) and more preferably from about 0.5 to about 5 percent. Most preferably, the surfactant concentration is from about 0.5 to about 1.5 percent. Moreover, the treatment of the tissue with surfactant can be performed during the fixation (tanning) process, during the sterilization process, or in a separate step after fixation and prior to sterilization; and from about 2 to about 30 hours and preferably from about 6 to about 24 hours.
In accordance with a preferred embodiment of the present invention, the tissue is treated with surfactant at temperatures of from about 20° C. to about 40° C. In one embodiment, the surfactant is included in the sterilization step whose effectiveness has been found to be enhanced at temperatures above room temperature (20° C.) to a range of from about 30° to 40° C.
In accordance with the present invention, it is preferable to store, fix, and sterilize the tissue within a tissue-stabilizing pH range; that is, within a pH range that is not deleterious to the tissue components. A preferred pH range is from about 7.0 to about 7.6, and a more preferred pH range is from about 7.1 to about 7.4. The most preferred pH in accordance with the present invention is 7.3.
Buffers used in accordance with one embodiment of the present invention are preferably stable, non-interacting with the stabilization process, and have a buffering capacity sufficient to maintain an acceptable pH, particularly during the fixation of the tissue. The choice of the appropriate buffer, and its concentration will depend upon specific tissue preparation conditions; variations of which have been introduced by several manufacturers. The buffers can be either conventional 0.01-0.02M phosphate-buffered saline (PBS) or phosphate-deficient solutions such as those containing less phosphate than these 0.01 to 0.02M PBS solutions, and preferably less than about 0.001 to about 0.002M phosphate. Preferred buffers in accordance with the present invention include borate, carbonate, bicarbonate, cacodylate (found to be nontoxic in animals), and other synthetic, artificial, or organic buffers such as HEPES, N-2-hydroxyethylpiperazine-N'-2-ethanesulphonic acid; MOPS, 2-(N-morpholino) propane-sulfonic acid; and PIPES, 1,4-piperazinediethanesulphonic acid.
Preferably, the buffered or unbuffered solutions, used in accordance with the present invention should not interfere with the tissue stabilizing process afforded by fixing agents such as glutaraldehyde. That is, they should not react with the fixing agent or prevent the fixing agent from achieving proper fixation of the tissue. Illustrative of this are buffers containing primary and secondary amines such as tris(hydroxymethyl)aminomethane (Tris), which are known to react with the aldehyde groups of glutaraldehyde or formaldehyde and thus interfere with the normal tissue stabilization process.
The present invention is further illustrated by the following examples which are not intended to be limiting:
EXAMPLE I
Extracted porcine aortic heart valve tissue was thoroughly rinsed and shipped in an isotonic (285±15 milliosmols) solution of 0.02M phosphate-buffered saline (0.885 weight percent sodium chloride) at pH 7.3 and at about 4° C.; and fixed in 0.625 weight percent glutaraldehyde in an isotonic phosphate-buffered solution at pH 7.4 and at room temperature.
EXAMPLE II
Extracted porcine aortic heart valve tissue was thoroughly rinsed and shipped in an isotonic (285±15 milliosmols) solution containing 0.54 grams/liter of the sodium salt of N-2-hydroxyethylpiperazine-N'-2-ethanesulphonic acid (HEPES) and 0.885 weight percent sodium chloride at pH 7.3 at about 4° C.; and fixed with 0.625 weight percent glutaraldehyde in an isotonic solution containing 5.39 grams/liter of the sodium salt of HEPES (0.02M), 0.440 weight percent sodium chloride and 2.6 grams/liter of MgCl 2 .6H 2 O at room temperature.
EXAMPLE III
The extracted tissue of Example I was further sterilized in a 0.02M phosphate-buffered saline (0.885 weight percent sodium chloride) solution (3 square inches of tissue in 70 ml) containing 4±0.4 percent sorbitan mono-oleate polyoxyethylene (Tween-80), pH 7.3 at 35° C. The tissue was removed from the solution after 24 hours, rinsed 4 times with 0.625 percent glutaralde diseases, age, diet, degeneration of tissue components such as collagen, and turbulance are all involved to a certain extent. Recently, the occurrence of a specific calcium-binding amino acid (gamma carboxyglutamic acid), laid down after implantation of glutaraldehyde-preserved porcine xenografts, has been demonstrated; and it has been postulated to play a role in calcification. While calcification has been accompanied by degradative changes in the glutaraldehyde-treated collagen fibers of the implanted tissue, it remains unclear whether the dystrophic clacification is a cause or the result of tissue degeneration. Nevertheless, there has been a continued effort to elucidate the source of the calcification problem with implanted tissue.
In accordance with the present invention, we have developed a process which effectively reduces calcification of implanted biological tissue, and mantains the proper hemodynamic properties of the valve leaflets in bioprosthetic heart valves. This process advantageously reduces the tendency of bioprostheses toward calcification and overcomes some of the problems associated with the durability of xenograft heart valves.
SUMMARY OF THE INVENTION
In accordance with the present invention, disclosed is an improved process for treating biological tissue prior to implantation which results in a mitigation or reduction of calcification thereof after implantation. The process comprises contacting the biological tissue with a surfactant in an amount effective in reducing calcification of said tissue after implantation.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the present invention, it is contemplated that various types of implantable biological tissue derived from numerous animal sources and parts of the anatomy can be made resistant to calcification. Thus, the tissue can be derived from various sources such as but not limited to bovine, porcine, horse, sheep, kangaroo, or rabbit; and can include tendons, ligaments, heart valves, or tissue used to construct heart valves such as dura mater and pericardium. It is further contemplated that tissue used for augmentation such as skin patches, pericardial patches, aortic patches, and tympanic membranes is suitable in the present invention. In accordance with a preferred embodiment of hyde in 0.02M phosphate-buffered saline for 10 minutes each and implanted subcutaneously in growing rabbits. The valve tissue was retrieved up to six weeks later at regular one-week intervals. After retrieval, the extent of tissue calcification was assessed by quantitatively monitoring the weight percent calcium in dried tissue using atomic absorption analysis; and histologically by visually monitoring the degree of calcificaton in Von Kossa-stained tissue sections. Both the histologic and quantitative results indicate that the implanted valve tissue effected a significant reduction in calcification compared to a valve tissue treated identically to that described herein in all essential details with the exception that no Tween-80 was added.
EXAMPLE IV
The extracted tissue of Example II was further sterilized in a 0.02M HEPES (5.39 gram/liter of the sodium salt) buffered saline solution (3 square inches of tissue in 70 ml) containing 4±0.4 percent formaldehyde, 22.5 percent ethanol, 0.26 grams/liter MgCl 2 .6H 2 O, at pH 7.3 and 35° C. The tissue was removed from the solution after 24 hours, rinsed 4 times with 0.625 percent glutaraldehyde in 0.02M HEPES-buffered saline for 10 minutes each, and implanted subcutaneously in growing rabbits. The valve tissue was retrieved up to six weeks later at regular one-week intervals. After retrieval, the extent of tissue calcification was assessed by quantitatively monitoring the weight percent calcium in dried tissue using atomic absorption analysis; and histologically by visually monitoring the degree of calcification in Von Kossa-stained tissue sections. The results of the histologic and quantitative analyses were used for comparison with results obtained for tissue treated with various surfactants.
EXAMPLE V
The extracted tissue of Example II was further sterilized in a 0.02M HEPES (5.39 gram/liter of the sodium salt) buffered saline solution (3 square inches if tissue in 70 ml) containing 4±0.4 percent formaldehyde, 22.5 percent ethanol, 11.3mM (1.5 weight percent) sorbitan monooleate polyoxyethylene (Tween-80), 0.26 grams/liter MgCl 2 .6H 2 O, at pH 7.3 and 35° C. The tissue was removed from the solution after 24 hours, rinsed 4 times with 0.625 percent glutaraldehyde in 0.02M HEPES-buffered saline for 10 minutes each, and implanted subcutaneously in growing rabbits. The valve tissue was retrieved up to six weeks later at regular one-week intervals. After retrieval, the extent of tissue calcification was assessed by quantitatively monitoring the weight percent calcium in dried tissue using atomic absorption analysis; and histologically by visually monitoring the degree of calcification in Von Kossa-stained tissue sections. Both the histologic and quantitative results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE VI
The extracted tissue of Example II was treated identically to that of Example V in all essential details with the exception that no ethanol was added. After sterilization and rinsing the tissue was implanted in growing rabbits and retrieved up to six weeks later at regular one-week intervals. After retrieval, the extent of tissue calcification was assessed by quantitatively monitoring the weight percent calcium in dried tissue using atomic absorption analysis; and histologically by visually monitoring the degree of calcification in Von Kossa-stained tissue sections. Both the histologic and quantitative results indicate that there was no effect of the presence of ethanol in the surfactant solution on mitigating calcification.
EXAMPLE VII
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 24.0mM Triton X-100 (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE VIII
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 57.2 mM 1-decanesulfonic acid (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE IX
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 45.9 mM dodecylbenzenesulfonic acid (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE X
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 42 mM potassium coconut fatty acid hydrolyzed protein (Maypon-4C) (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE XI
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 55.3 mM N-lauroylsarcosine (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE XII
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 36.2 mM deoxycholic acid (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE XIII
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 53.5 mM decyltrimethylammonium bromide (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE XIV
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 41.2 hexadecyltrimethylammonium bromide (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance wth Example IV which did not include surfactant.
EXAMPLE XV
The extracted tissue of Example II was treated, implanted in growing rabbits, and analyzed identically to that of Example V in all essential details with the exception that 87.4 trimethylphenylammonium chloride (1.5 weight percent) was used in place of Tween-80. The results indicate that the implanted valve tissue effected a significant reduction in calcification compared to the valve tissue treated in accordance with Example IV which did not include surfactant.
EXAMPLE XVI
The tissue treated in accordance with the process of Example III was further analyzed to assess the integrity of the tissue after exposure to surfactant. The results of our analysis show that there was no significant difference in the cross-link stability as indicated by shrinkage temperature, tissue stability as indicated by pronase digestion; amino acid analysis, ninhydrin analysis; uronic acid content, histologic examination as indicated by staining with Hematoxylin Eosin, aldehyde fuschin, PAS/alcian blue, and Trichrome; and surface morphology as determined by scanning electron microscopy and transmission electron microscopy.
The present invention has been described in specific detail and in reference to its preferred embodiments; however, it is to be understood by those skilled in the art that modifications and changes can be made thereto without departing from the spirit and scope thereof. | A process for the preparation of implantable biological tissue, and in particular bioprosthetic heart valves, which are prone to calcification after implantation. The process includes the treatment of tissue with an effective amount of a surfactant to reduce calcification of the implanted tissue. | 8 |
The present utility application hereby formally claims priority of currently U.S. Provisional Patent application No. 61/852,351 filed Mar. 15, 2013 on a “Head-of-Wall Firestopping Insulation Construction For Positioning In Engagement With A Fluted Deck Thereabove” filed by same inventor as listed herein, namely, James P. Stahl Jr., and assigned to the same assignee as listing herein, namely, Specified Technologies Inc., and said referenced provisional application is hereby formally incorporated by reference as an integral part of the present application.
The present utility application hereby also formally claims priority of currently U.S. Provisional Patent application No. 61/957,632 filed Jul. 8, 2013 on a “Head-of-Wall Firestopping Insulation Construction For Positioning In Engagement With A Fluted Deck Thereabove” filed by the same inventor as listed herein, namely, James P. Stahl Jr., and assigned to the same assignee as listing herein, namely, Specified Technologies Inc., and said referenced provisional application is hereby formally incorporated by reference as an integral part of the present application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention deals with the field related to a method of sealing the top track, that is, the ceiling runner channel with respect to a wall prior to or subsequent to the insulation of the wall studs and gypsum board extending thereover. Sealing of this area is normally more difficult after the studs and gypsum board have been placed and the wall construction is fully assembled in place. However, the insulation system of the present invention can be installed before the wall and ceiling constructions of a building are built or can be stall after initial installation thereof as an after-market add-on to the initial construction. Currently, the primary system used for insulating such head-of-wall areas immediately below fluted steel decks is to simply apply a firestopping gasket system on top of the track and securing it to the bottom of the floor thereabove. This construction is an excellent solution for flat concrete slabs, but for ceilings that include a fluted deck which define ceiling runner channels facing downwardly, it is necessary to include an additional firestopping pillow positioned in each of the flute areas above a wall which is packed into the void area therein seal the head-of-wall-area for achieving firestopping between the wall structure and the fluted deck thereabove. Such ceiling runner channels will conventional have a generally trapezoidal cross-sectional shape in the flute recesses thereof. This conventional solution is time consuming, labor intensive and a better firestopping insulation system is currently needed. This need is filled by the system of the present invention.
2. Description of the Prior Art
Many patents have been issued for head-of-wall firestopping constructions which are designed to mate with a fluted steel deck thereabove in various manners such as shown in U.S. Pat. No. 4,106,249 patented Aug. 15, 1978 to Virgil R. Morton and assigned to Verco Manufacturing, Inc. on a “Method and Apparatus For Interlocking and Venting a Structural Diaphragm”; and U.S. Pat. No. 4,114,335 patented Sep. 19, 1978 to Frank E. Carroll and assigned to Carroll Research, Inc. on a “Sheet Metal Structural Shape And Use In Building Structures”; and U.S. Pat. No. 4,274,239 patented Jun. 23, 1981 to Frank E. Carroll and assigned to Carroll Research, Inc. on a “Building Structure”; and U.S. Pat. No. 4,351,870 patented Sep. 28, 1982 to Edgar English, Jr. on “Maximized Strength-To-Weight Ratio Panel Material”; and U.S. Pat. No. 4,507,901 patented Apr. 2, 1985 to Frank E. Carroll on a “Sheet Metal Structural Shape And Use In Building Structures”; and U.S. Pat. No. 4,619,471 patented Oct. 28, 1986 to Gerold J. Harbeke on an “Embedded Pipe Coupling Holder”; and U.S. Pat. No. 5,001,883 patented Mar. 26, 1991 to Hugo A. J. Landheer and assigned to Hunter Douglas International N.V. on a “Sandwich Panel For Ceiling Application”; and U.S. Pat. No. 5,293,724 patented Mar. 15, 1994 to Kenneth R. Cornwall on a “Coupling Assembly For Corrugated Decks And Method For Connecting Thereto”; and U.S. Pat. No. 5,755,066 patented May 26, 1998 to Duane William Becker on a “Slip Track Assembly”; and U.S. Pat. No. 5,913,788 patented Jun. 22, 1999 to Thomas R. Herren on a “Fire Blocking And Seismic Resistant Wall Structure”; and U.S. Pat. No. 6,058,668 patented May 9, 2000 to Thomas R. Herren on a “Seismic And Fire-Resistant Head-Of-Wall Structure”; and U.S. Pat. No. 6,216,404 patented Apr. 17, 2001 to Timothy Vellrath on a “Slip Joint And Hose Stream Deflector Assembly”; and U.S. Pat. No. 6,698,146 patented Mar. 2, 2004 to Michael D. Morgan et al and assigned to W.R. Grace & Co.-Conn on “In Situ Molded Thermal Barriers”; and U.S. Pat. No. 7,043,880 patented May 16, 2006 to Michael D. Morgan et al and assigned to W. R. Grace & Co.-Conn on “In Situ Molded Thermal Bathers”; and U.S. Pat. No. 7,617,643 patented Nov. 17, 2009 to Don A. Pilz et al and assigned to California Expanded Metal Products Company on a “Fire-Rated Wall Construction Product”; and U.S. Pat. No. 7,775,006 patented Aug. 17, 2010 to Konstantinos Giannos on a “Fire Stop System For Wallboard And Metal Fluted Deck Construction”; and U.S. Pat. No. 7,841,148 patented Nov. 30, 2010 to Timothy D. Tonyan et al and assigned to United States Gypsum Company on “Non-Combustible Reinforced Cementitious Lightweight Panels And Metal Frame System For Roofing”; and U.S. Pat. No. 7,849,648 patented Dec. 14, 2010 to Timothy D. Tonyan et al and assigned to United States Gypsum Company on “Non-Combustible Reinfored Cementitious Lightweight Panels And Metal Frame System For Flooring”; and U.S. Pat. No. 7,950,198 patented May 31, 2011 to Don A. Pilz et al and assigned to California Expanded Metal Products Company on a “Fire-Rated Wall Construction Product”; and U.S. Pat. No. 8,001,737 patented Aug. 23, 2011 to Darrell W. Price and assigned to Mhubbard 09, LLC on “Corrugated Deck Sealing Devices, Apparatus, Systems And Methods Of Installation”; and U.S. Pat. No. 8,065,852 patented Nov. 29, 2011 to Timothy D. Tonyan et al and assigned to U.S. Gypsum Company on “Non-Combustible Reinforced Cementitious Lightweight Panels And Metal Frame System For Roofing”; and U.S. Pat. No. 8,069,633 patented Dec. 6, 2011 to Timothy D. Tonyan et al and assigned to U.S. Gypsum Company on “Non-Combustible Reinforced Cementitious Lightweight Panels And Metal Frame System For Flooring”; and U.S. Pat. No. 8,074,412 patented Dec. 13, 2011 to Thomas Gogan et al on a “Fire And Sound Resistant Insert For A Wall”; and U.S. Pat. No. 8,087,205 patented Jan. 3, 2012 to Don A. Pilz et al and assigned to California Expanded Metal Products Company on a “Fire-Rated Wall Construction Product”; and U.S. Pat. No. 8,181,404 patented May 22, 2012 to James Alan Klein on “Head-Of-Wall Fireblocks And Related Wall Assemblies”; and United States Patent Publication No. 2009/0223159 published Sep. 10, 2009 to Mark Colon on a “Firestop Block And Thermal Barrier System For Fluted Metal Decks”; and United States Publication No. 2011/0185656 published Aug. 4, 2011 to James A. Klein on a “Fire Retardant Cover For Fluted Roof Deck; and United States Patent Publication No. 2011/0314757 published Dec. 29, 2011 to Don A. Pilz et al and assigned to California Expanded Metal Products Company on a “Fire-Rated Wall And Ceiling System”.
SUMMARY OF THE INVENTION
The present invention provides a unique construction for head-of-wall firestopping which is usable with a specific configuration of the ceiling. Many ceilings in various building constructions include a fluted ceiling deck which includes usually a plurality of ceiling runner channels extending thereacross with recessed areas defined therein facing downwardly having a generally trapezoidal cross section. Each of the ceiling runner channels will include an upper recessed panel extending approximately horizontally and a first recess side panel engaging the upper recess panel and extending downwardly and outwardly with respect thereto. Also included will be a second recess side panel engaging the upper recess panel at a position spatially disposed from the first recess side panel and extending downwardly and outwardly from the upper recess panel in a direction extending away from the first recess side panel.
The wall construction with which the head-of-wall firestopping apparatus of the present invention is usable is generally included extending vertically and is positioned immediately below the head-of-wall area and is defined by a plurality of wall studs with a first gypsum board construction attached on one side thereof and a second gypsum board construction attached on the other side thereof normally spatially disposed from the first gypsum board construction.
The head-of-wall firestopping construction will preferably include a first insulation member of fire insulating material positioned extending into the recessed area defined in the ceiling such as to in frictional engagement with respect to the fluted ceiling deck and extending downwardly therefrom into the head-of-wall area. This insulation member will preferably include a first upper insulation section formed of fire insulating material such as resin-impregnated moldable mineral wool or fiber. The first upper insulation section will extend into the recessed area defined above into a ceiling runner channel in the ceiling above and will abut with respect to the fluted ceiling deck in the recessed areas thereof. This first upper insulation section will preferably include a first upper insulation horizontal surface defined extending approximately horizontally therein. The first upper insulation section will further include a first upper insulation primary incline surface attached to the first upper insulation horizontal surface and extending downwardly and outwardly therefrom. The first upper insulation primary inclined surface will be positioned in abutment with respect to a first recess side panel for facilitating frictionally movable attachment with respect thereto.
The first upper insulation section will further include a first upper insulation sectionary inclined surface attached to the first upper insulation horizontal surface at a position spatially disposed from the first upper insulation primary inclined surface and extending downwardly and outwardly therefrom. The first upper insulation secondary inclined surface will preferably be positioned in abutment with a second recess side panel for facilitating frictionally movable attachment with respect thereto. The first upper insulation section will further include a first upper insulation exterior surface extending generally vertically and facing outwardly with respect to the head-of-wall area above the first gypsum board construction.
The first insulation member will also include a first lower insulation section of fire insulating material attached to the first upper insulation section and extending downwardly therefrom to a position in abutment with and extending over the first gypsum board construction for firestopping thereadjacent. The first lower insulation section will preferably define a first lower insulation exterior surface extending generally vertically and facing outwardly from the head-of-wall area. The head-of-wall insulation construction will further include a second insulation member also formed of a fire resistant material such as resin-impregnated moldable mineral wool or fiber. The second insulation member will be positioned to extend into a recessed area defined in the ceiling such as to be in frictional engagement with respect to the fluted ceiling deck and extending downwardly therefrom into the head-of-wall area. The insulation member will preferably include a second upper insulation section of fire insulating material extending into a recessed area defined thereabove in a ceiling runner channel in the ceiling into abutment with respect to the fluted ceiling deck and the recessed area thereof. The first upper insulation section will further include a second upper insulation horizontal surface defined extending approximately horizontally thereon. Second upper insulation section will also include a second upper insulation primary inclined surface attached to the second upper insulation surface horizontal surface and extending downwardly and outwardly therefrom. The second upper insulation primary inclined surface will preferably be positioned in abutment with a first recessed side panel for facilitating frictionally engagement with respect thereto. The second upper insulation section will further include a second upper insulation secondary inclined surface attached to the second upper insulation surface at a position spatially disposed from the second upper insulation primary inclined surface and extending downwardly and outwardly therefrom. The second upper insulation secondary inclined surface will be positioned in abutment with the second recess side panel for facilitating frictionally movable attachment with respect thereto. Further included will be a second upper insulation exterior surface defined extending generally vertically and facing outwardly with respect to the head-of-wall area positioned extending outwardly and above the second gypsum board construction. The second insulation member will further include a second lower insulation section of fire insulating material attached to the second upper insulation section at a position spatially disposed from the first lower insulation section and extending downwardly therefrom to a position in abutment with and extending over the second gypsum wall board construction for firestopping thereadjacent. The second lower insulation section will define a second lower insulation exterior surface extending generally vertically and facing outwardly from the head-of-wall area. Furthermore the head-of-wall firestopping insulation will include a first cover attached to the first insulation member and positioned extending at least partially across the first upper insulation exterior surface and at least partially across the first lower insulation exterior surface for enhancing firestopping of the first insulation member. Furthermore a second cover will preferably be included attached to the second insulation member and positioned extending at least partially across the second upper insulation exterior surface and at least partly across the second lower insulation exterior surface for the purpose of enhancing the firestopping capabilities of the second insulation member.
Alternatively, the construction of the present invention can combine the first insulation member and the second insulation member together as a single integral unit to form a single piece head-of-wall firestopping component with a single upper insulation section and a first and second lower insulation section which extend downwardly over the outer facings of the first and second gypsum board construction of the wall construction.
It is an object of the present invention to provide a head-of-wall firestopping insulation construction which can be used in engagement with a fluted deck thereabove for firestop sealing thereagainst.
It is an object of the present invention to provide a head-of-wall firestopping construction which can include an intumescent or non-intumescent firestopping material such as mineral wool to effectively seal the head-of-wall area.
It is an object of the present invention to provide a head-of-wall firestopping construction which is of simple effective construction and has a minimum number of moving parts.
It is an object of the present invention to provide a head-of-wall firestopping construction which is easily and inexpensively maintained.
It is an object of the present invention to provide a head-of-wall firestopping construction which has minimal maintenance requirements.
It is an object of the present invention to provide a head-of-wall firestopping construction which can effectively seal the undersurface of ceiling decks which have convoluted configurations such as those including ceiling runner channels having trapezoidally-shaped cross-sections
It is an object of the present invention to provide a head-of-wall firestopping construction which can achieve effective insulation with conventional insulating material such as mineral wool and/or ceramic fiber.
It is an object of the present invention to provide a head-of-wall firestopping construction which includes a separate section of the assembly which projects vertically down to cover the open top of the joint, but not within it, and in this manner allow for the joint to move up and down due to normal deflections without distressing the material within the joint or encumbering the amount of movement.
It is an object of the present invention to provide a head-of-wall firestopping construction which maintains the insulating material encapsulated within an outer housing by frictional engagement within the head-of-wall area.
It is an object of the present invention to provide a head-of-wall firestopping construction which can be installed in two different ways, that is, it can either be installed immediately after the track is fastened to the underside of the deck, or it can be installed after the wall has been fully constructed, sheathed and finished.
It is an object of the present invention to provide a head-of-wall construction which allows installation persons to slide gypsum board vertically therepast during installation of the wall construction.
BRIEF DESCRIPTION OF THE DRAWINGS
While the invention is particularly pointed out and distinctly described herein, a preferred embodiment is set forth in the following detailed description which may be best understood when read in connection with the accompanying drawings, in which:
FIG. 1 is a perspective illustration of an embodiment of the head-of-wall firestopping construction of the present invention shown in position extending between a fluted ceiling deck thereabove and a wall construction therebelow;
FIG. 2 is a perspective illustration of an embodiment of a first insulation member of the head-of-wall firestopping construction of the present invention;
FIG. 3 is a side cross-sectional view of an embodiment of a first insulation member of the head-of-wall firestopping construction of the present invention;
FIG. 4 is a side cross-sectional view of an embodiment of a second insulation member of the head-of-wall firestopping construction of the present invention;
FIG. 5 is a side cross-sectional view of an embodiment of the head-of-wall firestopping construction of the present invention shown installed beneath and extending upwardly into engagement with a ceiling thereabove having a fluted ceiling deck for firestopping across the head-of-wall area thereadjacent;
FIG. 6 is a top plan view of an embodiment of a second insulation member of the head-of-wall firestopping construction of the present invention;
FIG. 7 is a perspective illustration of an embodiment of the head-of-wall firestopping construction of the present invention shown in position with multiple first insulation members positioned adjacently to firestop along a large expanse of a fluted ceiling deck positioned thereabove;
FIG. 8 is a front plan view of multiple similarly configured embodiments of the first cover of the present invention shown positioned above a wall construction therebelow;
FIG. 9 illustrates a side plan view an embodiment of a first cover of the head-of-wall firestopping construction of the present invention:
FIG. 10 is an exploded illustration of an embodiment of the head-of-wall firestopping construction of the present invention shown with the first insulation member and the second insulation member displaced laterally outwardly for purposes of illustration;
FIG. 11 is a side cross-sectional view of an embodiment of the head-of-wall firestopping construction of the present invention shown positioned for firestopping within the head-of-wall area between the wall construction therebelow and the fluted ceiling deck thereabove;
FIG. 12 is a perspective illustration of an alternative embodiment of the head-of-wall firestopping construction of the present invention which includes a construction wherein the first upper insulation member and the second upper insulation member are formed as a single unitary upper insulation member extending upwardly from a first lower insulation section and a second lower insulation section adjacent a wall construction therebelow.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides a unique construction for an insulation means for firestop sealing in the head-of-wall area between wall construction and ceiling construction in building construction applications. Normally, this insulation means is made from a high temperature insulating material such as mineral wool or ceramic fiber and can possibly be intumescent, but need not be.
The present invention provides a conveniently usable configuration for a head-of-wall firestopping construction which preferably includes a first insulation member 80 having a first upper insulation section 82 and a first lower insulation section 44 . It also includes a second insulation member 100 having a second upper insulation section 102 and a second lower insulation member 54 . These two insulation member 80 and 100 are designed to seal each side of a head-of-wall area 25 and extend from a position adjacent the gypsum board construction of the wall construction 13 upwardly into recessed areas 15 defined in ceiling runner channels 11 within a fluted ceiling deck 10 of a ceiling 12 thereabove. By sealing each lateral side of the head-of-wall area 25 effective firestopping is achieved.
The firestopping construction of the present invention is usable for sealing a head-of-wall area which is defined below a ceiling 12 which includes fluted ceiling deck 10 and at least one or more ceilings runner channels 11 extending therethrough which define recessed areas 15 therein facing downwardly toward the head-of-wall area 25 therebelow. The ceiling runner channels 11 will preferably include upper recess panels 16 extending generally horizontally therewithin. The ceiling runner channels 11 will include not only the generally horizontally extending upper recess panel 16 but also a first recess side panel 18 engaging the upper recess panel 16 and extending downwardly and outwardly therefrom. Also included within the ceiling runner channel 11 will be a second recess side panel 20 engaging the upper recess panel 16 at a position spatially disposed from the first recess side panel 18 and extending downwardly and outwardly from the upper recess panel 16 in a direction extending away from the first recess side panel.
The wall construction 13 which is positioned immediately below the head-of-wall area 25 will include a plurality of wall studs 23 which will usually be steel but can be made of any material particularly wood but usually steel and will include a first gypsum board construction 24 attached thereto and a second gypsum board construction 26 attached thereto oppositely positioned from the board construction 24 .
The head-of-wall firestopping construction usable in a head-of-wall area positioned between such a fluted ceiling deck 10 and a wall construction 13 therebelow will preferably include a first insulation member 80 of preferably mineral wood or other fire insulating material positioned extending into a recessed area 15 defined in the ceiling 12 . It is preferably positioned in frictional engagement with respect to the fluted ceiling deck 10 and extends downwardly therefrom into the head-of-wall area 25 .
This insulation member in more detail includes a first insulation member 80 of fire resistant material or fire insulating material positioned extending into the recessed area 15 defined in the ceiling 12 in order to be in frictional engagement with respect to the fluted ceiling deck and extending downwardly therefrom into the head-of-wall area 25 . Said first insulation member 80 will include a first upper insulation section 82 of the same fire insulating material extending into the recessed area 15 defined above in a ceiling runner channel 11 in the ceiling 12 into abutment with respect to the fluted ceiling deck 10 in the recessed areas 15 thereof. The first upper insulation section 82 will include a first upper insulation horizontal surface 84 defined extending approximately horizontally thereon. Also the first upper insulation section 82 will further include a first upper insulation primary inclined surface 86 attached to the first upper insulation horizontal surface 84 and extending downwardly and outwardly therefrom. The first upper insulation primary inclined surface 86 is preferably positioned in abutment with a first recess panel 118 for facilitating frictionally movable engagement with respect thereto. The first upper insulation section 82 will further include a first upper insulation secondary inclined surface 88 attached to the first upper insulation horizontal surface 84 at a position spatially disposed from the first upper insulation primary inclined surface 86 and extending downwardly and outwardly therefrom. The first upper insulation secondary inclined surface 88 will be preferably positioned in abutment with the second recess side panel 20 for facilitating frictionally movable attachment with respect thereto. It will also include a first upper insulation exterior surface 40 extending generally vertically and facing outwardly with respect to the head-of-wall area 25 adjacent and above the first gypsum board construction 24 . The first insulation member 80 will further include a first lower insulation section 44 formed of fire insulating material such as resin-impregnated moldable mineral wool and be attached to the first upper insulation section 82 to extend downardly therefrom to a position in abutment with and extending over the first gypsum board construction 24 for firestopping thereadjacent. The first lower insulation section 44 will define a first lower insulation exterior surface 45 extending generally vertically and facing outwardly from the head-of-wall area 25 .
The head-of-wall insulation construction of the present invention will further include a second insulation member 100 which is similarly configured to the first insulation member 80 and is preferably identically configured to facilitate use and inventory control thereof. Second insulation member 100 will extend be formed of similar fire insulating materials and will be adapted to extend into recessed areas 15 defined in the ceiling 12 and will be capable of being brought into frictional engagement with respect to the fluted ceiling deck 10 and extending downwardly therefrom into the head-of-wall area 25 . The second insulation member 100 will preferably include a second upper insulation section 102 of fire insulating material which will extend into the recessed area 15 defined thereabove in a ceiling runner channel 11 in the ceiling 12 and will extend into abutment with respect to the fluted ceiling deck 10 in the recessed areas 15 . The first upper insulation section 102 will include a second upper insulation horizontal surface 104 defined extending approximately horizontally thereon. Second upper insulation section 102 will further include a second upper insulation primary inclined surface 106 attached to the second upper insulation horizontal surface 104 and oriented extending downwardly and outwardly therefrom. The second upper insulation primary inclined surface 106 will be positioned in abutment with the first recessed side panel 18 for facilitating frictional movable attachment with respect thereto. The second upper insulation section 102 will further include a second upper insulation secondary inclined surface 108 attached to the second upper insulation horizontal surface 104 at a position spatially disposed from the second upper insulation primary inclined surface 106 and oriented extending downwardly and outwardly therefrom. The second upper insulation secondary inclined surface 108 is preferably positioned in abutment with the second recessed side panel 20 for facilitating frictionally movable attachment with respect thereto.
The second upper insulation section 102 will further include a second upper insulation exterior surface 42 extending generally vertically and facing outwardly with respect to the head-of-wall area 25 and positioned extending outwardly and above the second gypsum board construction 26 . The second insulation member 100 will further include a second lower insulation section 54 of fire insulating material attached to the second upper insulation section 102 at a position spatially disposed from the first lower insulation section 44 and extending downwardly therefrom to a position in abutment with and extending over the second gypsum board construction 26 for firestopping thereadjacent. The second lower insulation section 54 will define a second lower insulation exterior surface 55 extending generally vertically and facing outwardly from the head-of-wall area 25 .
Further included in the construction of the head-of-wall area firestopping construction of the present invention is a first cover 70 which is attached to the first insulation member 80 and positioned extending at least partially across the first upper insulation exterior surface 40 and at least partially across the first lower insulation exterior surface 45 for the purpose of enhancing firestopping of first insulation member 80 . Furthermore the firestopping construction includes a second cover 72 attached to the second insulation member 100 and positioned extending at least partially across the second upper insulation exterior surface 42 and at least partially across the second lower insulation exterior surface 55 for enhancing firestopping of the second insulation member 100 . In the preferred configuration of the present invention the first insulation member 80 and the second insulation member 100 are made of a molded mineral wool material. Furthermore for enhanced firestopping it is also possible that the first cover 70 and the second cover 72 can be made of a paper material with an intumescent component impregnated therewithin to facilitate firestopping characteristics of the head-of-wall firestopping apparatus. In this embodiment the first upper insulation section 82 of the first insulation member 80 and the second upper insulation section 102 of the second insulation 100 are preferably positioned within the head-of-wall area such as to extend upwardly into a recessed area 15 to a position spatially disposed from one another to facilitate the use of head-of-wall firestopping construction of the present invention for firestopping wall constructions of various widths. As such, when positioned apart from one another the first upper insulation 82 and the second upper insulation section 102 will define a void therebetween and the lateral dimensions of this void can be varied and made larger for large walls and in this manner allow a single size and configuration of firestopping construction to be usable with walls having various thicknesses.
Also it is possible with the apparatus of the present invention that the first upper insulation section 82 of the first insulation member 80 and the second upper insulation section 102 of the second insulation member 100 can be positioned within the head-of-wall area and extended into the recessed area 15 at a position wherein they are in direct abutment with respect to one another and in this manner further enhanced firestopping within the head-of-wall area. It should be appreciated that this configuration is only for a single conventional or standard width thickness of wall. Wider thicknesses of wall will require the first upper insulation section 82 and the second upper insulation section 102 to be spaced apart from one another rather than in direct abutment with respect to one another.
In a preferred configuration of the present invention the first lower insulation section 44 will define a first lower insulation lower surface 46 facing generally downwardly. The second lower insulation section 54 will define a second lower insulation lower surface 56 facing generally downwardly therefrom. With this configuration the head-of-wall firestopping construction will further include a first lower surface lower cover 47 extending over the first lower insulation lower surface 46 . Furthermore a second lower surface lower cover 57 will be included extending over the second lower insulation surface 56 for enhancing firestopping of the first lower insulation section 44 and the second lower insulation section 54 . It is also possible that the first lower surface lower cover 47 and the second lower surface lower cover 57 will be made of a paper material impregnated with an intumescent component therein to facilitate firestopping.
With this construction the first lower insulation lower surface 46 can include a first lower insulation lower truncated surface 48 positioned immediately adjacent to the first gypsum board construction 24 and oriented inclined upwardly and inwardly with respect thereto. In this manner relative movement of the first gypsum board construction 24 upwardly during installation thereof into a position between the wall studs 23 and the first lower insulation member 44 can be enhanced due to the upwardly and inwardly directed angle of inclination of the first lower insulation lower truncated surface 48 . In a similar manner the second lower insulation lower surface 56 can define a second lower insulation lower truncated surface 58 positioned immediately adjacent to the second gypsum board construction 26 . This surface 58 will be oriented inclined upwardly and inwardly with respect to the gypsum board construction 26 to facilitate relative movement of the gypsum board construction upwardly vertically into position for installation with respect to the wall studs 23 during initial construction thereof. In this manner movement of the second gypsum board construction 26 to a position between the wall studs 23 and the second lower insulation section 54 can be facilitated.
In a further preferred configuration the first lower insulation section 44 will preferably include a first lower insulation interior surface 49 positioned immediately adjacent to and facing the first gypsum board construction 24 for the purpose of facilitating firestopping thereadjacent. In this configuration the second lower insulation section 54 will include a second lower insulation interior surface 59 positioned immediately adjacent to and facing the second gypsum board construction 24 to facilitate firestopping thereadjacent.
To facilitate firestopping by the first and second lower insulation sections 44 and 54 the firestopping construction of the present invention can include a first lower insulation interior cover 50 positioned extending over the first lower insulation interior surface 49 and adjacent to the first gypsum board construction to facilitate firestopping thereover. Further included can be a second lower insulation interior cover 60 positioned extending over the second lower insulation interior surface 59 and adjacent to the second gypsum board construction to facilitate firestopping thereover. These lower insulation interior covers 50 and 60 can be made of a paper material with an intumescent component impregnated therewithin which facilitates firestopping. Further the present invention may include a first angle bracket 51 attached to the first upper insulation section 82 and to the first lower insulation section 44 at a position adjacent to the first gypsum board construction 24 to facilitate positioning of the first insulation member 80 with respect to the head-of-wall area 25 adjacent the first gypsum board construction 24 . Additionally a second angle bracket 61 can be included attached to the second upper insulation section 102 and attached to the second lower insulation section 54 at a position adjacent the second gypsum board construction 26 to facilitate positioning of the second insulation 100 with respect to the head-of-wall area 25 adjacent the second gypsum board construction 26 .
The first insulation member 80 and the second insulation member 100 are preferably both formed of a resin-impregnated mineral wool or fiber which is formable.
One of the preferred configurations of the present invention is shown in FIG. 12 wherein the first upper insulation section 82 and the second upper insulation section 102 are formed as a single member which is defined in the figures herein as an upper insulation section 30 . This single firestopping construction will effectively seal both sides of the head-of-wall area simultaneously by placement of a single fixture. It is designed to be used below a ceiling 12 which includes a fluted ceiling deck 10 which defines at least one ceiling runner channel 11 therein with recessed areas 15 facing downwardly toward the head-of-wall area 25 therebelow. The ceiling runner channels 11 will include upper recess panels 16 extending generally horizontally and including a first recess side panel 18 engaging the upper recess panels 16 and extending downwardly and outwardly therefrom and including a second recess side panel 20 engaging the upper recess panel 16 at a position spatially disposed from the first recess side panel 18 and extending downwardly and outwardly from the upper recess panel 16 in a direction extending away from the first recess side panel. This configuration for the fluted ceiling deck 10 will be positioned above the head-of-wall area 25 . Below the head-of-wall area 25 the wall construction 13 will be defined extending generally vertically and will include a plurality of wall studs 23 of wood, metal or other material with a first gypsum board construction 24 extending along one face thereof and second gypsum board construction 26 extending across the opposite face therefrom. The head-of-wall firestopping construction usable with this embodiment of the present invention will include an insulation member of fire insulating material positioned extending into a recessed area 15 defined in the ceiling 12 and will be in frictional engagement with respect to the fluted ceiling deck 10 and will extend downwardly therefrom into the head-of-wall area 25 therebelow. The insulation member 28 will include an upper insulation section of fire insulating material extending into the recessed area 15 defined thereabove in a ceiling runner channel 11 in a ceiling 12 into abutment with respect to the fluted ceiling deck 10 in the recessed area 15 thereof. The upper insulation section 30 will include an upper insulation horizontal surface 32 defined extending approximately horizontally thereon. Upper insulation section 30 will further define an upper insulation primary inclined surface 34 attached to the upper insulation horizontal surface 32 and extending downwardly and outwardly therefrom. The upper insulation primary inclined surface 34 will be positioned in abutment with a first recess side panel 18 for facilitating frictionally movable attachment with respect thereto.
Upper insulation section 30 will further include an upper insulation secondary inclined surface 38 attached to the upper insulation horizontal surface 32 at a position spatially disposed from the upper insulation primary inclined surface 34 and extending downwardly and outwardly therefrom. The upper insulation secondary inclined surface 38 will be positioned in abutment with a second recess side panel 20 for facilitating frictionally movable attachment with respect thereto. Upper insulation section 30 will further include a first upper insulation exterior surface 40 extending generally vertically and facing outwardly with respect to the head-of-wall area 25 above the first gypsum board construction 24 . Also included will be a second upper insulation exterior surface 42 extending generally vertically and facing outwardly with respect to the head-of-wall area 25 positioned extending outwardly and above the second gypsum board construction 26 .
The head-of-wall area firestopping construction will include a first cover 70 attached to the insulation member 28 and positioned extending at least partially across the first upper insulation exterior surface 40 and extending at least partially across the first lower insulation exterior surface 45 for enhancing firestopping by the insulation member 28 . Further included in the construction of the head-of-wall firestopping device will be a second cover 72 attached to the insulation member 28 and positioned extending at least partially across the second upper insulation exterior surface 42 and extending at least partially across the second lower insulation exterior surface 55 for enhancing firestopping of the insulation member 28 .
One of the important characteristics of the present invention is the including of male and female overlapping sections which will enhance the finished appearance and securement of this configuration of the head-of-wall firestopping construction of the present invention with respect to the portions of the ceiling 12 and wall construction 13 immediately thereadjacent. These overlapping sections are shown in various drawings including FIG. 2 which shows the extended portion 64 in the righthand portion of the drawings and the reduced section 64 . As such, the seams defined in the lower insulation members will not align with the seams of the covers 70 and 72 . See also FIG. 7 which shows similar overlapping panels 64 .
While particular embodiments of this invention have been shown in the drawings and described above, it will be apparent that many changes may be made in the form, arrangement and positioning of the various elements of the combination. In consideration thereof, it should be understood that preferred embodiments of this invention disclosed herein are intended to be illustrative only and not intended to limit the scope of the invention. | A firestopping insulation construction adapted to be positioned adjacent to a head-of-wall area beneath a ceiling construction having fluted ceiling runner channels which have a trapezoidal cross-sectional profile facing downwardly. The insulation assembly includes an upper plug mated the shape of the fluted channel which is at least partially surrounded by an outer cover and further includes a lower insulation section extending over the side walls of the head-of-wall area. The upper insulation plug and the lower insulation sections are preferably made of molded high temperature insulation. The insulation assembly is engaged only frictionally to the fluted ceiling channels. | 4 |
FIELD OF THE INVENTION
This invention relates generally to artificial respiratory devices and methods, and more particularly to chemical methods for providing whole body oxygenation of a mammal whose respiratory system is partially or completely inoperative. More particularly, the present invention relates to methods and devices for treating mammals suffering from anoxia.
CROSS-REFERENCE TO RELATED APPLICATIONS AND PATENTS
This application is related to U.S. Ser. No. 428,900, filed Sept. 30, 1982, entitled "Stroke Treatment Utilizing Extravascular Circulation Of Oxygenated Synthetic Nutrients To Treat Tissue Hypoxic And Ischemic Disorders" (TJU-3-12), and is also related to U.S. Ser. No. 582,961, filed Feb. 23, 1984 of the same title (TJU-3-13). Ser. No. 582,961 (TJU-3-13) is, in turn, a division of Ser. No. 428,850 filed Sept. 30, 1982, now U.S. Pat. No. 4,445,500 (TJU-3-11), which along with Ser. No. 428,900 (TJU-3-12) are both, in turn, divisions of Ser. No. 354,346, now U.S. Pat. No. 4,445,886 (TJU-3-3) and which, in turn, is a continuation-in-part of Ser. No. 139,886 (now U.S. Pat. No. 4,378,797 (TJU-3), all of which are incorporated herein by reference as if set forth in full.
The present application is also related to the following issued United States patents, all of which are incorporated herein by reference as if set forth in full, and all of which are divisions of one or more of the other of the aforementioned Ser. Nos. 139,886 (TJU-3) and 354,346 (TJU-3-3): U.S. Pat. No. 4,445,514 (TJU-3-1); U.S. Pat. No. 4,393,863 (TJU-3-2); U.S. Pat. No. 4,450,841 (TJU-3-4); U.S. Pat. No. 4,445,887 (TJU-3-5); U.S. Pat. No. 4,446,154 (TJU-3-7); U.S. Pat. No. 4,446,155 (TJU-3-8); U.S. Pat. No. 4,451,251 (TJU-3-9); U.S. Pat. No. 4,445,888 (TJU-3-10); U.S. Pat. No. 4,445,500 (TJU-3-11).
BACKGROUND OF THE INVENTION
There are many post-traumatic and post-operative patients who develop major pulmonary complications which interfere with or preclude adequate oxygenation. The "shock lung" best characterizes this syndrome complex. Severe pneumonias, smoke inhalation, acute respiratory obstructions, pre-mature birth, and birth-related pulmonary injury also can lead to the same general problems with oxygenation. Patients with massive pulmonary embolism and hemothorax also suffer from severe hypoxemia. Combining patients in these categories, there is a substantial population of patients at high risk, but whose conditions are potentially reversible, given adequate oxygenation.
The present invention utilizes an oxygenated fluorocarbon liquid for general body oxygenation, which is applied as a circulation through the peritoneal cavity. The aforementioned incorporated patents and patent applications reference in detail various prior art publications relating to fluorocarbons and their medical uses. More recently, in the British Journal of Anaesthesia 56: 867 (1984) in an article entitled "Whole Body Oxygenation Using Intra Peritoneal Perfusion of Fluorocarbons" by Faithfull, Klein, van der Zee and Salt, results of a preliminary study undertaken to assess the feasibility of increasing the arterial oxygen tension, and decreasing the arterial carbon dioxide tension, in intact animals, by means of peritoneal perfusion with the perfluorocarbon-containing, oxygen-transporting blood substitute, 20% Fluosol-DA, were disclosed. This British Journal of Anaesthesia article is not believed to be prior art to the present application.
See also U.S. Pat. No. 4,402,984 (Moore).
SUMMARY OF THE INVENTION
The present invention provides a novel method of whole body oxygenation of the tissue of a living mammal comprising the steps of: providing an oxygenated fluorocarbon-containing liquid; injecting said oxygenated fluorocarbon liquid into the peritoneal cavity of said mammal; and withdrawing said fluorocarbon liquid from said cavity, said injecting and withdrawing being conducted at a rate sufficient to oxygenate at least a portion of the tissue of said mammal. In accordance with the preferred embodiment of the present invention, an oxygenated fluorocarbon emulsion having an aqueous component, a fluorocarbon component, and an emulsification component is utilized which is oxygenated to a pO 2 in excess of 500 mmH g prior to injection. The preferred rate of injection is above 20 milliliters per minute per kilogram of body weight of said mammal, preferably about 25 milliliters per minute per kilogram of said body weight. In the preferred embodiment, the perfusion rate is selected to increase the arterial blood gas of said mammal. Accordingly, the method of the present invention provides a novel "artificial lung" which may be used to provide sufficient oxygen to the blood to maintain life even in the presence of complete or near complete respiratory failure.
These and other objects of the invention will become apparent from the following more detailed description.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides a novel method for oxygenating the tissue of a living mammal employing an oxygenated fluorocarbon containing liquid. The preferred fluorocarbon containing liquid is the oxygenated fluorocarbon nutrient emulsion which is disclosed in my aforementioned United States patents, such as U.S. Pat. No. 4,445,886, which has been incorporated by reference as if fully set forth herein. Although this fluorocarbon containing emulsion is presently preferred, it is anticipated that certain constituents presently contained in this emulsion may be eliminated from the fluorocarbon containing liquid used in accordance with the preferred embodiment of the present invention. For example, to minimize the likelihood of bacterial growth, glucose may be eliminated from the fluorocarbon emulsion formulation. Similarly, the subject amino acids and steroids in the subject composition may be eliminated, if desired. Although not presently preferred, it is within the scope of the present invention to inject a liquid consisting essentially of the oxygenated fluorocarbon itself. In this treatment modality, it will be preferred to follow this fluorocarbon treatment with a lavage intended to wash remaining fluorocarbon from the peritoneum at the conclusion of treatment. This lavage may comprise injecting isotonic saline with or without a detergent or emulsifier, such as the pluronic disclosed in the aforementioned patent, to thereby reduce the likelihood of long term toxicity. Under most circumstances, it will be preferred that either or both of the subject perfusate and the subsequent lavage contain an antibiotic, such as bacitracin, to minimize the incidence of peritoneal infection.
In order to ensure that substantial oxygen transfer will occur, it is presently preferred to oxygenate the subject fluorocarbon containing liquid to a pO 2 in excess of 500 mmHg prior to injection. As reported in the aforementioned patents, these oxygen tensions are easily obtainable with the subject oxygenated fluorocarbon emulsion.
The present invention was reduced to practice, and its utility demonstrated, through performance of the following examples:
Experiments were begun using a male 11 pound orange tabby cat which was anesthetized using a 35 milligram per kilogram intra-muscular injection of ketamine. Thirty minutes later, 20 milligrams of flexedil, a respiratory paralytic was administered at 20 milligrams intravenously, and the animal then placed on a respirator. After 20 minutes, its arterial blood was determined to have a pH of 7.430, a pCO 2 of 25.5, and a pO 2 of 103. The aforementioned oxygenated nutrient emulsion (using the fluorocarbon FC-80) was placed in a Harvey pediatric oxygenator (volume 1230 cc) and maintained at about 40° C. Large (1/2 to 3/4 inch) cannulas were placed through two flank incisions into the peritoneum. A Randoff pump was initially used to inject the oxygenated fluorocarbon nutrient emulsion into the peritoneum through one of the cannulas, the second cannula being routed back to the oxygenator for recirculation and reoxygenation of the subject fluorocarbon emulsion. After 10 minutes of administration of a 90% N 2 O--10% O 2 respiratory gas mixture, the pH of the arterial blood was determined to be 7.374, the pCO 2 to be 28.2, and the pO 2 to be 48. Perfusion of the peritoneal space was established at a flow rate greater than 200 milliliters per minute. Problems were encountered, however, with the patency of the return line. Apparently, fatty tissue was being drawn into the return line, a condition which persisted until the catheters were manipulated into the space below omentum, which resolved the problem. Before the collection of meaningful data could be obtained, however, an inadvertent disconnection of the respirator resulted in the expiration of the test animal. Accordingly, a second series of tests were performed using a male, white and grey, 91/2 pound cat. At 2:05 p.m. 150 milligrams of ketamine and 0.18 milligrams of atropine were administered intra-muscularly. At 2:15 p.m. a 70/30 mixture of N 2 O/O 2 was begun through a respirator. At 2:30 p.m. 20 milligrams of flexedil was administered. The arterial blood gas at 2:35 p.m. registered a pCO 2 of 43.2, a pO 2 313; the pH was 7.283. The relatively higher small pO 2 of this arterial blood gas is considered within the normal range given the possibility of some hyperventilation and the administration of a respiratory gas containing 30% oxygen. At 2:35 p.m. the respirator was adjusted to increase the volume to 45 from 35. At 2:50 p.m. the arterial blood gas was 36 pCO 2 , 306 pO 2 , at a pH of 7.318. At 2:55 p.m. a 90/10 N 2 O/O 2 mixture was substituted as the respiration gas. At 3:05 p.m. the aforementioned fluorocarbon emulsion from the Harvey pediatric oxygenator was determined to have an oxygen tension of 565, a carbon dioxide tension of 25, and a pH of 7.951. at 3:10 p.m. the arterial blood gas of the subject animal had an oxygen tension of 48, a carbon dioxide tension of 33.4 and a pH of 7.335. At 3:15 p.m. the arterial blood gas of that animal exhibited a pO 2 tension of 28 mmHg, a carbon dioxide tension of 38.4 mmHg and a pH of 7.354. At 3.24 p.m. the carbon dioxide tension was 43.5, the oxygen tension 36 and the pH 7.311. At 3:36 p.m. the carbon dioxide tension was 37.8, the oxygen tension 36, and the pH 7.292. At 3:58 p.m. the pH was 7.260, the carbon dioxide tension was 42.4, and the oxygen tension was 34. At 4:05 p.m. the oxygen tension of the injected and withdrawn fluorocarbons was determined. The fluorocarbon injected was determined to have an oxygen tension of 594 and a pH of 6.815; the fluorocarbon withdrawn from the peritoneum was found to have a pO 2 of 511 and a pH of 6.865. The carbon dioxide tension in the withdrawn fluid was determined to be 26.7, but was not determined for the input fluorocarbon at this time. At 4:15 p.m. the arterial blood gas was determined to have a pH of 7.212, a carbon dioxide tension of 40.7 and a pO 2 of 42. At 4:20 p.m. the fluorocarbon was determined to have pH of 7.612. Unfortunately, the pO 2 electrode used to determine oxygen tensions in this test was apparently poisoned by the fluorocarbon, and therefore provided doubtful accuracy. It is believed that it was recalibrated, and at 4:20 p.m. the arterial blood gas pH was found to be 7.170, the pO 2 tension to be 46, and the carbon dioxide tension to be 36.3. Return flow, i.e., withdrawal of the fluorocarbon containing liquid from the peritoneum, was improved in this test by routing the exit cannula to a ballast receptacle at atmospheric pressure which was then used as an intermediate reservoir to supply the oxygenator input. As seen from the above, a systemic arterial pO 2 of approximately 30 mmHg (i.e., 28-36 mmHg) was achieved by drastic hypoventilation. When oxygenated fluorocarbon was perfused through the cat peritoneum at rates of about 200 to 250 milliliters per minute, this severe hypoxia was alleviated, as indicated by increased systemic pO 2 of about 46 mmHg.
Accordingly, the method of the present invention has been demonstrated as being useful in treating systemic anoxia under conditions where the subject mammal's respiratory system is not capable of providing normal arterial pO 2 tensions. | A novel method of oxygenating the tissue of a living mammal is disclosed comprising the steps of providing an oxygenated fluorocarbon-containing liquid; injecting that oxygenated liquid into the peritoneal cavity of said mammal; and withdrawing said fluorocarbon liquid from said cavity, said injecting and withdrawing be conducted at a rate sufficient to oxygenate said tissue. Accordingly, a novel "artificial lung" is disclosed which is useful to selectively oxygenate the body of a mammal, as reflected by increased arterial blood gas (pO 2 ) in said mammal. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a method of distributing computer software and, more particularly to a method of distributing computer software which enables a software distributor to provide multiple data files on a distribution media, to distribute identical copies of the media to a plurality of potential software users, and to selectively provide different software users with access to different sets of data files contained on the media.
Computer data files, e.g. word processing software, engineering application software, mailing lists, etc., are generally distributed by software publishers to software users on media which contain data files for only that software which the user has purchased. However in the case of institutional software distribution such as distribution to universities or large commercial organizations, publishers often bundle together a large number of different software programs on a single media volume such as a large data storage tape. Identical copies of this large capacity volume are then distributed to each of the publisher's institutional clients. Updated copies of the large capacity volume are generally distributed to clients at periodic intervals, e.g. monthly. A significant cost savings is achieved by the publisher through such large volume distribution of software due to efficiencies in both media costs and copying costs as compared to costs of preparing and distributing individual software programs on separate, low capacity media.
However, a drawback to this method of distributing institutional software on identical large volumes has been that not all institutional customers are interested in the same software. Typically each customer is interested in only some small portion of the software which is available on each large volume. Yet the customer, in order to gain access to the software which is desired, must pay for the entire volume. Due to the practical difficulty in requiring a customer to pay for software which the customer does not desire, the unit price for software which is distributed on such large identical volumes must necessarily be much lower than the unit price of software which is distributed as individual programs on small capacity media. An associated problem is that once a large volume of media is released to a customer, all of the software programs contained on the volume may be subject to unauthorized copying.
The copying costs associated with providing large "customized" software volumes to each institutional customer which contains only the software which each customer has actually ordered make this method of distribution expensive.
The present invention seeks to combine the media cost and copying cost efficiencies associated with providing numerous data files on a single large capacity media volume with the pricing efficiencies associated with providing individual software programs on separate low capacity media volumes. The present invention is particularly adapted to exploit the high capacity and relatively low copy cost associated with publishing software on ROM disks.
SUMMARY OF THE INVENTION
The present invention is directed to a software distribution method which achieves a number of desireable results for a software distributor.
All of the software which is to be distributed to a particular set of customers may be distributed on identical large capacity media volumes rather than media volumes which are unique to each customer. Thus the distributor's production costs are significantly reduced as compared to customer specific distribution methods.
The distributors's customers are provided with specially adapted reading devices. Data files on the media are encrypted and only those software users which have been provided with the specially adapted reading devices are capable of reading the data files in a usable form. The encryption "keys" needed to decrypt the data files are provided on the media and the specially adapted reading devices but are not directly accessible by software users. Thus, the risk of authorized software users making unauthorized use of the encryption keys or divulging the encryption keys to unauthorized users is obviated.
By use of a technique employing two encryption keys, a unique key for each new media release which is provided on the media itself and a "generic" key which is provided on each media reading device, each new edition of the media may be encrypted with a different key and yet still be decryptable by use of the specially adapted reading devices without modification of the firmware of the reading devices.
A technique of providing a customer a "group access map" which is compared by a security program installed in the reading device to a "region access map" on the media allows the software distributor to precisely designate different file group access for different customers.
The invention employs a password based access verification procedure which utilizes identifiers specific to a particular media release, a particular reading device and a particular set of data files. This verification procedure limits a customer's access to only those data files of a particular media release for which he has been granted access authorization by the distributor. The particular password provided to one customer is not usable by other customers due to the system's use of different reading device identifiers. Similarly the password used by a customer to gain access to files on one media release is not usable to gain access to files on a subsequent release due to the use of different media identifiers on each new release.
The present invention may comprise a method of distributing a plurality of data files to a plurality of recipients including the steps of: placing encrypted copies of the data files to be distributed on a plurality of identical media and providing the recipients with media reading devices having data file decryption capability; logically arranging the data files into data file groups; in response to a recipient's request for access to selected file groups providing the recipient with a group access map indicative of the file groups to which access is requested; in further response to a recipient's request for access to selected file groups providing the recipient with a password to be used for access verification; completing an access verification operation using the group-access map and the password and data indicative of the media being read and data indicative of the reading device being used; providing access to the data files in the file groups to which access is requested by use of the group access map; and decrypting the accessed data files.
The invention may also comprise a method of distributing a plurality of data files to a plurality of recipients including the steps of: creating a plurality of identical media which each contain copies of the plurality of data files encrypted with a first encryption key and which each contain a copy of the first encryption key encrypted with a second encryption key; providing each of the recipients with a media reading device having a machine readable copy of the second encryption key stored therein; initiating reading of one of the media on one of the media reading devices; reading the stored copy of the second encryption key; using the read copy of the second encryption key to decrypt the encrypted copy of the first encryption key which is provided on the media; and using the decrypted first encryption key to decrypt the encrypted data files on the media.
The invention may also comprise a method of distributing a plurality of data files to a plurality of recipients including the steps of: creating a set of identical media which contain copies of the plurality of data files, a media identifier, and a security program initiator; providing the recipients with secured media reading devices which each contain a common security program and which each contain a unique reading device identifier; initiating reading of one of the media on one of the media reading devices; initiating the security program in response to reading the security program initiator; inputting to the reading device a group access map indicative of particular files which are to be accessed; inputting to the reading device a password which is correlated to the unique reading device identifier of the reading device being used and to the media identifier of the media being read and to the input group access map; utilizing the security program to access the unique reading device identifier of the reading devices and the media identifier of the media being read; performing a verification operation to establish that a predetermined correlation exists among the password, reading device identifier, media identifier, and group access map; and providing access to the selected data files indicated by the group access map in response to establishing the correlation.
The invention may also comprise a method of providing access to selected sets of data files which are provided on a digital data storage media including the steps of: logically assigning each data file to a file group based upon predetermined criteria and assigning a unique file group number to each file group; logically dividing the area on the disk on which data files are stored into a plurality of contiguous physical regions wherein each data file is contained within a single region and wherein no region contains data files of more than one file group; providing a region access map indicating the group number of the files in each region and indicating the disk location of each region and providing the region access map list on the media; creating a group access map indicating the file group numbers of the file groups to which access is desired; comparing the group access map to the region access map to determine the region locations of the data files in each of the file groups to which access is desired; and providing access to each of these determined regions.
The invention may also comprise a method of distributing a plurality of data files to a plurality of recipients including the steps of: creating a plurality of identical media which each contain copies of the plurality of data files encrypted with a first encryption key, a copy of the first encryption key encrypted with a second encryption key, a media identifier, and a security program initiator; logically assigning each data file to a file group based upon predetermined criteria and assigning a unique file group number to each file group; logically dividing the area on the disk on which data files are stored into a plurality of contiguous physical regions wherein each data file is contained within a single region and wherein no region contains data files of more than one file group; providing a region access map indicating the group number of the files in each region and indicating the disk location of each region and providing the region access map on the media; creating a group access map indicating the file group numbers of the file groups to which access is desired; providing each of the recipients with a media reading device having firmware including a copy of the second encryption key, a unique reading device identifier, and a security program; initiating reading of one of the media on one of the media reading devices; initiating the security program in response to reading the security program initiator; inputting to the reading device the group access map indicative of particular file groups which are to be accessed; inputting to the reading device a password which is correlated to the unique reading device identifier of the reading device being used and to the media identifier of the media being read and to the input group access map; utilizing the security program to access the unique reading device identifier of the reading devices and the media identifier of the media being read; utilizing the security program to perform a verification operation to establish that a predetermined correlation exists among the password, reading device identifier, media identifier, and group access map; utilizing the security program to compare the group access map to the region access map to determine the region locations of the data files in each of the file groups to which access is desired and providing a recipient access to each of these determined regions; utilizing the security program to read the stored copy of the second encryption key; utilizing the security program to use the read copy of the second encryption key to decrypt the encrypted copy of the first encryption key which is provided on the media; and utilizing the security program to use the decrypted first encryption key to decrypt the encrypted data files on the media regions accessed by the recipient.
BRIEF DESCRIPTION OF THE DRAWING
An illustrative and presently preferred embodiment of the invention is shown in the accompanying drawings in which:
FIG. 1 is a schematic illustration of a software distributor, software users, software distribution media, and media reading devices.
FIG. 2 is a schematic illustration of the contents of a secured software distribution media.
FIG. 3 is an illustration of typical data contained in a region access map.
FIG. 4 is an illustration of typical data contained in a default group access map.
FIG. 5 is an illustration of typical data contained in a group access map and password.
FIG. 6 is a schematic drawing of major components of a disk drive.
FIG. 7 is a block diagram illustrating the operation of a security software program.
FIG. 8 is a block diagram illustrating a group access map validation operation of a security software program.
DETAILED DESCRIPTION OF THE INVENTION
As illustrated in FIG. 1, identical copies of a secured media such as read-only, compact laser disk 10 (hereinafter ROM disk 10 or simply disk 10) are supplied to a plurality of different software users 12, 14 by a software distributor 20. Each disk 10 contains many different data files 15, 16, etc., FIG. 2. Each data file belongs to a particular file group. Each of these file groups provides a software module which a software user may desire to use. For example, one file group may contain a single word processing program; another file group may contain a structural engineering design program and an engineering drawing program; another file group may contain a text file telephone directory of a particular geographic region, etc.
The disks 10 are secured in a manner which enables the distributor to limit access to data files on the disk to software users having media reading devices, e.g. 100/200, which have been provided with special security identifier data and software by the distributor. The distributor is able to limit the access of software users having such special reading devices to only those file groups to which a particular software user has been granted access authority by the distributor.
Each ROM disk 10 has a continuous spiral-shaped path upon which data is stored. FIG. 2 is a schematic illustration showing different areas of the disk on which information is stored. The first area on which information is stored corresponds to the area which the drive 100 would read first at system start-up. This area is a conventional disk system area 40 and contains data which enables the disk reader to properly interface with the disk being read. Such start-up regions on ROM disks are conventional and well-known in the art. The disk system area 40 is written in clear text, i.e. the data is not encrypted and may be read by any ROM disk reading device.
A security disk header 42 is provided in the area of the disk immediately after the disk system area 40. The security disk header 42 is also written in clear text and provides data which alerts the reading device to the fact that the disk being read is a secured disk.
The next area immediately after the security disk header 42 is the security system area 44 which contains various data used in implementing disk security.
The first region in security system area 44 contains a first encryption key 50. The security system area 44 also contains a region access map 52, a default group access map 54, and a media edition identifier 56, each of which is described in further detail below.
The next disk area immediately after the security system area 44 is the user data file area 46 which contains a file directory and a series of data files 15, 16, etc., which are numbered sequentially in the drawing for purposes of explanation as file no. "0" through file no. "n". Each file group which a user may desire to obtain access to includes one or more of these data files. However the data files which belong to any particular file group are not necessarily contiguous.
One technique which is used according to the present invention for securing media 10 is "data encryption". Data encryption refers to the scrambling of a set of data according to a set procedure such that the scrambled data is unusable by unauthorized parties but such that the data may be unscrambled by parties having knowledge of the scrambling procedure. One method of encrypting data known in the industry as the "Data Encryption Standard" or "DES" utilizes a device such as a microprocessor which employs a plurality of algorithms which operate on an input data string and which output a scrambled string of data of identical size to that which was input. The algorithms which operate on the input data may be varied in accordance with a predetermined procedure which is determined by a separate set of data referred to as an "encryption key" or simply a "key". The DES device may be operated in a decryption mode to perform an unscrambling operation on decrypted data which is the inverse of the encryption operation. Thus, through use of a DES chip operating in an encryption mode which is supplied with a predetermined encryption key, a set of data files may be encrypted in a manner which renders them unusable by unauthorized personnel. These encrypted data files may subsequently be returned to their original form through use of an identical encryption chip operating in a decryption mode which has been supplied with the same encryption key which was used to encrypt the files. The media security system of the present invention employs data encryption according to a novel method.
The first encryption key 50 which is stored in the first region of the security area is encrypted using a predetermined encryption standard such as that provided by using predetermined encryption software, or, in the preferred embodiment, by using an encryption chip which may be a Data Encryption Standard (DES) chip such as a Z8068 Data Cyphering Processor manufactured by Zilog, Inc., 210 Hacienda Avenue, Campbell, Calif. 95008-6609. The encryption of the first encryption key is performed using a second encryption key with the encryption device. The remainder of the system area 44 and the user data file area 46 is encrypted using the same encryption device and using the first encryption key (in its unencrypted form) with the encryption chip.
The region access map 52 is a security directory, FIG. 3, which logically divides the user data file area 46 of the disk into a series of contiguous physical regions for the purpose of identifying where data files assigned to various file groups are located. Each defined region in the user data file area 46 contains one or more contiguous files of a single file group but not necessarily all of the files of that particular file group. In other words, each region is assigned to a group. Multiple regions can be assigned to a single group, but a single region can only be assigned to one group. The region access map comprises a listing 62 of the starting address of each region and a corresponding list 64 of the group to which each region is assigned. Each region terminates at the beginning of the next succeeding region. FIG. 2 schematically illustrates how the user data file area is divided into contiguous regions which are numbered "0" through "m" for purposes of explanation.
FIG. 4 illustrates the default group access map 54 which simply comprises a string of "p" binary digits. The first digit in the string, indicated by reference numeral 70, represents the security status of the first file group, the second binary digit 71 represents the security status of the second file group, the pth digit in the string 75 represents the security status of the pth file group on the disk. In one preferred embodiment, a security status of unlocked is represented with a "0", and the security status of locked is represented with a "1". The default group access map 54 is used by security software 128 in association with the region access map 52 to allow or prevent access to the various file groups on the disk, as further explained below. The default group access map designates a "default set" of file groups to which a user is provided access without entering a password. A user may obtain access to additional file groups by inputting a new group access map 55 and a corresponding password 59 supplied by the software distributor. The new group access map 55 which is input by the customer is identical in form to the default group access map 54 but designates different file group access authority. In one embodiment of the invention the new group access map 54 and the corresponding password 59 are provided to the software user by the distributor as a single codeword 55/59 as illustrated in FIG. 5.
As previously mentioned, each user is provided with a reading device which may comprise a disk drive 100 and a host computer 200. The reading device 100/200 is configured by the distributor to implement the disk security function when a user attempts to read a secured disk 10 and otherwise operates in the same manner as a conventional disk reading device. In one preferred embodiment, the various security features of the reading device are all provided on the disk drive 100, as opposed to the host computer 200. Various components of the disk drive 100 are illustrated in FIG. 6. The disk drive may comprise a conventional drive electromechanical assembly 110. The drive is also provided with conventional drive controller hardware 112 and drive controller firmware 114. In addition to the conventional controller hardware, the drive is provided with a decryption chip 120 which in one preferred embodiment is a Data Encryption Standard (DES) chip such as a Z8068 Data Cyphering Processor manufactured by Zilog, Inc., 210 Hacienda Avenue, Campbell, Calif. 95008-6609. The decryption chip 120 may comprise an identical chip to that which is used to encrypt the first encryption key 50 and user data files 15, 16 which are provided on the ROM disk 10. However, the chip on the drive controller is used only in the decryption mode of operation.
The drive controller firmware 114, in addition to conventional firmware, comprises a second encryption key 124, a unique drive identifier 126, and a security software program 128.
The method by which a software user obtains access to a data file group will now be described at the software user level.
The software user 12 is provided with a ROM disk 10 and a disk drive 100 which has been configured by the software distributor 20 as described above. The disk drive in addition to novel security features may contain conventional ROM disk drive and magnetic disk drive features such as those provided on Models 9127A and 9135C magnetic disk drives manufactured and sold by Hewlett-Packard Company. The disk drive 100 is operably attached to the user's computer 200 which may comprise a conventional minicomputer or microcomputer such as a Series 300 minicomputer manufactured and sold by Hewlett-Packard Company.
The software user 12 is also provided by the software distributor 20 with a list of data file groups to which he may obtain access by inputting the proper code number. The software user selects one or more file groups from this list and then contact the software distributor 20 and informs the distributor of his selection. The distributor has in his possession, such as in a computer storage device 300, a list indicating the unique drive identifier for the drive 100, 102, etc. which is assigned to each software user 12, 14, etc. Based upon the unique drive identifier assigned to the drive of the software user 12 requesting access, and based upon the file groups which the software user 12 desires to access, and based upon the media edition identifier of the ROM disk 10 which the software user 12 has in his possession, the distributor determines a unique code word 55/59, FIG. 5, which he furnishes to the software user 12. The software user 12 then places disk 10 in the disk drive and initiates operation of the disk drive. He next inputs the code word 55/59 provided to him by the distributor when prompted by his host computer 200. If the code word provided to him by the distributor 20 corresponds correctly to the disk drive 100 and to the edition of the media 10 which the software user 12 is reading, security software on the disk drive 100 provides the user access to the selected file groups and decrypts the data in each of the selected file groups before transmitting it to the host computer 200.
The various substantive tasks which the security software program 128 of one preferred embodiment performs will now be described with reference to FIG. 7. The security software program 128 is initiated by other drive controller firmware 114 in response to the drive's reading of the security disk header 14 of disk 10. Next, the security software program reads the second encryption key 124 from the drive firmware. The security software program next provides the second encryption key to the decryption chip 120. Next, the security software program reads the encrypted first encryption key 50 from the drive firmware and instructs the decryption chip 120 to decrypt the first encryption key.
The security software program provides the decrypted first encryption key to the decryption chip 120 and instructs the decryption chip 120 to decrypt the media edition identifier from the security system area. Next, the security software program reads and stores the decrypted media edition identifier 56.
Next, the security software program reads and stores the unique drive identifier 126 from the drive firmware.
Next, the host computer 200 prompts the user to input the code word provided to him by the software distributor 20. The code word which is input comprises two parts, a group access map 55 and a password 59, which have different functions within the security program as described in further detail below.
Next, the security software program reads and stores the input group access map and password provided from the host computer 200.
Next, the security software program performs a validation operation using the media edition identifier 56, the unique drive identifier 126 and the group access map and the password provided by the user. If the validation operation fails, the user is provided access to only those user data files indicated by the default group access map. If the validation operation passes, the security program provides the encryption chip with the first encryption key 50 and instructs it to decrypt the region access map in the security area of disk 10.
Next the security program compares the input group access map to the decrypted region access map and unlocks (provides access to) those regions on the disk which are authorized by the group access map.
Finally the security program instructs the encryption chip 120, using the first encryption key 50 to decrypt any file which the user seeks to access in the unlocked regions of the disk 10. The data provided to the host computer 200 is clear text.
The validation operation performed by the security software program 128 will now be described in further detail with reference to FIG. 8. First, the security software provides a copy of the unique drive identifier 126 to the encryption chip 120 which uses it as a key. Next, the security software instructs the chip to decrypt the media edition identifier 56. Next, the security software instructs the chip 120 to decrypt the group access map portion of the code word which was input by the software user. Next, the security software segments the decrypted group access map into a series of numbers of a predetermined digit length numbers and then adds the individual numbers provided by these segments together. To that sum the security program adds the number represented by the decrypted media edition identifier to obtain a final sum. Next, this final sum or "check sum" is compared to the password 59 which is also represented as a number. If the check sum is identical to the password, then the validation operation passes; if not, the validation operation fails.
It will be appreciated by those having skill in the art that the same method described in FIG. 8 for performing a validation operation may also be performed, except for the last step, by the distributor 20 in order to initially compute the password which must be provided to the software user.
While an illustrative and presently preferred embodiment of the invention has been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art. | A method of distributing a plurality of data files to a plurality of recipients including the steps of: placing encrypted copies of the data files to be distributed on a plurality of identical media and providing the recipients with media reading devices having data file decryption capability; logically arranging the data files into data file groups; in response to a recipient's request for access to selected file groups providing the recipient with a group access map indicative of the file groups to which access is requested; in further response to a recipient's request for access to selected file groups providing the recipient with a password to be used for access verification; completing an access verification operation using the group access map and the password and data indicative of the media being read and data indicative of the reading device being used; providing access to the data files in the file groups to which access is requested by use of the group access map; and decrypting the accessed data files. | 8 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a continuation of, and claims priority to U.S. patent application Ser. No. 10/919,679 filed 17 Aug. 2004, now U.S. Pat. No. 7,689,394 which claims priority to and incorporates by reference herein in its entirety, U.S. Provisional Patent Application Ser. No. 60/497,782, filed 26 Aug. 2003.
BACKGROUND
Industrial automation has increased in scope and refinement with time. In general, industrial automation has focused on continuous processes comprising a plurality of interacting machines. Heretofore, automation has not fully developed using automation for process improvement relating to production and/or reliability related to discrete machines in certain applications.
United States Patent Application No. 20030120472 (Lind), which is incorporated by reference herein in its entirety, allegedly cites a “process for simulating one or more components for a user is disclosed. The process may include creating an engineering model of a component, receiving selection data for configuring the component from a user, and creating a web-based model of the component based on the selection data and the engineering model. Further, the process may include performing a simulation of the web-based model in a simulation environment and providing, to the user, feedback data reflecting characteristics of the web-based model during the simulation.” See Abstract.
United States Patent Application No. 20020059320 (Tamara), which is incorporated by reference herein in its entirety, allegedly cites a “plurality of work machines is connected by first communication device such that reciprocal communications are possible. One or a plurality of main work machines out of the plurality of work machines are connected to a server by second communication device such that reciprocal communications are possible. Each work machine is provided with work machine information detection device for detecting work machine information. The server is provided with a database which stores data for managing the work machines, and management information production device for producing management information based on the work machine information and on data stored in the database. In conjunction with the progress of work by the plurality of work machines, work machine information is detected by the work machine information detection device provided in the work machines, and that detected work machine information is transmitted to the main work machine via the first communication device. The main work machine transmits the transmitted work machine information to the server via the second communication device. The server produces management information, based on the transmitted work machine information and on data stored in the database, and transmits that management information so produced to the main work machine via the second communication device. The main work machine manages the work machines based on the management information so transmitted.” See Abstract.
SUMMARY
Certain exemplary embodiments can comprise obtaining and analyzing data from at least one discrete machine, automatically determining relationships related to the data, taking corrective action to improve machine operation and/or maintenance, automatically and heuristically predicting a failure associated with the machine and/or recommending preventative maintenance in advance of the failure, and/or automating and analyzing mining shovels, etc.
Certain exemplary embodiments comprise a method comprising at a remote server, receiving representative data obtained from a set of sensors associated with a machine, said representative data transmitted responsive to a transmission rate selected by a wirelessly receiving user; and storing said received representative data in a memory device.
Certain exemplary embodiments comprise a method comprising at an information device, receiving representative data from a memory device, said representative data generated by a set of sensors associated with a machine, said representative data transmitted responsive to a transmission rate selected by a wirelessly receiving user; and rendering at least one report responsive to said representative data.
Certain exemplary embodiments comprise receiving a plurality of values for a plurality of machine variables associated with one or more machine components; analyzing at least two variables from the plurality of machine variables, to determine a performance of the one or more machine components; and rendering a report that indicates the determined performance of the machine components
BRIEF DESCRIPTION OF THE DRAWINGS
A wide variety of potential embodiments will be more readily understood through the following detailed description, with reference to the accompanying drawings in which:
FIG. 1 is a block diagram of an exemplary embodiment of a machine data management system 1000 ;
FIG. 2 is a flow diagram of an exemplary embodiment of a machine data management method 2000 ;
FIG. 3 is a flow diagram of an exemplary embodiment of a machine data management method 3000 ;
FIG. 4 is a block diagram of an exemplary embodiment of an information device 4000 ;
FIGS. 5 a , 5 b , and 5 c are an exemplary embodiment of a partial log file layout for data associated with a mining shovel;
FIG. 6 is an exemplary user interface showing a graphical trend chart of electrical data for a crowd motor of a mining shovel;
FIG. 7 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data of a crowd motor of a mining shovel;
FIG. 8 is an exemplary user interface showing a relationship between speed and torque of a crowd motor of a mining shovel;
FIG. 9 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel crowd;
FIG. 10 is an exemplary user interface showing information related to driver operation of a mining shovel;
FIG. 11 is an exemplary user interface showing a graphical trend chart of electrical data for a hoist motor of a mining shovel;
FIG. 12 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data for a hoist motor of a mining shovel;
FIG. 13 is an exemplary user interface showing a relationship between speed and torque of a hoist motor of a mining shovel;
FIG. 14 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel hoist;
FIG. 15 is an exemplary user interface showing a graphical trend chart of electrical data related to a mining shovel;
FIG. 16 is an exemplary user interface showing information related to mining shovel operations;
FIG. 17 is an exemplary user interface showing position information related to a mining shovel;
FIG. 18 is an exemplary user interface showing a graphical rendering of gauges displaying pressures of mining shovel components;
FIG. 19 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures of mining shovel components;
FIG. 20 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data of hoist, crowd, and swing motors of a mining shovel;
FIG. 21 is an exemplary user interface showing a graphical trend chart of motion data related to a mining shovel;
FIG. 22 is an exemplary user interface showing a graphical trend chart of production data related to a mining shovel;
FIG. 23 is an exemplary user interface showing a graphical rendering of gauges displaying production data of a mining shovel;
FIG. 24 is an exemplary user interface providing operating statuses of mining shovel components;
FIG. 25 is an exemplary user interface showing a graphical trend chart of electrical data for a swing motor of a mining shovel;
FIG. 26 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data for a swing motor of a mining shovel;
FIG. 27 is an exemplary user interface showing a relationship between speed and torque of a swing motor of a mining shovel; and
FIG. 28 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel swing.
DEFINITIONS
When the following terms are used herein, the accompanying definitions apply:
Active X—a set of technologies developed by Microsoft Corp. of Redmond, Wash. Active X technologies are adapted to allow software components to interact with one another in a networked environment, such as the Internet. Active X controls can be automatically downloaded and executed by a Web browser. activity—performance of a function. analogous—logically representative of and/or similar to. analysis—evaluation. automatic—performed via an information device in a manner essentially independent of influence or control by a user. communicate—to exchange information.
communicative coupling—linking in a manner that facilitates communications.
component—a part. condition—existing circumstance. connection—a physical and/or logical link between two or more points in a system. For example, a wire, an optical fiber, a wireless link, and/or a virtual circuit, etc. correlating—mathematically determining relationships between two or more non-time variables. For example, correlating can comprise a gamma association calculation, Pearson association calculation, tests of significance, linear regression, multiple linear regression, polynomial regression, non-linear regression, partial correlation, semi-partial correlation multicollinearity, suppression, trend analysis, curvilinear regression, exponential regression, cross-validation, logistic regression, canonical analysis, factor analysis, and/or analysis of variance techniques, etc. cycle time—a time period associated with loading a haulage machine with an electric mining shovel. data—numbers, characters, symbols etc., that have no “knowledge level” meaning. Rules for composing data are “syntax” rules. Data handling can be automated. database—one or more structured sets of persistent data, usually associated with software to update and query the data. A simple database might be a single file containing many records, each of which is structured using the same set of fields. A database can comprise a map wherein various identifiers are organized according to various factors, such as identity, physical location, location on a network, function, etc. detect—sense or perceive. determine—ascertain. deviation—a variation relative to a standard, expected value, and/or expected range of values. digging—excavating and/or scooping. dispatch data—information associated with scheduling personnel and/or machinery. dispatcher—a person, group of personnel, and/or software assigned to schedule personnel and/or machinery. For example, a dispatcher can schedule haulage machines to serve a particular electric mining shovel. earthen—related to the earth. electrical—pertaining to electricity. electrical component—a device and/or system associated with a machine using, switching, and/or transporting electricity. An electrical component can be an electric motor, transformer, starter, silicon controlled rectifier, variable frequency controller, conductive wire, electrical breaker, fuse, switch, electrical receptacle, bus, and/or transmission cable, etc. electrical performance—performance related to an electrical component of a machine. For example, electrical performance can relate to a power supply, power consumption, current flow, energy consumption, electric motor functionality, speed controller, starter, motor-generator set, and/or electrical wiring, etc. electric mining shovel—an electrically-powered device adapted to hold, and/or move earthen materials. electric mining shovel component—a part of an electric mining shovel. A part of an electric mining shovel can be a stick, a mast, a cab, a track, a bucket, a pulley, a hoist, and/or a motor-generator set, etc. electric mining shovel system—a plurality of components comprising an electric mining shovel. An electric mining shovel system can comprise an electric mining shovel, electric mining shovel operator, dispatch entity, mine in which the electric mining shovel digs, and/or material haulage machine (e.g. a mine haul truck), etc. electrical—pertaining to electricity. electrical variable—a sensed reading relating to an electrical component. For example, an electrical power measurement, an electrical voltage measurement, an electrical torque measurement, an electrical motor speed measurement, an electrical rotor current measurement, and/or an electrical transformer temperature measurement, etc. environmental variable—a variable concerning a situation around a machine. For example, in the case of an electric mining shovel, an environmental variable can be a condition of material under excavation, weather condition, and/or condition of an electrical power supply line, etc. equipment scheduling information—data associated with a plan for machinery such as locating, operating, storing, and/or maintaining, etc. expected—anticipated. export—to send and/or transform data from a first format to a second format. failed component—a part no longer capable of functioning according to design. failure—a cessation of proper functioning or performance. format—an arrangement of data for storage or display. generate—produce. graphical—a pictorial and/or charted representation. heuristic rule—an empirical rule based upon experience, a simplification, and/or an educated guess that reduces and/or limits the search for solutions in domains that can be difficult and/or poorly understood. hoist—a system comprising motor adapted to at least vertically move a bucket of a mining shovel. identification—evidence of identity; something that identifies a person or thing. inactive—idle. initialization file—a file comprising information identifying a machine and the transmission of sensor data from the machine. information—data that has been organized to express concepts. It is generally possible to automate certain tasks involving the management, organization, transformation, and/or presentation of information. information device—any general purpose and/or special purpose computer, such as a personal computer, video game system (e.g., PlayStation, Nintendo Gameboy, X-Box, etc.), workstation, server, minicomputer, mainframe, supercomputer, computer terminal, laptop, wearable computer, and/or Personal Digital Assistant (PDA), mobile terminal, Bluetooth device, communicator, “smart” phone (such as a Handspring Treo-like device), messaging service (e.g., Blackberry) receiver, pager, facsimile, cellular telephone, a traditional telephone, telephonic device, a programmed microprocessor or microcontroller and/or peripheral integrated circuit elements, an ASIC or other integrated circuit, a hardware electronic logic circuit such as a discrete element circuit, and/or a programmable logic device such as a PLD, PLA, FPGA, or PAL, or the like, etc. In general any device on which resides a finite state machine capable of implementing at least a portion of a method, structure, and/or or graphical user interface described herein may be used as an information device. An information device can include well-known components such as one or more network interfaces, one or more processors, one or more memories containing instructions, and/or one or more input/output (I/O) devices, etc. Input/Output (I/O) device—the input/output (I/O) device of the information device can be any sensory-oriented input and/or output device, such as an audio, visual, haptic, olfactory, and/or taste-oriented device, including, for example, a monitor, display, projector, overhead display, keyboard, keypad, mouse, trackball, joystick, gamepad, wheel, touchpad, touch panel, pointing device, microphone, speaker, video camera, camera, scanner, printer, haptic device, vibrator, tactile simulator, and/or tactile pad, potentially including a port to which an I/O device can be attached or connected. load—an amount of mined earthen material associated with a bucket and/or truck, etc. load cycle—a time interval beginning when a mine shovel digs earthen material and ending when a bucket of the mining shovel is emptied into a haulage machine. log file—an organized record of information and/or events. machine performance variable—a property associated with an activity of a machine. For example, in the case of an electric mining shovel, a machine performance variable can be machine position, tons loaded per bucket, tons loaded per truck, tons loaded per time period, trucks loaded per time period, machine downtime, electrical downtime, and/or mechanical downtime, etc. Machine Search Language engine—machine readable instructions adapted to query information stored in an organized manner. For example, a machine search language engine can search information stored in a database. maintenance—an activity relating to restoring and/or preserving performance of a device and/or system. maintenance activity—an activity relating to restoring and/or preserving performance of a device and/or system. maintenance entity—a person and/or information device adapted restore and/or preserve performance associated with a device or system. management entity—a person and/or information device adapted to handle, supervise, control, direct, and/or govern activities associated with a machine. material—any substance that can be excavated and/or scooped. maximum acceptable value—a greatest amount in a predetermined range. measurement—a value of a variable, the value determined by manual and/or automatic observation. mechanical component—a device and/or system associated with a machine that is not primarily associated with using, switching, and/or transporting electricity. A mechanical component can be a bearing, cable, cable reel, gear, track pad, sprocket, chain, shaft, pump casing, gearbox, lubrication system, drum, brake, wear pad, bucket, bucket tooth, cable, and/or power transmission coupling, etc. mechanical performance—performance related to a mechanical component or system. For example, mechanical performance can relate to a bearing, gearbox, lubrication system, drum, brake, wear pad, bucket, bucket tooth, cable, power transmission coupling, and/or pump, etc. mechanical variable—a sensed reading relating to a mechanical component. For example, a bearing temperature measurement, an air pressure measurement, machine load reactions, and/or lubrication system pressure measurements, etc. memory device—any device capable of storing analog or digital information, for example, a non-volatile memory, volatile memory, Random Access Memory, RAM, Read Only Memory, ROM, flash memory, magnetic media, a hard disk, a floppy disk, a magnetic tape, an optical media, an optical disk, a compact disk, a CD, a digital versatile disk, a DVD, and/or a raid array, etc. The memory device can be coupled to a processor and can store instructions adapted to be executed by the processor according to an embodiment disclosed herein. metric—a measurement, deviation, and/or calculated value related to a measurement and/or deviation, etc. Microsoft Access format—information formatted according to a standard associated with the Microsoft Corp. of Redmond, Wash. Microsoft Excel format—information formatted according to a standard associated with the Microsoft Corp. of Redmond, Wash. mine—a site from which earthen materials can be extracted. mine dispatch entity—a person and/or information device adapted to monitor, schedule, and/or control activities and/or personnel associated with an earthen materials extraction operation. mine dispatcher—an entity performing scheduling and/or monitoring of equipment and/or personnel in an earthen materials extraction operation. mine dispatch system—a collection of mechanisms, devices, instructions, and/or personnel adapted to schedule and/or monitor equipment and/or personnel in an earthen materials extraction operation. minimum acceptable value—a smallest amount in a predetermined range. min/max pointer—a graphical rendering of a low and high operating range of a process variable associated with the electric mining shovel. motion gauge—a graphical rendering of a gauge associated with an electrical mining shovel. motion strip chart—a graphical rendering of a stream of process data displayed as a function of time. motion XV plot—a graphical rendering of a stream of process data displayed as a function of a non-time variable. non-binary—represented by more than two values. For example, a weight of 45 tons is non-binary; by contrast, a value, such as zero, representing a machine in an off state can be binary if an on state is solely represented by a different single value. non-digging activities—activities not involving excavating or scooping. For example, in the case of an electric mining shovel, non-digging can comprise bank cleanup, scraping, operator training, and/or repositioning an electrical cable, etc. non-load—not related to a load or quantity of material. non-positional—not related to a physical location. notify—to advise and/or remind. operational variable—a variable related to operating a machine. For example, an operation variable can be a technique used by an operator to accomplish a task with a first machine (e.g. a path used to lift a load in an electric mining shovel bucket), technique of an operator of a second machine used in conjunction with the first machine (e.g. how a mine haul truck spots relative to the electric mining shovel), practice of scheduling machines and/or personnel by a machine dispatch entity, number of second machines assigned in conjunction with the first machine, characteristics of second machines assigned in conjunction with the first machine (e.g. size, load capacity, dimensions, brand, and/or horsepower, etc.), production time period length, operator rest break length, scheduled production time for the machine, a cycle time, and/or a material weight, etc. operator—one observing and/or controlling a machine or device. pan—to move a rendering to follow an object or create a panoramic effect. panel—a surface containing switches and dials and meters for controlling a device. part—component. performance—an assessment. Performance can be measured by a characteristic related to an activity. position—location relative to a reference point. predetermined standard—a value and/or range established in advance. processor—a hardware, firmware, and/or software machine and/or virtual machine comprising a set of machine-readable instructions adaptable to perform a specific task. A processor acts upon information by manipulating, analyzing, modifying, converting, transmitting the information to another processor or an information device, and/or routing the information to an output device. production data—information indicative of a measure relating to an activity involving operation of a machine. For example, bucket load weight, truck load weight, last truck load weight, total weight during a defined production time period, operator reaction, and/or cycle timer associated with the electric mining shovel, etc. propelled motion—a linear and/or curvilinear movement of a machine from a first point to a second point. query—obtain information from a database responsive to a structured request. real-time—substantially contemporaneous to a current time. For example, a real-time transmission of information can be initiated and/or completed within about 120, 60, 30, 15, 10, 5, and/or 2, etc. seconds of receiving a request for the information. remote—in a distinctly different location. rendered—made perceptible to a human. For example data, commands, text, graphics, audio, video, animation, and/or hyperlinks, etc. can be rendered. Rendering can be via any visual and/or audio means, such as via a display, a monitor, electric paper, an ocular implant, a speaker, and/or a cochlear implant, etc. report—a presentation of information in a predetermined format. representative data—a plurality of measurement data associated with defined times. For example, representative data can be a plurality of readings from sensor taken over time period. reset—a control adapted to clear and/or change a threshold. save—retain data in a memory device. schedule—plan for performing work. schematic model—a logical rendering representative of a device and/or system. search—a thorough examination or investigation. search control—one or more sets of machine readable instructions adapted to query a database in a predetermined manner responsive to a user selection. select—choose. sensor—a device adapted to measure a property. For example, a sensor can measure pressure, temperature, flow, mass, heat, light, sound, humidity, proximity, position, velocity, vibration, voltage, current, capacitance, resistance, inductance, and/or electro-magnetic radiation, etc. server—an information device and/or software that provides some service for other connected information devices via a network. shovel motion control variable—a sensed reading relating to motion control in a mining shovel. For example, a hoist rope length, a stick extension, and/or a swing angle, etc. source—an origin of data. For example, a source can be a sensor, wireless transceiver, memory device, information device, and/or user, etc. statistical metric—a calculated value related to a plurality of data points. Examples include an average, mean, median, mode, minimum, maximum, integral, local minimum, weighted average, standard deviation, variance, control chart range, statistical analysis of variance parameter, statistical hypothesis testing value, and/or a deviation from a standard value, etc. status—information relating to a descriptive characteristic of a device and or system. For example, a status can be on, off, and/or in fault, etc. store—save information on a memory device. subset—a portion of a plurality. time period—an interval of time. transmit—send a signal. A signal can be sent, for example, via a wire or a wireless medium. transmission rate—a rate associated with a sampling and/or transfer of data, and not a modulation frequency. Units can be, for example, bits per second, symbols per second, and/or samples per second. user—a person interfacing with an information device. user interface—any device for rendering information to a user and/or requesting information from the user. A user interface includes at least one of textual, graphical, audio, video, animation, and/or haptic elements. user selected—stated, provided, and/or determined by a user. validate—to establish the soundness of, e.g. to determine whether a communications link is operational. value—an assigned or calculated numerical quantity. variable—a property capable of assuming any of an associated set of values. velocity—speed. visualize—to make visible. visually-renderable—adapted to be rendered on a visual means such as a display, monitor, paper, and/or electric paper, etc. wireless—any means to transmit a signal that does not require the use of a wire connecting a transmitter and a receiver, such as radio waves, electromagnetic signals at any frequency, lasers, microwaves, etc., but excluding purely visual signaling, such as semaphore, smoke signals, sign language, etc. wirelessly receiving user—a user that acquires, directly or indirectly, wirelessly transmitted information. wireless transmitter—a device adapted to transfer a signal from a source to a destination without the use of wires. zoom—magnify a rendering.
DETAILED DESCRIPTION
FIG. 1 is a block diagram of an exemplary embodiment of a machine data management system 1000 . Machine data management system 1000 can comprise a machine 1100 . In certain exemplary embodiments, machine 1100 can be a mining shovel such as an electric mining shovel, blast hole drill, truck, locomotive, automobile, front end loader, bucket wheel excavator, pump, fan, compressor, and/or industrial process machine, etc. Machine 1100 can be powered by one or more diesel engines, gasoline engines, and/or electric motors, etc.
Machine 1100 can comprise a plurality of sensors 1120 , 1130 , 1140 . Any of sensors 1120 , 1130 , 1140 can measure, for example: time, pressure, temperature, flow, mass, heat, flux, light, sound, humidity, proximity, position, velocity, acceleration, vibration, voltage, current, capacitance, resistance, inductance, and/or electro-magnetic radiation, etc., and/or a change of any of those properties with respect to time, position, area, etc. Sensors 1120 , 1130 , 1140 can provide information at a data rate and/or frequency of, for example, between 0.1 and 500 readings per second, including all subranges and all values therebetween, such as for example, 100, 88, 61, 49, 23, 1, 0.5, and/or 0.1, etc. readings per second. Any of sensors 1120 , 1130 , 1140 can be communicatively coupled to an information device 1160 .
Information obtained from sensors 1120 , 1130 , 1140 related to machine 1100 can be analyzed while machine 1100 is operating. Information from 1120 , 1130 , 1140 can relate to performance of at least one of the measurable parts of the electrical system, performance of at least one of the measurable parts of the mechanical system, performance of one or more operators, and/or performance of one or more dispatch entities associated with machine 1100 , etc.
The dispatch entity can be associated with a dispatch system. The dispatch system can be an information system associated with the machine. The dispatch system can collect data from many diverse machines and formulate reports of production associated with machine 1100 , personnel and/or management entities associated with the production, a location receiving the production, and/or production movement times, etc. Certain exemplary embodiments can collect information related to machine 1100 through operator input codes.
Information device 1160 can comprise a user interface 1170 and/or a user program 1180 . User program 1180 can, for example, be adapted to obtain, store, and/or accumulate information related to machine 1100 . For example, user program 1180 can store, process, calculate, and/or analyze information provided by sensors 1120 , 1130 , 1140 as machine 1100 operates and/or functions, etc. User interface 1170 can be adapted to receive user input and/or render output to a user, such as information provided by and/or derived from sensors 1120 , 1130 , 1140 as machine 1100 operates and/or functions, etc.
Information device 1160 can be adapted to process information related to any of sensors 1120 , 1130 , 1140 . For example, information device 1160 can detect and/or anticipate a problem related to machine 1100 . Information device 1160 can be adapted to notify a user with information regarding machine 1100 .
Any of sensors 1120 , 1130 , 1140 , and/or information device 1160 can be communicatively coupled to a wireless transmitter and/or transceiver 1150 . Wireless transceiver 1150 can be adapted to communicate data related to machine 1100 to a second wireless receiver and/or transceiver 1200 . Data related to machine 1100 can comprise electrical measurements and/or variables such as voltages, currents, resistances, and/or inductances, etc.; mechanical measurements and/or variables such as torques, shaft speeds, and/or accelerations, etc.; temperature measurements and/or variables such as from a motor, bearing, and/or transformer, etc.; pressure measurements and/or variables such as air and/or lubrication pressures; production data and/or variables (e.g. weight and/or load related data) such as dipper load, truck load, last truck load, shift total weight; and/or time measurements; motion control measurements and/or variables such as, for certain movable machine components, power, torque, speed, and/or rotor currents; etc.
A network 1300 can communicatively couple wireless transceiver 1200 to devices such as an information device 1500 and/or a server 1400 . Server 1400 can be adapted to receive information transmitted from machine 1100 via wireless transceiver 1150 and wireless transceiver 1200 . Server 1400 can be communicatively coupled to a memory device 1600 . Memory device 1600 can be adapted to store information from machine 1100 . Memory device 1600 can store information, for example, in a format compatible with a database standard such as XML, Microsoft SQL, Microsoft Access, MySQL, Oracle, FileMaker, Sybase, and/or DB2, etc.
Server 1400 can comprise an input processor 1425 and a storage processor 1450 . Input processor 1425 can be adapted to receive representative data, such as data generated by sensors 1120 , 1130 , 1140 , from wireless transceiver 1200 . The representative data can be transmitted responsive to a transmission rate selected by a wirelessly receiving user. Storage processor 1450 can be adapted to store representative data generated from sensors 1120 , 1130 , 1140 on memory device 1600 .
Information device 1500 can be adapted to obtain and/or receive information from server 1400 related to machine 1100 . Information device 1500 can comprise a user interface 1560 and/or a client program 1540 . Client program 1540 can, for example, be adapted to obtain and/or accumulate information related to operating and/or maintaining machine 1100 . Client program 1540 can be adapted to notify a user via user interface 1560 with information indicative of a current or pending failure related to machine 1100 . Information device 1500 can communicate with machine 1100 via wireless transceiver 1200 and wireless transceiver 1150 . Information device 1500 can notify and/or render information for the user via user interface 1520 .
Information device 1500 can comprise an input processor 1525 and a report processor 1575 . In certain exemplary embodiments, input processor 1525 can be adapted to receive representative data, such as data generated by and/or derived from sensors 1120 , 1130 , 1140 . The representative data can be transmitted responsive to a data transmission rate selected by a wirelessly receiving user. Report processor 1575 can be adapted to render at least one report responsive to received and/or representative data, such as data obtained from, for example, memory device 1600 .
FIG. 2 is a flow diagram of an exemplary embodiment of a data management method 2000 for a machine. Data management method 2000 can be used for reporting, improving, optimizing, predicting, and/or analyzing operations related to activities such as mining, driving, and/or manufacturing, etc. At activity 2100 , data can be received at an information device associated with the machine. In certain exemplary embodiments, the information device can be local to the machine. The information device can be adapted to store, process, filter, correlate, transform, compress, analyze, report, render, and/or transfer the data to a first wireless transceiver, etc.
In certain exemplary embodiments, the information device can be remote from the machine. The information device can receive data transmitted via a first wireless transceiver associated with the machine and a second wireless transceiver remote from the machine. The information device can be adapted to receive the data indirectly via a memory device. The information device can be adapted to integrate information from a plurality of sources into a database. Integrating information can comprise associating data values from a plurality of sources to a common timeclock.
In certain exemplary embodiments the data can comprise an initialization file. The initialization file can be transmitted to and/or received by a server that can be remote from the machine. The initialization file can comprise identification information related to the machine. The initialization file can comprise, for example, a moniker associated with the machine, a type of the machine, an address of the machine, information related to the transmission rate of data originating at the machine, transmission scan interval, log directory, time of day to start a log file, and/or information identifying the order in which data is sent and/or identification information relating to sensors associated with the machine from which data originates.
In certain exemplary embodiments, data can be received from a machine dispatch entity that can comprise information related to the actions of a machine dispatcher, haulage machines associated with an excavation machine, equipment scheduling, personnel scheduling, maintenance schedules, historical production data, and/or production objectives, etc.
At activity 2200 , the data can be transmitted. The data can be transmitted via the first wireless transceiver to the second wireless transceiver. The second wireless transceiver can transmit the information via a wired and/or wireless connection to at least one wirelessly receiving information device to be stored, viewed, and/or analyzed by at least one wirelessly receiving user and/or information device. In certain exemplary embodiments, transmitted data can be routed and/or received by a remote server communicatively coupled to, for example, the second wireless transceiver via a network.
In certain exemplary embodiments, the data can comprise information relating to a status of the machine. The status of the machine can comprise, for example, properly operating, shut down, undergoing scheduled maintenance, operating but not producing a product, and/or relocating, etc. The status of the machine can be provided to and/or viewed by the user via a user interface.
At activity 2300 , a transmission rate can be received at an apparatus and/or system associated with the machine and adapted to adjust transmissions from the machine responsive to the transmission rate. The transmission rate can be received from a second information device remote from the machine and/or the wirelessly receiving user. The transmission rate can be related to a transmission rate between at least the first wireless transceiver and the second wireless transceiver, and/or a sampling rate associated with data supplied from at least one sensor to the first wireless transceiver. The user can specify a transmission rate via a rendered user interface on an information device. In certain exemplary embodiments, the transmission rate can be selected via the rendered user via, for example, a pull down menu, radio button, and/or data entry cell, etc.
At activity 2400 , a data communication can be validated. For example, the first wireless transceiver can query and/or test transmissions from the second wireless receiver in order to find, correct, and/or report errors in at least one data transmission. In certain exemplary embodiments, a user can be provided with a status related to the data communication via a user interface based rendering.
At activity 2500 , data can be Stored pursuant to receipt by an information device. The information device can store the data in a memory device. The data can be stored in a plurality of formats such as SQL, MySQL, Microsoft Access, Oracle, FileMaker, Excel, SYLK, ASCII, Sybase, XML, and/or DB2, etc.
At activity 2600 , data can be compared to a standard. The standard can be a predetermined value, limit, data point, and/or pattern of data related to the machine. Comparing data to a standard can, for example, determine a past, present, or impending mechanical failure; electrical failure; operator error; operator performance; and/or supervisor performance, etc.
At activity 2650 , a failure can be detected. The failure can be associated with a mechanical and/or electrical component of the machine. For example, the mechanical failure can relate to a bearing, wear pad, engine, gear, and/or valve, etc. The electrical failure can relate to a connecting wire, motor, motor controller, starter, motor controller, transformer, capacitor, diode, resistor, and/or integrated circuit, etc.
At activity 2700 , a user can be alerted. The user can be local to the machine and/or operating the machine. In certain exemplary embodiments, the user can be the wirelessly receiving user, the dispatch entity, a management entity, and/or a maintenance entity. The user can be automatically notified to schedule and/or perform a maintenance activity associated with the machine.
At activity 2800 , data can be queried. The data related to the machine can be parsed and or extracted from a memory device. The data can be compared to a predetermined threshold and/or pattern. The data can be summarized and/or reported subsequent to the query. Querying the data can allow the wirelessly receiving user to manipulate and/or analyze the data related to the machine. In certain exemplary embodiments the data can be queried using a Machine Search Language engine.
Certain exemplary embodiments can monitor the machine while the machine is operating. Machine analysis functions can evaluate events associated with the machine. Machine analysis functions can determine causes of events and/or conditions that precede one or more events, such as a failure. Received data can be analyzed to detect average, below average, and/or above average performance associated with the machine. The information associated with the machine can be correlated with the dispatch system. In certain exemplary embodiments, applications can be customized towards individualized needs of operational units associated with the machine, such as a mine.
Certain exemplary embodiments can be adapted to remotely visualize operations associated with the machine from a perspective approximating that of an operator of the machine. Continuous monitoring and logging can take away “right timing” constraints on making direct observations of the machine. That is, performance can be logged and reviewed at a later time.
At activity 2850 , a report can be rendered. The report can comprise a summary of the data and/or exceptions noted during an analysis of the data. The report can comprise information related to, for example, actual torques, speeds, operator control positions, dispatch data, production, energy use associated with the machine, machine position, machine motion, and/or cycle times associated with the machine, etc. The report can comprise information related to the operation of the machine. For example, wherein the machine is a mining shovel, the report can comprise information related to the mining shovel digging, operating but not digging, propelling, idling, offline, total tons produced in a predetermined time period, total haulage machines loaded in the predetermined time period, average cycle time, average tons mined, and/or average haulage machine loads transferred, etc. The report can provide operating and/or maintenance entities with information related to the machine; recommend a course of action related to the operation and/or maintenance of the machine; historical and/or predictive information; trends in data, machine production data; and/or at least one deviation from an expected condition as calculated based upon the data; etc.
In certain exemplary embodiments, the data can be rendered and/or updated via a user interface in real-time with respect to the sensing of the physical properties underlying the data, and/or the generation, collection, and/or transmission of the data from the machine. The user interface can be automatically updated responsive to updates and/or changes to the data as received from the machine. In certain exemplary embodiments data can be rendered via the user interface from a user selected subset of sensors of a plurality of sensors associated with the machine. In certain exemplary embodiments data can be rendered via the user interface from a user selected subset of data point, such as, for example, every 8 th data point, every data point having a value outside a predetermined limit, every data point corresponding to a predetermined event, etc. The user can select a time period over which historical data can be rendered via the user interface. In this manner the user can analyze historical events in order to determine trends and/or assist in improving machine operations and/or maintenance.
In certain exemplary embodiments data from the machine can be rendered via the user interface which can comprise a 2-dimensional, 3-dimensional, and/or 4-dimensional (e.g., animated, or otherwise time-coupled) schematic model of the machine. The schematic model of the machine can assist the user in visualizing certain variables and/or their effects related to the machine. The schematic model of the machine can reflect a position of the machine relative to a fixed location, geographical position, and/or relative to another machine, etc. The schematic model can comprise proportionally accurate graphics and/or quantitative and/or qualitative indicators of conditions associated with one or more machine components. For a mining shovel, for example, the plurality of machine components can comprise hoist rope length, stick extension, and/or swing angles, etc. The rendering can comprise graphical indicators of joystick positions and the status displays that an operating entity can sense while running the machine. In this way, the rendering can be adapted to show a mechanical response of the machine under a given set of conditions and/or how the operating entity judges the mechanical response. The rendering can comprise an electrical response of the machine and/or how the operating entity judges the electrical response. In certain exemplary embodiments, data rendered from the machine can comprise GPS based positioning information related to the machine. The data can comprise information related to a survey. For example, in a mining operation, mine survey information can be integrated with positioning information related to the machine.
The rendering can comprise production information related to the machine. In the case wherein the machine is an electric mining shovel, production information can comprise a bucket load, haulage machine load, last haulage machine load, shift total, and/or cycle timer value, etc. The rendering can comprise electrical information such as, for example, readings from line gauges, power gauges, line strip charts, power strip charts, and/or temperature sensors related to an electrical component such as a transformer, etc. The rendering can comprise mechanical information such as, for example, readings from temperature sensors related to a mechanical component such as a bearing, air pressure sensors, lubrication system pressure sensors, and/or vibration sensors, etc.
In certain exemplary embodiments data can be rendered via a user interface in one or more of a plurality of display formats. For example, data can be rendered on a motion strip chart, motion XY plot, and/or motion gauge, etc. Data can be rendered on a chart comprising a minimum and/or maximum pointer associated with the data. The minimum and/or maximum pointer can provide a comparison of a value of a process variable with a predetermined value thereby potentially suggesting that some form of intervention be undertaken. Certain exemplary embodiments can comprise a feature adapted to allow the minimum and/or maximum to be reset and/or changed. For example, the minimum and/or maximum can be changed as a result of experience and/or a change in design and/or operation of the machine. The minimum and/or maximum can be changed by, for example, an operating entity, management entity, and/or engineering entity, etc.
The rendering can comprise elements of graphic user interface, such as menu selections, buttons, command-keys, etc., adapted to save, print, change cursors, and/or zoom, etc. Certain exemplary embodiments can be adapted to allow the user to select a subset of sensors and/or data associated with the machine to be rendered. Certain exemplary embodiments can be adapted to allow the user to select a time range over which the data is rendered. Certain exemplary embodiments can be adapted to provide the user with an ability to load and play log files via the rendering. Rendering commands can include step forward, forward, fast forward, stop, step back, play back, and/or fast back, etc. Additional features can be provided for log positioning. Certain exemplary embodiments can comprise a drop down box adapted to accept a user selection of time intervals and/or a start time.
At activity 2900 , data can be exported. Data can be exported from a memory device. Data can be exported in a plurality of formats. For example, data formatted as a SQL database can be exported in a Microsoft Access database format, an ASCII format, and/or a Microsoft Excel spreadsheet format, etc.
FIG. 3 is a flow diagram of an exemplary embodiment of a machine data management method 3000 . At activity 3100 , data can be received at a server and/or an information device. The data can comprise a plurality of values for a plurality of machine system variables associated with one or more machine system components. The plurality of machine system variables can comprise operational variables, environmental variables, variables related to maintenance, variables related to mechanical performance of the machine, and/or variables related to electrical performance of the machine, etc. In certain exemplary embodiments, the machine can be an electric mining shovel. The plurality of machine system variables can comprise at least one operational variable. In certain exemplary embodiments, the at least one operational variable can be related to digging earthen material. In certain exemplary embodiments, the at least one operational variable can comprise non-binary values.
At activity 3200 , variables from the machine data can be correlated. For example, values for two of the plurality of machine system variables can be mathematically analyzed in order to determine a correlation between those variables. Determining a correlation between variables can, for example, provide insights into improving machine operations and/or reducing machine downtime.
At activity 3300 , a metric can be determined. The metric can be a statistical metric related to least one of the machine system variables. The metric can be, for example, a mean, average, mode, maximum, minimum, standard deviation, variance, control chart range, statistical analysis of variance parameter, statistical hypothesis testing value, and/or a deviation from a standard value, etc. Determining the metric can provide information adapted to improve machine operation, improve performance of a machine operating entity, improve performance of a machine dispatching entity, improve machine maintenance, and/or reduce machine downtime, etc.
At activity 3400 , the server and/or information device can determine a trend related to at least one of the machine system variables. The trend can be relative to time and/or another machine system variable. Determining the trend can provide information adapted to improve machine design, improve machine operation, improve performance of a machine operating entity, improve performance of a machine dispatching entity, improve machine maintenance, and/or reduce machine downtime, etc.
At activity 3500 , values for one or more variables can be compared. In certain exemplary embodiments, values for a variable can be compared to a predetermined standard. For example, a bearing vibration reading can be compared to a predetermined standard vibration amplitude, pattern, phase, velocity, acceleration, etc., the predetermined standard representing a value indicative of an impending failure. Predicting an impending bearing failure can allow proactive, predictive, and/or preventive maintenance rather than reactive maintenance. As another example, a production achieved via the machine can be compared with a predetermined minimum threshold. If the production achieved is less than the predetermined minimum, a management entity can be notified in order to initiate corrective actions. If the production achieved is above the predetermined minimum by a predetermined amount and/or percentage, the management entity can be notified to provide a reward and/or investigate the causes of the production achieved.
As yet another example, an operating temperature for an electric motor controller can be compared to a predetermined maximum. If the operating temperature exceeds the predetermined maximum, a maintenance entity can be notified that a cooling system has failed and/or is non-functional. Repairing the cooling system promptly can help prevent a failure of the electric motor controller due to overheating. As still another example, an electric mining shovel idle time while operating can be compared to a predetermined maximum threshold. If the electric mining shovel idle time exceeds the predetermined maximum threshold, a mine dispatch entity can be notified that at least one additional haulage machine should be assigned to the electric mining shovel in order to improve mine production.
As still another example, a lubrication system pressure and/or use can be compared to predetermined settings. If the lubrication system is down or not performing properly, an operational and/or maintenance entity can be notified. Tracking and/or comparing lubrication system characteristics can be useful in predicting and/or preventing failures associated with inadequate lubrication.
As a further example, machine productivity can be compared to a predetermined standard. For example, in a mining operation for predetermined production period, tons mined can be compared to a historical statistical metric associated with the machine. The machine productivity comparison can provide a management entity with information that can be adapted to improve performance related to a machine operator, a dispatch entity, a maintenance entity, and/or an operator associated with a related machine.
At activity 3600 , variables associated with the machine can be analyzed. In certain exemplary embodiments, two correlated variables associated with the machine can be analyzed. In embodiments wherein the machine is an electric mining shovel, the two correlated variables can be non-load-related and/or non-positional variables related to the electric mining shovel.
Analyzing variables associated with the machine can comprise utilizing a pattern classification and/or recognition algorithm such as a decision tree, Bayesian network, neural network, Gaussian process, independent component analysis, self-organized map, and/or support vector machine, etc. The algorithm can facilitate performing tasks such as pattern recognition, data mining, classification, and/or process modeling, etc. The algorithm can be adapted to improve performance and/or change its behavior responsive to past and/or present results encountered by the algorithm. The algorithm can be adaptively trained by presenting it examples of input and a corresponding desired output. For example, the input might be a plurality of sensor readings associated with a machine component and an experienced output a failure of a machine component. The algorithm can be trained using synthetic data and/or providing data related to the component prior to previously occurring failures. The algorithm can be applied to almost any problem that can be regarded as pattern recognition in some form. In certain exemplary embodiments, the algorithm can be implemented in software, firmware, and/or hardware, etc.
Certain exemplary embodiments can comprise analyzing a vibration related to the machine based on values from at least one vibration sensor. The values can relate, for example, to a time domain, frequency domain, phase domain, and/or relative location domain, etc. The values can be presented to the pattern recognition algorithm to find patterns associated with impending failures. The values can be normalized, for example, with respect to a frequency and/or phase of rotation associated with the machine. The values can be used to obtain dynamic information usable in detecting and/or classifying failures.
Failures associated with the machine can be preceded by a condition such as, for example, a changing tolerance, imbalance, and/or bearing wear, etc. The condition can result in a characteristic vibration signature associated with an impending failure. In certain exemplary embodiments, the characteristic vibration signature can be discernable from other random and/or definable patterns within and/or potentially within the values.
Certain exemplary embodiments can utilize frequency normalization of the values. For example, frequency variables associated with power spectral densities can be scaled to predetermined frequencies. Scaling frequency variables can provide clearer representations of certain spectral patterns.
Vibration sensor readings can be sampled and processed at constant and/or variable time intervals. Certain exemplary embodiments can demodulate the vibration sensor readings. In certain exemplary embodiments, a frequency spectrum can be computed via a Fourier transform technique. The pattern recognition algorithm can be adapted to recognize patterns in the frequency spectrum to predict an impending machine component failure.
The pattern recognition algorithm can comprise a plurality of heuristic rules, which can comprise, for example, descriptive characteristics of vibration patterns associated with a failure of the component of the machine. The heuristic rules can comprise links identifying likely causes, diagnostic procedures, and/or effects related to the failure. For example, the heuristic rules can be adapted to adjust maintenance, machine, and/or personnel schedules responsive to detecting an impending failure.
Activity 3600 can comprise, for example, predicting machine performance, predicting a failure related to the machine, predicting a failure related to a machine component, predicting a failure related to a mechanical machine component, and/or predicting a failure related to an electrical machine component.
At activity 3700 , a report can be generated. The report can comprise, for example, a machine performance variable; information related to performance of a dispatch entity, such as a mine dispatch entity; information related to performance of a machine mechanical component; information related to performance of an machine electrical component; information related to activities involving the machine, such as digging activities in the case of an electric mining shovel; information related to non-digging activities involving the machine, such as operator training; and/or information related to propelled motion of the machine; etc.
At activity 3800 , a management entity associated with the machine can be notified of information related to the machine. The management entity can be notified of certain comparisons associated with activity 3500 and/or results associated with activity 3600 . Notifying the management entity can allow for corrective action to be taken to avoid lower than desired performance. Notifying the management entity can provide the management entity with information usable to improve performance related to the machine.
At activity 3900 , a maintenance entity associated with the machine can be notified. Notifying the maintenance entity can provide for prompt repair and/or prompt scheduling of a repair associated with the machine. Information obtained via activity 3600 can provide information usable in improving preventative maintenance related to the machine.
FIG. 4 is a block diagram of an exemplary embodiment of an information device 4000 , which in certain operative embodiments can comprise, for example, information device 1160 , server 1400 , and information device 1500 of FIG. 1 . Information device 4000 can comprise any of numerous well-known components, such as for example, one or more network interfaces 4100 , one or more processors 4200 , one or more memories 4300 containing instructions 4400 , one or more input/output (I/O) devices 4500 , and/or one or more user interfaces 4600 coupled to I/O device 4500 , etc.
In certain exemplary embodiments, via one or more user interfaces 4600 , such as a graphical user interface, a user can view a rendering of information related to a machine.
FIGS. 5 a , 5 b , and 5 c are an exemplary embodiment of a partial log file layout for data associated with a mining shovel. Data comprised in the log file can be saved for analytical purposes.
FIG. 6 is an exemplary user interface showing a graphical trend chart of electrical data for a crowd motor of a mining shovel. The crowd motor is adaptable to provide motion to a bucket of the mining shovel toward, to “crowd”, material holdable by the bucket.
FIG. 7 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data of a crowd motor of a mining shovel. Data used in generating the graphical rendering can be saved for analytical purposes. The graphical rendering be rendered approximately in real-time.
FIG. 8 is an exemplary user interface showing a relationship between speed and torque of a crowd motor of a mining shovel.
FIG. 9 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel crowd. Data used in generating the graphical rendering can be saved for analytical purposes. The graphical rendering be rendered approximately in real-time.
FIG. 10 is an exemplary user interface showing information related to driver operation of a mining shovel. The graphical rendering be rendered approximately in real-time.
FIG. 11 is an exemplary user interface showing a graphical trend chart of electrical data for a hoist motor of a mining shovel.
FIG. 12 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data for a hoist motor of a mining shovel. Data used in generating the graphical rendering can be saved for analytical purposes. The graphical rendering be rendered approximately in real-time.
FIG. 13 is an exemplary user interface showing a relationship between speed and torque of a hoist motor of a mining shovel.
FIG. 14 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel hoist. Data used in generating the graphical rendering can be saved for analytical purposes. Maximum and/or minimum thresholds can be set for purposes of generating alarms and/or flagging data. The graphical rendering be rendered approximately in real-time.
FIG. 15 is an exemplary user interface showing a graphical trend chart of electrical data related to a mining shovel.
FIG. 16 is an exemplary user interface showing information related to mining shovel operations.
FIG. 17 is an exemplary user interface showing position information related to a mining shovel.
FIG. 18 is an exemplary user interface showing a graphical rendering of gauges displaying pressures of mining shovel components. Data used in generating the graphical rendering can be saved for analytical purposes. The graphical rendering be rendered approximately in real-time.
FIG. 19 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures of mining shovel components.
FIG. 20 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data of hoist, crowd, and swing motors of a mining shovel.
FIG. 21 is an exemplary user interface showing a graphical trend chart of motion data related to a mining shovel.
FIG. 22 is an exemplary user interface showing a graphical trend chart of production data related to a mining shovel.
FIG. 23 is an exemplary user interface showing a graphical rendering of gauges displaying production data of a mining shovel.
FIG. 24 is an exemplary user interface providing operating statuses of mining shovel components.
FIG. 25 is an exemplary user interface showing a graphical trend chart of electrical data for a swing motor of a mining shovel.
FIG. 26 is an exemplary user interface showing a graphical rendering of gauges displaying electrical data for a swing motor of a mining shovel.
FIG. 27 is an exemplary user interface showing a relationship between speed and torque of a swing motor of a mining shovel.
FIG. 28 is an exemplary user interface showing a graphical rendering of gauges displaying temperatures related to a mining shovel swing.
Still other embodiments will become readily apparent to those skilled in this art from reading the above-recited detailed description and drawings of certain exemplary embodiments. It should be understood that numerous variations, modifications, and additional embodiments are possible, and accordingly, all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the appended claims. For example, regardless of the content of any portion (e.g., title, field, background, summary, abstract, drawing figure, etc.) of this application, unless clearly specified to the contrary, there is no requirement for the inclusion in any claim of the application of any particular described or illustrated activity or element, any particular sequence of such activities, or any particular interrelationship of such elements. Moreover, any activity can be repeated, any activity can be performed by multiple entities, and/or any element can be duplicated. Further, any activity or element can be excluded, the sequence of activities can vary, and/or the interrelationship of elements can vary. Accordingly, the descriptions and drawings are to be regarded as illustrative in nature, and not as restrictive. Moreover, when any number or range is described herein, unless clearly stated otherwise, that number or range is approximate. When any range is described herein, unless clearly stated otherwise, that range includes all values therein and all subranges therein. Any information in any material (e.g., a United States patent, United States patent application, book, article, etc.) that has been incorporated by reference herein, is only incorporated by reference to the extent that no conflict exists between such information and the other statements and drawings set forth herein. In the event of such conflict, including a conflict that would render a claim invalid, then any such conflicting information in such incorporated by reference material is specifically not incorporated by reference herein. | Certain exemplary embodiments can comprise obtaining and analyzing data from at least one discrete machine, automatically determining relationships related to the data, taking corrective action to improve machine operation and/or maintenance, automatically and heuristically predicting a failure associated with the machine and/or recommending preventative maintenance in advance of the failure, and/or automating and analyzing mining shovels, etc. | 4 |
TECHNICAL AREA
The invention is directed to game rackets and, more particularly, to a tennis racket frame having an aerodynamic profile and variable frame thickness.
BACKGROUND OF THE INVENTION
The popularity of racket sports has continuously increased over the past 10-20 years. Concomitant with this increase in popularity are the technological advances in the sports equipment. In particular, the art of design and manufacture of racket frames has developed in an effort to improve racket performance. As an example, with respect to tennis rackets, the racket frames have evolved from the use of wood as the predominant material of choice, to the steel-shafted rackets of the early 1970s, to the graphite and ceramic composites of today.
One of the most recent trends in racket design is the use of the so-called "wide body" rackets as exemplified by U.S. Pat. No. 4,664,380. This racket type has a thickness, as measured orthogonal to the stringing plane, which is larger in the throat portion, relative to the prior art. Further, the racket frame thickness tapers continuously from the throat portion to the top of the head and also tapers continuously from the throat portion to the handle. Additional "wide body" rackets of the prior art are manufactured by Prince® Mfg. This family of rackets has a constant taper, whereby the racket frame thickness progressively becomes thicker from the handle to the top of the head. The constant taper system of the Prince® racket allows for greater stiffness in the top of the head portion.
Although the overall performance of these rackets may be improved relative to other prior art, a large segment of tennis players may find these rackets unsuitable. For example, one of the important parameters of a tennis racket is the stiffness of the racket. The stiffness of a racket is defined to be the amount of racket frame resistance to a force applied orthogonal to the stringing plane. Generally, the stiffer the racket the more vibration at impact is transmitted to the tennis player. Although this vibration can be a major cause of many arm injuries, most tennis players require some measure of stiffness, because stiffness in the racket gives the player more control and accuracy and less "trampolining" effect. However, the two examples of "wide body" rackets described above may be overly stiff for many players because of the substantial thickness of the rackets, thus increasing the possibility of injury.
Moreover, another major disadvantage of the prior art is that because of the thickness of the frames, increased air resistance may be encountered during use of the tennis racket. Although air resistance with these prior art rackets may be relatively low when the racket is swung in a direction orthogonal to the stringing plane, if the racket is swung in any other direction, air resistance increases dramatically. This is because the cross-sectional profile of the frames described above can best be described as an elongated oval. Thus, the frames have a small aerodynamic profile when viewed orthogonal to the stringing plane and a much larger aerodynamic profile when viewed parallel to the stringing plane. Further, it can be appreciated that in most tennis strokes the racket does not travel directly orthogonal to the string plane, but rather in a "low-to-high" aerodynamic profile motion, thus exposing the thickest racket profile to the air when the racket is traveling at its maximum speed. In some strokes, such as the serve, the direction of racket travel may be nearly parallel to the stringing plane, once again exposing the largest racket profile to the air.
In contrast, the present invention incorporates the advantages of "wide body" rackets without the problems of excessive racket stiffness or excessive aerodynamic drag of the prior art rackets. Specifically, a lightweight tennis racket having a frame of adequate stiffness and a circular cross section is disclosed.
SUMMARY OF THE INVENTION
In accordance with the present invention, a racket frame having improved aerodynamics and optimum stiffness characteristics is disclosed. The racket frame comprises an elongated handle portion, a left and right throat portions of arcuate shape having a substantially circular cross section, an arcuate bridge portion having substantially circular cross section, and an arcuate head portion having a substantially circular cross section of variable diameter. The left and right throat portions are attached to the handle portion and extend longitudinally and curving laterally away therefrom. The arcuate bridge portion extends transversely to the length of the handle and intersects the ends of the left and right throat portions. The head portion cooperates with the bridge portion to form a closed a curvilinear shape.
In one specific embodiment of the present invention, the head portion is comprised of a top crown section, a middle section, and a lower section. The top crown section has a circular cross section diameter larger than the circular cross section diameter of the middle section. Further, the lower section has a circular cross section diameter approximately equal to the circular cross section diameter of the top crown portion.
In another specific embodiment of the present invention, the head portion has a circular cross section diameter which is substantially constant throughout and substantially equal to the circular cross section of the throat portions.
In a further specific embodiment of the present invention, the head portion is comprised of a top crown section, a middle section, and a lower section. The top crown section has a circular cross section diameter larger than the circular cross section diameter of the middle section. Further, the middle section has a circular cross section diameter which is larger than the circular cross section diameter of the lower section. Finally, the lower section has a circular cross section diameter greater than the circular cross section diameter of the throat portions. Thus, the circular cross section diameter of the racket progressively decreases from the top crown section to the throat portions.
In an additional specific embodiment of the present invention, the head portion is comprised of a top crown section, a middle section, and a lower section. The top crown section has a circular cross section diameter less than the circular cross section diameter of the middle section. Further, the lower section has a circular cross section diameter approximately equal to the circular cross section diameter of the top crown portion. Thus, the circular cross section of the racket is smaller at the top crown section, larger in the middle section, and smaller at the lower section and throat portions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a tennis racket constructed in accordance with the present invention;
FIG. 2 is a side view of the racket of FIG. 1;
FIGS. 3, 4 and 5 are cross-sectional views of the tennis racket of FIG. 1 taken substantially along lines 3--3, 4--4 and 5--5 respectively thereof;
FIGS. 6 and 7 are side views of additional preferred embodiments of a tennis racket formed in accordance with the present invention illustrating various racket profiles; and,
FIGS. 8, 9 and 10 are fragmentary plan views of the present invention illustrating alternative preferred bridge constructions.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Although the description given below is primarily for a tennis racket frame 11, it can be appreciated that the general design concepts for the frame described herein may be for a racket frame for use in any racket sport. Referring first to FIG. 1, the tennis racket frame 11 includes a handle portion 13, throat portions 15A and 15B, a head portion 17, and a bridge 19.
The handle portion 13 is a substantially cylindrical member preferably composed of a plastic-type material or other lightweight, high-strength material. The interior of the handle preferably is hollow and is filled with a foamed plastic material which provides dampening of vibrations. Further, the handle is wrapped in a grip material 14, preferably leather, which facilitates sure grasp by the racket user.
Attached to one end of the handle 13 are curved throat portions 15A and 15B. The left throat portion 15A and the right throat portion 15B are elongated, arcuate segments that flair outwardly to tangentially intersect with the head portion 17. The throat portions are composed of resin-impregnated graphite fibers or other fibers of high strength and low weight. The segments are preferably hollow and have a cross-sectional shape which is substantially circular when taken in the plane orthogonal to the longitudinal axis of the segments. In one preferred embodiment, the throat portions 15A and 15B have a cross-sectional diameter of about 15 to 27 millimeters and ideally about 21.8 millimeters. The throat portions 15A and 15B as attached to the handle 13 extend outwardly and symmetrically from the end of the handle 13 to form a "Y" shape. Further, the throat portions and the handle 13 are oriented such that they are coplanar.
The bridge 19 is illustrated as in the form of an arcuate segment preferably composed of resin-impregnated graphite fibers or other high-strength, low weight material. The bridge 19 is preferably hollow and has a circular or substantially circular cross section. In one preferred embodiment, the circular cross section of the bridge has a diameter of about 8 to 19 millimeters and ideally of about 13.4 millimeters. The bridge 19 is positioned substantially transverse to the handle 13 and is disposed such that the ends of bridge 19 tangentially intersect with the distal ends of the right throat portion 15B and the left throat portion 15A to define a generally triangular open area 20.
It is to be understood that the bridge can be of other shapes than as illustrated in FIG. 1. For instance, the bridge might extend straight across the throat as shown in FIG. 8 (bridge 119), be "Vee"-shaped as shown in FIG. 9 (bridge 219), reversed "Vee"-shaped as shown in FIG. 10 (bridge 312), or not used at all. If utilized, preferably the bridge 119, 219 or 312 is hollow and of circular or essentially circular cross section, as is the bridge 19 shown in FIG. 1. The diameter of the bridge 119, 219 and 312 will vary to meet the needs of the racket, but likely will be of the range of the diameter of bridge 19 discussed above.
The head 17 is formed in an elongated, elliptical shape. However, the head could be formed in other shapes without departing from the spirit or scope of the present invention. Also, preferably, the head 17 is composed of resin-impregnated graphite fibers or other high-strength, low weight fiber materials. The head 17 preferably is hollow and has a circular or substantially circular cross section. Further, head 17 cooperates with the bridge 19 to form a closed elliptical shape. As more fully described below, the head 17 has a circular or substantially circular cross section which may be of variable diameters. It can be appreciated that like the racket frames of the prior art, the head, throat, bridge and handle of the present invention are all substantially coplanar.
Although in the preferred embodiment described above, the elements (with the exception of handle 13) are composed of graphite fibers, it can be appreciated that the material used to construct the above components may be varied. For example, various composites of graphite, ceramic, Kevlar®, boron, aluminum and other metals may be used to form the elements. Further, although the racket elements may be hollow, in an alternative embodiment, the hollow cores of the head 17, throat portions 15A and 15B, and the bridge 19 are filled with an expanded foam plastic material of various compositions.
The wall thickness of the various elements of the racket frame may be varied depending on the particular diameter of the element, the desired stiffness thereof, and the material from which the element is constructed. For instance, if the racket elements are constructed from graphite, preferably the wall thickness of the elements may vary from about .20 millimeters to 5.0 millimeters and ideally from about .40 millimeters to 3.0 millimeters. As a result, the racket frame may weigh from about 150 to 350 grams.
As noted above, the head 17 and the bridge 19 cooperatively define a closed and substantially elliptical shape which is termed the stringing area 21. The stringing area 21 contains strings for striking a ball. The stringing area 21 is dependent upon the size and shape of head 17 and bridge 19. The stringing area 21 is preferably from 85 square inches to 109 square inches, and perhaps even larger. In one preferred embodiment of the present invention, the stringing area 21 is approximately 97 square inches.
The strings occupying the stringing area 21 are secured to the frame by means of holes in the racket frame. The holes (not shown for clarity) extend through the racket frame and allow the strings to traverse through the frame. Such holes are formed in both the head portion 17 and bridge 19 of the racket frame of the present invention. Also, along the outer periphery of the head 17 is a shallow stringing groove 29. This groove 29 allows strings which are secured to the head 17 to lie within the groove 29 such that the strings will not be damaged if the head 17 scrapes the ground during use. As seen in FIGS. 3, 4 and 5, although the groove 29 is an indentation in an otherwise circular cross section, the overall change to the circular cross section is negligible.
Still referring to FIG. 1, the head portion 17 is further comprised of lower sections 23A and 23B, middle sections 25A and 25B, and a crown section 27. It is to be understood that the crown section 27, middle sections 25A and 25B, and lower sections 23A and 23B are not distinct elements, but rather differing sections of the head portion 17 which is of singular and unitary construction. As seen in the cross-sectional view of FIG. 2, in one preferred embodiment of the present invention, the lower sections 23A and 23B have a diameter of about 21.8 millimeters middle sections 25A and 25B have a diameter of about 18.0 millimeters, and the crown section 27 has a diameter of about 21 millimeters at the very top of the head portion 17. Although the diameters of the sections comprising the head 17 differ, it can be appreciated that the transition from the lower sections, middle sections and crown section is continuous, with the head 17 maintaining a circular cross section throughout. Further, although the diameter measurements for the preferred embodiment are given above, it can be appreciated that the diameter measurements are for the particular cross sections along the lines 3--3, 4--4 and 5--5 shown in FIG. 1 and that measurements taken in the transitional areas between these cross-sectional locations will be different.
As seen in FIG. 2, the tennis racket 11, as viewed in the plane of the stringing area 21, has a "thick-thin-thick" profile. The middle sections 25A and 25B of head 17 generally have a thinner diameter than the crown section 27, lower sections 23A and 23B and throat portions 15A and 15B. This configuration allows the racket to have sufficient stiffness in the crown and throat portions for control while reducing stiffness in the ball-striking area of the middle portions 25A and 25B. Specifically, because the middle portions 25A and 25B of the head is thinner than the throat and the crown portions, the middle sections flex more when striking a ball which reduces the level of vibration generated. In addition, the stiffness arising from the increased thickness in the throat and crown portions allow for an increase in power and control.
Applicant has determined that the stiffness of the tennis racket 11 with a stringing area 21 of about 97 square inches is approximately RA 72. Of course other stiffness may be achieved by varying the cross-sectional diameters of the various elements of the racket frame, the wall thickness of the various elements as well as the material composition of the various elements.
In an alternative preferred embodiment of the present invention shown in FIG. 6, all of the sections which comprise head 17' have substantially the same cross-sectional diameter. The components of the racket frame 11' shown in FIG. 6 that are comparable to the components of the racket frame 11 shown in FIGS. 1-5 are referred to by the same part number but with a prime (') designation. The cross-sectional diameter of these sections in this embodiment ideally are between about 15 to 25 millimeters, but can be smaller or larger than this range. Further, preferably the circular cross section of the tennis racket is constant through the head portion 17 and throat portions 15A and 15B.
In an additional preferred embodiment of the present invention illustrated in FIG. 7. The components of the racket frame 11" shown in FIG. 7 that are comparable to the components of the racket frame 11 shown in FIGS.1-5 are given the same part number but with a double prime (") designation. As shown in FIG. 7, the crown section 27" has a diameter of about 35 to 25 millimeters, the middle sections 25A" and 25B" have a diameter of about 30 to 20 millimeters and the lower sections 23A and 23B have a diameter of about 25 to 15 millimeters. Thus, it can be seen that the tennis racket shown in FIG. 7, as viewed parallel to the plane of the stringing area 21", has a thickness which constantly decreases from the crown section 27" through the middle sections 25A" and 25B", the lower sections 23A" and 23B", and the throat portions 15A" and 15B".
With all of the embodiments described above, because of the circular cross section of the portions comprising the frame, enhanced aerodynamic response is provided. A racket frame having a circular cross section provides less aerodynamic drag than rackets constructed in other cross-sectional shapes. As noted above, although some shapes may have a lower aerodynamic drag in certain racket movements and orientations, for the large variety of racket strokes, the circular cross section provides the most efficient overall aerodynamic performance.
The increased efficiency created by reducing aerodynamic drag can be significant. For example, the average tennis player swings the racket on the order of 40 miles per hour (mph), whereas the top players can generate a racket head speeds approaching 100 mph. Thus, it can be appreciated that any increase in the aerodynamic profile of a tennis racket will significantly reduce energy expenditure in a tennis stroke.
While the preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. Thus, within the scope of the appended claims, it is to be understood that the invention can be practiced otherwise than as specifically described herein. | A game racket (11) having improved aerodynamics and hitting response is disclosed. With the exception of the handle (13) the entire racket is comprised of elements all having a substantially circular cross section. The head (17) of the racket (11) is comprised of three sections. Each section may have a different cross sectional diameter. | 0 |
[0001] The present patent document is a nationalization of PCT Application Ser. No. PCT/EP2007/050118, filed Jan. 5, 2007, designating the United States, which is hereby incorporated by reference. This application also claims the benefit of DE 10 2006 004 590.4, filed Feb. 1, 2006, which is hereby incorporated by reference.
BACKGROUND
[0002] The present embodiments relate to a mammography appliance with a stand, to which an appliance rack is attached. The mammography appliance includes a compressing unit with an object table and a compressing plate.
[0003] A mammography appliance is used to perform medical examinations of the soft tissue of the human breast with X-ray radiation. The medical examinations are used for the early identification of breast cancer. The breast is clamped between the object table and the compression plate, which can be moved toward the object table. An X-ray examination is then performed with the irradiation unit embodied as an X-ray tube. An X-ray detector is integrated in the object table. During the irradiation, soft X-ray radiation in the range below 50 kV, in particular below 30 kV is used.
[0004] Mammography appliances, such as the “Mammomat 1000”, “Mammomat 3000 Nova” and “Mammomat Novation,” have a similar structural design. As a representative example, the “Mammomat Novation” has a main body embodied as a stand and an appliance arm protruding from the stand at an angle at the free end of which a radiation source is arranged. The appliance arm is implemented as a sheet-metal structure and connected in a rotationally fixed manner to a horizontal rotary axis of the mammography appliance so that the radiation source can be swiveled 360° about an isocenter. An object table is mounted on the appliance arm by a rotary joint and can be swiveled 360° about the isocenter.
[0005] The protruding angled appliance arm, to which the irradiation unit and the compression unit are attached, exerts high mechanical leverage forces, which require a complex mechanical design. The appliance arm also performs the rotary or swivel movements required for the different types of examination. For example, the mammography device is usually used for screening examinations, in which the irradiation unit is located in a 0° position. The irradiation unit and the object table are arranged opposite each other in the longitudinal direction. The mammography appliance is designed for a stereotactic examination in which the breast is irradiated from two different angles. The irradiation unit is swiveled out of the resting position by ±10° or by ±15° about the horizontal axis with a fixed object table. Tomosynthesis examinations may be performed with the mammography appliance in which the irradiation unit moves continuously over a comparatively large angular range, for example, in an angular range of ±25° about the horizontal axis with a fixed object table. It is usually possible to produce an MLO (mediolateral oblique) view. During this kind of examination, the irradiation unit again moves over a large angular range, wherein the object table follows the irradiation unit so that the object table and irradiation unit are always aligned in the same position respective to each other and at the same distance from each other. The mammography appliance permits imaging of the breast to be examined in standard views, such as craniocaudal (CC) or mediolateral oblique (MLO) views.
SUMMARY AND DESCRIPTION
[0006] The present embodiments obviate one or more of the problems or drawbacks inherent in the related art. For example, in one embodiment, a mammography device has a simple design.
[0007] In one embodiment, a mammography appliance includes an irradiation unit that is attached to a C-arm-type support arm, lying in a swivel plane perpendicular to a horizontal axis. Within the swivel plane, the irradiation unit can be swiveled in the case of, for example, a stereotactic or tomosynthesis examination.
[0008] A C-arm-type support arm is a support arm bent in a C shape. The C-arm is arranged within the swivel plane and does not extend in the direction of the horizontal axis. Compared to the conventional, bent appliance arm, lower leverage forces are exerted on the stand. The C-arm design of the support arm defines a circular path on which the irradiation unit travels during a swivel movement. The use of the C-arm-type support arm also, alternately, overrides or, at least alternately, attenuates the active leverages so that the leverages acting on the stand are low. The C-arm achieves a very stable and simultaneously very compact design. The C-arm between the irradiation unit and the object table creates a free space with no supporting elements which is now available for other functional assemblies.
[0009] To enable the irradiation unit to swivel, the support arm itself is swivel-mounted. Alternatively, or supplementarily, the support arm is telescopic and the irradiation unit is arranged on a movable telescopic arm. The support arm may be arranged in an immobile and fixed manner and the telescopic arm to be extended or retracted to facilitate the swivel movement of the irradiation unit. Since the support arm overall has a C-arm design, the telescopic arm is bent in accordance with the bend in the C-arm. On the extension of the telescopic arm, the irradiation unit is moved along a circular line.
[0010] In one embodiment, the telescopically-designed support arm and the swivel mounting of the support arm are combined. The two swivel mechanisms may be matched to each other in such a way that the telescopic swivel movement can be used, for example, to perform the swivel movement of ±10° or ±15° usually required for a stereotactic examination or that of ±25° for a tomosynthesis examination. If a more extensive rotary movement is desired for the MLO examination, the support arm overall is swiveled, together with the object table. The swivel movement of the support arm is directly coupled to the swivel movement of the object table, so that there is a rigid connection between the support arm and the object. When the telescopic arm is extended, the object table remains in its usually horizontal initial position.
[0011] In an alternative embodiment, a swivel movement of the whole support arm is provided during the stereotactic and/or tomosynthesis examination. The object table is decoupled or decouplable from the swivel movement of the support arm so that the object table remains in its normal horizontal position. The object table can be coupled to the swivel movement of the support arm for an MLO examination.
[0012] The support arm in the swivel plane is arranged directly in front of the stand, or alternatively, above or below the stand. Accordingly, the leverage forces acting on the stand are kept as low as possible. In one embodiment, the C-arm is arranged parallel to the front side of the stand directly adjacent to this front side. “Arranged . . . directly” means at the most a distance of a few centimeters. In another embodiment, the support arm is arranged on the face end of the stand when viewed in the longitudinal direction of the stand. With this face-end arrangement, the stand and the support arm are preferably arranged in alignment with each other in the longitudinal direction so that no leverage forces act on the stand. With the arrangement above the stand, the stand is attached at the base and with the arrangement below the stand it is attached to a ceiling. The base-side arrangement of the stand has a high mechanical stability, since here the weight forces of both the stand and the support arm are transmitted along the longitudinal direction into the base.
[0013] In one embodiment, the stand includes a bearing element to which the support arm is attached. In the embodiment with the support arm attached in a swivelable manner to the stand the support arm is rotatably mounted about the horizontal axis on the bearing element. In the embodiment with a face-end arrangement of the support arm on the stand, the support arm is attached to the stand by the bearing element.
[0014] The support arm is mounted on the bearing element with an end-side mounting end. The irradiation unit is arranged at the other end of the support arm. The irradiation unit and mounting point are arranged opposite each other on the two ends of the C-arm. Alternatively to this, the support arm is guided in the support element in the style of a sliding bearing so that the support arm is guided along the bearing element. A swivel movement of the support arm varies the angular distance between the mounting point (bearing element) and the irradiation unit.
[0015] In one embodiment, the compression unit is attached rotatably on the bearing element and about the horizontal axis. The support arm and compression unit are attached together on the bearing element. The compression unit is rigidly connected to the support arm. Alternatively, the compression unit is decoupled and attached rotatably on the bearing element independently of the support arm.
[0016] In one embodiment, the appliance rack includes a biopsy unit which can be moved from a parked position into a biopsy position. During a biopsy, a tissue sample is taken, usually by a needle. The parked position is arranged in a free parking space encompassed by the C-arm-type support arm. The free space created by the use of the C-arm is used for this parked position. The parking space lies within the swivel plane. Using the C-arm, even on the swiveling of the support arm or the irradiation unit, there is no risk of collision with the biopsy unit.
[0017] The biopsy unit is swivel-mounted on the compression unit. The biopsy unit is moved into the biopsy position without problems. This permits a particularly compact and simple structural design.
[0018] The free space created by the C-arm is expediently utilized in such a way that a display and/or operator panel is arranged on the stand and to be precise in such a way that the operating personnel can view or access this from the front without, for example, a component of the appliance, such as the irradiation unit or the compression unit obstructing the access to or the view of display and/or operator panel.
[0019] In order to be able to set a vertical adjustment and hence an adaptation to the height of a person to be examined, the stand may be vertically adjustable together with the appliance rack, for example, when the appliance rack is firmly connected to the stand with respect to vertical adjustability. Alternatively, the appliance rack is vertically adjustable relative to the stand, for example, when the stand itself is not vertically adjustable. The two mechanisms for height adjustment can also be combined with each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1A-1C illustrate a front view of a mammography appliance in different irradiation situations,
[0021] FIG. 2 illustrates a top view of a mammography appliance,
[0022] FIG. 3 illustrates a top view of an alternative embodiment of a mammography appliance,
[0023] FIG. 4A illustrates a side view of an appliance rack with a biopsy unit in a biopsy position,
[0024] FIG. 4B illustrates a side view of the appliance rack according to FIG. 4A , wherein the biopsy unit is arranged in a parked position,
[0025] FIG. 5A illustrates a mammography appliance with a height-adjustable stand,
[0026] FIG. 5B illustrates a mammography appliance, in which an appliance rack is vertically adjustable relative to the stand and
[0027] FIG. 5C illustrates a mammography appliance, in which the stand is attached at the ceiling side
DETAILED DESCRIPTION
[0028] FIG. 1A , 1 B, 1 C show a front view of a mammography appliance in the typical irradiation and examination situations for a mammography. FIG. 1A shows the mammography appliance in a 0° position for a screening examination (CC image: craniocaudal). In this 0° position, an irradiation unit 2 is located in a 12-o'clock position and is oriented parallel to a vertical longitudinal direction 4 . FIG. 1B shows the mammography appliance in a 45° position for an MLO image (mediolateral oblique). In the view according to FIG. 1B , the irradiation unit 2 is deflected by 45° relative to the longitudinal direction 4 . FIG. 1C shows the irradiation situation for a stereotactic examination performed concomitantly with a biopsy. During this stereotactic examination, the irradiation unit is usually swiveled ±10° or ±15° relative to the longitudinal direction 4 . The position shown in FIG. 1A is also described as the craniocaudal (CC) position, and the position shown in FIG. 1B is also described as the mediolateral oblique (MLO) position.
[0029] The different variants of the mammography appliance described here are usually embodied in such a way that they can be used for all irradiation variants. A modular design of the mammography appliance is provided so that alternatively in each case only certain irradiation situations are possible. With a pure screening system, for example, there is no separate swivelability and the irradiation unit is fixed relative to the object table. With a stereotactic system, the swiveling movement of the irradiation unit 2 is restricted, for example, by a stop, to a swivel movement of ±10° or ±15°. With a system, which is also provided for tomosynthesis, continuous movement is provided over a large angular range. The concepts described in the following for the design of the mammography appliance relate to a modular design with which optionally the respective mammography appliances for the different applications can be specified.
[0030] The mammography appliance includes a stand 6 , to which is attached an appliance rack 8 (see dashed line in FIG. 3 ). The appliance rack 8 has the irradiation unit 2 , a compression unit 10 , a bearing element 12 and a C-arm support arm 14 , which is also referred to as a C-arm for short. Arranged on the bearing element 12 , are an object table 16 and the compression unit 10 . The compression unit 10 includes a compression plate 18 , which is arranged displaceably relative to the object table 16 . A type of rail guide is provided in the compression unit 10 .
[0031] One end of the C-arm 14 is attached to the bearing element 12 so that the mounting end of the C-arm formed is attached and the C-arm can rotate about a horizontal axis 22 (see in particular FIGS. 2 , 3 ). At its other end, the C-arm bears the irradiation unit 2 . The irradiation unit 2 includes an X-ray tube and a diaphragm, wherein the X-ray tube emits soft X-ray radiation when in operation.
[0032] The C-arm 14 is a telescopic arm and has an extendable telescopic arm 24 on the end-side of which the irradiation unit 2 is arranged. The retraction and extension of the telescopic arm 24 causes a swivel movement of irradiation unit 2 to take place. The swivel movement facilitated by the telescopic arm 24 takes place in a swivel region required for the stereotactic examination. For a stereotactic examination, it is sufficient to retract or extend the telescopic arm. The C-arm 14 itself is not swiveled. The telescopic system establishes predefined stop positions for the irradiation unit 2 , which it then adopts alternately in each case. ( FIG. 1C ). Similarly, with a tomosynthesis examination, it is only necessary to move the telescopic arm 24 in order to swivel the irradiation unit 2 by ±25°.
[0033] If an MLO examination is desired, the entire C-arm 14 is swiveled about the horizontal axis 22 without the telescopic arm being moved (see FIG. 1B ).
[0034] The compression unit 10 is connected to the bearing element 12 , whereby here preferably joint rotatability with the C-arm 14 is facilitated so that the irradiation unit 2 is always aligned in the same orientation to the object table 16 ( FIG. 1B ). The bearing element 12 is formed by a bearing shaft connected to the stand, which is encompassed in a sleeve-like way by a rotatable bearing shell. The bearing shell forms the mounting end of the C-arm 14 . Simultaneously, the compression unit 10 is firmly mechanically connected to this bearing shell so that no relative motion is enabled between the mounting end of the C-arm 14 and the compression unit 10 .
[0035] Alternatively, the compression unit 10 is rotatably mounted about the horizontal axis 22 independently of the C-arm 14 . It is possible to dispense with the telescopic embodiment of the C-arm 14 and to swivel the C-arm 14 during a stereotactic examination and simultaneously leave the compression unit 10 in the horizontal alignment as is usual during a stereotactic examination.
[0036] As shown in FIG. 1A-1C , the stand 6 includes a lifting or telescopic device so that vertical adjustment is possible. The bearing element 12 is attached to an extensible lifting element 25 . The appliance rack 8 is substantially arranged above the stand 6 or substantially abuts the stand 6 commencing with the bearing element 12 .
[0037] In an alternative embodiment, as shown in FIG. 3 , the stand 6 is not vertically adjustable. Instead, the appliance rack 8 is vertically adjustable relative to the stand 6 , as indicated by a double arrow. The bearing element 12 is displaceable in the longitudinal direction 4 .
[0038] The support arm, as a C-arm 14 , lies within a swivel plane perpendicular to the horizontal axis 22 . The C-arm 14 clamps a plane perpendicular to the horizontal axis 22 . The support arm 14 does not protrude or only protrudes slightly forward from the stand 6 so that here only low leverage forces are exerted on the stand. The embodiment of the C-arm 14 achieves a structurally very stable design, which also facilitates the necessary swivel movements.
[0039] A further decisive advantage of the C-arm-type embodiment can be seen in that created between the two ends of the C-arm is a free space in which no support elements are arranged. The free space is utilized in the sense of a high degree of user friendliness to the effect that arranged on the stand 6 there is a display and/or operator panel 26 , which is visible to the operating personnel from the front, and independently of the respective rotary position of the irradiation unit 2 . As shown in FIG. 3 , the display field 26 is hereby arranged above the compression unit 10 and below the irradiation unit 2 on the center of the stand 6 .
[0040] As can be seen in particular in the side view in FIG. 3 , the C-arm 14 is placed directly in front of the front side of the stand 6 and between the stand 6 and the compression unit 10 . The design forms an interspace between the compression unit 10 and the stand 6 , which is used as a parking space 28 for a biopsy unit 30 .
[0041] An appliance rack 8 with an integrated biopsy unit 30 can be seen in FIGS. 4A , 4 B. The biopsy unit 30 includes a biopsy support column 32 to which a holder 36 for a punch biopsy appliance 37 is fixed. A biopsy compression plate 34 is provided which can be moved toward the object table 16 .
[0042] If a biopsy is to be performed, the biopsy unit 30 is swiveled into the operational or biopsy position provided in FIG. 4A . The breast to be treated is hereby fixed between the object table 16 and the biopsy compression plate 34 . The biopsy is performed in that a biopsy needle is introduced and tissue samples taken. X-ray images can be produced before and after the biopsy and optionally concomitantly with the biopsy.
[0043] After the end of the biopsy, the biopsy unit 30 is moved into its parked position and placed in the parking space 28 . In the exemplary embodiment according to FIGS. 4A and 4B , only one swivel movement is required to move the biopsy unit 30 from the parked position into the biopsy position. For this, the biopsy unit 30 is attached to a swivel arm 38 , which is arranged swivelably on the compression unit 10 .
[0044] FIGS. 5A-5C show different variants of the mammography appliance. With the embodiment according to FIG. 5A , the stand is vertically adjustable and the appliance rack 8 is connected by the bearing element 12 to the stand 6 and arranged above the stand 6 .
[0045] With the variant according to FIG. 5B , the appliance rack 8 is arranged directly in front of the front side of the stand 6 . The appliance rack 8 is vertically adjustable relative to the stand 6 . The two variants in FIGS. 5A , 5 B are provided for floor assembly. FIG. 5C now shows a variant for ceiling assembly in which the stand 6 embodied as a lifting system is attached to the ceiling. With this variant, once again the irradiation unit 2 is arranged above the object table 16 . Here, the stand 6 extends as far as the lower region of the C-arm 14 , on which the bearing element 12 (not shown in any more detail here) is provided in order to facilitate the swiveling movement.
[0046] While the invention has been described above by reference to various embodiments, it should be understood that many changes and modifications can be made without departing from the scope of the invention. It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. | To permit a compact and structurally simple design of a mammography appliance, an irradiation unit is secured on a C-arm, which lies in a swivel plane that is perpendicular to a horizontal axis. In this way, only slight mechanical leverages act on the support arm. At the same time, the C-arm design creates a free space, which is used in particular also for the arrangement of a display and/or control panel and for the arrangement of a biopsy unit. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of copending application No. 764,760 filed Aug. 12, 1985, by Janssen et al. for LARGE FRAME VISIBLE INDEX SYSTEM (now abandoned).
BACKGROUND OF THE INVENTION
This invention relates to visible index systems and more particularly relates to large frame visible index record systems wherein a plurality of record cards or card holders are pivotally mounted on a frame or tray in an overlapped edgewise spaced arrangement.
Visible index systems of this general type are described, for example, in U.S. Pat. No. 2,975,537 to Reid et al. and U.S. Pat. No. 2,217,018 to Hopkins. The Reid et al. patent illustrates a visible index system utilizing record cards. The Hopkins patent illustrates a visible index system using pocket card holders upon which a record card or cards may be removably mounted. Visible index systems of this type are applicable to virtually any record keeping function and provide the convenience of high visibility and ready removability. Metal hinges on the cards or card pockets are pivotally mounted on resilient spring steel hangers. The hangers have ends which spring into side channels of the type shown in the Reid et al. patent mentioned above or other suitable retainers. for the hanger ends. With the Reid et al. type of arrangement the cards or card holders are slidable in the mounting tray.
U.S. Pat. No. 2,537,268 to Hall and U.S. Pat. No. 3,274,715 to Janssen illustrate a modified mounting system wherein the wire hangers are received in separate notches in the frame or tray for non-slidable mounting.
Another version of the non-slidable mounting of wire hangers in a panel or tray is illustrated by way of example in U.S. Pat. No. 2,650,594 to Heilman. According to the arrangement disclosed in that patent, a tray intended for vertical mounting is provided with a series of upwardly extending tongues struck from the tray. Mounting rods are dropped or snapped into the openings between the upper ends of the tongues and the wall of the tray. By virtue of the particular mode of mounting, it is not necessary that the rods be resilient.
The use of visible index systems in hospital type applications is well known. Another application of visible index systems is in connection with machinery maintenance where such systems may be used to record, preserve and present such information as maintenance inspections schedules, history of repair, equipment records and the like information. In certain situations, such as with the maintenance and repair of automotive vehicles and aircraft, the recorded information is of such a nature that relatively large capacity visible index systems are desirable.
In such instances, it has been common practice to merely multiply the size of the tray and the number of cards and card holders. For example, visible index systems are available which utilize multiple columns of display cards on a large single frame or tray. Thus, a single large tray may contain as many as 5 columns of display cards and each column may contain as many as 100 cards. According to present practices, such large card holdres are carried by multiple wire hangers attached to the top edge thereof by a pair of hinges for each wire hanger. It is not unusual to use an array containing 100 card holders attached to 500 separate wire hangers. While such systems are satisfactory in a general sense, the manufacturing assembly of a system containing such a large number of hangers is time consuming and costly in a relative sense. In addition, the maintenance of such systems poses problems.
SUMMARY OF THE INVENTION
It is a feature of the present invention that the same large volume of information may be maintained in a visible card index system utilizing a fraction of the number of wire hangers which were previously deemed to be necessary. As a result, the manufacturing assembly time and cost may be significantly reduced.
It is a primary object of the invention to provide a visible index system for cards or pocket cards having an improved means of mounting the cards or pocket cards to the frame or tray by means of flexible wire hangers.
It is another object of the invention to provide an improved visible card index system for presenting a large volume of information and number of index cards mounted on resilient wire card hangers in such a manner as to permit the usage of a significantly lesser number of hangers than previously required to handle the same volume of information and number of display cards.
It is another object of the present invention to provide a novel improved visible index system for pocket cards having resilient wire hanges which are received in individual mounting means which peripherally surround the hanger portion received therein.
It is another object of the invention to provide an improved visible index system for cards or pocket cards hingedly mounted to a support or tray by means of mounting means substantially entirely peripherally surrounding the hanger and providing not only pivotal securement but also lateral restraint for the cards or pocket cards hingedly mounted therein.
It is another object of the invention to provide an improved visible index system for cards or pocket cards of large size including an improved mounting means for hingedly attaching the card or pocket card to the mounting panel or tray through the use of a resilient wire hanger and mounting means which substantially completely surround the wire hanger at a multiplicity of positions along the length of the wire hanger including locations intermediate the ends thereof.
It is another object of the invention to provide an improved visible index system of the type wherein cards or pocket cards are hingedly mounted to a support panel or tray including improved mounting means comprising hanger holders struck from the tray and substantially completely peripherally surrounding the hanger at spaced positions.
It is another object of the invention to provide a visible card index system for hingedly mounting a plurality of card means on a frame using a multiplicity of resilient wire hangers disposed in spaced parallel relationship and each supporting a pair of hinges attached to an edge of a car means with the wire hangers extending through each of the pair of hinges and having spaced end sections extending beyond the hinges, the frame means having attached thereto a pair of spaced intermediate mounting means disposed in substantially parallel relationship on axes substantially perpendicular to the axes of the wire hangers with each hanger passing through a pair of such spaced intermediate mounting means, the mounting means providing substantially complete peripheral containment of the hangers, the frame means also including a pair of spaced end mounting means disposed in substantial parallel relationship to said intermediate mounting means with the end mounting means receiving the end sections of the hangers, and the hangers being capable of flexure to permit axial insertion into and removal from the end mounting means.
It is another object of the invention to provide a visible card index system of the foregoing type wherein the hinges are disposed adjacent the intermediate mounting means to limit lateral movement of the cards or card holders attached to the hinges and the end mounting means include means for abutting the end sections of the hangers received therein to limit lateral movement of the hangers.
These and further objects and advantages of the invention will become apparent from the following specification and claims and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially broken away plan view showing a visible index system according to one embodiment of the invention;
FIG. 2 is a partial vertical section through the mounting frame or tray of FIG. 1 along the line 2--2 showing details of a wire hanger securing dimple;
FIG. 3 is a plan view partially broken away showing a modified embodiment of a visible card index constructed according to the invention;
FIG. 4 is a partial vertical section taken along the line 4--4 of FIG. 3 showing details of the fastening strap for the wire hanger;
FIG. 5 is a partial vertical section through another embodiment of mounting means for a wire hanger in a visible index system according to the invention;
FIG. 6 is a partial plan view of a preferred embodiment of a large visible index system constructed according to the invention;
FIG. 7 is a perspective view showing details of the mounting straps, hanger and hinge of the visible card index system of FIG. 6;
FIG. 8 is a partial perspective view showing still another embodiment of securement or mounting for a wire hanger for the ends of a visible index system constructed according to the invention;
FIG. 9 is a vertical section through the embodiment of FIG. 8 showing the relationship of the card, hinge and wire hanger to the mounting means;
FIG. 10 is a partial perspective view showing another embodiment of hanger securing strap;
FIG. 11 is a partial perspective view showing a still further embodiment of hanger securing device;
FIG. 12 is an exploded perspective view showing a portion of a tray or panel and a portion of a strap shaped to form a still additional embodiment of hanger securing device; and
FIG. 13 is a vertical section showing the hanger securing device of FIG. 12 is an assembled position of hanger wires extending therethrough;
FIG. 14 is a view similar to FIGS. 1 and 6 of an embodiment of the invention which incorporates features from both the FIG. 1 and FIG. 6 embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown a visible index system comprising a mounting panel, frame or tray 10 carrying a relatively large index card 12. The tray illustrated is formed of metal but may be formed of any suitable material. It will be understood that while only a single index card is shown a plurality of cards will ordinarily be mounted in overlapping relationship. It will also be understood that while a card is illustrated a pocket card may also be used. The card 12 has conventional hinges 14 attached to the upper edge thereof and secured by reverse bent lugs 6. A resilient wire hanger 18 extends through the barrels 20 of the hinges 14.
The ends of the wire hanger 18 are received in dimples 22 which are struck from a pair of generally parallel metal strips 24 which may be fastened to the tray 10 in any suitable manner such as by spot welding. As shown in FIG. 1, the mounting strips 24 are spaced by a distance less the width of the card 12. This permits placement of the hinges inward of the outer edges of the card to provide optimum card support according to this particular embodiment of the invention.
Referring to FIG. 2, it will be seen that the dimple indicated generally at 22 is struck from the strip 24 to provide a generally semicircular receptacle 26 which has a curvate top wall 30 and a generally quadrispherical end 32. The dimples 22 secure the wire hangers against movement (radial to the longitudinal axis of the hanger) as well as against lateral movement along the axis. The mounting means provides complete perpheral containment of the hanger ends received therein.
The index cards 12 may be attached to the tray 10 by flexing the spring wire hanger 18 so that the ends 28 thereof enter the receptacles 26 formed by the dimples 22. While the dimples 22 shown in the embodiment of FIGS. 1 and 2 are formed in strips 24 which are fastened to the tray 10, it is also a feature of the invention that the dimples may be struck directly from the tray 10 whereby separate strips may be eliminated.
Referring to FIG. 3, there is shown another embodiment of the invention comprising a tray 10 carrying a card 12. The card 12 depends from a wire hanger 18 upon which are mounted conventional hinges 14 of the type described in connection with FIG. 1. According to this embodiment of the invention, the dimples shown in FIGS. 1 and 2 are replaced by two vertical rows of spaced generally parallel securing straps indicated generally at 34. As will be seen from FIG. 4, each securing strap 34 is struck from the tray 10 to form a bight 36 to receive the end 28 of the wire hanger 18.
A pair of spaced generally parallel elongated strips 38 are attached to the panel 10 with the inner edges 40 of the strips adjacent the outer edges of the straps 34. The strips 40 may be attached to the tray 10 in any suitable manner such as by spot welding or the like. The inner edges 40 of the strips 38 provide abutments for the ends 28 of the wire hangers 18 to limit and prevent lateral movement thereof.
Referring to FIG. 5, there is shown still another embodiment of the invention wherein the abutment strips 38 shown in FIG. 3 may be replaced by channels 42 having reverse bent outer edges terminating in flanges 44 which receive the ends 28 of the wire hangers 18. This embodiment of the invention has the advantage of disposing the wire hanger 18 in a spaced relationship to the tray 10 to provide a freer movement of the hinges 14.
Referring to FIG. 10, there is shown a further embodiment of strap which may replace the straps 34 shown in FIGS. 3 and 4. Thus, in FIG. 10, there is seen a metal strip 11 having inverted J-shaped straps 13 struck therefrom to leave slots or openings 15 in the strip 11. The upper end 17 of the strap 13 is attached to the upper edge 19a of the slot 15 whereas the lower or free edge 19 of the strap is spaced from the lower slot edge 21. This type of strap having a free end or edge may be utilized where the nature of the metal of which the panel, tray or strip is formed is not readily susceptible of the workability required to form a continuous strap of the type shown at 34 in FIG. 4. The free or lower edge 19 of the strap 13 in FIG. 10 may be bent so as to be adjacent the plane of the upper surface of the strip 11 to provide substantially complete peripheral contaiment of the hanger. The arrangement illustrated in FIG. 10 using the inverted "J" strap shape and slot permits the provision of straps of a relatively large diameter while still providing substantially complete containment of the hanger. While the strap 13 shown in FIG. 10 is referred to as an inverted "J" strap, it will be appreciated that from, an edge view, it gives virtually a "U" shaped appearance. The elongated strip 11 may be fastened to the tray by spot welding, riveting or other suitable techique. While the strap is described as metal, it will be apparent that other materials such as synthetic resins may also be utilized for either or both the strip and the tray. The strip 11 may be mounted adjacent to end or edge strips such as strips 38 in FIG. 3 to provide lateral securement of the hanger ends.
Referring to FIGS. 12 and 13, there is shown still another embodiment for forming straps of the same general type as the strap 34 illustrated in FIG. 4. Referring to FIGS. 12 and 13, the tray 23 may be provided with a series of generally rectangular openings 25 disposed at positioned where it is desired to support the hangers. Parallel rows of openings 25 may be provided at two or more spaced positions on the tray extending along lines disposed vertically to the desired hanger axes. Associated with each row of openings 25 is an elongated metal strip 27 having a width slightly smaller than the lateral width of the openings 25. A series of U-shaped bights 29 are struck in the strip 27 at spacings corresponding to the spacings of the openings 25. The bights 29 are dimensioned and positioned to extend through the openings 25 as illustrated in FIG. 13. In this assembled form, the bights 29 form straps to support wire hangers 31. The strip 27 may be secured to the tray 23 in any suitable manner such as spot welding, riveting or the like. Again, the strap and tray provide substantially complete peripheral containment of the hanger. The strips 27 may be mounted adjacent lateral containment strips of the type illustrated at 38 in FIG. 3 or may be associated with channels of the type illustrated at 42 in FIG. 5. As a still further alternative, the strips 27 may have struck therefrom quadrispherical dimples such as shown in FIGS. 1 and 2; and these may extend through the openings 25.
Still another embodiment of means for securing the hangers is illustrated in FIG. 11. According to this embodiment of the invention, an elongated generally U-shaped channel member 33 is provided with spaced generally parallel side walls 35 and 37 joined by a top wall 39. The side walls 35 and 37 are formed with outwardly extending flanges 41 and 43. Spaced apertures 45 are provided in the side walls 35 and 37 immediately adjacent the under surface 47 of the top wall 39. Apertures 45 are adapted to receive wire hangers. The placement of the apertures 45 immediately adjacent the under surface 47 of the top wall 39 minimizes the height of the securing means above the hangers. The channel members 33 may be mounted on a suitable panel or tray by any suitable means such as spot welding, riveting, or the like as a substitute for the hanger mounting means illustrated in FIGS. 3, 4, 5, 10, 12, and 13, by the way of example. If desired, the apertures 45 in the outermost side walls 35 of the channel members 33 may be eliminated so that the channel members 33 may serve not only to peripherally contain the hangers but also as a lateral abutment.
Referring to FIG. 6, there is seen another preferred embodiment of the invention which is particularly adapted for use in large size index display systems. According to this embodiment of the invention, a tray 10 has mounted thereon a series of cards 12. The cards 12 are carried by hinges 14 of the type described in connection with FIG. 1. It will be seen that according to this embodiment of the invention four hinges 14 are provided at spaced intervals along the top edge of the large card 12. Hinges 14 receive in their barrels 20 a relatively long resilient wire hanger 18. The ends of the hanger 18 are received beneath flanges 44 carried by channels 42 in the manner described in detail in connection with FIG. 5. Intermediate the ends 28 of the wire hangers 18 and preferably adjacent the hinges 14 are two vertical rows of spaced straps indicated generally at 34.
The straps 34 illustrated in FIG. 6 are illustrated in detail in FIGS. 4 and 7 and comprise bights 36 struck from the tray 10. FIG. 7 shows the strap 34 having the edge of its bight 36 adjacent the edge of the barrel 20 of the hinge 14 attached by lugs 16 to card 12. The adjacent arrangement of the straps 34 and hinges 14 limits and prevents lateral movement of the card with respect to the tray. This provision of lateral restraint intermediate the ends of the hanger enhances the integrity, strength and durability of the visible index system.
As will be seen from FIG. 6, the innermost hinges 14 are mounted inwardly of the inner rows 35a of adjacent straps 34. The outermost hinges 14 are mounted inwardly of the outermost roes 39a of straps 34. With this arrangement, the two left hinges 14 prevent leftward lateral movement of the card 12 with respect to the tray 10 as seen in FIG. 6 while the two right hinges 14 prevent rightward movement of the card 12 with respect to the tray 10. The card 12 may be readily removed by flexure of the wire hanger 18 to permit an end 28 to spring free of its restraining flange 44. Once an end is thus freed, the hanger may be axially withdrawn from the straps and hinges to permit removal of the card.
The embodiment of the invention illustrated in FIG. 6 is particularly adapted to a variety of sizes of large cards and trays. The provision of the multiple spaced rows of straps 34 provides rigidity of mounting for the hanger and prevents inadvertent flexure of the hanger resulting in undesired detachment of the card from the tray. While four rows of hinges and straps are illustrated, additional rows may be provided where desired.
It will be appreciated that the flanges 44 illustrated in FIG. 6 may be replaced with the dimples illustrated in FIGS. 1 and 2 as an alternate means of securing the ends of the wire hangers (a visible index system of this character is illustrated in FIG. 14 and identified by reference character 56). Such dimples may be provided either in separate parallel metal strips of the type illustrated in FIGS. 1 and 2 or may be struck directly from the tray as descriged in connection with the embodiment of the invention illustrated in FIGS. 1 and 2. Similarly, the straps 34 in FIG. 7 may be replaced with securing means such as the straps illustrated in FIGS. 10, 12 and 13 or securing means in the shape of U-shaped channels such as illustrated in FIG. 11.
A visible index system contructed according to this embodiment of the invention permits the convenient compiling, preserving, and presentation of a high volume of data or information. The system is efficiently usable in a large format which is easily assembled and at the same time provides a structural integrity not readily attainable with conventional systems using a very large number of hangers and cards or pocket cards. The construction lends itself to variations in size and configuration without sacrifice of record visibility, integrity or security.
Referring to FIGS. 8 and 9, there is shown still another embodiment of end mounting for wire hangers arranged according to the invention. In FIGS. 8 and 9, the tray 10 is provided at its side edges 46 with upstanding flanges 48. The upstanding flanges 48 have their upper ends bent in a reverse U-shaped fashion to form bights 50 and downwardly extending walls 52. The walls 52 are provided with spaced apertures 54 to receive the ends 28 of wire hangers 18. Cards 12 are fastened to the wire hangers 18 by means of hinges 14 as described in detail in connection with FIG. 1 and 2 and as illustrated in detail in FIG. 7. Such cards or card holders are supported according to the invention as shown in FIG. 6 which illustrates the intermediate mounting straps 34.
It will be apparent from the foregoing that the improved visible card index system of the invention provides an effective and economical system for recording, preserving, and presenting a large volume of information while eliminating the need for potentially hundreds of wire hangers. The new system entails the use of large cards or pocket cards hingedly mounted on large panel means or frames through the use of both end and intermediate mounting means disposed to adequately support relatively long hangers and limit lateral movement of both the cards or pocket cards as well as the hangers. The mounting means provide for substantially complete peripheral containment of the hangers. The hangers may be mounted on the panel means or frame by flexure of the hangers to permit axial entry into the various mounting means. The system is particularly well adapted for use with metal panel and mounting means wherein the individual mounting devices may be simply struck from the metal in a highly economical fashion. Because of the significant reduction in the number of cards or pocket cards and associated wire hangers, the manufacture of the device is simplified and reduced in cost.
The invention may be embodied in many specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | Visible index systems which include a support and hanger wires for detachably affixing cards and pocket cards to the support in an overlapping arrangement. The arrangement for fixing the hanger wires to the support is so constructed that each card or pocket card is independently supported, and lateral movement of the hanger wires is precluded as is lateral movement of the cards along those wires. | 1 |
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not applicable.
REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] The present invention relates generally to a reciprocating pneumatic tool, and more particularly to an innovative one which is designed with an integrated module of a cylinder and flow reversing assembly.
[0007] 2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
[0008] Reciprocating pneumatic tools such as pneumatic saws, pneumatic hammers and pneumatic cutters, are available with different functions depending on the shapes of the ends.
[0009] According to the operating principle of reciprocating pneumatic tools, the source of air is firstly guided into the tool, then the opening/closing of air pressure is controlled by a control valve, and an actuating module is used for automatic reversing of air pressure, enabling the reciprocating movement of a piston rod together with the ends of tools (e.g.: saw blade, punch hammer).
[0010] In view of the structural design of the reciprocating pneumatic tool, the number of components affects directly the cost and efficiency of fabrication, processing and assembly, and the defective fabrication and assembly increase with the growing number of components. Thus, due attentions must be paid to the technical issue of minimizing the structural members in the process of R&D and design.
[0011] As for the structural design of a conventional reciprocating pneumatic tool similar to the present invention, Taiwan patent claim No. 96133970: “A Reciprocating Pneumatic Tool” can be referenced, and the general configuration and pattern are shown therein. The flow reversing assembly of the prior art is structurally composed of a top plate, a principal pedestal and a base plate. The flow reversing assembly is superposed onto the surface of a cylinder. It is found from actual applications that the flow reversing assembly of the prior art must be provided with several overlapped plates, and then superposed onto a cylinder. Such an overlapping structure brings about much increase of fabrication, processing and assembly cost of structural members as well as poorer efficiency, meanwhile a higher defect may occur against the performance and quality of finished products. Furthermore, in order to realize accurate fitness and high air-tightness of unit components, the assembly surface of every unit component will be subject to time-consuming and costly precise processing, leading to higher fabrication cost with poorer industrial and economic benefits.
[0012] Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
[0013] Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products.
BRIEF SUMMARY OF THE INVENTION
[0014] The present invention allows the reversible actuating slot to be recessed integrally onto the air pressure guiding seat. Moreover, the air pressure guiding seat is separated from the cylinder body via said partition board. With this unique structural design as compared with the prior art, the partition board, air pressure guiding seat's assembly end surface and cylinder body's inner assembly end can be grinded precisely to realize accurate fitness of various components. Of which the partition board of a planar sheet permits very easy and precise grinding, so the integrated module of cylinder and flow reversing assembly enables to simplify the processing and mass production, reduce the fabrication/processing cost, shorten the assembly time and minimize the defect with better applicability and industrial benefits.
[0015] Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0016] FIG. 1 is an assembled perspective external view of the reciprocating pneumatic tool of the present invention.
[0017] FIG. 2 is an exploded perspective view of the reciprocating pneumatic tool of the present invention.
[0018] FIG. 3 is an exploded perspective view of the integrated module of cylinder and reversing assembly of the present invention.
[0019] FIG. 4 is an assembled sectional view of the reciprocating pneumatic tool of the present invention.
[0020] FIG. 5 is an exploded sectional view of the integrated module of cylinder and reversing assembly of the present invention.
[0021] FIG. 6 is an air inlet schematic view 1 of the present invention.
[0022] FIG. 7 is an air inlet schematic view 2 of the present invention.
[0023] FIG. 8 is air inlet schematic view 3 of the present invention.
[0024] FIG. 9 is an exhaust schematic view of the present invention.
[0025] FIG. 10 is a B-B′ sectional view of FIG. 9 .
[0026] FIG. 11 is an application view wherein the piston rod guiding tube and cylinder body are assembled fixedly.
DETAILED DESCRIPTION OF THE INVENTION
[0027] FIGS. 1-5 depict preferred embodiments of an integrated module of cylinder and reversing assembly of a reciprocating pneumatic tool of the present invention, which, however, are provided for only explanatory objective for patent claims. Said integrated module A of cylinder and reversing assembly is arranged between an air supply end 121 of air pressure control module 12 and a guide outlet 131 of piston rod 13 in the groove 11 of reciprocating pneumatic tool 10 (marked in FIG. 4 ). The piston rod 13 is provided with a piston 132 and a tool assembly portion 133 .
[0028] The integrated module A of cylinder and reversing assembly comprises a cylinder body 20 , a hollow body shaping an inner assembly end 21 , an external end 22 , a cylinder wall 23 and a chamber 24 . Of which, the chamber 24 is used for accommodating the piston 132 of the piston rod 13 . Several air flow ducts 25 are set internally and extended along the cylinder wall 23 . Moreover, air vents 26 are opened laterally onto two opposite sides of the cylinder wall 23 . A reducing piston rod guiding tube 27 is protruded on the external end 22 .
[0029] An air pressure guiding seat 30 has a seat body 31 and an air inlet end 32 . A main air inlet guide hole 33 is penetrated into air inlet end 32 is connected with an air supply end 121 of the air pressure control module 12 . The seat body 31 is provided with an assembly end surface 34 , and flow ducts 35 are set onto two opposite sides of the assembly end surface 34 . Said flow duct 35 is connected obliquely with the main air inlet guide hole 33 via the secondary air inlet guide hole 36 .
[0030] A reversible actuating slot 40 is recessed into the assembly end surface 34 of the seat body 31 , with its inner end connected with the main air inlet guide hole 33 . A lateral through-hole 41 set on the reversible actuating slot 40 runs through the side wall of the seat body 31 . Oblique through-holes 42 set on two sides of the inner wall of the reversible actuating slot 40 run through the assembly end surface 34 of the seat body 31 . Two sides of the reversible actuating slot 40 are connected with the flow duct 35 on the assembly end surface 34 .
[0031] A reversing brake block 50 is accommodated movably into the reversible actuating slot 40 , and reducing flange 51 is formed onto one end of the reversing brake block 50 correspondingly to the reversible actuating slot 40 (shown in FIGS. 3 , 5 ), so as to increase the lateral area pushed by air pressure; the lateral through-hole 41 on the reversible actuating slot 40 could maintain smooth lifting of the reversing brake block 50 by releasing air accumulated in the reversible actuating slot 40 .
[0032] A partition board 60 is assembled fixedly between the assembly end surface 34 on the seat body 31 of the air pressure guiding seat 30 and the inner assembly end 21 of the cylinder body 20 . A through-hole 61 of a diameter smaller than external diameter of the reversing brake block 50 is set on the center of the partition board 60 . Two flow troughs 62 spaced onto the partition board 60 are connected with the air flow duct 25 on the cylinder wall 23 of the cylinder body 20 and the oblique through-hole 42 on the seat body 31 of the air pressure guiding seat 30 .
[0033] Referring to FIG. 3 , a plurality of bolt holes 71 , 72 are set correspondingly on the air pressure guiding seat 30 and partition board 60 . A positioning threaded hole 73 is set correspondingly to the inner assembly end 21 of the cylinder body 20 , such that the bolt holes 71 , 72 are fixed by the bolt 74 and locked into the positioning threaded hole 73 , enabling secure assembly of the air pressure guiding seat 30 , partition board 60 and cylinder body 20 .
[0034] Referring to FIG. 5 , the reversible actuating slot 40 of a stepped recess space is defined into a pinched portion 43 and an flared portion 44 , so that said lateral through-hole 41 is set correspondingly to the flared portion 44 . The reversing brake block 50 comprises of a reduced portion 52 and an expanded portion 53 . The expanded portion 53 is placed correspondingly to the pinched portion 43 of the reversible actuating slot 40 , whilst the reduced portion 52 is mated with the flared portion 44 of the reversible actuating slot 40 . With the design of a stepped pattern, a differential pressure area of bigger top and smaller bottom is formed in response to the actuating flow path design of the reversing brake block 50 (namely, the top is subject to central pressure, and the bottom subject to central and lateral pressure).
[0035] Referring to FIGS. 2 and 4 , a damper is arranged within the groove 11 of the reciprocating pneumatic tool 10 . Said damper comprises of a central buffer 81 (e.g. a spiral spring) set between the seat body 31 of air pressure guiding seat 30 and air supply end 121 of air pressure control module 12 , as well as a front buffer 82 (e.g. a spiral spring) set between the external end 22 of the cylinder body 20 and an end wall of the groove 11 .
[0036] Of which, the piston rod guiding tube 27 on the external end 22 of the cylinder body 20 and the cylinder body 20 may be prefabricated (shown in FIGS. 2-9 ), or the piston rod guiding tube 27 B shown in FIG. 11 is set into an assembled positioning structure, wherein the piston rod guiding tube 27 B and the external end 22 of the cylinder body 20 can be fixed securely by bolt 28 .
[0037] Moreover, the cylinder body 20 , air pressure guiding seat 30 and partition board 60 are provided with trimmed edges 91 , 92 , 93 . The inner wall opposite to the groove 11 of the reciprocating pneumatic tool 10 is of cylindrical cross section, such that an exhaust passage 94 is formed between the trimmed edges 91 , 92 , 93 and the inner wall of cylindrical groove 11 (shown in FIGS. 9 and 10 ).
[0038] Based upon above-specified structure, the present invention is operated as follows:
[0039] Referring to FIG. 6 , said reciprocating pneumatic tool 10 is operated in such a manner that the control switch 14 is pressed (shown by arrow L 1 ) to open air flow path of the air pressure control module 12 . Then air pressure W will pass through air supply end 121 of air pressure control module 12 and air inlet end 32 into air pressure guiding seat 30 and integrated module A of cylinder and reversing assembly. With the help of air flow path design of the integrated module A, the piston 132 and piston rod 13 along with the actuating tool (e.g.: saw) are driven for rapid reciprocating movement with reference to the accompanying drawings.
[0040] Referring firstly to FIG. 6 , when air pressure W is guided from air pressure guiding seat 30 into the integrated module A of cylinder and reversing assembly, it will pass through the oblique secondary air inlet guide hole 36 and flow duct 35 into the reversible actuating slot 40 . In such a case, air pressure W will push the reversing brake block 50 upwards to drive the top of the reversing brake block 50 to close the main air inlet guide hole 33 , on the other hand, air pressure W passes the through-hole 61 on the center of partition board 60 into the chamber 24 of the cylinder body 20 so as to push the piston 131 downwards.
[0041] Referring also to FIG. 7 , the sectional position is located at the air flow duct 25 of the cylinder body 20 . When the piston 132 is pushed downwards, air squeezed in the lower space of the chamber 24 will pass through air flow duct 25 on the cylinder wall 23 of the cylinder body 20 , then through the flow through 62 of the partition board 60 and the oblique through-hole 42 of the air pressure guiding seat 30 into the upper part of the reversible actuating slot 40 , thus pushing the reversing brake block 50 downwards (shown by arrow L 2 ).
[0042] Referring also to FIG. 8 , when the reversing brake block 50 is pushed downwards by air pressure W, air pressure W in main air inlet guide hole 33 can pass through oblique through-hole 42 , then through the flow through 62 of partition board 60 , air flow duct 25 of cylinder body 20 into the lower space of the chamber 24 , thus pushing the piston 132 upwards (shown by arrow L 3 ) for reversing movement.
[0043] Referring also to FIGS. 9 and 10 , when the piston 132 is pushed to the bottom, exhaust air flow W 2 will be discharged from air vent 26 on the chamber 24 to the exhaust passage 94 reserved on the cylinder body 20 .
[0044] The core design of the present invention lies in that, the reversible actuating slot 40 of the integrated module A is recessed integrally onto the air pressure guiding seat 30 , which is separated from the cylinder body 20 via said partition board 60 , thus simplifying the structural members and facilitating fabrication without changing the functions of guiding, reversing air and actuating the piston. | A reciprocating pneumatic tool has an integrated module of a cylinder and flow reversing assembly. The tool allows the reversible actuating slot to be recessed integrally onto the air pressure guiding seat. The air pressure guiding seat is separated from the cylinder body via a partition board. Compared with the prior art, the partition board, air pressure guiding seat's assembly end surface and cylinder body's inner assembly end can be grinded precisely to realize accurate fitness of various components. The partition board of a planar sheet permits very easy and precise grinding, so the integrated module of cylinder and flow reversing assembly enables simplification of the processing and mass production, reduction of the fabrication/processing cost, and shortening of the assembly time and minimization of the defect with better applicability and industrial benefits. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to Gram staining methods, and kits of reagents therefore.
Conventional Gram staining technique subjects the sample (frequently a specimen which has been smeared on a glass slide and dried) to four solutions in sequence:
(1) aqueous Gentian Violet (also called Crystal Violet, Hexamethyl Violet C.I. No. 42555),
(2) aqueous iodine-iodide (conventionally KI and I 2 in water),
(3) decolorizer (conventionally acetone admixed with ethanol or isopropanol), and
(4) counterstain (conventionally Safranin solution).
Handling of the iodine-iodide solution has been improved by the use of polyvinylpyrrolidone-iodine. Theories about how this technique distinguishes Gram Positive from Gram Negative bacteria have varied, but it is often stated that iodine forms a complex with Gentian Violet that is trapped by a barrier in Gram Positive cells that have been dehydrated and treated with mordant and iodine. In Gram Negative bacteria, the barrier is more penetrable, so that the solvent (decolorizer) extracts the iodine-Gentian Violet complex. Thus, it is a common recommendation to leave the iodine solution on the slide for at least one minute and then remove it by gently rinsing with cold tap water before introducing the decolorizer.
BRIEF DESCRIPTION OF THE INVENTION
It has been found that the aqueous iodine-iodide solution and decolorizer solution used in conventional Gram staining can be replaced by a single solution of iodine-iodide in an alcohol. This change permits less steps and also facilitates handling of the iodine-containing reagent.
The invention thus provides a method for the staining of a biological specimen to identify Gram Positive bacteria, which comprises:
(a) staining the biological specimen with Gentain Violet, and
(b) contacting the Gentain Violet stained specimen with a solution comprising iodine, an iodide salt and an alcohol solvent for a time sufficient to intensify the staining of Gram Positive bacteria and to decolorize Gram Negative bacteria.
Preferably, the contacting step (b) is followed by:
(c) counterstaining Gram Negative bacteria in the specimen with a Safranin solution.
The invention further provides a Gram staining kit which comprises:
(a) an aqueous Gentian Violet solution, and
(b) an alcoholic solution of iodine and an iodide salt.
Preferably, the kit further comprises:
(c) an aqueous Safranin solution.
DETAILED DESCRIPTION OF THE INVENTION
The aqueous Gentian Violet solution used in the present method and kit and the aqueous Safranin solution used in the present method and kit can be of conventional composition. Each may contain, in addition to water and the stain, one or more minor components, and especially organic co-solvents (e.g., 1.2 g Crystal Violet, 10 ml isopropanol, 2 g aniline in 100 ml solution with the balance water). The Safranin solution, particularly, can be stain (Safranin-0) at low concentration (e.g., 10 g/L) in water.
The alcoholic iodine-iodide solution preferably has three ingredients: alcohol solvent, elemental iodine and an iodide salt. The alcohol solvent can be any lower alcohol (e.g., methanol, ethanol, isopropanol, n-propanol, t-butanol), but is preferably ethanol. So long as the alcohol is the major component of the solvent, other miscible liquids (and especially water) may be present. It is preferred, however, to have low water content, such as in the 19:1 ethanol:water ratio found in the ethanol-water azeotrope (95% ethanol).
Iodine may be present in the alcohol solvent at any concentration up to the solubility limit, but it is preferred to use a controlled amount that has minimal iodine vapor pressure at room temperature (e.g., 1-5 g/L in 95% ethanol). Various inorganic iodide salts may be used, with NaI and KI being preferred because of the ready availability, and KI being especially preferred because of its conventional use in aqueous iodine-iodide solutions used for Gram staining. The iodide salt can be present up to its solubility limits in the solvent, with concentrations of 3-20 g/L being generally preferred. Overall, the molar ratio of I 2 to I - is not critical, but is preferably 1-3.
A representation formulation used below in Example 1 is:
______________________________________KI 6.6 g/L (solid)I.sub.2 3.3 g/L (solid)95% ethanol balance.______________________________________
It should be appreciated that I - can be converted in situ to I 2 with coventional oxidants, or I 2 reduced in situ of I - with conventional reductants; however, it is generally more convenient to introduce iodine and iodide salt separately. Iodine complexes can be used, but are not preferred.
In using such solution in the present method, one begins with dehydrated tissue in the conventional manner. Thus a thin, uniform smear is prepared on a microscope slide of specimen material from a culture or other source. Water is removed by air drying followed by heating the slide, or by the use of a dehydrating agent.
The dried specimen is then stained with Gentian Violet (Crystal Violet) solution in the conventional manner. For example, each slide can be flooded with the solution for one minute, and then washed gently with cold water. The alcoholic iodine-iodide solution is then applied, preferably first to rinse off water and then to flood the slide. It is also left on the slide for a minute or longer.
At this point, several possible routes can be taken. First, one can then apply a traditional decolorizer solution to assure that the Gentian Violet is fully removed from Gram Negative bacteria. Then, if desired, the Safranin counterstain can be applied. Second, one can proceed directly to washing the slide (for viewing Gram positive bacteria only) or to washing and counterstaining (for viewing Gram Positive and Gram Negative bacteria).
Certain benefits are obtained whether or not the separate decolorizer solution (and step) are omitted. First the iodine solution in alcohol has a much lower iodine vapor pressure than in aqueous iodine-iodide solutions. This prevents loss of iodine activity. Similar results are presently achieved by the use of polyvinylpyrrolidone-iodine complex (Povidone-Iodine) in water.
Certain benefits, however, are obtained in the embodiments of the present invention wherein no separate decolorization solution (or step) is employed. These involve, principally, the savings of time and materials. Additionally, the flammability of acetone-alcohol mixtures places restrictions upon shipment of certain conventional decolorizers that are avoided in some embodiments of the present invention.
The kit of the present invention can be packaged in a variety of ways. Presently, the iodine vapor pressure of aqueous iodine-iodide solutions places severe restrictions upon what type of container can be used. Thus, if such aqueous solutions were packaged in polyethylene, the iodine would permeate the polyethylene container walls and escape. Thus, after a storage period of three weeks, an effective iodine concentration would be lost. By contrast, the present alcohol-based iodine solutions can be stored in polyethylene containers for up to two months at 37° C. without detectable loss of iodine by thiosulfate titration.
EXAMPLE
A two liter solution was prepared from 13.2 g solid KI, 6.6 g solid iodine and two liters of 95% ethanol. Standard microscope slides, on which various bacteria (S. Aureus, S. Epidermis, E. Coli, or Pseudomona Aeruginosa) were pre-coated, were stained with a standard Gentian Violet solution (Crystal Violet, isopropanol, anilinie, water) and washed gently with cold water.
At this point, some of each group of slides were flooded with the above aqueous KI/iodine solution. After one minute, the slides were rinsed with cold water. Then they were treated with standard aqueous Safranin solution.
In such tests, the S. Aureus and S. Epidermis slides tested positive, showing the same violet staining of the Gram Positive bacteria as similar slides treated with aqueous KI/iodine and then decolorizer. The E. Coli and Pseudomona Aeruginosa slides tested negative with alcoholic KI/iodine solution used, with the Gram Negative bacteria appearing pink-red with the Safranin counterstain. | The present invention provides Gram staining methods and kits in which conventional aqueous iodine-iodide solutions and separate decolorizer solutions are replaced by storage stable alcoholic solutions of iodine-iodide. | 8 |
This is a Continuation of application Ser. No. 09/903,681 filed Jul. 13, 2000 (presently abandoned) which in turn is a Continuation of PCT/IE00/00008 filed Jan. 17, 2000.
INTRODUCTION
This invention relates to probiotic Bifidobacterium strains which have various applications in foodstuffs and in medicine. More particularly, the invention relates to probiotic strains of bifidobacteria which are capable of beneficially modifying and consequently alleviating observable symptoms in inflammatory disease.
Consumers are becoming increasingly aware of matters which may be necessary for maintenance of their environment, health and nutrition. In response, scientific research has focussed upon the roles that diet, stress, and modern medical practices (e.g. antibiotics and radiotherapy) may play in threatening human health. In particular, population dynamics shifting towards older societies are increasing the incidence of illnesses which may be caused by deficient or compromised microflora such as gastrointestinal tract (GIT) infections, constipation, irritable bowel syndrome (IBS), inflammatory bowel disease (IBD)—Crohn's disease and ulcerative colitis, food allergies, antibiotic-induced diarrhoea, cardiovascular disease, and certain cancers (e.g. colorectal cancer).
Probiotics have been defined as live microbial food supplements which beneficially affect the host by improving the intestinal microbial balance, or more broadly, as living micro-organisms, which upon ingestion in certain numbers, exert health effects beyond inherent basic nutrition. Cocktails of various micro-organisms, particularly species of Lactobacillus and Streptococcus , have traditionally been used in fermented dairy products to promote health.
In recent years the commercial manufacture and marketing of functional foods (foods which affect functions of the body in a targeted manner so as to bring about positive affects on physiology and nutrition), particularly probiotic (Acidophilus-Bifidus) yoghurts, has spread from the well-established Japanese niche market place into the lucrative and expanding European Union. While a number of probiotic bacteria of human origin are now being exploited commercially (e.g., L. acidophilus LA-1), many consumers, consumer organisations, and members of the scientific community are sceptical of such products and their publicised probiotic claims. The diary-food industry is therefore under considerable pressure to scientifically validate these new probiotic food products.
Criteria which have been suggested for the selection of potentially effective probiotic micro-organisms may be summarised as follows: human origin, non-pathogenic behaviour, resistance to technological processes (i.e., viability and activity in delivery vehicles), resistance to gastric acidity and bile toxicity, adhesion to gut epithelial tissue, ability to colonise the GIT, production of antimicrobial substances, ability to modulate immune responses, and the ability to influence metabolic activities (e.g., cholesterol assimilation, lactase activity, vitamin production) (Huis in't Veld J, Shortt C. Selection criteria for probiotic micro-organisms. In: Leeds, A. R., Rowland, I. R. eds. Gut Fora and Health—Past, Present and Future. London: The Royal Society of Medicine Press Ltd., 1996:19–26).
Bifidobacteria are one of several predominant culturable bacteria present in the colonic microflora.
The functions of endogenous bifidobacteria in the colon have not been completely elucidated. However, it is recognised that exclusively breast-fed infants have a reduced risk of diarrhoea compared with formula-fed infants. The fact that these infants have greater numbers of colonic bifidobacteria may in part explain this observed health advantage as the occupation of available niches in the GIT by large numbers of nonpathogenic bifidobacteria may help prevent bacterial infection. The pathogenesis of Crohn's disease is thought to be related to colonic bacterial microflora (Targan, S. and Shanahan, F. Inflammatory bowel disease: From bench to bedside. Williams and Wilkins 1994.) It has recently been found that patients suffering from active Crohn's disease have significantly less recoverable bifidobacteria in their faeces compared with healthy individuals. This reduction in bifidobacteria numbers was observed to be directly correlated with decreased levels of β-D galactosidase production and activity (Favier, C. et al, Dig. Dis. Sci. 1997;42:817–822). β-D galactosidase is an enzyme produced by bifidobacteria . These results support suggestions proposed in other studies that strains of bifidobacteria may play important roles in maintaining a balanced healthy intestinal microflora.
Bifidobacteria are considered to be probiotics as they are living organisms which exert healthy effects beyond basic nutrition when ingested in sufficient numbers. Numerous ingested bifidobacteria must reach the site of action in the gut in order to exert a probiotic effect. A minimum level of approximately 10 6 –10 7 viable bifidobacteria per gram intestinal contents has been suggested (Bouhnik, Y., Lait 1993: 73:241–247). There are reports in the literature which show that in vivo studies completed in adults and in infants indicate that some strains of bifidobacteria are capable of surviving passage through the gastrointestinal tract. Significant differences have been observed between the abilities of different bifidobacteria strains to tolerate acid and bile salts, indicating that survival is an important criterion for the selection of potential probiotic strains.
Ingestion of bifidobacteria can improve gastrointestinal transit.
Furthermore, indirect evidence in humans demonstrates that consuming milk fermented by bifidobacteria can lead to reduced levels of certain faecal enzymes such as β-D galactosidase implicated in the conversion of procarcinogens to carcinogens (Bouhnik Y. et at, Eur. J. Clin. Nutr. 1996;50:269–273). Faecal-borne putrefaction metabolities such as p-cresol, indole and ammonia were also reduced when subjects consumed milk fermented by Bifidobacrerium longum and S. thermophilus (Takiguchi, R. et al. Bifidus—Flores, Fructus et Semina 1996;9:135–140).
Antimicrobial activity has been reported to be associated with bifidobacteria . Also, bifidobacteria have been shown to modulate various parameters of the immune system.
Mucosal inflammation in IL-10 deficient mice has been reported to be reduced by feeding the subject animals a preparation of lactic acid bacteria (Madsen, K. et al., Gastroenterol. 1997; 112:A1030.). Further studies completed in rats have demonstrated that ingestion of bifidobacteria can suppress aberrant crypt foci (early preneoplastic lesions) formation in the colon (Kulkarni, N. and Reddy, B. Proc. Soc. Experim. Biol. Med. 1994; 207; 278–283.) in addition to significant decreases in colon tumor incidence and in the numbers of tumors present (Singh, J. et al Carcinogenesis 1997; 18:833–841).
There is an on-going search for probiotic strains with particular beneficial effects on nutrition and therapy and on health generally.
Statements of Invention
The invention provides a strain of Bifidobacterium isolated from resected and washed human gastrointestinal tract which is significantly immunomodulatory following oral consumption in humans.
The strain of Bifidobacterium preferably effects changes in an immunological marker when introduced into a system comprising cells which interact with the immune system and cells of the immune system. Preferably the cells which interact with the immune system are epithelial cells. Preferably the immunological marker is a cytokine, especially TNFα.
In a preferred embodiment the cells which interact with the immune system and the immune system cells are of matched origin.
The cells which interact with the immune system are of gastrointestinal, respiratory or genitourinary origin.
The cells of the immune system are preferably of gastrointestinal, respiratory or genitourinary origin. The invention also provides a strain of Bifidobacterium longum infantis isolated from resected and washed human gastrointestinal tract which is significantly immunomodulatory following oral consumption in humans.
The strain of Bifidobacterium which has significant anti-inflammatory effect following oral consumption in humans.
The strain of Bifidobacterium is preferably isolated from resected and washed human gastrointestinal tract which is capable of combating the effects of inflammatory bowel disease, said capability being maintained in the presence of physiological concentrations of human bile and human gastric juice. The capability of combating the effects of inflammatory bowel disease is measured by measuring a reversal of a wasting disease induced in severe combined immunodeficient recipient mice (SCID) which have been administered purified CD4 + , CD45RB high T cells.
The capability of the strain of Bifidobacterium longum infantis to combat the effects of inflammatory bowel disease can also be measured by measuring the reduction in colonic inflammation in IL-10 deficient mice (IL-10 + 129 Svex strain) following administration of one or more of the strains of Bifidobacterium longum infantis according to the invention alone or in combination with a strain of Lactobacillus salivarius as hereinafter defined.
Interleukin 10 (IL-10) is an important regulatory cytokine that supresses effector functions of macrophage/monocytes, T helper 1 (Th1) cells, and natural killer cells. In addition, IL-10 augments proliferation and differentiation of B cells. Murine models lacking the IL-10 gene spontaneously develop inflammatory bowel disease and gastrointestinal tumors. The gastrointestinal flora have been implicated in the pathogenesis of these disease states as germ free animals do not develop disease.
The strain of Bifidobacterium preferably has inhibitory activity against a broad range of Gram positive and Gram negative bacteria.
Preferably the strain of Bifidobacterium exhibits a broad-spectrum of activity against bacteria including Staphylococcus, Pseudomonas, Coliform and Bacillus species.
In a particular aspect the invention provides strain of Bifidobacterium longum infanis UCC35624 or mutant or variant thereof.
A deposit of Bifidobacterium longum infantis strain UCC 35624 was made at the National Collections of Industrial and Marine Bacteria Limited (NCIMB) at Ferguson Building, Craibstone Estate, Bucksburn, Aberdeen AB21 9YA, UK Jan. 13, 1999 and accorded the accession number NCIMB 41003.
In one embodiment the mutant is a genetically modified mutant.
In one embodiment the variant is a naturally occurring variant of Bifidobacterium longum infantis UCC35624.
The strain of Bifidobacterium may be in the form of viable cells. Alternatively the strain of Bifidobacterium is in the form of non-viable cells.
The invention also provides an antimicrobial agent obtained from a strain of Bifidobacterium of the invention which is antagonistic to the growth of other organisms.
In a further aspect the invention provides a formulation which comprises a strain of Bifidobacterium of the invention.
The formulation may comprise two or more strains of Bifidobacterium.
The formulation may include another probiotic material. Alternatively or additionally the formulation includes a prebiotic material.
The formulation may which include a strain of Lactobacillus salivarius.
The strain of Lactobacillus salivarius may be in the form of viable cells or in the form of non-viable cells.
The Lactobacillus salivarius is preferably isolated from resected and washed human gastrointestinal tract, the Lactobacillus salivarius being significantly immunomodulatory following oral consumption in humans. Preferably the strain of Lactobacillus salivarius is isolated from resected and washed human gastrointestinal tract which inhibits a broad range of Gram positive and Gram negative micro-organisms.
In a preferred embodiment the strain of Lactobacillus salivarius secretes a product having antimicrobial activity into a cell—free supernatant, said activity being produced only by growing cells and being destroyed by proteinase K and pronase E, the inhibitory properties of said strain and its secretory products being maintained in the presence of physiological concentration of human bile and human gastric juice.
Such strains of Lactobacillus salivarius are disclosed in WO 98/35014.
Ideally the strain of Lactobacillus salivarius is Lactobacillus salivarius strain UCC 118 or a mutant or variant thereof. The mutant is a genetically modified mutant.
The variant may be a naturally occurring variant of Lactobacillus salivarius.
A deposit of Lactobacillus salivarius strain UCC 118 was made at the National Collections of Industrial and Marine Bacteria Limited (NCIMB) at Ferguson Building, Craibstone Estate, Bucksbum, Aberdeen AB21 9YA, UK on Nov. 27, 1996 and accorded the accession number NCIMB 40829.
Preferably the formulation includes an ingestable carrier. The ingestable carrier may be a pharmaceutically acceptable carrier such as a capsule, tablet or powder.
The ingestable carrier may be a food product such as acidified milk, yogurt, frozen yoghurt, milk powder, milk concentrate, cheese spreads, dressings or beverages.
The formulation may comprise a protein and/or peptide, in particular proteins and/or peptides that are rich in glutamine/glutamate, a lipid, a carbohydrate, a vitamin, mineral and/or trace element.
In one embodiment the Bifidobacterium is present at more than 10 6 cfu per gram of delivery system.
In another embodiment the formulation includes an adjuvant.
The formulation may include a bacterial component. The formulation may alternatively or additionally include a drug entity. The formulation may also include a biological compound.
The formulation may be in a form for oral immunisation.
The invention further provides a strain of Bifidobacterium or a formulation thereof for use in foodstuffs.
In another aspect the invention provides a strain of Bifidobacterium or a formulation thereof for use as a medicament.
The strain or formulation may be for use in the prophylaxis and/or treatment of undesirable inflammatory activity.
The strain or formulation may be for use in the prophylaxis and/or treatment of undesirable gastrointestinal inflammatory activity such as inflammatory bowel disease eg. Crohns disease or ulcerative colitis, irritable bowel syndrome, pouchitis or post infection colitis.
The undesirable inflammatory activity may be due to cancer.
In addition the strain or formulation may be for use in the prophylaxis and/or treatment of gastrointestinal cancer(s).
The strain or formulation may be used for the prophylaxis of cancer. Further, the strain or formulation may be for use in the prophylaxis and/or treatment of systemic disease such as rheumatoid arthritis.
The strain or formulation may be for use in the prophylaxis and/or treatment of autoimmune disorders due to undesirable inflammatory activity.
The strain or formulation may be for use in the prophylaxis and/or treatment of cancer due to undesirable inflammatory activity.
The strain or formulation may be for use in the prophylaxis and/or treatment of diarrhoeal disease due undesirable inflammatory activity, such as Costidium difficile associated diarrhoea, Rotavirus associated diarrhoea or post infective diarrhoea.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a graph of cfu/ml versus time for Bifidobacterium longum infantis strain 35612 as described in Example 2;
FIG. 2 is a graph of cfu/ml versus time for Bifidobacterium longum infantis strain 35624 as described in Example 2;
FIG. 3 is a graph of percentage weight change versus time (days) for five SCID mice (1–5) administered strain UCC 35624 as described in Example 5;
FIG. 4 is a graph of average percentage weight change versus time (days) for the SCID mice (1–5) administered strain UCC 35624 as described in Example 5;
FIG. 5 is a graph of percentage weight change versus time (days) for mice (6–10) administered a combination of strains Lactobacillus salivarius UCC 118 and UCC 35624 as described in Example 5;
FIG. 6 is a graph of average percentage weight change versus time (days) for mice (6–10) administered a combination of strains UCC 118 and UCC 35624 as described in Example 5;
FIG. 7 is a graph of percentage weight change versus time (days) for mice (11–15) administered a combination of strains UCC 118 and UCC 35624 as described in Example 5;
FIG. 8 is a graph of average percentage weight change versus time (days) for mice (11–15) administered a combination of strains UCC 118 and UCC 35624 as described in Example 5;
FIG. 9 is a bar chart of TNFα levels in patient and control samples in the presence of PBMCs and Bifidobacteria longum infantis as described in Example 7;
FIG. 10 is a bar chart showing TNFα and IL-8 levels in co-cultures of epithelial cells, PBMCs and Bifidobacterium longum infantis as described in Example 7. Controls represent co-cultures of epithelial cells and PBMCs alone;
FIG. 11 are bar charts of peripheral blood cytokine levels following consumption of Bifidobacerium longum infantis by healthy human volunteers (n=18) for three weeks as described in Example 8;
FIG. 12 are bar charts of serum levels of TNFα and IL-LRA following consumption of Bifidobacterium longum infantis to healthy human volunteers (n=18) as described in Example 8;
FIG. 13 is a bar chart of TNFα levels in cell-free spent culture supernatant of Bifidobacterium longum infantis and an MRS control as described in Example 9;
FIG. 14 is a diagrammatic representation of a SCID mouse lower intestine after treatment with Bifidobacterium longum infantis ; and
FIG. 15 is a diagrammatic representation of the lower intestine of an untreated SCID mouse.
DETAILED DESCRIPTION
We have isolated strains of probiotic bacteria which are capable of beneficially modifying and consequently alleviating observable symptoms in inflammatory disorders. These strains and the formulations prepared may be used in a variety of foodstuffs and medicaments to combat the effect of inflammatory disorders.
In vivo and in vitro studies were carried out using the probiotic bacteria strains. It was found that humans fed with yoghurt containing Bifidobacterium longum infantis UCC35624 show marked decreases in their systemic levels of IL-8. This strain may therefore have potential application in the treatment of a range of inflammatory disorders, particularly if used in combination with current anti-inflammatory therapies, such as non-steroid anti-inflammatory drugs (NSAIDs) or Infliximab.
The consumption of Bifidobacterium longum infantis by SCID mice was also examined. While this experiment significantly attenuated inflammatory activity, mice consuming Bifidobacterium longum infantis retained solid stools while control mice suffered from diarrhoea. This anti-diarrhoeal effect could be related to the anti-inflammatory activity of this invention, possibly mediated via cAMP modulation.
It is unknown whether intact bacteria are required to exert an anti-inflammatory effect or if individual active components of the invention can be utilised alone. Proinflammatory components of certain bacterial strains have been identified. The proinflammatory effects of gram-negative bacteria are mediated by lipopolysaccharide (LPS). LPS alone induces a proinflammatory network, partially due to LPS binding to the CD14 receptor on monocytes. It is assumed that components of probiotic bacteria possess anti-inflammatory activity, due to the effects of the whole cell. Upon isolation of these components, pharmaceutical grade manipulation is anticipated.
The general use of Bifidobacterium longum infantis UCC35624 is in the form of viable cells. However, it can also be extended to non-viable cells such as killed cultures or compositions containing beneficial factors expressed by Bifidobacterium longum infantis UCC35624. This could include thermally killed micro-organisms or microorganisms killed by exposure to altered pH or subjection to pressure. With non-viable cells product preparation is simpler, cells may be incorporated easily into pharmaceuticals and storage requirements are much less limited than viable cells. Lactobacillus casei YIT 9018 offers an example of the effective use of heat killed cells as a method for the treatment and/or prevention of tumour growth as described in U.S. Pat. No. 4,347,240.
The invention will be more clearly understood from the following Examples.
EXAMPLE 1
Isolation of Probiotic Bacteria
Appendices and sections of the large and small intestine of the human G.I.T., obtained during reconstructive surgery, were screened for probiotic bacterial strains as shown in Table 1.
TABLE 1
Gastrointestinal tract tissue samples screened for the
presence of probiotic bacteria
Sample
Location
A
Ileum
B
Colon
C
Ileal-caecal region
D
Appendix
E
Appendix
F
Ileum
G
Ileal-caecal region
All samples were stored immediately after surgery at −80° C. in sterile containers. Frozen tissues were thawed, weighed and placed in cysteinated (0.05%) one quarter strength Ringers' solution. Each sample was gently shaken to remove loosely adhering microorganisms (termed—wash ‘W’). Following transfer to a second volume of Ringers' solution, the sample was vortexed for 7 min to remove tightly adhering bacteria (termed—Sample ‘S’). In order to isolate tissue embedded bacteria, samples A, B and C were also homogenised in a Braun blender (termed—homogenate ‘H’). The solutions were serially diluted (dilution 10 −1 from a wash sample was labelled W1, dilution 10 −2 was labelled W2 and the same labelling system was used for the ‘S’ and ‘H’ samples) and spread-plated (100 μl) on to the following agar media: RCM (reinforced clostridial media) and RCM adjusted to pH 5.5 using acetic acid; TPY (typticase, peptone and yeast extract), Chevalier, P. et al., (1990) J. Appl. Bacteriol 68, 619–624). MRS (deMann, Rogosa and Sharpe); ROG (acetate medium (SL) of Rogosa); LLA (Liver-lactose agar of Lapiere); BHI (brain heart infusion agar); LBS ( Lactobacillus selective agar) and TSAYE (tryptone soya agar supplemented with 0.6% yeast extract). All agar media was supplied by Oxoid Chemicals with the exception of TPY agar. Plates were incubated in anaerobic jars (BBL, Oxoid) using CO 2 generating kits (Anaerocult A, Merck) for 2–5 days at 37° C.
Gram positive, catalase negative rod-shaped or bifurcated/pleomorphic bacteria isolates were streaked for purity on to complex non-selective media (TPY). Isolates were routinely cultivated in TPY medium unless otherwise stated at 37° C. under anaerobic conditions. Presumptive Bifidobacteria species were stocked in 40% glycerol and stored at −20° and −80° C.
Fermentation End-Product Analysis
Metabolism of the carbohydrate glucose and the subsequent organic acid end-products were examined using an LKB Bromma, Aminex HPX-87H High Performance Liquid Chromatography (HPLC) column. The column was maintained at 60° C. with a flow rate of 0.6 ml/min (constant pressure). The HPLC buffer used was 0.01 N H 2 SO 4 . Prior to analysis, the column was calibrated using 10 mM citrate, 10 mM glucose, 20 mM lactate and 10 mM acetate as standards. Cultures were propagated in modified MRS broth for 1–2 days at 37° C. anaerobically. Following centrifugation for 10 min at 14,000 g, the supernatant was diluted 1:5 with HPLC buffer and 200 μl was analysed in the HPLC. All supernatants were analysed in duplicate.
Biochemical and Physiological Characterisation
Biochemical and physiological traits of the bacterial isolates were determined to aid identification. Nitrate reduction, indole formation and expression of β-galactosidase activity were assayed. Growth at both 15° C. and 45° C. and protease activity on gelatin were determined. Growth characteristics of the strains in litmus milk were also assessed.
Antibiotic Sensitivity Profiles
Antibiotic sensitivity profiles of the isolates were determined using the ‘disc susceptibility’ assay. Cultures were grown up in the appropriate broth medium for 24–48 h, spread-plated (100 μl) onto agar media and discs containing known concentrations of the antibiotics were placed onto the agar. Strains were examined for antibiotic sensitivity after 1–2 days incubation at 37° C. under anaerobic conditions. Strains were considered sensitive if zones of inhibition of 1 nm or greater were seen.
Isolation of Bifidobacteria sp.
Seven tissue sections taken from the human G.I.T. were screened for the presence of strains belonging to the Bifidobacterium genus. There was some variation between tissue samples as follows. Samples A (ileum) and E (appendix) had the lowest counts with approximately 10 2 cells isolated per gram of tissue. In comparison, greater than 10 3 cfu/g tissue were recovered from the other samples. Similar numbers of bacteria were isolated during the ‘wash’ and ‘sample’ steps with slightly higher counts in the ‘sample’ solutions of F (ileum) and G (ileal-caecal). Of those screened for tightly-adhering bacteria (homogenised), C (ileal-caecal) was the only tissue section that gave significant counts.
During the screening of some tissue sections, for example C and B, there was not a direct correlation between counts obtained during a dilution series. This would indicate that some growth factors, either blood or tissue derived were being provided for the growth of the fastidious bacteria in the initial suspension which was subsequently diluted out.
Strain Selection and Characterisation
Approximately fifteen hundred catalase negative bacterial isolates from different samples were chosen and characterised in terms of their Gram reaction, cell size and morphology, growth at 15° C. and 45° C. and fermentation end-products from glucose. Greater than sixty percent of the isolates tested were Gram positive, homofermentative cocci arranged either in tetrads, chains or bunches. Eighteen percent of the isolates were Gram negative rods and heterofermentative coccobacilli.
The remaining isolates (twenty-two percent) were predominantly homofermentative coccobacilli. Thirty eight strains were characterised in more detail-13 isolates from G; 4 from F; 8 from D; 9 from C; 3 from B and 1 from E. All thirty eight isolates tested negative both for nitrate reduction and production of indole from tryptophan.
Antibiotic Sensitivity Profiles
Antibiotics of human clinical importance were used to ascertain the sensitivity profiles of selected bifidobacteria . The bifidobacteria tested were sensitive to ampicillin, amoxycillin ceftaxime, ceftriaxone, ciprofloxacin, cephradine, rifampicin, amikacin, gentamicin and chloramphenicol. They were also resistant to netilmicin, trimethoprim, nalidixic acid, cefiroxime, vancomycin and tetracycline.
EXAMPLE 2
Acid Resistance
The first line of host defence that a micro-organism reaches following human consumption is gastric acid in the stomach. A key factor influencing bacteria is survival in gastric juice. The survival and growth of Bifidobacterium longum infantis strains 35612 and 35624 in a low pH environment were examined. The strains were routinely cultured in trypticase-peptone-yeast extract (TPY) medium at 37° C. under strict anaerobic conditions (BBL Gas jars using the Merck Anaerocult A gas pak system) for 12–24 h. Human gastric juice was obtained from healthy subjects by aspiration through a nasogastric tube (Mercy Hospital, Cork, Ireland). It was immediately centrigued at 13,000 g for 30 min. to remove all solid particles, sterilised through 0.45 μm filters and 0.2 μm filters and stored at 4° C. The pH and pepsin activity were measured prior to experimental use. Pepsin activity was measured using the quantitative haemoglobin assay (Guantam, S. and R. S. de la Motte. 1989. Proteolytic enzymes, a practical approach. Chapter 3. R. J. Beynon and J. S. Bond (eds.), IRL Press, Oxford University Press; Dawson, R. M. 1969. pH and buffers. In Data for Biochemical Research p 138. R. M. Dawson, D. C. Elliot and K. M. Jones (eds.), Clarendon Press, Oxford). Survival of the strains at low pH in vitro was investigated using the following assays:
(a) Cells were harvested from fresh overnight cultures, washed twice in phosphate buffer (pH 6.5) and resuspended in MRS broth adjusted to pH 3.5, 3.0, 2.5 and 2.0 (with 1N HCl) to a final concentration of approximately 10 6 cfu/ml. Cells were incubated at 37° C. and survival measured at intervals of 5, 30, 60 and 120 min. using the plate count method.
The strains survived with no loss of viability at pH 3.5. At pH 2.5 there was a 3 log reduction over the 60 min. incubation period as depicted in FIGS. 1 and 2 .
Survival of Strains of Bifidobacterium in Human Gastric Juice
Fresh overnight cultures were harvested, washed twice in buffer (pH 6.5) and resuspended in human gastric juice to a final concentration of 10 6 cfu/ml. Survival was monitored over a 30–60 min incubation period at 37° C. The experiment was performed using gastric juice at pH 1.2 (unadjusted) and pH 2.0 and 2.5 (adjusted using 1N NaOH).
Survival of the strains was increased in gastric juice at pH 2.0, when compared with gastric juice at pH 1.2. After 30 min incubation no viable cells were recovered at either pH as shown in Table 2.
TABLE 2
Survival of Bifidobacterium sp. in human gastric juice*
TIME (min)
STRAIN
pH
0
5
30
60
35612
1.2
7.56
0.00
0.00
0.00
2.0
6.27
6.31
2.88
0.00
35624
1.2
5.96
4.18
0.00
0.00
2.0
6.33
6.32
0.00
0.00
35652
1.2
6.16
3.78
0.00
0.00
2.0
8.45
8.40
3.45
0.00
35648
1.2
6.00
0.00
0.00
0.00
2.0
7.89
6.45
0.00
0.00
35687
1.2
6.68
0.00
0.00
0.00
2.0
8.75
8.77
3.34
0.00
BO
2.0
8.41
8.56
8.42
8.43
10
2.0
8.39
8.56
4.64
0.00
6.3
2.0
8.75
8.75
8.29
8.42
B. longum
6
2.0
8.15
8.02
0.00
0.00
*survival expressed as log 10 cfu/ml
EXAMPLE 3
Bile Resistance
In the evaluation of the effectiveness of using lactic acid bacteria as beneficial members of the gastrointestinal tract, it is considered that resistance to bile acids is an important biological strain characteristic required for survival in this hostile environment and in addition they must not impinge on the health of the host by producing toxic compounds such as deoxycholic (DCA) and lithocholic acid (LCA) which have been implicated in a number of cytotoxic phenomena.
A number of Bifidobacterium longum infantis strains were streaked onto TPY agar plates supplemented with porcine bile (B-8631, Sigma Chemical Co. ltd., Poole) at concentrations of 0.3, 0.5, 1.0, 1.5, 5.0 and 7.5% (w/v) (Legrand-Defretin, R. et al., Lipids 1991; 26 (8), 578–583). Porcine bile is the closest in composition to human bile with respect to bile salt/cholesterol and phospholipid/cholesterol ratios. Plates were incubated at 37° C. under anaerobic conditions and growth was recorded after 24–48 h. Strain 35624 was found to be strongly bile resistant and grew to confluence at up to 55 porcine bile as shown in Table 3.
TABLE 3
Growth of Bifidobacterium sp. isolates in the presence of
porcine bile
% (w/v) PORCINE BILE
STRAIN
0.0
0.3
0.5
1.0
1.5
5.0
7.5
34612
+
−
−
−
−
−
−
35624
+
+
+
+
+
+
−
35652
+
−
−
−
−
−
−
35658
+
+
+
+
−
−
−
35687
+
−
−
−
−
−
−
−, no growth;
+, confluent growth
Human bile was obtained from several human gall bladders and sterilised at 80° C. for 10 min. The bile acid composition of human bile was determined using reverse phase High Performance Liquid Chromatography (HPLC) in combination with a pulsed amperometric detector according to the method of Dekker, R. R. et al., Chromatogaphia, 1991, 31 (11/12), 255–256. Human bile was added at a concentration of 0.3% (v/v). Freshly streaked cultures were examined for growth after 24 and 48 h.
Strain 35624 was capable of growth in the presence of physiologically relevant human bile (0.3% (v/v)).
Growth of the strains was examined in the presence of individual conjugated and deconjugated bile acids. Under physiological conditions bile acids are often found as sodium salts. The strains were screened for growth on TPY agar containing the conjugated and deconjugated sodium salts of each of the following bile acids.
(a) conjugated form: glycocholic acid (GCA); glycodeoxycholic acid (GDCA); and glycochenodeoxycholic acid (GCDCA);
(b) deconjugated form: lithocholic acid (LCA); chenodeoxycholic acid (CDCA); deoxycholic acid (DCA) and cholic acid (CA). For each bile acid concentrations of 1, 3 and 4 mM were used. Growth was recorded after 24 and 48 h anaerobic incubation.
The five strains studied grew on agar medium supplemented with 5 mM GCA and GCDCA and on agar medium supplemented with 1 mM GDCA as shown in Table 4. Strain 35624 was resistant to concentrations of 5 mM LCA (data not shown) and strains 35612 and 35624 were capable of growth at concentrations of 5 mM CA as shown in Table 5. No growth was observed in the presence of 1 mM CDCA (data not shown).
TABLE 4
Growth of Bifidobacterium sp. isolates in the presence
of glycine-conjugated bile acids
BILE ACIDS (mM)
GCDCA
GDCA
GCA
STRAIN
0
1
3
5
0
1
3
5
0
1
3
5
35612
+
+
+
+
+
+
+
+
+
+
+
+
35624
+
+
+
+
+
+
+
+
+
+
+
+
35652
+
+
+
+
+
+
+
+
+
+
+
+
35658
+
+
+
+
+
+
+
+
+
+
+
+
35687
+
+
+
+
+
+
+
+
+
+
+
+
−, no growth;
+, confluent growth
GCDCA, glycochenodeoxycholic acid;
GDCA, glycodeoxycholic acid;
CGA, glycocholic acid.
TABLE 5
Growth of Bifidobacterium sp. isolates in the presence of
unconjugated cholic acid (CA)
CHOLIC ACID (mM)
STRAIN
0
1
3
5
35612
+
+
+
+
35624
+
+
+
+
35652
+
+
−
−
35658
+
+
−
−
35687
+
+
−
−
−, no growth;
+, confluent growth
EXAMPLE 4
Antimicrobial Activity
Bifidobacterium species exert inhibitory effects on other bacteria by excluding long term colonisation by invasive pathogens. Their antagonistic activity is due to the production of acetic and lactic acid though fermentation (Scardovi, V. (1986) Bifidobacterium in Bergey's Manual of systemic bacteriology, Vol. 2. Eds. Sheath, P. H., Main, N. S., Sharpe, M. and Holdt, J. G., Williams and Wilkins Publishers, Baltimore M.D., p1418). Very few reports exist on the production of antimicrobial compounds other than acids (Anand, S. K. et al. Cult. Dairy Prods. 1985; J. 2, 21–23). Bacteriocins and other compounds may influence the survival of a bacterium in an ecological niche and allow them to effectively dominate fermenting ecosystems. Such a feature is a good trait for a probiotic strain.
The inhibitory spectra of various bifidobacterial strains was determined by the method of Tagg et al. (Tagg. J. R. et al. Bacteriol. Rev. 1976; 40, 722–756). Cell free supernatant was assayed for inhibitory activity against a wide range of Gram positive and Gram negative micro-organisms. Overlays of each indicator were prepared on agar plates and allowed to dry. Spots (5 ml) of cell free supernatant were placed on the seeded plates, allowed to dry and the plates were incubated overnight.
It was observed that the strains were inhibitory to a wide range of Stapbylococcus, Pseudomonas, Coliform and Bacillus sp. when testes on TPY medium. Zones of inhibition of up to 4.4 mm were recorded against Pseudomonas and Staphylococcus and up to 7.0 mm surrounding Bacillus sp. as shown in Tables 6 and 7. However, when the deferred assays were performed on buffered TPY medium zones of inhibition were not observed against any indicator strain. Therefore, inhibition appeared to be solely due to the presence of acid produced by the bifidobacteria .
TABLE 6
Inhibition of Staphylococcus strains by Bifidobacterium sp. on
unbuffered medium*
B. longum 1
B. longum 9
B. longum 10
63
35612
35624
35652
35658
35675
35678
35687
S. aureus MHS
1.5
2
1.5
3.5
1.5
1
2
2
1
2.5
1.5
S. aureus HC
1.5
1.5
2
2.5
2
1.5
2.5
2
1.5
1.5
2
S. aureus 771
1.5
3
1.5
3
2
2
2.5
2
3
2
3.5
S. aureus 949
2
3.5
2.5
2
3
3.5
3
2.5
3.5
3.5
2.5
S. aureus 1018
1
3.5
1.5
1.5
2
3.5
1
3
3.5
2.5
2
S. aureus 1502
1.5
3.5
1
2
2.5
2.5
1.5
3
4
2.5
1.5
S. aureus 1505
3
4
3
2.5
2.5
3
2.5
4.5
5.5
5
5.5
S. aureus 1511
1
3.5
2
1.5
2
2.5
3
3.5
4
2.5
3
S. aureus 1522
1.5
3
2.5
1
2.5
1.5
2.5
2.5
3.5
3.5
3
S. aureus 1499
1.5
3.5
1.5
1.5
2
2
3
2
3.5
3.5
1.5
S. aureus 1963
2
3
2
2.5
3.5
3.5
3.5
3.5
2.5
3
2.5
S. aureus PRMM
1
3.5
1
1.5
1
3.5
2
2
3
2
2.5
S. albus
1
2
1.5
1
2
2.5
2
1.5
2
1.5
1
S. carnosus
1
1.5
2
2.5
2.5
2.5
2
2.5
2
1.5
1
*values given are radii of inhibition zones in mm (distance from edge of producer colony to the edge of zone of inhibition)
TABLE 7
Inhibition of Pseudomonas and Bacillus strains by Bifidobacterium sp.
on unbuffered medium*
B. longum 1
B. longum 9
B. longum 10
63
35612
35624
35652
35658
35675
35678
35687
P. fluorescens HC.
1
2.5
1.5
1
1.5
2
3
2
1.5
2
2.5
P. fluorescens MHP
1.5
4.5
3.5
2
2.5
3.5
2.5
2.5
3.5
2
4
P. fluorescens DW
1.5
4
4
3.5
2.5
3.5
2.5
4.5
5.5
3.5
5
B. cereus
3
3
5
3
4
4
3.5
5
6
4.5
5.5
B. subtilis
2
2.5
5
2
3
6
3
6
7
3
6
B. circulans
1
2
4
1.5
2.5
1.5
2
3.5
4.5
2
4.5
B. thuringensis
2.5
3.5
5
3
3.5
4.5
4
5.5
6.5
4.5
5.5
*values given are radii of inhibition zones in mm (distance from edge of producer colony to the edge of zone of inhibition)
EXAMPLE 5
Murine Feeding Trial to Investigate the Ability of Lactobacillus salivarius subsp. Salivarius UCC 118 and Bifidobacteria longum infantis 35624 to Alleviate the Symptoms of Inflammatory Bowel Disease (IBD)
Background
A number of mouse models have recently been generated by either genetic or immunological means to study the mechanisms of IBD. One of these models involves the transfer of spleen or lymph node-derived CD4 + T lymphocytes from normal mice into severe combined immunodeficient recipient mice (SCID). It has been demonstrated that mice who receive purified CD4 + , CD45RB high T cells develop a wasting disease characterised by chronic intestinal inflammation which is more severe in the colon. In this study a control group of SCID mice was injected with CD4 + CD45RB high and the mice developed a progressive wasting disease including hunched over appearance, piloerection of the coat, diarrhoea, weight loss and macro and microscopic colon damage. A feeding trail was set up administering UCC 118 and strain 35624 (also referred to herein as UCC 35624) to determine if the symptoms of IBD could be modified in this model.
Bacterial Strains
Lactobacillus salivarius subsp. Salivarius UCC 118 and Bifidobacterium longum infantis UCC 35624 were isolated from the ileal-caecal region of an adult human as described in Example 1. In this example, spontaneous rifampicin and streptomycin resistant derivatives of the strains were generated by plating cells, previously grown overnight and subsequently washed in quarter strength Ringer's solution on MRS and TPY agar containing 50 μg/ml rifampicin (Sigma) respectively and MRS containing 400 μg/ml streptomycin (Sigma). Plates were incubated for 2 days at 37° C. anaerobically. The resulting antibiotic resistant derivatives were determined to be otherwise phenotypically similar to the parent strain. This selectable trait enabled the strains to be readily enumerated following gut transit.
Animals and Maintenance
Donor mice (C57BL/6×BALB/c) F1 were purchased from Simosen Laboratories (Gilroy, Calif.) and maintained at the University of California—Los Angeles vivarium in ventilated cage racks (Thoren caging systems, Hazelton, Pa.) under specific pathogen free (SPF) conditions. CB-17 SCID mice were bred in ventilated cage racks originally obtained from the University of California—Los Angeles SCID core facility. The nice were reduced flora (RF) mice rather than germ free and acting as the recipient mice (Aranda R. et al. J. of Immunol. 1997; 158(7), 3464–3473).
Eight week old, female CB-17 (SCID) mice were housed in pairs in filter top cages in ventilated racks. The mice were divided into four groups Group A: consumed 10% skim milk, control; Group B: consumed Lactobacillus salivarius UCC 118, Group C: consumed Lactobacillus salivarius UCC 118 and Bifidobacterium longum UCC 35624 9 (1:1 ratio); Group D: consumed Bifidobacterium longum UCC 35624. UCC 118 and UCC 35624 which were grown overnight in MRS broth and MRS broth supplemented with 0.05% cysteine (Sigma) respectively, were washed in PBS, resuspended in skim milk (10% (v/v)) and administered in the otherwise sterile drinking water (PBS). The mice in each respective group received 2.55×10 8 cfu/ml of UCC 118 and 2.35×10 8 cfu/ml of UCC 35624 daily for the duration of the feeding period. Control mice received sterile milk diluted in sterile phosphate buffered saline (PBS) and were maintained under identical conditions as the test group.
Experimental Design
All CB-17-mice were administered their respective feed according to their grouping for 2 days prior to injection with the CD4 + CD45RB high cells. The sorted donor lymphocytes (3–4×10 5 ) were represented in 200 μl of sterile PBS and injected i.p. into the recipient CB-17 SCID mice. All mice were weighed initially, then twice weekly thereafter. They were observed for clinical signs of illness: hunched over appearance, piloerection of the coat and diarrhoea.
Evaluation of the Effects of the Administered Probiotics on the Numbers of Indigenous Bacteria Culturable from Mouse Faeces.
The influence exerted by the administered UCC 118 and UCC 35624 when either administered alone or in combination with each other, on the microflora of the CB-17 SCID murine gut was investigated. Faecal samples were collected from each mouse weekly, weighed and resuspended in 10 ml PBS. The samples were then serially diluted in PBS and either pour plated or spread plated in appropriate dilutions on appropriate media in duplicate. The following bacterial groups were enumerated: lactobacilli; bifidobacteria; enterococci ; bacteroides and coliforms. The selective media used were; de Mann Rogosa & Sharpe (S) agar; MRS agar supplemented with 0.2% lithium chloride (BDH), 0.3% sodium propionate (Fluke chemie), 0.5% cysteine hydrochloride (Sigma), and 5% sheep's blood; Slanetz and Bartley agar; Wilkins and Chalgren agar supplemented with anaerobic supplement SR 108 and 5% horse blood; and Violet Red Bile Agar. (All Oxoid unless otherwise stated). VRBA and Slanetz and Bartley plates were incubated aerobically for 24 and 45 h respectively. All other plates were incubated anaerobically for 48 h at 37° C.
Enumeration of Culturable Indigenous Flora from Specific Segments of the CB. 17 SCID Murine G.I.T.
After the feeding period all mice were sacrificed and dissected. Segments of the ileal-caecal region, small intestine, and the large intestine were removed. A peripheral lymph node (PLN), mesenteric lymph node (MLN) and a piece of the spleen were also taken. All tissues were weighed before being resuspended in 10 nil of PBS. Samples were then homogenised and serially diluted in PBS and either spread plated or pour plated in appropriate dilutions on appropriate media in duplicate. The bacterial groups were enumerated the same as those enumerated in the faecal analysis and samples were incubated as described previously.
Preparation of Intraepithelial and Lamiinapropria Lymphocytes
The isolation of the mucosal lymphocytes was carried out according to the method of Aranda, R. etal ((1997) supra).
Flow Cytometric Analysis of Lymphocyte Populations.
The analysis was conducted as described by Aranda, R et al. ((1997) supra)
Preparation of Tissue for Histopathological Analysis
Tissue samples were taken from the small intestine, large intestine, and ileal caecal region and fixed in 10% formalin. The procedure was as described in Aranda, R. et al. ((1997) supra).
It was observed from the experiment carried out that, consistent with previous results, the SCID mice reconstituted with CD4 + CD45RB high T lymphocytes and consuming skim milk alone (control) developed a progressive wasting disease, identified by their significant weight loss. Disease became apparent at about 2 and a half to three weeks and the sick mice characteristically manifested a hunched over appearance, piloerection of their coat, and loose stool. One of the mice in the control group (mouse 4) died after 25 days and mice 1, 2, 3 and 5 showed a −20%, 25%, 21% and −35% percentage weight change respectively as depicted in FIGS. 3 and 4 .
CB-17 SCID mice consuming UCC 118 alone gave a similar result as the controls with the characteristic weight loss. Mouse 3 died after 14 days, and mice 4, 5 and 6 showed a −15%, −25% and −28% percentage weight change respectively (data not shown). The mice consuming a combination of UCC 118 and UCC 35624 were found to have a marked improvement on the control mice. These mice did not lose as much weight as the control mice over the feeding period. Even after 35 days three of the mice in this group showed little percentage weight change. ( FIGS. 5 and 6 ). Two of the mice in this group showed a weight loss only after about 30 days whereas control mice showed weight loss at 14 days ( FIGS. 3 and 4 ).
Mice consuming UCC 35624 alone appeared in good health and again weight loss when compared to the controls was considerably less ( FIGS. 7 and 8 ). It can be concluded therefore that consumption of UCC 35624 either alone or in combination with UCC 118 alleviates the symptoms of inflammatory bowel disease.
Table 8 is a summary of experimental data for the study on the treatment of CD45RB colitis induced CB17 and SCID mice with a cocktail of UCC 118 and UCC 35624.
It was found in the studies that the mice were successfully reconstituted with lymphocytes and lymphocytes having been derived from the donor model (data not shown).
TABLE 8
Treatment of CD45RB colitis induced CB 17 SCID mice with a cocktail
of Lactobacillus salivarius UCC 118 and Bifidobacteria .
Mouse 1
Mouse 2
Untreated
Untreated
(RB hi cells +
(RB hi cells +
Mouse 3
Mouse 4
Mouse 5
Mouse 6
skimmed
skimmed
Cocktail
Cocktail
Cocktail
Cocktail
Organ
milk)
milk)
Treated
Treated
Treated
Treated
% weight
31.25
27.74
14.50
14.05
21.88
11.18
loss
Final
looks ill
very ill
very
slightly ill
healthy
healthy
Appearance
healthy
Stool
very mushy
very mushy
mushy
solid
semi solid
semi solid
Appearance
Colon
thickened
very
slightly
slight
slightly
slight
Appearance
thickened
thickened
proximal
thickened
proximal
thickening
thickening
No. SIEL
100,000
200,000
0
0
512,000
28,000
No. LIEL
25,000
72,000
100,000
50,000
384,000
96,000
No. SLPL
200,000
100,000
264,000
200,000
640,000
104,000
No. LLPL
96,000
256,000
160,000
160,000
256,000
160,000
No. MLN
0
N/A
81,900
N/A
28,800
N/A
No. PLN
0
192,000
0
120,000
64,000
0
Spleen #
960,000
512,000
640,000
640,000
512,000
6,400,000
Lymphos.
CD3+/H-2Kb+ Flow correction %
No. SIEL
62,000
114,000
0
0
450,560
17,920
No. LIEL
21,250
48,960
74,800
38,000
345,600
65,280
No. SLPL
74,000
42,000
158,400
136,000
384,000
66,460
No. LLPL
67,200
161,280
115,200
108,000
184,320
108,800
No. MLN
0
N/A
130,00
N/A
64,000
N/A
No. PLN
0
126,720
0
87,600
54,400
0
Spleen
518,400
102,400
211,200
307,200
230,400
4,480,000
UCC 118 bacterial counts (per biopsy) post mortem
SI
0
0
1,200
0
0
0
LI
0
0
>30,000
>30,000
100
11,600
Caecum
0
0
>30,000
>30,000
>30,000
>30,000
Spleen
0
0
0
1,350
0
0
Colon Pathological Scoring
A (0–3)
—
1.0
1.0
2.0
—
—
B (0–2)
—
1.5
1.0
1.0
—
—
C (0–3)
—
2.5
1.0
2.0
—
—
D (0–3)
—
2.0
3.0
3.0
—
—
E (1–3)
—
1.0
1.0
2.0
—
—
Remarks
Total Score
—
8.0
7.0
10.0
—
—
A: Degree of inflammatory infiltrate;
B: Mucin depletion;
C: Epithelia hyperplasia;
D: No. of TEL in the crypts;
E: No. of inflammatory foci per high power fields
EXAMPLE 7
In Vitro Studies to Examine the Immune Perception of Bifidobacterium longum infantis.
Overnight washed cultures of Bifidobacteria were incubated with human peripheral blood mononuclear cells (PBMCs) from both healthy volunteers (n=9) and patients suffering from inflammatory bowel disease (n=5). Production of the proinflammatory cytokine tumour necrosis factor α (TNFα) was measured by ELISA in seventy two hour culture supernatants. Co-incubation of Bifidobacterium longum infantis with human PBMCs did not result in the stimulation of TNFα production ( FIG. 9 ). Thus, exposure of the systemic immune system to this bacterium does induce an inflammatory response.
In order to assess the immune perception of Bifidobacterium longum infantis at mucosal surfaces, co-culturing of epithelial cells and PBMCs was performed in transwell chambers. Briefly, an epithelial cell monolayer was grown in the upper chamber and PBMCs were incubated in the lower compartment. These were seperated from each other by a porous membrane which allowed the passage of soluble mediators between the two compartments but did not allow cell-cell contact. Using this model, the production of TNFα and Interleukin-8 (IL-8) was measured in the presence and absence of Bifidobactertium longum infantis in the PBMC compartment. Co-culture of epithelial cells, PBMCs and Bifidobacterium longum infantis resulted in significant suppression of TNFα and IL-8 production ( FIG. 10 ). Thus, a tri-cellular network involving epithelial cells, PBMCs and Bifidobacterium longum infantis results in suppression of proinflammatory cytokine production.
EXAMPLE 8
In Vivo Anti-Inflammatory activity of Bifidobacterium longum infantis
Bifidobacterium longum infantis (1×10 9 cells per day) was consumed by 18 healthy humans in a fermented milk (yoghurt) product for three weeks. Serum was collected for cytokine analysis pre and post consumption of this probiotic strain. Faecal samples were obtained for microbiological analysis.
Considerable modification of peripheral blood cytokine levels were observed in this feeding study. Serum soluble Interleukin-6 receptor (sIL-6R, p=0.007), Interferon-γ (IFNγ, p=0.041) and IL-8 (p=0.004) levels were significantly reduced following consumption of this probiotic strain ( FIG. 11 ). No alteration in serum TNFα and Interleukin-1 receptor antagonist (IL-1RA) levels were observed ( FIG. 12 ). Bifidobacterium longum infantis was detected at approximately 1×10 5 colony forming units per gram of faecal matter over the course of this feeding study.
Targeted in vitro selection criteria reflecting the complex interactions of the GI environment allow for the identification of probiotic strains capable of functioning effectively when reintroduced into that environment. Using the selection criteria outlined above, the probiotic bacteria Bifidobacterium longum infantis has demonstrable immunomodulating properties in vitro. Following consumption by SCID mice and human volunteers, significant modification of systemic immune parameters was noted. Thus, the use of Bifidobacterium longum infantis as a biotherapeutic agent in the treatment of immune mediated diseases is warranted.
EXAMPLE 9
Measurement of TNFα in Bifidobacterium longum infantis UCC 35624 Cell Free Supernatant
Overnight cultures of Bifidobacterium longum infantis were centrifuged and the cell-free culture supernatant was examined for the presence of cytokine inhibitors. Cell free supernatants were incubated with human TNFα for 20 minutes at 37° C. TNFα levels were quantified thereafter by ELISA. Following exposure to the Bifidobacteria supernatant, TNFα levels were significantly reduced ( FIG. 13 ). Thus, Bifidobactenum longum infantis UCC35624 secretes a factor that antagonises TNFα activity. Production of this factor by Bifidobacterium longum infantis at the surface of the gastrointestinal tract, in vivo, would significantly restrict the host inflammatory response.
This indicates that the antagonism of TNFα also occurs at a molecular level due to a soluble factor released by UCC 35624.
Inflammation
Inflammation is the term used to describe the local accumulation of fluid, plasma proteins and white blood cells at a site that has sustained physical damage, infection or where there is an ongoing immune response. Control of the inflammatory response is exerted on a number of levels (for review see Henderson B., and Wilson M. 1998. In “Bacteria-Cytokine interactions in health and disease. Portland Press, 79–130). The controlling factors include cytolines, hormones (e.g. hydrocortisone), prostaglandins, reactive intermediates and leukotrienes. Cytokines are low molecular weight biologically active proteins that are involved in the generation and control of immunological and inflammatory responses, while also regulating development, tissue repair and haematopoiesis. They provide a means of communication between leukocytes themselves and also with other cell types. Most cytokines are pleiotrophic and express multiple biologically overlapping activities. Cytokine cascades and networks control the inflammatory response rather than the action of a particular cytokine on a particular cell type (Arai K I, et al., Annu Rev Biochem 1990; 59:783–836). Waning of the inflammatory response results in lower concentrations of the appropriate activating signals and other inflammatory mediators leading to the cessation of the inflammatory response. TNFα is a pivotal proinflammatory cytokine as it initiates a cascade of cytokines and biological effects resulting in the inflammatory state. Therefore, agents which inhibit TNFα are currently being used for the treatment of inflammatory diseases, e.g. infliximab.
Pro-inflammatory cytokines are thought to play a major role in the pathogenesis of many inflammatory diseases, including inflammatory bowel disease (IBD). Current therapies for treating IBD are aimed at reducing the levels of these pro-inflammatory cytokines, including IL-8 and TNFα. It has been suggested that such therapies may also play a significant role in the treatment of systemic inflammatory diseases such as rheumatoid arthritis. Humans fed with yoghurt containing Bifidobacterium longum infantis UCC35624 have shown marked decreases in their systemic levels of IL-8. This strain may therefore have potential application in the treatment of a range of inflammatory diseases, particularly if used in combination with current anti-inflammatory therapies, such as non-steroid anti-inflammatory drugs (NSAIDs) or Infliximab.
Diarrhoeal Disease.
The barrier function of the intestinal epithelium can be diminished during nervous (acetylcholine) and immune (histamine) mediated secretion. Certain bacterial toxins may also induce Ca2 + and PKC dependent secretion and thereby can disturb the epithelial barrier (Ganguly N K and Kaur T. Indian J Med Res 1996; 104:28–37, Groot J A. Vet Q 1998; 20(S3):45–9). Several studies have examined the prevention and treatment of diarrhoea using probiotic bacteria. Prospective studies have demonstrated the efficacy of lactic acid bacteria administration for both prophylactic and therapeutic use against diarrhoea in pre-mature infants, new borns, children (Isolauri E, et al., Dig Dis Sci 1994 December; 39(12):2595–600) and in the treatment of antibiotic related diarrhoea (Siitonen S, et al., Ann Med 1990 February; 22(1):57–9) and traveller's diarrhoea (Oksanen P J, et al., Ann Med 1990 February; 22(1):53–6).
We have examined consumption of Bifidobacterium longum infantis UCC 35624 by SCID mice. It was found that inflammatory activity was significantly attenuated and mice consuming Bifidobacterium longum infantis UCC 35624 retained solid stools while control mice suffered from diarrhoea. FIGS. 14 and 15 illustrate the lower intestine of treated and untreated SCID mice. The lower intestine shown includes the caecum 2, intestine 3 and anus 5. In FIG. 14 the mice were treated with Bifidobacterium longum infantis UCC 35624 and it is apparent that solid stools 4 have been retained in the intestine. In comparison FIG. 15 shows the untreated mouse intestine 3, characteristically inflamed. No water absorption has occurred so that no solid stools are retained resulting in diarrhoea.
The anti-diarrhoeal effect observed may be related to the anti-inflammatory activity, possibly mediated via cAMP modulation. Cyclic AMP-dependent Cl-secretion is the major secretory pathway in the human intestine (Brzuszczak I M, et al., J. Gastroenterol. Hepatol. 1996; 11(9):804–10). It can be inferred that the anti-diarrhoeal effect of Bifidobacterium longum infantis UCC 35624 is not restricted just to diarrhoea resulting from gastrointestinal inflammation, but can be applied to the general treatment of diarrhoeal disease.
Autoimmune Disease
The immune system has a large repertoire of specificities expressed by B and T cells. Some of these specificities will be directed to self-components. Self-recognition is normally controlled by clonal deletion and inactivation of self-reactive lymphocytes. However, there is a constant background of autoimmunity with antibodies to many proteins being found in serum. A breakdown in the self-nonself recognition system results in autoimmunity. When autoimmune disease does occur, the resulting immune response damages the tissue bearing the offending antigen. Immune complex deposition, type II hypersensitivity and cell-mediated reactions are the most important mechanisms by which immunopathological damage occurs. Examples of autoimmune diseases include, but are not limited to, systemic lupus erythematosus, rheumatoid arthritis, insulin dependent diabetes mellitus, myasthenia gravis and pernicious anaemia. Bifidobacterium longum infantis and Lactobacillus salivarius subsp. salivarius are immunomodulatory bacteria. Thus, consumption either as single components or in combination of these bacteria by patients suffering from autoimmune disease may restrict organ damage and help restore normal body homeostasis.
Inflammation and Cancer
The production of multifunctional cytokines across a wide spectrum of tumour types suggests that significant inflammatory responses are ongoing in patients with cancer. It is currently unclear what protective effect this response has against the growth and development of tumour cells in vivo. However, these inflammatory responses could adversely affect the tumour bearing host. Complex cytokine interactions are involved in the regulation of cytokine production and cell proliferation within tumour and normal tissues (McGee D W, et al., Immunology 1995 September; 86(1):6–11, Wu S, et al., Gynecol Oncol 1994 April; 53(1):59–63). It has long been recognised that weight loss (cachexia) is the single most common cause of death in patients with cancer (Inagaki J, et al., Cancer 1974 February; 33(2):568–73) and initial malnutrition indicates a poor prognosis (Van Eys J. Nutr Rev 1982 December; 40(12):353–9). For a tumour to grow and spread it must induce the formation of new blood vessels and degrade the extracellular matrix. The inflammatory response may have significant roles to play in the above mechanisms, thus contributing to the decline of the host and progression of the tumour. Due to the anti-inflammatory nature of these bacterial strains, they may reduce the rate of malignant cell transformation. Furthermore, intestinal bacteria can produce, from dietary compounds, substances with genotoxic, carcinogenic and tumour-promoting activity and gut bacteria can activate pro-carcinogens to DNA reactive agents (Rowland I. R. (1995). Toxicology of the colon: role of the intestinal microflora. In: Gibson G. R. (ed). Human colonic bacteria: role in nutrition, physiology and pathology, pp 155–174. Boca Raton CRC Press). In general, species of Bifidobacteria and Lactobacillus have low activities of xenobiotic metabolising enzymes compared to other populations within the gut such as bacteroides, eubacteria and clostridia (Saito Y., et al., Microb. Ecol. Health Dis., 1992; 5, 105–110). Therefore, increasing the number of lactic acid bacteria in the gut could beneficially modify the levels of these enzymes.
Prebiotics
The introduction of probiotic organisms is accomplished by the ingestion of the microorganism in a suitable carrier. It would be advantageous to provide a medium that would promote the growth of these probiotic strains in the large bowel. The addition of one or more oligosaccharides, polysaccharides, or other prebiotics enhances the growth of lactic acid bacteria in the gastrointestinal tract (Gibson, G R. Br. J. Nutr. 1998; 80 (4):S209–12). Prebiotics refers to any non-viable food component that is specifically fermented in the colon by indigenous bacteria thought to be of positive value, e.g. bifidobacteria, lactobacilli . Types of prebiotics may include those which contain fructose, xylose, soya, galactose, glucose and mannose. The combined administration of a probiotic strain with one or more prebiotic compounds may enhance the growth of the administered probiotic in vivo resulting in a more pronounced health benefit, and is termed synbiotic.
Other Active Ingredients
It will be appreciated that the Bifidobacterium may be administered prophylactically or as a method of treatment either on its own or with other probiotic and/or prebiotic materials as described above. In addition, the bacteria may be used as part of a prophylactic or treatment regime using other active materials such as those used for treating inflammation or other disorders, especially those of the gastrointestinal tract. Such combinations may be administered in a single formulation or as separate formulations administered at the same or different times and using the same or different routes of administration.
The invention is not limited to the embodiments hereinbefore described which may be varied in detail. | A strain of Bifidobacterium isolated from resected and washed human gastrointestinal tract is significantly immunomodulatory following oral consumption in humans. The strain is useful in the prophylaxis and/or treatment of undesirable inflammatroy activity, especially gastrointestinal inflammatory activity such as inflammatory bowel disease or irritable bowel syndrome. The inflammatory activity may also be due to cancer. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional Application of prior application Ser. No. 10/881,460, filed Jun. 30, 2004, which claims the benefit of U.S. Provisional Patent Application No. 60/488,582 filed on Jul. 17, 2003. Both Applications are expressly incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
TECHNICAL FIELD
[0003] This invention relates to the fields of electronics devices and computer programming. More particularly, it relates to an electronic estrus detection device that stores data based on external stimuli.
BACKGROUND OF THE INVENTION
[0004] A pervasive problem that plagues animal breeding is determining the optimum time a female should be inseminated. Breeding bovine animals is made easier when an accurate determination can be made as to when a cow should be artificially inseminated. Generally, cows in heat are near ovulation and let themselves be mounted. Accurately determining when a cow is in heat, and hence should be inseminated, is important because of the scarcity of resources necessary to provide a successful insemination, the expense of those materials, and because the opportunity costs of failed inseminations are great. With respect to bovine animals, millions of dollars worth of semen is wasted each year because of unsuccessful inseminations, the vast majority of which were poorly timed.
[0005] Prior attempts have been made to determine when a cow is in heat. In one prior-art method, the animals are simply observed. When mating behavior is observed, a breeder determines whether to act. But such a method is impractical in light of the demands associated with physically observing many animals over long periods of time.
[0006] The SHOWHEAT device made by the IMV International Corporation of Minneapolis, Minn. is an exemplary prior-art device that is designed to help determine when a cow is in heat. But, this device makes an actual timing determination. Rather than providing raw data, which a skilled person could include as a factor in determining whether a certain time is the best time to commence insemination, prior-art devices remove the decision-making process from a breeder. Raw data related to recent animal behavior is not provided.
[0007] To illustrate this mere one shortcoming of the prior art, consider a group of females outfitted with prior-art devices. In situations where multiple prior-art devices simultaneously indicated that many females are ready for insemination, a breeder would be deprived of valuable information indicating which of the animals should be inseminated first. That is, if a herd of cows were gathered after a certain period of time, and multiple cows were flagged as ready for insemination, prior-art devices merely indicate that at some point the specific cows were ready to be inseminated, if such a determination was accurate. This problem is exacerbated when limited insemination equipment is available. Limited time may require deciding which cows to inseminate first, but the prior-art attempts do not provide a way to retrieve this data.
[0008] Another shortcoming of the prior art is the inability to retrieve historical data. This historical data could be used to better understand the mating-behavior events or behavior leading up to ovulation. Without this historical data, a breeder does not have as much information on which to base an insemination decision.
[0009] Still another shortcoming of various prior-art attempts is the recordation of false positives. A false positive erroneously indicates that a mount took place. For example, certain ineloquent males or females who lack the mounting prowess of others may fumble while attempting to mount a female. Thus, while attempting to register what should be considered a single successful mount, prior-art devices may erroneously register multiple mounting attempts as actual mounts.
[0010] Still another shortcoming of the prior art is that the historical devices are physically large, making them difficult to securely attach to the animal, such as bovine animals. Large devices are also difficult to maintain attached to the bovine animal during mounting behavior.
[0011] A final illustrative shortcoming of prior-art devices is the manner in which they provide feedback. Typically, prior-art devices do not provide detailed feedback in such a manner that is easy to observe from a safe or comfortable distance. A dairy farmer may have only a short time frame to read from many devices. Not being able to readily observe indications of mounting behavior or other breeding behavior (especially in its raw format) imposes resource burdens on a breeder.
[0012] There is a need for a method and system that more accurately tracks mating-behavior events and presents data related to those events so as to enable a decision maker to determine an optimum insemination time. The prior art could be improved by a device that provides raw data corresponding to mating-behavior events, thereby enabling a more complete, informed insemination decision to be made. The prior art could also be improved by providing a device that logs historical data related to mating behavior leading up to ovulation and that reduces the occurrence of false positives. The state of the art could be improved by providing a device with a sufficiently narrow footprint and low profile that would make attachment and retention to an animal easier and more reliable. Still further, the state of the art could be improved by providing a device that includes only a single actuator (button or switch) for data input.
SUMMARY OF THE INVENTION
[0013] The present invention is defined by the claims below. An embodiment includes an electronic device that stores and presents indicators corresponding to animal actions, which may indicate when a female animal is in heat. A reusable, cost-effective, raw-data collection device is provided that times, counts, and records prescribed heat-related actions (such as permitted mounts) and displays the recorded mounting behavior in a simple, easy-to-read format. The invention has several practical applications in the technical arts, not limited to presenting raw data that can be used to determine an optimal window to commence artificial insemination of certain animals. The present invention stores the applicable data for subsequent recall on demand.
[0014] In a first aspect, a detection device is provided. The detection device is a self-powered, self-contained device that includes a processing component, a storage component, a counting component, and a data-presentation component. The device allows for raw-data collection of times and number of valid mounts that a female allows prior to ovulation. As will be explained in greater detail below with reference to a preferred embodiment, the present invention includes a certain number of indicators such as twelve that are used to indicate times at certain intervals, such as hours, of recorded mounting behavior. Data is conveyed using flashing LEDs that can easily be read from a distance. The ability to easily observe recorded mounting behavior is a significant improvement over the prior art. The present invention offers the advantage of a narrow circuit board, approximately 2 cm, making attachment to a cow much easier. Moreover, the present invention includes a relatively low profile (see FIG. 3D ). In other embodiments, data can be remotely transmitted to a receiving component.
[0015] In another aspect, a method is provided for determining when a female animal is in heat. The method includes tracking the number of mounts a female permits over a period of time. Once the female experiences a mount of preselected duration, such as two seconds, a clock is activated, whereby the present invention begins to display the hour and mounting behavior of the animal. Data validation is performed on input received. In some embodiments, validation takes the form of a mandatory delay interval, whereby subsequent data input received prior to the lapsing of the interval will not be attributed to a mount. Data validation offers the significant benefit of reducing the number of false positives. The behavior is presented by a series of indicators that can be readily observed by a breeder. This ability to display mounting behavior from a distance satisfies a long-felt need of breeders to be able to quickly and accurately observe the mating behavior of cows from a distance. Certain blink durations are employed to convey various data events.
[0016] In another aspect of the invention, a computer-program product is provided that tracks preovulation data, such as mounting behavior, and stores it for future recall and/or current presentation. The computer-program product includes embodied computer-useable instructions that monitor mounting behavior, stores the behavior, and presents indicators corresponding to the behavior automatically or on demand.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0017] The present invention is described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein:
[0018] FIG. 1 is a block diagram depicting an illustrative operating environment suitable for practicing the present invention;
[0019] FIG. 1A is an enlarged view of a first exemplary LED array in accordance with an embodiment of the present invention;
[0020] FIG. 1B is an enlarged view of a second exemplary LED array in accordance with an embodiment of the present invention;
[0021] FIG. 2 is a flow diagram illustrating a method for presenting mounting and recording behavior in accordance with an embodiment of the present invention;
[0022] FIG. 2A is a flow diagram illustrating in greater detail a method for recalling and displaying logged mounting behavior in accordance with an embodiment of the present invention;
[0023] FIG. 2B is a flow diagram illustrating in greater detail a method for engaging a sleep mode in accordance with an embodiment of the present invention;
[0024] FIG. 2C is a flow diagram illustrating in greater detail a method for receiving and presenting mounting behavior in accordance with an embodiment of the present invention;
[0025] FIG. 3A illustrates an exploded view of exemplary physical components in accordance with an embodiment of the present invention;
[0026] FIG. 3B illustrates an exemplary underside of the upper casing shown in FIG. 3A in accordance with an embodiment of the present invention;
[0027] FIG. 3C illustrates an elevated view of the housing shown in FIG. 3A in accordance with an embodiment of the present invention;
[0028] FIG. 3D illustrates a side view of the housing shown in FIG. 3A in accordance with an embodiment of the present invention;
[0029] FIG. 3E illustrates an end view of the housing shown in FIG. 3A in accordance with an embodiment of the present invention;
[0030] FIG. 3F is an additional outside view of the upper portion of the housing of FIG. 3A in accordance with an embodiment of the present invention;
[0031] FIG. 3G is an additional inside view of the upper portion of the housing of FIG. 3A in accordance with an embodiment of the present invention;
[0032] FIG. 3H is an outside view of the lower portion of the housing of FIG. 3A in accordance with an embodiment of the present invention;
[0033] FIG. 3I is an additional inside view of the lower portion of the housing of FIG. 3A in accordance with an embodiment of the present invention;
[0034] FIG. 4 is a schematic wiring diagram illustrating one of many alternative arrangements of components that will facilitate the functionality described in accordance with an embodiment of the present invention; and
[0035] FIGS. 5A-27 compose a detailed flow diagram for receiving and presenting mounting-behavior data in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] The present invention provides an electronic mounting-behavior detection device useful for estimating the optimal time to inseminate animals by recording and displaying mounting behavior related to the estrus cycle, specifically the quantity of mounting events and the elapsed time since each event occurred. The device collects and displays raw data related to permitted mounts. The number of mounts permitted by an animal is stored along with other data during a prescribed period, such as a twelve-hour period. Other periods can be prescribed and are contemplated within the scope of the present invention. Mounting behavior may include one female cow engaging in mounting behavior with another cow, which is sometimes referred to as sympathy mounting. Any mounting behavior, including sympathy mounting, is detected by the present invention. Although the device is described herein with reference to the mounting activities of cows, it to be understood that the invention is also applicable to other animals.
[0037] The present invention more accurately tracks mating-behavior events and presents data related to those events, thereby enabling a decision maker to determine an optimum insemination time. The present invention provides raw data corresponding to mating-behavior events. Being able to observe raw data, a breeder can make a more informed insemination decision. The present invention logs historical data related to mating behavior leading up to ovulation and reduces the occurrence of false positives. The present invention provides a narrow footprint that makes attachment to an animal easier and more secure. A low profile greatly helps the present invention stay in place while receiving inputs corresponding to mounting-behavior events.
[0038] As one skilled in the art will appreciate, the present invention may be embodied as, among other things. a method, system, or computer-program product. Accordingly, the present invention may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware. In a preferred embodiment, the present invention takes the form of a computer-program product that includes computer-useable instructions embodied on a computer-readable medium.
[0039] Computer-readable media include both volatile and nonvolatile media, and removable and nonremovable media. By way of example, and not limitation, computer-readable media include data-storage media and communications media. Data-storage media, or machine-readable media, include media implemented in any method or technology for storing information. Examples of stored information include computer-useable instructions, data structures, program modules, and other data representations. Computer-storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Discs (DVD), holographic media or other optical storage devices, magnetic cassettes, magnetic tape, magnetic disk storage, and other magnetic storage devices. These memory components can store data momentarily, temporarily, and/or permanently.
[0040] Communications media typically store computer-useable instructions—including data structures and program modules—in a modulated data signal. The term “modulated data signal” refers to a propagated signal that has one or more of its characteristics set or changed to encode information in the signal. An exemplary modulated data signal includes a carrier wave or other transport mechanism. Communications media include any information-delivery media. By way of example but not limitation, communications media include wired media, such as a wired network or direct-wired connection, and wireless media such as acoustic, infrared, radio, microwave, spread-spectrum, and other wireless media technologies. Combinations of the above are included within the scope of computer-readable media.
[0041] Turning now to FIG. 1 , a block diagram is depicted of an exemplary operating environment 100 suitable for practicing the present invention. Operating environment 100 is provided for illustrative purposes to describe an exemplary embodiment for performing the functionality described in the flow diagrams, which will be described in greater detail with reference to FIGS. 2, 2A , 2 B, and 2 C. Those skilled in the art will appreciate a variety of alternative operating environments that provide the functional aspects described below. FIG. 1 is illustrative in nature and should not be construed as a limitation of the present invention.
[0042] In a preferred embodiment, operating environment 100 includes a controller 110 , which may include a timer 112 , an input-control component 114 , an output-control component 116 , a memory 118 , and a processor 120 . One skilled in the art would recognize alternative names for the aforementioned subcomponents, all of which are not listed nor depicted due to their conventional nature. Timer 112 can receive an incoming clock signal and manipulate the signal to comply with desired parameters and track passage of time. Memory 118 can be, as described above, any computer-readable media for storing and reading computer-useable instructions. Memory 118 is preferably nonvolatile, so as to preserve historical data in the absence of a power source. Processor 120 coordinates data flow through the various subcomponents of controller 110 , all of which are not shown due to their conventional nature. Although a litany of devices may be used, exemplary controller 110 suitable for use in the present invention include the PIC16LF627A or PIC16LF84A Microcontroller offered by Microchip Technology Incorporated of Chandler, Ariz.
[0043] In a preferred embodiment, controller 110 communicates with a power source 122 , an actuator or switch 126 , a timing device or clock 124 , and a presentation interface such as LED array 128 . Power source 122 includes one or more batteries in the preferred embodiment but could be any device that provides power to the system, such as a solar-panel array or a kinetic device that is motion-powered. When used, the batteries are preferably maintained in place with one or more battery holders that are vibration resistant and sufficiently sturdy to withstand vibrations present in manufacturing and in normal use. Clock 124 provides timing functionality to controller 110 . Switch 126 can be any type of actuating device that signals the happening of an event. In some embodiments, the entire casing (described in greater detail below with reference to FIGS. 3A-3I ) that houses the electronics of the device can trigger switch 126 in a pressure-sensitive embodiment. Thus the casing can act as a switch. This embodiment is useful to increase the surface area available to receive mounting-behavior stimuli. Switch 126 can be normally opened or normally closed and can be in the form of a hardware embodiment or software embodiment, such as a proximity sensor. A single-button embodiment makes the present invention easier to operate. Control over device functionality can be achieved by deliberate sequencing of switch 126 , sequencing that would not likely be caused by an animal.
[0044] Presentation interface 128 provides mounting-behavior feedback to an observer. Typically, the observer will be a human being, but an observer could be an inanimate device, such as a light-reading device that can read the data gathered by the present invention. In a preferred embodiment, the presentation interface 128 is an array of LEDs. But presentation interface 128 may also include one or more audio-generating components such as a speaker. The LEDs, however, provide easy-to-read feedback that is readily observable by an observer. Although the number of LEDs can vary, the preferred embodiment uses twelve LEDs wherein each LED corresponds to a one-hour interval. This embodiment is illustrated in FIG. 1A , which depicts twelve individual LEDs referenced by numerals 128 A- 128 L. The LEDs blink according to a programmable pattern to indicate input received. Input reception can be triggered by a variety of events including mounting behavior. The LEDs 128 A- 128 L need not be the same color and may even each be multicolored. LEDs 128 A- 128 L are preferably a flat rectangular type rather than the round cylindrical type. Although the round cylindrical type can be used, flat LEDs offer a slimmer design.
[0045] An alternative embodiment is shown in FIG. 1B where LED array 128 includes two LEDs 128 M and 128 N, each of a different color. In this embodiment, a first LED 128 M blinks to convey time and the second LED 128 N blinks to convey mounting behavior for the corresponding time segment. These two exemplary embodiments provide the same benefit of being able to read the device at a safe or comfortable distance from the animal. But presentation interface 128 does not necessarily have to be an LED array, as long as the interface enables distant observation of recorded mounting behavior. The remaining disclosure, however, will describe the invention with respect to a preferred embodiment of twelve LEDs for ease of explanation.
[0046] Turning now to FIG. 2 , a flow diagram of an embodiment of the present invention is referenced generally by numeral 210 . Not all steps are necessary steps and the order of processes described should not be interpreted limitations of the invention. On power up or incident to a reset, the present invention can conduct an initialization process at a step 212 . A variety of tasks can be performed during initialization. In one embodiment, the LED array 128 is cycled at initialization step 212 to provide visual confirmation that each LED is functioning properly. Timer 112 is reset and allocations are made in memory 118 to record a new input cycle.
[0047] A playback mode is offered by the present invention to display historical data. Playback mode retrieves data stored in memory 118 and presents the data to a user. Additional memory may be provided to store more data. A more informed decision can be made with the benefit of historical data. Using the present invention, a veterinarian can observe prior mating-behavior events and decide what type of insemination procedures to facilitate. Playback mode can be triggered at a step 214 . If it is, the stored data is displayed at a step 216 , which will be described in greater detail with reference to FIG. 2A .
[0048] If playback mode is not entered then an optional sleep mode may be defaulted to at a step 218 . This optional feature prolongs battery life and is exited when valid input is received. In a preferred embodiment, sleep mode is the default mode. If no action is taken, then sleep mode is entered at a step 220 , which will be explained in greater detail with reference to FIG. 2B . The present invention waits for valid input (which could be a reset sequence) to be received, indicated by a step 222 . When valid input is received it is logged at a step 224 , explained in more detail with reference to FIG. 2C . In a preferred embodiment, input is received via switch 126 , which could be the entire housing.
[0049] Turning now to FIG. 2A , a more detailed flowchart is provided that describes an embodiment of the playback mode. At a step 230 , a determination is made as to whether a valid playback request is received. If a valid playback request is not received, sleep process 220 continues. In a preferred embodiment, a valid playback request corresponds to a prescribed sequence of inputs received via switch 126 . In one embodiment, for example, the number of presses of switch 126 during initialization will present a corresponding data series. Thus, if switch 126 is pressed a certain number of times—for instance, five times—during the initialization cycle 212 (which is preferably indicated by two sequencings of LED array 128 ), then the fifth most recent data cycle will be displayed. How the data is displayed can vary, but LEDs 128 A- 128 L deliberately blink in a prescribed pattern. An exemplary prescribed pattern will be described in greater detail below.
[0050] At a step 232 , controller 110 determines the correct data set to display from memory 118 . In the embodiment described immediately above, controller 110 receives the number of switch presses. One press will retrieve the most recently stored data. Two presses will retrieve the second most recently stored data and so forth. The desired data events are displayed at a step 234 . The method explained to retrieve historical data should not be construed as a limitation of the present invention. Historical data could be retrieved in a variety of ways; successive switch presses during a specific time is but one way. Some embodiments may use a separate switch to retrieve stored data. Other embodiments may present previous cycles by holding down switch 126 . The ability to retrieve stored data is more important than the way the data is actually retrieved.
[0051] Playback of historical data may be interrupted at a step 236 by receiving another input stimulus. If playback is not interrupted, then historical data is persistently presented to a user. But if additional input is received, then a determination is made at a step 238 as to whether a valid reset request has been submitted. A valid reset request should require deliberate action. In a preferred embodiment, a reset request is triggered by five successive presses of switch 126 . In other embodiments, switch 126 may be pressed four times, or ten times, etc. In embodiments that have multiple switches, one of the switches can be dedicated to perform a reset function. In still other embodiments, a magnet can be used in connection with an appropriate switch to reset the device. If a valid reset request is received, the present invention reinitializes at a step 212 .
[0052] FIG. 2B more particularly illustrates the sleep mode. Sleep mode is a mode whereby a minimal amount of energy is used by the present invention. At a step 240 , sleep mode is either initiated or maintained. If no input is received, the system remains in sleep mode, as indicated by step 242 . But if input is received, then a determination is made at a step 244 as to whether the input is valid.
[0053] This first validation is provided to reduce false starts and is programmable. In a preferred embodiment, the input received passes validation if switch 126 remains closed for approximately two or three seconds. If the device is attached to an animal, such as a cow, it may be triggered by a variety of events. The main event sought to be tracked by the present invention is a mount permitted by a female animal. A two-second depression of switch 126 would most likely be caused by a successful mount. Any time interval may be used to suit an array of applications. But requiring some sort of minimum switch-depression interval reduces the likelihoods of false positives, recorded events that do not actually correspond to an attempted mount. If the input is valid, then it is logged at a step 224 . If it is not valid, then a determination is made as to whether the input may be a reset request at a step 246 . If not, then sleep mode is maintained at a step 240 , but if the input provides a valid reset request, then the system is initialized at a step 212 .
[0054] FIG. 2C is a flow diagram depicting a preferred embodiment of how the present invention logs data. When a valid input is initially received, a timer is started at a step 250 . The timer can be timer 112 or any device that tracks the passage of time. The input event is recorded at a step 252 by storing the time and event in memory 118 . After the event is recorded, a determination can be made as to whether a cycle threshold has lapsed at a step 254 . The cycle threshold is a programmable maximum time interval during which data is received for tracking purposes. In a preferred embodiment, the cycle threshold is twelve hours. Although variable, this threshold is preferable because some research suggests that artificial insemination is most likely to be successful if done approximately 12 hours after the first standing heat. Moreover, 12 hours approximately coincides with the milking cycle of some dairy cows. Although other periods such as 8 hours (or any duration) are also applicable and contemplated within the scope of the present invention. During the milking cycle, a farmer may either outfit cows with the present invention or observe the data provided by the present invention to make artificial-insemination decisions. This cycle can be varied according to the type of animal the present invention is to be used in connection with.
[0055] If the threshold has lapsed, then a threshold time alarm is presented at a step 256 . This alarm can take a variety of forms and may even be omitted. But in one embodiment, the first LED 128 A and last LED 128 L flash in rapid succession, providing a clear indication to a breeder that the current recording cycle is complete. If a valid reset request is received at a step 258 , then the system reinitializes it at a step 212 . Otherwise, subsequent input is disregarded at a step 260 , and the input behavior of the current cycle is displayed persistently.
[0056] If the prescribed cycle threshold has not lapsed at a step 254 , then controller 110 updates by storing the event in memory 118 . The update is immediately reflected by LED array 128 . Thus, the hour and mounting behavior are immediately and easily observable. As will be described in greater detail below with reference to a preferred embodiment, a long blink designates the hour and short blinks designate the number of valid inputs—mounts in this example—in that hour. Input could be tracked by the half hour or any other time horizon; hourly tracking is merely exemplary. Additional input may be received at a step 264 . If no input is received, the present invention continues displaying input data until the cycle threshold time passes. But if additional input is received, then it is validated at a step 266 .
[0057] One of the many benefits of the present invention is its ability to reduce the occurrence of false positives. A false positive would be a recorded event that should not have been logged. In operation, a false positive may be generated by an animal pursuing a mount, but who merely strikes the device occasionally while attempting the mount. To reduce the occurrence of false positives, the data is validated at a step 266 . In a preferred embodiment, validation includes the occurrence of two events: first, that switch 126 remain closed for a threshold duration (two seconds for example) and second, that a prescribed interval (such as three seconds) lapsed between successive input receptions. That is, switch 126 must be closed for approximately two seconds after having been open for approximately three seconds in this embodiment. The two- and three-second thresholds are exemplary in nature and should not be construed as a limitation of the present invention. There may be many hundreds of different validation techniques that can be used in lieu of the described method. What is important is including a validation step, such as step 266 . Although even the validation step can be eliminated without departing from the scope of the present invention, doing so would most likely result in less accurate data.
[0058] A novel aspect of the present invention is providing detailed feedback to a breeder using readily observable flashing lights (LEDs) blinking in a pattern composed of long and short flashes in a preferred embodiment. The actual sequencing can vary. What follows is a description of merely one example to sequence the LEDs of array 128 to present stored data. In the preferred embodiment, long blinks designate the hour—according to the respective flash LED—and short blinks designate the input events (hereafter “mounts”). Only one LED is active at any given time to ease reading. An illustrative example follows.
[0059] The first standing mount will cause first LED 128 A to blink in a certain manner. In this embodiment, the first LED will blink one long blink to indicate the hour and one short blink to indicate the standing mount. Thus, a breeder observing the device would understand that hour one is being recorded and that one mount or attempted mount has taken place in that hour. If the animal accepts another mount in hour one, then LED 128 A will blink one long blink (still indicating that mounts are being recorded for hour one, the first hour) and two short blinks (indicating that two mounts have taken place in that hour). After the first hour lapses, cycling extends to the next LED, whereby LED 128 B will begin to blink—one long blink. If the cow or other animal permits a mount in the second hour, then that mount will be indicated by one short blink of LED 128 B. This information is persistently presented. A breeder would observe the first LED blink once long, followed by two shorts, followed by a long blink from the second LED and then one short blink of the second LED. The cycle would then repeat. After the second hour completes, the third LED 128 C will begin to blink one long blink. This process will continue for the prescribed cycle duration, such as twelve hours.
[0060] In this embodiment, the total number of short blinks corresponds to the total number of mounts. But the present invention will also provide an indication of the peak mounting period. Assuming a cow's optimal breeding window occurs approximately twelve hours after its first mount, a breeder may simply wait until the threshold-cycle alarm is presented. That cow can then be inseminated. With access to raw data—more data than a mount indication—a breeder can distinguish valid mounting activity from other activity and better predict optimal time for insemination, including consideration of variables such as the period of peak mounting activity or the past behavior of the particular cow in question.
[0061] FIG. 3A is an exploded view of physical characteristics of a preferred embodiment of the present invention. The detection device is referenced generally by the numeral 310 and includes an upper casing 302 , electronics console 314 , and lower casing 316 . Upper casing 302 , in conjunction with lower casing 316 , encloses electronics console 314 . Casings 302 and 316 are made of a polycarbonate material, or another suitable material capable of maintaining its structural integrity while bearing the weight of a mounting animal.
[0062] Upper casing 302 is preferably transparent or translucent so that flashes of LED array 128 can be easily observed through the case, as well as through a transparent sleeve that is affixed to the animal and adapted to receive device 310 . In other embodiments, a window may be provided to enhance observability of LED array 128 (see FIG. 3F ). In both cases, the present invention offers the desirable aspect of presenting mounting data in a readily observable manner. Upper casing 302 is generally rectangular in shape with beveled edges to minimize catching of the device on the mounting animal or other objects. Upper casing 302 can include a seal to prevent moisture and matter from entering into the device and a durable push-button cover 320 for activating switch 126 . Push-button cover 320 may be made of the same material as the seal or another suitable material capable of repeatedly withstanding the weight of the mounting animal and returning to an initial position.
[0063] In an alternative embodiment, upper housing 302 and lower housing 316 work together to trigger switch 126 . In this embodiment, there is no push button 320 . In its stead, the casing as a whole transitions from a first position to a second position during a mounting event. After the mounting event, the device 310 returns to its first position.
[0064] Lower casing 316 is adapted to receive the upper casing 302 . A suitable set of fasteners 318 secure the casings together and can withstand the weight of the mounting animal and other conventional wear and tear. Fasteners 318 may be screws. The size of the casings, and the device 310 as a whole, is preferably minimized to reduce catching of the device on the mounting cow or other objects.
[0065] As previously explained, one skilled in the art would appreciate a variety of components and arrangement of components that may be used to provide the functionality of the present invention. Electronics console 314 is but one example. It illustrates an arrangement of components on a printed circuit board (PCB) 322 . Affixed to PCB 322 in this embodiment is LED array 128 , switch 126 , controller 110 , clock 112 , and two replaceable batteries 122 . Two batteries are not necessary but provide extended power. As shown, the layout enables PCB 322 to have a width 324 of approximately two centimeters, a height 326 of less that six millimeters, and length of less than ten centimeters. Without the second battery 122 , PCB 322 can be only 7.5 cm long. The small footprint of PCB 322 reduces the overall width of the device 310 , offering a significant advantage of making attachment to a cow's tailbone more stable and secure. The components of electronics console 314 can preferably be coated with a water-resistant material to increase reliability.
[0066] FIG. 3B illustrates the underside of upper casing 302 . FIG. 3C is a top or elevated view of detection device 310 . Note that in some embodiments, a window or series of perforations can be included to increase the visibility of the LEDs of LED array 128 . FIG. 3D provides a side view of detection device 310 , illustrating the relatively low profile of the present invention that helps it to stay in place while in use. FIG. 3E provides an end view of detection device 310 .
[0067] Turning now to FIG. 3F , an additional outside view of top housing 302 is according to an embodiment of the present invention. Although push-button cover 320 is shown, other actuators may be employed as previously described. In some embodiments, the entire cover shown in FIG. 3F may itself trigger actuator 126 . An LED window array 330 is an alternative to a transparent or translucent housing 302 . LED window array 330 may be also take the form of a slit in housing 302 rather than the set of individual windows shown. An inside view of top housing 302 is provided in FIG. 3G
[0068] Turning now to FIG. 3H , an outside view of lower housing 316 is provided. Attachment to an animal is preferably made by affixing a sleeve to the animal that receives the detection device 310 . FIG. 3I is an additional inside view of the lower housing 316 according to one embodiment of the present invention.
[0069] FIG. 4 is a wiring diagram of but one arrangement of components that accomplish the aforementioned functionality. The diagram of FIG. 4 should not be construed as a limitation of the present invention because different electrical components could be arranged in different ways to accomplish the same results as those described herein. Those skilled in the art will appreciate reading the diagram of FIG. 4 in connection with the components of FIG. 3A to make and use the invention. Although controller 110 is illustratively depicts the PIC16LF27A microcontroller, other suitable devices, such as the PIC16LF84A (both offered by Microchip Technology Incorporated of Chandler, Ariz. as previously mentioned), would also provide the functionality desired.
[0070] FIGS. 5A-27 are a very detailed flow diagrams for receiving and presenting mounting behavior in accordance with an embodiment of the present invention. The level of detail included in FIGS. 5A-27 should not be interpreted as limitations of the invention but rather a detailed illustration of a preferred embodiment of the present invention. FIGS. 5A-27 include several steps and adequately convey to one skilled in the art the functionality described without a need for a supplementary description here. To recite in words what the flow diagrams of FIGS. 5A-27 convey would unnecessarily lengthen the disclosure. It is to be well understood, however, that the level of detail provided in FIGS. 5A-27 is done so to illustrate merely one detailed embodiment of the present invention. For instance, FIG. 7 includes a decision step where a determination is made as to whether five presses of switch 126 have occurred (references to “key” are to switch 126 , which may be the entire housing). Clearly “five” is merely one number selected. Checking for three, six, or some other number of switch presses is equally applicable. Similarly, FIG. 11 includes a step to load the register to test for sufficient brevity to qualify as a short key event to test for eight short key presses. Any number of key presses will work as well. “Eight” key presses is illustratively shown to reflect that such action would not likely be caused by breeding behavior.
[0071] Not all steps are necessary. The order of the steps is not mandatory. Those skilled in the art will appreciate alternative ways of providing the same functionality described in FIGS. 5A-27 , which are contemplated within the scope of the present invention.
[0072] As can be seen, the present invention is well-adapted to provide a new and useful method for, among other things, determining an optimal time to artificially inseminate animals, such as cows. Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the spirit and scope of the present invention.
[0073] The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. For instance, additional LEDs may be employed to indicate that a cow permitted more behavior than merely a mount. Many alternative embodiments exist but are not included because of the nature of this invention. A skilled programmer may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention.
[0074] It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need to be carried out in the specific order described. | Apparatus and method for detecting when an animal is or is closed to being in heat. An embodiment of the apparatus includes a switch, connectable to a power source and depressible so as to indicate potential mating behavior of an animal; a presentation interface; a timing component (which may include multiple timers) adapted to record a first duration of time when the switch transitions from a first state to a second state and a second duration of time when the switch transitions from the second state back to the first state; and a controller coupled to the switch, the presentation interface, and to the timer; the controller comprising a memory component, whereby input received via the switch can be stored in the memory component and utilized to display on the presentation interface an indication of breeding activities that persist for at least the first duration and are separated by at least the second duration. | 0 |
FIELD OF THE INVENTION
The present invention relates to an image forming method and an image forming system to form an image on a textile by ink-jetting, and in particular, the invention relates to an image forming method and an image forming system to obtain high quality prints without producing transfer staining and color staining caused after printing.
RELATED ART
In recent years, an ink-jet textile printing apparatus being superior in small lot and multi-product production has received widespread interest compared to various current types of textile printing apparatus such as flat screen and rotary screen types. In typical ink-jet printing methods, plural colors of ink stored in the apparatus is controlled by digital signals and small ink droplets are ejected onto the textile to directly form an image. Thus, there is no necessity for preparing printing pastes for respective screen plates and colors, thereby leading to a marked decrease in man-hours.
However, methods of ink-jet printing on textiles still exhibit various problems, such as; bleeding after printing, and clogging of the printer head by dried ink, causing transfer staining on portions of the textile, which are to remain blank.
The problem of bleeding after printing can be solved by raising viscosity of the ink. However, if the viscosity of the ink is raised simply, the stability of the jetting of the ink jet head may deteriorate. Consequently, known is a method which prevents ink bleeding by providing a water repellent finishing on the textile as a pretreatment with raising the viscosity only slightly. However, this method often results in ink transfer staining.
It is preferred that ink contains a high boiling solvent to prevent clogging of the head due to the potential of dried ink. However, when the high boiling solvent is used, ink drying is significantly retarded, resulting in unacceptable transfer staining and in color staining. The technology to obtain a sharp image without ink bleeding, by drying with heating to a moisture content of 3 to 30% after printing, is described in Japanese Patent Publication Open to Public Inspection (hereinafter, referred to as JP-A) No. 6-23977. However, this technology is not effective in cases where a high boiling solvent is employed in the ink, producing problems that transfer staining in non-printed portions of the textile still remains.
SUMMARY OF THE INVENTION
Accordingly, an aspect of the present invention is to provide an image forming method for textile utilizing ink-jet printing and an image forming system comprising an image forming apparatus and a drying apparatus to improve the dryness of the printed textiles. The further aspect of the present invention is to solve transfer staining and color staining due to specially formulated ink containing a high boiling solvent.
The foregoing problems can be solved by the following embodiments.
One embodiment of the invention is an image forming method comprising the steps of: forming an image by jetting ink comprising a high-boiling point solvent onto a textile; and removing the high-boiling point solvent from the image-formed textile by drying the textile under depressurized condition.
Another embodiment of the invention is an image forming method comprising the steps of: forming an image by jetting ink comprising a high-boiling point solvent onto a textile; preparing a textile roll by rolling up the image-formed textile with superimposing inserting medium on the textile; and removing the high-boiling point solvent from the image-formed textile by drying the textile roll under a depressurized condition.
Still another embodiment of the invention is an image forming system comprising an ink-jet recording apparatus and a drying apparatus. The ink-jet recording apparatus in the system comprises a recording head to jet an ink comprising a high-boiling point solvent onto a textile. The drying apparatus in the system comprises a chamber to housing therein the image-formed textile, a depressurizing device to depressurize the inside of the chamber, the depressurizing device being connected with the chamber and a trapping device to recovering the high boiling point solvent vaporized in the chamber, the trapping device being positioned between the chamber and the depressurizing device or at the exhausting side of the depressurizing device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 Side view indicating an example of an ink-jet textile printing apparatus
FIG. 2 Sectional view indicating a state of interleaving
FIG. 3 Drawing indicating an example of a drying apparatus for ink-jet printing
FIG. 4 Drawing indicating another example of a drying apparatus for ink-jet printing
FIG. 5 Side view of an ink-jet textile printing apparatus used in the comparative example
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of the present invention will be detailed below.
FIG. 1 is a side view of an example of an ink-jet recording apparatus. In the figure, “ 1 ” is the printing section, “ 2 ” is the textile and “ 20 ” is a master roll of textile “ 2 ”; “ 3 ” is an inserting medium supply device to supply inserting medium from an inserting medium roll “ 30 ”; “ 4 ” is a winding device to wind the textile materials after superimpose the inserting medium on the textile.
Textile “ 2 ” is fed from master roll “ 20 ”, and ink droplets are ejected from head “ 10 ” to perform printing. After printed, textile “ 2 ” is conveyed to inserting medium supply device “ 3 ”, and superimposed with the inserting medium, and then wound up by winding device “ 4 ”.
In the present invention, inserting medium represents the conduct to insert a medium “ 30 ” for interleaving between print surface “ 301 ” and back surface “ 302 ” being in contact with “ 301 ” as shown in FIG. 2 or represents the medium “ 30 ” itself. “ 303 ” in FIG. 2 is the printed portion on the textile. This inserting-medium process eliminates necessity for providing the drying apparatus in the printing section “ 1 ” or in the vicinity thereof, leading to enhanced operationality and structural apparatus stability.
Examples of medium used for the inserting medium include papers such as blank newspaper, straw paper and tissue paper, non-woven fabric, and basically any material may be used which does not cause the ejected ink adhered to the interleaf to penetrate and reach the backside of the printed surface. Rough non-woven fabric is specifically preferable to achieve the effect of the present invention.
Ink used for ink-jet printing contains a high boiling solvent. In the present invention, the ink preferably contains in an amount of 5 to 60 wt % of a high boiling solvent, and more preferably 20 to 50 wt %.
The high boiling solvent of the present invention refers to one exhibiting more than 150° C. of boiling point under atmospheric pressure. Examples thereof include: glycols such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propanediol, diproplene glycol, buthanediol and hexylene glycol; lower alkyl ethers of polyhydlic alcohols such as glycerin, ethylene glycol monomethyl ether, ethylene glycol monobuthyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether; amines such as triethanolamine; and pyrrolidones such as 2-pirrolidone.
In the ink for ink-jet printing used in the present invention, there may be employed one of above high boiling solvents or a mixture of more than two solvents.
Subsequently, the printed textile roll which is printed by using ink containing a high boiling solvent and wound up by an inserting-medium process (hereinafter, also referred to as the printed textile roll), is conveyed to a drying apparatus.
Based on FIG. 3, the preferable embodiments of the present invention will be explained below.
The first embodiment is the drying apparatus for an ink-jet printing in which a heater is not incorporated, and the second is that a heater is incorporated.
Initially, the first embodiment will be described. Main functions of the first embodiment concern the existence of at least a pressure reduction function to reduce pressure and a trap function to trap a distilled high boiling solvent. In the apparatus shown in FIG. 3, evacuator “ 5 ” is incorporated to achieve a pressure reduction function, and trapping vessel “ 6 ” is provided to fulfill a trapping function. Further, in FIG. 3, “ 7 ” is a chamber for a drying apparatus and “ 40 ” is the printed textile roll, and “ 401 ” is a fixing device to fix printed textile roll “ 40 ”.
A degree of vacuum of the present invention is the pressure inside the drying apparatus at the time of drying (during removal of the high boiling solvent). The degree of vacuum during drying is preferably in the range of 0.01 through 100 Pa, more preferably 0.01 through 10 Pa. Further, the pressure of the inside of the drying apparatus may be allowed to be relatively high when the pressure reducing time is long, however, the pressure needs to be lower when the time is shorter.
Examples of evacuator “ 5 ” include an oil-sealed rotary vacuum pump, a diaphragm type dry vacuum pump and a diffusion pump.
Examples of trapping methods to fulfill a trap function to capture a high boiling solvent include the methods to liquefy by cooling, and to solidify by cooling. Examples of cooling methods include use of ice and dry ice, and furthermore preferable is the use of liquid nitrogen.
As for a trap function, it is preferable that trapping vessel “ 6 ” is connected upstream of evacuator “ 5 ” in a vacuum system, as shown in FIG. 3, such as an oil-sealed rotary vacuum pump, or a combination of an oil-sealed rotary pump and a diffusion pump, in which a solvent (such as oil) to vacuumize is in contact with a gas for pressure reducing. This prevents a high boiling solvent from passing through a vacuum pump incorporating evacuator “ 5 ”, avoiding contamination by oil and resulting in reduction of an oil change frequency and an environment-friendly state.
The arrangement shown in FIG. 3 produces better results even when the evacuated gas is not contact the oil, such as the use of a diaphragm type dry vacuum pump, however, trapping vessel “ 6 ” can be provided following evacuator “ 5 ” (the exhaust side) as shown in FIG. 4 . The method to dissolve a solvent in water or other solution “ 60 ” filled in trapping vessel “ 6 ”, to prevent release of the evacuated gases being released into the atmosphere, to adversely affect to the human. Alternatively, the gas can be absorbed into activated charcoal instead of water.
Next, the second embodiment will be explained. This embodiment is one in which that heating device (heater) “ 8 ” is installed in chamber “ 7 ” as shown in FIGS. 3 and 4. Printed textile roll “ 40 ” is warmed by heater “ 8 ”, and the chamber is evacuated by evacuator “ 5 ”.
In this embodiment, the necessity of cooling of trapping vessel “ 6 ”, explained in FIG. 3, can be eliminated. The reason for this is that a temperature of the gas evaporated under reduced pressure is higher than that of trapping vessel, so that the gas is substantially cooled to be liquefied/solidified in the trapping portion.
Examples of the use of an inserting medium 30 have been described in the foregoing embodiments. Alternatively, a high boiling solvent containing ink is discharged, printed onto the textile surface, followed by drying the textile under reduced pressure to remove the high boiling solvent, without using the inserting medium.
EXAMPLES
The present invention will be further described based on the following examples.
Example 1
Nassenger KS-1600 Type II (manufactured by Konica Corp.) was employed as an ink-jet printer. The ink specifically used for Nassenger containing 5% or more glycerine (produced by Konica Corp.) was used. Used inks were 8 colors, including dispersed dyes of yellow, magenta, cyan and black, and light-colored inks thereof. Polyester China crepe was used as textile media, which is dipped in a solution having the following composition as a pretreatment, mangled and then dried.
gum sizing agent
1%
cationic polymer
2%
fluorinated water repellent agent
1%
water
96%
The pretreated textile was fed to an ink-jet printer and a 1200 mm wide, 500 mm long printed portion of black solid image at a total ink coverage of 50 g/m 2 and a 500 mm long non-printed portion were alternated for 40 m, wound up simultaneously with Nassenger KS-1600 Type II (manufactured by Konica Corp.) together with blank newspaper as an inserting medium, and thus the printed textile roll was prepared.
Drying apparatus “A” was made with a 2000 mm length and 700 mm inner diameter chamber, and incorporating a charging door on one side of the chamber. Tightness between the charging door and the chamber was achieved by using an o-ring.
An oil-sealed rotary vacuum pump, at a maximum of 0.04 Pa, was employed as an evacuator, and the outer side of a trapping vessel was cooled by liquid nitrogen. Further, foamed styrene was used to insulate the exterior of the vessel.
These apparatuses were connected with a 10 mm inner diameter stainless steel pipe in the order of the chamber, the trapping vessel and the evacuator. Further, a vacuum gauge was connected to the chamber, and an orifice valve adjuster was provided between the chamber and the trapping vessel.
The printed textile roll was placed into drying apparatus “A”, and evacuation was continued for 60 min. with adjusting the orifice valve so that the degree of vacuum was maintained at 0.1 Pa.
Thereafter, the inserting medium was removed and the textile was folded and a load of 5 Kg was applied thereto. Then, the roll was subjected to a color forming treatment by a continuous high temperature and high humidity steamer of 170° C., and thus roll sample A was obtained.
Example 2
A heater was provided around the chamber and a support stand was provided for the printed textile roll in drying apparatus “A”, to prepare drying apparatus “B”.
Another printed textile roll was prepared in the same way as in Example 1, and placed into drying apparatus “B”. The heater was adjusted to a temperature of 60° C. with bringing a thermo couple into contacted with the printed textile roll and the roll was allowed to stand for about 20 min.
Next, the chamber was evacuated for 60 min by adjusting the orifice valve to make the degree of vacuum 0.1 Pa.
After removing the inserting medium, the textile was folded and a load of 5 Kg was applied thereto, and the roll was subjected to a color forming treatment by a continuous high temperature and high humidity steamer of 170° C., and thus roll sample B was obtained. In addition, water of less than 10° C. instead of liquid nitrogen was used in the trapping vessel.
Example 3
The evacuator in drying apparatus “A” was replaced with a diaphragm type dry vacuum pump, and a chamber, an evacuator and a trapping vessel were connected in the above order. An orifice valve was installed between the chamber and the evacuator, and thus drying apparatus “C” was prepared.
The printed textile roll was prepared in the same way as in Example 1, and placed into drying apparatus “C”, after which the chamber was evacuated for about 180 min so that the degree of vacuum was to be 100 Pa.
An exhaust pipe was placed into water as shown in FIG. 4 so as to dissolve a solvent into water.
After that, the inserting medium was removed and the textile was folded and a load of 5 Kg was applied thereto, and the roll was subjected to a color forming treatment by a continuous high temperature and high humidity steamer of 170° C., and thus roll sample C was obtained.
Example 4
The ink specifically used for Nassenger (produced by Konica Corp.) was used. Used inks were 8 colors, including reactive inks as typical dye inks of yellow, magenta, cyan and black, and light-colored inks thereof.
A plain woven cotton fabric was used as textile media, which was dipped in a solution having the following composition as pretreatment, mangled and then dried.
high viscosity sodium alginate
1.0%
sodium hydrogencarbonate
0.5%
fluoro water repellent agent
1.0%
urea
0.5%
water
97.0%
Pretreated textile was fed into the ink-jet apparatus, and a 1200 mm width 500 mm length of a printed portion of a black solid image, at a total ink coverage of 50 g/m 2 and a 500 mm length of a non-printed portion were alternated for 40 m, wound up simultaneously with Nassenger KS-1600 Type II (manufactured by Konica Corp.) together with blank newspaper as an inserting medium, and thus the printed textile roll was prepared.
Drying was accomplished in the same way as in Example 1, after which the inserting medium was removed, and the textile was folded and a load of 5 Kg was applied thereto. The roll was then subjected to a color forming treatment by a continuous normal pressure wet steamer at 105° C., and thus roll sample D was produced.
Example 5
The printed textile roll of Example 4 was dried in the same way as in Example 2, and folded and a load of 5 Kg was applied thereto after removing the inserting medium. Thus, roll sample E was produced after color forming treatment at 105° C. by a continuous normal pressure wet steamer.
Example 6
The printed textile roll of Example 4 was dried in the same way as in Example 3, and folded and a load of 5 Kg was applied thereto after removing the inserting medium. Thus, roll sample F was obtained after color-development by a continuous type normal pressure wet steamer of 105° C.
Comparative Example 1
As the comparative example of Examples 1 through 3, the roll samples of comparative sample A were obtained in a conventional drying manner described below instead of reduced-pressure drying.
The drying method is illustrated in FIG. 5, using a hot air dryer instead of the inserting medium supply apparatus and the winding apparatus, illustrated in FIG. 1 . Drying of the printed textile was conducted at a temperature of 40° C., 120° C. and 180° C. (in the portion designated as A in FIG. 5 ).
Comparative Example 2
As the comparative example of Examples 4 through 6, the roll samples of comparative sample B were obtained in the conventional drying manner instead of the reduced-pressure drying in the same way as in above Comparative Example 1.
(Evaluation)
Evaluation was made with respect to transfer staining onto the backside surface and transfer staining onto the surface of the print using Colorimeter SP62 (manufactured by X-Rite, Inc.) and visual check based on the criteria described below. Also, evaluation as to smoke and odor was performed. The evaluated results are shown in Table 1.
<Criteria of Evaluation>
<<Measuring Method with a Colorimeter>>
Colorimetric values of the textile itself before printing (L 1 *, a 1 *, b 1 *), and non-printed portion of the textile after printing (L 2 *, a 2 *, b 2 *), were compared and indicated as δE. δE can be determined by the following Equation 1. Δ E = ( L 1 * - L 2 * ) 2 + ( a 1 * - a 2 * ) 2 + ( b 1 * - b 2 * ) 2 Equation 1
<<Evaluation by Visual Checking>>
A: no stains were noted
B: slight discoloring was noted
apparent stains were observed
<<Overall Evaluation>>
In cases of δE≦2.0, most people could not recognize an abnormal coloring. Therefore, the overall evaluation was “superior” when δE≦2.0 and at the same time the visual check was B or A, while other cases were determined “inferior”. In the case when smoke or odor was noted, the determination was also “inferior”, considered from the viewpoint of enviornmental issues.
TABLE 1
Backside
Print Surface
Surface
Other
Visual
Colori-
Visual
Colori-
Smoke/
Overall
Check
metry
Check
metry
Odor
Evaluation
Example 1
A
1.5
B
1.8
No
Superior
Example 2
A
1.2
A
1.7
No
Superior
Example 3
B
1.8
B
1.7
No
Superior
Example 4
A
1.0
A
1.0
No
Superior
Example 5
A
0.8
A
0.9
No
Superior
Example 6
A
1.1
A
1.4
No
Superior
Comp. 1
40° C.
C
5.4
C
4.8
No
Inferior
100° C.
B
2.0
B
1.9
Yes
Inferior
180° C.
A
1.4
A
1.2
Yes
Inferior
Comp. 2
40° C.
C
3.3
C
4.4
No
Inferior
100° C.
A
1.8
B
1.7
Yes
Inferior
180° C.
A
1.5
A
1.5
Yes
Inferior
Comp.: Comparative Example
Effect of the Invention
Based on the present invention, as explained above, insufficient drying, in regard to ink-jet printing using high boiling solvent in ink has been resolved, and an excellent stainless image is obtained at a high yielding ratio, resulting in a high quality printing process. | An image forming method comprising the steps of: forming an image by jetting an ink comprising a high-boiling point solvent onto a textile; and removing the high-boiling point solvent from the image-formed textile by drying the fabric under depressurized condition. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a division of U.S. patent application Ser. No. 11/430,320, entitled “MOUNTING AND METHOD FOR MOUNTING A WATER VACUUM BREAK”, filed May 9, 2006, which is incorporated herein by reference, which was a non-provisional application based upon U.S. provisional patent application Ser. No. 60/679,527, entitled “MOUNTING METHOD FOR WATER VACUUM BREAK”, filed May 10, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a water vacuum break, and, more particularly, to a water vacuum break utilized in a washing machine.
[0004] 2. Description of the Related Art
[0005] Water inlet devices are used to provide a vacuum break in the inlet water supply that disperses water from an inlet supply hose into the tub of a washing machine. The water is directed to a load of clothes, which are located in the bottom of the tub or along the sidewall of the tub.
[0006] The typical automatic clothes washer or dishwasher for home use is equipped to carry on a series of operations in sequence. The series of operation is most commonly referred to as a cycle. A typical cycle includes fill and rinse elements, each of which utilize a water inlet device, such as a vacuum break, to supply water to the washer. A washing machine includes a housing in which the mechanical operating devices are mounted. It is typical to include a motor assembly for causing motion within the washing device and water control valves for turning on the hot and cold water as necessary under the control of a controller. The water control valves may be associated with the water vacuum break
[0007] The desirability of a vacuum break prevents water from re-entering the water supply source, thereby preventing the contamination of the water source.
[0008] What is needed in the art is a simple cost effective way of mounting a vacuum water break for the easy installation and removal thereof.
SUMMARY OF THE INVENTION
[0009] The present invention relates to a water vacuum break installed in a washing machine without the need for tools or separate fasteners.
[0010] The invention comprises, in one form thereof, a washing machine including a water tub, a housing and a water vacuum break. The water tub is mounted in the housing. The housing includes an outer wall having a plurality of slots therein. The water vacuum break partially extends over a portion of the water tub. The vacuum break includes at least one retaining protrusion and at least one retaining snap associated with the at least one retaining protrusion. The at least one retaining protrusion extends over a portion of the outer wall and the at least one retaining snap has an edge that engages a portion of one of the plurality of slots.
[0011] An advantage of the present invention is that the water vacuum break is easily installable without the use of tools.
[0012] Another advantage of the present invention is that the water vacuum break can be removed by depressing retaining snaps without the use of a tool.
[0013] Another advantage of the present invention is that at least one of the retaining snaps is further retained by another portion of the washing machine to prevent incidental removal of the water vacuum break.
[0014] Yet another advantage of the present invention is that the water vacuum break is installed in a series of slots by approaching the slots in an orthogonal direction and then once the retaining protrusions extend therethrough moving the water vacuum break in a direction parallel with the wall having the slots therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
[0016] FIG. 1 is a perspective view of a washing machine showing one embodiment of a water vacuum break of the present invention;
[0017] FIG. 2 is a partial cross-sectional view of the washing machine of FIG. 1 illustrating the water vacuum break of FIG. 1 being inserted into a portion of the washing machine;
[0018] FIG. 3 is another partial cross-sectional view showing the water vacuum break of FIGS. 1 and 2 being slid into a retained position;
[0019] FIG. 4 is a view of slots in the washing machine of FIGS. 1-3 illustrating slots in an outer wall to accommodate the water vacuum break of the present invention; and
[0020] FIG. 5 is a perspective view of the water vacuum break of FIGS. 1-3 showing connection features thereof.
[0021] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Referring now to the drawings, and more particularly to FIG. 1 , there is shown a washing machine 10 including a water vacuum break assembly 12 connected to washing machine 10 . Washing machine 10 includes a housing 14 with an exterior wall of metal construct.
[0023] Now, additionally referring to FIGS. 2-5 , housing 14 has a series of slots therein including upper mounting slots 16 , lower mounting slots 18 and elongated curved openings 20 . Slots 16 and 18 interact with connection features of vacuum break assembly 12 discussed hereinafter. Elongated curved openings 20 accommodate the insertion and sliding of hose connectors that are part of water vacuum break assembly 12 . Within housing 14 there are various constraints within washing machine 10 including a top constraint 22 , which may be a top portion of washing machine 10 . Further the positioning of tub 24 serves as a constraint for the positioning of water vacuum break assembly 12 . Water vacuum break assembly 12 supplies water to tub 24 during the operation of washing machine 10 .
[0024] Water vacuum break assembly 12 includes thermal sensor assembly 26 , valve assemblies 28 , upper grooved lips 30 , lower grooved lips 32 , upper retaining snaps 34 , and lower retaining snaps 36 . Thermal sensor assembly 26 is associated with water vacuum break assembly 12 to sense the temperature of the water passing through water vacuum break assembly 12 and the information from the sensor is sent to a controller that then provides control signals to valve assemblies 28 to control the volume and temperature of the water flowing through water vacuum break assembly 12 .
[0025] Valve assemblies 28 , are associated with water vacuum break assembly 12 although they can be separate located. Valve assembly 28 is located at each side of 12 and is snapped into position, one for the supplying of cold water and the other for the supplying of hot water. Valve assemblies 28 include a solenoid 38 and a hose connector 40 . Solenoid 38 is electrically connected to a controller, which activates solenoid 38 at appropriate times. Hose connector 40 extends through elongated curved opening 20 when water vacuum break assembly 12 is inserted through housing 14 in direction 52 and then once inserted water vacuum break assembly 12 is moved in direction 54 . Direction 52 is substantially orthogonal with the exterior wall of housing 14 and direction 54 is substantially parallel with the exterior wall of housing 14 .
[0026] Grooved lips 30 and 32 are L-shaped protrusions that extend generally outwardly and downwardly from the back portion of water vacuum break assembly 12 . Lips 30 and 32 are arranged so that they will extend through slots 16 and 18 , respectively, and then slide over an outer portion of the exterior wall of housing 14 . When grooved lips 30 and 32 are pushed into position through slots 16 and 18 , and then downwardly, retaining snaps 34 and 36 snap into position to hold water vacuum break assembly 12 in a fixed position relative to the exterior wall of housing 14 .
[0027] Upper retaining snaps 34 include a flexible arm 42 , a retaining edge 44 and a retaining extension 46 . Flexible arm 42 is molded from the same material as the bulk of water vacuum break assembly 12 and is shaped and formed to take advantage of the flexible nature of a reduced cross-sectional area of the material. Retaining edge 44 is positioned relative to the bottom of grooved lip 30 so that when grooved lip 30 is fully inserted and extends over a portion of the exterior wall of housing 14 that retaining edge 44 snaps into position within an upper mounting slot 16 . Retaining extension 46 serves to not allow retaining edge 44 to extend too far through slot 16 and to additionally allow another portion of washing machine 10 , not shown, to be mounted after water vacuum break assembly 12 to thereby prevent incidental disconnection of water vacuum break assembly 12 from washing machine 10 . In a similar manner lower retaining snaps 36 include a flexible arm 48 and a retaining edge 50 . Flexible arm 48 serves a dual purpose to allow the flexing of snap 36 and also prevents retaining edge 50 from extending too far through slot 18 . As with retaining snap 34 , retaining snap 36 is shaped and positioned such that when grooved lip 32 is in position retaining edge 50 engages an edge of slot 18 to prevent the removal of vacuum break assembly 12 from the exterior wall of housing 14 .
[0028] The insertion of water vacuum break assembly 12 includes moving assembly 12 in first direction 52 until grooved lips 30 and 32 extend, respectively through slots 16 and 18 . At this point in the operation snaps 34 and 36 are flexed away from their normal position until water vacuum break assembly 12 is moved in second direction 54 thereby allowing flexible arms 42 and 48 to return to their normal position thereby causing retaining edges 44 and 50 to engage upper portions of slots 16 and 18 , respectively. In this position hose connectors 40 extend through the exterior wall of housing 14 allowing the connection of the water hose to each hose connector 40 .
[0029] While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A method of installing a water vacuum break in a housing including the steps of providing a plurality of slots in a wall of the housing; moving a water vacuum break in a first direction; and moving the water vacuum break in a second direction. The step of moving the water vacuum break in a first direction includes moving it substantially perpendicularly with the outer wall so that a plurality of retaining protrusions extend through the plurality of slots. | 3 |
FIELD OF THE INVENTION
This invention relates generally to accessories for sheet-fed, rotary offset and flexographic printing presses, and in particular to a dryer for printed materials which utilizes high velocity, hot air flow and extraction.
BACKGROUND OF THE INVENTION
In the operation of a rotary offset press, an image is reproduced on a sheet of paper or some other printable stock by a plate cylinder which carries the image, a blanket cylinder which has an ink transfer surface for receiving the inked image, and an impression cylinder which presses the paper against the blanket cylinder so that the inked image is transferred to the paper. In some applications, a protective and/or decorative coating is applied to the surface of the freshly printed sheets. The freshly printed sheets are then transported to a sheet delivery stacker in which the printed sheets are collected and stacked.
In each press unit, a thin printing plate is mounted on a plate cylinder. The printing plate has image areas which are oleophilic and hydrophobic, and background areas which are oleophobic and hydrophilic. The plate surface is continuously wetted with aqueous damping solution, which adheres only to the background areas. The plate is inked with oleoresinous ink composition which adheres only to the image areas of the plate as wet ink. The ink is offset-transferred to the rubber surface of a contacting blanket cylinder, and is then retransferred to the receptive surface of a web or a succession of sheets, where the ink gradually hardens or cures by oxidation after passing through a final drying station downstream of the last press unit where the volatile solvent is evaporated from the inked image.
The relatively wet condition of the printing ink composition and its solvent and/or diluent components, and the presence of a layer of moisture laden air which clings to the surface of the web or sheet to the next printing unit may interfere with the quality of the images as they are printed at each succeeding printing unit. For example, the quality of colored images, half-tone illustrations and the like undergo degradation in the uniformity of their appearance and color because of the presence of the wet ink, volatiles, and moisture within the printed substrate. Moreover, protective coatings will undergo dilution and surface degradation causing a dull finish if the underlying substrate is not dried sufficiently before the coating is applied.
Such defects, including uneven surface appearance of protective/decorative coatings, detract from the appearance of the underlying images or photographs, particularly in the case of multi-colored images or photographs. The defects are caused by residual, volatile solvents, diluents, water and the like within the oleoresinous inks of the images, and the presence of moisture in the printed material, at the time that the next successive image is printed or the protective/decorative coating is applied. Because the defects are compounded as the printed material moves through successive printing units, it is desirable that curing and drying be initiated and volatiles and moisture laden air be extracted at each interstation position, as well as at the delivery position.
DESCRIPTION OF THE PRIOR ART
Since setting and curing of the inked image is gradual, it is desirable to accelerate the drying process. It is known to provide one or more interstation dryers in multiple-unit presses for the purpose of initiating the setting of the wet ink and extracting the volatiles and moisture laden air from each printing unit.
Hot air dryers and radiant heaters have been used as delivery dryers and as interstation dryers. Interstation dryers employing radiant heat lamps are best suited for slow to moderate press speeds in which the exposure time of each printed sheet to the radiant heat is long enough to initiate ink setting. For high speed press operation, for example, at 5,000 sheets per hour or more, there is not enough available space at the interstation position to install a radiant heater having sufficient number of heat lamps for adequate drying purposes.
As press speed is increased, the exposure time (the length of time that a printed sheet is exposed to the radiant heat) is reduced. Since the number of lamps is limited by the available interstation space, the output power of the radiant lamps has been increased to deliver more radiant energy at higher temperatures to the printed sheets in an effort to compensate for the reduction in exposure time. The increased operating temperatures of the high-powered radiant heat lamps cause significant heat transfer to the associated printing unit and other equipment mounted on the press frame, accelerated wear of bearings and alterations in the viscosities of the ink and coating, as well as upsetting the balance between dampening solution and ink. The heat build-up may also cause operator discomfort and injury.
To handle high speed press operations, an off-press heater has been utilized in which high velocity, heated air is conveyed through a thermally insulated supply duct to a discharge plenum which directs high velocity, heated air onto the printed stock as it travels by the interstation dryer position. Such off-press heaters have proven to be relatively inefficient because of excessive heat loss and pressure drop along the supply duct. Attempts to overcome the heat loss and pressure drop have resulted in substantially increased physical size of the heater equipment (blower fan and supply duct) along with a substantial increase in the electrical power dissipated by the off-press heater.
OBJECTS OF THE INVENTION
The principal object of the present invention is to increase the operating efficiency of a printing press dryer of the type which utilizes high velocity hot air flow to accelerate the drying of inks on freshly printed sheets.
A related object of the present invention is to provide a high efficiency, high velocity hot air dryer which includes improved means for extracting volatiles and moisture laden air from each printing unit, thereby accelerating the drying process.
Another object of the present invention is to provide a high velocity hot air dryer of the character described which is compact and capable of being operated effectively at high press speeds in the interstation position.
Yet another object of the present invention is to provide an improved high velocity hot air dryer of the character described in which the electrical power operating requirements are reduced as compared with comparable radiant dryers and offpress hot air heaters.
Still another object of the present invention is to provide an improved high velocity hot air dryer having a heater element, high velocity air plenum and extractor, with all components being mountable and operable on-press in the interstation position.
Another object of the present invention is to provide a high efficiency, high velocity hot air dryer which includes improved extractor for eliminating the transfer of heat to nearby press parts and equipment.
SUMMARY OF THE INVENTION
The foregoing objects are achieved according to the present invention by a high velocity hot air dryer in which high velocity air from an off-press supply is heated by an internal resistance heating element. Heated air at high pressure is discharged uniformly through precision holes located in an air distribution manifold onto a freshly printed sheet as it moves along a sheet transfer path from one printing unit to the next printing unit.
According to one aspect of the present invention, the moist air layer is displaced from the surface of the printed sheet by high-velocity hot air jets which scrub and break-up the moisture-laden air layer that adheres to the printed surface of the sheet. The high-velocity hot air jets create turbulence which overcomes the surface tension of the moisture and separates the moisture laden air from the surface of the printed material. The moisture laden air becomes entrained in the forced air flow and is removed from the printing unit by a high volume extractor.
The scrubbing action of the high velocity hot air jets is improved by adjacent rows of multiple discharge apertures which are oriented to deliver a converging pattern of high velocity hot air jets into an exposure zone across the sheet travel path. The high velocity hot air jets are produced by a pair of elongated dryer heads in which high velocity air is heated by heat transfer contact with a resistance heating element within an air delivery baffle tube. Since the release of moisture and other volatiles from the ink and printed material occurs continuously in response to the absorption of thermal energy, the moisture laden air layer is displaced continuously from the printed sheet as the printed sheet travels through the exposure zone in contact with the converging hot air jets.
The moisture-laden air is completely exhausted from the printing unit by a high volume extractor. An extractor manifold is coupled to a pair of elongated dryer heads and draws the moisture-laden air, volatiles and high velocity hot air from the exposure zone through a longitudinal air gap between the dryer heads. According to this arrangement, the drying of each printed sheet is initiated and accelerated before the sheet is run through the next printing unit.
Operational features and advantages of the present invention will be understood by those skilled in the art upon reading the detailed description which follows with reference to the attached drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side elevational view in which multiple dryers of the present invention are installed at interstation positions in a four color offset rotary printing press;
FIG. 2 is a simplified side elevational view showing the dryer of the present invention installed in an interstation position between two printing units of FIG. 1;
FIG. 3 is a bottom plan view showing installation of the dryer assembly of FIG. 2 in the interstation position;
FIG. 4 is a perspective view of the interstation dryer shown in FIG. 2;
FIG. 5 is a sectional view of the improved dryer of the present invention taken along the line 5 — 5 of FIG. 4;
FIG. 6 is a longitudinal sectional view of the dryer assembly shown in FIG. 2;
FIG. 7 is a sectional view of the dryer assembly shown in FIG. 2, taken along the line 7 — 7 of FIG. 6;
FIG. 8 is a perspective view of a resistance heating element used in the dryer of FIG. 2;
FIG. 9 is a perspective view similar to FIG. 8, with the resistance heating element enclosed in a support sheath;
FIG. 10 is a view similar to FIG. 4 which illustrates an alternative embodiment of the dryer head in which the discharge port is formed by an elongated slot; and,
FIG. 11 is a perspective view, partially broken away, of the dryer head shown in FIG. 10 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As used herein, the term “processed” refers to various printing processes which may be applied to either side of a sheet, including the application of inks and/or coatings. The term “substrate” refers to sheet material or web material.
Referring now to FIG. 1, the high velocity hot air dryer 10 of the present invention will be described as used for drying freshly printed substrates, which are successively printed at multiple printing units in a sheet-fed, rotary offset printing press. In the exemplary embodiment, the dryer 10 of the present invention is installed at an interstation position between two printing units of a four color printing press 12 which is capable of handling individual printed sheets having a width of the approximately 40″ (102 centimeters) and capable of printing 10,000 sheets per hour or more, such as that manufactured by Heidelberg Druckmaschinen AG of Germany under its designation Heidelberg Speedmaster 102V.
The press 12 includes a press frame 14 coupled on the right end to a sheet feeder 16 from which sheets, herein designated S, are individually and sequentially fed into the press, and at the opposite end, with a sheet stacker 18 in which the printed sheets are collected and stacked. Interposed between the sheet feeder 16 and the sheet stacker 18 are four substantially identical sheet printing units 20 A, 20 B, 20 C and 20 D which can print different color inks onto the sheets as they are moved through the press.
As illustrated in FIG. 1, each sheet fed printing unit is of conventional design, each unit including a plate cylinder 22 , a blanket cylinder 24 and an impression cylinder 26 . Freshly printed sheets S from the impression cylinder 26 are transferred to the next printing unit by transfer cylinders T 1 , T 2 , T 3 .
A protective coating may be applied to the printed sheets by a coating unit 28 which is positioned adjacent to the last printing unit 20 D. The coating unit 28 is preferably constructed as disclosed in U.S. Pat. No. 5,176,077, which is incorporated herein by reference.
The freshly printed and coated sheets S are transported to the sheet stacker 18 by a delivery conveyor system, generally designated 30 . The delivery conveyor 30 is of conventional design and includes a pair of endless delivery gripper chains 32 carrying laterally disposed gripper bars having a gripper element for gripping the leading edge of a freshly printed sheet S as it leaves the impression cylinder 26 . As the leading edge of the printed sheet S is gripped by the grippers, the delivery chains 32 pull the gripper bar and sheet S away from the impression cylinder 26 and transports the freshly printed and/or coated sheet to the sheet stacker 18 .
Prior to delivery, the freshly printed sheets S pass through a delivery dryer 34 which includes a combination of infra-red thermal radiation, forced air flow and extraction.
Referring now to FIG. 2, FIG. 5 and FIG. 6, the interstation dryer 10 includes as its principal components a dryer head 36 , a resistance heating element 38 , and an extractor head 40 . As shown in FIG. 3, the dryer head 36 is mounted on the press side frame members 14 A, 14 B by side frame flanges 42 , 44 . In this interstation position, the dryer head 36 is extended laterally across and radially spaced from the interstation transfer cylinder T 2 , thereby defining an exposure zone Z.
The dryer head 36 includes a tubular sidewall 36 W which encloses an air distribution manifold chamber 46 . The air distribution manifold housing is sealed on opposite ends by end plates 48 , 50 , respectively, and is sealed against the extractor head 40 . The manifold housing has an inlet port 62 for admitting high velocity, pressurized air through a supply duct 52 from an off-press compressor 53 , and has a discharge port 54 for delivering pressurized hot air into the exposure zone Z.
As shown in FIG. 6, the air distribution manifold sidewall 36 W is intersected by multiple discharge apertures 54 which collectively define the discharge port. The apertures 54 are oriented for discharging pressurized jets of high velocity, hot air toward the interstation transfer cylinder T 2 , and are longitudinally spaced along the dryer head 36 . According to this arrangement, pressurized air jets are directed along a straight line across the printed side of a sheet S as it moves through the dryer exposure zone Z. In an alternative embodiment, as shown in FIG. 10 and FIG. 11, the discharge port is formed by an elongated slot 55 which intersects the dryer head sideall 36 W and extends longitudinally along the dryer head.
Referring now to FIG. 6 and FIG. 7, the resistance heating element 38 is coupled to the dryer head 36 by and end block 56 . The end block 56 has a body portion which is intersected by an axial bore 58 , a counterbore 60 and a radial inlet bore 62 which communicates with the counterbore. The heating element 38 has an end portion 38 A which projects through the axial bore 58 and counterbore 60 , with the elongated body portion of the heating element 38 extending into the plenum chamber 46 .
According to an important feature of the present invention, the plenum chamber 46 is partitioned by an elongated air delivery baffle tube 64 which extends substantially the entire length of the dryer head 36 . The air delivery baffle tube 64 has an inlet port 66 for receiving high velocity airflow from a remote supply and has a tubular sidewall 64 A extending through the plenum chamber. The tubular sidewall 64 A has an inner airflow passage 68 which connects the inlet port 66 in airflow communication with the plenum chamber 46 through its open end 64 E. The air delivery baffle tube 64 has an end portion 64 B projecting through the axial bore 60 of the end block 56 , with its inner airflow passage 66 in airflow registration with the radial bore 62 .
A pneumatic connector 70 is coupled to the radial inlet bore 62 of the end block 56 for connecting the inner airflow passage 68 to an off-press source of high velocity air. The end block 56 is sealed against the end plate 50 , the tubular sheath 78 and against the pneumatic connector 70 . High velocity, pressurized air is constrained to flow from the air duct 52 into the airflow passage 68 where it is discharged into the air distribution plenum chamber 46 after absorbing heat from the heating element 38 .
As shown in FIG. 6, the high velocity air flows longitudinally through the annular flow passage 68 in heat transfer contact with the heating element 38 . The high velocity air is heated to a high temperature, for example 350° F. (176° C.), before it is discharged through the airflow apertures 54 .
To provide uniform air jet discharge through the apertures 54 , the inlet area of the inlet port 66 should be greater than the combined outlet area provided by the multiple airflow discharge apertures 54 . In the preferred embodiment, the discharge apertures 54 have a diameter of {fraction (1/16)} inch (0.158 cm), and for a 40″ (102 mm) press there are 88 apertures spaced apart along the dryer head 36 on 0.446 inch (1.13 cm) centers. This yields a total airflow outlet area of 0.269 square inch (1.735 square cm). Preferably, the effective inlet area of the inlet port 66 is at least about 0.54 square inch (3.484 square cm).
In the alternative dryer head embodiment shown in FIG. 10, the air discharge slot 55 has a length of 40 inches (102 mm) along its longitudinal dimension L, and has an arc length C of 6.725 mils (17×10 −3 cm).
With the preferred inlet/outlet ratio of about 2:1 or more, the high velocity, heated air will be supplied to the plenum chamber 46 faster than it can be discharged, so that the heated air will be compressed within the manifold plenum chamber. This assures that the jets of hot air which are discharged through the outlet apertures 54 are uniform in pressure and velocity along the length of the dryer head, so that the printed sheet is dried uniformly as it is transferred through the exposure zone Z.
The air distribution baffle tube 64 is supported on the inlet end by the end plate 50 , and on its discharge end by flange segments 64 F which engage the internal bore of the dryer head 36 and positions the baffle tube in the center of the plenum chamber 46 .
Referring now to FIG. 6, FIG. 7, FIG. 8 and FIG. 9, the heating element 38 is preferably an electrical resistance heater having elongated resistance heater sections 38 C, 38 D which are integrally formed and folded together about at a common end 38 E. The resistance sections 38 C, 38 D are substantially co-extensive in length with the air delivery baffle tube 64 . Each section 38 C, 38 D is electrically connected to a power conductor 72 , 74 , respectively, for connecting the resistance heating element 38 to an off-press source of electrical power.
The resistance heater sections 38 C, 38 D are mechanically stabilized by an end connector 76 , and are enclosed within a tubular, thermally conductive sheath 78 . Radial expansion of the half sections 38 C, 38 D is limited by the sidewall of the sheath 78 , thus assuring efficient heat transfer, while the sheath provides longitudinal support for the elongated resistance heater sections within the inner airflow passage 68 . The heating element half-sections 38 C, 38 D thus form a continuous loop resistance heating circuit which is energized through the power conductors 72 , 74 .
The tubular sheath 78 is received within the bore 58 and is welded to the end block 56 . The tubular sheath 78 thus provides an opening through the end block 56 to permit insertion and withdrawal of the heating element 38 for replacement purposes. The heating element 38 is dimensioned for a sliding fit within the sheath 78 at ambient temperature. The end cap 76 is releasably secured to the end block 56 by a hold-down metal strap (not illustrated). The distal end 78 B of the sheath is sealed by an end cap 78 C to prevent leakage of high velocity air out of the distribution manifold chamber 46 .
Referring now to FIG. 2, FIG. 4, and FIG. 5, the extractor head 40 is coupled to the back side of a pair of identical dryer heads 36 A, 36 B. The dryer heads 36 A, 36 B are separated by a longitudinal air gap 80 which opens in air flow communication with an extractor manifold chamber 82 , thereby defining a manifold inlet port. The extractor manifold chamber 82 is enclosed by the end plates 48 , 50 and by housing panels 40 A, 40 B, 40 C and 40 D. The extractor housing panels 40 C, 40 D are secured and sealed by a welded union to the dryer heads 36 A, 36 B.
According to another aspect of the present invention, the multiple air flow apertures 54 of each dryer head 36 A, 36 B are arranged in linear rows R 1 , R 2 , respectively, and extend transversely with respect to the direction of sheet travel as indicate by the arrows S in FIG. 3 . The rows R 1 , R 2 are longitudinally spaced with respect to each other along the sheet travel path. Each air jet expands in a conical pattern as it emerges from the airflow aperture 54 . Expanding air jets from adjacent rows intermix within the exposure zone Z, thereby producing turbulent movement of high velocity hot air which scrubs the processed side of the sheet S as it moves through the exposure zone Z. Preferably, balanced air pressure is applied uniformly across the exposure zone Z to ensure that the moist air layer is completely separated and extracted from the freshly printed sheets.
In the exemplary embodiment, the pressure of the high velocity air as it is discharged through the inlet port 66 into the heat transfer passage 68 is about 10 psi (7031 Kgs/m 2 ). The inlet suction pressure in the longitudinal air gap 80 of the extractor is preferably about 5 inches of water (12.7×10 3 Kgs/cm 3 ).
As shown in FIG. 3 and FIG. 5, the extractor manifold inlet port 80 is coupled in air flow communication with the exposure zone Z for extracting heat, moisture laden air and volatiles out of the dryer. The extractor manifold chamber 82 is coupled in air flow communication with an exhaust fan 84 by an air duct 86 . The air duct 86 is coupled to the extractor manifold chamber 82 by a transition duct fitting 88 .
The high velocity, heated air which is discharged onto the printed sheet S is also extracted through the air gap 80 into the extractor chamber 82 . Ambient air, as indicated by the curved arrows, is also suctioned into the exposure zone Z and through the longitudinal air gap, thus assuring that none of the hot air, moisture or volatiles will escape into the press area. Extraction from the exposure zone Z is enhanced by directing the hot air jets along converging lines whose intersection defines an acute angle alpha (α), as shown in FIG. 5 .
The air flow capacity of the exhaust fan 84 is preferably about four times the total airflow input to the dryer heads. This will ensure that the exposure zone Z is maintained at a pressure level less than atmospheric thereby preventing the escape of hot air, moisture laden air and volatiles into the press room.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. | A hot air dryer utilizes high velocity air jets which scrub and break up the moist air layer which clings to the surface of a freshly printed sheet. High velocity air is heated to a high temperature as it flows along a resistance heating element within an air delivery baffle tube. The heated, high velocity air pressurizes a plenum chamber within an air distribution manifold. High velocity jets of hot air are discharged through multiple air flow apertures onto the wet ink side of a printed sheet as it moves through the dryer exposure zone. An extractor removes the moist air layer, high velocity hot air and volatiles from the printed sheet and exhausts it from the press. | 5 |
RELATED APPLICATIONS
This application is a division of Ser. No. 07/745,992 filed Aug. 16, 1991 U.S. Pat. No. 5,708,154, which is a continuation-in-part of Ser. No. 07/598,665 filed Oct. 23, 1990, which is a continuation-in-part of Ser. No. 07/317,670 filed Mar. 1, 1989, now abandoned, which is a continuation-in-part of Ser. No. 07/314,935 filed Feb. 24, 1989, now abandoned.
FIELD OF INVENTION
The copending related applications relate to heterologous block oligomers (HBO's). This invention relates to new classes of HBO's identified as modular nanostructure (MNS's) and to the use of MNS's in the detection and inhibition of retroviral reverse transcriptase. The invention also relates to radio-label free reverse transcriptase assays involving NS's, to the use of such assays to screen antiviral drugs and to novel reverse transcriptase inhibitors.
BACKGROUND OF THE INVENTION
The related parent applications describe inventions which utilize the capacity of nucleic acids for self assembly to construct a series of unimolecular DNA foldbacks or HBO's that are good enzyme substrates. In these molecules a long block of DNA is linked through a tether to a complementary short block of DNA. The tether may consist of dT residues, biotin residues, dodecyl phosphate residues, aminopropyl phosphate residues, or trivalent residues which are similar to the above but will allow for side-chain modification. These modifications may include chemiluminescent, fluorescent, or biotin moieties. The tether promotes intramolecular hybridization of the two regions of complementary DNA to form foldbacks having a free 3' hydroxyl on the short DNA strand and an overhanging DNA strand at the end of a short DNA-DNA hybrid. Appropriate HBO's have been shown to be substrates for restriction enzymes, human DNA methyl transferase and DNA polymerase I from E. coli.
Relevant to this invention is the discovery that DNA polymerase I is effective in extending each of the tethered foldbacks to a discrete length corresponding to full extension of the short block in the foldback using the 5' overhang as a template. Variation in the type of tether used permits chromatographic discrimination between otherwise isomeric forms of the molecules.
SUMMARY OF THE INVENTION
Somogyi, Journal of Virological Methods, 27:269-276 (1990) describes a solid phase reverse transcriptase micro-assay. Biotin is suggested as a replacement for tritium in the extant procedures. The invention provides modular nanostructures for use in the detection and inhibition of retroviral reverse transcriptase. For such purposes a relatively short block of DNA is linked to a longer block of RNA through a short tether of variable chemical composition. The tethered blocks are complementary to accommodate the formation of unimolecular foldbacks having a 3' hydroxyl on the DNA strand and an overhanging RNA strand at the end of a short DNA-RNA hybrid.
For reverse transcriptase detection, the tether will include labelled, preferably fluorescent moieties. Incubation of the foldback molecule with biotinylated nucleotide triphosphate precursors in the presence of reverse transcriptase yields a fluorescent product that can be concentrated by affinity binding to matrix bound avidin and detected by fluorescence.
For reverse transcriptase inhibition in living cells, the tether includes hydrophobic moieties to permit transport in liposomes and the penetration of cell membranes. The nanostructure for reverse transcriptase detection or inhibition may include appropriate substitutions. For example, to block enzyme activity, a stable abasic site analog may be included in the RNA strand or a cordycepin moiety may be present at the 3' end of the DNA strand.
DESCRIPTION OF THE FIGURES
FIG. 1 illustrates the experimental design for the production of labelled biotinylated MNS's and the use thereof to detect reverse transcriptase activity.
FIG. 2 illustrates the experimental design for development of a family of reverse transcriptase inhibitors based, in part, on substitution in the modular nanostructure.
DETAILED DESCRIPTION OF THE INVENTION
The expansion of the AIDS epidemic worldwide to between 10 and 30 million HIV positive individuals creates an urgent need for reliable and cost-effective HIV testing and for the screening of potential anti-viral drugs. The need is the greater due to other retroviral diseases such as hairy cell leukemia.
In one important embodiment, this invention provides a simply, highly sensitive, assay for HIV and other retroviral transcriptases which does not employ a radiolabel. This embodiment of the invention facilitates the direct screening of antiviral drugs by the rapid laboratory determination of viral titer in drug treated samples such as cell lines.
Another aspect of the invention permits evaluation of substrate specificity of HIV and other reverse transcriptases and so facilitates the design of deliverable inhibitors.
FIG. 1 illustrates generally the synthesis of a RNA module 30 nucleotides in length from commercially available ribonucleotide precursors. As shown, five functionally modified "dT" moieties are then added to provide a fluorescent label in a tether module. The linked DNA module consists of 10 deoxynucleotides to provide Watson-Crick homology with the 3' end of the 30 mer and thus form the folded substrate molecule (MNS) shown in FIG. 1.
Incubation of this substrate molecule with active reverse transcriptase in the presence of biotinylated deoxynucleotide precursors yields the biotinylated product shown in FIG. 1.
The extent of recovery of the fluorescent product with an avidin based matrix, e.g., in a streptavidin agarose minicolumn, is a function of the activity of reverse transcriptase.
The fluorescent product is quantitated by fluorimetry.
Advantages of this procedure for detecting and quantitating reverse transcriptase are (1) radioactive compounds are not required; (2) sensitivity can be increased by increasing sample size and concentrating the product; and (3) the sequence of the substrate MNS's and its composition--i.e., RNA-DNA; RNA-RNA, can be chosen to optimize the observed activity or increase its specificity for a given species of reverse transcriptase.
A practical application of this aspect of the invention is an assay to detect or quantify reverse transcriptase in physiological samples. The assay entails procurement of a sample from a patient suspected of viral infection, e.g., a patient who may be HIV positive, incubating the sample in the presence of a biotinylated triphosphate with a MNS having a fluorescent tether, recovering the biotinylated product, if any, on an avidin matrix, and quantifying the biotinylated product if present.
The invention includes kits comprising an appropriate fluorescent labelled MNS, and biotinylated dioxynucleotide triphosphate precursor.
EXAMPLE I
Synthesis and Use of a Simple Reverse Transcriptase Substrate
The sequence of each of the three modules in the HBO can be chosen by the investigator. Sequences identical to those of the HIV, and HTLV-I initiation site may be especially useful. In order to provide clarity in this example a simple sequence is used to illustrate the method.
HBO Synthesis
Synthesis of the HBO begins with the 3' matrix-bound phosphoramidite precursor of Thymidine (dT). Programmed DNA synthesis is continued using standard methods in an ABI DNA synthesizer until 12 residues of dT have been added. This constitutes the complementary DNA module. The loop module is synthesized beginning with the addition of two dC residues, after which the system reaches a preprogrammed stop. At this point the investigator manually carries out one cycle of DNA synthesis in which a trifunctional dT residue carrying a masked primary amine is added to the growing chain. Two additional dC residues are added to the growing chain to complete the loop module. The RNA module in the HBO is begun by the addition of 30 Adenine (A) residues using protected riboprecursors and standard RNA synthesis methods. Once the HBO is completed, it is cleaved from the matrix and the masked amino group on the trifunctional dT residue in the loop module is reacted with fluorescein isothiocyanate (FTIC).
Based on our previous work with partially complementary molecules of this type, the HBO will self-associate to form the modular nanostructure depicted below.
5'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA CC
************ dT-FITC
3'TTTTTTTTTTTT CC
Based on our experience with DNA polymerases, this nanostructure is expected to be a self-priming substrated for reverse transcriptase.
Reverse Transcriptase Assay
A standard reaction mixture containing: 50 mM Tris-HCl (pH 8.3), 40 mM KCl, 6 mM MgCl 2 , 1 mM Dithiothreitol, 0.1 mg/ml RNAse free Bovine Serum Albumin and 0.1 mM HBO substrate is then incubated with a reverse transcriptase preparation in 50 μl total volume for 10 minutes at 37° C. in the presence of 0.5 mM Biotinylated dTTP.
HBO's that have been extended by reverse transcriptase will now contain at least 1 biotinylated dT residue, and will therefore be retained by commercially available streptavidin-Agarose. The reverse transcriptase product will be isolated by passage of the complete reaction mixture through a 50 μl column of commercially available streptavidin agarose. After washing with 1 ml of Tris-HCl (pH 8.3), 400 mM KCl, the amount of fluorescein-containing substrate retained by the agarose can be quantified by fluorimetry on the suspended agarose slurry. Alternatively the fluorescein-containing substrate can be eluted from the agarose with a solution containing a strong denaturant, like 6 M guanidine HCl at pH 1.5, and fluorometric quantification of the fluroescein-containing substrate can be carried out in a neutralized solution.
FIG. 2 illustrates procedures for preparing one or more reverse transcriptase inhibitors based on substitutions in the nanostructure. A MNS similar to that shown n FIG. 1 is utilized with the exception that the amino modifier dT used in the tether is a hydropholic moiety, i.e., dodecylphosphate to facilitate liposome transport, and an enzyme inhibitory substitution, e.g., 1,4-Anhydro-D-Ribitol is present in the RNA template of the nanostructure. An enzyme inhibitory moiety, e.g., cordycepin (3' deoxyAdenosine) may alternatively or additionally be included at the 3' end of the DNA strand.
Inhibition of HIV reverse transcriptase is accomplished by incorporation of the MNS's into liposomes for transport to and penetration of cell membranes.
EXAMPLE II
Synthesis of a Simple Reverse Transcriptase Inhibitor
As with the HBO described in Example I, a simple sequence is used to illustrate the preparation of an inhibitory substrate.
HBO Synthesis
Synthesis of the HBO begins with the 3' matrix-bound phosphoramidite precursor of Thymidine (dT). Programmed DNA synthesis is continued using standard methods in an IBI DNA synthesizer until 12 residues of dT have been added. This constitutes the complementary DNA module. The loop module is then synthesized by adding 5 dC residues to the growing chain using standard methods. The RNA module in the HBO is begun by the addition of 15 Adenine (A) residues using protected riboprecursors and standard RNA synthesis methods, after which the system reaches a preprogrammed stop. The investigator then performs one cycle of manual DNA synthesis to introduce a 1,4-Anhydro-D-Ribitol (x) phosphoramidite into the growing RNA module. The RNA module is then completed by the automated addition of 14 additional Adenine (A) residues.
Based on our previous work with partially complementary molecules of this type, the HBO will self-associate to form the modular nanostructure depicted below.
5' AAAAAAAAAAAAAAxAAAAAAAAAAAAAA CC
************ C
3' TTTTTTTTTTTT CC
As noted above, the nanostructure is expected to be a self-priming substrate for reverse transcriptase. Analogous DNA substrates inhibit DNA polymerases because the abasic site analog does not provide a mechanism for base-pair formation with an incoming nucleoside triphosphate precursor. Thus the nanostructure depicted above is expected to permit initiation but block elongation by reverse transcriptase after the addition of three nucleotides to the DNA module. Thus its net effect is to inhibit the enzyme. | A reverse transcriptase assay is described. A modular nanostructure comprising relatively small and relatively long RNA sequences is utilized in the assay. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2007-0107435 filed in the Korean Intellectual Property Office on Oct. 24, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] (a) Field of the Invention
[0003] The present invention relates to a switch, a negative resistance cell, and a differential voltage controlled oscillator using the same. More particularly, the present invention relates to a switch, a negative resistance cell, and a differential voltage controlled oscillator using the same for minimizing generation of a parasitic component.
[0004] (b) Description of the Related Art
[0005] A differential voltage controlled oscillator (DVCO) is a device for changing and outputting an oscillation frequency corresponding to an applied voltage, and is generally used for an analog voice synthesizer and a mobile communication terminal.
[0006] The DVCO used for the voice synthesizer generates sine waves, sawtooth waves, pulse waves, square waves, and triangular waves to generate various sound signals. The DVCO used for the mobile communication device is used for the phase locked loop (PLL) module to function as a local oscillator for allocating channels and converting frequencies into the radio frequency (RF) or the intermediate frequency (IF).
[0007] Also the DVCO is an essential constituent element for the wired/wireless transmitting/receiving system, and study on improving the performance of the DVCO is ongoing.
[0008] However, regarding the general DVCO, performance improvement and downsizing are limited since it is difficult to reduce the parasitic component and the realized area that are caused by the transistor structure and the length of the connection lines between elements by more than a predetermined level, and hence, methods for solving the problem are needed.
[0009] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
SUMMARY OF THE INVENTION
[0010] The present invention has been made in an effort to provide a switch, a negative resistance cell, and a differential voltage controlled oscillator using the same for minimizing the parasitic components and the realization area.
[0011] In one aspect of the present invention, a differential voltage controlled oscillator includes: a resonator for generating an oscillation frequency corresponding to an input voltage; a first output terminal and a second output terminal, respectively coupled to a first terminal and a second terminal of the resonator, for outputting the oscillation frequency; and a negative resistance cell driven in correspondence to the oscillation frequency. The negative resistance cell includes a switch, and the switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; a source electrode formed between the first and second signal lines; a first gate electrode arranged to be parallel with the source electrode and coupled to the first signal line; a second gate electrode provided to the opposite side of the first gate electrode with respect to the source electrode, and coupled to the second signal line; a first drain electrode provided to the opposite side of the source electrode with respect to the first gate electrode, and coupled to the second signal line; and a second drain electrode provided to the opposite side of the source electrode with respect to the second gate electrode, and coupled to the first signal line.
[0012] In another aspect of the present invention, a differential voltage controlled oscillator includes: a resonator for generating an oscillation frequency corresponding to an input voltage; a first output terminal and a second output terminal, respectively coupled to a first terminal and a second terminal of the resonator, for outputting the oscillation frequency; and a negative resistance cell driven in correspondence to the oscillation frequency. The negative resistance cell includes a switch, and the switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; and a first gate electrode to a fourth gate electrode, a first source electrode to a third source electrode, and a first drain electrode to a fourth drain electrode formed between the first signal line and the second signal line.
[0013] The electrodes are formed in the order of the first gate electrode, the first drain electrode, the second gate electrode, the first source electrode, the third gate electrode, the second drain electrode, the fourth gate electrode, the second source electrode, the fifth gate electrode, the third drain electrode, the sixth gate electrode, the third source electrode, the seventh gate electrode, the fourth drain electrode, and the eighth gate electrode.
[0014] In another aspect of the present invention, provided is a negative resistance cell included in a resonator for generating an oscillation frequency corresponding to an input voltage, and a differential voltage controlled oscillator for outputting the oscillation frequency through a first output terminal and a second output terminal and including a switch that is driven corresponding to the oscillation frequency. The switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; a source electrode formed between the first and second signal lines; a first gate electrode arranged to be parallel with the source electrode and coupled to the first signal line; a second gate electrode provided to the opposite side of the first gate electrode with respect to the source electrode, and coupled to the second signal line; a first drain electrode provided to the opposite side of the source electrode with respect to the first gate electrode, and coupled to the second signal line; and a second drain electrode provided to the opposite side of the source electrode with respect to the second gate electrode, and coupled to the first signal line.
[0015] In another aspect of the present invention, provided is a negative resistance cell included in a resonator for generating an oscillation frequency corresponding to an input voltage, and a differential voltage controlled oscillator for outputting the oscillation frequency through a first output terminal and a second output terminal and including a switch driven corresponding to the oscillation frequency. The switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; and a first gate electrode to a fourth gate electrode, a first source electrode to a third source electrode, and a first drain electrode to a fourth drain electrode formed between the first signal line and the second signal line.
[0016] The electrodes are formed in the order of the first gate electrode, the first drain electrode, the second gate electrode, the first source electrode, the third gate electrode, the second drain electrode, the fourth gate electrode, the second source electrode, the fifth gate electrode, the third drain electrode, the sixth gate electrode, the third source electrode, the seventh gate electrode, the fourth drain electrode, and the eighth gate electrode.
[0017] In another aspect of the present invention, a switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; a source electrode formed between the first and second signal lines; a first gate electrode arranged to be parallel with the source electrode and coupled to the first signal line; a second gate electrode provided to the opposite side of the first gate electrode with respect to the source electrode, and coupled to the second signal line; a first drain electrode provided to the opposite side of the source electrode with respect to the first gate electrode, and coupled to the second signal line; and a second drain electrode provided to the opposite side of the source electrode with respect to the second gate electrode, and coupled to the first signal line.
[0018] In another aspect of the present invention, a switch includes: a first signal line extended in a first direction; a second signal line formed to be parallel with the first signal line; and a first gate electrode to a fourth gate electrode, a first source electrode to a third source electrode, and a first drain electrode to a fourth drain electrode formed between the first signal line and the second signal line
[0019] The electrodes are formed in the order of the first gate electrode, the first drain electrode, the second gate electrode, the first source electrode, the third gate electrode, the second drain electrode, the fourth gate electrode, the second source electrode, the fifth gate electrode, the third drain electrode, the sixth gate electrode, the third source electrode, the seventh gate electrode, the fourth drain electrode, and the eighth gate electrode.
[0020] According to the present invention, the switch, the negative resistance cell, and the differential voltage controlled oscillator using them for minimizing parasitic components and realization area are realized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a schematic diagram of a differential voltage controlled oscillator 1000 according to an exemplary embodiment of the present invention.
[0022] FIG. 2 is a detailed schematic diagram of a negative resistance cell 10 included in a general differential voltage controlled oscillator.
[0023] FIG. 3 is a detailed schematic diagram of a negative resistance cell 20 included in a general RF differential voltage controlled oscillator.
[0024] FIG. 4 is a detailed schematic diagram of a negative resistance cell 100 according to an exemplary embodiment of the present invention.
[0025] FIG. 5 shows a structure of a minimum unit cell included in a negative resistance cell 100 according to an exemplary embodiment of the present invention shown in FIG. 4 .
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0026] In the following detailed description, only certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.
[0027] Throughout this specification and the claims that follow, when it is described that an element is “coupled” to another element, the element may be “directly coupled” to the other element or “electrically coupled” to the other element through a third element.
[0028] Throughout this specification, in addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. In addition, the terms “-er”, “-or”, and “module” described in the specification mean units for processing at least one function and operation and can be implemented by hardware components or software components and combinations thereof.
[0029] FIG. 1 is a schematic diagram of a differential voltage controlled oscillator 1000 according to an exemplary embodiment of the present invention.
[0030] As shown in FIG. 1 , the differential voltage controlled oscillator 1000 includes a negative resistance cell 100 and an LC tank 200 .
[0031] The negative resistance cell 100 includes a switch formed by cross-coupled transistors 110 and 120 . For reference, in FIG. 1 , the transistor 110 and the transistor 120 are respectively shown to be formed as a transistor, and differing from this, they can be formed by a plurality of transistors coupled in parallel.
[0032] A drain 110 d of the transistor 110 is coupled to an output terminal Out 1 through a node N 1 , and a source 110 s thereof is grounded. A gate 110 g of the transistor 110 is coupled to a node N 2 .
[0033] A drain 120 d of the transistor 120 is coupled to an output terminal Out 2 through a node N 2 , and a source 120 s is grounded. A gate 120 g of the transistor 120 is coupled to the node N 1 .
[0034] A first terminal of the LC tank 200 is coupled to the node N 1 , and a second terminal is coupled to the node N 2 . The LC tank 200 is formed by coupling an inductor (not shown) and a capacitor (not shown) in parallel, and here, capacitance of the capacitor is changed according to an input voltage, and an oscillation frequency is changed corresponding to the voltage.
[0035] The negative resistance cell 100 of the differential voltage controlled oscillator 1000 according to the exemplary embodiment of the present invention will now be described with reference to drawings. A negative resistance cell included in the general differential voltage controlled oscillator will now be described with reference to FIG. 2 and FIG. 3 .
[0036] FIG. 2 is a detailed schematic diagram 26 a negative resistance cell 10 included in a general differential voltage controlled oscillator.
[0037] As shown in FIG. 2 , the negative resistance cell 10 included in the differential voltage controlled oscillator is formed by a switch including a transistor 11 and a transistor 12 .
[0038] A drain 11 d of the transistor 11 is coupled to a node N 11 coupled to an LC tank (not shown), and a source 11 s is grounded through a source common connector ( 11 s - 1 ).
[0039] A drain 12 d of the transistor 12 is coupled to a node N 12 coupled to the LC tank (not shown), and a source 12 s is grounded through a source common connector ( 12 s - 1 ).
[0040] A gate 11 g of the transistor 11 is coupled to the node N 12 , and a gate 12 g of the transistor 12 is coupled to the node N 11 .
[0041] The drains 11 d and 12 d of the transistors 11 and 12 have a junction with an active area. Also, while not shown in FIG. 2 , the sources 11 s and 12 s of the transistors 11 and 12 obviously have a junction with the active area.
[0042] As shown in FIG. 2 , the transistor 11 and the transistor 12 of the negative resistance cell 10 included in the general differential voltage controlled oscillator are formed to be symmetrical with each other. Therefore, the node N 11 and the node N 12 must be formed to be superimposed with each other, and parasitic resistance, parasitic inductance, and parasitic capacitance components that are caused by the superimposition structure are substantially increased, which cannot be ignored. As shown in FIG. 2 , as the transistors 11 and 12 are formed, a mismatch caused by a gradient in the process for generating the two transistors 11 and 12 may occur.
[0043] Particularly, when the negative resistance cell 10 shown in FIG. 2 is used to manufacture the differential voltage controlled oscillator that is operable in the RF area, the oscillation frequency and frequency tuning range are substantially limited by the parasitic component and the mismatch, and phase noise performance is deteriorated.
[0044] Also, the negative resistance cell 10 shown in FIG. 2 substantially generates an undesired parasitic component as the lengths of the node N 11 and the node N 12 are increased.
[0045] A large parasitic component generated in the negative resistance cell 10 deteriorates the Q factor of the LC tank ( 200 in FIG. 1 ) to thus deteriorate the phase noise performance. The large parasitic component generated in the negative resistance cell 10 limits the frequency bandwidth of the oscillation frequency output by the general differential voltage controlled oscillator to be not greater than a predetermined level. Also, the large parasitic component generated in the negative resistance cell 10 limits the variable range of the output frequency of the LC tank ( 200 in FIG. 1 ). In order to realize an RF differential voltage controlled oscillator for outputting the RF oscillation frequency, a negative resistance cell 20 for reducing generation of the parasitic component compared to the negative resistance cell 10 shown in FIG. 2 is shown in FIG. 3 .
[0046] FIG. 3 is a detailed schematic diagram of a negative resistance cell 20 included in a general RF differential voltage controlled oscillator.
[0047] As shown in FIG. 3 , the negative resistance cell 20 included in the general RF differential voltage controlled oscillator is formed by a switch including a transistor 21 and a transistor 22 .
[0048] A drain 21 d of the transistor 21 is coupled to a node N 21 coupled to an LC tank (not shown), and a source 21 s thereof is grounded.
[0049] A drain 22 d of the transistor 22 is coupled to a node N 22 coupled to the LC tank (not shown), and a source 22 s thereof is grounded.
[0050] A gate 21 g of the transistor 21 is coupled to the drain 22 d of the transistor 22 , and a gate 22 g of the transistor 22 is coupled to the drain 21 d of the transistor 21 .
[0051] The drains 21 d and 22 d of the transistors 21 and 22 have a junction with the active area. Also, while not shown in FIG. 3 , the sources 21 s and 22 s of the transistors 21 and 22 have a junction with the active area.
[0052] The negative resistance cell 20 shown in FIG. 3 arranges the two transistors 21 and 22 asymmetrically so that the gate 21 g of the transistor 21 is coupled to the drain 22 d of the transistor 22 and the gate 22 g of the transistor 22 is coupled to the drain 21 d of the transistor 21 . That is, the negative resistance cell 20 shown in FIG. 3 includes no superimposition structure, differing from the negative resistance cell 10 shown in FIG. 2 , and thus generates a lesser parasitic component compared to the negative resistance cell 10 shown in FIG. 2 . Because of the reduction of the parasitic component, the negative resistance cell 20 shown in FIG. 3 improves the Q factor of the LC tank ( 200 in FIG. 1 ) compared to the negative resistance cell 10 shown in FIG. 2 , and thus acquires improved phase noise performance. The negative resistance cell 20 shown in FIG. 3 can realize the output frequency bandwidth of the differential voltage controlled oscillator to be greater than that of the negative resistance cell 10 shown in FIG. 2 . Also, the negative resistance cell 20 shown in FIG. 3 increases the change of the capacitance of the capacitor corresponding to the voltage input to the capacitor included in the LC tank ( 200 in FIG. 1 ) compared to the negative resistance cell 10 shown in FIG. 2 , and hence, it realizes the improved broadband characteristic.
[0053] However, it is required for the negative resistance cell 20 shown in FIG. 3 to increase the number of the drains 21 d and 22 d by one for the respective transistors 21 and 22 compared to the negative resistance cell 10 shown in FIG. 2 in order to couple the drain and the source of the two transistors 21 and 22 that are arranged asymmetrically. Also, because of the nodes N 21 and N 22 , a parasitic capacitance component is generated between the gate 21 g of the transistor 21 and the drain 21 d of the transistor 21 and between the gate 22 g of the transistor 22 and the drain 22 d of the transistor 22 . Also, the negative resistance cell 20 shown in FIG. 3 may generate a mismatch caused by a gradient because of the asymmetric structure of the two transistors 21 and 22 . The gradient may differentiate the lengths of the connection metal lines between the two transistors 21 and 22 and the LC tank (not shown), and hence, the symmetry between the transistor 21 and the transistor 22 with reference to the LC tank cannot be guaranteed. This asymmetry worsens the phase noise performance, and deteriorates the performance of the differential voltage controlled oscillator.
[0054] A negative resistance cell 100 that is suitable for realizing the RF differential voltage controlled oscillator by minimizing the parasitic component compared to the negative resistance cells 10 and 20 shown in FIG. 2 and FIG. 3 , and for minimizing the realization area according to an exemplary embodiment of the present invention, will now be described with reference to FIG. 4 .
[0055] FIG. 4 is a detailed schematic diagram of a negative resistance cell 100 according to an exemplary embodiment of the present invention.
[0056] As shown in FIG. 4 , the negative resistance cell 100 is formed by a switch including a transistor 120 arranged symmetrically, and a transistor 110 arranged symmetrically to the right and left of the transistor 120 . The negative resistance cell 100 shown in FIG. 4 has a common-centroid structure for the transistor 110 and the transistor 120 . The negative resistance cell 100 shown in FIG. 4 will now be described.
[0057] The node N 1 and the node N 2 are formed as parallel signal lines. The gate 110 g , drain 110 d , and source 110 s of the transistor 110 are provided between the node N 1 and the node N 2 . The gate 120 g , drain 120 d , and source 120 s of the transistor 120 are provided between the node N 1 and the node N 2 . The electrodes are formed in the order of gate 110 g , drain 110 d , the gate 110 g , the source 110 s of the transistor 110 , the gate 120 g , the drain 120 d , the gate 120 g , the source 120 s , the gate 120 g , the drain 120 d , the gate 120 g of the transistor 120 , the source 110 s , the gate 110 g , the drain 110 d , and the gate 110 g of the transistor 110 .
[0058] The drains 110 d and 120 d of the transistors 110 and 120 have a junction with the active area. Also, while not shown in FIG. 4 , the sources 110 s and 120 s of the transistors 110 and 120 have a junction with the active area.
[0059] The negative resistance cell 100 shown in FIG. 4 is formed so that the transistor 110 and the transistor 120 respectively share the sources 110 s and 120 s , and the sources are grounded through the common source connector (S). Accordingly, the number of sources is reduced by 1 compared to the general negative resistance cell 10 shown in FIG. 2 . Also, the general negative resistance cell 20 shown in FIG. 3 has a structure that requires 3 drains for 4 gates, and the negative resistance cell 100 according to the exemplary embodiment of the present invention requires 2 drains for 4 gates. That is, the negative resistance cell 100 has fewer drains than the general negative resistance cell 20 by 2, and hence, the parasitic component, that is, the parasitic capacitor component generated between the drains 110 d and 120 d and the sources 110 s and 120 s , is reduced. Because of the reduction of the parasitic components, the negative resistance cell 100 improves the Q factor of the LC tank ( 200 in FIG. 1 ) compared to the general negative resistance cell 20 shown in FIG. 3 , and thus realizes improved phase noise performance. Also, the negative resistance cell 100 increases the change of capacitance of the capacitor corresponding to the input voltage of the capacitor included in the LC tank ( 200 in FIG. 1 ) compared to the general negative resistance cell 20 shown in FIG. 3 , and thus realizes the improved broadband characteristic.
[0060] Also, the negative resistance cell 100 shown in FIG. 4 forms a structure in which the node N 1 coupled to the gate 110 d of the transistor 110 is completely symmetrical with the node N 2 coupled to the gate 120 d of the transistor 120 , differing from the general negative resistance cell 20 shown in FIG. 3 . That is, the transistors 110 and 120 are formed in the linear symmetric format with respect to the common source 120 S. Because of the common-centroid structure, the negative resistance cell 100 can minimize generation of the parasitic component and generation of a mismatch caused by a gradient, and thus improves phase noise performance.
[0061] In FIG. 4 , the transistor 120 is shown to be formed nearer to the common source 120 s that is the axis of the linear symmetry than the transistor 110 , and differing from this, the transistor 110 can be formed nearer to the common source 120 s than the transistor 120 . Also, the gate 110 g and 120 g of the transistors 110 and 120 are coupled to the nodes N 1 and N 2 . In detail, the gap between the node N 1 and the node N 2 is formed to be within the range of the lengths of the gates 110 g and 120 g of the transistors 110 and 120 , and hence, the heat and the realization area of the parasitic component can be reduced compared to the negative resistance cells 10 and 20 included in the general differential voltage controlled oscillator shown in FIG. 2 and FIG. 3 .
[0062] The transistors 110 and 120 included in the negative resistance cell 100 according to the exemplary embodiment of the present invention shown in FIG. 4 are applicable to other elements having the cross coupled transistor structure in addition to the differential voltage controlled oscillator 1000 according to the exemplary embodiment of the present invention.
[0063] FIG. 5 is a structure of a minimum unit cell included in a negative resistance cell 100 according to an exemplary embodiment of the present invention shown in FIG. 4 . Here, a minimum unit cell represents a switch including transistors 110 and 120 driven in correspondence to two different control signals, and the negative resistance cell 100 can be formed with one minimum unit cell.
[0064] As shown in FIG. 5 , the transistor 110 and the transistor 120 of the minimum unit cell included in the negative resistance cell 100 according to the exemplary embodiment of the present invention share a common source. The minimum unit cell structure shown in FIG. 5 will now be described in detail.
[0065] The node N 1 and the node N 2 are formed as parallel signal lines. The gate 110 g of the transistor 110 is provided in parallel to the common source, and is coupled to the node N 2 . The drain 100 d of the transistor 110 is provided to the opposite side of the common source with respect to the gate 110 g , and is coupled to the node N 1 . The gate 120 g of the transistor 120 is provided to the opposite side of the gate 110 g of the transistor 110 with respect to the common source, and is coupled to the node N 1 . The drain 120 d of the transistor 120 is provided to the opposite side of the common source with respect to the gate 120 g , and is coupled to the node N 2 .
[0066] The drains 110 d and 120 d of the transistors 110 and 120 have a junction with the active area. Also, while not shown in FIG. 5 , the sources 110 s and 120 s of the transistors 110 and 120 have a junction with the active area.
[0067] Here, the common source is coupled to the common source connector (S) and is then grounded. Further, the gate 110 g of the transistor 110 and the drain 120 d of the transistor 120 , and the gate 120 g of the transistor 120 and the drain 110 d of the transistor 110 , are set to not be superimposed with each other. Hence, the length of the connection line for forming the minimum unit cell is minimized.
[0068] The minimum unit cell structure shown in FIG. 5 can be selected as the standard cell for the library provided by the general semiconductor process. When the minimum unit cell structure shown in FIG. 5 is used as the standard cell, the extended form of the standard cell can be realized as the same format as the negative resistance cell 100 according to the exemplary embodiment of the present invention shown in FIG. 4 , and can also be realized as a format that is different from the negative resistance cell 100 according to the exemplary embodiment of the present invention shown in FIG. 4 . The negative resistance cell 100 minimizes the switch structure, minimizes the number of drains 110 d and 120 d and sources 110 s and 110 s of the transistors 110 and 120 , and is formed in the common-centroid structure for solving the mismatch during the process. Accordingly, the negative resistance cell 100 improves the Q factor of the LC tank 200 to improve phase noise performance, and improves the performance of the differential voltage controlled oscillator 1000 for outputting the RF band oscillation frequency. Also, the negative resistance cell 100 increases the change of capacitance of the capacitor corresponding to the input voltage of the capacitor included in the LC tank 200 , and realizes the improved broadband characteristic. Therefore, the negative resistance cell 100 allows the realization of the differential voltage controlled oscillator 1000 for outputting the RF broadband oscillation frequency.
[0069] The transistors 110 and 120 shown in FIG. 4 and FIG. 5 can be realized with various types of switches including a complimentary metal oxide semiconductor (CMOS) and a bipolar junction transistor (BJT).
[0070] The above-described embodiments can be realized through a program for realizing functions corresponding to the configuration of the embodiments or a recording medium for recording the program in addition to through the above-described device and/or method, which is easily realized by a person skilled in the art.
[0071] While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | The present invention relates to a switch, a negative resistance cell, and a differential voltage controlled oscillator using the same. The present invention includes a first signal line provided in a first direction, a second signal line provided in parallel with the first signal line, and first to fourth gate electrodes, first to third source electrodes, and first to fourth drain electrodes formed between the first signal line and the second signal line, and provides a switch having electrodes in the order of the first gate electrode, the first drain electrode, the second gate electrode, the first source electrode, the third gate electrode, the second drain electrode, the fourth gate electrode, the second source electrode, the fifth gate electrode, the third drain electrode, the sixth gate electrode, the third source electrode, the seventh gate electrode, the fourth drain electrode, and the eighth gate electrode. According to the present invention, a differential voltage controlled oscillator for RF oscillation operation in the broadband area is realized by minimizing generation of parasitic components. | 7 |
This is a continuation of application Ser. No. 410,108, filed Aug. 20, 1982 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to an improved liquid alkenyl succinic anhydride mixture having superior paper sizing properties. This invention also relates to an improved method for the sizing of paper and paperboard products. A further aspect of this invention relates to an improved method for imparting water-repellency to cellulosic fabrics.
It is known in the art that long straight chain alkenyl succinic anhydrides can be used as effective paper sizing agents. See, for example, U.S. Pat. Nos. 3,102,064; 3,821,069; 3,968,005; and 4,040,900 (Re. 29,960). These alkenyl succinic anhydrides have also been used as fabric treating agents. See U.S. Pat. No. 2,903,382. The useful molecular weight range of the alkenyl group on these sizing agents has variously been described as encompassing 8 to 35 carbon atoms.
It is also known that these prior art sizing agents are best applied in a highly dispersed form, such as an aqueous emulsion. However, alkenyl succinic anhydrides made from straight chain alpha olefins are solids at ambient temperatures and are therefore not effective in forming these emulsions. In view of this, commercial alkenyl succinic anhydride paper sizing agents are made from isomerized straight chain alpha olefins (i.e., straight chain internal olefins) or from branched chain olefins. See, for example, the frequent reference to "isooctadecenyl succinic anhydride" in U.S. Pat. No. 3,102,064.
It has been taught that the molecular weight of the alkenyl group of the more effective or preferred alkenyl succinic anhydride sizing agents corresponds to a carbon number in the 13 to 22 carbon atom range. Mixtures of several carbon numbers have also been described. See, for example, the reference to C 15-20 alkenyl succinic anhydride in U.S. Pat. No. 4,040,900 (Re. 29,960).
SUMMARY OF THE INVENTION
The present invention provides a two-component alkenyl succinic anhydride composition with superior paper sizing properties which comprises:
(A) the reaction product of maleic anhydride and straight chain alpha olefins in the C 13 to C 18 range having an average molecular weight of from about 182 to 238; and
(B) the reaction product of maleic anhydride and straight chain internal olefins or branched chain olefins in the C 14 to C 22 range having an average molecular weight of from about 224 to 308;
wherein component (B) has a molecular weight at least 10 units higher than component (A).
Preferably the above mixture contains about 5 to 40% of component (A) and, more preferably, about 10 to 35% of component (A).
The present invention is also concerned with a method of sizing paper by dispersing within the wet paper pulp an alkenyl succinic anhydride composition as described above.
The instant invention is further concerned with a method of treating cellulosic fabric to render the same water-repellent by impregnating the fabric with the novel alkenyl succinic anhydride compositions of the invention.
Among other factors, the present invention is based on my surprising discovery that certain straight chain alpha olefin-derived alkenyl succinic anhydrides, heretofore considered not useful, can be combined in specific mixtures with other alkenyl succinic anhydrides to provide a superior paper sizing product.
An additional advantage of the present invention is the fact that, when straight chain alpha olefins are being used as the starting feedstock for making liquid alkenyl succinic anhydrides, less olefin processing is required prior to forming the alkenyl succinic anhydride.
The alkenyl succinic anhydrides of the present invention are generally prepared by thermal reaction of the precursor olefin with maleic anhydride, using techniques well known in the art.
DETAILED DESCRIPTION OF THE INVENTION
The composition of the present invention may be prepared by simply combining the described alkenyl succinic anhydride components or, alternatively, by combining the precursor olefins and then making the desired alkenyl succinic anhydride. For example, a broad range straight chain alpha olefin mixture, which may be obtained from wax cracking, Fischer-Tropsch synthesis or ethylene oligomerization, could be distilled to yield light and heavy fractions. The heavy fraction is then isomerized to move the double bond to internal positions and recombined with the light fraction before making the alkenyl succinic anhydride composition of the present invention.
The olefin feed for component (A) of the present composition should be predominantly straight chain 1-olefin. Minor amounts of chain branching or internal olefin, such as is found in commercial "alpha olefins," may also be present.
The olefin feed for either component (A) or (B) may consist of a single carbon number, a mixture of contiguous carbon numbers or may consist of any combination of carbon numbers within that range.
The olefin feed for component (B) may be straight chain or branched. Branched chain olefin may be obtained from various sources such as by oligomerization of lower olefins in the C 3 to C 11 range. If straight chain, the olefin should be substantially free of alpha olefin. These straight chain olefins may be obtained from n-paraffins by processes well known in the art, such as dehydrogenation and chlorination-dehydrochlorination. Alternatively, the straight chain olefins may be made by isomerizing alpha olefins using acidic or basic catalysts. The isomerization should be sufficient to leave no more than about 15% alpha olefin remaining, preferably less than 10%, and more preferably, less than 5% alpha olefin.
The novel sizing agents display all of the features and advantages of the cited prior art sizing agents. Moreover, the novel sizing agents of this invention impart to paper sized therewith a particularly good resistance to acidic liquids such as acid inks, citric acid, lactic acid etc. as compared to paper sized with the sizing agents of the cited prior art. In addition to the properties already mentioned, these sizing agents may also be used in combination with alum as well as with any of the pigments, fillers and other ingredients which may be added to paper. The sizing agents of the present invention may also be used in conjunction with other sizing agents so as to obtain additive sizing effects. A still further advantage is that they do not detract from the strength of the paper and when used with certain adjuncts will, in fact, increase the strength of the finished sheets. Only mild drying or curing conditions are required to develop full sizing value.
The actual use of these sizing agents in the manufacture of paper is subject to a number of variations in technique any of which may be further modified in light of the specific requirements of the practitioner. It is important to emphasize, however, that with all of these procedures, it is most essential to achieve a uniform dispersal of the sizing agent throughout the fiber slurry, in the form of minute droplets which can come in intimate contact with the fiber surface. Uniform dispersal may be obtained by adding the sizing agent to the pulp with vigorous agitation or by adding a previously formed, fully dispersed emulsion. Chemical dispersing agents may also be added to the fiber slurry.
Another important factor in the effective utilization of the sizing agents of this invention involves their use in conjunction with a material which is either cationic in nature or is, on the other hand, capable of ionizing or dissociating in such a manner as to produce one or more cations or other positively charged moieties. These cationic agents, as they will be hereinafter referred to, have been found useful as a means for aiding in the retention of sizing agents herein as well as for bringing the latter into close proximity to the pulp fibers. Among the materials which may be employed as cationic agents in the sizing process, one may list alum, aluminum chloride, long chain fatty amines, sodium aluminate, substituted polyacrylamide, chromic sulfate, animal glue, cationic thermosetting resins and polyamide polymers. Of particular interest for use as cationic agents are various cationic starch derivatives including primary, secondary, tertiary or quaternary amine starch derivatives and other cationic nitrogen substituted starch derivatives, as well as cationic sulfonium and phosphonium starch derivatives. Such derivatives may be prepared from all types of starches including corn, tapioca, potato, waxy maize, wheat and rice. Moreover, they may be in their original granule form or they may be converted to pregelatinized, cold water soluble products.
Any of the above noted cationic agents may be added to the stock, i.e., the pulp slurry, either prior to, along with, or after the addition of the sizing agent. However, in order to achieve maximum distribution, it is preferable that the cationic agent be added either subsequent to or in direct combination with the sizing agent. The actual addition to the stock of either the cationic agent or the sizing agent may take place at any point in the paper making process prior to the ultimate conversion of the wet pulp into a dry web or sheet. Thus, for example, these sizing agents may be added to the pulp while the latter is in the headbox, beater, hydropulper or stock chest.
In order to obtain good sizing, it is desirable that the sizing agents be uniformly dispersed throughout the fiber slurry in as small a particle size as is possible to obtain. One method for accomplishing this is to emulsify the sizing agent prior to its addition to the stock utilizing either mechanical means, such as high speed agitators, mechanical homogenizers, or by the addition of a suitable emulsifying agent. Where possible, it is highly desirable to employ the cationic agent as the emulsifier and this procedure is particularly successful where cationic starch derivatives are utilized. Among the applicable non-cationic emulsifiers which may be used as emulsifying agents for the sizing agents, one may list such hydrocolloids as ordinary starches, non-cationic starch derivatives, dextrines, carboxymethyl cellulose, gum arabic, gelatin, and polyvinyl alcohol as well as various surfactants. Examples of such surfactants include polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitol hexaoleate, polyoxyethylene sorbitol laurate, and polyoxyethylene sorbitol oleate-laurate. When such non-cationic emulsifiers are used, it is often desirable to separately add a cationic agent to the pulp slurry after the addition to the latter of the emulsified sizing agent. In preparing these emulsions with the use of an emulsifier, the latter is usually first dispersed in water and the sizing agent is then introduced along with vigorous agitation. Alternatively, the emulsification techniques described in U.S. Pat. No. 4,040,900 may be employed.
Further improvements in the water resistance of the paper prepared with these novel sizing agents may be obtained by curing the resulting webs, sheets, or molded products. This curing process involves heating the paper at temperatures in the range of from 80° to 150° C. for periods of from 1 to 60 minutes. However, it should again be noted that post curing is not essential to the successful operation of this invention.
The sizing agents of this invention may, of course, be successfully utilized for the sizing of paper prepared from all types of both cellulosic and combinations of cellulosic with non-cellulosic fibers. The cellulosic fibers which may be used include bleached and unbleached sulfate (kraft), bleached and unbleached sulfite, bleached and unbleached soda, neutral sulfite, semi-chemical chemiground-wood, ground wood, and any combination of these fibers. These designations refer to wood pulp fibers which have been prepared by means of a variety of processes which are used in the pulp and paper industry. In addition, synthetic fibers of the viscose rayon or regenerated cellulose type can also be used.
All types of pigments and fillers may be added to the paper which is to be sized with the novel sizing agents of this invention. Such materials include clay, talc, titanium dioxide, calcium carbonate, calcium sulfate, and diatomaceous earths. Other additives, including alum, as well as other sizing agents, can also be used with these sizing agents.
With respect to proportions, the sizing agents may be employed in amounts ranging from about 0.05 to about 3.0% of the dry weight of the pulp in the finished sheet or web. While amounts in excess of 3% may be used, the benefits of increased sizing properties are usually not economically justified. Within the mentioned range the precise amount of size which is to be used will depend for the most part upon the type of pulp which is being utilized, the specific operating conditions, as well as the particular end use for which the paper is destined. Thus, for example, paper which will require good water resistance or ink holdout will necessitate the use of a higher concentration of sizing agent than paper which does not. The same factors also apply in relation to the amount of cationic agent which may be used in conjunction with these sizing agents. The practitioner will be able to use these materials in any concentration which is found to be applicable to his specific operating conditions. However, under ordinary circumstances a range of from 0.5 to 2.0 parts by weight of cationic agent per 1.0 part of sizing agent is usually adequate. It can be noted that the cationic agent is present in a quantity of at least 0.025% of the dry weight of the pulp in the paper.
The alkenyl succinic anhydride compositions of the present invention may also be used to impart water-repellency to cellulosic fabrics. The water-repellent compositions described above may be applied to the cloth in aqueous emulsions similar to those used for paper sizing. The emulsion may be sprayed onto the fabric or the fabric may be dipped into the emulsion in order to distribute the derivative evenly throughout the fabric. The impregnated fabric is then withdrawn from the solution and air dried. After air drying the cloth is then heated, preferably to a temperature in excess of 100° C., to effect a curing of the impregnated agent within the cloth. It has been found that one may conveniently use a temperature of about 125° C. for a period of 15 to 20 minutes. At lower temperatures longer periods of time are required to effect the curing process. To be commercially practical the curing time should be as short as possible and generally less than one hour. At higher temperatures the heat curing may be accomplished in shorter periods of time. The upper limit of temperature at which the heat curing process may be carried out is limited to the temperatures at which fabrics begin to brown or become discolored. Using the composition of the present invention, it is preferred to impregnate the fabric with from about 0.7 to 2.5% by weight of the fabric of the alkenyl succinic anhydride.
The following examples are provided to illustrate the invention in accordance with the principles of this invention but are not to be construed as limiting the invention in any way except as indicated by the appended claims.
EXAMPLES
Example 1
This example describes the preparation of a standard straight chain alkenyl succinic anhydride suitable for sizing applications.
The feed olefin was derived from cracking petroleum wax and originally contained about 88% straight chain alpha olefin. It consisted of a mixture of homologs from C 15 to C 20 containing about 18% C 15 , 19% C 16 , 18% C 17 , 8% C 18 , 15% C 19 and 12% C 20 . This mixture was isomerized using an acidic catalyst until the alpha olefin content was reduced to 7%. The double bond had been moved to the 2-position and further internal positions.
The above straight chain internal olefin mixture (329 g, 1.35 moles) was heated with maleic anhydride (98 g, 1 0 mole) in an autoclave for 31/4 hours at 230° C. Over 95% of the maleic anhydride reacted with the olefin to give an alkenyl succinic anhydride product. This crude product was stripped of unreacted maleic anhydride and olefin by heating up to 260° C. at 25 mm Hg with nitrogen sparging over a 40-minute period.
The remaining alkenyl succinic anhydride was a straw-colored liquid with a pour point of about 5° C. which remained fluid but formed some solids on standing overnight at this temperature.
This product is very similar to normal commercial straight chain alkenyl succinic anhydride. It gives good paper sizing results in a variety of tests, such as those described in U.S. Pat. No. 4,040,900 (Re. 29,960).
Example 2
An alkenyl succinic anhydride was made as described in Example 1, except that the carbon number range of the feed olefin consisted of 25% C 15 , 30% C 16 , 29% C 17 , and 15% C 18 . The alpha olefin content remaining after isomerization was 7%. The derived alkenyl succinic anhydride was a clear liquid which did not produce solids on standing overnight at 5° C.
Example 3
An alkenyl succinic anhydride was made from the same straight chain alpha olefins as described in Example 1, except that the olefin isomerization step was omitted. The alkenyl succinic anhydride product was a solid, completely unsuitable for sizing by the normal aqueous emulsion techniques.
Example 4
The alpha olefin feed used in Example 1 was distilled to produce a lower boiling fraction which was 88% C 15 and 9% C 16 , with an average molecular weight of 212. An alkenyl succinic anhydride was made from this olefin using the steps of Example 1 except that the isomerization step was omitted. This alkenyl succinic anhydride was a solid, unsuitable for sizing.
Example 5
An example of the composition of the present invention was made by using the alkenyl succinic anhydride of Example 4 as component A and a C 16-18 alkenyl succinic anhydride as component B. The C 16-18 alpha olefin fraction was in the bottoms from distilling out the C 15 cut of Example 4. This C 16-18 fraction contained about 34% C 16 , 34% C 17 , and 27% C 18 , with an average molecular weight of 237. The C 16-18 fraction was isomerized to reduce the alpha olefin content to 7%, and an alkenyl succinic anhydride was made as in Example 1. The final alkenyl succinic anhydride mixture contained 22.5% of component A and 77.5% of component B. This composition was a clear liquid at room temperature. It remained fluid but formed some solids on standing overnight at 5° C.
Example 6
Another example of the composition of the present invention was made as described in Example 5, except that the C 16-18 olefin used to make the alkenyl succinic anhydride of component B was isomerized more completely before reacting with maleic anhydride. In this case, instead of 7% alpha olefin remaining, only 2% alpha olefin remained after isomerizing. This C 16-18 olefin was reacted with maleic anhydride and the resulting alkenyl succinic anhydride was mixed with the alkenyl succinic anhydride of Example 4 in a 22.5/77.5 ratio as in Example 5. This composition was a liquid at room temperature and did not form any solids on standing overnight at 5° C.
Example 7
Paper sizing experiments and size effectiveness evaluations were run using techniques described in U.S. Pat. No. 4,040,900 (Re. 29,960). For each alkenyl succinic anhydride tested, eight results were obtained. The alkenyl succinic anhydride was added to paper at two different levels: 0.2% and 0.4%, based on dry fiber weight. A cationic starch adjuvant was employed at two times the alkenyl succinic anhydride level, in each case. At both alkenyl succinic anhydride levels, tests were also made with 0.5% added alum. The sized papers were evaluated using both the Hercules size test (80% reflectance end point), and the potassium permanganate test described in U.S. Pat. No. 4,040,900.
For each alkenyl succinic anhydride, the times to obtain each end-point were averaged to give the results shown in Table 1.
TABLE 1______________________________________ Time, in seconds, toAlkenyl Succinic Anhydride end-point (averageExample No. Carbon Range of 8 tests)______________________________________1 15-20 1042 15-18 1105 15-18 1216 15-18 165______________________________________
The results of Table 1 demonstrate that the alkenyl succinic anhydrides of the present invention, namely Examples 5 and 6, give superior sizing effectiveness compared to the known alkenyl succinic anhydride compositions of Examples 1 and 2.
Example 8
A composition similar to those described in Examples 5 and 6 was made by blending 20% of the alkenyl succinic anhydride from Example 4 with 80% of an alkenyl succinic anhydride derived from a branched olefin mixture in the C 15 to C 20 range made by oligomerizing propylene. This composition was a liquid at room temperature and did not form any solids on standing overnight at 5° C. | An improved liquid alkenyl succinic anhydride composition having superior paper sizing properties. There is also disclosed a method for the sizing of paper and a method for imparting water-repellency to cellulosic fabrics using the composition of the invention. | 3 |
This invention relates to roller clutches in general, and specifically to a roller clutch in which the energizing spring can self align to maintain itself on an optimal line of force as it energizes the rollers.
BACKGROUND OF THE INVENTION
The two most common types of one way clutches found in automatic transmission applications are roller clutches and sprag clutches. Roller clutches have a plurality of caged rollers, each of which is located in a wedging pocket formed between a cylindrical pathway on one race and a sloped cam ramp on another race. Sprag clutches have a plurality of generally dumbbell shaped sprags located between two cylindrical pathways. Roller clutches are preferred to sprag clutches in many applications, both because of the lower cost of the clutch itself, and also because a roller clutch can tolerate a much greater degree of eccentricity between the clutch races, which allows for an easier clutch installation. This greater tolerance for race eccentricity results from the fact that the rollers are each individually spring energized, and can move independently up or down the cam ramps as the clutch overruns. Each roller, assisted by the continual bias by its respective energizing spring, automatically self seeks its own optimal position during clutch overrun. This optimal roller position can be termed the ready position, that is, the position where it is lightly engaged between the pathway and cam ramp, ready to quickly jam between the races. However, the ability of the roller to move up and down the cam ramp also creates some potential problems, especially in hign speed environments and environments where the rollers will be subjected to a high degree of external roller disturbing forces. These potential problems may be best illustrated by referring to FIGS. 1 through 3, which illustrate the structure and operation of a typical conventional roller clutch.
A conventional roller clutch, indicated generally at 10, includes a complement of cylindrical rollers 12, each of which is located in a wedging pocket formed between the cylindrical pathway 14 of an outer race 16 and a confronting cam ramp 18 formed on a substantially coaxial inner cam race 20. Clutch 10 has a cage 22 that forms its basic structural framework, and which is sized so as to be easily installed between the races 16 and 20, and tied to the cam race 20. Cage 22 is a fairly typical construction, and consists of a circumferentially spaced plurality of molded plastic journal blocks, one of which is indicated generally at 24, which are attached to a metal end ring 26. End ring 26 is partially broken away to show the roller 12 and journal block 24. Each journal block 24 is molded with a flat cross bar 28, which generally lies on a plane that is parallel with the axis of cage 22. A conventional energizing spring, designated generally at 30, has a generally square base mounting fold 32 clipped over cross bar 28, a roller conforming front contact loop 34 pressed against the side of a respective roller 12, and a serpentine central active portion 36 which consists of a series of V shaped folds. Cage 22 is the concentricity control type, meaning that the journal blocks 24 act as plain bearing members, and are sized so as to fit between the races 16 and 20 closely enough to keep the races substantially coaxial during overrun, but with enough clearance to allow for an easy installation of cage 22. This clearance, which is exaggerated for purposes of illustration in FIG. 1, also creates a running eccentricity between the races 16 and 20. During overrun, when the outer race 16 turns counter clockwise relative to inner race 20, the wedging pockets on one side of clutch 10 will widen, while those on the other side will narrow. The wedging pockets will not be of the same width at any instant of time, and over any time period, may each widen and narrow many times, especially at high speed. The race eccentricity is compensated for by the ability of each roller 12 to move rapidly up and down cam ramp 18 as its wedging pocket narrows and expands, generally referred to as roller travel. The energizing spring continually expands and contracts following the roller 12 as it so moves, and keeping it at ready position. A comparison of FIGS. 1 and 2 illustrates roller travel.
The forces that act on roller 12 during overrun, other than external roller disturbing forces, are those induced by the spring 30 and the manner in which it forces its roller 12 into the pathway 14 and the cam ramp 18. So long as roller 12 is kept in contact with with the pathway 14 and its respective cam ramp 18 by its spring 30, it will be maintained generally parallel to the race axis, its ideal orientation, regardless of its position on the cam ramp. The orientation of spring 30, however, will not be as ideally determined. The orientation of spring 30 is best considered in terms of its line of force, shown by dotted lines drawn between and perpendicular to both the center axis of roller 12 and the surface from which spring 30 pushes, that is, the surface of cross bar 28 that faces roller 12. The ideal or optimal line of force of spring 30 would be one which was directed more toward the cam ramp 18, rather than toward the pathway 14. This is because of the dynamic effects on the roller 12 at high speed overrun. The traction of the rapidly relatively rotating pathway 14 on roller 12, even if small in terms of percentage, can still result in a rapid spinning of roller 12, and consequent wear against cam ramp 18. Orienting the spring 30 so as to force the roller 12 more strongly toward cam ramp 18 than pathway 14 can help minimize roller spin. Furthermore, an optimal orientation for spring 30 would also be one in which all the pleats of the spring active portion 36 opened and closed equally and symmetrically about the spring center line, that is, the spring center line and spring line of force would be coincident, or at least close to it. This would minimize spring stress concentrations and oscillations and resist any tendency of the spring 30 to warp out of a straight line, maximizing spring life and stability.
With the conventional spring 30, however, that ideal spring orientation cannot be realized. The line of force of spring 30 will be determined by the position of roller 12 on the cam ramp 18, which changes dynamically, and by the location and orientation of cross bar 28 relative to roller 12. Cross bar 28, and thus the spring mounting fold 32. are fixed relative to cam ramp 18. As seen in FIG. 1, the orientation of cross bar 28 is such that, when roller 12 is located far up cam ramp 18, the spring line of force is directed toward pathway 14, and is offset a good deal from the spring center line, neither of which are optimal spring parameters. While the orientation of cross bar 28 could be initially tilted to direct spring 30 more toward the cam ramp 18 when the roller 12 was in the FIG. 1 position, to do so would threaten the spring operation when the journal block 24 was tight between the races 16 and 20, and the roller 12 was consequently located farther down cam ramp 18. Then, the roller 12 would have a tendency to move under the spring front loop, which could cause the entire spring 30 to pop up into the pathway 14 and lose contact with roller 12. This tendency of roller 12 to dive under spring 30 is worsened by the fact that external roller disturbing forces can actually cause roller 12 to move even farther down cam ramp 18, even out of contact with pathway 14, which is generally referred to as roller pop out, and shown in FIG. 3. It is not feasible to make spring 30 strong enough to resist roller pop out, as that would only worsen pathway traction. So, at no point is the line of force of conventional spring 30 optimal, either in terms of its direction or in terms of being close to the center line of the spring 30. While clutches like clutch 10 certainly work, their operation is not optimized.
SUMMARY OF THE INVENTION
The invention provides a roller clutch which is similar to the conventional one described above in terms of size, cage construction, and rollers, and which is installed between identical races. However, the energizing springs are able to self align, and thus operate on, and maintain themselves on, an optimal line of force.
The energizing spring of the invention, just as with conventional springs, has a roller engaging front contact portion and a substantially straight line active portion. The base of the spring is not fixed, however, but is allowed to pivot relative to the cage as the roller moves up and down the cam ramp and the spring follows the roller. Consequently, the angle of the active spring portion can change in response to roller travel, allowing the spring to self align. Specifically, in the preferred embodiment disclosed, the energizing spring is the serpentine compression type, and is also symmetrical about its center line, with identical end loops, each of which is sized so as to conform to a roller. Each cage journal block includes a spring mount which, rather than being flat, is partially cylindrical and parallel to a respective roller, with a radius equal to the roller. Each spring may therefore be compressed between a roller and respective spring mount in either direction when the clutch is assembled. The line of force of each spring is optimized as to direction, meaning that it faces more toward the cam ramp than the pathway, to minimize pathway traction on the roller. That general spring orientation can maintain itself as the roller travels, unlike a spring with a fixed base. The spring loop that is pressed against the cylindrical spring mount can slide over it, pivoting, in effect, to allow the spring to rock between the spring mount and the roller. The roller will not dive under the spring as in the conventional case, even in the event of roller pop out. Furthermore, the lne of force of the self aligning spring is optimized as to its location relative to the spring center line, being maintained essentially coincident with the spring center line, so that compression and expansion occurs most efficiently.
It is, therefore, an object of the invention to improve the operation of a roller clutch energizing spring by allowing it to self align along an optimal line of force as the roller travels.
It is another object of the invention to optimize the line of force of the spring by allowing the base of the spring to pivot relative to the cage so that the angle of the active portion of the spring can change in response to roller travel.
It is yet another object of the invention to provide cylindrical spring mounts parallel to the rollers and of similar radius, and to provide symmetrical springs with roller conforming end loops, so that the springs can be compressed in either direction between the rollers and respective spring mounts, and will self align so as to maintain a line of force with optimal direction and optimal location relative to the spring center line.
DESCRIPTION OF THE PREFERRED EMBODIMENT
These and other objects and features of the invention will appear from the following written description, and from the drawings, in which:
FIGS. 1 through 3 show the prior art roller clutch already described above;
FIGS. 4 through 6 show a preferred embodiment of the invention, with FIG. 4 showing a roller positioned at a far point up its respective cam ramp;
FIG. 5 shows the roller farther down the cam ramp;
FIG. 6 shows a potential roller pop out position.
Referring first to FIG. 4, the preferred embodiment of the invention, indicated generally at 38, has several identical components, and is used between identical clutch races, as the conventional clutch 10 described above. These components are given the same number with a prime, and are not described again. The journal blocks and energizing springs are different, however. Journal block 40 is molded on one side with an inset spring mount 42 that is cylindrical and has a radius equal to roller 12', with an axis that is parallel to the axis of both roller 12' and cage 38. Spring mount 42 is bounded above by an overhang 44, below by a thin slot 46, and on one side by a wall 48.
Still referring to FIG. 4, energizing spring 50 is the serpentine compression type, and has identical end loops 52, each of which has a radius equal to that of roller 12' and a width slightly less than spring mount 42. The central active portion of spring 50 consists of a series of identical V folds 54. Spring 50 is thus symmetrical about its center line. Spring 50 fits between spring mount 42 and roller 12', with its front end loop 52 pressed against roller 12' and the back end loop 52 pressed against spring mount 42. The length of spring 50 is chosen such that it will fit always be under some compression, at least enough to provide the necessary energizing force, and also enough to hold roller 12' against the opposite side of the adjacent journal block 40 during shipping, if desired. Since spring 50 does not sit against a flat surface, its line of force is determined between, and perpendicular to both, the center axis of roller 12', and the center axis of the cylindrical spring mount 42. The axis of spring mount 42 is positioned above the axis of roller 12' so that the direction of the spring line of force is optimal in terms of direction. That is, the line of force is directed toward the cam ramp 18', so as to minimize roller traction. Furthermore, the spring line of force is optimal in that the spring 50 is seated between roller 12' and spring mount 42 with its center line and the spring line of force essentially coincident. If this orientation could be maintained with roller travel, then spring 50 would expand and contract symmetrically about its center line, which would minimize stress concentrations and warping. The invention does allow that optimal spring orientation to be substantially maintained, as will be described next.
Comparing FIGS. 4 to 5 and 6, it will be seen that as roller 12' moves down cam ramp 18', spring 50 rocks downwardly with it, as front spring loop 52 slides over the surface of roller 12' and back spring loop 52 slides down over the surface of spring mount 42. The back end loop 52 can slide up and down freely on the outer surface of spring mount 42, given their matching curvatures, but will be limited and confined between overhang 44 and slot 46. In effect, the back spring loop 52 pivots about the center axis of spring mount 42, which allows the angle of the active portion of the spring to change in response to the travel of roller 12'. The center axis of spring mount 42 is always above the center axis of roller 12' at all roller positions, so the general direction of the line of force of spring 50 remains toward camp ramp 18'. Furthermore, because of the symmetrical configuration of spring 50 and the conformation of its identical end loops 52 to the spring mount 42 and the roller 12', the spring 50 can shift between the roller 12' and spring mount 42 as they move relative to one another, rocking and sliding to maintain its center line and its line of force essentially coincident. This continual self alignment of spring 50 allows for the most efficient and stress free expansion and contraction of the active V folds 54, and assures that the roller 12' will compress the spring 50 straight back into the spring mount 42, even at roller pop out. This avoids the potential for squeezing spring 50 up and out of contact with roller 12', as with a conventional spring. Journal block 40 is no more expensive to mold than conventional journal block 24. Spring 50 is, if anything, easier to manufacture than conventional spring 30, and is easier to install, given its total symmetry.
Variations of the preferred embodiment may be made within the spirit of the invention. The energizing spring need not be confined to a compression spring. A tension spring that pulled the roller up the cam ramp, rather than pushed the roller up the cam ramp, could also be joined to the clutch cage with a pivotal connection, giving a similar self alignment. Other types of pivotal spring base to cage connections could be used that would allow the angle of the active portion of the spring to change in response to roller movement so as to maintain a desired orientation of the spring line of force. The cylindrical spring mount 42 is a very advantageous way of providing an effective pivot, however. The advantage of the cylindrical spring mount becomes even greater when its radius is made the same as the roller 12', since it allows for the identical spring loops 52. However, the spring mount 42 need not absolutely be of a radius equal to roller 12' just to obtain the pivoting action. The spring need not be made symmetrical just to pivot, but making it so also achieves the efficient and stress free spring operation that results from having the spring center line and spring line of force coincident. Therefore, it will be understood that the invention is not intended to be limited to just the preferred embodiment disclosed. | A roller clutch has springs which, rather than being fixed to the cage, are pivotally attached to the cage so that they can pivot and change the angle of the spring active portion in response to roller travel, thereby self aligning along an optimal line of force. | 5 |
This application is a continuation of application Ser. No. 08/076,367, filed Jun. 14, 1993, now U.S. Pat. No. 5,527,205, which in turn is a continuation of application Ser. No. 07/787,945 filed Nov. 5, 1991 and now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a method of fabricating an endodontic instrument adapted for use in performing root canal therapy on teeth, and which is characterized by high flexibility and high resistance to torsional breakage.
Root canal therapy is a well-known procedure wherein the crown of a diseased tooth is opened so as to permit the canal to be cleaned and then filled. More particularly, a series of very delicate, flexible, finger-held instruments or files are used to clean out and shape the root canal, and each file is manually rotated and reciprocated in the canal by the dentist. Files of increasingly larger diameter are used in sequence, to achieve the desired cleaning and shaping. When the canal is thus prepared, it is solidly filled with a filling material, which typically comprises a waxy, rubbery compound known as gutta percha. In one procedure, the gutta percha is positioned on an instrument called a compactor, and the coated compactor is inserted into the prepared canal and rotated and reciprocated to compact the gutta percha therein. The dentist thereafter fills the tooth above the gutta percha with a protective cement, and lastly, a crown is fitted to the tooth.
Endodontic instruments of the described type are conventionally fabricated by permanently twisting a stainless steel rod of triangular or square cross section. The apices of the triangular or square cross section thus form cutting edges which spiral along the length of the instrument. More recently, such instruments have been produced by a machining process, and wherein a cylindrical rod of stainless steel is moved past a rotating grinding wheel, and while the rod is slowly rotated about its axis so as to impart a desired helical configuration to the ground surface and form a spiral flute on the surface. The rod is thereafter indexed and again moved past the wheel, and these steps are repeated as many times as are necessary to form the rod into a triangular or square cross section. By appropriate control of the process, helical lands may be formed between the spiral flutes as illustrated in U.S. Pat. No. 4,871,312 to Heath.
It is well-known by clinicians that inadvertent errors can occasionally arise during root canal therapy as described above. These errors can include the formation of a ledge in the wall of the canal, the perforation of the canal, and a separation or fracture of the instrument. Many of these errors which occur during the therapy of a canal have a common genesis, i.e. the basic stiffness of the stainless steel instruments, particularly with the respect to the instruments of larger size. Efforts have been made to improve the flexibility of stainless steel instruments based upon different cross sectional shapes, but without significant success.
Recently, a series of comparative tests of endodontic instruments made of nickel-titanium (Nitinol) alloy and stainless steel were conducted. The results of the tests were published in an article entitled "An Initial Investigation of the Bending and the Torsional Properties of Nitinol Root Canal Files", Journal of Endodontics, Volume 14, No. 7, July 1988, at pages 346-351.
The Nitinol instruments involved in the above tests were machined in accordance with the procedure and operating parameters conventionally used in the machining of stainless steel endodontic instruments. More particularly, this standard procedure involves the following parameters:
1. Feed Rate
The rod from which the instrument is to be formed is moved axially past a rotating grinding wheel at a feed rate of about ten inches per minute. The rod is slowly rotated about its axis as it is axially advanced so as to impart a helical configuration to the ground surface.
2. Depth of Cut
The depth of each cut is sufficient to remove all of the material on a given surface without over grinding a previously ground surface. For example, in the case of an instrument triangular cross-section, the rod is moved past the wheel three times, once for each surface, with about 25 percent of the diameter being removed on each cut.
3. Speed of Wheel
An aluminum oxide grinding wheel is provided which is rotated at a surface speed of about 6000 feet per minute, and the wheel has a grit size of about 220.
The above tests demonstrated that the Nitinol instruments produced by the described machining process exhibited superior flexibility and torsional properties as compared to stainless steel instruments, but the cutting edges of the instruments exhibited heavily deformed metal deposits, which rendered the instruments generally unsatisfactory for use.
It is accordingly an object of the present invention to provide a method of fabricating an endodontic instrument which is characterized by high flexibility and high resistance to torsional breakage.
It is another object of the present invention to provide a method of efficiently fabricating an endodontic instrument which is composed of a titanium alloy, such as a nickel-titanium alloy, and which exhibits high flexibility and high resistance to torsional breakage, and which is also characterized by sharp cutting edges.
SUMMARY OF THE INVENTION
The above and other objects and advantages of the present invention are achieved in the embodiments illustrated herein by the discovery that when an endodontic instrument of titanium alloy is machined under certain specific operating parameters, a totally satisfactory instrument, having high flexibility, high resistance to torsion breakage, and sharp cutting edges, may be produced. The specific operating parameters are not suggested by the known procedure for machining stainless steel instruments as summarized above, and indeed, the parameters which are effective in producing a satisfactory instrument are directly contrary to accepted practices for machining titanium alloys as presented in authoritative literature, note for example the brochure entitled "RMI Titanium", published by RMI Company of Niles, Ohio.
More particularly, the present invention involves the steps of (a) providing a cylindrical rod of metallic material which is composed of at least about 40% titanium and which has a diameter less than about 0.06 inches, and (b) axially moving the rod past a rotating grinding wheel at a feed rate of not more than about 5 inches per minute, while rotating the rod about its axis, and so that the wheel removes at least about 25% of the diameter of the rod at the point of maximum removal and forms a helical surface on the rod. The grinding wheel is rotated at a relatively slow surface speed of not more than about 3000 feet per minute, and preferably not more than about 2200 feet per minute. Also, the grinding wheel has a relatively fine grit size which is greater than about 200 grit, and preferably greater than about 220 grit. In the preferred embodiment, the rod is composed of an alloy comprising at least about 40% titanium and about 50% nickel.
It is often preferred to form the rod into a triangular or square cross sectional configuration, and in such embodiments, the rod is rotatably indexed about a rotational axis of not more than 180 degrees, and specifically either 120 degrees or 90 degrees, and step (b) is repeated so as to form a second helical surface on the rod. The indexing and grinding steps are again repeated as many times as are necessary to form the desired number of sides on the instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects and advantages of the present invention having been stated, others will appear as the description proceeds, when taken in conjunction with the accompanying drawings, in which
FIG. 1 is a cross sectional view of a tooth have two roots, with an endodontic instrument manufactured in accordance with the present invention being positioned in one of the roots;
FIG. 2 is an enlarged perspective view of the lower portion of the instrument shown in FIG. 1;
FIG. 3 is a transverse sectional view taken substantially along the line 3--3 of FIG. 2;
FIG. 4 is a view similar to FIG. 2, but illustrating a second embodiment of the instrument;
FIG. 5 is a transverse sectional view taken substantially along the line 5--5 of FIG. 4;
FIG. 6 is a schematic side elevation view of a machining apparatus which is adapted to fabricate endodontic instruments in accordance with the present invention; and
FIG. 7 is a top plan view of the apparatus shown in FIG. 6, and illustrating certain of the steps of the fabrication process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring more particularly to FIGS. 1-3, an endodontic instrument 10 is illustrated which comprises a shank 12 which is composed of a titanium alloy as further described below. The shank 12 typically has a length of about 30 mm (1.2 inches), and it includes an outer or proximate end which mounts a conventional handle 14. The portion of the shank immediately below the handle is cylindrical and has a diameter of between about 0.5 and 1.6 mm (0.02 and 0.07 inches), and this shank portion includes calibrated depth markings 15 of conventional design. The shank further includes an opposite distal or pilot end 16, and a working length 18 is defined adjacent the pilot end 16. The working length may be cylindrical as illustrated, or it may be slightly tapered toward the pilot end 16 at an included angle of about one degree. The working length 18 may have a length of about 2 mm (0.08 inches) up to the full length of the shank 12, i.e. about 30 mm (1.2 inches). However, in the illustrated embodiment, the working length 18 has a length sufficient to extend substantially the full depth of a tooth root canal as illustrated in FIG. 1, which is about 16 mm (0.63 inches). Also, the cross sectional configuration of the working length 18 is triangular and is composed of three linear surfaces 19, as best seen in FIG. 3, and so that the apices of the triangle form cutting edges.
FIGS. 4-5 illustrate a second embodiment of an endodontic instrument 10' which may be fabricated in accordance with the present invention. In this embodiment, the outer peripheral surface of the working length 18' is tapered at an included angle of about one degree, and the working length 18' includes two continuous helical flutes 21, 22 formed in the peripheral surface. The flutes have an arcuate curvature as best seen in FIG. 5, and they have a pitch so as to define helical lands 24 on the outer periphery of the instrument. An instrument of this general construction is further described in U.S. Pat. No. 4,871,312 to Heath, and pending application Ser. No. 07/679,628, filed Apr. 3, 1991.
FIGS. 6 and 7 schematically illustrate a machining apparatus for practicing the method of the present invention. As will be further described below, the method involves a unique machining process which has been found to efficiently produce endodontic instruments of the type described, from a rod 30 composed of titanium alloy. Such alloys typically have a titanium content of at least about 40 percent. Nickel-titanium alloys are preferred, which typically consist of about 40 percent titanium and about 50 percent nickel. In one preferred specific embodiment, the alloy consists of 44 percent titanium and 56 percent nickel and no appreciable amount of other ingredients which could adversely effect the purity required for endodontic instruments.
The rod 30 from which the instrument is to be fabricated is conventionally supplied from the producer in a selected diameter, which closely conforms to the diameter of the instrument being produced. In this regard, endodontic instruments are sized in accordance with established standards, which range from a diameter at the pilot end 16 of 1.4 mm (0.062 inches-size 140) to a diameter at the pilot end 16 of 0.06 mm (0.0024 inches-size 06).
In accordance with the illustrated embodiment of the present invention, the continuous rod 30 is positioned to extend through an axial feed block 32 and an indexing block 34 of conventional well-known construction. A work holding fixture 36 is positioned to support the forward end of the rod 30 adjacent the periphery of a rotating grinding wheel 38. The two blocks 32, 34 are then advanced so that the rod 30 is axially moved past the rotating grinding wheel 36 at a slow feed rate of between about 3 to 8 inches per minute, and preferably not more than about 5 inches per minute. Concurrently with this axial movement, the indexing block 34 serves to slowly rotate the rod 30 about its axis at a controlled speed, which causes the ground surface 19 to assume a helical configuration as described above with respect to FIGS. 2 and 3.
The rod preferably moves past the wheel only once for each ground surface 19, and thus the rod is positioned with respect to the wheel 38 such that the full depth of the cut is removed in a single pass. As best seen in FIG. 3, the wheel preferably removes at least about 25 percent of the diameter of the rod at the point of maximum removal, which is along a diameter which extends perpendicular to the surface 19 being formed.
As a further aspect of the present invention, the grinding wheel 38 is rotated at a relatively slow surface speed of not more than about 3000 feet per minute, and preferably not more than about 2200 feet per minute. Further, the wheel 38 is composed of a relatively fine grit, which is greater than about 200 and preferably about 220 grit. A wheel of the above grit size and which is fabricated from silicon carbide has been found to be very satisfactory.
To produce an instrument of the construction illustrated in FIGS. 1-3, the grinding wheel 38 is oriented to rotate about an axis generally parallel to the axis of the advancing rod 30, and the wheel 38 thus forms a generally flat surface 19. Also, by reason of the slow rotation of the rod about its axis, this flat surface assumes a helical configuration. Where the instrument is to have a tapered working length, the axis of the index block 34 is slightly inclined with respect to the rotational axis of the wheel 38, so as to provide a controlled and variable depth of cut along the working length.
When the rod 30 has advanced past the rotating wheel 38 a distance sufficient to form the first surface 19 along the desired working length on the instrument, the table 39 supporting the feed block 32, the index block 34, and the fixture 36 is moved laterally, then axially rearwardly, and then laterally back to its original position as illustrated schematically in FIG. 7. Concurrently, the rod 30 is rotatably indexed about its axis. The angular extent of this rod indexing will depend upon the number of surfaces 19 desired on the finished instrument, and where three surfaces are to be formed as seen in FIG. 3, the rod is indexed 120 degrees. The rod is then again axially advanced while being slowly rotated, and so as to form the second surface 19. The table 39 is then again moved laterally and rearwardly in the manner described above, and the rod 30 is rotatably indexed another 120 degrees. The grinding process is then repeated to form the third surface 19 of the instrument. The rod 30 may then be severed by conventional techniques, such as by axially advancing the rod and then moving the grinding wheel laterally through the rod. The severed rod is then further processed in a conventional manner to form the completed instrument as illustrated for example in FIG. 1.
As a modification of the illustrated process, the rod 30 may be initially severed into appropriate lengths, and each length may be separately mounted in a collet at the forward end of the indexing block 34, and then machined in the manner described above.
The process as described above has been found to produce instruments of consistently high quality, and at commercially acceptable production rates. Of particular significance, the process results in the formation of cutting edges at the apices of the triangular cross section, which are sharp, and substantially free of burrs and rolled edges which characterized the early instruments of titanium alloys as described above.
While an instrument of triangular cross section is illustrated in FIGS. 1-3, it will be understood that other configurations are possible. For example, the instrument could have four sides which form a square in cross section. In the embodiment of FIGS. 4-5, the working length 18' of the instrument is tapered and is composed of two helical flutes 21, 22 of arcuate configuration. To fabricate this embodiment, substantially the same procedure as described above is followed. However, the taper of the working length 18' is preferably initially formed on a separate grinding machine, and the tapered blank is then mounted on a machine as shown in FIG. 6, and the axis of the wheel 38 is oriented so that the wheel lies in a plane which follows the desired helical configuration of the flutes 21, 22. Also, the outer periphery of the wheel is curved in cross section as opposed to being flat, and so as to form the desired arcuate configuration of the flutes 21, 22. Since the instrument as illustrated has two flutes, the rod is indexed 180° between the two machining operations.
In the drawings and specification, there has been set forth preferred embodiments of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. | A method of fabricating an endodontic instrument by a machining operation is disclosed, and wherein a wire-like rod composed of a titanium alloy is advanced past a rotating grinding wheel at a relatively slow feed rate, with a sufficient depth of cut to remove all of the material on a given surface without over grinding a previously ground surface, and with the grinding wheel rotating at a relatively slow surface speed. The disclosed method is able to efficiently produce endodontic instruments having a high degree of flexibility, high resistance to torsional breakage, and with sharp cutting edges along the working length. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a mouse having a wheel mechanism, and more particularly to a mouse having a tilt wheel encoding mechanism.
BACKGROUND OF THE INVENTION
[0002] An input device such as a mouse or a keyboard has been widely employed in a computer system for scrolling images shown on the display screen upwardly and downwardly. For example, by rotating a scroll wheel of the input device forwardly or backwardly, a specified control signal is generated to control the scrolling operations of web pages. In addition to the vertical scroll movement, it is important to achieve the horizontal scroll movement. For example, since the texts or graphs shown in the graphic-based window of the display screen usually fail to be fully browsed, the horizontal scroll movement is required to move the web page or the document in the left or right direction so as to display the desired image as required.
[0003] For facilitating a user to perform the horizontal scroll movement of the web pages shown on the display screen by operating the scroll wheel, a tilt scroll wheel module capable of being tilted leftwards or rightwards is developed. Such tilt scroll wheel module is applicable to an input device such as a mouse or a keyboard. Referring to FIG. 1 , a schematic outward view of a mouse having a tilt scroll wheel module is illustrated. The tilt scroll wheel module 11 of the mouse 1 is positioned within an opening 101 of the main body 10 of the mouse 1 , and the scroll wheel 12 is partially protruded from the outer surface of the main body 10 such that the tilt scroll wheel module 11 can be manipulated by a user. The scroll wheel 12 of the tilt scroll wheel module 11 can be rotated forwardly (as shown in the arrow F) or backwardly (as shown in the arrow B) to generate a control signal, thereby scrolling the image shown on the display screen upwardly and downwardly. Furthermore, the scroll wheel 12 can be pressed down (as shown in the arrow D), tilted toward the left side (as shown in the arrow L) or tilted toward the right side (as shown in the arrow R) so as to generate three other control signals.
[0004] Referring to FIG. 2 , a schematic perspective view of the tilt scroll wheel module used in the tilt scroll wheel module of FIG. 1 is illustrated. The tilt scroll wheel module 11 principally comprises a scroll wheel 12 , a rotating shaft 13 , a carrier member 14 and a supporting member 15 . The supporting member 15 has a receptacle 151 at the top side thereof. In addition, three switch units 16 A, 16 B and 16 C are arranged under the bilateral sides of the carrier member 14 and under the rear end of the carrier member 14 , respectively. The rotating shaft 13 is supported on a notch structure 141 of the carrier member 14 , so that the scroll wheel 12 is rotatable along the rotating shaft 13 .
[0005] Please refer to FIG. 2 again. The tilt scroll wheel module 11 further comprises lateral wing structures 142 A and 142 B at bilateral sides of the carrier member 14 and above the switch units 16 A and 16 B, respectively. In addition, the front and rear ends of the carrier member 14 are formed as protrusion rods 143 A and 143 B. The protrusion rod 143 A is movably supported on the receptacle 151 of the supporting member 15 . Whereas, the protrusion rod 143 B is placed on the top surface of the switch unit 16 C. In a case that the scroll wheel 12 is tilted toward the left or right side, the receptacle 151 of the supporting member 15 and the top surface of the switch unit 16 C are used as the fulcrum portions such that the carrier member 14 is movable in the left or right direction. Meanwhile, the lateral wing structure 142 A or 142 B will touch and trigger the switch unit 16 A or 16 B. In addition, in a case that the scroll wheel 12 is pressed down, the receptacle 151 of the supporting member 15 is served as the fulcrum portion such that the protrusion rod 143 B is moved downwardly to trigger the switch unit 16 C.
[0006] The tilt scroll wheel module 11 mentioned above, however, still has some problems. For example, in the case that the scroll wheel 12 is not enabled, the protrusion rod 143 B of the carrier member 14 is slightly in contact with the top surface of the switch unit 16 C but the switch unit 16 C is not triggered. If the scroll wheel 12 is pressed down, the switch unit 16 C may be triggered by the protrusion rod 143 B of the carrier member 14 . Unfortunately, the depressing force applied onto the scroll wheel 12 is likely to improperly swing toward the left or right side due to a slippery hand or other reasons. Under this circumstance, the lateral wing structure 142 A or 142 B is likely to touch and trigger the switch unit 16 A or 16 B. As a consequence, the mouse 1 is suffered from an erroneous operation such as interruption of a current control signal or generation of an unanticipated control signal.
[0007] For solving the above problems, an input device with a tilt scroll wheel module was disclosed in a co-pending Taiwanese Patent Application No. 95100875, which was filed by the same assignee of the present application on Jan. 10, 2006, and the contents of which are hereby incorporated by reference.
[0008] Referring to FIG. 3 , a schematic perspective view of the tilt scroll wheel module disclosed in Taiwanese Patent Application No. 95100875 is illustrated. In accordance with a feature of FIG. 3 , the tilt scroll wheel module 21 further includes two confining members 27 and 28 for confining the carrier member 24 in position. The confining members 27 and 28 have complementary shapes. Due to the complementary shapes, the confining member 27 is shifted downwardly to be engaged with the confining member 28 while the scroll wheel 22 is pressed down to trigger the switch unit 26 C. Therefore, the carrier member 24 is confined in position so as to avoid improperly swinging the carrier member 24 toward the left or right side or otherwise allow for tiny swing of the carrier member 24 . Under this circumstance, the carrier member 24 will no longer trigger the switch unit 26 A or 26 B while the scroll wheel 22 is pressed down to trigger the switch unit 26 C. Until the depressing force applied onto the scroll wheel 22 is eliminated, the scroll wheel 22 is moved upwardly and returns to its original shape due to a restoring force generated from the compressed switch unit 26 C. Meanwhile, the confining member 27 is disengaged from the confining member 28 , so that the carrier member 24 can be tilted toward the left or right side as required.
[0009] The tilt scroll wheel module 21 of FIG. 3 is effective for solving the problem occurred in the tilt scroll wheel module 11 of FIG. 2 . However, there are still some drawbacks. For example, since two switch units are arranged at the bilateral sides of the scroll wheel and associated triggering components are required to trigger these two switch units, the volume thereof occupies much working space within the mouse and is adverse to space utilization. In addition, too many components increase the assembling time of mounting the switch units and the triggering components onto the proper positions of the mouse.
[0010] Therefore, there is a need of providing a mouse having a simplified tilt wheel encoding mechanism.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to provide a mouse having a tilt wheel encoding mechanism by using a multi-direction switch unit, so that the tilt wheel encoding mechanism is simple in the structure and easily assembled.
[0012] In accordance with an aspect of the present invention, there is provides a mouse device. The mouse device includes a main body and a tilt wheel encoding mechanism. The main body includes a base. The tilt wheel encoding mechanism includes a scroll wheel, a wheel carrier and a multi-direction switch unit. The scroll wheel is operable by a user. The wheel carrier includes a first end, a second end, a triggering arm adjacent to the second end, a first support part arranged on the base for supporting the first end, a second support part arranged on the base for supporting the second end, and a receptacle for receiving the scroll wheel therein such that the scroll wheel is rotatable in the receptacle. The triggering arm further includes an indentation. The multi-direction switch unit is disposed under the triggering arm and includes a triggering button, which is embedded into the indentation.
[0013] In an embodiment, the wheel carrier further includes two sidewalls cooperatively defining a receptacle for receiving the scroll wheel therein.
[0014] In an embodiment, the wheel carrier further includes a wheel carrier axle protruded from the first end thereof, and the first support part is a support plate having a notch for receiving the wheel carrier axle therein.
[0015] In an embodiment, the wheel carrier further includes a vertical support plate at the second end thereof, and the second support part includes a confining recess for receiving the vertical support plate therein.
[0016] Preferably, the multi-direction switch unit is a three-direction switch.
[0017] Preferably, the multi-direction switch unit is a five-direction switch.
[0018] The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic outward view of a mouse having a tilt scroll wheel module according to prior art;
[0020] FIG. 2 is a schematic perspective view of the tilt scroll wheel module of the mouse in FIG. 1 ;
[0021] FIG. 3 is a schematic perspective view of the tilt scroll wheel module disclosed in Taiwanese Patent Application No. 95100875;
[0022] FIG. 4 is a schematic exploded view of a mouse having a tilt wheel encoding mechanism according to a preferred embodiment of the present invention;
[0023] FIG. 5A is a schematic perspective view of a three-direction switch;
[0024] FIG. 5B is a schematic perspective view a five-direction switch; and
[0025] FIG. 6 is a schematic assembled view of the tilt wheel encoding mechanism of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] Referring to FIG. 4 , a schematic exploded view of a mouse having a tilt wheel encoding mechanism according to a preferred embodiment of the present invention is illustrated.
[0027] The mouse of FIG. 4 principally includes a base 200 , a scroll wheel 201 , a wheel carrier 202 , a first support part 203 , a second support part 204 and a multi-direction switch unit 205 . The wheel carrier 202 includes a first sidewall 202 A, a second sidewall 202 B, a first end 2021 , a second end 2022 and a triggering arm 2023 . The triggering arm 2023 has an indentation 20231 , as is shown in FIG. 6 .
[0028] Please refer to FIG. 4 again. A wheel carrier axle 202 C is protruded from the first end 2021 of the wheel carrier 202 . The first support part 203 is a support plate having a notch 203 A. The wheel carrier 202 further includes a vertical support plate 202 D at the second end 2022 . The second support part 204 is a confining recess formed in the base 200 .
[0029] Hereinafter, the structure and the operation of the encoding mechanism will be illustrated as follows.
[0030] First of all, the scroll wheel 201 is partially received within a receptacle 202 E between the first sidewall 202 A and the second sidewall 202 B. Then, the wheel carrier axle 202 C at the first end 2021 of the wheel carrier 202 is received in the notch 203 A of the first support part 203 , and the vertical support plate 202 D at the second end 2022 of the wheel carrier 202 is received in the confining recess 204 . In addition, an encoder receiving structure 202 B 1 is extended from a second sidewall 202 B 1 of the wheel carrier 202 for accommodating a mechanical encoder 202 B 2 therein.
[0031] The multi-direction switch unit 205 is arranged on a circuit board (not shown) and includes a triggering button 205 A. The triggering button 205 A is received within the indentation 20231 of the triggering arm 2023 .
[0032] Referring to FIGS. 5A and 5B , two examples of the multi-direction switch unit 205 are schematically illustrated. In FIG. 5A , the multi-direction switch unit 205 is a three-direction switch. In FIG. 5B , the multi-direction switch unit 206 is a five-direction switch. As shown in FIG. 5A , three triggering signals are generated when the triggering button 205 A of the three-direction switch 205 is triggered. That is, in response to external forces exerting on the triggering button 205 A as shown in the arrows R 1 , R 2 and R 3 , first, second and third triggering signals are respectively generated. Until the external force applied onto the triggering button 205 A is eliminated, the triggering button 205 A returns to its original position. As previously described, the conventional switch unit is triggered to generate a triggering signal. In contrast, a single three-direction switch 205 can be triggered to generate three triggering signals. Likewise, as shown in FIG. 5B , five triggering signals are generated when the triggering button 206 A of the five-directional switch 206 is triggered. That is, in response to external forces exerting on the triggering button 206 A as shown in the arrows R 1 , R 2 , R 3 , R 4 and R 5 , five triggering signals are respectively generated.
[0033] Referring to FIG. 6 , a schematic assembled view of the mouse shown in FIG. 4 is illustrated. Hereinafter, the structure and the operations of the tilt wheel encoding mechanism will be illustrated with reference to FIG. 4 , and FIG. 6 .
[0034] First of all, the scroll wheel 201 is partially received within the receptacle 202 E between the first sidewall 202 A and the second sidewall 202 B, and a portion of the scroll wheel 201 is protruded from the outer surface of the main body such that the scroll wheel 201 can be manipulated by a user.
[0035] When the scroll wheel 201 is rotated, the mechanical encoder 202 B 2 within the encoder receiving structure 202 B 1 will generate a third axle signal to control image scrolling. When the scroll wheel 201 is pressed down to have the wheel carrier 202 move downwardly, the triggering arm 2023 of the wheel carrier 202 will touch the triggering button 205 A of the three-directional switch 205 . Meanwhile, the triggering button 205 A is triggered in response to the external force along the direction R 1 , thereby generating the fist triggering signal. When the scroll wheel 201 is tilted toward the left side in the direction R 2 , the wheel carrier 202 is swung toward the left side in the direction R 2 in a swing radius D equivalent to the distance between the confining recess 204 and the triggering arm 2023 and with the confining recess 204 serving as a fulcrum. Meanwhile, the triggering button 205 A is also tilted toward the left side in the direction R 2 to generate the second triggering signal because the triggering button 205 A of the multi-direction switch unit 205 is embedded into the indentation 20231 of the triggering arm 2023 . Similarly, when the scroll wheel 201 is tilted toward the right side in the direction R 3 , the triggering button 205 A is also tilted toward the right side in the direction R 3 to generate the third triggering signal.
[0036] The magnitude of the swing radius D indicates the degree of tilting the wheel carrier 202 to trigger the multi-direction switch unit 205 . For example, if the encoding mechanism has a larger swing radius D 1 (i.e. D 1 >D), a smaller degree of tilting the wheel carrier 202 is required to trigger the multi-direction switch unit 205 .
[0037] Likewise, by operating the scroll wheel 201 , five triggering signals are generated when the triggering button 206 A of the five-direction switch 206 is triggered.
[0038] From the above description, the tilt wheel encoding mechanism according to the present invention has functions similar to the conventional tilt scroll wheel module by using a single multi-direction switch unit. Moreover, the problems of using three switch units will be solved so as to avoid an erroneous operation.
[0039] While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. | The present invention relates to a mouse device having a tilt wheel encoding mechanism. The tilt wheel encoding mechanism includes a scroll wheel, a wheel carrier and a multi-direction switch unit. The scroll wheel is operable by a user. The wheel carrier has a receptacle for receiving the scroll wheel therein such that the scroll wheel is rotatable in the receptacle. By using the multi-direction switch unit to generate plural triggering signals, this encoding mechanism is simplified. | 6 |
The invention described herein may be manufactured, used, and licensed by or for the U.S. Government for governmental purposes without the payment to me of any royalty thereon.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to weapon sights and more specifically to a flexible weapon sight which springs up to a preset position from a stored position.
2. Description of the Prior Art
Weapon sights of the prior art have been made generally of durable, metal materials for multiple use in a wide range of diverse environments. The relationship between the range adjusting knob and the elevated sighting element has involved gear and friction drives. With the advent of single use weapons, it has become imperative to have inexpensive sights which (when deployed) will assume a preset battle range condition for immediate firing as well as having the ability to be quickly adjusted to other ranges if they are known.
A mechanically simple sight is illustrated in U.S. Pat. No. 45,333 as a spring B which is manually pushed along the horizontal plane to adjust the vertical displacement of a sight notch F. Since this patent does not disclose a housing, the presetting of this specific sight to a preset battle sight would have the sight notch F always in an elevated position above the barrel. This is a major problem since the sight would be exposed to damage during carrying and storing. It cannot be stressed enough how important it is to have a sight which is automatically deployed to a specific range so as to be immediately available for instantaneous aiming and firing. Similarly, the user of the weapon to which the sight of U.S. Pat. No. 45,333 is attached would have to be looking down on the top of the barrel in order to note the specific range adjustments at H. This also slows down the ability of the user to fire the weapon.
Though other sights of the prior art have included housings, these housings and the sights encompassed therein have not been inexpensively manufactured. Thus, there exists a need for an inexpensive sight for a throw-away or onetime use weapon which is automatically deployed to a fixed battle site range.
SUMMARY OF THE INVENTION
The present invention provides an economical and inexpensive battle sight using a resilient sight bar which is stored in a generally horizontal position below the cover of the housing and automatically springs up to a vertical preset battle range position upon opening or removing the cover. The bar is a single piece of thin metal having a curved transverse cross-section so as to provide rigidity to the light metal bar. A day-night peep is pivotally connected to the top end of the sight bar and the opposite end has a protuberance attached which coacts with the base of the housing to produce audible and tactile indications of specific changes of range. The range adjust knob is attached to the sight bar by a single pin to provide an inexpensive and secure drive between the range adjust knob and the sight bar. A central recess is provided in an interior curved surface of the housing so that the pin rides in the recess during adjustment of the elevation of the sight by the range adjustment knob. A flat is provided on the range adjustment knob to coact with the cover to lock and guarantee the preset battle site range by permitting the cover to close only when the range adjustment knob is at the preset battle site range.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide an inexpensive, retractable preset sight for a one-time or disposable weapon.
A further object of the present invention is to provide a resilient sight mechanism which automatically springs to a preset battle site position upon removing the top of the sight casing.
An even further object of the present invention is to provide an inexpensive sight which provides an audible and tactile indication of change of range setting from a preset battle range position.
A still further object of the present invention is a sight having a day-night peep sight where the detent is merely coincidental curved surfaces.
A still further object is to provide a simple mechanism to guarantee the preset battle site range in the stored position.
Other objects, advantages and novel features of the present invention will become apparent from a detailed description of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a preferred embodiment of the weapon sight of the present invention with the side plate of the housing removed;
FIG. 2 is a front cross-sectional elevation taken along lines 2--2 of FIG. 1;
FIG. 3 is a rear elevation taken along lines 3--3 of FIG. 1; and
FIG. 4 is a top partial elevation illustrating the detail of the peep sight.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the weapon sight of the present invention is illustrated in FIGS. 1-4. The sight 10 is mounted to the cylindrical exterior of a disposable weapon 12 having a trigger mechanism 14. Though the weapon 12 is being illustrated as a disposable rocket launcher, it should be noted that the present sight may be mounted on a disposable weapon or any re-usable weapon which requires an inexpensive sight. The sight housing 16 has a slidable cover 18, a bottom 20, front and rear walls 22 and 24, and side walls 26 and 28. The bottom 20 and lateral walls 22, 24 and 26 may be made of a single piece of material such as metal or plastic. The side wall 28 is a single plate of the same material and is attached by fasteners received in holes 30 illustrated in FIG. 1. By providing wall 28 as a separate plate, the sight may be assembled and mounted within the interior of the housing very economically.
The top or cover 18 has a member 32 extending up and away from the plate of cover 18 to provide means by which the cover 18 may be readily moved in the horizontal plane. L-shaped members 34 extend down from cover 18 and ride within recesses or tracts 36 in walls 26 and 28 of the housing. By movably mounting the cover 18 around the exterior of the side walls so as to lie in recesses 36, the cover prevents dust and mud from entering the casing and interfering with the operation of the sight during transporting on the battlefield. As to be explained more fully below, the left (as viewed in FIG. 2) L-shaped member 34 coacts with the range adjustment knob to lock and guarantee that the range adjustment knob is set at the preset battle site range. Although top 18 is shown as mounted exterior to the remainder of the housing, it is evident that the top 18 may be mounted between the walls 26 and 28. The internal mount of cover 18 is not considered as advantageous as exterior mounting of the cover.
In the bottom 20 of the housing is mounted a plate 38 having a plurality of serrated edges 40 extending up therefrom. As will be explained later, the serrated edges 40 are separated by a specific distance which is proportional to a preselected range change which may be, for example, 50 yards of range between serrated edges.
Starting at the bottom and near the rear of bottom 20 and extending up the rear wall 24 of the housing is a surface 42 which is curved around the length and width of the housing. Thus, the transverse cross-section of the curved surface 42 is concave relative to the interior of the housing. A recess 44 is centered and runs substantially the length of curved surface 42 to carry a pin which will be explained hereafter.
The sight includes a sight bar 46 of spring stock metal having a sight aperture 48 in an extended end and a protuberance 50 mounted to the other end. The protuberance 50 extends down to, and coacts with, the serrated edges 40 so as to provide an audible and tactile indication of specific range changes as the sight bar 46 is moved along the curved surface 42. An aperture 52 provided in sight bar 46 receives a pin 54 which connects the sight bar 46 to an internal curved member 56 of the range adjustment means. Pin 54 rides in recess 44 in the curved surface. As will be explained later, the pin provides the single positive connection of the sight bar 46 to the range adjustment means which includes internal curved member 56 and an external range adjustment knob 68. As seen specifically in FIG. 4, the sight bar 46 has a curved transverse cross-section. This curvature of the thin spring metal stock provides rigidity to the extended portion of bar 46 so as to not be effected by wind or other environmental conditions during sighting operations.
Member 56 has a curved surface portion 58 to which pin 54 is connected. The curved surface 58 and the interior curved surface 42 of the housing have substantially the same curvature. Sight bar 46 rides between the two curved surfaces 58 and 42. A rod portion 60 of member 56 has a first end 62 received in a bushing or journel 64 attached to the side wall plate 28 of the housing. The second end of 60 is received in the range adjustment knob 68 which lies exterior and adjacent to wall 26 of the housing. A flat or planar surface 69 is provided on the range adjustment knob 68 adjacent housing wall 26 and L-shaped member 34 of cover 18. The flat surface 69 coacts with L-shaped member 34 to permit the closing of the cover 18 only when the flat surface is parallel to the cover. At this position, the range adjustment knob 68 is set to the battle site range. Thus, the sight is locked at, and guaranteed to be set at, the battle site range. The range adjustment knob 68 may have flat surface 69 machined to correspond to any desired battle site range. As shown in FIG. 3, indicia 70 are placed on range adjustment knob 68 to move relative to a fiducial mark 72 on the rear wall 24 of the housing.
The peep sight of the present invention includes a front plate 74 having a curved surface 76 and a rear plate 78 having a curved surface 80. The sight bar 46 lies between the two curved surfaces 76 and 80. The front sight plate 74 and the rear sight plate 78 are joined to the bar 46 by a pin 82. The front plate 74 has a tapered aperture 84 therein which is larger than the sight aperture 48 in the bar 46. The rear plate 78 has a tapered aperture 86 terminating in a counter-bore aperature 88. The aperture 88 is smaller than the aperture 48 in bar 46. Aperture 88, which may be approximately 2 millimeters in diameter, comprises the daylight peep sight in the position shown in FIGS. 1-4. By rotating rear plate 78 180°, so as to lie in the phantom view as shwon in FIG. 3, the aperture 48 (which may be approximately 6 millimeters in diameter) comprises the nightlight peep sight. Since bar 46 has a curved transverse cross-section, the rear sight plate 78 may be rotated and locked in two positions 180° apart by using merely the relationship of the curvature of bar 46 and of surface 80 of rear sight plate 78. Thus, a detent is provided without any other mechanical elements.
The sight of the present invention is installed at the factory on a disposable weapon 12. The elevation of the sight bar 46 is adjusted so as to assume a battle site elevation by rotation of range adjustment knob 68 until flat surface 69 is parallel to the cover 18. Sight bar 46 is rotated from its extended vertical position to a horizontal position around curved surface 58 of element 56. The cover 18 is slid back over so as to close the top of the housing, lock the range adjustment knob at the battle site range, and retain the extended portion of sight bar 46 in a generally horizontal position. If, for example, the disposable element is a rocker launcher, end caps are placed over the two ends of the rocket launching cylinder 12 and a front sight, separate from the present sight element 10, is also collapsed into a stored position. As noted before, the cover 18 (by extending over the top and around the lateral edges of the housing) provides a dust and mud-free cover. The weapon sight of the present invention as stored may be carried into battlefield conditions.
When it is desired to put the present weapon sight into use, the end caps are taken off the weapon, the front sight is spring-loaded so that the apparatus is automatically operated, and the operator (by pushing on extended element 32) slides the cover 18 forward and sight bar 46, due to its resiliency, springs up into a vertical extended position at a battlefield range height. The operator may then immediately aim through the peep sight and fire. If it is night conditions, the operator merely rotates rear sight element 180° to provide a night sight peep. In either day or night conditions, the operator (if he has time and knowledge of the specific range of the target), may rotate range adjustment knob 68, which has been unlocked by opening cover 18, to change the elevation of sight bar 46 for the specific range. Without wasting time to visually check the specific range, the operator may determine by the number of clicks the change of range from the preset battlefield range and may fire immediately upon hearing or feeling the required number of clicks. This is especially advantageous in dark surroundings.
Thus, it is seen that the objects of the present invention are achieved by the preferred embodiments to provide an inexpensive weapon sight which automatically deploys itself to a fixed battlefield range and provides audible and tactile indication of given changes of range. The simplicity of design reduces the cost of raw materials to make the sight as well as providing a reliable sight. Though the present invention has been described in detail, it is obvious that changes may be made without altering the scope of the invention. I wish it to be understood that I do not desire to be limited to the exact details of the construction shown and described for obvious modifications can be made by a person skilled in the art. | A weapon sight having a peep sight mounted to a flexible, curved transverseross-section bar movable across a curved surface interior to a housing. The flexible bar, which is preset and locked at a fixed range, is stored horizontally below the cover of the housing and assumes a vertical position with the peep sight at the fixed range when the cover is opened. A protuberance from the other end of the bar produces an audible and tactile indication of fixed variations in range. The range adjustment knob drives the bar with a single pin. | 5 |
RELATED U.S. APPLICATION DATA
[0001] This application is a continuation application Ser. No. 12/273,485 filed Nov. 18, 2008 which is a continuation of application Ser. No. 12/015,459, filed on Jan. 16, 2008 which is continuation of application Ser. No. 11/372,254, filed on Mar. 8, 2006 which is a continuation of application Ser. No. 10/857,031, filed on May 28, 2004, which is a continuation of application Ser. No. 09/929,975, filed on Aug. 15, 2001, which is a divisional application of application Ser. No. 09/109,312 filed Jun. 30, 1998, now U.S. Pat. No. 6,308,890, which itself is a divisional application of application Ser. No. 08/802,672 filed Feb. 19, 1997, now U.S. Pat. 5,834,747, which is a Continuation of application Ser. No. 08/334,474 filed Nov. 4, 1994.
BACKGROUND OF THE INVENTION
[0002] The invention relates to the use of devices having information or patterns carried in or on some storage media, examples of which include photographic patterns, keys or the magnetic strip on credit cards. The invention provides for an apparatus and method allowing more than one pattern or set of information to be used with a given type of medium to facilitate use by the holder thereof with a pattern reading device and to reduce the numbers of separate information or pattern media carrying devices which must be used, Other uses and purposes for the present invention will also become known to one skilled in the art from the teachings herein.
FIELD OF THE INVENTION
[0003] The field of the invention includes the storage and use of information or patterns on or in operator usable medium, examples including credit cards, keys, holograms, photographs and the like, by use of various magnetic, electronic, optical and mechanical devices. Such information or patterns may be known, unknown, ordered or random, coherent or incoherent, there being no restriction on the types or nature of information or patterns with which the invention may be used. The operators may be human, animal or otherwise, and may involve different operators of different persons or types at various times.
DESCRIPTION OF THE PRIOR ART
[0004] It is well known to store particular information or patterns such as account numbers, bar codes, security codes, etc. on magnetic and optical storage medium embedded in small, sturdy and relatively inexpensive carriers such as credit cards. FIG. 1 shows for example a prior art credit card diagram having a strip of magnetic material 2 which is embedded in a plastic substrate 1 which magnetic strip carries a pattern of magnetization which is a magnetic representation of information or patterns relating to the credit card. FIG. 1 is shown in graphical form with the top and front edge view of the magnetic strip with a representation of the magnetic flux pattern recorded therein.
OBJECTS AND DISCLOSURE OF THE INVENTION
[0005] The invention described herein provides for a method and apparatus whereby a plurality of sets of patterns or information may be stored and utilized by a user. The invention allows access to numerous accounts, services, features, etc. with just one storage device, thereby eliminating the need to carry, store, remember or retain numerous data storage devices, data sets or patterns. Examples of applications for the present invention include the magnetic pattern information of a plurality of credit cards which may be stored in a single convenient card which a user may carry in order to replace a plurality of individual credit cards, programmable optical patterns such as bar codes or photographic patterns utilized for security applications and programmable key patterns which may be changed to accommodate different locks of mechanical, optical or electronic type.
[0006] The invention is useful with any sort of storage medium related to pluralities of sets of information, data or patterns which are desired to be used by a user. For example the invention may be used with mechanical, magnetic, electrical, optical, film, holographic or other recording or storage of information or patterns as will become apparent to one skilled in the art from the teachings given herein. The invention thus provides simulation of multiple sets of data, information or patterns stored in a spatial pattern by providing a memory or storage device for storing data from which the spatial patterns may be reconstructed. Also included is a programmable spatial device capable of reconstructing the spatial patterns under control of a circuit responsive to an external inputs which cause the programmable spatial device to be programmed to reconstruct the spatial patterns from the data stored in the memory. The spatial patterns may take on multiple dimensions and may be time varying and the memory may be electronic, mechanical, optical or other type as will be apparent to one of ordinary skill in the art from the teachings herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a drawing demonstrating a prior art credit card with a magnetic stripe.
[0008] FIG. 2 is a drawing demonstrating the preferred embodiment of the present invention.
[0009] FIG. 3 is a drawing explaining the operation of the preferred embodiment of the invention.
[0010] FIG. 4 is a drawing showing details of the programmable magnetic strip of the preferred embodiment of the invention.
[0011] FIG. 5 is a drawing showing a cross sectional view corresponding to FIG. 4 .
[0012] FIG. 6 is a drawing showing the invention as used with a key.
[0013] FIG. 7 is a drawing showing another mechanical configuration of the preferred embodiment of FIG. 2 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] FIG. 1 is a drawing demonstrating a prior art credit card in diagram form, having a strip of magnetic material 2 which is embedded in a plastic substrate 1 which magnetic strip carries a pattern of magnetization which is a magnetic representation of information or patterns relating to the credit card. FIG. 1 shown in graphical form the top and front edge view of the magnetic strip with a representation of the magnetic flux recorded therein.
[0015] FIG. 2 shows a diagram of the preferred embodiment of the present invention, dubbed a multi-card by the inventor, having a plastic substrate 3 , on which is suitably mounted a programmable magnetic strip 4 , an LCD display 5 , a solar cell power source 6 , including an electricity storage cell (not shown), an infrared emitter 7 , and infrared sensor 8 , and a key pad 9 consisting of 14 operator actuated switches. It will be appreciated that these switches may be capacitive type touch sensitive sensors or other types. It will be understood that the programmable magnetic strip 4 may also be of a type which may sense magnetic information or patterns, and thus may be used as an input or output device.
[0016] Programmable magnetic strip 4 is preferred to be operated to approximate, duplicate or replicate a magnetic pattern matching the particular need of the operator in response to the operator's commands or inputs to the card as will be described in more detail below.
[0017] In operation, the multi-card has stored in it several sets of data corresponding to account related information or patterns for different credit cards, identification cards and the like. Power for the operation of the device is provided by a solar cell, which power is stored in a storage battery. The battery is preferred to be replaceable with a charged battery for those applications where the solar cell does not receive enough light to operate the multi-card, however it is preferred that devices which make use of the multi-card provide sufficient illumination to the solar cell to power the device.
[0018] To operate the multi-card, the operator simply presses a given key, which may be a touch sensitive pad, which causes multi-card to activate and the display 5 to display which account is associated with that key. If the operator forgets which key is associated with a wanted account, he may simply operate all keys in sequence until the correct account is selected. It will be understood that it is also possible to provide only one key, with a different account called up for each press.
[0019] When each account is called, the magnetic data for that account is loaded into the magnetic strip 4 , causing the magnetic strip to simulate the magnetic strip on the prior art type card by emulating, approximating, replicating or duplicating the magnetic pattern, depending on the accuracy required by the device reading the pattern. The control of the accuracy provided may be provided by the operator, or may be automatic in response to feedback (or lack thereof) by the device using the card. In this fashion, the multi-card may then be placed into a card reader or other device which reads the magnetic pattern from the magnetic strip to allow the holder access to the account, services or features associated with the stored data or pattern.
[0020] It will be recognized by one of ordinary skill in the art from the teachings herein that the invention allows access to numerous accounts, services, features, etc. with just one card thereby eliminating the need to carry, store or retain numerous cards. Other features may be combined with the invention as well, or as the case may be the invention may be combined with other functions, examples including personal reminder and memory capability, calculator and clock or even telephone and television functions.
[0021] Other sequences of operation of the invention may be utilized as well. For example, the key pad may be used to enter a convenient select designator, for example a BC representing bank card or a PBC indicating personal bank card, or any other convenient select designator. The select designator will then cause the account identifier to be displayed on 5 and the proper pattern loaded into 4 . In addition, the loading of pattern into 4 may be caused to occur only when another command is generated by the operator, or only upon or after insertion of the card in a device which uses it. These operations are considered to be novel features of the invention.
[0022] It will be understood by one of ordinary skill in the art that elements 3 and 5 - 9 are well known and commonly found and utilized in the industry and may be controlled by a microprocessor with their application and use in the preferred embodiment of the invention being within the capability of one of ordinary skill in the art.
[0023] FIG. 7 shows an top and side views of an alternate mechanical embodiment similar to FIG. 2 . The mechanical embodiment of FIG. 7 has the advantage of allowing a larger space for the electronics while maintaining a thin cross section in the “card” area, thus allowing easier fabrication.
[0024] FIG. 3 shows a diagram of the multi-card and a supporting console which may be used to store information or patterns in the multi-card or recover information or patterns from the multi-card, or another card. A control circuit 11 , which is preferred to be a microprocessor such as an Intel 80C31 or which may have internal ROM, ram and nonvolatile ram as is known in the industry, is utilized to control and operate the various elements of the multi-card.
[0025] As an example the Intel 80C31 series microcontroller is well suited to the control task. When the 80C31 is coupled with a nonvolatile ram such as the Xicor X2444 available from Xicor, Inc. 1511 Buckeye Drive, Milpitas, Calif., a keypad such as can be easily constructed with the ITT Schadow KSA1M211 switch available from ITT Schadow Inc. 8081 Wallace Rd., Eden Prairie, Minn., and an LCD display such as the Optrex DMC20261NY-LY-B, available from 44160 Plymouth Oaks Blvd., Plymouth, Mich., the invention components may be readily constructed. A 16 keypad matrix in 4.times.4 form (not all 16 need be used) is preferably configured on the 8 P1 port connections, the LCD is preferably configured on the P0 data port under write control as addressed by the P2 data port and controlled by the /WR control. The input/output interface 14 is preferably provided via the TXD/RXD serial ports (alternate functions provided on the P3 port), and the nonvolatile ram is preferably configured directly to the /INT0, ANT0I and T0O pins of the P3 port. The program instructions to run the processor are preferably stored in an EPROM having data pins coupled to the P0 port and addressed by the P2 port under /RD read control as is commonly known in the industry. Intel provides a wealth of information on configuring, programming and operating this and many other processors, which information is available from Intel Corporation, 3065 Bowers Ave., Santa Clara, Calif.
[0026] The programmable magnetic strip 10 is preferred to contain multiple inductive coils to generate magnetic fields in response to current flowing therein, as will be described in more detail below. The connection of the processor of 11 , be it an 80C31 or other type may be made directly via matrixing of the two connections of the individual coils in 10 , for example as is commonly done to write (and read from) core type magnetic memory in the computer industry. Alternately, a large serial shift register array may be loaded with serial binary data under control of 11 with the array's output being enabled to a low impedance state from a high impedance state after loading. The binary data may thus cause the many parallel outputs, each of which is coupled to a coil, to source electrons into the coil, or sink electrons from the coil, providing that the other end of each coil is connected to a voltage source which is midway between the output's high and low logic level states. To achieve control over the current flow through the coils, multiple serial shift registers may be utilized, with several outputs being coupled to each coil through resistors or other current controlling circuits, the pattern of data in the several outputs controlling the current flow.
[0027] Several variations of the suggested elements of the preferred embodiment may be utilized as will be convenient to implement particular embodiments of the invention which may be configured to specific needs and applications, as will be apparent to one of ordinary skill in the art from the teachings herein.
[0028] The substrate 3 may be of any material on or to which the other elements may be suitably secured or attached, examples including the preferred PVC plastic, ceramic, metal and others. Display 5 which is used to provide messages to the user of the device may be of any electro optical type such as LCD, LED, CRT, incandescent, fluorescent, flip dot, etc. or may be of electro mechanical type such as beeper, buzzer, vibrator, etc., or may be eliminated in applications where it is not desired to convey messages to the user, or where messages are conveyed via other means. Such other means for example include via the device which reads the magnetic strip 4 .
[0029] Power source 6 may be any well known power source, such as solar cell, battery, electric generator operating to convert motion to electricity, fuel cell, electromagnetic or electric field receiver, piezoelectric generator, etc. or any combination thereof.
[0030] Emitter 7 may be the preferred infrared LED, antenna, coil, transducer, or any other device capable of conveying information or patterns from the invention to outside devices, and receiver 8 is preferred to be a photo transistor but may also be any such apparatus or device capable of receiving information or patterns from outside devices to be used by the invention. Either or both of the emitter and receiver may be eliminated if the capability provided is not desired, or is otherwise provided for. For example, the sensing capability of 10 or the input capability of 13 may be utilized to provide the receiver 8 function and the display 12 may be utilized to provide the emitter function.
[0031] Touch sensitive key pad 9 may be capacitive, heat sensing, optical or mechanical switches, etc. or any device capable of receiving and coupling operator input to the invention. The operator interface 13 and its key pad 9 may also be eliminated if no operator interface is desired.
[0032] The control circuit operates with the programmable magnetic strip 10 , examples include those corresponding to 4 of FIG. 2 , to create a predetermined magnetic pattern which may be read by compatible reading devices, and may also operate in conjunction with 10 to sense magnetic patterns. Control circuit 11 also drives the LCD display 12 , examples including associated with 5 of FIG. 2 , to display messages to the operator and as signified by the dotted arrow on the control circuit 11 may also operate interactively with 12 . Control circuit 14 operates interactively with the input/output interface 14 , examples including those associated with 7 and 8 of FIG. 2 , to communicate with the console. Control circuit 11 also operates interactively with operator interface 13 , examples including those corresponding to 9 of FIG. 2 , to allow operator input to the control circuit. Also shown in FIG. 3 is a power source 15 , examples including those associated with 6 of FIG. 2 , and which provides power for the operation of the multi-card. In the preferred embodiment, 15 includes a replaceable nickel cadmium battery and solar cell allowing the battery to be replaced and/or recharged. It is of course possible to use either replaceable or rechargeable power sources.
[0033] FIG. 3 includes a console comprised of programming circuitry 16 and card reader 17 . In operation, the card reader may be operated to read information or patterns from a particular data storage medium, examples including the magnetic strip on a credit card. The information or patterns may be read as the actual data represented in any of its various forms, or may be read simply as the representation. With respect to reading a magnetic stripe, the reader may simply read the magnetic pattern without concern as to the data represented thereby, or may decode the magnetic pattern into the encoded (that is represented) data, or may decode the data to the unencoded (that is unprotected by security scrambling and the like) data as is convenient. In the preferred embodiment, the magnetic pattern is simply sensed at a high resolution by moving the magnetic strip over a magnetic sensor and generating a binary representation of the polarity of the magnetic field in response thereto. The resulting binary pattern corresponds to the magnetic polarity field, in the preferred embodiment at 0.001 inch increments, giving a linear “snapshot” of the magnetic pattern.
[0034] The binary representation is then coupled to the programming circuitry 16 (via 14 ) where an account identifier is associated therewith to later be displayed on the display 12 when the wanted corresponding magnetic pattern is recalled from the memory in the control circuit 11 . While called an account identifier, there is no need that the pattern correspond in any way to an account, and may well correspond to anything. The account identifier may be thought up by the operator, may be chosen by the operator from a list or other source, or may be assigned without operator intervention, for example preprogrammed in the card which is read or in the control circuit 11 . The input of the account identifier may be via 13 or 16 as is desired. It is however preferred that the operator may have some choice in the matter in order that an account identifier which is either convenient to or associated by the operator is used, and thus it is preferred that 16 contain a keyboard with which the operator may type in his desired identifier, and the desired key, key sequence or location associated therewith.
[0035] It is also preferred to associate a select designator with the binary representation, in order to allow the operator to utilize the select designator to call up a particular magnetic pattern. The select designator may be thought up by the operator, may be chosen by the operator from a list or other source, or may be assigned without operator intervention, for example preprogrammed in the card which is read or preprogrammed in the control circuit 11 at the time of manufacture or other time.
[0036] In operation, it is preferred that there be more than one method for the operator to call up a wanted pattern. One preferred way is for the operator to enter the select designator. This causes the account identifier to be displayed in 12 . Alternatively, the operator may scroll through all the possible sets of data, viewing each account identifier as it appears until the desired one is called up, or may key in a more detailed pattern, to call up the desired account.
[0037] The magnetic pattern (or data represented thereby in some form) is then caused to be stored in the memory of 11 in a form which allows it to be associated with the identifier, and preferably also with some known input terminal or sequence of terminals of 9 . In the preferred embodiment, the operator chooses an available key of 9 (for example the upper right) or other select designator, provides an account identifier, (for example BANK CARD) and the operator choices and data are stored in 11 in a fashion which associates them all. It is preferred that the data be stored in nonvolatile memory in order that it will be retained in the event that the power storage device of 15 is fully discharged or the control circuit is turned off, for example to save power.
[0038] It is preferred that by utilizing the foregoing programming procedure, the operator stores the magnetic pattern, account identifier and desired associated select designator in 11 . Upon subsequent entry of the associated select designator, the control circuit 11 recalls the associated data corresponding to the magnetic pattern and the account identifier from memory. The account identifier is loaded in the display 12 to remind the operator what the data is associated with, and the magnetic pattern is caused to be replicated in 10 from the stored data. The replicated magnetic pattern in 10 may then be utilized to operate a card reading device to provide the operator access to the account, services, features or other conveniences associated therewith, and hence associated with the card which was read by 17 .
[0039] It is of course desired to provide the capability of storing several such sets of associated data, identifier and key in the memory of 11 , and it is further desirable to provide for the association of multiple select identifiers with a given set of data. By way of example, in this fashion, a set of data for generating a magnetic pattern for a company issued bank card may be called up by use of any of the select identifiers cc, or COCARD or COMPANY CARD, etc. and another set of data for a personal bank card may be called up by use of any of the select identifiers PC, PBC, etc.
[0040] FIG. 4 shows a diagram of the details of the magnetic strip 10 and control circuit 11 , including individual electromagnet coils, one of which is shown as 21 and having electric circuit connections 22 and 23 , and magnetic flux conducting material 20 . It will be recognized that by passing an electric current through a given coil that a magnetic flux will be created across the associated gap in the magnetic flux conducting material 20 above the coil, such as is represented by 24 . Furthermore, the flux for each coil will be largely contained in the gap corresponding to that coil by the magnetic flux conducting material. The polarity of the flux may of course be changed by changing the direction of current flow through the coil, and the intensity of the magnetic flux may be varied by varying the electric current through the coil. In this fashion, the original magnetic pattern which was read by reader 17 may be approximated, duplicated or replicated as required. While it may be desirable to cause the control circuit 11 to have the ability to vary the accuracy with which it stores the magnetic data or programs the magnetic strip, it will be recognized that this is not a requirement, and 11 may simply operate to a single given accuracy. It may also be noted that the material used for 20 may be of a type having a large magnetic memory or hysteresis so that once a magnetic pattern is generated in the material, the electric current through the coils may be turned off or reduced and the magnetic field will remain. Techniques which are used to write and read magnetic core type memory, as well as the materials used therefore, will be applicable to the generation of magnetic patterns for 10 , and the technology used in the core industry may be easily adapted to be used in fabricating 10 . It will also be recognized that other methods of creating magnetic patterns may be utilized as well, such as various chemical, thermal and optical methods which may be utilized to create magnetic flux patterns, or to alter existing flux patterns.
[0041] FIG. 5 shows a sectional diagram A-A of elements 20 - 23 of FIG. 4 and the preferred method of construction thereof. This method of construction is readily implemented with either photographic lithography and lamination techniques or with chemical vapor etching and deposition as are commonly utilized to fabricate miniature electronic circuits. Other construction methods may be utilized as well.
[0042] Element 18 is a substrate material, examples including plastic or ceramic, on which the magnetic coils 21 may be built. a conductive layer 19 is formed on the substrate in a predetermined pattern to make up the bottom half of the coils 21 . This layer may be created by depositing or printing a continuous metallic film and then etching away all but the desired conductive paths, or by photographically printing the conductive paths. Next, the magnetic material 20 is formed on top of the bottom conductive paths. Preferable the magnetic material is an electrically non-conductive or low conductive material, but if it is conductive, an insulating layer may first be deposited to prevent it from shorting out the top and bottom conductive paths. After the magnetic material is formed the top electrically conductive layer is formed thereover using the same process as for the bottom, thus completing the coils 21 . Finally, conductive wires or circuits 22 and 23 are bonded to the coils for connection to 11 , and the entire magnetic strip is provided with an environmentally insulating covering if desired to shield from moisture, corrosion, etc. By utilization of this method, it will be seen that very low manufacturing cost and small size may be obtained. It will also be understood that the linear array of coils is given by way of example with respect to the preferred embodiment and may be arranged in other than a linear fashion, for example in circular or three dimensional patterns. It will also be understood that the magnetic coils may be replaced with LEDs to create emitted light patterns, or by LCD elements to create reflected or transmitted light patterns, or by any other type of energy radiator, absorber or deflector in order that the invention may be practiced with virtually any sort of emitted, absorbed or deflected pattern.
[0043] It will be recognized that while the coils may be utilized to generate a magnetic pattern, they may also be utilized to sense a magnetic pattern. While some motion is required to generate an electric current in the coils, this motion may be supplied by the user. In addition, magneto restrictive materials may also be adopted to allow sensing of magnetic patterns without motion. One of ordinary skill in the art will be able to construct such a device and practice the invention from the teachings of the preferred embodiment given herein without undue experimentation or further invention. It will also be recognized that it will be possible to have magnetic strip 10 sense the magnetic pattern on another magnetic strip directly, removing the need for card reader 17 . It would also be possible to incorporate the programming circuitry 16 in the control circuit 11 , thus completely eliminating the need for the console of FIG. 3 . Once the console is eliminated, the input/output interface 14 may also be eliminated.
[0044] One skilled in the art will also recognize that an inexpensive version of the invention may be constructed of simply a programmable magnetic strip 10 which can both read and simulate a magnetic pattern, a control circuit 11 , an elementary operator interface 13 and a power source 15 .
[0045] Alternatively, instead of a magnetic strip 10 capable of reading, several preprogrammed magnetic patterns may be programmed in control circuit 11 upon manufacture, either by storage of the magnetic patterns, storage of data which may create the magnetic patterns or storage of an algorithm or method by which the magnetic pattern may be created in 10 under control of 11 . In such a system, only elements 11 and 10 are absolutely required since it would be possible for 11 receive commands from the reading device via 10 , or to simply try all stored patterns in 10 upon excitation or connection of the power source 15 .
[0046] While the preferred embodiment of the invention has been given by way of example with respect to credit cards having magnetic strips, it will be recognized that the invention may very well be adapted for use with other methods of storage and storage medium. Examples include, simulating two or more dimension patterns. Optical devices which record data on film in two or more dimensions may be replaced by liquid crystal or other optical displays which simulate the patterns recorded on the film. Holographic recordings may also be simulated by LCD or other optical displays. Mechanical devices may be replaced by electromechanical devices in which mechanical dimensions are adjusted via solenoids, motors, piezoelectric cells or the like. Keys are an excellent example of a device which may be replaced by a battery of such adjustable devices.
[0047] In FIG. 6 for example, the device of FIG. 3 may be utilized in conjunction with micro machines in order to create an adjustable key in which the operator selects an identifier corresponding to the particular lock which he wishes to unlock. The device uses electromagnetically driven micromotors and worm screws to adjust the serrated edge on the key to fit the lock. A sectional view of the device is shown in which a standard key blank 25 is machined to couple to a bank of micro motors or solenoids 26 , each of which is connected via a worm screw to a flexible shaft or wire which extends to the serrated edge of the key.
[0048] By way of example, micromotor 27 is coupled to flexible shaft 28 which passes through a hollow portion of the key blank 25 to the serrated edge where it protrudes through the blank at 29 . Individual channels may be micromachined for the flexible shafts, or the shafts may simply be sized to fill the slot in the key blank, or bundled together to prevent lateral displacement which would affect the protrusion distance from the edge of the key blank at 29 . The micromotor 27 , via the screw, adjusts the position of the end of 28 to thereby control the length of protrusion of the other end at 29 , thus adjusting the depth of the serration at that point. All of the micrornotors in the bank 26 are coupled to the control circuit 11 of FIG. 3 by a suitable coupling. In this fashion, the key may be adjusted to fit different locks as desired by the operator. In this example, card reader 17 may be replaced with a key reader in order that the serration pattern of precut keys may be read into 11 and stored, along with account identifiers, select designators, etc. as previously described.
[0049] In view of continuing development of micro machines on silicon wafers by use of semiconductor fabrication techniques, it is envisioned that it will be possible to manufacture both electro mechanical components such as solenoids and the corresponding electrical control circuitry all on the same semiconductor substrate. In this fashion, it would be possible to manufacture the invention of FIG. 6 , including the necessary control circuitry of FIG. 3 entirely with existing semiconductor fabrication technology.
[0050] It would also be convenient to replace the electronic storage of different patterns with a mechanical or other storage of patterns, for example with respect to the key of FIG. 6 on a rotating cam shaft, shown as 27 of the inset, which would be rotated to adjust the height of spring loaded pins on the key, the springs holding the pins against the cams. While the configuration of the inset would require a fairly wide key, the camshaft could also be located entirely within the handle of the key and be coupled to the spring loaded pins via flexible shafts or wires 28 as with the micromotor actuator 26 . The account identifiers or select identifiers can be engraved directly on the end of the shaft. It will be understood that the flexible shafts may be arranged in other than a linear fashion, for example in circular or three dimensional patterns.
[0051] The invention described herein by way of explanation of the preferred embodiment may be practiced with numerous changes in the arrangement, structure and combination of the individual elements, as well as with substitution of equivalent functions and circuits for the elements in order to optimize the invention for a particular application, all without departing from the scope and spirit of the invention as hereinafter claimed. | The apparatus and method described herein provides for creating multiple spatial patterns, such as magnetic patterns on credit cards. The invention includes storage of information from which patterns may be created, a pattern creation device for creating the spatial patterns, and control whereby the information which is stored is selectively utilized to cause the pattern creation. This allows multiple desired patterns to be simulated, allowing convenient replacement of a number of separate pattern carrying devices. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a process for synthesizing dispersion of ZnO nanoparticles in an oil medium. Particularly, the invention relates to a process for in-situ synthesis of ZnO nanoparticles in an oil medium.
BACKGROUND OF THE INVENTION
[0002] The anti-wear (AW) and extreme pressure (EP) additives are mainly used for reducing friction and wear under boundary lubrication conditions. These additives are vital constituents of most lubricant formulations, under conditions of medium to high or extreme pressure, react with mating metal surfaces forming protective tribo-chemical layers. Thus the equipments are protected from wear and enabled to operate successfully under heavy loads.
[0003] Generally, any chemical constituent, pure or impure, intended or not, that is formed or deposited during lubrication on the metal surface, and able to separate and prevent the opposing surfaces from direct contact could theoretically be construed as AW/EP agent. Therefore, the classic AW/EP additives are oil-soluble chemicals or components which react with the metal surface forming a film that withstands both compression and, to a degree, shear. Since reaction with the metal is of the essence, only elements that can form iron compounds are truly eligible for this task. That makes compounds of sulfur, phosphorus, chlorine (or other halogens) preferential choices.
[0004] Traditionally, wear protection and friction modification by engine oil is provided by zinc dithiophosphate (ZDDP), molybdenum dithiophosphate (MoDDP) or other phosphorus compounds. These additives provide effective wear protection and friction control on engine parts through formation of a glassy polyphosphates anti-wear film. However, these additives may have one or more disadvantages such as;
1. copper and/or lead corrosion, 2. color darkening of the finished lubricant, 3. increased levels of sulfur and phosphorus in the finished lubricant.
[0008] Among these disadvantages the level of phosphorus and sulfur in the engine oil is the most serious concern. This is because the deposition of phosphorus and sulfur species on automotive three way catalytic converters from lubricants has been known for some time to have a detrimental effect on poisoning the catalysts. Future generations of passenger car motor oils and heavy duty diesel engine oils require lower levels of phosphorus and sulfur in the finished oil in order to protect the pollution control devices. Hence the limits of phosphorus and sulfur levels in engine oil are reduced and supplemental forms of AW additives will be required to replace ZDDP. For example, current GF-4 motor oil specifications require a finished oil to contain less than 0.08 and 0.7 wt % phosphorus and sulfur, respectively and PC-10 motor oil specifications, the next generation heavy duty diesel engine oil, requires to contain less than 0.12 and 0.4 wt % phosphorus and sulfur, respectively. Certain molybdenum and organo zinc additives known in the industry contain phosphorus and sulfur at levels which reduce the effectiveness of pollution control devices.
[0009] Much work has gone in to reducing the level of ZDDP in lubricants by increasing the use of known friction modifiers, other phosphorus free components or balancing the properties of many compounds but this is difficult because ZDDP is not a mono-functional additive that provides only AW chemistry but has multifunctional properties providing anti-scuffing and anti-oxidation, all in one additive component.
[0010] In addition, it has complex interactions with other additives. Another approach is to modify the ZDDP molecule to have the same activity at lower concentrations by changing the alkyl group but a stable anti-wear ZDDP film cannot be formed by the modified ZDDP at low concentrations. Nevertheless, the ability to formulate with ashless dispersants would also benefit from the replacement of ZDDP chemistry. Ashless dispersants deteriorate the anti-wear performance of ZDDP because the amount of ZDDP adsorbed onto the metal surfaces is decreased by formation of complexes with ashless dispersants in oil. Therefore, lubricant additives and/or composition that delivers spectacular anti-friction and wear properties and as well as compatible with pollution control devices used for automotive and diesel engines are highly demanded.
[0011] Such lubricant additives and/or compositions compatible with pollution control devices should also not adversely affect oil solubility, corrosion and darkening the color of the finished lubricant.
[0012] With rapid development of nano-science and technology, nanoparticles have received considerable attention in recent years because of their special physical and chemical properties. Especially in the field of tribology, many kinds of inorganic nanoparticles have been successfully used in lubricating oils and greases to solve wear and friction problems. The dispersion of inorganic nanoparticles in lubricating oil is still a principal problem for application of nanomaterial additives. In order to obtain better dispersion, a surface modification technique is usually adopted to structure an organic layer on the surface of nanoparticles. As compared to the conventional additives either containing heavy metals like Zn, Mo and Pb etc., or too much sulfur and phosphorus, greener nanomaterial additives with environmentally benign characteristics are strongly required.
SUMMARY OF THE INVENTION
[0013] Accordingly, the present invention provides a process for preparing a dispersion of ZnO in an oil additive composition, wherein the process comprises the steps of:
[0014] a) dissolving a zinc salt in an alcoholic solvent and heating to 60-120° C. for 6-48 h hours to obtain a suspension;
[0015] b) centrifuging the suspension as obtained in step (a) and washing with deionized water to obtain a precipitate of layered base zinc (LBZ);
[0016] c) dispersing the layered base zinc precipitate as obtained step (b) in an alcohol and adding to base oil containing a dispersant;
[0017] d) refluxing the mixture to obtain a colloidal suspension;
[0018] e) evacuating the colloidal suspension at room temperature and heating at 60-90° C., followed by heating to 45 to 120 minutes to obtain a dispersion of ZnO in the oil medium.
[0019] In an embodiment of the present invention, the hydrous or anhydrous form of zinc salt is selected from zinc acetate, zinc nitrate; zinc chloride; zinc sulfate; zinc hydroxide (hydrotalcite); zinc hydroxy carbonate or hydrozincite; zincite and wurtzite.
[0020] In another embodiment of the present invention, the alcoholic solvent is selected from C 1 to C 3 alcohols.
[0021] In yet another embodiment of the present invention, the ratio of zinc salt and the alcoholic solvent ranges from 0.05 to 15: 1 to 740.
[0022] In still another embodiment of the present invention, heating in step (a) is performed to 90° C. in an autoclave or refluxing in a glass reactor.
[0023] In further another embodiment of the present invention, the washing in step (b) is performed twice with deionized water.
[0024] In another embodiment of the present invention, the alcohol in step (c) is selected from C 1 -C 3 alcohols.
[0025] In still another embodiment of the present invention, the amount of the dispersant in the base oil ranges from 40-78%.
[0026] In yet another embodiment of the present invention, the layered basic zinc salt is selected from layered basic zinc acetate, layered basic zinc nitrate; layered basic zinc chloride; layered basic zinc sulfate; layered zinc hydroxide (hydrotalcite); zinc hydroxy carbonate or hydrozincite; zincite and wurtzite.
[0027] In one another embodiment of the present invention, the dispersant is selected from PM dispersants, Phosphorodithioic acid; Ethyl hexanoic acid or fatty acids like stearic, oleic acids; sorbitane mono oleate (SPAN 80); sorbitane mono laurate (SPAN 20); sorbitane mono stearate (SPAN 60); Tween 20 (polyoxyethylenesorbitane mono laurate); Tween 60 (polyoxyethylenesorbitane mono stearate); Tween 80 (polyoxyethylenesorbitane mono oleate); diethanolamide fatty acid and fatty acid mono glyceride.
[0028] In still another embodiment of the present invention, the base oil is a mineral oil selected from the group consisting of group I, group II, group III, group IV, group V and synthetic oils.
[0029] In yet another embodiment of the present invention, the composition comprises a base oil, a dispersant and a dispersion of ZnO as obtained by the process as claimed in claim 1 .
[0030] In further another embodiment of the present invention, the amount of the base oil in the composition ranges from 20 to 98.5.
[0031] In another embodiment of the present invention, the amount of the dispersant in the composition ranges from 1.55 to 78.
[0032] In one another embodiment of the present invention, the amount of the ZnO ranges from 0.1 to 5.
[0033] In still another embodiment of the present invention, the layered basic zinc salt is selected from layered basic zinc acetate, layered basic zinc nitrate; layered basic zinc chloride; layered basic zinc sulfate; layered zinc hydroxide (hydrotalcite); zinc hydroxy carbonate or hydrozincite; zincite and wurtzite.
[0034] In one another embodiment of the present invention, the dispersant is selected from PIB dispersants, Phosphorodithioic acid; Ethyl hexanoic acid or fatty acids like stearic, oleic acids;
[0035] sorbitane mono oleate (SPAN 80); sorbitane mono laurate (SPAN 20); sorbitane mono stearate (SPAN 60); Tween 20 (polyoxyethylenesorbitane mono laurate); Tween 60 (polyoxyethylenesorbitane mono stearate); Tween 80 (polyoxyethylenesorbitane mono oleate); diethanolamide fatty acid and fatty acid mono glyceride.
[0036] In another embodiment of the present invention, the base oil is a mineral oil selected from the group consisting of group I, group II, group III, group IV, group V and synthetic oils.
BRIEF DESCRIPTION OF DRAWINGS
[0037] FIG. 1 : FIG. 1 shows particle size distribution of ZnO nanoparticles in the range 100-400 nm.
[0038] FIG. 2 : FIG. 2 is high resolution image shows preferentially oriented lattice fringes of ZnO (Zincite phase; d=2.6033 A; 20=34.422) whereas figure inset shows XRD of ZnO nanoparticles obtained by heating LBZA at 150° C. for 6 h.
DESCRIPTION OF THE INVENTION
[0039] The present invention discloses aprocess for in situ synthesis of ZnO nanoparticles in a medium. Particularly, the present invention also discloses a process for in situ process for synthesizing ZnO nanoparticles in base oil.
[0040] It is well known that in the art that the decomposition of layered basic zinc (LBZ) yields flakes of porous nano ZnO. The present invention provides a two-part procedure comprising of steps discussed herein for synthesizing ZnO nanoparticles within oil medium.
[0041] For the first part of the two-part procedure, LBZ was prepared as per existing open literature procedures. In an embodiment of the present invention, LBZ was prepared by dissolving Zinc salt in an alcoholic solvent and heating to 90° C. in an autoclave or refluxing in a glass reactor for 24 hours to obtain a white suspension. The product was centrifuged and washed twice with deionized water to precipitate LBZ.
[0042] For the second part, the present invention provides a method of synthesizing ZnO Nanoparticles by decomposing LBZ in an oil medium. LBZ as obtained in the first part was dispersed in a C1-C3 alcohol and added to base oil containing 40-60% of PM dispersant. The mixture is refluxed to give a colloidal suspension. The suspension was evacuated at room temperature in a rotavapor setup and heated to 90° C. to remove the alcohol solvent followed by heating to 140° C. for 45 to 90 minutes for LBZ decomposition to give a clear dispersion of ZnO in the oil medium along with residual anions. The evolved during decomposition were removed through vacuum stripping. Acetic acid is obtained as by-product of vacuum stripping.
[0043] In accordance with the present invention, the alcoholic solvent is selected from C1-C3 alcohols. In accordance with the present invention, the dispersant is selected from PIB dispersants, Phosphorodithioic acid; Ethyl hexanoic acid or fatty acids like stearic, oleic acids; sorbitane mono oleate (SPAN 80); sorbitane mono laurate (SPAN 20); sorbitane mono stearate (SPAN 60); Tween 20 (polyoxyethylenesorbitane mono laurate); Tween 60 (polyoxyethylenesorbitane mono stearate); Tween 80 (polyoxyethylenesorbitane mono oleate); diethanolamide fatty acid; fatty acid mono glyceride.
[0044] In accordance with the present invention, layered basic zinc salt is selected from layered basic zinc acetate, layered basic zinc nitrate; layered basic zinc chloride; layered basic zinc sulfate; layered zinc hydroxide (hydrotalcite); zinc hydroxy carbonate or hydrozincite; zincite and wurtzite. In accordance with the present invention base oil is group II base oil.
[0045] Having described the basic aspects of the present invention, the following non-limiting examples illustrate specific embodiment thereof.
EXAMPLE 1
[0046] About 100 ml of liquor solution of zinc acetate dihydrate (Zn(CH 3 COO) 2 .2H 2 O) in the concentration 0.15 moles per cubic decimeter was charged in a round bottom flask fitted with a reflux condenser and heated for 24 h to give white precipitate. The precipitate was filtered and washed twice with distilled water to give fine white product layered basic zinc acetate (LBZA) of formula Zn 5 (OH) 8 (CH 3 COO) 2 .2H 2 O. The product was re-suspended in isopropyl alcohol (25 ml) for further use.
EXAMPLE 2
[0047] To a 500 ml two neck round bottom flask containing 60 g PIBSI dispersant and 16 g group II base oil added the alcohol suspension prepared from the example 1 and heated to reflux condition. The colloidal product was transferred to rotavapor flask and solvent was stripped under vacuum at 90° C. and then heated further to 140° C. under vacuum to remove decomposing acetates to give clear stable product containing 1.45 Wt % of Zn (metal content). The product could readily be dispersed in any mineral oil of lubricating viscosity.
[0048] TEM images of ZnO nanoparticles present in the oil mediumare shown in FIG. 1 and FIG. 2 ; The product concentrate is free of any significant acidic components (Total Acid Number (TAN)=0.657 mgKOH/g) when subjected to TAN determination as per ASTM D664.
EXAMPLE 3
[0049] To a 750 ml high pressure reactor (Parr Instruments) added 300 ml alcohol solution containing zinc acetate dehydrate (Zn(CH 3 COO) 2 .2H 2 O) in the concentration 0.05 moles per cubic decimeter and heated at 95° C. for 24 h to give highly viscous colloidal white precipitate. The product was washed thoroughly by centrifuge with distilled water for three times before being mixed with 50 ml isopropyl alcohol to give a colloidal suspension for further use.
EXAMPLE 4
[0050] The suspension obtained from the example 1 was mixed with 10 g of 2-ethyl hexanoic acid (EHA) and mixture was heated at 150° C. under vacuum to remove the solvent and decomposing acetates. The final product was clear and stable which could be dispersible in nonpolar medium like mineral oil. Similarly Span 80 (sorbitane mono oleate) was also used in the place of EHA in another reaction run to give Span based metal dispersion.
EXAMPLE 5
[0051] The product as per Example 2 was diluted with Gr II base oil to get ppm (parts per million) level of Zn concentration in final dispersion blends which were evaluated for antiwear performance in four ball tester (Falex wear test machine) at 348K; 15 kg weight load (ASTM D4172). The tests were repeated two times (results with best precision were considered) and Wear Scar Diameter (WSD) results are summarized for neat base oil and blends in the below Table. WSD should be less for any good antiwear candidate.
[0000]
TABLE 1
Metal Concentration (ppm)
Dispersant (Wt %)
Zn (ZnO)
WSD
0
0
0.65
1.55
0
0.70
1.55
430 (534)
0.35
1.55
465 (578)
0.40
1.55
136$ (169)
0.50
1.55
182* (226)
0.45
1.55
500# (634)
0.35
1.55
250 (312)
0.45
[0052] $Span-80 and *EHA stabilized samples from example 7; #ZDDP blend. TAN value of above blends was not detectable as per ASTM D664 indicates no significant acid components present in these blends.
EXAMPLE 6
[0053] About 500 ml of liquor solution of zinc acetate dihydrate (Zn(CH 3 COO) 2 .2H 2 O) in the concentration 0.15 moles per cubic decimeter was charged in a round bottom flask fitted with a reflux condenser and heated for 24 h to give white precipitate. The precipitate was filtered and washed twice with distilled water to give fine white product layered basic zinc acetate (LBZA) of formula Zn 5 (OH) 8 (CH 3 COOO) 2 .2H 2 O. The product was resuspended in isopropyl alcohol (100 ml) and slowly (over 20 minutes) mixed at 60° C. with 50 g of Gr II base oil containing 100 g PIBSI based dispersant (M.W 1400) in a two neck round bottom flask. The reaction mixture were heated to reflux condition and transferred to a rotavapor flask to remove the solvent under vacuum at 90° C. The obtained mixture was heated further to 140° C. under vacuum for another 45 minutes to give clear product containing Zn metal in the concentration of 1.85 Wt %.
[0054] The product was top treated with formulated marine oil to get ppm (parts per million) level of Zn concentration in final dispersion blends which were evaluated for antiwear performance in four ball tester (Falex wear test machine) at 348K; 40 kg load and weld load measurement. The tests were repeated two times (results with best precision were considered) and WSD results are summarized for formulated oil and top treated blends in the below Table.
[0000]
TABLE 2
Metal Concentration
(ppm)
WSD
Weld load
Sample
Zn (ZnO)
(mm)
(Kg)
1040
0
0.50
180
1040
500 (634)
0.50
180
EXAMPLE 7
[0055] Preparation of ZnO Dispersion by Ex Situ and Mixing approach:
(a) 12 g of Zinc acetate-di-hydrate, was mixed with 300 mL of methanol and the mixture was refluxed for 24 h to give white precipitate, which was washed twice with distilled water. The obtained precipitate was dried at 70° C. for 6 h and then heated to 150° C. for 6 h. The final half white mass was mixed with requisite amount of PM dispersant and group II base oil in a ratio 3.3 to 1, dispersant and Zn metal in a ratio 30 to 1 so as to obtain final Zn metal concentration 2.5 Wt % in the total concentrate. This method of making dispersion is Ex situ approach. (b) 0.31 g of commercial ZnO was mixed with required amount of PM based dispersant and group II base oil to give final concentrate that contains 2.5 Wt % Zn. This method of making dispersion is Mixing approach.
Heat-Cool-Heat Cycle Method
[0000]
The concentrate prepared in the above example 7a was mixed with group II base oil to give final blend containing Zn metal concentration of 500 ppm and the blend was heated to 230° C. soaked for 5 min at heating rate of 10-20K/min and cooling down normally to -20° C. then heated again to 230° C. This heat-cool-heat cycle was also performed for ZnO blend made from concentrate prepared via in situ method by example 2.
EXAMPLE 8
[0059] Comparative data for comparing the stability of ZnO prepared by ex situ preparation method and in situ preparation method according to the present invention and Heat-Cool-Heat cycle test data of ZnO prepared by ex situ preparation method and in situ preparation method according to the present invention.
[0000]
TABLE 3
The storage stability and clarity of ex situ/mixing and in situZnO
dispersion and accelerated stability between in situ and ex situ
prepared ZnO dispersion.
Accelerated
Storage
Stability,
stability for a
Heat-Cool-Heat
week*
Dispersion clarity*
Cycle*
Ex situ/Mixing
In situ
Ex situ/Mixing
In situ
Ex situ
In situ
2/1
5
1/1
5
2
5
*Rating given in 5 points scale; 5—excellent, 4—very good, 3—good, 2—fair, 1—below fair.
(a) Comparison of standard Lattice plane and the calculated lattice plane for PXRD indicating the complete conversion to ZnO;
[0000]
TABLE 4
Lattice spacing, d (Å)
PXRD
Standard
HRTEM
ZnO
LBZ heated at 150° C./6 h
LBZ heated under vacuum in Oil
2.8143
2.8194
—
2.6033
2.6069
2.5900
2.4759
2.4798
—
[0060] The additive concentrate of the present invention is a greener or environmentally benign and would be compatible with depolluting systems or emission treatment system in the engine tail. Zn containing concentrate or oil composition would replace partially or completely organo S and P based ZDDP as an antiwear additive and thus it would be mixed with lubricant formulation where low SAPS are desired. | The present invention relates to a process for synthesizing dispersion of ZnO nanoparticles in an oil medium. Particularly, the invention relates to a process for in-situsynthesis of dispersion of ZnO nanoparticles in oil medium. Additionally, the present invention relates to a lubricant oil composition, wherein the composition comprises a base oil, a dispersant and the dispersion of ZnO as obtained by the process of the present invention. | 1 |
BACKGROUND AND SUMMARY OF INVENTION
This invention relates generally to a model building kit and more particularly concerns a building kit for a model railroad with interchangeable modular units which provide the builder with a means of tailoring the building to the builder's specifications for a more realistic appearance.
Model railroading has become increasely popular in recent years. The hobby has expanded well beyond the traditional children's toy, developing to a level of expertise where many adults are expending much time and money in building accurate reproductions of the trains and their surroundings. Many of the landscapes used by the builders reflect the buildings of the late nineteenth century through the early to mid-twentieth century when the railroads were at their peak of popularity. Since trains were often used in conjunction with heavy industry, it is common for industrial sites, such as factories and warehouses, to be included in the model train's landscape.
In order for the hobbyist to build realistic landscapes, he must construct buildings accurately portraying the architecture of the time period. To model train enthusiasts, one important factor which distinguishes the model train set as a realistic reproduction from a prefabricated toy is the amount of detail in the buildings and authenticity of the architecture. In the past, to achieve the desired detail, many hobbyists would erect model buildings by cutting and gluing raw materials together. The assembly of a building from raw materials, such as balsa wood, allows the hobbyist to create any style, shape and size building, and further provides the hobbyist with as much detail and creativity as his ability will permit. The assembly of such a building is very time consuming, however, especially when building a large warehouse of factory, and requires a high level of skill to construct with the required detail.
Another option open to the hobbyist is to buy a prefabricated model kit, which are easy to assemble and do not require the high level of skill or the amount of time required when building from raw materials. Model kits are designed to be erected as one specific building, however, which requires the builder to tailor the train layout around the building. Further, the kits do not allow the builder the needed creativity when designing authentically appearing landscapes. One of the easiest ways to make a model railroad look inaccurate is to use a building kit just as it is shown on the box, particularly if the model is made of injection molded plastic. Any experienced modeler can spot a mass produced kit at a glance. Hence, the time saved by using a kit is at the sacrifice of both realism and credibility. To avoid this pitfall, many hobbyists rely on a practice known as "kit bashing", where the hobbyist will purchase one or more hobby sets and modify the structure to meet his needs. While "kit bashing" provides the hobbyist with a wider range of creativity, it also increases the difficulty of assembling the desired building.
Therefore, there is a real need in model railroading for a model building kit that provides the builder with the realism and flexibility of building from raw materials and the convenience of a prefabricated kit.
In accordance with the present invention, as depicted in the drawings and described in more detail below, a model building kit is provided comprising interchangeable wall panels, which when assembled, form an accurate scale replica of an industrial building. Because the wall panels are interchangeable, a wide variety of building shapes and sizes may be erected. The kits, in one embodiment, will include enough of the wall panels to create either a complete building or a false facade. Since many builders have a limited area in which to construct the landscape, they must rely on the false facade. The architecture of the model building reflects a popular style of architecture used in the construction of factories and warehouses during the early to mid-twentieth century. The kit, in one embodiment, is built to 1:87 scale, otherwise known as H.O. scale in model railroading.
The wall panels are comprised of interchangeable sub-units. The sub-units are, in one embodiment, manufactured in injection molded plastic and colored during the manufacturing process so the building does not require painting. The interchangeable sub-units comprise windows, spandrels, sills, doors and foundations which allow the builder to design each wall to his individual needs. The claimed invention, in one embodiment, has slightly taller first floor panels to incorporate the building's foundation for proper authenticity. In this embodiment, the first floor panels are not interchangeable with the upper floor panels, but this is not of concern since a typical kit will include enough panels so there is no need to use the first floor panels on the upper floors.
The wall panels interconnect so when stacked upon one another, no seam is visible from the exterior of the building. The kit may further provide wall panels to construct a penthouse which is placed on top of the model building.
The wall panels are vertically connected by columns which are also interchangeable and comprised of three basic forms: straight wall columns, outside corner columns and inside corner columns, with the columns corresponding to the first floor panels being slightly longer to incorporate the foundation. The columns and the wall panels support a roof panel. The roof panel has a grid pattern notched into one side with the distance between the grids equal to the length of a wall panel. The roof may be cut along the grid pattern to conform to any size or shape building desired. The roof panel further may be used in the interior of the building as a floor so that the builder may add detail to the interior of the building.
It is, therefore, an object of the present invention to provide the model builder with a relatively simple to assemble, authentic model building kit which has enough detail to satisfy the needs of a model train enthusiast as to authenticity.
It is another object of the present invention to provide a model building kit which allows the builder to tailor the building's size and shape to meet his individual needs.
Further, it is an object of the present invention to provide the builder of the model kit an accurate reproduction of an early twentieth century factory or warehouse that does not require painting after assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which:
FIG. 1 is a perspective view and assembly of the brick facing attached to the sill wall;
FIG. 2 is a perspective view and assembly of a window wall panel to be used on the first floor of the building;
FIG. 3 is a perspective view and assembly of a window wall panel for the upper stories of the building;
FIG. 4 is a perspective view and assembly of the wall panel corresponding to the elevator shaft;
FIG. 5 is a perspective view and assembly of a wall panel containing one door;
FIG. 6 is a perspective view and assembly of a wall panel containing delivery doors;
FIG. 7 is a perspective view and assembly of a wall panel containing a door corresponding to the penthouse;
FIG. 8 is a perspective view and assembly of a wall panel containing delivery doors;
FIG. 9 is a perspective view and assembly of a wall panel containing windows and a door;
FIG. 10 is a perspective view and assembly of the penthouse;
FIG. 11 is a perspective view and assembly of the wall panels, columns and parapet;
FIG. 12 is a side view of the interconnection of the wall panels:
FIG. 13 is an enlarged perspective view and asembly of the columns and walls panels;
FIG. 14 is a sie view of the interconnection of columns, column cover and roof panel;
FIG. 15 is a perspective view and assembly of the outer corner columns and column cover;
FIG. 16 is a perspective view and assembly of the inside corner columns and column cover;
FIG. 17 is a perspective view of one embodiment of the building with the roof being assembled;
FIG. 18 is a perspective view of the building and assembly of column covers and the penthouse;
FIG. 19 is a perspective view of possible building design of the claimed invention;
FIG. 20 is a perspective view of possible building design of the claimed invention.
While the invention will be described in connection with the preferred embodiment, it will be understood that it is not intended to limit the invention to that embodiment. To the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings, FIG. 1 shows the assembly of the brick facing 10 to the sill panel 12 to form the sill wall 11 which, in a typical kit, thirty assemblies are required. The model kit is assembled by using any bonding agent, such as glue or epoxy, that will hold the units together. The brick facing 10 is colored and textured to resemble the brick used in an early twentieth century factory, and the sill panel 12 is colored to resemble concrete. The sill wall 11 is one of the basic pieces of the invention which gives the claimed invention its interchangeablity and authentic appearance. The kit, in the preferred embodiment, is designed to the H.O. scale used in model railroading, or 1:87, but can just as easily be designed to any necessary scale.
FIG. 2 depicts the assembly of a first floor wall panel 14 which is comprised of the window frame 16, brick facing 10, first floor sill panel 18 with foundation 19 and spandrel beam 20. The brick facing 10 is secured to the first floor sill panel 18 which is then attached to the lower portion of the window frame 16. The spandrel beam 20, which corresponds to the location of the upper floors of the building and the roof panel 88, is added to the upper portion of the window frame 16 to form the first floor wall panel 14. The beam 20 further has tabs 21 which support the roof panel 88. Because of the foundation 19, this panel 14 is to be used on the first floor only, and is slightly taller than the wall panels to be used on the upper floors. In a typical kit, eight such assemblies are required. FIG. 3 depicts the assembly of a window panel 22 which utilizes the same window frame 16 as used in FIG. 2, but is to be used on the upper floors. The assembly of the sill wall 11, from FIG. 1, is attached to the lower portion of the window frame 16 and the spandrel beam 20 is attached to the upper portion of the window frame 16. Fifteen such assemblies are required. To conform with the H.O. scale, the wall panels are 67.5 millimeters in length (L), 41.4 millimeters in height (H) on the upper floors and 43.9 millimeters in height (H') for the first floor.
FIGS. 4 and 5 depict the assembly of the wall panels 24 and 30 which represents the location of the elevator shaft within the building. The window 26 and spandrel beam 20 are attached to the corresponding openings in the brick wall sill 28 to form the wall panel 24. The wall panel 30 is assembled by attaching the door 32, foundation 36 and spandrel beam 20 to the brick wall sill 34. One assembly of wall panel 30 and three asemblies of wall panel 24 are required.
The wall panel 38, as depicted in FIG. 6, represents the main delivery doors to the factory. The panel 38 is assembled by attaching the foundations 40, brick facings 42 and spandrel beam 20 to the delivery door panel 44. Note that there is no foundation under the delivery doors so that, in the original building, heavy equipment may enter the factory through the doors. In a typical kit, two such assemblies are required. FIG. 7 depicts the assembly of the wall panel 48 which contains the door leading from the roof into the penthouse 74 containing the elevator equipment. The panel 48 is the only wall panel with a door and without a foundation, since the panel is only to be mounted on the roof and is assembled by attaching door 50 to wall unit 52. One such assembly is required.
FIG. 8 depicts the assembly of the wall panel 54 which corresponds to a combination delivery door and employee entrance door wall panel. Panel 54 is assembled by attaching foundation 56, doors 58, 60, and spandrel beam 20 to wall unit 62. One such assembly is required. FIG. 9 depicts the assembly of a combination window and door wall panel 64 possibly corresponding to an office located within the building. The panel 64 is assembled by attaching brick facing 66 to the sill panel and foundation 68 to form a sill wall 69 and brick facing 42 and spandrel panel 20 to door and window unit 72. Two such assemblies are required.
FIG. 10 decipts the assembly of penthouse 74 by attaching wall panel 24 from FIG. 4 and the wall panel 48 from FIG. 7 with wall units 76 and outer corner columns 78. The roof unit 80 is attached to the top of penthouse 74 and penthouse roof panel 82 is inserted within panel 80.
FIG. 11 is a view of the assembly of wall panels 14 and 22 from what will be the interior of the building. It should be noted that the panel 14 has a foundation 19 so that it can only be used on the first floor. The sill wall 11 assembly from FIG. 1 is used as the parapet 13 of the building, which is attached to the wall panel 22 and protrudes above the roof panel 88.
FIG. 12 is an enlarged side view depicting the interconnection of wall panels 14 and 22. The wall panel 14 rests upon foundation 19 which is part of first floor sill panel 18 and brick facing 10 is shown attached to the outwardly facing portion of first floor sill panel 18. The window frame 16 is attached to the sill wall 18 and supports spandrel panel 20 to form wall panel 14. The sill panel 12 and brick facing 10, which forms the sill wall 11, is attached to the window frame 16 to form wall panel 22. The wall panel 22 is secured to the top of the wall panel 14 at the spandrel beam 20. It should be noted that since the sill panel 12 does not have a foundation, the brick facing 10 rests flush with spandrel beam 20 and sill panel 12 abuts the rear portion of spandrel beam 20. Because of the interconnection between am the sill wall 11 and spandrel beam 20, no seam is visible between brick facing 10 and the spandrel beam 20 from the exterior of the building. This assembly represents the interconnection of all first floor panels to upper floors panels, the upper floor wall panels to each other and the parapet 13 to the top floor wall panel.
Referring again to FIG. 11, the wall panels 22 and 14 are supported vertically by straight wall columns 83 and 84, outer corner columns 77 and 78 and interior corner columns 86 and 87. FIG. 13 is an enlarged view of the assembly of the straight wall columns 83 and 84 and column cover 85 to wall panel 22 and parapet 13. The wall panel 22 has a notched portion 23 which runs along its vertical edge to accommodate the column 84 and parapet 13 has an identical notch portion 23 which engages column cover 85. It should be noted that while only wall panel 22 and parapet 13 are shown, all wall panels have notched portions 23 in their vertical sides which engage the columns and provide structural support. Column 84 has a tab portion 91 which corresponds to an opening 92 in the top of column 83. Column cover 85 has a similar tab 91 which corresponds to an opening 92 to the top of column 84. The tab portions 91 and openings 92 interconnect to furtgher support the columns. FIG. 14 is a side view taken along line 14 of columns 83, 84 and column cover 85. The side view depicts how tab 91 engages the opening 92 to interconnect the columns. The columns further have a U-shaped member 90 which supports the roof panel 88. The column cover 85 is further supported by the roof panel 88.
FIG. 15 is an enlarged view of the outer corner columns 77 and 78, and corner column cover 75. The columns 77 and 78, and cover 75 have a sawtoothed edge 79 to engage the notched portions 23 in the wall panels. Also, column 78 and cover 75 have L-shaped tabs 94 which corresponds to an L-shaped notch 93 in columns 77 and 78 which interlock the columns together.
FIG. 16 shows the assembly of interior columns 86 and 87 with column cover 96. The columns 86 and 87 have a square cross-sectional shape which corresponds to the notch portions 23 in the wall panels.
FIG. 17 is a view of one assembly of the building with the wall panels and parapet 13 in place with the roof panel 88 being attached. Roof panel 88 rests upon U-shaped member 90 and tabs 21 in spandrel beam 20. The panel is notched in a grid pattern 89 which corresponds to the length of each wall panel. The grid pattern allows the builder to cut the roof panel to conform to whatever shape building is desired.
FIG. 18 depicts the assembly of column covers 75 and 85 and penthouse 74. It is important to note that, to create an accurate reproduction, the penthouse 74 should be placed in alignment with wall panels 24 and 30 which will represent the location of the elevator shaft within the building. Further, no parapet is to be placed above wall panel 24 because penthouse 74 is to be attached in alignment with wall panel 24. FIGS. 19 and 20 show various assemblies that can be made from one typical kit. FIG. 19 shows a three-story building with a one-story lower entrance portion, generally designated 98. It should be noted that the roof panel 88 may be cut and separated to form a multiple story building. FIG. 20 depicts a building, generally designated 99, in which an underpass 100 has been designed in the building. In this design, the roof panel 88 has been cut into an L-shape, showing again the versatility of the claimed invention, and more particularly the roof panel 88. The roof panel 88 may also be used as the ceiling panel under the overhang. Moreover, building 99 has incorporated interior column 87 and column cover 95 at the interior corner 101 adjacent to the inderpass 100.
Thus, it is apparent there has been provided, in accordance with the invention a model building kit that satisfy the objects, aims and advantages set forth above. While this invention has been described in conjunction with the specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and broad scope of the appended claims. | A model building kit deploying interchangeable wall panels in order to create a variety of building designs. The model building kit includes wall panels made up of interchangeable sub-units which further allows the builder to conform each individual panel to his needs. The wall panels interconnect with one another and are vertically supported by columns. The columns support a roof panel which may be also used in the interior of the building as floors. The style of architecture of the model kit is that of an industrial building such as a factory or warehouse. | 0 |
CROSS REFERENCE To RELATED APPLICATION
[0001] The Present Disclosure claims priority to U.S. Provisional Patent Application No. 61/839,414, entitled “Thermal Interposer Suitable For Electronic Modules,” and filed 26 Jun. 2013 with the United States Patent And Trademark Office. The content of this Application is incorporated in its entirety herein.
[0002] The Present Disclosure claims the benefit of U.S. Provisional Patent Application No. 61/839,412 (Molex Docket No. B2-022 US PRO), entitled “Ganged Shielding Cage With Thermal Passages,” filed on the same day as the priority claim listed above, the content of which is hereby incorporated herein.
[0003] Finally, the Present Disclosure also claims the benefit of Co-Pending U.S. Patent Cooperation Treaty Patent Application No. ______ (Molex Docket No. B2-022 WO), entitled “Ganged Shielding Cage With Thermal Passages,” filed on the same day as the Present Disclosure, the content of which is hereby incorporated herein.
BACKGROUND OF THE PRESENT DISCLOSURE
[0004] The Present Disclosure relates, generally, to thermal solutions to heat transfer of electronic modules, and, more particularly, to a thermal interposer having improved contact characteristics to improve heat transfer between an electronic module and a heat sink.
[0005] There are many different styles of heat sinks used in the field of electronics. In many electronic devices, such as routers, servers and the like, different sets of circuits need to connect to associated circuits of other electronic devices. This is commonly accomplished by way of cable assemblies that typically include an electronic module terminated to each end of the cable. The modules serve to connect the cable to a corresponding connector on a circuit board within the device and with respect to routers and servers, these cable assemblies operate at high data transfer speeds, the operation of which generates heat.
[0006] Heat sinks are utilized to transfer heat generated by the module to the exterior of shielding cage in which the module is inserted. Most of these heat sinks are applied directly to the surface of the module and thus require particular configuration for each module. Others rely upon a thermal interface material, referred to as a “TIM,” and these TIM materials increase the thermal resistance of the overall assembly, as well as the cost. Other heat sinks are rigidly attached by adherent materials, such as solder, which may add to the overall thermal resistance and also may affect the structural and mechanical operation of the attachment. Solder also creates problems with certain materials used in heat sinks, such as aluminum as oxide barrier may form on the aluminum during soldering. Still further, due to the dissimilarity of solder with aluminum, galvanic corrosion may occur in the finished heat sink.
[0007] Some have developed a thermal interposer that utilizes a plurality of cantilevered contact arms arranged in a pattern on the interposer. The interposer is rigidly attached to the heat sink by soldering, which inhibits the contact arms from operating in an elastic manner. This rigid attachment results in a permanent set across the face of the interposer and induces plastic strain in the contact arms. This plastic strain does not promote good Hertzian contact, and diminishes the elasticity of the contact arms. When this occurs, the normal force between the contact arms and the opposing surface of the module is reduced.
[0008] The Present Disclosure is therefore directed to an improved thermal interposer that does not require a continuous rigid attachment and which is particularly suitable for use with electronic modules, the interposer having an attachment structure that retains a reliable normal force and good Hertzian contact between the interposer and the electronic module.
SUMMARY OF THE PRESENT DISCLOSURE
[0009] Accordingly, there is provided a thermal interposer suitable for electronic module applications, providing a reduced cost structure for attachment to a heat sink and further providing reliable, beneficial contact between the interposer and the electronic module. In accordance with an embodiment of the following Present Disclosure, a thermal interposer is provided for positioning between a heat sink and an electronic module and the interposer is provided with a structure that permits good, reliable contact with both the heat sink and the module, without the need to use any thermal interface material.
[0010] The interposers of the Present Disclosure are formed from a flat plate-like member that has a width matching or exceeding to some extent, the width of the electronic module. On one surface of the module, preselected, discrete portions of the plate-like member are bent upwardly. These bent portions define a series of pegs or the like that are configured to fit within selected grooves, or channels, that are formed in the bottom surface of a heat sink member. Such a fit is a press fit attachment accomplished with high mechanical pressure, creating in effect, a solid joint between the interposer pegs and the heat sink. Such a joint has low thermal resistance, much lower, and typically minimal, at best, than that obtained using a thermal interface material. The press fit application also serves to remove oxides from the aluminum surfaces of the heat sink grooves which would otherwise increase the thermal resistance and thereby improves heat transfer between the heat sink and the module, by way of the interposer.
[0011] The press-fit pegs eliminate the need for a continuous rigid manner of attachment of the interposer to the heat sink. This is important because the interposer has a series of cantilevered contact arms stamped, or otherwise, formed therein and these contact arms have their free ends bent downwardly toward an opposing surface of the electronic module. These arms are intended to be elastic and they remain so due to the press-fit attachment. If the interposer were to be rigidly attached to the heat sink, such as by way of solder, welding or the like, the solder would form an attachment to the contact arms, especially near the radius around which the contact rams flex. The presence of the continuous rigid attachment would cause the contact arms to become plastic, rather than elastic, and this condition would inhibit the application of reliable normal forces by the contact arms onto the module surface.
[0012] The press-fit pegs are arranged in a pattern that separates them into two distinct groups. A first group of such pegs are arranged around a portion of the perimeter of the interposer body portion and in one embodiment described herein, along two opposing, longitudinal edges of the interposer. The second group of press-fit pegs are disposed interior of the perimeter and are arranged between adjacent rows of contact arms. The base portion of the press-fit pegs are arrange longitudinally as are the contact arms but the press-fit pegs have their base portion oriented perpendicular to the based portions of the contact arms. In this manner, as described in one embodiment of the Present Disclosure, a series of L-shaped heat transfer paths are defined between pairs of associated press-fit pegs and contact arms.
[0013] These and other objects, features and advantages of the Present Disclosure will be clearly understood through a consideration of the following detailed description.
BRIEF DESCRIPTION OF THE FIGURES
[0014] The organization and manner of the structure and operation of the Present Disclosure, together with further objects and advantages thereof, may best be understood by reference to the following Detailed Description, taken in connection with the accompanying Figures, wherein like reference numerals identify like elements, and in which:
[0015] FIG. 1 is a perspective view of a single electronic module, in place within one bay of a ganged shielding cage, utilizing an interposer constructed in accordance the Present Disclosure;
[0016] FIG. 2A is a perspective view, taken from the bottom of the shielding cage-module assembly of FIG. 1 , with the bottom and some of the side walls of the shielding cage removed for clarity, along with the bottom half of the electronic module;
[0017] FIG. 2B is the same view as FIG. 2A , but with the electronic module removed for clarity and illustrating the thermal interposer in place on the bottom surface of the heat sink;
[0018] FIG. 3A is the same view as FIG. 2B , but with the cage side wall removed and enlarged to illustrate the array of contact arms formed on the thermal interposer;
[0019] FIG. 3B is a front elevational view of the thermal interposer in place upon the heat sink and illustrating the manner of connection therebetween;
[0020] FIG. 4A is a perspective view of the thermal interposer taken from the bottom surface thereof;
[0021] FIG. 4B is a perspective view of the thermal interposer of FIG. 4A , but in an inverted fashion, illustrating the top surface thereof with the heat sink engaging pegs;
[0022] FIG. 4C is a top plan view of the thermal interposer of FIG. 4A ;
[0023] FIG. 4D is a side elevational view of the thermal interposer of FIG. 4A , along Line D-D;
[0024] FIG. 4E is an end elevational view of the thermal interposer of FIG. 4A , along Line E-E;
[0025] FIG. 4F is an enlarged perspective view of a single contact arm used in a known interposer attached to the heat sink rigidly by way of solder in the shaded area; and
[0026] FIG. 4G is an enlarged view of a contact arm used in the interposers of the Present Disclosure attached to the heat sink by way of the attachment members.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] While the Present Disclosure may be susceptible to embodiment in different forms, there is shown in the Figures, and will be described herein in detail, specific embodiments, with the understanding that the Present Disclosure is to be considered an exemplification of the principles of the Present Disclosure, and is not intended to limit the Present Disclosure to that as illustrated.
[0028] As such, references to a feature or aspect are intended to describe a feature or aspect of an example of the Present Disclosure, not to imply that every embodiment thereof must have the described feature or aspect. Furthermore, it should be noted that the description illustrates a number of features. While certain features have been combined together to illustrate potential system designs, those features may also be used in other combinations not expressly disclosed. Thus, the depicted combinations are not intended to be limiting, unless otherwise noted.
[0029] In the embodiments illustrated in the Figures, representations of directions such as up, down, left, right, front and rear, used for explaining the structure and movement of the various elements of the Present Disclosure, are not absolute, but relative. These representations are appropriate when the elements are in the position shown in the Figures. If the description of the position of the elements changes, however, these representations are to be changed accordingly.
[0030] FIG. 1 illustrates a partial shielding cage 10 typically mounted to a circuit board 11 . The shielding cage 10 is of the ganged type, meaning it has a plurality of bays 12 defined therein between side walls 14 of the cage. Each bay 12 is configured to receive an electronic module 15 therein that provides a connection between a cable containing a plurality of wires (not shown) and a connector mounted to the circuit board 11 and disposed within the bay 12 of the cage 10 . The electronic module 15 may be designed for high speed data transmission and as such, generates heat during its operation. This heat must be dissipated and therefore a heat sink 16 is provided that either lies on top of the cage 10 , or forms a top wall, or ceiling 17 , thereof.
[0031] As illustrated in FIG. 29 , an interposer, or leadframe, 20 is provided for the bay 12 in which the module 15 resides. The module 15 is shown removed in FIG. 2B , as is the cage bottom, for clarity. The interposer 20 can be seen to have an elongated body portion 21 , illustrated as a rectangle in the Figures. The interposer has a plurality of side edges 22 a - d that cooperatively define the body portion 21 . The interposer further has two opposing surfaces, shown as top and bottom surfaces 23 , 24 , respectively and these surfaces make contact with the heat sink 16 and the electronic module 15 as explained in further detail below.
[0032] In order for the interposer 20 to function as a thermal interposer—that is, one that transfers heat from the module 15 to the heat sink 16 the interposer 20 is firstly provided with a plurality of contact members, illustrated as cantilevered contact arms 25 that may be stamped and formed in the interposer body portion. These contact arms 25 are defined by U-shaped openings 26 formed in the interposer body portion; three parts of the openings 26 provide the cantilevered configuration to the contact arms 25 . The contact arms 25 have elongated base portion 27 aligned lengthwise within the interposer body portion 21 , and which terminate in free ends 28 , which may be coined, or otherwise treated, to form. contact surfaces 29 at the free ends. In use, these contact surfaces 29 make contact with the top surface 15 c of the electronic module 15 .
[0033] A plurality of attachment members 30 are disposed on the other (top) surface of the interposer. These attachment members 30 are illustrated as press-fit pegs 32 having base portions 33 where they are bent up from the interposer body portion. These base portions 33 terminate in pointed ends 34 having a generally triangular configuration, although other configurations may be suitable. The interior attachment members 30 have U-shaped openings that define their shape and permit them to be bent out of the plane of the interposer body portion into the desired upright shape. These attachment members 30 are configured to be received within grooves 40 formed in the bottom surface 16 b of the heat sink 16 . The pointed ends 34 of the attachment members 30 permits the attachment members to be reliably inserted into the heat sink grooves 40 in such a manner that good and intimate metal-to-metal contact is made, with good heat transfer capabilities and low thermal resistance properties, about equal to that Obtained from a solid attachment. Thus, it is preferred that the attachment members 30 are slightly thicker than the width of the heat sink grooves 40 .
[0034] As shown in the Figures, the grooves 40 run lengthwise within the heat sink 16 and the spacing between the grooves 40 defines an intended spacing between the attachment members 30 . It can be seen that the contact arms are arranged on the interposer body portion in a manner that defines a plurality of rows, running both lengthwise and crosswise (transversely) within the perimeter of the interposer 20 . The attachment members 30 are arranged in what may be considered as two distinct groups of attachment members 30 . The first group of attachment members 30 are those that are disposed substantially around the perimeter of the interposer, shown as positioned on side edges 22 a, 22 b, 22 c in FIG. 4C and will be referred to herein as an “exterior” group of attachment members 30 .
[0035] The second group of attachment members 30 are those remaining members disposed inwardly from the side edges of the interposer and will be referred to herein as an “interior” group of attachment members 30 . The interior attachment members 30 are disposed in rows that are positioned between rows of contact arms in FIG. 4C . As such, the interior attachment members serve to divide the contact arms 25 into groups. In FIG. 4C , two imaginary lines LA and CA are drawn in respective longitudinal and crosswise directions, interconnecting interior attachment members for the CA line and both interior and exterior attachment members for the LA line. The CA lines define crosswise rows of contact arms, while the LA lines define lengthwise rows of contact arms 25 . Cooperatively, the lines define imaginary boxes CAB that surround groups of contact arms 25 . These groups can either be arranged in the lengthwise or crosswise direction. Likewise, the imaginary lines separate adjacent contact arms 25 from each other. Still further it is preferred that the interior attachment members 30 are disposed close to where the contact arm body portions meet the interposer body portion. As illustrated, the location of the attachment members 30 with respect to the contact arms defines a series of individual thermal transfer paths “TP” between associated pairs of contact arms and attachment members 30 . As shown, the thermal transfer paths are L-shaped.
[0036] The structure of this interposer and the grooves of the heat sink provide for a semi-rigid attachment of the interposer that differs from other rigid attachment structures, such as solders. With interposers 20 of the Present Disclosure, heat generated within the module 15 is transferred to the interposer 20 by way of conduction between the contact arms 25 and the interposer body portion 21 . The heat then travels from the interposer body portion 21 to the attachment members via the thermal transfer paths TP, and into the body of the heat sink by way of contact with the walls of the heat sink grooves 40 . Most heat sinks 16 are made out of aluminum, which is prone to oxidation, and the use of dissimilar metals promotes galvanic corrosion. The oxidation that occurs on aluminum surfaces makes soldering difficult and moreover, increases the thermal resistance of the overall structure, as does any thermal interface material such as adhesive, tape, gap filling pads, etc. Still further, as shown in FIG. 4F , a solder attachment method creates problems with the contact arms of such an interposer in that the body portion of the interposer and part of the base of the contact arm are attached to the heat sink as shown in the shaded area of FIG. 4F . Because of this area of attachment, plastic strains will occur along the entire width of the contact arm where it is joined to the body of the interposer, at arrow Z. Deflection of the interposer contact arms in this structure when the module is inserted into the shielding cage bay will cause plastic strain and the contact arm no longer becomes entirely elastic. This will detrimentally affect the normal forces required between the contact arms and the electronic module top surfaces.
[0037] Utilizing interposers of the Present Disclosure eliminates these problems. The plastic strains which occur in the interposer contact arms occur in the body portion 21 of the interposer 20 as shown by Arrow Z in FIG. 4G , thereby reducing, if not altogether eliminating, permanent set in the contact arms. This will maintain the normal force applied by the contact arms in the range desired by the designer to achieve good Hertzian contact. The attachment between the interposer and the heat sink is metal-to-metal and thus there is an overall reduced thermal resistance.
[0038] While a preferred embodiment of the Present Disclosure is shown and described, it is envisioned that those skilled in the art may devise various modifications without departing from the spirit and scope of the foregoing Description and the appended Claims. | A thermal interposer for use in providing a mating interface between a heat sink and an electronic module includes an elongated body portion having two opposing surfaces. On one surface, a plurality of press-fit pegs are defined that extend upwardly and outwardly away from the interposer body portion. On the other, opposing surface, a plurality of contact arms are defined that extend, in cantilevered fashion, downwardly and away from the interposer body portion. The press-fit pins are configured to enter grooves formed in a heat sink in a manner to form intimate, metal to metal, contact while the contact arms are configured to contact the top surface of an electronic module with reliable normal force. | 7 |
FIELD OF INVENTION
[0001] This invention relates to a wall system. A particularly preferred form of the invention relates to a wall system which can be used in the context of transportable buildings.
BACKGROUND
[0002] It is known from New Zealand patent No. 532620 (in the name Habode IP Limited) to create a building which can be shipped in the manner of a freight container. The building can then be assembled on site. Installation may involve swinging a floor and a roof outwards from a housing by way of pivot connections. More specifically, the floor may swing down and the roof may swing up. When the floor and roof have been arranged in this way it is desirable to create a wall therebetween. It is accordingly an object of at least one form of the present invention to go at least some way towards facilitating this, or to provide the public with a useful choice. While reference has been made to New Zealand patent No 532620, it should be understood that the present invention is not limited to buildings described in that document.
[0003] The term “comprising” or derivatives thereof, if and when used in this document should not be interpreted to exclude the possibility of other features.
SUMMARY OF THE INVENTION
[0004] According to one aspect of the invention there is provided a method of constructing at least a part of an external weatherproof wall of a building comprising the steps of:
i) obtaining a structural post which has a first slot running along one side thereof and a second slot running along an opposite side thereof, the slots facing substantially different directions, ii) obtaining a wall panel which has a first edge part and second edge part, each edge part opposite the other, iii) arranging the post so that it is substantially vertical between a roof and a floor with its slots running substantially vertically, and securing the post in that disposition, iv) arranging the wall panel so that its first edge part is fitted in the first slot in a watertight manner, v) obtaining a second structural post with slots substantially the same as for the first mentioned post and arranging and securing it between the roof and floor so that one of the slots of that second post receives the second edge part of the panel in a watertight manner, vi) arranging a second panel with edge parts substantially the same as those of the first mentioned panel so that one of the edge parts of that second panel is within the other slot of the second post to create a watertight fit therebetween, and vii) repeating steps v) and vi) with but using further posts having substantially similar slots and further panels having substantially similar edge parts to substantially create the wall or part thereof,
the wall being such that it can be disassembled without the application of destructive force to the panels or posts.
[0012] Preferably the posts are secured to the roof and floor with fixing members (eg bolts) and the panels are fitted to the posts without fixing members.
[0013] Preferably the slots of the posts and the edge parts of the panels are complimentary to enable female/male fitting therebetween.
[0014] Preferably the roof has a generally down facing channel, and an upper part of each post and/or an upper part of each panel is fitted into that channel.
[0015] Preferably upper ends of the posts and/or panels are fitted into the channel of the roof and then swung downwards until they are substantially vertically oriented.
[0016] Preferably the channel is generally “ ” shaped.
[0017] Preferably the posts and/or panels are swung downwards onto an extrusion forming part of the floor after engaging the roof.
[0018] Preferably the floor has a generally shaped extrusion and a lower part of each post and a lower part of each panel is fitted against that extrusion.
[0019] Preferably strips of sealing material are used to achieve watertight fittings between the panels and posts, and/or between the panels and the roof and floor, and/or between the posts and the roof and floor.
[0020] Preferably the building can be disassembled and parts of the roof and floor swung inwards about hinges so that the building assumes the shape of a shipping container.
[0021] According to a further aspect of the invention there is provided a weatherproof wall or part thereof formed according to a method as set out above.
[0022] According to a further aspect of the invention there is provided a kit of parts suitable for forming a weatherproof wall or part thereof by way of the method as set out above, the kit comprising the posts and panels, and optionally the channel and/or the extrusion.
DESCRIPTION OF THE DRAWINGS
[0023] Some preferred forms of the invention will now be described by way of example and with reference to the accompanying drawings, of which
[0024] FIG. 1 is a perspective view of a portable building in a disassembled state ready for shipping in the manner of a freight container,
[0025] FIG. 2 is a perspective view of the building in a partially assembled state,
[0026] FIGS. 3 & 4 are perspective views showing opposite sides of the building when fully assembled,
[0027] FIG. 5 is a perspective view of a panel used in assembling the building,
[0028] FIG. 6 provides elevation views of various optional panels for use in the building,
[0029] FIGS. 7 & 8 illustrate the way panels may be erected to form a wall of the building,
[0030] FIGS. 9 & 10 show a channel forming part of the building's roof in cross section and in perspective respectively,
[0031] FIGS. 11 & 12 show a channel forming part of the building's floor in cross section and in perspective respectively,
[0032] FIG. 13 is a perspective view of a medial post forming part of the building,
[0033] FIG. 14 is a perspective view detailing part of the medial post,
[0034] FIG. 15 is a transverse cross section view of the medial post,
[0035] FIG. 16 shows perspective and cross sectional detail of a particular panel forming part of the building,
[0036] FIG. 17 is a perspective view showing detail of the way that the panel engages the floor of the building, and
[0037] FIG. 18 is a transverse cross section showing a corner post of the building fitted with panels substantially at right angles to one another.
DETAILED DESCRIPTION
[0038] FIG. 1 shows a portable building 1 in a disassembled state, substantially arranged as a 40 foot shipping container which conforms to ISO standards. When in its FIG. 1 configuration the building 1 can be shipped as an upper or lower part of a stack of containers, and is thus able to withstand substantial compressive force. FIG. 2 shows the building 1 in a partially assembled state with roof 2 and floor 3 extensions proceeding outwards from a central part 4 . When the building is in the container configuration shown in FIG. 1 the roof 2 and floor 3 extensions overlap one another at each side of the container. To achieve the FIG. 2 arrangement these roof 2 and floor 3 extensions are swung up and down respectively by way of a series of hinges 5 . As shown in FIG. 2 , corner posts 6 may be bolted in place to hold the floor and roof 3 extensions with respect to one another.
[0039] When in a fully assembled state the building 1 may appear as shown in FIGS. 3 and 4 , complete with a sun shade 7 and decking 8 . The external walls of the building are created from a series of panels 9 and end and medial posts 6 , 10 . As shown, some of the panels incorporate windows and some do not. The pattern in which these panels 9 are employed will depend on the requirements and preferences of the end user.
[0040] FIG. 5 shows one of the panels 9 in more detail and FIG. 6 shows various other options for the panels in terms of size and shape. FIGS. 7 and 8 exemplify the way in which panels 9 and medial posts 10 are installed, either before or after the corner posts 6 are set in place. Referring to FIG. 7 , a panel 9 (step 1 ) is taken and is angled (step 2 ) so that an upper edge 11 of the panel fits into a generally “ ” shaped upper channel 12 secured to the roof extension 2 (step 3 ). The profile of the channel 12 is shown in more detail in FIGS. 9 and 10 . The bottom edge 13 of the panel 9 is then swung down onto a lower extrusion or channel 14 which is generally shaped (step 4 ). The profile of the lower channel 14 , which is secured to the floor extension 3 , is shown in more detail in FIGS. 11 and 12 . The swing of the panel 9 down onto the lower channel 14 is interrupted when the panel is vertical by way of a water stop or ledge 15 (see FIGS. 11 and 12 ) forming part of the lower channel 14 . After the panel is vertically aligned between the upper and lower channels 12 and 14 it is slid sideways (eg to the left of the page) to butt up against one of the posts 10 (step 5 ).
[0041] Referring to FIG. 8 , a further post 10 ′ is then taken (step 6 ) and inserted between the upper and lower channels 12 and 14 , and then slid across to the panel 9 (steps 7 and 8 ), all in similar fashion to the way the panel 9 has been handled. Further panels and posts can be added in substantially the same way until the exterior wall of the building is complete. The arrangement is such that the sides of the posts 10 / 10 ′ provide ‘female’ slots for receiving complimentary ‘male’ edges of the panels 9 . These are fitted together in a water tight manner to prevent leaks into the interior of the building.
[0042] FIG. 13 provides more detail as to the profile of the medial posts 9 . As shown, each post 9 has a tongue 16 at its upper end, and a further tongue 17 at its lower end. These tongues are bolted to the upper and lower channels 12 and 14 respectively. FIG. 14 shows a portion of the post 9 in perspective and FIG. 15 shows the post in transverse cross section.
[0043] It is not essential to start an external wall of the building from any particular place, for example it can be commenced from a corner of the building or from a mid section of the building's perimeter. The roof section 2 may need to be supported in someway, for example by way of a small crane or the like, until enough posts/panels are installed to give sufficient structural integrity to keep the roof extension 2 up.
[0044] FIG. 16 provides detail of a preferred profile for the panels 9 . As can be seen, the vertical and horizontal framing 18 of the panel is adapted to accommodate double cladding, whether it be in the form of panes of glass 19 or non-transparent sheets 20 with insulation 21 therebetween. The non-transparent sheets are preferably formed from plywood laminated with a suitable ‘plastic aluminium’ substance. Further detail of the panel 9 and the way it associates with the floor extension 3 is shown at FIG. 17 . FIG. 18 provides detail of one of the corner posts when arranged between two panels 9 at right angles.
[0045] To assist in providing a water tight seal between the panels 9 and the rest of the building, the upper channels 12 are fitted with strips of rubber 22 pressed within generally ‘C’ shaped protrusions 23 (see FIGS. 9 and 16 ). As shown in FIG. 16 , the bottom parts of the panels are sealed with respect to the lower channel 14 by further rubber strips 24 . Rubber strips 25 or other suitable means are also employed to seal the panes of glass 19 and non-transparent sheets 20 with respect to the panel framing 18 . Additional rubber strips 26 (see FIG. 16 ) may also be employed to provide a water tight seal between the posts 6 , 10 and the panels 9 .
[0046] The posts 6 , 10 , the channels 12 , 14 and the panel framing 18 may all be formed as aluminium extrusions or the like. While the medial and end posts 10 , 6 have a different in transverse cross section their edge parts are preferably the same for receiving the panels 9 . By following the installation steps described above a watertight exterior wall can be created in a short time, employing a pattern of panels in terms or window positioning which suits the preferences of an end user. The manner in which the exterior wall is created can be reversed so that it can be readily dismantled and/or modified without having to apply destructive force. Thus one does not have to destroy the wall to take it down or, destroy it in part and then rebuild it, to enable disassembly to or modification of the building. As will be appreciated, the wall can be created by simply bolting the posts 6 , 9 in place and then slotting the panels in place, one after the other, without screws or bolts for the panels. Because the panels butt tightly into and against the posts the rubber seals between the posts and panels ensure a watertight fit.
[0047] Those skilled in the art will appreciate that to enable disassembly of the wall at least one of the posts will have a profile slightly different to the others. As shown at FIGS. 14 and 15 , most or the medial posts generally have an “H” profile. The post (not shown) which enables disassembly is similar except that it has one the “H” tails 27 missing to give a generally “h” profile. The missing tail means that one of the panels can be swung outwards from the post inside the building to enable access to the bolts which proceed through the tongues 16 and 17 of that post. From there the wall can be disassembled panel after post. A capping (not shown) may be removably screwed in place over the area of the “missing tail” for aesthetic purposes when the wall is in its fully assembled state.
[0048] In some embodiments of the invention the panels 9 may have only a glass pane or panes, ie without a non-transparent sheet or sheets. In that case the panels may thus be windows only and in that event, and for the purposes of this document, the arrangement should still be regarded as a wall or part thereof.
[0049] While some preferred forms of the invention have been described by way of example it should be appreciated that modifications and improvements can occur without departing from the scope of the following claims. | A method of constructing an external weatherpoof wall of a building 1 by way of a series of posts 6, 10 and panels 9 . The method involves orienting a post 6, 10 vertically between the roof and wall and securing it in place. A panel is then oriented vertically and moved against the post. A further post is placed against the free side of the panel and the procedure repeated until a wall is established panel after post. The wall can be disassembled without the application of destructive force. Preferably only the posts are bolted to the roof and floor and the panels are held between the posts without receiving fixing means such as screws, bolts, or the like to hold them there. | 4 |
CROSS-REFERENCE TO RELATED PATENT APPLICATION AND CLAIM OF PRIORITY
[0001] This application claims priority from Korean Patent Application No. 10-2006-0096124, filed on Sep. 29, 2006, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a cyclopentaphenanthrene-based compound and an organoelectroluminescent device employing the same. More particularly, the present invention relates to a cyclopentaphenanthrene-based compound and an organoelectroluminescent device including an organic layer formed of the cyclopentaphenanthrene-based compound.
[0004] 2. Description of the Related Art
[0005] Organoelectroluminescent devices are active emission display devices that emit light by recombination of electrons and holes in a thin layer (hereinafter, referred to as “organic layer”) formed of a fluorescent or phosphorescent organic compound when a current is supplied to the organic layer. The organoelectroluminescent devices have advantages such as lightness, simple constitutional elements, an easy fabrication process, superior image quality, and a wide viewing angle. In addition, the organoelectroluminescent devices can perfectly create dynamic images, achieve high color purity, and have electrical properties suitable for portable electronic equipment due to low power consumption and low driving voltage.
[0006] Eastman Kodak Co. has developed an organoelectroluminescent device with a multi-layered structure including an aluminum quinolinol complex layer and a triphenylamine derivative layer (U.S. Pat. No. 4,885,211), and an organoelectroluminescent device including an organic light-emitting layer formed of a low molecular weight material capable of emitting light in a broad wavelength range from UV to infrared light (U.S. Pat. No. 5,151,629).
[0007] Light-emitting devices are self-emitting devices and have advantages such as a wide viewing angle, good contrast, and a rapid response time. Light-emitting devices can be classified into inorganic light-emitting devices using an emitting layer formed of an inorganic compound and organic light-emitting devices (OLEDs) using an emitting layer formed of an organic compound. OLEDs show better brightness, driving voltage, and response speed characteristics and can create polychromatic light, compared to inorganic light-emitting devices, and thus, extensive research into OLEDs has been conducted.
[0008] Generally, OLEDs have a stacked structure including an anode, an organic light-emitting layer, and a cathode. OLEDs may also have various structures such as anode/hole injection layer/hole transport layer/emitting layer/electron transport layer/electron injection layer/cathode or anode/hole injection layer/hole transport layer/emitting layer/hole blocking layer/electron transport layer/electron injection layer/cathode.
[0009] Materials used for OLEDs can be classified into vacuum-depositable materials and solution-coatable materials according to an organic layer formation process. Vacuum-depositable materials must have a vapor pressure of 10 −6 torr or more at 500° C. or less, and may be low molecular weight materials having a molecular weight of 1,200 or less. Solution-coatable materials must have solubility sufficient to form solutions, and include mainly an aromatic or heterocyclic ring.
[0010] When manufacturing organoelectroluminescent devices using a vacuum deposition process, manufacturing costs may increase due to use of a vacuum system, and it may be difficult to manufacture high-resolution pixels for natural color displays using a shadow mask. On the other hand, when manufacturing organoelectroluminescent devices using a solution coating process, e.g., inkjet printing, screen printing, or spin coating, the manufacturing process is simple, manufacturing costs are low, and a relatively high resolution can be achieved compared to when using a shadow mask.
[0011] However, when using solution-coatable materials, the performance (e.g., thermal stability, color purity) of light-emitting molecules is lowered compared to when using vacuum-depositable materials. Even though the light-emitting molecules of the solution-coatable materials have good performance, there arise problems that the materials, when formed into an organic layer, are gradually crystallized to grow into a size corresponding to a visible light wavelength range, and thus, the grown crystals scatter visible light, thereby causing a turbidity phenomenon, and pinholes, etc. may be formed in the organic layer, thereby causing device degradation.
[0012] Japanese Patent Laid-Open Publication No. 1999-003782 discloses a two naphthyl-substituted anthracene compound that can be used in an emitting layer or a hole injection layer. However, the anthracene compound is poorly soluble in a solvent, and further, an organoelectroluminescent device using the anthracene compound has unsatisfactory characteristics.
[0013] Therefore, it still needs to develop organoelectroluminescent devices having reduced driving voltage and improved brightness, efficiency, and color purity characteristics by virtue of blue light-emitting compounds which have good thermal stability and can form good organic layers.
[0014] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
SUMMARY OF THE INVENTION
[0015] The present invention provides a cyclopentaphenanthrene-based compound which is adapted for both dry and wet processes, and has excellent thermal stability and good charge transport and emission characteristics, and an organoelectroluminescent device employing the same.
[0016] According to an aspect of the present invention, there is provided a cyclopentaphenanthrene-based compound represented by Formula 1 below:
[0000]
[0017] wherein each Q is independently a substituted or unsubstituted C6-C30 arylene group or a substituted or unsubstituted C2-C30 heteroarylene group;
[0018] each Y is independently a substituted or unsubstituted C2-C30 alkylene group, a substituted or unsubstituted C6-C30 cycloalkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C2-C30 heteroarylene group, or a substituted or unsubstituted C2-C30 alkenylene group;
[0019] X is hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group;
[0020] m is an integer of 0 to 3, and when m is 2 or 3, Qs are the same or different from each other;
[0021] n is an integer of 0 to 3, and when n is 2 or 3, Ys are the same or different from each other;
[0022] R 1 and R 2 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group, and R 1 and R 2 can be optionally linked together to form a substituted or unsubstituted C3-C20 aliphatic ring, a substituted or unsubstituted C5-C30 heteroaliphatic ring, a substituted or unsubstituted C6-C30 aromatic ring, or a substituted or unsubstituted C2-C30 heteroaromatic ring; and;
[0023] R 3 through R 16 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0024] R 19 is hydrogen, halogen, a cyano group, a hydroxyl group, or a substituted or unsubstituted C1-C20 alkyl group.
[0025] In one embodiment of the present invention, the
[0000]
[0000] in Formula 1 may be linked together to form one of rings represented by Formulae 2 through 5 below:
[0000]
[0026] wherein each R 17 is independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C 2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0027] A is a single bond, O, S, Se, or (CH 2 ) p where p is an integer of 1 to 5.
[0028] According to an embodiment of the present invention, the compound of Formula 1 above may be selected from compounds represented by Formulae 6 through 8 below:
[0000]
[0029] wherein each Y is independently a substituted or unsubstituted C2˜C30 alkylene group, a substituted or unsubstituted C6˜C30 cycloalkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C2-C30 heteroarylene group, or a substituted or unsubstituted C2-C30 alkenylene group;
[0030] each Q is independently a substituted or unsubstituted C6-C30 arylene group or a substituted or unsubstituted C2-C30 heteroarylene group;
[0031] m is an integer of 0 to 3, and when m is 2 or 3, Qs are the same or different from each other;
[0032] n is an integer of 0 to 3, and when n is 2 or 3, Ys are the same or different from each other;
[0033] X is hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group;
[0034] R 9 through R 16 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group;
[0035] R 1 ′ and R 2 ′ are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0036] each R 18 is independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group.
[0037] According to another aspect of the present invention, there is provided an organoelectroluminescent device including: a first electrode; a second electrode; and at least one organic layer interposed between the first electrode and the second electrode, the organic layer including the above-described organoelectroluminescent compound.
[0038] In the embodiments of the present invention, a low molecular weight compound obtained by reacting a cyclopentaphenanthrene compound wherein the 2- or 6-position is functionalized with halogen, borate, aldehyde, hydroxyl, or the like, with another compound, is used as an organoelectroluminescent material. Various substituents can be incorporated into the 4-position of the cyclopentaphenanthrene of the low molecular weight compound, thereby enabling more stable film formation and improving solubility in a solvent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
[0040] FIGS. 1A through 1C are schematic views illustrating organoelectroluminescent devices according to embodiments of the present invention; and
[0041] FIG. 2 is a graph illustrating emission characteristics of an organoelectroluminescent device according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0042] Embodiments of the present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.
[0043] An embodiment of the present invention provides a cyclopentaphenanthrene-based compound represented by Formula 1 below:
[0000]
[0044] wherein each Q is independently a substituted or unsubstituted C6-C30 arylene group or a substituted or unsubstituted C2-C30 heteroarylene group;
[0045] each Y is independently a substituted or unsubstituted C2-C30 alkylene group, a substituted or unsubstituted C6-C30 cycloalkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C2-C30 heteroarylene group, or a substituted or unsubstituted C2-C30 alkenylene group;
[0046] X is hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1˜C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group;
[0047] m is an integer of 0 to 3, and when m is an integer of 2 or 3, Qs may be the same or different from each other;
[0048] n is an integer of 0 to 3, and when n is an integer of 2 or 3, Ys may be the same or different from each other;
[0049] R 1 and R 2 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group, and R 1 and R 2 can be optionally linked together to form a substituted or unsubstituted C3-C20 aliphatic ring, a substituted or unsubstituted C5-C30 heteroaliphatic ring, a substituted or unsubstituted C6-C30 aromatic ring, or a substituted or unsubstituted C2-C30 heteroaromatic ring;
[0050] R 3 through R 16 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0051] R 19 is hydrogen, halogen, a cyano group, a hydroxyl group, or a substituted or unsubstituted C1-C20 alkyl group.
[0052] In the present application, when two or more are independently selected, it means that two or more may be the same or different from each other.
[0053] According to an embodiment of the present invention, in Formula 1, m may be an integer of 1 to 3, and n may be an integer of 1 to 3.
[0054] According to an embodiment of the present invention, in Formula 1, the
[0000]
[0000] when linked together, may form rings represented by Formulae 2 through 5 below:
[0000]
[0055] wherein each R 17 is independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C 2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0056] A is a single bond, O, S, Se, or (CH 2 ) p where p is an integer of 1 to 5.
[0057] The compound of Formula 1 according to the embodiment of the present invention may be selected from compounds represented by Formulae 6 through 8 below:
[0000]
[0058] wherein each Q is independently a substituted or unsubstituted C6-C30 arylene group or a substituted or unsubstituted C2-C30 heteroarylene group;
[0059] each Y is independently a substituted or unsubstituted C2˜C30 alkylene group, a substituted or unsubstituted C6˜C30 cycloalkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C2-C30 heteroarylene group, or a substituted or unsubstituted C2-C30 alkenylene group;
[0060] X is hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group;
[0061] m is an integer of 0 to 3, and when m is 2 or 3, Qs are the same or different from each other;
[0062] n is an integer of 0 to 3, and when n is 2 or 3, Ys are the same or different from each other;
[0063] R 1 ′ and R 2 ′ are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group, and R 1 ′ and R 2 ′ can be optionally linked together to form a substituted or unsubstituted C3-C20 aliphatic ring, a substituted or unsubstituted C5-C30 heteroaliphatic ring, a substituted or unsubstituted C6-C30 aromatic ring, or a substituted or unsubstituted C2-C30 heteroaromatic ring;
[0064] R 9 through R 16 are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group; and
[0065] each R 18 is independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aralkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group.
[0066] In an embodiment of the present invention, m may be an integer of 1 to 3, and n may be an integer of 1 to 3.
[0067] In an embodiment of the present invention, -[Q] m - may be selected from the group consisting of chemical structures represented by Formulae 9 through 9R below, but is not limited to:
[0000]
[0068] In Formulae 6 through 8, —[Y] n —X may be selected from the group consisting of chemical structures represented by Formulae 10A to 10R, 11A to 11S, 12A to 12Q, 13A to 13LL, 14A to 14R, and 15A to 15Z below, but is not limited to:
[0000]
[0069] In Formulae 9A through 15Z, R′ and R″ are each independently hydrogen, halogen, a cyano group, a hydroxyl group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C30 heteroaryl group, —N(Z 1 )(Z 2 ) or —Si(Z 3 )(Z 4 )(Z 5 ) where Z 1 , Z 2 , Z 3 , Z 4 , and Z 5 are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, a substituted or unsubstituted C5-C20 cycloalkyl group, or a substituted or unsubstituted C5-C30 heterocycloalkyl group.
[0070] In the above formulae, the “aryl group” refers to a monovalent group having an aromatic ring system and may contain two or more ring systems. The two or more ring systems may be attached or fused to each other. The “heteroaryl group” refers to an aryl group in which at least one carbon atom is substituted by at least one selected from the group consisting of N, O, S, and P.
[0071] The “cycloalkyl group” refers to an alkyl group having a ring system, and the “heterocycloalkyl group” refers to a cycloalkyl group in which at least one carbon atom is substituted by at least one selected from the group consisting of N, O, S, and P.
[0072] In the above formulae, the alkyl group, the alkoxy group, the aryl group, the heteroaryl group, the cycloalkyl group, and the heterocycloalkyl group may be substituted by at least one substituent selected from the group consisting of —F; —Cl; —Br; —CN; —NO 2 ; —OH; a C1-C20 alkyl group which is unsubstituted or substituted by —F, —Cl, —Br, —CN, —NO 2 , or —OH; a C1-C20 alkoxy group which is unsubstituted or substituted by —F, —Cl, —Br, —CN, —NO 2 , or —OH; a C6-C30 aryl group which is unsubstituted or substituted by a C1-C20 alkyl group, a C1-C20 alkoxy group, —F, —Cl, —Br, —CN, —NO 2 , or —OH; a C2-C30 heteroaryl group which is unsubstituted or substituted by a C1-C20 alkyl group, a C1-C20 alkoxy group, —F, —Cl, —Br, —CN, —NO 2 , or —OH; a C5-C20 cycloalkyl group which is unsubstituted or substituted by a C1-C20 alkyl group, a C1-C20 alkoxy group, —F, —Cl, —Br, —CN, —NO 2 , or —OH; a C5-C30 heterocycloalkyl group which is unsubstituted or substituted by a C1-C20 alkyl group, a C1-C20 alkoxy group, —F, —Cl, —Br, —CN, —NO 2 , or —OH; and a group represented by —N(G 6 )(G 7 ), where, G 6 and G 7 are each independently hydrogen; a C1-C10 alkyl group; or a C6-C30 aryl group which is substituted by a C1-C10 alkyl group.
[0073] In more detail, R 1 through R 18 are each independently selected from the group consisting of a hydrogen, a halogen, a cyano group, a hydroxyl group, a C1-C10 alkyl group, a C1-C10 alkoxy group, and a substituted or unsubstituted group as follows: a phenyl group, a biphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, a biphenylenyl, an anthracenyl group, an azulenyl group, a heptalenyl group, an acenaphthylenyl group, a phenalenyl group, a fluorenyl group, a methylanthryl group, a phenanthrenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, an ethyl-chrysenyl group, a picenyl group, a perylenyl group, a chloroperylenyl group, a pentaphenyl group, a pentacenyl group, a tetraphenylenyl group, a hexaphenyl group, a hexacenyl group, a rubicenyl group, a coronenyl group, a trinaphthylenyl group, a heptaphenyl group, a heptacenyl group, a pyranthrenyl group, an ovalenyl group, a carbazolyl group, a thiophenyl group, an indolyl group, a purinyl group, a benzimidazolyl group, a quinolinyl group, a benzothiophenyl group, a parathiazinyl group, a pyrrolyl group, a pyrazolyl group, an imidazolyl group, an imidazolinyl group, an oxazolyl group, a thiazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a pyridinyl group, a pyridazinyl group, a pyrimidinyl group, a pyrazinyl group, a thianthrenyl group, a cyclopentyl group, a cyclohexyl group, an oxiranyl group, a pyrrolidinyl group, a pyrazolidinyl group, an imidazolidinyl group, a piperidinyl group, a piperazinyl group, a morpholinyl group, a di(C6-C30 aryl)amino group, a tri(C6-C30 aryl)silyl group, and derivatives thereof.
[0074] As used herein, the term “derivative(s)” refers to the above-illustrated group(s) wherein at least one hydrogen is substituted by a substituent as described above.
[0075] The compound according to the embodiment of the present invention may be selected from the group consisting of compounds represented by Formulae 16 through 72 below, but is not limited to:
[0000]
[0076] The compound of Formula 1 according to the embodiment of the present invention can be synthesized using a common synthesis method. For a detailed synthesis procedure of the compound according to the embodiment of the present invention, reference will be made to the reaction schemes in the following synthesis examples.
[0077] The present invention also provides an organoelectroluminescent device including a first electrode, a second electrode, and an organic layer interposed between the first electrode and the second electrode, the organic layer including at least one compound represented by Formula 1 above.
[0078] The compound of Formula 1 is suitable for an organic layer of an organoelectroluminescent device, in particular an emitting layer, a hole injection layer, or a hole transport layer.
[0079] The organoelectroluminescent device according to an embodiment of the present invention includes a compound which has good solubility and thermal stability and can form a stable organic layer, and thus, can show a good driving voltage and enhanced emission characteristics (e.g., color purity), unlike a conventional organoelectroluminescent device including a less stable organic layer when manufactured using a solution coating process.
[0080] The organoelectroluminescent device according to the embodiment of the present invention can be variously structured. That is, the organoelectroluminescent device may further include at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer, between the first electrode and the second electrode.
[0081] In more detail, organoelectroluminescent devices according to embodiments of the present invention are illustrated in FIGS. 1A , 1 B, and 1 C. Referring to FIG. 1A , an organoelectroluminescent device has a stacked structure of first electrode/hole injection layer/hole transport layer/emitting layer/electron transport layer/electron injection layer/second electrode. Referring to FIG. 1B , an organoelectroluminescent device has a stacked structure of first electrode/hole injection layer/emitting layer/electron transport layer/electron injection layer/second electrode. Referring to FIG. 1C , an organoelectroluminescent device has a stacked structure of first electrode/hole injection layer/hole transport layer/emitting layer/hole blocking layer/electron transport layer/electron injection layer/second electrode. Here, at least one of the emitting layer, the hole injection layer, and the hole transport layer may include a compound according to an embodiment of the present invention.
[0082] An emitting layer of the organoelectroluminescent device according to the embodiments of the present invention may include a red, green, blue, or white phosphorescent or fluorescent dopant. The phosphorescent dopant may be an organometallic compound including at least one element selected from the group consisting of Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, and Tm.
[0083] Hereinafter, an exemplary method of manufacturing an organoelectroluminescent device according to an embodiment of the present invention will be described with reference to FIG. 1C .
[0084] First, a first electrode is formed on a substrate by a deposition or sputtering process using a first electrode material with a high work function. The first electrode may be an anode. Here, the substrate may be a substrate commonly used in organoelectroluminescent devices. Preferably, the substrate may be a glass or transparent plastic substrate which is excellent in mechanical strength, thermal stability, transparency, surface smoothness, handling property, and water repellency. The first electrode material may be a material with transparency and good conductivity, e.g., indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO 2 ), or zinc oxide (ZnO).
[0085] Next, a hole injection layer (HIL) may be formed on the first electrode using various methods such as vacuum deposition, spin-coating, casting, or Langmuir-Blodgett (LB) method.
[0086] In the case of forming the hole injection layer using a vacuum deposition process, the deposition conditions vary according to the type of a hole injection layer material, the structure and thermal characteristics of the hole injection layer, etc. However, it is preferred that the hole injection layer should be deposited to a thickness of 10 Å to 5 μm at a deposition rate of 0.01 to 100 Å/sec, at a temperature of 100 to 500° C., in a vacuum level of 10 −8 to 10 −3 torr.
[0087] In the case of forming the hole injection layer using a spin-coating process, the coating conditions vary according to the type of a hole injection layer material, the structure and thermal characteristics of the hole injection layer, etc. However, it is preferred that the spin-coating should be performed at a coating speed of about 2,000 to 5,000 rpm, and, after the spin-coating, a thermal treatment should be performed at a temperature of about 80 to 200° C. for the purpose of solvent removal.
[0088] The hole injection layer material may be a compound of Formula 1 as described above. In addition, the hole injection layer material may be a known hole injection material, e.g., a phthalocyanine compound (e.g., copper phthalocyanine) disclosed in U.S. Pat. No. 4,356,429 which is incorporated herein by reference, a Starburst-type amine derivative (e.g., TCTA, m-MTDATA, or m-MTDAPB) disclosed in Advanced Material, 6, p. 677 (1994) which is incorporated herein by reference, or a soluble conductive polymer, e.g., polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (Pani/CSA), or polyaniline/poly(4-styrenesulfonate) (PANI/PSS).
[0000]
[0089] The hole injection layer may be formed to a thickness of about 100 to 10,000 Å, preferably 100 to 1,000 Å. If the thickness of the hole injection layer is less than 100 Å, hole injection characteristics may be lowered. On the other hand, if the thickness of the hole injection layer exceeds 10,000 Å, a driving voltage may be increased.
[0090] Next, a hole transport layer (HTL) may be formed on the hole injection layer using various methods such as vacuum deposition, spin-coating, casting, or LB method. In the case of forming the hole transport layer using vacuum deposition or spin-coating, the deposition or coating conditions vary according to the type of a used compound, but are generally almost the same as those for the formation of the hole injection layer.
[0091] A hole transport layer material may be a compound of Formula 1 as described above. In addition, the hole transport layer material can be a known hole transport material, e.g., a carbazole derivative such as N-phenylcarbazole or polyvinylcarbazole; an amine derivative having an aromatic fused ring such as N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine (TPD) or N,N′-di(naphthalene-1-yl)-N,N′-diphenylbenzidine (α-NPD), etc.
[0092] The hole transport layer may be formed to a thickness of about 50 to 1,000 Å, preferably 100 to 600 Å. If the thickness of the hole transport layer is less than 50 Å, hole transport characteristics may be lowered. On the other hand, if the thickness of the hole transport layer exceeds 1,000 Å, a driving voltage may be increased.
[0093] Next, an emitting layer (EML) may be formed on the hole transport layer using vacuum deposition, spin-coating, casting, or LB method. In the case of forming the emitting layer using vacuum deposition or spin-coating, the deposition or coating conditions vary according to the type of a used compound, but are generally almost the same as those for the formation of the hole injection layer.
[0094] The emitting layer may include a compound of Formula 1 as described above. Here, a known fluorescent host material suitable for the compound of Formula 1 or a known dopant material may be used together with the compound of Formula 1. The compound of Formula 1 may be used as a phosphorescent host alone or in combination with 4,4′-N,N′-dicarbazole-biphenyl (CBP), poly(n-vinylcarbazole) (PVK), etc. As a phosphorescent dopant, there may be used a red phosphorescent dopant (e.g., PtOEP, RD 61 (UDC)), a green phosphorescent dopant (e.g., Ir(PPy) 3 (PPy=2-phenylpyridine)), or a blue phosphorescent dopant (e.g., F 2 Irpic).
[0095] When the compound of Formula 1 is used as a dopant, the doping concentration of the dopant is not particularly limited. Generally, the content of the dopant is 0.01 to 15 parts by weight based on 100 parts by weight of a host. When the compound of Formula 1 is used as a single host, the doping concentration of a dopant is not particularly limited. Generally, the content of a dopant is 0.01 to 15 parts by weight based on 100 parts by weight of the host. When the compound of Formula 1 is used as a host in combination with another host, the content of the compound of Formula 1 is 30-99 parts by weight based on the total weight (100 parts by weight) of the hosts.
[0096] The emitting layer may be formed to a thickness of about 100 to 1,000 Å, preferably 200 to 600 Å. If the thickness of the emitting layer is less than 100 Å, emission characteristics may be lowered. On the other hand, if the thickness of the emitting layer exceeds 1,000 Å, a driving voltage may be increased.
[0097] In a case where the emitting layer includes a phosphorescent dopant, a hole blocking layer (HBL) may be formed on the emitting layer using vacuum deposition, spin-coating, casting, or LB method, in order to prevent the diffusion of triplet excitons or holes into an electron transport layer. In the case of forming the hole blocking layer using vacuum deposition or spin coating, the deposition or coating conditions vary according to the type of a used compound, but are generally almost the same as those for the formation of the hole injection layer. An available hole blocking material may be an oxadiazole derivative, a triazole derivative, a phenanthroline derivative, BCP, an aluminum complex, etc.
[0000]
[0098] The hole blocking layer may be formed to a thickness of about 50 to 1,000 Å, preferably 100 to 300 Å. If the thickness of the hole blocking layer is less than 50 Å, hole blocking characteristics may be lowered. On the other hand, if the thickness of the hole blocking layer exceeds 1,000 Å, a driving voltage may be increased.
[0099] Next, an electron transport layer (ETL) may be formed using various methods such as vacuum deposition, spin-coating, or casting. In the case of forming the electron transport layer using vacuum deposition or spin-coating, the deposition or coating conditions vary according to the type of a used compound, but are generally almost the same as those for the formation of the hole injection layer. An electron transport layer material serves to stably transport electrons from an electron donor electrode (a cathode) and may be a known material such as an oxazole-based compound, an isoxazole-based compound, a triazole-based compound, an isothiazole-based compound, an oxadiazole-based compound, a thiadiazole-based compound, a perylene-based compound, an aluminum complex (e.g.: Alq3 (tris(8-quinolinolato)-aluminum) BAlq, SAlq, or Almq3), a gallium complex (e.g.: Gaq′2OPiv, Gaq′2OAc, 2(Gaq′2)), etc.
[0000]
[0100] The electron transport layer may be formed to a thickness of about 100 to 1,000 Å, preferably 200 to 500 Å. If the thickness of the electron transport layer is less than 100 Å, electron transport characteristics may be lowered. On the other hand, if the thickness of the electron transport layer exceeds 1,000 Å, a driving voltage may be increased.
[0101] An electron injection layer (EIL) may be formed on the electron transport layer in order to facilitate the injection of electrons from a cathode into the emitting layer. An electron injection layer material is not particularly limited.
[0102] The electron injection layer material may be selected from known materials such as LiF, NaCl, CsF, Li 2 O, or BaO. The deposition conditions of the electron injection layer vary according to the type of a used compound, but are generally almost the same as those for the formation of the hole injection layer.
[0103] The electron injection layer may be formed to a thickness of about 1 to 100 Å, preferably 5 to 50 Å. If the thickness of the electron injection layer is less than 1 Å, electron injection characteristics may be lowered. On the other hand, if the thickness of the electron injection layer exceeds 100 Å, a driving voltage may be increased.
[0104] Finally, a second electrode may be formed on the electron injection layer using vacuum deposition or sputtering. The second electrode may be used as a cathode. A material for forming the second electrode may be metal or alloy with a low work function, an electroconductive compound, or a mixture thereof. For example, the second electrode material may be lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), etc. The second electrode may also be a transmissive cathode formed of ITO or IZO to provide a front-emission type device.
[0105] Hereinafter, the present invention will be described more specifically with reference to the following working examples. However, the following working examples are only for illustrative purposes and are not intended to limit the scope of the invention.
EXAMPLES
[0106]
Synthesis Example 1
1) Synthesis of 8,9-dihydro-4H-cyclopenta[def]phenanthrene
[0107] 4H-cyclopenta[def]phenanthrene (4.75 g, 25 mmol) was put into a Par reactor bottle, and EtOH (200 ml) was added thereto. 5% Pd/C (3.99 g) was added to the reaction solution, and the resultant solution was incubated under a hydrogen pressure of 40 psi for 24 hours. After the reaction was terminated, the reaction solution was filtered, and the filtrate was concentrated under a reduced pressure to give a white product (4.32 g, 90%).
2) Synthesis of 2-bromo-8,9-dihydro-4H-cyclopenta[def]phenanthrene
[0108] 8,9-dihydro-4H-cyclopenta[def]phenanthrene (4.0 g, 20.8 mmol) was put into a 250 ml round bottom flask (RBF), and CCl 4 (100 ml) was added thereto. The reaction mixture was cooled to 0° C., and Br 2 (3.3 g, 20.8 mmol) was dropwise added thereto. The reaction solution was incubated for 4 hours and a 10% NaSO 3 solution was added thereto. The organic phase was separated, concentrated under a reduced pressure, and recrystallized from n-hexane to obtain 4.7 g of a 2-bromo-8,9-dihydro-4H-cyclopenta[def]phenanthrene compound.
3) Synthesis of Compound 1
[0109] 2-bromo-8,9-dihydro-4H-cyclopenta[def]phenanthrene (4.45 g, 16.4 mmol) in a 250 ml round bottom flask was dissolved with xylene, and o-chloranil (4.3 g) was added thereto at room temperature. The reaction mixture was heated and refluxed in an oil bath for 72 hours. After the reaction was terminated, the reaction solution was cooled and concentrated under a reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: n-hexane) to give a compound 1 (3.5 g, 79%).
[0110] 1 H NMR (300 MHz, CDCl 3 , δ): 7.98 (2H, s), 7.79 (2H, s), 7.73 (2H, s), 6.94 (dd, 1H), 4.28 (2H, s)
4) Synthesis of Compound 2
[0111] 2-bromo-4H-cyclopenta[def]phenanthrene (2.6 g, 9.7 mmol) and octyl bromide (3.6 g, 18.5 mmol) in a 50 ml round bottom flask were dissolved with toluene (10 ml), and TBAB (tetrabutylammoniumbromide) (0.125 g, 0.385 mmol) was added thereto. A solution of NaOH (3.1 g, 77 mmol) in water (50 ml) was added to the reaction mixture, and the resultant solution was refluxed for two days. After the reaction was terminated, the reaction solution was extracted with chloroform. The organic phase was dried over MgSO 4 , concentrated, and purified by silica gel column chromatography (eluent: n-hexane). The eluate was distilled under a reduced pressure to remove unreacted octyl bromide, thereby giving a compound 2 (3.6 g, 75%).
[0112] 1 H NMR (300 MHz, CDCl 3 , δ): 7.98 (2H, s), 7.79 (2H, s), 7.73 (2H, s), 6.94 (dd, 1H), 1.93 (m, 4H), 1.21 (m, 20H), 0.87 (m, 6H), 0.65 (broad s, 4H)
Synthesis Example 2
1) Synthesis of 2-bromo-cyclopenta[def]phenanthren-4-one
[0113] Benzene (200 ml) was put into a 250 ml round bottom flask, and the compound 1 (3.6 g, 13.3 mmol) was added thereto. MnO 2 (150 g) was added to the reaction mixture, and the resultant mixture was heated and refluxed in an oil bath for 18 hours. After the reaction was terminated, the reaction solution was filtered to remove MnO 2 , and sufficiently washed with CHCl 3 , THF, and MeOH in sequence. The filtrate was concentrated under a reduced pressure and the residue was recrystallized from acetone to give the titled compound (1.5 g, 39%).
2) Synthesis of Intermediate A
[0114] 2-bromo-cyclopenta[def]phenanthrene-4-one (1.0 g, 2.76 mmol) was dissolved in dry ether (30 ml) and THF (10 ml), and phenylmagnesiumbromide (3.0M in ether) was gradually added thereto under a nitrogen gas atmosphere. The reaction mixture was refluxed for three hours, and water was added thereto so that the reaction was terminated. The resultant solution was adjusted to pH of 3-4 with a 1N—HCl solution and extracted with ethyl ether. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated under a reduced pressure. The resultant solid was purified by silica gel column chromatography to give an intermediate A as a solid phase (0.79 g, 65%).
3) Synthesis of Compound 3
[0115] The intermediate A (0.79 g, 1.79 mmol) was dissolved in dry benzene (20 ml), and trifluoromethanesulfonic acid (0.48 ml, 5.38 mmol, 3 eq.) was dropwise added thereto. The reaction mixture was incubated at 80° C. for two hours. The resultant solution was diluted with water and extracted with ethyl acetate. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated under a reduced pressure. The resultant solid was purified by silica gel column chromatography and recrystallized from a EtOAc-Hex mixed solvent to give a compound 3 as a solid phase (0.65 g, 63%). 1 H NMR (300 MHz, CDCl3, δ): 7.22-7.26 (m, 10H), 7.70 (s, 2H), 7.80 (s, 3H), 8.00 (s, 2H)
Synthesis Example 3
1) Synthesis of Intermediate B
[0116] 2-bromo-cyclopenta[def]phenanthrene-4-one (0.95 g, 3.35 mmol) and phenol (30 ml) were put into a 250 ml 3-neck round bottom flask. The reaction mixture was heated and incubated for five hours while a HCl gas was run into the mixture. After the reaction was terminated, the reaction solution was concentrated under a reduced pressure to remove unreacted phenol. The residue was purified by silica gel column chromatography to give an intermediate B (0.95 g, 62.5%).
2) Synthesis of Compound 4
[0117] The intermediate B (0.95 g, 2.1 mmol) was put into a 100 ml round bottom flask, and DMF (5 ml) and acetonitrile (20 ml) were added thereto. K 2 CO 3 (1.52 g) and octyl bromide (2.11 g) were sequentially added, and the reaction mixture was heated and refluxed for 18 hours. After the reaction was terminated, the organic phase was separated and purified by silica gel column chromatography to give a compound 4 (0.70 g, 49%). 1 H NMR (300 MHz, CDCl 3 , δ): 7.78 (2H, d), 7.79 (2H, s), 7.67 (2H, d), 7.64 (1H, d), 7.11 (4H, dd), 6.76 (4H, dd), 3.89 (4H, t), 1.74 (4H, q), 1.28 (20H, m), 0.88 (6H, m).
Synthesis Example 4
1) Synthesis of Intermediate C
[0118] 2-bromobiphenyl (0.68 g, 2.95 mmol) was dissolved in anhydrous THF (10 ml), and the reaction mixture was cooled to −78° C. Then, t-BuLi (3.5 ml) was gradually dropwise added. The reaction mixture was stirred for one hour, and a solution of 2-bromo-cyclopenta[def]phenanthrene-4-one (1 g, 3.53 mmol) in anhydrous THF (5 ml) was dropwise added thereto for 30 minutes. After the reaction was terminated, the reaction solution was concentrated under a reduced pressure and extracted with ethylacetate and brine to separate an organic phase. The organic phase was concentrated and the residue was purified by silica gel column chromatography to give an intermediate C (1.2 g).
2) Synthesis of Compound 5
[0119] The intermediate C was dissolved in acetic acid (30 ml), and the reaction mixture was cooled to 0° C. Then, a concentrated HCl (1 ml) was dropwise added, and the reaction mixture was incubated for two hours. After the reaction was terminated, the reaction solution was filtered and washed with acetic acid and methanol to give a white solid (1.05 g, 91%). 1 H NMR (300 MHz, CDCl3, δ): 7.22-7.26 (m, 8H), 7.70 (s, 2H), 7.80 (s, 2H), 8.00 (s, 2H)
Synthesis of Emitting Materials
1) Synthesis of Material 1 (Formula 18)
[0120] The compound 2 (1.0 g, 1 eq., 2.02 mmol), 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane (0.77 g, 1 eq., 2.02 mmol), tetrakis(triphenylphosphine)palladium(0) (0.23 g, 0.1 eq., 0.2 mmol), 2M K 2 CO 3 (1 ml, 1 eq., 2.02 mmol), and tetrabutylammoniumbromide (0.65 g, 1 eq., 2.02 mmol) were put into a 100 ml round bottom flask under an argon gas atmosphere, and THF (50 ml) and toluene (20 ml) were added thereto. The reaction mixture was refluxed at 100° C. for 16 hours. When the reaction solution turned dark brown, water was added, and the resultant solution was extracted with ethylacetate. The extracted organic phase was dried over anhydrous magnesium sulfate and filtered to remove a solvent. The residue was dissolved in a trace amount of toluene and purified on a silica gel column. The resultant solid was recrystallized from toluene and methanol to give a material 1 represented by Formula 18 (0.71 g, 52%). 1 H NMR (300 MHz, CDCl 3 , δ): 8.11 (s, 2H), 7.98 (s, 3H), 7.81 (s, 2H), 7.75-7.10 (m, 13H), 1.93 (m, 4H), 1.21 (m, 20H), 0.87 (m, 6H), 0.65 (broad s, 4H).
2) Synthesis of Material 2 (Formula 19)
[0121] A material 2 represented by Formula 19 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 2-anthracene-9-yl-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.15 (s, 2H), 7.95 (s, 3H), 7.78 (s, 2H), 7.75-7.16 (m, 19H),
3) Synthesis of Material 3 (Formula 20)
[0122] A material 3 represented by Formula 20 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2. 1 H NMR (300 MHz, CDCl 3 , δ): 8.13 (s, 2H), 7.92 (s, 3H), 7.80 (s, 2H), 7.73-7.08 (m, 23H)
4) Synthesis of Material 4 (Formula 21)
[0123] A material 4 represented by Formula 21 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-(10-naphthalene-2-yl-anthracene-9-yl)-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.11 (s, 2H), 7.96 (s, 3H), 7.81 (s, 2H), 7.79-7.10 (m, 25H)
5) Synthesis of Material 5 (Formula 23)
[0124] A material 5 represented by Formula 23 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-[10-(4-naphthalene-1-yl-phenyl)-anthracene-9-yl]-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.17 (s, 2H), 7.90 (s, 3H), 7.78 (s, 2H), 7.75-7.01 (m, 29H)
6) Synthesis of Material 6 (Formula 26)
[0125] A material 6 represented by Formula 26 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-(10-[1,1′,3′,1″]tetraphenyl-5′-yl-anthracene-9-yl)-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.02 (s, 2H), 7.98 (s, 3H), 7.92 (s, 2H), 7.87-6.95 (m, 31H)
7) Synthesis of Material 7 (Formula 33)
[0126] A material 7 represented by Formula 33 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-(3-methyl-10-naphthalene-1-yl-anthracene-9-yl)-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.09 (s, 2H), 7.88 (s, 3H), 7.83 (s, 2H), 7.69-7.12 (m, 24H), 2.46 (s, 3H)
8) Synthesis of Material 8 (Formula 38)
[0127] A material 8 represented by Formula 38 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-[10-(3-naphthalene-2-yl-phenyl)-anthracene-9-yl]-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.18 (s, 2H), 7.96 (s, 3H), 7.85 (s, 2H), 7.74-7.02 (m, 29H)
9) Synthesis of Material 9 (Formula 40)
[0128] A material 9 represented by Formula 40 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 4 was used instead of the compound 2. 1 H NMR (300 MHz, CDCl 3 , δ): 8.11 (s, 2H), 7.98 (s, 3H), 7.84 (s, 2H), 7.73-7.08 (m, 21H), 3.89 (4H, t), 1.74 (4H, q), 1.28 (20H, m), 0.88 (6H, m)
10) Synthesis of Material 10 (Formula 42)
[0129] A material 10 represented by Formula 42 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and di-naphthalene-2-yl-{4-[10-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolane-2-yl)-anthracene-9-yl]-phenyl}-amine was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.05 (s, 2H), 7.96 (s, 3H), 7.84 (s, 2H), 7.69-6.81 (m, 36H)
11) Synthesis of Material 11 (Formula 46)
[0130] A material 11 represented by Formula 46 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 5 was used instead of the compound 2. 1 H NMR (300 MHz, CDCl 3 , δ): 8.13 (s, 2H), 7.92 (s, 3H), 7.80 (s, 2H), 7.73-7.08 (m, 21H)
12) Synthesis of Material 12 (Formula 52)
[0131] A material 12 represented by Formula 52 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 5 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-(10-naphthalene-2-yl-anthracene-9-yl)-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.15 (s, 2H), 7.98 (s, 3H), 7.79 (s, 2H), 7.75-7.18 (m, 23H)
13) Synthesis of Material 13 (Formula 53)
[0132] A material 13 represented by Formula 53 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 5 was used instead of the compound 2, and 2-(3-tert-butyl-10-naphthalene-1-yl-anthracene-9-yl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.13 (s, 2H), 7.92 (s, 3H), 7.80 (s, 2H), 7.73-7.17 (m, 22H), 1.45 (s, 9H)
14) Synthesis of Material 14 (Formula 56)
[0133] A material 14 represented by Formula 56 was synthesized in the same manner as in the synthesis of the material 1 except that compound 5 was used instead of the compound 2, and 2-{4-[9-naphthalene-2-yl-10-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolane-2-yl)-anthracene-2-yl]-phenyl}-1-phenyl-1H-benzoimidazole was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.13 (s, 2H), 8.05 (s, 3H), 7.95 (s, 2H), 7.91-7.28 (m, 35H)
15) Synthesis of Material 15 (Formula 61)
[0134] A material 15 represented by Formula 61 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 3 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-[4-(10-naphthalene-2-yl-anthracene-9-yl)-phenyl]-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.11 (s, 2H), 7.88 (s, 3H), 7.83 (s, 2H), 7.79-7.01 (m, 29H)
16) Synthesis of Material 16 (Formula 67)
[0135] A material 16 represented by Formula 67 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 5 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-[4-(10-naphthalene-2-yl-anthracene-9-yl)-phenyl]-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.11 (s, 2H), 7.89 (s, 3H), 7.81 (s, 2H), 7.73-7.08 (m, 27H)
17) Synthesis of Material 17 (Formula 69)
[0136] A material 17 represented by Formula 69 was synthesized in the same manner as in the synthesis of the material 1 except that the compound 5 was used instead of the compound 2, and 4,4,5,5-tetramethyl-2-[4-(3-methyl-10-naphthalene-1-yl-anthracene-9-yl)-naphthalene-1-yl]-[1,3,2]dioxaborolane was used instead of 4,4,5,5-tetramethyl-2-(10-phenyl-anthracene-9-yl)-[1,3,2]dioxaborolane. 1 H NMR (300 MHz, CDCl 3 , δ): 8.13 (s, 2H), 7.92 (s, 3H), 7.80 (s, 2H), 7.73-7.08 (m, 20H), 2.44 (s, 3H)
[0137] As shown above, in the embodiments of the present invention, a low molecular weight compound obtained by reacting a cyclopentaphenanthrene compound wherein the 2- or 6-position is functionalized with halogen, borate, aldehyde, hydroxyl, or the like, with another compound, is used as an organoelectroluminescent material. Various substituents can be incorporated into the 4-position of the cyclopentaphenanthrene of the low molecular weight compound, thereby enabling more stable film formation and improving solubility in a solvent.
Evaluation Example
Evaluation of Optical Characteristics of Materials
[0138] The photoluminescence (PL) spectra of the materials 1-9, 11-12, and 16 in a solution phase and a film phase were measured to evaluate the emission characteristics of the materials 1-9, 11-12, and 16.
[0139] In order to evaluate optical characteristics of a solution phase, each of the materials 1-9, 11-12, and 16 was diluted with toluene to a concentration of 10 mM, and the PL spectra of the diluted solutions were measured using an ISC PC1 spectrofluorometer equipped with a xenon lamp. Also, in order to evaluate optical characteristics of a film phase, quartz substrates were prepared and washed with acetone and pure water. Then, the materials 1-9, 11-12, and 16 were spin-coated on the substrates and heated at 110° C. for 30 minutes to form films with a thickness of 1,000 Å. The PL spectra of the films were measured. The results are presented in Table 1 below. As shown in Table 1, it can be seen that the materials 1-9, 11-12, and 16 according to the embodiments of the present invention had emission characteristics suitable for organoelectroluminescent devices.
[0000]
TABLE 1
PL
Material
Solution (λ max )(nm)
Film (λ max )(nm)
1
423, 440
436
2
418, 436
434
3
423, 444
438
4
423, 443
435
5
424, 444
434
6
423, 445
434
7
420, 440
430
8
434, 445
433
9
422, 443
440
11
425, 445
442
12
426, 447
440
16
427, 448
443
Example 1
[0140]
[0141] Organoelectroluminescent devices having the following structure were manufactured using the material 1 as a host of an emitting layer and a compound of Formula 73 above as a dopant of the emitting layer: ITO/PEDOT(400 Å)/material 1: Formula 73 (300 Å)/Alq3 (40 Å)/LiF(10 Å)/Al(2000 Å).
[0142] A 15 Ω/cm 2 (1,000 Å) ITO glass substrate was cut into pieces of 50 mm×50 mm×0.7 mm in size, followed by ultrasonic cleaning in acetone, isopropyl alcohol, and pure water (15 minutes for each) and then UV/ozone cleaning (30 minutes) to form anodes. PEDOT-PSS (Al4083) (Bayer) was coated on the anodes and heated at 110° C. for five minutes in the atmosphere and then at 200° C. for five minutes under a nitrogen atmosphere to form hole injection layers with a thickness of 400 Å. A mixture of 0.1 g of the host material 1 and 0.01 g of the compound of Formula 73 (10 parts by weight of the compound of Formula 73 based on 100 parts by weight of the material 1) were spin-coated on the hole injection layers and heated at 100° C. for 30 minutes to form emitting layers with a thickness of 300 Å. Then, an Alq3 compound was vacuum deposited to a thickness of 40 Å on the emitting layers to form electron transport layers. LiF (10 Å, electron injection layers) and Al (2000 Å, cathodes) were sequentially vacuum-deposited on the electron transport layers to thereby complete organoelectroluminescent devices as illustrated in FIG. 1A . The organoelectroluminescent devices exhibited blue emission of 7,300 cd/m 2 at a voltage of 8 V and efficiency of 2.8 cd/A.
Example 2
[0143] Organoelectroluminescent devices having the following structure were manufactured using the material 2 as a host of an emitting layer and the compound of Formula 73 above as a dopant of the emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 2: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å).
[0144] A 15 Ω/cm 2 (1,000 Å) ITO glass substrate was cut into pieces of 50 mm×50 mm×0.7 mm in size, followed by ultrasonic cleaning in acetone, isopropyl alcohol, and pure water (15 minutes for each) and then UV/ozone cleaning (30 minutes) to form anodes. The compound of Formula 74 (hole injection layers) and α-NPD (hole transport layers) were vacuum deposited on the anodes, and a mixture of the material 2 and the compound of Formula 73 (weight ratio of 100:10) was then vacuum deposited to form emitting layers. Then, an Alq3 compound was vacuum deposited to a thickness of 40 Å on the emitting layers to form electron transport layers. LiF (10 Å, electron injection layers) and Al (2000 Å, cathodes) were sequentially vacuum deposited on the electron transport layers to thereby complete organoelectroluminescent devices as illustrated in FIG. 1B . The organoelectroluminescent devices exhibited blue emission of 12,000 cd/m 2 at a voltage of 7.5 V and efficiency of 6.32 cd/A.
Example 3
[0145] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 3 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 3: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 12,500 cd/m 2 at a voltage of 7.5V and efficiency of 9.4 cd/A. The emission spectra of the organoelectroluminescent devices are illustrated in FIG. 2 .
Example 4
[0146] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 4 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 4 Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 15,400 cd/m 2 at a voltage of 7.5V and efficiency of 8.2 cd/A.
Example 5
[0147] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 5 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 5: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 9,600 cd/m 2 at a voltage of 5.5 V and efficiency of 7.4 cd/A.
Example 6
[0148] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 6 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 6: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 10,000 cd/m 2 at a voltage of 7.0 V and efficiency of 6.7 cd/A.
Example 7
[0149] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 7 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 7: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 8,500 cd/m 2 at a voltage of 6.5 V and efficiency of 8.8 cd/A.
Example 8
[0150] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 8 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 8: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 14,300 cd/m 2 at a voltage of 7.0 V and efficiency of 9.2 cd/A.
Example 9
[0151] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 1 except that the material 9 was used as a host of an emitting layer: ITO/PEDOT(400 Å)/material 9: Formula 73 (300 Å)/Alq3 (40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 9,400 cd/m 2 at a voltage of 8.0V and efficiency of 4.7 cd/A.
Example 10
[0152] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 11 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 11: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 12,200 cd/m 2 at a voltage of 7.5V and efficiency of 8.8 cd/A.
Example 11
[0153] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 12 was used as a host of an emitting layer: ITO/Formula 71 (200 Å)/α-NPD(300 Å)/material 12: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 9,100 cd/m 2 at a voltage of 7.0V and efficiency of 6.8 cd/A.
Example 12
[0154] Organoelectroluminescent devices having the following structure were manufactured in the same manner as in Example 2 except that the material 16 was used as a host of an emitting layer: ITO/Formula 74 (200 Å)/α-NPD(300 Å)/material 16: Formula 73 (300 Å)/Alq3(40 Å)/LiF(10 Å)/Al(2000 Å). The organoelectroluminescent devices exhibited blue emission of 10,200 cd/m 2 at a voltage of 6.5 V and efficiency of 5.4 cd/A.
[0155] The above Examples show that materials according to the embodiments of the present invention have good EL characteristics as phosphorescent and fluorescent materials.
[0156] A compound of Formula 1 according to the embodiment of the present invention is adapted for both dry and wet processes, and has good emission characteristics and thermal stability. Therefore, the use of the compound of the present invention enables to produce an organoelectroluminescent device having a low driving voltage and good color purity and efficiency.
[0157] Other embodiments of the invention, including modifications and adaptions of the disclosed embodiments, will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. The foregoing descriptions of implementations of the invention have been presented for purposes of illustration and description. The descriptions are not exhaustive and do not limit the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practicing the invention. | A cyclopentaphenanthrene-based compound is easy to prepare and excellent in solubility, color purity, and color stability. The cyclopentaphenanthrene-based compound is useful as a material for forming an organic layer, in particular, an emitting layer, in an organoelectroluminescent device, and as an organic dye or an electronic material such as a nonlinear optical material. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of International Patent Application No. PCT/CN2013/077007 with an international filing date of Jun. 8, 2013, designating the United States, now pending, and further claims priority benefits to Chinese Patent Application No. 201210188794.X filed Jun. 8, 2012. The contents of all of the aforementioned applications, including any intervening amendments thereto, are incorporated herein by reference. Inquiries from the public to applicants or assignees concerning this document or the related applications should be directed to: Matthias Scholl P. C., Attn.: Dr. Matthias Scholl Esq., 245 First Street, 18th Floor, Cambridge, Mass. 02142.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the field of shale gas exploitation, and more particularly to a pneumatic fracturing method and a system for exploiting shale gas.
2. Description of the Related Art
A typical method for exploiting the shale gas and oil resource generally adopts the hydraulic fracturing technology, which includes: pressing a fracturing fluid into an oil well, fracturing a rock formation to produce fissure channels having high flow conductivity, and injecting a proppant (mainly quartz sand) to support factures, thereby further improving the oil-gas recovery factor. As the fracturing fluid used in the exploitation of the shale gas includes 98 wt. % of water and 2 wt. % of chemical additives, problems as follows occur:
1) The water consumption is tremendous, so that the hydraulic fracturing technology is not applicable to water shortage or water deficit areas where the shale gas distributes.
2) Although the hydraulic fracturing has a high fracturing pressure, with a maximum of 140 megapascal. However, main cracks forming under the action of the hydraulic fracturing has a limited number and the form thereof is single, which result in a low degree of fracturing of the shale formation. Besides, as the fluid has a large surface tension and molecules and poor permeability, it is difficult to introduce the fluid into the compact fissures in the shale formation or to improve the permeability of oil-gas in the shale formation, thereby resulting in low recovery factor.
3) The chemical additives and the shale gas (mainly methane) in the fracturing fluid enter the ground water, seriously pollute the ecological environment, and seriously restrict the exploitation of the shale gas.
SUMMARY OF THE INVENTION
In view of the above-described problems, it is one objective of the invention to provide a pneumatic fracturing method and a system for exploiting shale gas for facilitating the shale gas exploitation in water shortage or deficit areas, improving recovery factor of the shale gas, and protecting the ecological environment.
To achieve the above objective, in accordance with one embodiment of the invention, there is provided a pneumatic fracturing method for exploiting shale gas. The method comprises: 1) applying a compressed gas for a first period of time at a first pressure to a shale formation; 2) applying the compressed gas for a second period of time at a second pressure to the shale formation; and 3) repeating steps 1) and 2) to produce fissures in the shale formation. A temperature of the compressed gas is at least 80° C., a maximum pressure of the compressed gas is at least 25 megapascal, and a minimum pressure of the compressed gas is between ¼ and ⅓ of the maximum pressure. The fissures mean that the shale formation cracks and tight micro pores in the shale formation communicate with each other, thereby possessing conditions for exploiting the shale gas.
In a class of this embodiment, the compressed gas is compressed air or compressed carbon dioxide. When the compressed air is adopted, a temperature thereof is at least 150° C., and a maximum pressure thereof is at least 45 megapascal. In order to improve the fracture effect of the shale formation, a water content of the compressed air is preferably controlled between 10 and 50 volume %. When the compressed carbon dioxide is adopted, a temperature thereof is at least 80° C. and a maximum pressure thereof is at least 25 megapascal.
In a class of this embodiment, the method specifically comprises the following steps:
A) drilling a vertical well and a horizontal well communicating with the vertical well in the shale formation, and installing a gas transporting pipeline having insulation property in the vertical well and the horizontal well; wherein an outer diameter of the gas transporting pipeline is smaller than an inner diameter of the vertical well and an inner diameter of the horizontal well; ventholes are arranged on a wall of the gas transporting pipeline installed in the horizontal well; and an annular space forms between an inner surface of the horizontal well and an outer surface of the gas transporting pipeline, and annular occluders are arranged in the annular space at an interval of between 30 and 50 m to form a plurality of annular gas chambers;
B) injecting the compressed gas satisfying the maximum pressure to the gas transporting pipeline, and maintaining the pressure for between 0.5 and 1 hr, and decreasing the pressure in the gas transporting pipeline to satisfy the minimum pressure after the holding time, whereby allowing the compressed gas of the maximum pressure and the compressed gas of the minimum pressure to alternately fill the annular gas chambers and act on the shale formation; and
C) repeating step B) for several times to produce fissures in the shale formation.
In accordance with another embodiment of the invention, there is provided a first pneumatic fracturing system for exploiting shale gas. The system comprises: a compressor; a booster; a pressure control system, the pressure control system comprising a pressure controller, a first control valve, and a second control valve; and a gas transporting pipeline, the gas transporting pipeline comprising a gas inlet pipe and a gas outlet pipe. The first control valve is disposed on the gas inlet pipe of the gas transporting pipeline. The second control valve is disposed on the gas outlet pipe of the gas transporting pipeline. A gas outlet of the compressor communicates with a gas inlet of the booster via a pipe fitting. A gas outlet of the booster communicates with a gas inlet of the first control valve via a pipe fitting. The pressure controller is connected to the compressor, the booster, the first control valve, and the second control valve via data lines for controlling formation of the compressed gas and alternative variation and holding of the pressure in the gas transporting pipeline. The pneumatic fracturing system of such structure is applicable to conditions that the temperature in the process of compressing the gas is capable of allowing the compressed gas to reach the required high temperature.
In accordance with another embodiment of the invention, there is provided a second pneumatic fracturing system for exploiting shale gas. The system comprises: a compressor; a booster; a heater; a pressure control system, the pressure control system comprising a pressure controller, a first control valve, and a second control valve; and a gas transporting pipeline, the gas transporting pipeline comprising a gas inlet pipe and a gas outlet pipe. The first control valve is disposed on the gas inlet pipe of the gas transporting pipeline. The second control valve is disposed on the gas outlet pipe of the gas transporting pipeline. A gas outlet of the compressor communicates with a gas inlet of the booster via a pipe fitting. A gas outlet of the booster communicates with a gas inlet of the heater via a pipe fitting. A gas outlet of the heater communicates with a gas inlet of the first control valve via a pipe fitting. The pressure controller is connected to the compressor, the booster, the heater, the first control valve, and the second control valve via data lines for controlling formation of the compressed gas and alternative variation and holding of the pressure in the gas transporting pipeline. The pneumatic fracturing system of such structure is applicable to conditions that the temperature produced in the process of compressing the gas is incapable of allowing the compressed gas to reach the required high temperature.
In a class of this embodiment, the system further comprises: a dehumidifier. A gas inlet of the dehumidifier communicates with a gas outlet of the compressor via a pipe fitting. A gas outlet of the dehumidifier communicates with a gas inlet of the booster via a pipe fitting. The dehumidifier is connected to the pressure controller via a data line.
In a class of this embodiment, the pressure controller is a computer installed with a control software. Under the control of the pressure controller, an atmospheric gas is preliminarily compressed by the compressor to between 1 and 10 megapascal. The water content of the compressed gas from the compressor is decreased by the dehumidifier until a required water content is satisfied. The compressed gas from the compressor or the compressed gas from the dehumidifier is pressurized by the booster to allow the compressed gas to satisfy the maximum pressure. If the temperature of the compressed gas after pressurization by the booster is lower than the required temperature, the heater is used to heat the compressed gas from the booster to make the compressed gas meet the required temperature. Under the control of the pressure controller, the first control valve is open or close, and the second control valve is open or close. The first control valve is used to inject the compressed gas satisfying the maximum pressure into the gas transporting pipeline installed in the vertical well and the horizontal well drilled in the shale formation. The second control valve is used to exhaust the gas and to decrease the gas pressure in the gas transporting pipeline.
Advantages according to embodiments of the invention are summarized as follows:
1. The method of the invention provides a technical solution different from the prior art in the exploitation of the shale gas. Not only is the problem solved that the shale gas is unable to be exploited in water shortage or deficit areas, but also it is beneficial for the protection of the ecological environment.
2. As the method of the invention utilizes the high temperature and high pressure gases to make brittle fatigue failures occur in the shale formation under the action of alternative different pressures thereby resulting in fissures, thus, the tight micro pores in the shale formation grow and communicate with each other. The permeability of the shale formation is largely improved, the desorption of the shale gas is facilitated, activities of oil and gas molecules are enhanced, that is, the filtration and the dissipation capacity of the oil and gas molecules are increased, thereby increasing the recovery efficiency of the shale gas.
3. The system of the invention is capable of conducting multi-stage gas compression and using multi sets in parallel to extract the shale gas, thereby ensuring the fracturing pressure and the thermal energy of the gas.
4. The system of the invention is capable of controlling the aptitude and frequency of the compressed gas to continuously enlarge the fissures in the shale formation and widespread the fissures to deep regions, thereby broadening the channel and the range of the eruption of the shale oil and gas.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described hereinbelow with reference to the accompanying drawings, in which:
FIG. 1 is a first layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 2 is a structure diagram of fissures formed in a shale formation using a first system layout of FIG. 1 ;
FIG. 3 is a second layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 4 is a structure diagram of fissures formed in a shale formation using a second system layout of FIG. 3 ;
FIG. 5 is a third layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 6 is a structure diagram of fissures formed in a shale formation using a third system layout of FIG. 5 ;
FIG. 7 is a fourth layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 8 is a structure diagram of fissures formed in a shale formation using a fourth system layout of FIG. 7 ;
FIG. 9 is a fifth layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 10 is a structure diagram of fissures formed in a shale formation using a fifth system layout of FIG. 9 ;
FIG. 11 is a sixth layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 12 is a structure diagram of fissures formed in a shale formation using a sixth system layout of FIG. 11 ;
FIG. 13 is a seventh layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention;
FIG. 14 is a structure diagram of fissures formed in a shale formation using a seventh system layout of FIG. 13 ;
FIG. 15 is an eighth layout diagram of a pneumatic fracturing system for exploiting shale gas in accordance with one embodiment of the invention; and
FIG. 16 is a structure diagram of fissures formed in a shale formation using a eighth system layout of FIG. 15 .
In the drawings, the following reference numbers are used: 1 . Compressor; 2 . Booster; 3 . Heater; 4 . Pressure controller; 5 . Vertical well; 6 . Horizontal well; 7 . Occluder; 8 . Gas transporting pipeline; 9 . Venthole; 10 . Dehumidifier; 11 . First control valve; 12 . Second control valve; and 13 . Shale fissure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
For further illustrating the invention, experiments detailing a pneumatic fracturing method and a system for exploiting shale gas are described below. It should be noted that the following examples are intended to describe and not to limit the invention.
A compressor herein employs a SF-10/250 gas compressor (air compressor) or a VW-16.7/40 (carbon dioxide compressor) manufactured by Bengbu Aipu Compressor Plant, China. A booster employs an ST140-7.5GH booster manufactured by Jinan Shineeast Fluid System Device Co. LTD. A heater employs a QL-GD-685 gas heater manufactured by Qili Power Equipment Co. LTD. A dehumidifier employs an HZXW regenerative adsorption dryer manufactured by Hanzheng Gas Source Equipment Co. LTD. Both a first control valve and a second control valve employ PO high pressure pneumatic ball valves manufactured by POLOVO. A pressure controller is an industrial computer installed with a control software.
Example 1
A pneumatic fracturing system is shown in FIG. 1 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed air of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and a horizontal well 6 communicating with the vertical well 5 are drilled in the shale formation, and a gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal well 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of the horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in the horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 30 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 and the booster 2 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure air to reach a pressure of 5 megapascal. The booster 2 further pressurizes the compressed air from the compressor 1 to form compressed air having a temperature of exceeding 150° C. and a pressure of 45 megapascal, the pressure of which reaches the maximum pressure set in this example. The compressed air of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 0.5 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the air pressure in the gas transporting pipe 8 to 15 megapascal, which is the minimum pressure set in this example. Thus, the compressed air of 45 megapascal and the compressed air of 15 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 7 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal well 6 are shown in FIG. 2 .
Example 2
A pneumatic fracturing system is shown in FIG. 3 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed carbon dioxide of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and a horizontal well 6 communicating with the vertical well 5 are drilled in the shale formation, and a gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal well 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of the horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in the horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 40 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , a heater 3 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the heater 3 via a pipe fitting. A gas outlet of the heater 3 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the heater 3 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 , the booster 2 , and the heater 3 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure carbon dioxide to reach a pressure of 2 megapascal; the booster 2 pressurizes the compressed carbon dioxide from the compressor 1 to reach a pressure of 25 megapascal; and the heater 3 heat the pressurized carbon dioxide to a temperature of 100° C. to yield the compressed carbon dioxide of a maximum pressure set in this example. The compressed carbon dioxide of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 1 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the gas pressure in the gas transporting pipe 8 to 8 megapascal, which is the minimum pressure set in this example. Thus, the compressed carbon dioxide of 25 megapascal and the compressed carbon dioxide of 8 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 10 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal well 6 are shown in FIG. 4 .
Example 3
A pneumatic fracturing system is shown in FIG. 5 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed air of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and a horizontal well 6 communicating with the vertical well 5 are drilled in the shale formation, and a gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal well 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of the horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in the horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 50 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , a heater 3 , dehumidifier 10 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the dehumidifier 10 via a pipe fitting. A gas outlet of the dehumidifier 10 communicates with a gas inlet of the booster 2 a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of a heater 3 via a pipe fitting. A gas outlet of the heater 3 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the heater 3 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 , the dehumidifier 10 , the booster 2 , and the heater 3 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure air to reach a pressure of 1 megapascal; the dehumidifier 10 decreases a water content of the compressed air from the compressor 1 to 10 volume %; the booster 2 pressurizes the compressed air from the dehumidifier 10 to reach a pressure of 50 megapascal; and the heater 3 heats the pressurized air from the booster 2 to a temperature of 180° C. to yield the compressed air of a maximum pressure set in this example. The compressed air of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 1 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the air pressure in the gas transporting pipe 8 to 14 megapascal, which is the minimum pressure set in this example. Thus, the compressed air of 50 megapascal and the compressed air of 14 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 8 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal well 6 are shown in FIG. 6 .
Example 4
A pneumatic fracturing system is shown in FIG. 7 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed air of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and two horizontal wells 6 are drilled in the shale formation. The two horizontal wells 6 communicate with the vertical well 5 and are arranged at a certain interval on the same side of the vertical well 5 . A gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal wells 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of each horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in each of the two horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 30 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , a heater 3 , dehumidifier 10 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the dehumidifier 10 via a pipe fitting. A gas outlet of the dehumidifier 10 communicates with a gas inlet of the booster 2 a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of a heater 3 via a pipe fitting. A gas outlet of the heater 3 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the heater 3 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 , the dehumidifier 10 , the booster 2 , and the heater 3 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure air to reach a pressure of 1 megapascal; the dehumidifier 10 decreases a water content of the compressed air from the compressor 1 to 50 volume %; the booster 2 pressurizes the compressed air from the dehumidifier 10 to reach a pressure of 45 megapascal; and the heater 3 heats the pressurized air from the booster 2 to a temperature of 180° C. to yield the compressed air of a maximum pressure set in this example. The compressed air of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 0.5 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the air pressure in the gas transporting pipe 8 to 15 megapascal, which is the minimum pressure set in this example. Thus, the compressed air of 45 megapascal and the compressed air of 15 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 3 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal well 6 are shown in FIG. 8 .
Example 5
A pneumatic fracturing system is shown in FIG. 9 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed carbon dioxide of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and two horizontal wells 6 are drilled in the shale formation. The two horizontal wells 6 communicate with the vertical well 5 and are arranged at a certain interval on the same side of the vertical well 5 . A gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal wells 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of each horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in each of the two horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 40 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , a heater 3 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the heater 3 via a pipe fitting. A gas outlet of the heater 3 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the heater 3 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 , the booster 2 , and the heater 3 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure carbon dioxide to reach a pressure of 1 megapascal; the booster 2 pressurizes the compressed carbon dioxide from the compressor 1 to reach a pressure of 25 megapascal; and the heater 3 heat the pressurized carbon dioxide to a temperature of 80° C. to yield the compressed carbon dioxide of a maximum pressure set in this example. The compressed carbon dioxide of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 1 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the gas pressure in the gas transporting pipe 8 to 8 megapascal, which is the minimum pressure set in this example. Thus, the compressed carbon dioxide of 25 megapascal and the compressed carbon dioxide of 8 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 7 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal wells 6 are shown in FIG. 10 .
Example 6
A pneumatic fracturing system is shown in FIG. 11 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed air of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and two horizontal wells 6 are drilled in the shale formation. The two horizontal wells 6 communicate with the vertical well 5 and are arranged at a certain interval on the same side of the vertical well 5 . A gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal wells 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of each horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in each of the two horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 40 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 and the booster 2 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure air to reach a pressure of 1 megapascal. The booster 2 further pressurizes the compressed air from the compressor 1 to form compressed air having a temperature of exceeding 150° C. and a pressure of 60 megapascal, the pressure of which reaches the maximum pressure set in this example. The compressed air of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 1 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the air pressure in the gas transporting pipe 8 to 20 megapascal, which is the minimum pressure set in this example. Thus, the compressed air of 60 megapascal and the compressed air of 20 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 3 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal wells 6 are shown in FIG. 12 .
Example 7
A pneumatic fracturing system is shown in FIG. 13 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed carbon dioxide of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and two horizontal wells 6 are drilled in the shale formation. The two horizontal wells 6 communicate with the vertical well 5 and are arranged at a certain interval on two sides of the vertical well 5 . A gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal wells 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of each horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in each of the two horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 50 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , a heater 3 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the heater 3 via a pipe fitting. A gas outlet of the heater 3 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the heater 3 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 , the booster 2 , and the heater 3 are started to enable the first control valve 11 to be in an open state. The compressor 1 preliminarily compresses normal pressure carbon dioxide to reach a pressure of 1 megapascal; the booster 2 pressurizes the compressed carbon dioxide from the compressor 1 to reach a pressure of 45 megapascal; and the heater 3 heat the pressurized carbon dioxide to a temperature of 80° C. to yield the compressed carbon dioxide of a maximum pressure set in this example. The compressed carbon dioxide of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 0.5 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the gas pressure in the gas transporting pipe 8 to 12 megapascal, which is the minimum pressure set in this example. Thus, the compressed carbon dioxide of 45 megapascal and the compressed carbon dioxide of 12 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 5 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal wells 6 are shown in FIG. 14 .
Example 8
A pneumatic fracturing system is shown in FIG. 15 , and a pneumatic fracturing method for exploiting shale gas using the system employs compressed air of two different pressures to alternately act on a shale formation. The method is conducted as follows:
A) A vertical well 5 and two horizontal wells 6 are drilled in the shale formation. The two horizontal wells 6 communicate with the vertical well 5 and are arranged at a certain interval on two sides of the vertical well 5 . A gas transporting pipeline 8 having insulation property is installed in the vertical well 5 and the horizontal wells 6 . An outer diameter of the gas transporting pipeline 8 is smaller than an inner diameter of the vertical well 5 and an inner diameter of each horizontal well 6 . Ventholes 9 are arranged on a wall of the gas transporting pipeline 8 installed in each of the two horizontal well 6 . An annular space forms between an inner surface of the horizontal well 6 and an outer surface of the gas transporting pipeline 8 , and annular occluders 7 are arranged in the annular space at an interval of 50 m to form a plurality of annular gas chambers.
The pneumatic fracturing system for exploiting shale gas comprises: a compressor 1 , a booster 2 , and a pressure control system. The pressure control system comprises: a pressure controller 4 , a first control valve 11 , and a second control valve 12 . The first control valve 11 is disposed on a gas inlet pipe of the gas transporting pipeline 8 . The second control valve 12 is disposed on a gas outlet pipe of the gas transporting pipeline 8 . A gas outlet of the compressor 1 communicates with a gas inlet of the booster 2 via a pipe fitting. A gas outlet of the booster 2 communicates with a gas inlet of the first control valve 11 via a pipe fitting. The pressure controller 4 is connected to the compressor 1 , the booster 2 , the first control valve 11 , and the second control valve 12 via data lines.
B) The pressure controller 4 is operated, and the compressor 1 and the booster 2 are started to enable the first control valve 11 to be in an open sate. The compressor 1 preliminarily compresses normal pressure air to reach a pressure of 10 megapascal. The booster 2 further pressurizes the compressed air from the compressor 1 to form compressed air having a temperature of exceeding 150° C. and a pressure of 45 megapascal, the pressure of which reaches the maximum pressure set in this example. The compressed air of the maximum pressure is injected into the gas transporting pipe 8 through the first control valve 11 and the maximum pressure is maintained for 1 hr. After the holding time, the first control valve 11 is closed and the second valve 12 is opened under the control of the pressure controller 4 to decrease the air pressure in the gas transporting pipe 8 to 15 megapascal, which is the minimum pressure set in this example. Thus, the compressed air of 45 megapascal and the compressed air of 15 megapascal alternately fill each annular gas chamber and act on the shale formation.
C) Operations of step B) is repeated for 7 days under the control of the pressure controller 4 . And fissures formed in the shale formation surrounding the horizontal wells 6 are shown in FIG. 16 .
While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. | A pneumatic fracturing method for exploiting shale gas, the method including: 1) applying a compressed gas for a first period of time at a first pressure to a shale formation; 2) applying the compressed gas for a second period of time at a second pressure to the shale formation; and 3) repeating steps 1) and 2) to produce fissures in the shale formation. A temperature of the compressed gas is at least 80° C. A maximum pressure of the compressed gas is at least 25 megapascal, and a minimum pressure of the compressed gas is between ¼ and ⅓ of the maximum pressure. | 4 |
BACKGROUND OF THE INVENTION
The disclosed structure is a Continuation-In-Part of U.S. Pat. application No. 715,912 filed Jun. 14, 1991, issuing Sep. 28, 1993, as U.S. Pat. No. 5,247,774 on a TOWER CONSTRUCTED OF PULTRUDED COMPOSITES. That patent was a continuation in part of U.S. application No. 07/541,547 filed Jun. 21, 1990, issued on Jun. 18, 1991 as U.S. Pat. No. 5,024,036 on an invention entitled INTERLOCKIING SUPPORT STRUCTURES, which was a Continuation-in-Part of U.S. application No. 07/231,379 filed Aug. 12, 1988, issued on Feb. 12, 1991 as U.S. Pat. No. 4,991,726 on an invention entitled SUPPORT STAND, that was a Continuation-in-Part of both: U.S. application No. 07/137,101 filed Dec. 23, 1987, issued on Feb. 28, 1989, as U.S. Pat. No. 4,809,146 on an ENCLOSURE WITH INTERLOCKING FRAME JOINTS and U.S. application No. 07/137,100 filed Dec. 23, 1987, issued on May 2, 1989 as U.S. Pat. No. 4,825,620, on a ATRUCTURAL SUPPORT OF INTERLOCKING LATTICE CONSTRUCTION, both of which were Continuations-in-part of U.S. application No. 06/848,573, filed Apr. 7, 1986, issued Dec. 29, 1987 as U.S. Pat. No. 4,715,503 on an INTERLOCKING JOINT WINE RACK. This application is also a Continuation-In-Part of U.S. application No. 08/007,079 filed Jan. 29, 1993, issued Jun. 14, 1994 as U.S. Pat. No. 5,319,901, on a Bifurcated Column Joint System For Electrical Transmission Tower and U.S. application No. 07/828,499 filed Jan. 31,1992, issued Feb. 15, 1994 as U.S. Pat. No. 5,285,613, on a Pultruded Joint System and Tower Structure Made Therewith. The parent invention combined the fields of high voltage transmission towers and pultruded composite construction, and continued a series of developments relating to the fabrication of relatively large structures formed from pultruded composites. Particular attention was directed toward the development of effective joining techniques in a field in which steel construction has dominated, but using materials for which the steel joining techniques of bolting and welding are unsuitable.
A composite can be laid up as layers of fibers or fiber cloth or cords bonded with a polymer resin, or in some applications it can be pultruded. A pultruded composite is made by drawing a bundle of fibers through a resin bath and then through a die, in which it is heat-cured to a smooth, hard member that is usually a thermal and electrical insulator as well as being resistant to corrosive chemicals. The resulting product is tough and virtually immune from corrosion and chemical deterioration.
Currently, virtually all transmission towers are made of steel. However, certain undesirable performance limitations are inherent in steel, the foremost being high electrical conductivity. Inasmuch as it is the role of the tower to support, and isolate from ground, conductors carrying 200,000 volts or more, the towers must be large, both to separate the individual conductors from each other and from the steel structure, and to accommodate inter-tower line sag. The high conductivity of the steel structural supports mitigates against these goals, increasing flashover potential and posing a chronic safety hazard to the line maintenance crew as well. Steel towers also inevitably suffer from deterioration from rust and corrosion and must be coated regularly and eventually replaced, often at great expense if the site is remote and inaccessible.
A consideration involving transmission towers of current and increasing concern regards the powerful electromagnetic field (EMF) in the immediate vicinity of the lines. EMF is suspected of being linked to cancer in humans who live or work under the conductors on a daily basis. Whether or not this alleged link is ever substantiated, the current public perception that it may be true causes problems right now, involving land values, lawsuits, the anxiety for property owners and those who work or dwell in the immediate vicinity of high voltage lines. While steel used in towers may not directly enhance EMF radiation, partly due to its conductivity the out-of-phase conductors must be widely spaced apart, which minimizes the flashover potential but also reduces the natural phase cancellation that can be achieved with compact electrical conductors. These factors warranted consideration of alternative techniques and materials for tower construction, and composites have characteristics that make them worth investigating.
Certain problems must be overcome when using composites in place of steel, or in place of wood in the case of utility poles. Paramount among these is the difficulty of joining composite members with structurally sound joints. When composite members are fastened with conventional fasteners such as bolts and screws, joint strength is generally unacceptable. This problem has been met and largely overcome in the disclosure of the parent patent and other related applications filed by applicant which disclose ways of engaging cross members in specially designed corner columns without the need for holes or bolts.
Another challenge in using pultruded composites for structural members stems from the nature of the pultrusion process. Pultrusion is an ideal process for making infinitely long, strong members of uniform cross-section with very low production costs beyond materials costs. However, the pultruded product has no taper, and current state-of-the-art techniques fail to provide for tapered members and possibly never will. When making tall structures such as utility poles or towers however, it is necessary or desirable to taper the structure for weight reduction and optimum resistance to bending moments, not to mention aesthetics near urban centers. A utility tower or tall pole having the same planform dimensions top-to-bottom would be a poor design.
It is the purpose of this disclosure to address the problem of using constant-planform pultrusions to produce a general purpose elongated tower- or pole-type structure completely tapered despite the fact that it is composed entirely of pultruded members.
SUMMARY OF THE INVENTION
The invention may be used in any application in which a tall supporting structure is required, and preferably in an application in which the beneficial qualities of high dielectric constant, relatively high strength -to-weight ratio and corrosion resistance are desirable. Typical uses are for a radio or microwave, etc., tower, a utility pole and a high-voltage transmission tower, all of which are made substantially completely from composite pultrusions. These implementations have the advantage of superiority to steel in size and weight for the same performance, weighing about half as much as an equivalent conventional steel structure and having overall dimensions on the order of two-thirds of comparable current configurations of steel towers in the high-voltage tower embodiment. The narrower right-of-way required for a transmission line supported by these compact towers and the reduction of EMF resulting from the elevated level of phase cancellation due to the narrower spacing between the conductors is realized by the tower configuration. For smaller structures, the advantages of greater longevity inherent in the highly chemical- and UV-resistant composite poles can be enjoyed without being relegated to a member that must be equally wide at the top as at the bottom.
To achieve these advantages, the disclosed construction uses pultruded ribs which themselves are of uniform cross-section, but which are tapered uniformly or in a curve to optimize the overall configuration and permanently restrained in the tapered shape by a monocoque outer sheathing or an internal rigidifying structure, or both.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a somewhat diagrammatic front elevation view of a support made according to the invention;
FIG. 2 is an elevation view of a prior art tower which is visually similar to the composite tower of FIG. 1 but is fabricated of steel;
FIG. 3 is a front elevation view of the tower of FIG. 1 shown in greater detail;
FIG. 4 is a vertically compressed elevation view of the structure shown with the central portion omitted and a portion of the skin torn away to reveal the interior support structure;
FIG. 5 is a section taken along line 5--5 of FIG. 4;
FIG. 6 is an elevation view partially in section of a central fragmentary portion of the structure with the skin partially peeled away;
FIG. 7 is a diagrammatic horizontal section taken through a structure similar to that of the remaining figures but square in cross-section; and,
FIG. 8 is a somewhat diagrammatic horizontal cross section through the hexagonal unit illustrating only the braces and skin and sections of the vertical members.
FIG. 9 is an exploded side elevation view illustrating the manner in which the horizontal cross members are interconnected with the upright longitudinal ribs.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A typical prior art tower is indicated at 10. It consists of a tapered steel structure 12, with extended support arms 14. Strings of insulators indicated at 16 support the power lines 18. A "peak" 20 supports one or more lightning shield wires, not shown. The structure in FIG. 2 is all fabricated steel, is generally multi-sided, and is welded together on several edges.
The invention is shown in FIG. 1. Although similar in appearance to the prior art in the illustrated embodiment, it is vastly different, being made of pultruded composites. The towers of FIGS. 1 and 2 are configured in conformity to industry standard specfications for towers supporting high voltage wire conductors intended to carry 69 kilovolts and above, with the wires spaced apart minimum distances X in the steel version of FIG. 2 and X/2 in the composite version as predetermined by industry standards applicable to the 69-KV voltage class and above. The conductor-to-tower spacing minimum for towers in this class is indicated at B in FIG. 1, which is about half of the comparable spacing in the steel tower (the spacing is not indicated by number or letter in FIG. 2).
The industry standards for the spacing of the phases, or individual conductors, is fairly narrowly defined by the line voltage rating. The rule is expressed as, the wet-insulation flashover should be four times the line-to-ground voltage. For example a three-conductor tower carrying 345 kilovolts is first divided by the square root of three, which equals approximately 200 kilovolts. Since four times two hundred equals 800 kilovolts, an insulator string is selected to space the conductor from the metal tower sufficiently to have a minimum of 800 kilovolt flashover with wet insulation. At 345 kv, the conductors must be approximately 110 inches from ground potential, which includes all of the tower in addition to the actual ground. Referring to the drawing of FIG. 1, a form of the new tower 24 can be seen as compared to the standard equivalent metal tower 10 of FIG. 2. By eliminating the conductive material in the tower, it can be seen that the wires can be brought in to approximately half of their former spacing in the new composite tower, from spacing "X" in the steel tower to "1/2 X" in the composite tower. The same approximate ratio of reduction in spacing applies to the conductor-to-frame spacing and the vertical conductor-to-conductor spacing.
This same efficiency in spacing is apparent in FIG. 1 as the tower 24 is approximately 80% as high as the tower of FIG. 2. The closest conductor to ground level, 18, remains at the same height in both configurations, to ensure with conductor sag, the minimum safe height above ground level is achieved. However, in FIG. 1, a compaction of conductors, or phases, is possible because the tower is a fully insulative composite and the design criteria of minimum flashover, phase-to-ground, is no longer a limiting criteria. Thus the lengths of the insulators 17 in FIG. 1 are half the length of the insulators 16 in FIG. 2.
The insulator length of FIG. 1 could be reduced to half the typical length required of a steel tower as shown, but it could alternatively be eliminated as a separate unit. This could be achieved by adding silicone rubber sheds (not shown), a common "tracking" resistant skirt material used in high voltage polymer insulators, to extended rods which are an integral structure of the tower at points such as that indicated at 26 in FIG. 1. In lieu of separate insulators, the sheds that are generally installed on insulator rods will be installed directly on a portion of the tower adjacent to the attachment point of the conductor. This attachment point is shown on just one arm of the tower in FIG. 1 at 26 but would of course replace all of the hanging insulators.
By compacting the conductors, the tower height is reduced, the right-of-way owned by the entity transmitting electricity is more compact, energy is transmitted more efficiently due to lower inductive reactance, the electromagnetic field (EMF) at ground level is reduced, and further reduction in weight is achieved.
FIG. 3 shows a front elevation of the tower 34 which is installed on a concrete foundation pad 36 with bolts 38 through a flange 40. A cap 42 is shown on the top of the tower to prevent moisture from entering the structure. Although only three conductors 18 and cross arm supports 14 are required for a single circuit, many times two circuits are strung through a right-of-way and this requires, in three phase systems, the six cross arms 14 and six conductors 18 shown in FIG. 3. From external appearances the tapered trunk structure of FIG. 3 would look like any typical steel tapered pole that is currently fabricated hollow with substantially thick walls. The difference is the composite tapered trunk structure of FIG. 3 is made with an external skin 44 which is bonded or fastened to an internal array of cross members and longitudinal ribs, not unlike the composite cross members and support legs of the previously referenced patent. This external skin is an aesthetic covering, however its primary purpose is structural. The external skin 44 absorbs bending stresses, in addition to the internal cross members and longitudinal ribs, and allows a narrower taper, and thus smaller foundation area, than would be required without the external skin. The external skin 44 is pultruded composite material fabricated in continuous sheets and then machined in a tapered trapezoidal shape. The ribs and cross bracing members define trapezoidal sections as shown in FIG. 6, with the four faces together defining one of several vertically consecutive cells with vertically aligned cell faces defining continuous trunk faces. The trapezoidal skin panels are mounted over said respective trunk faces in one embodiment, as shown in FIG. 4, fitting thereon one-to-one.
FIG. 4 shows an elevation view of the tapered composite support structure 34 with the top and bottom of the structure shown and the missing central portion indicated as dashed line 46. Shown in this figure is the external skin 44 and the internal longitudinal ribs 48 and cross members 50. Also shown is the foundation 40, foundation tie down bolts 38 and the cap 42. There are six longitudinal ribs in the structure of FIG. 4, although the number of ribs could vary from three to eight or more. Section 5--5 of FIG. 4 is shown in FIG. 5 to illustrate this.
FIG. 5 shows internal details of the tapered composite elevated support structure. Six longitudinal ribs 48 have cross members 50 interconnected with the ribs and having snap-in detent structure cooperating with mating brace detent structure defined by the cross bracing members such that the ribs and cross bracing structure interconnect substantially without fasteners. The ribs are designed to interface with the cross members at 120 degrees angle and are unique for a six sided structure. The external skin 44 is shown, which as stated is trapezoidal and extends the entire length of the trunk structure either as consecutive trapezoids or as a single monolithic panel. Also shown is the mounting flange 40 and the mounting bolts 38.
FIG. 6 is an elevation view of a four sided tapered composite elevated support structure 56 with external skin 64 and internal longitudinal ribs 62 and internal cross members 60.
FIG. 7 is a cross section 4--4 of FIG. 6. Shown in cross section are the four longitudinal ribs 62, which as stated are unique for this application, that is a four sided tapered composite elevated support structure. Shown also are the internal cross members 60 and the external skin 64.
FIG. 8 shows an alternate configuration of a cross section of a six sided structure with longitudinal ribs 48, cross members 50 and skin 44.
FIG. 9 is an exploded side elevation view that illustrates the manner in which the longitudinal ribs 48 and cross members 50 in FIG. 4 are secured to each other. The snap-in detent structure 52 is comprised of the tip 51 on cross member 50 that is received in recess 49 of longitudinal ribs 48. | A high voltage electrical transmission line support structure is constructed virtually completely from glass reinforced composites, comprised of vertical ribs, reinforcing cross bracing members and a skin composed of composite panels, enabling the reduction in elevation and closer spacing of conductors, and the creation of a smaller support structure weighing half or less the weight of a steel tower of the same power rating. The resulting structure requires substantially less ground right-of-way, and EMF radiation is attenuated in the immediate tower area due to the closer phase spacing. | 4 |
This application is a divisional of application Ser. No. 08/863,620, filed on May 27, 1997, now U.S. Pat. No. 5,889,757 the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a laminated disc such as a DVD (Digital Video Disc) and a turntable on which laminated disc is placed for reproduction of information.
2. Description of Prior Art
FIG. 20 is a cross-sectional view of a prior art turntable which is disclosed in Japanese Patent Preliminary Publication No. 8-7425. A turntable 102 has a hub 105 into which a motor shaft 104 Is press-fitted or securely bonded to drive the turntable 102 in rotation. A disc 101 is placed on the turntable 102 and clamped by a clamper 103 so that the disc 101 is firmly held between the turntable 102 and the clamper 103 in a sandwiched relation. The hub 105 fits into a center hole 106 in the disc 101 with a very small clearance, thereby concentrically positioning the disc 101 with respect to the rotational axis of the motor shaft 104. The disc 101 is rotated by a driving force of a spindle motor 100.
FIG. 21 is a perspective view of a conventional disc 101 on which information is recorded. The disc 101 has a center hole 106 in its center and placed on the turntable 102.
A DVD is a laminated disc which includes two discs bonded together back-to-back. When the two discs are bonded together, they are placed one over the other slightly eccentric due to alignment error. This alignment error varies within a predetermined tolerance and results in a small step in the wall of the center hole of the discs.
When a DVD is loaded onto the aforementioned conventional turntable, the stepped wall of the center hole of the disc may be caught by the hub 105 so that the disc 101 will not descend to the supporting surface of the turntable.
A DVD is usually loaded onto the positioning hub of the turntable so that the hub extends through the center hole with a very small clearance between the DVD. Burrs projecting from the the bonded interface of the disc into the center hole also cause a problem similar to that caused by the stepped wall or may present a problem that the disc is not concentric with the positioning hub. A further problem with the conventional disc is that the bonding agent spreads from between the two discs into the center hole during the manufacture of the disc or during operation of the turntable at elevated temperatures.
SUMMARY OF THE INVENTION
The present invention was made in view of the aforementioned problems.
An object of the invention is to provide a turntable which allows a disc to be smoothly loaded without burrs or a step in the wall of the center hole caught by the positioning hub.
Another object of the invention is to provide a laminated disc which can be loaded onto a turntable without the step and burrs of the wall of the center hole of the disc caught by the hub and can be adjusted to be concentric with the positioning hub upon loading.
Still another object of the invention is to provide a laminated disc which prevents the bonding agent from spreading into the center hole from the bonded interface when the disc is manufactured or operated at elevated temperatures.
A turntable is a table which is mounted to a shaft of a spindle motor and supports a laminated disc thereon so as to drive the disc in rotation. The laminated disc includes a lower disc and an upper disc bonded on the lower disc, and is supported on a disc-supporting surface of the turntable. When the disc is loaded on the turntable, a fitting member of the turntable fits into the center hole of the laminated disc for centering the laminated disc with respect to the shaft. The fitting member fits the center hole of the lower disc when the laminated disc is supported on the disc-supporting surface.
The turntable may include a tapered member in the form of a truncated circular cone which is continuous with the fitting member and guides a laminated disc to the disc-supporting surface. The tapered member has a surface at an angle (θ) with the shaft of the spindle motor. The surface meets three conditions expressed by,
Condition I: tan θ>d1/(m1-m2)
which defines a maximum center-to-center distance d1 between the disc and the shaft;
Condition II: tan θ≧{(n1-n2)/n3}
which defines a lower limit of θ so that the tapered member is prevented from interfering the laminated disc when the laminated disc is loaded onto the turntable; and
Condition III: tan θ<1/μ
which defines an upper limit of the angle (θ) of the tapered member; where
θ is the angle (θ) which the tapered surface of the tapered member makes with the shaft;
d1 is a center-to-center distance between the disc and the shaft;
m1 is a distance between the disc-supporting surface and an upper end of the tapered surface of the tapered member;
m2 is the distance between the disc-supporting surface and a lower end of the tapered surface of the tapered member;
n1 is a center-to-center distance between the upper and lower discs of the laminated disc;
n2 is a clearance between the laminated disc and the fitting member;
n3 is a difference between the distance m2 and a thickness of the lower disc; and
μ is a coefficient of friction between the laminated disc 11 and a surface 15a of the tapered member.
The laminated disc includes lower and upper discs, each having an inner edge which defines the center hole of the disc. The corners of the edges are cut away along the circumference of the center hole. The upper and lower discs are placed together in such a way that the cut-away corners of the upper and lower discs face each other.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a cross-sectional view of a turntable according to a first embodiment when a laminated disc is loaded thereon;
FIG. 2 is a fragmentary cross-sectional view of the turntable and a disc loaded on the turntable, the disc having a burr;
FIG. 3 is a fragmentary cross-sectional view of the turntable and a disc with a bonding agent spreading out of an interface between the two discs;
FIG. 4 illustrates the positional relation between the disc and the turntable;
FIG. 5 is a fragmentary side view of the turntable and the disc loaded to the turntable;
FIG. 6 illustrates the the disc smoothly guided along the inclined surface of the truncated cone;
FIG. 7 illustrates the positioning hub of the turntable having a horizontal surface formed parallel to the disc surface placed on the turntable;
FIG. 8 is a top view of the disc and turntable according to a second embodiment;
FIG. 9 is a cross-sectional view taken along lines J-O and O-K of FIG. 8;
FIG. 10 is an exploded perspective view when the turntable is provided with a ball-chucking construction;
FIG. 11 is a cross-sectional view when the disc is loaded onto the chucking type turntable;
FIG. 12 is a fragmentary cross-sectional side view of a laminated disc according to a third embodiment;
FIG. 13 is a cross-sectional view of the laminated disc when it is loaded to a supporting surface of a conventional turntable;
FIG. 14 is a cross-sectional view of the laminated disc of the third embodiment when it is loaded onto the conventional ball chucking type turntable having a metal chucking ball;
FIG. 15 is a cross-sectional view of a disc according to a fourth embodiment;
FIG. 16 is a top view of the lower disc;
FIG. 17 is a cross-sectional view of another laminated disc;
FIG. 18 is a fragmentary cross-sectional view of a laminated disc with a beveled corner of the center hole and an annular grooved therein;
FIG. 19 is a fragmentary cross-sectional view of a laminated disc having a recess closer to the center hole than the groove of FIG. 18;
FIG. 20 is a cross-section view of a prior art turntable; and
FIG. 21 is a perspective view of a conventional disc on which information is recorded.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will be described in detail with reference to the drawings.
First Embodiment
FIG. 1 is a cross-sectional view of a turntable 10 according to a first embodiment, showing the turntable 10 when a laminated disc 11 is loaded thereon.
Referring to FIG. 1, a positioning hub 5 fits into a center hole 6 in the disc 11 with a very small clearance, for example, several microns, accurately positioning the disc with respect to the rotational axis S-S' of the motor shaft 4. The disc 11 is supported on the turntable 10. A motor shaft 4 of a spindle motor, not shown, is press-fitted into or securely bonded to a truncated cone 15 of the turntable 10 in a similar manner to the prior art turntable shown in FIG. 20. The spindle motor drives the turntable 10 in rotation via the motor shaft 4.
The laminated disc 10 includes two discs placed together, slightly eccentric due to alignment error within a predetermined tolerance. The relative eccentricity of the center holes of the two discs results in a small step 50 in the wall of the center hole 6 of the laminated disc 1. The positioning hub 5 is integrally continuous with the cone 15 having an inclined surface 15a. The inclined surface 15a makes an angle θ with the axis S-S' so that the inclined surface 15a will not interfere with the stepped edge of the wall of the center hole 6.
FIG. 2 is a fragmentary cross-sectional view of a disc 11 which has a burr 12 and is loaded on the turntable 10. FIG. 3 is a fragmentary cross-sectional view of the turntable 10 and the disc 11 when a bonding agent 13 spreads out of an interface 14 between the two discs.
The truncated cone 15 will now be described in more detail with reference to FIGS. 4-7. FIG. 4 illustrates the positional relation between the disc 11 and the turntable 10.
The disc 11 is assumed to have been held above the turntable 10 with its center line D-D' offset a distance d1 from the axis S-S' of the motor shaft 4. Then, the disc 11 is lowered in a direction shown by arrow A, thereby being loaded onto the inclined surface 15a of the turntable 10. The surface 15a of the truncated cone 15 makes an angle of θ with the shaft 4 as shown in FIG. 1. In order that the disc 11 is comfortably loaded onto the turntable 10 without deformation, the disc 11 must first be placed on the inclined surface 15a of the truncated cone 15. This condition is achieved by the following relation.
d2>d1 (1)
where d2 is a dimension of the truncated cone parallel to the disc 11.
The dimension d2 may be expressed as follows:
d2=(m1-m2)tan θ (2)
where m1 is the distance between the disc supporting surface 16 of the turntable 11 and the top flat surface 60 of the truncated cone 15, and m2 is the distance between the supporting surface 16 and the upper end of the positioning hub 5.
From Equations (1) and (2), the following relation is derived.
tan θ≧d1/(m1-m2) (3)
In other words, in order to ensure that d2>d1, it is necessary that the lower limit of the angle θ must satisfy Equation (3).
The distance m1 is selected to be about 2.5 mm since the turntable 11 is usually of thin construction. The distance m2 between the full thickness of the lower disc and the half the full thickness since the disc 11 is placed in position by having the center hole of the lower disc 11b engage the positioning hub 5. A DVD has a thickness of 0.6 mm, and therefore the distance m2 is selected to be 0.3 mm which is a half of the thickness of the lower disc. When manufacturing a DVD, the upper and lower discs are placed together in such a way that the outer diameter of one disc is registered with that of the other. Therefore, the offset d1 of about 0.5 mm usually results from the eccentricity of the outer diameter with respect to the center hole and the dimensional errors of the outer diameters of the upper and lower discs. Consequently, the angle θ greater than 13° is obtained by putting m1=0.5 mm, m2=0.3 mm, and d1=0.5 mm into Equation (3).
FIG. 5 is a fragmentary side view of the turntable 10 and the disc 11 loaded to the turntable 10. The disc 11 has a step 50. There is a small clearance 51 between the lower disc 11b and the positioning hub 5. In order that the disc 11 smoothly fits to the turntable 10 without the truncated cone 15 interfering with the step 50, the lower limit of the angle θ must be determined by the following relation.
tan θ≧{(n1-n2)/n3} (4)
where n1 is the size of the step 50, n2 is the size of the clearance 51, and n3 is the difference between the thickness t and the distance m2. The step 50 or n1 is usually less than 0.1 mm and therefore the distance m2 longer than the half of the thickness t is enough. For DVDs, m2 is 0.3 mm and thickness t is 0.6 mm. The clearance 51 is usually several tens microns and is assumed to be 30 microns in this embodiment. By putting m2=0.3 mm, n1=0.1 mm, n2=30 μm, and t=0.3 mm into Equation (4), the angle θ greater than 13° is obtained.
FIG. 6 illustrates the the disc 11 smoothly guided along the inclined surface 15a of the truncated cone 15. The total weight P of the disc 11 is a force acting downwardly. The weight P is resolved into a component P2 normal to the inclined surface 15a and a component P1 acting downward along the inclined surface 15a. In order for the disc 11 to smoothly slide along the Inclined surface 15a of the truncated cone 15, the following relation must be satisfied.
P1>P3 (5)
where P3 is a friction acting in a direction opposite to the component P1.
The angle θ is determined by putting P1=P cos θ, P2=P sin θ, and P3=μP2=θ P sin θ into Equation (5).
tan θ<1/μ (6)
where μ is a coefficient of friction between the disc 11 and the inclined surface 15a of the truncated cone 15.
Optical discs are usually made of thermoplastic plastics and turntables are made of materials such as thermoplastic plastics or metal. With discs and turntables made of such materials, the coefficient of friction θ is in the range of 0.2-0.5 and is the largest when both the disc and turntable are made of plastics. For μ=0.5, the angle θ is less than 63.5° from Equation (6).
Therefore, the angle θ of the truncated cone 15 should be in the range from 13 to 63.5 degrees, and preferably in the range of 15-60 degrees.
The aforementioned construction offers the same advantages for discs having the burr 12 or the sag 13 of an adhesive on the wall of the center hole of the disc.
In the aforementioned embodiment, the angle θ of the surface of the truncated cone 15 is selected such that the wall defining the center hole 6 of the disc will 11 not touch the inclined surface 15a of the truncated cone 15 if the upper and lower discs of the disc 11 are eccentric with each other within a predetermined tolerance. As shown in FIG. 7, the turntable 10 may be formed with a horizontal surface 17 parallel to the disc surface placed on the turntable 10 so that the truncated cone is continuous with the positioning hub 5 via the horizontal surface 17. The horizontal surface 17 has a radial distance less than about several hundred microns.
Second Embodiment
FIG. 8 is a top view of the disc 11 and turntable 10 according to a second embodiment and FIG. 9 is a cross-sectional view taken along lines J-O and O-K of FIG. 8. Referring to FIGS. 8 and 9, a spring 18 has three spring legs 18a-18b angularly 120° spaced apart and extending outwardly and downwardly. The spring leg has an abutting surface 19 at its free end. The abutting surface 19 is a vertically extending surface. It is to be noted that the abutting surface 19 abuts the circumferential wall of the center hole 6 of the lower disc 11b with a predetermined urging force. This construction is advantageous in that the step 50 or the burr 12 such as shown in FIG. 2 will not touch any part of the turntable 10 and the disc 11 can be positioned in place with no clearance between the abutting surface 19 and the wall defining center hole 6.
FIG. 10 is an exploded perspective view of a chucking type turntable 10a which is provided with a ball-chucking construction. The spring 18 in FIGS. 8-9 is also used in the construction. The chucking construction includes chucking balls 20. FIG. 11 is a cross-sectional view when the disc 11 is loaded onto the chucking type turntable 10a. As is clear from FIGS. 9 and 10, the step 50 in the wall of the center hole 6 of the disc 11 still will not touch the turntable 10a of the chucking construction.
Third Embodiment
FIG. 12 is a cross-sectional view of a laminated disc 11 according to a third embodiment. The upper and lower discs 11a and 11b are beveled at their edges 21 defining the center hole 6, and are placed together so that the beveled edges directly face each other.
FIG. 13 is a cross-sectional view of the laminated disc 11 when it is loaded to a supporting surface 116 of a conventional turntable 102. With the aid of the beveled edges, the turntable 102 can fit into the center hole 6 of the laminated disc 11 without the head corner 52 of the turntable 102 caught by the step 50.
The laminated disc 11 is usually made of plastics by molding and has a thickness larger than 0.5 mm. This thickness is a reasonable thickness that can be achieved with a sufficient dimensional accuracy by molding. Accordingly, the upper and lower discs need to be beveled by a width less than 0.5 mm. For example, the corners of the edges are rounded or radiused by less than R=0.5.
FIG. 14 is a cross-sectional view of the laminated disc 11 of the third embodiment when it is loaded onto the conventional ball chucking type turntable 102 having a metal chucking ball 20. The beveled edge facilitates the smooth passage of the disc 11 over the ball 20 along the turntable 102. The disc 11 can be loaded onto the disc supporting surface 116 of the turntable 102 without being caught by the ball 20.
Fourth Embodiment
FIG. 15 is a cross-sectional view of a disc 11 according to a fourth embodiment. The upper and lower discs 11a and 11b are formed with annular grooves 22a and 22b, respectively, in the bonding surface 14 thereof. The grooves 22a and 22b have a cross section of a semicircle and are close to and concentric with the center hole 6. The upper and lower discs 11a and 11b are placed together so that the grooves 22a and 22b define a toroidal space that acts as a reservoir 22 for holding a bonding agent therein.
FIG. 16 is a top view of the lower disc 11b. The bonding agent 13 is applied to the bonding surface 14 as depicted by hatched portion except an area inner than the annular groove 22b.
When the upper and lower discs 11a and 11b are placed together after applying the bonding agent 13, excessive bonding agent 13 spreads into the reservoir 22, being prevented from further spreading toward the center hole 6. The reservoir 22 also serves to prevent the bonding agent 13 from spreading toward the center hole 6 when the laminated disc 11 is placed in an environment of elevated temperatures.
FIG. 17 is a cross-sectional view of another laminated disc 11. The upper and lower discs 11a and 11b are formed with annular, shallow steps 14a and 14b, respectively, in an area closer to the center hole 6 than the annular groove 22a and 22b. When the upper and lower discs are placed together, the steps 14a and 14b define a space that communicates with the reservoir 22 to accommodate the bonding agent spreading out of the reservoir 22 toward the center hole 6.
The laminated disc may have both a beveled corner of the center hole and an annular grooved therein as shown in FIG. 18. The laminated disc shown in FIG. 18 may further be formed with a shallow recess closer to the center hole than the groove of FIG. 18.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A turntable is a table mounted to a shaft (4) of a spindle motor and the turntable supports a laminated disc thereon and drives the disc in rotation. The laminated disc includes a lower disc and an upper disc stacked on the lower disc, and is supported on a disc-supporting surface. When the disc is loaded on the turntable, a fitting member fits into the center hole of the laminated disc for centering the laminated disc with respect to the shaft. The fitting member fits the center hole of the lower disc when the laminated disc is supported on said disc-supporting surface. The turntable may include a tapered member which guides the laminated disc to the disc-supporting surface. The laminated disc includes lower and upper discs each having an edge which defines the center hole. The corners of the edges are cut away along a circumference of the center hole. The upper and lower discs are placed together so that the cut-away corner directly face each other. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of priority from U.S. Provisional Patent Application No. 61/274,822, filed on 21 Aug. 2009, which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention provides an improved process for the sulfonation of hydroxyaromatics and products made by this process. The described process enables isolation of the sulfonylated hydroxyaromatcs in their free acid forms, which avoids generation of salts as waste products and facilitates recycling of sulfuric acid. The described process also enables sulfonylated hydroxyaromatics to be made from renewable carbon atoms derived from biomass.
BACKGROUND OF THE INVENTION
Tiron™ (trademark of E.I. du Pont de Nemours and Company) is a known chelant. However, it is currently too expensive to make for commercial purposes. For example, in published US 2009/0176684 detergent compositions containing catechols, such as Tiron™ (1,2-dihydroxybenzene-3,5-disulfonic acid), which do not have or do not develop the reddish color associated with the catechol/ferric iron chelate, are disclosed.
Several attempts have been made to prepare Tiron™ or its derivatives but for various reasons, none of these have been commercially practical or cost effective for this purpose. A few of these prior efforts are discussed below.
Some groups have attempted this process using catechol as the starting compound. Cousin, in Compt. Rend. 117, 113 (1893); Bull. Soc. Chim. 11, 103 (1894); and Ann. Chim. 13, 511 (1898), made the free sulfonic acid of Tiron™ using oleum (30%) at 100° C. This process required the use of oleum and elevated temperature. Jakob Pollak and Erich Gebauer-fulnegg, Monatshefte fuer Chemie, 47, 109 (1926) again made the free sulfonic acid of Tiron™ using ClSO 3 H at RT. This process required the use of a chlorinated reagent.
Rhodia in WO 2007/144344 A1, published 21 Dec. 2007, heated a reaction mixture of catechol in H 2 SO 4 to 85-90° C. to form (Tiron™) disodium salt. However, the free acid of 4,5-dihydroxy-1,3-benzenedisulfonic acid (Tiron™) does not precipitate from the sulfuric acid reaction mixture and neutralization is required in order to precipitate the sodium salt of Tiron™. This leads to a substantial salt waste stream and complicates the task of recycling the H 2 SO 4 .
A compound similar to Tiron™, namely a 2,3,4-trihydroxybenzenesulfonic acid, has been made starting with 1,2,3-trihydroxybenzene, which is also known as pyrogallol (PG). The process by Schieff, Ann. 178, 187 (1875) used H 2 S 2 O 7 at 100° C. This process required the use of pyrosulfuric acid and elevated temperature. Two groups, Delage, Compt. Rend. 131, 450 (1900); 133, 298 (1901); 136, 760, 893, 1202 (1903) and Anschutz, Ann. 415, 87 (1918), tried this process using H 2 SO 4 at 100° C. These processes required elevated temperature and produced a mixture of products.
Two groups, Delage, Compt. Rend. 132, 421 (1901); and Pollak, Gebauer-fulnegg, and Litvay, Monatshefte fuer Chemie, 47, 537 (1927), used PG as the starting material to make 4,5,6-trihydroxy-1,3-benzenedisulfonic acid, using H 2 SO 4 at 100° C. This process required elevated temperature.
Clearly, it would be advantageous to have a cost effective and practical approach using renewable biomass resources to make such additives.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a novel process using renewable carbon atoms derived from biomass containing detectable 14 C content determined according to ASTM D6866-08 and preferably containing a 14 C content up to 0.0000000001% (one part per trillion) to make sulfonated hydroxyaromatic compounds. Specifically, this invention provides a process for preparing a sulfonylated hydroxyaromatic compound of the formula:
wherein: X is H or Na; R 1 is SO 3 H, SO 3 Na, CO 2 H, or CO 2 Na; and R 2 is H or OH; which comprises reacting a compound derived from renewable carbon sources containing up to 1 part per trillion of 14 C of the formula:
wherein: R 1 is H or CO 2 H; and R 2 is H or OH; with concentrated sulfuric acid at a temperature from room temperature (RT) to about 120° C. and, optionally under a N 2 atmosphere; and with separation of the product based on precipitation of the free acid of the sulfonylated hydroxyaromatic, optionally in the presence of a solvent. The compounds of Formula I having renewable carbon atoms derived from biomass containing detectable 14 C content determined according to ASTM D6866-08 and preferably containing a 14 C content up to 0.0000000001% (one part per trillion) are also novel.
DETAILED DESCRIPTION OF THE INVENTION
It is understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in this specification, the singular forms “a”, “an”, and “the” include plural referents unless the content clearly indicates otherwise.
Also, certain US patents and PCT published applications have been incorporated by reference. However, the text of such patents is only incorporated by reference to the extent that no conflict exists between such text and other statements set forth herein. In the event of such conflict, then any such conflicting text in such incorporated by reference US patent or PCT application is specifically not so incorporated in this patent.
Glossary
The following terms as used in this application are to be defined as stated below and for these terms, the singular includes the plural.
biomass refers to the carbon atoms in the form of cellulose, lignocellulose, and hemicellulose and starch contained in nonfood and food plants such as corn, sweet sorghum and sugar cane and their waste which cannot be used as a food source which can be broken down to simple sugars which can be converted into the compounds of Formula II; such compounds containing detectable 14 C content determined according to ASTM D6866-08 and preferably contain a 14 C content up to 0.0000000001% (one part per trillion)
catechol means 1,2-dihydroxybenzene
conc. means concentrated; for sulfuric acid means from about 50% to about 99%, preferably ˜98% as purchased from Sigma Aldrich g means grams hr(s). means hour(s) L means liter min(s) means minute(s) mL means milliter PCA means protocatechuic acid or 3,4-dihydroxybenzoic acid PG means pyrogallol or 1,2,3-trihydroxybenzene RBF means round bottom flask RT means ambient temperature or room temperature, from about 20 to about 25° C. SPCA means sulfonated protocatechuic acid or 3,4-dihydroxy-5-sulfobenzoic acid Tiron™ means sulfonated catechol or 1,2-dihydroxy-3,5-benzenedisulfonate sodium salt
General Remarks
Because sulfonylated hydroxyaromatics are desired compounds to make several useful additives for example such as determining metal ion concentrations, serving as chelants and removing unwanted coloration in fabric care, many processes have been tried over the years to use various starting compounds to obtain them.
Many processes have started with catechol, but this compound has proven expensive as the source varies with supply and generally is either in short supply and/or high priced. Thus as a commercial resource it has not proven a good starting compound. For sustainability considerations and reduction of carbon footprints, there is also a desire to use starting materials derived from renewable feedstocks in the synthesis and manufacture of sulfonylated hydroxyaromatics.
Another starting compound used is pyrogallol (PG) but the reactions usually have a low yield, lead to product mixtures, or make an alkali metal salt product which can lead to undesirable salt waste streams or complicates recycling of the sulfonylation reagent. The process often requires high temperatures for a significant time, which adds to the cost of the final product.
In contrast to the known processes, the present invention provides a renewable starting material from biomass, using a process that can be run at RT or elevated temperature and high yield. Also with recyclization of the conc. sulfuric acid and lower waste stream issues this process is more environmentally acceptable. The following flow chart illustrates the present process in general terms.
In Formula II, the starting compound has R 1 is H or CO 2 H; and R 2 is H or OH. When R 1 and R 2 are both H, then the compound is catechol; when R 1 is H and R 2 is OH, then the starting compound is pyrogallol; and when R 1 is CO 2 H and R 2 is H, then the starting compound is protocatechuic acid. Because biomass is a starting source to make these compounds of Formula II, these compounds contain detectable 14 C up to a 14 C content of 0.0000000001% (one part per trillion). The sulfonation reaction uses conc. H 2 SO 4 , which can be recycled.
In Formula I, the product has R 1 is SO 3 H or CO 2 H and R 2 is H or OH. When R 1 is SO 3 H and R 2 is H, then the product is Tiron™. When R 1 is SO 3 H and R 2 is OH, then the product is 4,5,6-trihydroxy-1,3-benzenesulfonic acid. When R 1 is CO 2 Na and R 2 is H, then the product is 3,4-dihydroxy-5-sulfobenzoic acid also referred to as sulfonated protocatechuic acid (SPCA). Each of these compounds will contain detectable 14 C content up to a 14 C content of 0.0000000001% (one part per trillion) from the compounds of Formula II.
For the above general process of this invention the reaction conditions are: 1) use of concentrate sulfuric acid; 2) temperatures from RT to about 120° C.; 3) preferably under a N 2 atmosphere; and 4) time is not critical but should be for a time sufficient to allow the desired sulfonation to occur. Unlike prior processes no fuming sulfuric acid is used and the free acid of the sulfonylated hydroxyaromatic is isolated from the reaction mixture. The free acid usually precipitates easily and thereby reduces the waste stream issues while allowing the sulfuric acid to be recycled. Optionally, if needed to aid in separation of the compounds of Formula I an additional solvent can be present. Sulfonylation is possible from RT through elevated temperatures.
When catechol is used as the starting compound it has been found that concentrated sulfuric acid is the preferred sulfonation agent followed by neutralization with base such as sodium hydroxide. This synthetic route avoids the use of oleum or fuming sulfuric acid. However, neutralization of the sulfonylation reaction mixture is required in order to separate the sulfonylated hydroxyaromatic as its sodium salt.
If the starting compound is pyrogallol (PG), then the present process uses concentrated sulfuric acid as the preferred sulfonation agent. The sulfuric acid can be recycled.
One starting compound is protocatechuic acid (PCA), which is obtained from biomass by fermentation. No process for commercial production of PCA has been available previously in sufficient scale. Now PCA is obtained from microbial synthesis from glucose as the starting material derived from renewable starch or cellulose feedstocks [see W. Li et al., J. Am. Chem. Soc. 127 (9), 2874-2882 (2005); and Frost et al. U.S. Pat. No. 5,616,496, U.S. Pat. No. 5,629,181, and U.S. Pat. No. 5,487,987, each incorporated herein by reference]. The product obtained is SPCA, which precipitates from the reaction solution as the free acid. No neutralization is required and the product is free of alkali metal salts.
The compounds of Formula I have utility as chelants that can be used in a variety of ways, including but not limited to determining metal ion concentrations, serving as chelants and removing unwanted coloration in fabric care.
This invention will be further clarified by a consideration of the following examples, which are intended to be purely exemplary of the present invention. The lettered Examples are comparative. The numbered Examples are of this invention.
EXAMPLES
Example A
Procedure from WO 2007/144344 A1 by Rhodia
Into a 1 L flask containing 682 g of sulfuric acid was added 150 g of catechol at RT. The reaction mixture was heated to 85-90° C. for 5 h for the sulfonation process to occur. When the reaction mixture has cooled down to 50° C., 231.9 g of 47% NaOH solution was added to the reaction mixture and 1,2-dihydroxy-3,5-benzenedisulfonate sodium salt precipitated. The reaction mixture was cooled down to 15-25° C. and the solid was filtered through a Büchner funnel. The solid was washed (3×) with 115 g of isopropanol and dried under vacuum at 60° C. to provide 290 g of Tiron™ as an off-white solid in a yield of 68%. Thus this process requires neutralization with base and forms the salt.
Example B
Sulfonation of pyrogallol (PG) with H 2 SO 4 at 90° C. for 5 h
Into a RBF containing PG (10 g, 79.3 mmol), sulfuric acid (38.9 g, 396 mmol) was added. The mixture was heated at 90° C. in an oil bath for 5 h. The reaction was allowed to cool to 50° C. and aqueous NaOH (6.36 g in 20 mL water) was added dropwise to the reaction mixture and the resulting precipitate was obtained by filtration.
The 1 H NMR of the isolated solid has only one peak at 7.1 ppm; however, no carbon was detected by 13 C NMR, suggesting that the isolated solid might be of some inorganic salt. Thus this process as disclosed by Rhodia in the patent WO 2007/144344 A1 is not applicable for production of the desired 4,5,6-trihydroxy-1,3-benzenedisulfonic acid for further use.
Present invention using catechol derived from biomass as the starting compound.
Example 1
Sulfonation of Catechol in Concentrated H 2 SO 4
The sulfonation of catechol derived from biomass using concentrated sulfuric acid was followed as described in Example A with minor modifications.
Into a 1 L RBF containing 682 g of concentrated (98%) sulfuric acid, was added 150 g of catechol at RT. The mixture was heated at 95° C. for 5 h. When the reaction mixture was cooled to 50° C., 232 g of 47% (by weight) NaOH solution in water was added dropwise via an addition funnel to the reaction mixture to precipitate 1,2-dihydroxy-3,5-benzenedisulfonate sodium salt. Upon complete addition of NaOH solution, the reaction was cooled to 15-25° C. and the precipitate was filtered through a Büichner funnel. The solid was washed with isopropanol (600 mL) and dried under vacuum at 60° C. to yield 312 g (73% yield) of 1,2-dihydroxy-3,5-benzenedisulfonate sodium salt as an off-white solid.
Present invention using pyrogallol (PG) derived from biomass as the starting material.
Example 2
Sulfonation of pyrogallol (PG) with concentrated H 2 SO 4 at RT
Into a round bottom flask containing PG (10 g, 79.3 mmol), sulfuric acid (38.9 g, 396 mmol) was added at room temperature under nitrogen atmosphere. With stirring, the mixture was allowed to react at RT for 24 h. 100 mL of acetonitrile was then added to the reaction flask and the resulting white precipitate was obtained by filtration. The white solid was washed with pentane (2×) and dried under reduced pressure to provide 3.6 g of 4,5,6-trihydroxy-1,3-benzenedisulfonic acid. The acetonitrile filtrate was cooled to 0° C. in an ice-water bath and this induced more precipitation that was filtered and dried to yield another 4.8 g of 4,5,6-trihydroxy-1,3-benzenedisulfonic acid in an overall yield of 37%.
1 H and 13 C NMR analysis of the isolated free acid pyrogallol disulfonate formed from sulfonylation of pyrogallol are as follows:
1 H NMR (300 MHz, DMSO- d6 ): ppm 7.1 (s).
13 C NMR (75 MHz, DMSO- d6 ): ppm 115.6, 122.1, 132.5, 144.0.
Process of this invention using PCA derived from biomass as the starting compound to make SPAC.
Example 3
Sulfonation of Protocatechuic acid (PCA) with H 2 SO 4 at 120° C.
PCA (10 g, 65 mmol) was mixed with concentrated sulfuric acid (39 g, 398 mmol). The mixture was heated at 120° C. for 8 h. The reaction mixture was diluted with 100 mL acetonitrile resulting in the formation of a white precipitate, which was filtered, washed with excess acetonitrile, and dried under reduced pressure to yield 12.2 g (80% yield) of the free diacid of 3,4-dihydroxy-5-sulfobenzoic acid (SPCA).
The 1 H and 13 C NMRs of the isolated product confirmed its structure and its spectra are as follows:
1 H NMR (300 MHz, DMSO- d6 ): ppm 7.2 (m, 1H), 7.5 (m, 1H).
13 C NMR (75 MHz, DMSO- d6 ): ppm 117.0, 119.9, 120.7, 130.8, 145.7, 146.6, 167.1.
Elemental analysis for C 7 H 6 O 7 S: C, 35.90; H, 2.58. Found: C, 35.59; H, 2.62.
Although the invention has been described with reference to its preferred embodiments, those of ordinary skill in the art may, upon reading and understanding this disclosure, appreciate changes and modifications which may be made which do not depart from the scope and spirit of the invention as described above or claimed hereafter. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. | The present invention provides improved process for the sulfonation of hydroxyaromatics amenable to direct isolation of the sulfonylated hydroxyaromatics in their free-acid forms. The process allows for the recyclization of sulfuric acid and minimizes waste. The starting materials are from a renewal resource, e.g., biomass, and contain detectable 14 C up to a 14 C content of 0.0000000001% (one part per trillion). The products made include sulfonated catechol, disulfonated pyrogallol and sulfonated protocatechuic acid. | 2 |
[0001] This nonprovisional is a divisional application of U.S. application Ser. No. 12/625,032, which is a continuation of International Application No. PCT/DE2008/000663, which was filed on Apr. 15, 2008, and which claims priority to German Patent Application No. 10 2007 024 350.4, which was filed in Germany on May 24, 2007, and which are both herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a method and a device for operating a drawing line or drawing unit.
[0004] 2. Description of the Background Art
[0005] DE 21 48 619, which is incorporated herein by reference, illustrates a device for drawing of tows having high polymer synthetic filaments in drawing units with intake units and drawing units where the tow mass is divided into several individual tows.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a method and a device for driving a drawing unit in line.
[0007] In an embodiment, each drawing roller can be driven by a separate drive unit that can be controlled by an actuator to operate at a specified speed or with the torque required for driving the relevant drawing roller. Different speeds (rotational speeds) of two drawing units allow the tows or filaments passing round the drawing rollers to be drawn by a certain amount. The accumulated speed ratio from the first intake drawing roller to the last discharge drawing roller can range, for example, from 1:3 to 1:4. Since the individual drawing rollers or godets are not driven centrally by one drive unit, but each godet instead is driven individually, the drawing unit can be operated more precisely. It is also an advantage that the drives within one drawing unit are nearly identical and that the load can be distributed evenly. Slip can be considerably reduced by the individual drives.
[0008] In an embodiment, the required torque of the drive unit can be set or the drives of the individual godets can be operated through a control unit.
[0009] In another embodiment, the motors can be designed as asynchronous drives and the control unit can contain a frequency converter including a tacho-generator connectable to the motor. The frequency converter can be used to set the required rotational speed and thus also the torque of one godet each. The frequency converter allows the required optimum speed to be adjusted for each individual motor. For more complex control requirements, field-oriented converters can be used. These can include a speed controller based on a secondary current controller. The motor characteristics are saved or possibly even automatically determined and adapted in an electronic motor model stored in the converter. This offers the advantage that there has to be no separate speed measurement and feedback for controlling speed and torque. The only feedback used for control is the instantaneous current. Based on current level and phase relation to voltage, all required motor conditions (speed, slip, torque and even heat loss) can be established.
[0010] If a disturbance occurs, such as tow rupture during drawing, this disturbance is also registered by a speed sensor and/or by means of the frequency converter, a fault signal is generated and the line can immediately be switched off automatically. For this purpose, the speed and/or the torque of each motor is registered and compared to a given value which can exclusively occur in the event of fault (sudden speed increase). These values are established and saved. By specific adjustment of speeds the respective motors can be designed in an optimum manner, the motor rating can be fully used and costs can consequently be reduced. Moreover, the range of applications of such a line will expand and frequent malfunctions will be avoided.
[0011] It is also an advantage that the frequency converter assigned to a motor compares the actual torque with the setpoint torque and then adapts the drive speed of the appertaining motor.
[0012] It is beneficial that the surfaces of the godets are chromium-plated or provided with ceramic coating in order to generate higher adhesion.
[0013] In an embodiment, the first godet can be driven at a fixed speed which is not changed by the open-loop or closed-loop control system; the speed of the last godet is also fixed, thus determining the drawing ratio. The line is started according to the dotted line ( FIG. 7 ) with a freely selectable starting draw ratio, while the speed increase is distributed among the individual godets either in a linear or freely selectable manner. The tow can be placed on the godets and speed optimization is started. The drives of the individual godets are constantly monitored by means of frequency converters and the actual torque is compared with the calculated average setpoint torque, the speed is thus controlled accordingly while the line is accelerated to maximum speed. Also, the speeds can be saved in a setpoint curve and can be used during the next starting procedure to quicken the starting cycle.
[0014] It is also an advantage that optimum drive adjustment of all motors or setting of the desired driving torque for each motor is done automatically through gradual approximation or iteration toward a setpoint torque curve or setpoint torque characteristic.
[0015] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
[0017] FIG. 1 is a schematic representation of a drawing line with two drawing units;
[0018] FIG. 2 is a top view of the drawing line with two drawing units and one joint drive each;
[0019] FIG. 3 is a schematic representation as a top view of an individual motor arrangement for individually and separately driving the godets of a drawing unit;
[0020] FIG. 4 is a process speed diagram of the godets in a drawing line with two drawing units according to FIG. 2 ;
[0021] FIG. 5 is a torque diagram of the individual godets of the drawing line according to FIG. 2 ;
[0022] FIG. 6 is a torque diagram of the individual godets in a drawing line with two drawing units according to FIG. 2 with a second speed or drawing profile;
[0023] FIG. 7 is a diagram with rising speed curve for adapted torques of a godet arrangement in line with FIG. 3 ; and
[0024] FIG. 8 is a torque diagram for the individual godets of an adjusted machine in line with FIG. 3 .
DETAILED DESCRIPTION
[0025] FIG. 1 shows a layout of a drawing line 1 known as such with drawing rollers or godets 2 which are arranged in two drawing units 1 . 1 , 1 . 2 . The two drawing units 1 . 1 and 1 . 2 contain arrangements of seven godets 2 each. In a drawing line 1 to the state of the art, as illustrated in FIG. 2 , the godets 2 of drawing units 1 . 1 and 1 . 2 are driven by a central driving unit or through one assigned motor 3 . 1 , 3 . 2 each and a gearbox symbolized in the respective frame 4 . 1 , 4 . 2 .
[0026] FIG. 3 shows the drawing line 1 according to the invention with a total of fourteen godets 2 . The drawing line 1 according to this embodiment includes a first drawing unit 1 . 1 and a second drawing unit 1 . 2 .
[0027] According to FIG. 3 , individual motors 31 . 1 , 31 . 2 , . . . 32 . 14 are mounted in the drawing units 1 . 1 , 1 . 2 in one support 5 . 1 , 5 . 2 each, which also contain the bearings for rotation of the godets 2 . The supports 5 . 1 , 5 . 2 are shown only schematically. The sheet with FIG. 3 and the sheet with FIG. 2 both show the overall layout of drawing line 1 as FIG. 1 so that the assignment of drives 31 . 1 , 31 . 2 , . . . 32 . 14 to the fourteen godets in all of the two drawing units 1 . 1 , 1 . 2 becomes clear.
[0028] Each motor 31 . 1 , 31 . 2 , . . . 32 . 14 , which can be designed as a water-cooled motor, is used for direct drive of an individual godet 2 . Inserted between the drive shaft of the motor 3 and the drive shaft of the godet 2 is a joint, a joint shaft or a self-aligning bearing so that lateral offset or effects caused by bending moments can be compensated.
[0029] FIG. 4 shows a speed diagram with two different speeds V of a first and second drawing unit 1 . 1 and 1 . 2 driven by one motor 3 . 1 and 3 . 2 each, where V 1 is the speed (circumferential speed =rotational speed of godet times radius of godet surface; the circumferential speed corresponds to the speed of the tow 6 ; this description always talks of speed while the value of rotational godet speed results from the above relationship) of the godets 2 of the first drawing unit 1 . 1 and V 2 is the speed of the godets 2 of the second drawing unit 1 . 2 (see also FIG. 1 and FIG. 2 ). The continuous line shows a higher drawing ratio, the dashed line a lower one. The course of the torques M exerted on the godets 2 by the tow 6 (starting from an average torque) is illustrated in the diagrams of FIGS. 5 and 6 . The bars shown in continuous outlines in FIG. 5 correspond to a higher drawing ratio and the bars shown in dashed outlines in FIG. 6 to a lower one—see also the speeds represented as continuous and dashed lines in FIG. 4 .
[0030] FIG. 4 makes it clear that the first drawing unit 1 . 1 is driven more slowly than the second drawing unit 1 . 2 so that the tows 6 schematically illustrated in FIG. 1 are drawn. As a result, the total torque taken up by the second drawing unit 1 . 2 is higher than the torque taken up by the first drawing unit 1 . 1 . The difference in torques between the first and second drawing units 1 . 1 and 1 . 2 represents the frictional heat or drawing force, respectively, which is required for drawing the tow or filaments 6 . Drawing the molecules of a filament requires a certain drawing force. By drawing the molecule of a filament a certain friction is generated between the individual molecules so that the filaments or the tow can heat up to about 100° C.
[0031] FIG. 5 shows the distribution of torques M among the altogether fourteen godets 2 in the two drawing units 1 . 1 , 1 . 2 (see FIG. 4 —continuous line). FIG. 6 shows the distribution of torques for a smaller drawing ratio (FIG. 4 —dashed line). The maximum and minimum torques are identified by M 1mx , M 2max , M 2min etc.
[0032] As suggested in FIG. 1 , the last drive roller of the last godet 2 in the first drawing unit 1 . 1 and the first drive roller of the first godet 2 in the second drawing unit 1 . 2 are wrapped by the tow 6 only by 90° so that at these points not the full torque is transferred. As a result a higher slip occurs at these points. Since the tow 6 can slide over the surface of the godet 2 at these points, the godet is more strongly worn at and does not transfer the full torque either. The drawing forces on the last godet 2 of the first drawing unit 1 . 1 and on the first godet 2 of the second drawing unit 1 . 2 mostly are therefore somewhat lower than those on the neighboring godets 2 . It is an advantage here that the surfaces of these godets are chromium-plated or have a ceramic coating in order to produce better adhesion.
[0033] When calculating the driving force based on the example of FIGS. 1 and 2 (state of the art), the selection of a drive motor is determined by the maximum torque M 2max ( FIG. 5 or FIG. 6 ), i.e. the driving unit is oversized. Consequently, larger gears are required so that modifications of customary lines according to FIG. 1 are costly and time-consuming.
[0034] With a driving unit according to FIG. 3 , the energy consumption can be reduced. Here the drives are laid out individually for the maximum demand of the respective godets 2 by grading the specific drive speeds and thus make available for each individual godet 2 a specific ideal driving torque. A total torque M d =M/N must be made available for this purpose, M d being the average torque, M the motor torque and N the number of drive for driving a single godet 2 .
[0035] The individual motors 31 . 1 .- 32 . 14 are designed for the specific maximum torque of a godet 2 . With the use of a frequency converter, the required speeds V 1 and V 2 can be monitored and adjusted in such a way that the desired drawing effect is achieved for the tow 6 . For this purpose, a torque control system is used for driving all motors 31 . 1 - 32 . 14 . The previously established M d is the setpoint torque for driving all motors. See also FIGS. 7 and 8 .
[0036] V 1 is the initial speed which is gradually increased according to the desired drawing effect on the tow 6 to the subsequent values according to FIG. 7 so that the desired drawing effect is achieved. If the actual torque differs from the setpoint torque, the current speed is adapted to the setpoint speed by iteration using the control system.
[0037] As shown by FIG. 7 , the tow 6 can be easily drawn at the beginning as it still can be strongly elongated. The more the tow 6 has been elongated, the higher the required torque for driving the respective motor 3 , as the drawing forces increase with increasing elongation. The speed increments for godets one to seven are much higher than the speed increments of the subsequent godets.
[0038] The torques of the godets 2 are sampled several times per time unit so that the drive speed of the individual godets 2 can be adapted. The signal sampled by the control system represents the controlled variable used to determine the required drive speed and thus to determine the required torque of the godets 2 .
[0039] By continually monitoring the torque and adjusting the required torque, the drive system after a short run-in time is continuously optimized for the required conditions. As a consequence, only the amount of drive energy required for driving each individual motor 3 is made available. Oversizing of the drive unit can be avoided by the control system in line with the invention using the control curve according to FIG. 7 .
[0040] The drive of a drawing line during the optimization stage is effected by the following process steps:
[0041] a) The first godet 2 (FIGS. 7 —N=1) is driven at a pre-determined speed V 1 (which is not changed by the control system, thus remains constant and is selected to match the speed, for example, at which the tow 6 arriving from the spinning plant is supplied). Another given speed is the operating speed V 2 of the last godet (according to FIG. 3 —driven by motor 32 . 14 ). This determines the drawing ratio. This ratio also depends on how the drawn tow 6 shall be further processed.
[0042] b) The line is started according to the dashed line ( FIG. 7 ) with a freely selectable starting draw ratio with the speed increase being distributed either in a linear manner (or freely selectable) among the individual godets. This means that the godets (FIGS. 7 —N=2, 3, 4 . . . . ) following the first godet (FIG. 7 —left end, N=1) are driven at a speed increased in a linear manner (or by a freely selectable function). This means that the initial speed distribution is determined, which is identified by K A in FIG. 7 . The speed of the last godet (FIGS. 7 —N=14) is preferably smaller than the intended final speed V 2 . In FIG. 7 , V A is the speed of the initial drawing stage, so that in this case V A <V E .
[0043] c) The tow 6 is placed on the godets and the torque optimization process is started.
[0044] d) The drives 31 . 1 , 31 . 2 . . . 32 . 14 of the individual godets 2 are continually monitored by means of the control system and the actual torques compared to the specified setpoint torques. The speeds of the individual godets are controlled accordingly. Based on an initial speed distribution (FIG. 7 —curve K A ), the drives 31 . 2 . . . 32 . 14 of the godets are accelerated—resulting during the individual iterations in the speed distributions suggested by the dashed lines above the starting curve K A in FIG. 7 . This optimization process continues until the torques of the individual drives 31 . 1 , 31 . 2 . . . 32 . 14 meet the specified setpoints and the torque of the last godet (FIGS. 7 —N=14) reaches the specified final speed V 2 which defines the draw ratio. The torques of the individual drives 31 . 1 , 31 . 2 . . . 32 . 14 are preferably controlled until the situation represented in FIG. 8 is given, namely that the same torque is given throughout.
[0045] e) The speeds of the godets of the final curve K E thus obtained are saved and can be used as setpoint values during the next starting procedure to accelerate the start-up process.
[0046] As mentioned above, it is possible to drive the last godet (N=14) right from the beginning at the speed V 2 (required speed) defining the draw ratio (V A =V E ). Preferably, however, the starting torque is selected according to the formula V A <V E so that unfavorable situations during the optimization stage can absolutely be avoided.
[0047] Speed changes (V 1 and/or V 2 ) during operation of the drawing line in conformity with the invention are carried out analogously. Here also the speeds of the individual godets are optimized in such a way that the specified setpoint torques are reached.
[0048] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims. | A method and device for operating a drawing line or drawing unit for drawing cables from polymer threads using a plurality of driven drawing rollers. According to the invention, each drawing roller is controlled to a prescribed motion value. To this end, each drawing roller is associated with a separately controllable drive device. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to acceleration enrichment for petrol injection systems.
Petrol consists of chains of hydrocarbons of varying length. As temperature increases and pressure decreases, even the longer molecule chains vaporize.
during idling conditions in petrol injection systems, a vacuum is present in the inlet manifold downstream of the throttle valve. The injected petrol vaporize completely and passes into the cylinder. However, as the throttle valve is opened, the intake mainfold pressure increases correspondingly. The tendency of the fuel to vaporize then decreases, the result being that longer fuel molecule chains are deposited in liquid form as a film on the wall of the intake manifold. The latter quantity of fuel is not combusted and the mixture which is actually combusted is too lean. The acceptance of petrol is thus poor during acceleration conditions. It is the object of acceleration enrichment (BA) to provide an excess quantity of fuel during acceleration so that the engine receives the correct mixture composition during acceleration despite the formation of the film on the wall.
This excess quantity is determined during initial installation of new engines and is stored permanently in the data store of the control device of the fuel injection system.
It has recently been established, however, that coking of the inlet valves occurs following a longish operating time and dependent upon the type of petrol used and the driver's driving technique. This has a deleterious effect on acceleration, since the coking on the intake valve acts during acceleration as a sponge in addition to the film on the wall. Fuel drops are caught in the coked, porous surface of the intake valve and are not combusted. As a consequence of the resulting too-lean mixture, the engine torque drops considerably. In the worst cases, the engine can actually stop during an acceleration demand. If the acceleration enrichment quantity is increased considerably, normal driving is once again possible. However, this excess quantity cannot be provided for in a new engine, since it would not then be possible to adhere to legal exhaust-gas limitations. Also, the driving performance of new vehicles would be poorer, because over-enrichment would cause the engine torque to drop during acceleration. A method is therefore required which automatically adapts the excess acceleration quantity to engine conditions.
Some adaptive methods for acceleration enrichment are already known, e.g. as described in DE-OS 2 841 268 (GB-PS No. 20 30 730) and US-PS No. 4 245 312.
However, these known methods use only the information from a conventional lambda (air-fuel ratio λ) regulator for the adaptation. Conventional lambda regulators are, however, only activated at engine temperatures of above 20° C. Below this temperature, there is controlled driving only, because an engine requires a richer mixture than lambda=1. In addition, there are no legal exhaust-gas regulations effective below this temperature. The only criterion in this range is the driving performance. Up till now, the only technique available has been to apply to cold engines adaption values established for a warm engine, without the accuracy thereof being tested.
It has now been determined using some actual examples of coked intake valves that the acceleration enrichment factor for a warm engine must be increased some five-fold with respect to the new state in order for lambda=1 to be obtained again during acceleration enrichment. In the known methods, in the case of a cold engine (-30 degrees . . . +20 degrees), the acceleration enrichment, which has been considerably increased over that for a warm engine, is increased by a further factor of 0.5 during engine warm-up. There is thus a risk of over-enrichment.
It is an object of the present invention to provide a technique of adaptive acceleration enrichment which overcomes the above-discussed problems of the known solutions.
SUMMARY OF THE INVENTION
The present invention is a system and method for adaptive acceleration enrichment for fuel injected engines in situations when there is active and inactive lambda regulator control.
The system and method of the present invention are used during acceleration enrichment periods to ideally achieve lambda=1 operation of the engine. This is accomplished by developing and applying acceleration enrichment whether the engine is warm or cold.
According to the method of the present invention, the fuel injection quantity t1 is determined for a given acceleration enrichment period. From this determination, the adaptive factor for acceleration enrichment is determined based on whether or not there is active or inactive lambda regulator control.
If there is active regulator control, the adaptive factor is based on the lambda regulator value Fr being compared with the average regulator value Frm (which is an average of Fr values from previous acceleration enrichment periods). The adaptive factor then cause adjustment of the fuel injected to compensate for the injected mixture being too rich or too lean during acceleration.
When there is inactive lambda regulator control, there are no Fr values available for use in determining the adaptive factor. So, a lambda probe is used along with the presence or absence or engine speed drops during the previous enrichment periods to provide a basis for determining the adaptive factor.
This has the advantage that adaptive acceleration enrichment can be maintained satisfactorily even during the warming-up phase of the engine.
BRIEF DESCRIPTION OF THE DRAWING
The invention is described further hereinafter, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a flow diagram illustrating the overall operation of a system in accordance with the present invention;
FIG. 2 is a flow diagram illustrating the overall operation of the system when providing adaptive acceleration enrichment without active lambda control;
FIG. 3 is a flow diagram showing greater detail of the operation without active lambda control; and
FIG. 4 is a flow diagram illustrating the operation of the system when providing adaptive acceleration enrichment with active lambda control.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
When calculating the quantity of fuel to be injected during acceleration enrichment under normal operational (engine warm) conditions, an engine load single t1, which is proportional to the mass of intake air per stroke, is used to form a control time ti of an injection valve, in that the engine load signal is multiplied by other correction factors Fi and then added to a voltage correction time TVUB.
Ti=tL×Fi+TVUB
The factors Fi include a factor Fr, by way of which the lambda regulator acts on the mixture, as well as an acceleration factor Fba. Thus:
Fi=Fr×Fba(t)×Fue, Fue=other factors,
which need not be considered for the present purposes.
At the moment at which acceleration enrichment is triggered, the acceleration factor Fba(t) is raised to an initial value Fba(O) and is subsequently linearly controlled downwards with the time constants DTBAM to the value 1. Thus:
FBA(t)=FBA(O)-DTBAM×1
The initial value FBA(O) is made up of the following:
FAB(O)=1+FBAQ×FBAM×KFBA×FBAAM,
where
FBAQ--factor dependent on the gradient of the load signal
FBAM--factor dependent on engine temperature
KFBA--performance graph factor dependent on load and speed
FBAAM--adaptation characteristic dependent on engine temperature.
The characteristic curve for FBAAM consists of support points at which values are stored and between which linear interpolations are made.
e.g. FBAAM=f(TMOT), TMOT-engine temperature
There may, for example, be two support points:
Support point 1=a value FBAA1 associated with TMOT1
Support point 2=a value FBAA2 associated with TMOT2
The characteristic value of FBAAM for an engine temperature of between TMOT1 and TMOT2 is thus
FBAAM(TMOT)=FBAA1+
(FBAA2-FBAA1)×(TMOT-TMOT1)/(TMOT2-TMOT1).
For active lambda control conditions, (i.e. when the engine is warmed up) the criterion for adaptation is obtained from the lambda regulator output.
However, the lambda signal arrives too late to correct an acceleration operation which is still running. This is conditioned by the time the exhaust gas takes to reach the lambda probe in the exhaust manifold and by the response delay of the probe itself.
The probe supplies only the statement:λmixture too rich (λ<1) or too lean λ>(1). Only at the instant at which the probe voltage changes (i.e. There is a voltage jump) is it known that the exhaust gas flowing past is at lambda=1.
The integrating behavior of the lambda regulator does, however, make it possible to conclude to what extent the mixture was incorrect on gas admission. The longer and more intensely the regulator has to enrich the mixture in a ramp-like manner following acceleration enrichment until the problem once again indicates a rich mixture, the leaner the mixture will be during acceleration.
Adaptive acceleration enrichment with active lambda regulation uses the following correlations:
An average value Frm is formed from the values at the control output Fr at the instants of probe jump.
When an acceleration enrichment operation is triggered, a time counter having the value TBA is started. Only when the counter has stopped is the next probe transient sought. In this way, it is ensured that no problem signal is used for evaluating the acceleration enrichment which belongs to the mixture prior to the acceleration enrichment.
The value of the lambda regulator output Fr at the instant of the probe jump is compared with the stored average value Frm obtained previously. The leaner the mixture during acceleration enrichment, the longer and further the lambda governor had to enrich the mixture in a ramp-like manner until the problem once again detected a mixture where lambda=1,
If the difference between Fr and Frm lies above a threshold DFRP, then the above-described adaptive characteristic FBAAM, which is stored as a function over engine temperature is adjusted, and, for example, has two support points according to the following formula:
FBAA1(TMOT1)-new=FBAA1(TMOT1)-old+(FR-Frm)×ZBAA×(TMOT-TMOT1)/(TMOT2-TMOT1)
and
FBAA2(TMOT2)-new=FBAA2(TMOT2)-old+(Fr-FRm)×ZBAA×(TMOT2-TMOT)/(TMOT2-TMOT1)
The learning speed of the adaptation is adjusted by way of the value ZBAA.
If the difference is negative and exceeds another threshold DFRN, then the adaptation factor is reduced in accordance with the following formula:
FBAA1(TMOT1)-new=FBAA1(TMOT1)-old+(FR-Frm)×ZBAA×(TMOT-TMOT1)/(TMOT2-TMOT1)
and
FBAA2(TMOT2)-new=FBAA2(TMOT2)-old+(Fr-Frm)×ZBAA×(TMOT2-TMOT)/(TMOT2-TMOT1)
In this way, the adaptive correction factor is assigned to the associated engine temperature.
The adaptation factor FBAA influences a characteristic FBAAM in a non-volatile RAM, which is stored as a function of the engine temperature. The learned adaptation factor adjusts the values of the characteristic at the support points between which it is located, in accordance with the principle of inverse interpolation. The further the engine temperature support point of the characteristic value is from the actual temperature, the weaker the adjustment of said value.
Since there is no information available from the conventional lambda regulator when the engine is cold, two other criteria are used for adaptation.
Use is made of a recently available heated problem, which can be made warm enough to provide a usable signal [lambda>1 (lean or lambda <1 (rich)] within a short time, even when the engine itself is cold.
During the engine warm-up time such a lambda probe normally (not an acceleration condition), indicates the signal lambda <1 (rich). If then, after a dead time TBA following acceleration enrichment being triggered there occurs with a time TSU a change in the probe output such that it indicates lambda <1 (lean mixture) this means that the mixture became leaner during acceleration enrichment. It can then be concluded that the acceleration enrichment factor must be increased.
However, in this way it cannot be recognized whether there has been excess enrichment during an acceleration enrichment.
To recognize the excess enrichment, a further criterion is required. This criterion can be derived from the engine speed curve. If the speed drops rather than increases following triggering of an acceleration enrichment, then there was excess enrichment during the acceleration enrichment. In this case, the adaptation factor must be reduced.
A drop in speed is established by comparing the speed at the instant of acceleration enrichment triggering with the speeds within the time TBA. If the actual speed is below the speed at the moment of acceleration enrichment triggering, a speed drop flag is set in the control device.
In some cases, it may be necessary to form a more differentiated "speed drop" criterion. Instead of comparing it with the actual speed, it could be compared with the average value of the speeds, whereby this average value is recalculated following each acceleration enrichment triggering. As a result, fluctuations in speed caused by a tendency to jolt would not set the speed drop flag.
Thus, if the λ probe continues to show λ<1 (rich) during acceleration enrichment and there is an engine speed drop, then it can be concluded that that acceleration enrichment was too great. The acceleration enrichment factor is then arranged to be reduced the next time that acceleration enrichment is provided.
On the other hand, if the λ probe changes to indicate a lean mixture (λ<1) during acceleration enrichment and there is an engine speed drop, then it can be concluded that that acceleration enrichment was too weak. The acceleration enrichment factor is then arranged to be increased the next time that acceleration enrichment is provided.
The above-described operation is illustrated in the form of simplified flow diagrams in the accompanying FIGS. 1 to 4.
As shown in FIG. 1, the injection quantity ti is calculated, as described hereinbefore, taking into account a previously established enrichment factor map in accordance with
ti=tL.Fi.Fba(t)+TVUB
where Fba(t)=FBa(o)-DTBAM.t
t being zero when the acceleration enrichment is triggered,
Fba(t) always being greater than one and
Fba(o) being given by FBAM.KFBA.FBA .FBAAM
The method by which the adaptive factor FBAAM is established depends upon whether the λ regulator control is active or not, that is upon whether the engine has reached its normal operating temperature or not. If the λ regulator is active, then the engine has warmed up and adaptive acceleration enrichment is based "with λ control" upon the λ regulator value Fr and its comparison with the average value Frm, as described above.
On the other hand, if the λ regulator is not yet active and the engine is therefore still warming up, then provided that the λ probe itself has been heated up sufficiently, adaptive enrichment is made "without λ control" on the basis of the λ probe signal and the presence or absence of engine speed drops during the previous enrichment period. It is of course with the latter warming-up phase that the present invention is primarily concerned and so that operations performed during this phase are described in more detail in the flow diagrams of FIGS. 2 and 3.
FIG. 2 illustrates part of a main processing routine which is effective during the warming-up phase of the engine when the λ regulator is not active.
Point 10 indicates the part of the routine where normal fuel injection pulses are generated based on the usual engine parameters such as load t1 and engine speed n. On detection of an acceleration demand at point 12, a routine 14 is activated for the calculation of an acceleration enrichment factor (BA) and acceleration enrichment is triggered at 16.
As explained above, due to the inevitable dealy in the λ probe reacting to a change in the fuel quantity injected, no attempt is made to make any adjustment to the acceleration enrichment factor during a current enrichment process. Rather, what happens during that enrichment is monitored and used after the end of that enrichment step to modify the enrichment factor appropriately for the next enrichment step.
Thus, a decision is made at point 18 as to whether fuel enrichment is still running for that particular acceleration operation. If it is, then a check is made at point 20 to establish whether the λ probe is ready for operation, i.e. is it heated up sufficiently. If it is not, then the routine returns to the beginning 10. If it is, a check is made at 22 as to whether there has been a drop in engine speed during the acceleration enrichment period. If there has not, then the routine returns to the beginning 10. If there has, then the λ probe is monitored to check for any change in its output to the lean mixture condition (λ>1). Any such change and the speed drop are transferred to RAM within a control computer for future use.
When it is detected at point 24 that a fuel enrichment operation has just finished, checks are made on the stored signals to establish whether the λ probe was ready for operation (point 26) and whether there had been a drop in engine speed during the enrichment operation (point 28). If the answer is positive, it is checked at pint 30 whether there was a change in the λ probe output from a rich (λ<1) to a lean (λ>1) during the enrichment operation. If the answer is negative, then it is concluded (point 32) that the enrichment was too great and steps are taken (see FIG. 3) to reduce the adaptation performed at point 14 next time acceleration enrichment is required. On the other hand, if the answer is positive, then it is concluded (point 34) that the enrichment was insufficient and steps are taken to increase the adaptation at point 14 next time.
Adaptive enrichment without active lambda control is illustrated in more detail in the flow diagram of FIG. 3.
When acceleration enrichment is triggered at point 36, a counter is started (point 38) which counts out the period TBA. The "speed drop" flag is re-set (point 40) in the computer and the current engine speed (n=n BA ) is recorded (point 42).
During the period that the TBA counter is still running (point 44), a check is made at point 46 as to whether the current engine speed n is less than the recorded speed n BA at the time acceleration enrichment was triggered. If it is less, then the "speed drop" flag is set (point 48). When it is detected at point 50 that the TBA counter had just stopped, then a second counter is started which counts a period TSU (52). While the counter TSU is running, a check is made at point 54 or whether the λ probe is indicating a lean mixture (λ>1). If it is, then the "probe lean" flag is set. When it is detected at point 56 that the TSU counter had jut stopped, a check is made at point 58 whether the "speed drop" flat is set. If it is, then it is checked whether the "probe jump" flag was set. If it was, then it is concluded that the acceleration enrichment was too lean during the previous enrichment operation so that the enrichment factor must be increased. A explained above, this is achieved by adjusting the two support points of the FBAAM map upwards in accordance with ##EQU1##
On the other hand, if it is found that the "probe jump" flag has not been set, it is concluded that the acceleration enrichment was too great during the previous enrichment operation so that the enrichment factor must be reduced. This is achieved by adjusting the two support points of the FBAAM map downwards in accordance with: ##EQU2##
FIG. 4 illustrates in more detail a flow chart of the routine which achieves the operation described initially for adaptive enrichment with active lambda control, that is when the engine is fully warmed up. In this case, the decision whether to increase or decrease the acceleration enrichment factor is made on the basis of whether the difference between the current lambda control output Fr and and the stored average value Frm is positive or negative and above predetermined threshold levels DFRP, DRRN, as described above.
Using the above-described techniques, satisfactory adaptive acceleration enrichment (BA) can be maintained during acceleration even when the engine is cold. The conversion rate of the exhaust catalyzer thus remains optimized. Neither is there any deterioration in performance due to varying engine conditions such as, for example, in the event of coking. Extreme coking intake passages reduce charging and hence impair performance to an unacceptable level. Adaptation can also be used in diagnosing such a condition of the engine. The adaptation value for the acceleration enrichment can be read out from non-volatile RAM. If the value is very large, it is likely that the engine valves are badly coked and must be cleaned. | A petrol injection system for an internal combustion engine, the system being adapted to provide additional petrol into the inlet manifold of the engine during acceleration conditions in order to compensate for the less efficient transference of vaporized fuel to the engine cylinders during acceleration conditions, the quantity of additional fuel (BA) being determined in accordance with a stored enrichment value (FBAAM) which is adjusted regularly to take into account changing engine conditions. During the warming-up phase of the engine when the normal lambda regulation is inactive, the magnitude and direction of adjustment of the acceleration enrichment value (FBAAM) is derived from the behavior of the rotational speed (n) of the engine and the λ probe signal (λ>1 or λ<1) during an acceleration enrichment operation in that if, during an acceleration enrichment operation in the warming-up phase of the engine, it is detected that the λ probe output continues to indicate a rich mixture (λ>1) and that there was an engine speed drop, it is concluded that the acceleration enrichment factor is too high and steps are taken to reduce it. However, if it is detected that the λ probe has changed to indicate a lean mixture and that there was an engine speed drop, it is concluded that the acceleration enrichment factor is too low and steps are taken to increase it. | 5 |
This application claims the benefit of U.S. Provisional Application(s) No(s). 60/170,036 Filing Date: Dec. 10, 1999.
FIELD OF INVENTION
The present invention relates to methods of modulating nicotinic receptors by use of analogs of galanthamine and lycorarmine. Modulation of such receptors is useful in improving attentional functions, relieving pain, treating nicotine and similar addictions, treating anxiety and depression, treating and retarding the progression of Alzheimer's and Parkinson's diseases, neuroprotection against neurodegenerative disorders, alcohol, glutamate and other toxic effects and treatment of schizophrenia.
BACKGROUND OF THE INVENTION
Galanthamine is an alkaloid isolated initially from galanthus nivalis, the snowdrop, which has been used for many years as an acetyleholinesterase inhibitor. The principal use in humans has been the postoperative reversal of neuromuscular blockade. It has also been administered in number of neuromuscular diseases. Because of the activation of muscle, it was of interest to determine the relationship between galanthamine's anticholinesterase activity and its ability to induce twitch potentiation in muscle.
In intact cats, twitch potentiation of the gastrocnemius by direct electric stimulation was measured after intravenous infusion of neostigmine, physostigmine and galanthamine. (Ueda M, Matsumura S, Kimoto S, Matsuda S, Studies on the anticholinesterase and twitch potentiation activities of galanthamine. Jap J Pharmacol 12:111-119, 1962) Galanthamine was 1/10.5× as active as neostigmine and 1/3.5× as active as physostigmine. (p 114) The IC 50 for cholinesterase inhibition, measured in rat brain, erythrocytes, or gastrocnemius homogenate, is in the range of 200 times lower for neostigmine, and 50 times lower for physostigmine than for galanthamine. (Table 4, p 115) This produced a disproportion between the magnitude of twitch potentiation and the enzymatic activity. The authors note
“Although the anticholinesterase activity of galanthamine is far inferior to those of neostigmine and physostigmine, the twitch potentiation by galanthamine administration is only {fraction (1/10)} of that of neostigmine or physostigmine. So it is presumed that factors other than anticholinesterase activity are concerned with the twitch potentiating effects of galanthamine.”
In their discussion, they review this point.
“Although the anticholinesterase activity of galanthamine is about {fraction (1/100)} that of neostigmine or physostigmine, the twitch potentiating effects of galanthamine in the nerve muscle preparation is about {fraction (1/10)} of the latter. These contradictions between the twitch potentiation and anticholinesterase activity are also not solved by the direct effects of galanthamine on the muscle fibres or by the difference of species in the experimental animals.”
The authors consider that the effects of galanthamine may not represent either anticholinesterase activity, or a direct effect, such as would be expected from a depolarizer. They cite the arguments of prior authors that the classical view of acetylcholine accumulation at the neuromuscular junction was inconsistent with “the following points; (1) Potent depolarizers do not necessarily show the marked twitch potentiation. (2) Twitch potentiations caused by anticholinesterase like neostigmine appeared soon after the administration of the compound.” Thus, the enhancement of the activity of endogenous transmitter released by electrical stimulation was neither consistent with the time course or potency of anticholinesterases, nor could it be attributed to direct depolarization. Therefore, twitch potentiation was most likely attributable to an action on motor nerve terminals other than enzyme inhibition or direct agonism.
Motor nerve terminals, i.e., the neuromuscular junction, functions by means of a nicotinic cholinergic recepter. Such receptors are found also in ganglia. Kostowski and Gomulka (Note on the ganglionic and central actions of galanthamine, Int J Neuropharmacol, 7:7-14, 1968) investigated the effects of galanthamine and physostigmine on ganglionic transmission in the cat. The drugs were administered intra-arterially and depolarization was recorded from the surface of the superior cervical ganglion. Physostigmine and galantamine were administered in comparable doses, 250 micrograms, which represent fairly equal molarity, as the molecular weight of physostigmine salicylate is 413 and that of galanthamine hydrobromide is 368. As noted above, this represents much greater anticholinesterase potency for physostigmine. As shown in FIG. 1A, p 9, galanthamine, but not physostigmine, substantially inhibited hexamethonium (C6) induced ganglionic blockade. Direct recordings are shown in FIG. 2, p 10, in which preservation of the surface potential is shown in galanthamine, but not physostigmine-treated ganglia. The authors considered that differential penetrability might contribute to these results, but that
“the differences in the direct actions of the drugs on ganglionic cholinoceptive sites should also be taken into consideration. In the superior cervical ganglion of the cat, two distinct excitatory cholinoceptive sites have been described . . . The first is activated by nicotine, tetramethylammonium (TMA) and inhibited by curare or hexamethonium-like drugs, whereas the second type is characterized by its sensitivity to muscarine and acetyl-b-methylcholine excitation and to blockade by atropine. Both types of cholinoceptive sites, muscarinic and nicotinic, can be activated by acetylcholine . . . The ability of galantamine to prevent the C6 induced ganglionic blockade suggests that this effect seems to be due to excitation of ‘nicotinic cholinoceptive sites’. . . The increase in ganglionic surface potential in ganglia treated with galantamine also supports the hypothesis that such a mechanism is involved in the action of some anticholinesterases.”
Recent observations are consistent with the mechanisms proposed by the early authors. Using clonal rat pheochromocytoma (PC12) cells, Storch et al confirmed the conclusions of Ueda more than thirty years earlier. (Storch A, Schrattenholz A, Cooper J C, Abdel Ghani E M, Gutbrod O, Weber K-H, Reinhardt S, Lobron C, Hermsen B, Soskic V, Periera E F R, Albuquerque E X, Methfessel C, Maelicke A, Physostigmine, galanthamine and codeine act as ‘noncompetitive nicotinic receptor agonists’ on clonal rat pheochromocytoma cells. Eur J Pharmacol Mol Pharmacol Sect 290:207-219, 1995)
The authors note that “physostigmine, galanthamine and codeine do not evoke sizable whole-cell currents, which is due to the combined effects of low open-channel probability, slow onset and slow inactivation of response.” These agents require an ion channel which has been opened, as can be done by a direct agonist, in order to have an effect. Physostigmine and galanthamine do, however, cause some channel activation in inside-out patches from PC 12 cells. This activation can also be produced by acetylcholine. Methyllycaconitine, a competitive nicotinic antagonist, blocks the activation by acetylcholine, but not by the cholinesterase inhibitors. (FIG. 2, p 211) Galanthamine and physostigmine are, therefore, not binding at the agonist site. On the other hand, after incubation with FK1, a competitive monoclonal antibody to physostigmine, neither physostigmine nor galanthamine could induce single channel activity, while acetylcholine still could. The authors conclude “In other words, (−)-physostigmine (and galanthamine) [that is the authors's addition in parentheses] acted as noncompetitive agonists at nicotinic receptors of PC12 cells.” (p213)
Thus, the ability of galanthamine to enhance activation of motor nerve terminals stimulated electrically, to increase ganglionic depolarization induced by acetylcholine and to protect against hexamethonium, indicating enhancement of the activity of nicotinic receptors, has been confirmed with the newer methods of patch-clamp and antibody techniques.
SUMMARY OF THE INVENTION
The present invention provides a method for modulating nicotinic by administering an effective amount of a galanthamine or lycoramine analog to a patient in need of such modulation.
DETAILED DESCRIPTION OF THE INVENTION
Analogs of galanthamine that are of use in the present invention are those having good nicotinic properties. Classical neurochemical techniques, such as employed by Kostowski and Gomulka (op cit) may be used to identify compounds with nicotinic properties. In these, an outcome measure known to be cholinergic, such as an electrical potential or other biological function, is blocked with a nondepolarizing agent such as hexamethonium. Newer techniques, such as patch-clamp recordings in hippocampal slices (Alkondon M, Pereira E F, Eisenberg H M, Albuquerque E X, Choline and selective agonists identify two subtypes of nicotinic acetylcholine receptors that modulate GABA release from CA1 interneurons in rat hippocampal slices. J Neurosci 19(7):2693-2705, 1999), current and voltage clamp modes, (Frazier C J, Rollins Y D, Breese C R, Leonard S, Freedman R, Dunwiddie T V (Acetylcholine activates an alpha-bungarotoxin-sensitive nicotinic current in rat hippocampal interneurons, but not pyramidal cells. J Neurosci 18(4)1187-1195, 1998) or electrophysiological recordings (Stevens K E, Kem W R, Freedman R, Selective alpha 7 nicotinic receptor stimulation normalizes chronic cocaine-induced loss of hippocampal sensory inhibition of C3H mice. Biol Psychiatry 46(10)1443-50, 1999), or techniques such as employed by Storch et al, above, may be also be used to identify compounds which are candidates for appropriate safety, pharmacokinetic and finally studies in humans. In addition, pharmacological reversal trials with nicotinic receptor inhibitors such as hexamethonium mecamylamine, methylyaconitine dihydro beta erythroidine may be used to identify nicotinic mechanisms.
Such compounds include analogs wherein at least one of the methoxy, hydroxy or methyl groups of galanthamine or lycoramine is replaced as follows:
the methoxy group by another alkoxy group of from one to six carbon atoms, a hydroxy group, hydrogen, an alkanoyloxy group, a benzoyloxy or substituted benzoyloxy group, a carbonate group or a carbamate group or a trialkylsilyloxy group;
the hydroxy group by an alkoxy group of from one to six carbon atoms, hydrogen, an alkanoyloxy group, a benzoyloxy or substituted benzoyloxy group, a carbonate group or a carbamate group;
the N-methyl group by hydrogen, alkyl, benzyl, cyclopropylmethyl group or a substituted or unsubstituted benzoyloxy group.
Other suitable analogs may be found for example in International Patent Publication W088/08708 and an article by Bores and Kosley in Drugs of the Future 21:621-631 (1996).
Alkanoyloxy, carbamate and carbonate groups of use in the compounds of the present invention typically contain up to ten carbon atoms. The substituent groups, are typically selected from alkyl or alkoxy groups of from 1 to 6 carbon atoms, halo groups, and haloalkyl groups such as trifluoromethyl. When reference is made to alkyl groups, where the context permits, the term also include groups which are or contain cycloalkyl groups including adamantyl groups. Aryl groups are typically phenyl or naphthyl but may include heteroaryl such as morpholino. The carbamate groups may be mono or di-substituted and in the case of disubstituted carbamates, each of the groups may be as just specified. For example a dimethyl carbamate group may be used.
Galanthamine has the following structure:
Lycoramine is similar but has only a single bond between the 3 and 4 positions.
Particularly useful analogs of galanthamine and lycoramine for use in the present invention include analogs thereof wherein the hydroxy and/or methoxy groups are replaced by carbamate groups, for example 2-n-butyl carbamates.
Other compounds that may be of use are those wherein the methoxy group of galanthamine or lycoramine is replaced by a hydrogen, hydroxy or alkoxy group of from two to six carbon atoms or an acyloxy group, for example an alkanoyloxy or benzoyl group, of from one to seven carbon atoms, more preferably of two to seven carbon atoms. Other compounds that may be of interest are those wherein the methoxy group is replaced by a mono or dialkyl carbamate or carbonate group wherein the alkyl groups contain from 1 to 8 carbon atoms, preferably of from 4 to 6 carbon atoms or wherein the methoxy group thereof is replaced by an aryl carbamate or carbonate group wherein said aryl group is selected from phenyl, naphthyl, substituted phenyl and substituted naphthyl groups wherein said substituent is selected from alkyl and alkoxy groups of from 1 to 6 carbon atoms, trifluoro methyl groups and halo groups. Care should, however, be taken with such 13-carbamates to ensure that there are no toxicity problems with the intended method of use.
Other useful analogs include compounds wherein, independently of whether or not the methoxy group has been replaced, the hydroxy group is replaced by an alkoxy group of from one to six carbon atoms, hydrogen, an acyloxy group, for example an alkanoyloxy group, typically of from 1 to 7 carbon atoms, a benzoyloxy or substituted benzolyloxy group wherein said substituent is selected from alkyl and alkoxy groups of from 1 to 6 carbon atoms, trifluoro methyl groups and halo groups, or a carbonate group, preferably or a carbamate group which may be a mono or dialkyl or an aryl carbamate or carbonate wherein the alkyl groups contain from 1 to 8 carbon atoms, preferably of from 4 to 6 carbon atoms or said aryl group is selected from phenyl, naphthyl, substituted phenyl and substituted naphthyl groups wherein said substituent is selected from alkyl and alkoxy groups of from 1 to 6 carbon atoms, trifluoro methyl groups and halo groups.
Analogs of galanthamine may be developed to enhance nicotinic receptor modulation relative to cholinesterase inhibiting ability. These could be useful in a large number of conditions, reviewed by Lena and Changeux. (Lena C and Changeux J-P, Pathological mutations of nicotinic receptors and nicotine-based therapies for brain disorders. Current Opinion in Neurobiology 7:674-682, 1997) Congenital myasthenia gravis, some cases of which are due to increase of function in the muscle nicotinic receptor, could benefit from an analog with allosteric inhibitory properties. Other diseases associated with functional point mutations in nicotinic receptors are autosomal dominant frontal lobe epilepsy and human hereditary hyperekplexia.
In Alzheimer's disease, nicotine has been shown to enhance cognition. Moreover, demographic and laboratory evidence suggests neuroprotective properties of nicotine in Alzheimer's disease, in Parkinson's disease, where therapeutic effects have also been reported, and against neurotoxic manipulations such as glutamate administration, nerve growth factor deprivation, and ethanol administration. (See also Court J A, Lloyd S, Perry R H, Griffiths M, Morris C, Johnson J, McKeith I G, Perry E K, The nicotinic cholinergic system and beta-amyloidosis, in Alzheimer Disease: From Molecular Biology to Therapy, Becker R and Giacobini E, eds, Birkhauser, Boston, 1996; Kihara T, Shimohama S, Akaike A, Nicotinic receptor stimulation protects neurons against glutamate- and amyloid-beta-induced cytotoxicity, in Alzheimer's Disease and Related Disorders, Iqbal K, Swaab D F, Winblad B and Wisniewski H M, eds, John Wiley & Sons Ltd, Chichester, 1999; Yamashita H and Nakamura S, Nicotine rescues PC12 cells from death induced by nerve growth factor deprivation. Neuroscience Letters 213:145-147, 1996; Li Y, Meyer E M, King M A, Nicotinic receptor mediated signal transduction against ethanol and amyloid cytotoxicity, Abstract No. 394.17, Society for Neuroscience, Volume 25, 1999). Thus, augmentation of nicotinic receptor function may produce functional improvements in Alzheimer's disease and Parkinson's disease and reduce neurodegeneration.
Compounds that could eliminate or reduce nicotine dependence, or that of other drugs operating through the same brain mechanisms, in smokers would be useful. Nicotinic drugs may also be of value in the treatment of Tourette's Syndrome, and to improve attention. A particular attentional deficit, auditory gating, (although other attentional paradigms show similar results) found commonly in schizophrenia but also in 50% of first-degree relatives, can be reversed by nicotine. Thus, analogs with nicotinic properties may be employed in a variety of situations in which it is desirable to normalize or improve attentional functions.
Dosages for suitable agents can be determined by standard techniques such as those set out for example in Chapter 6 (by Benjamin Calesnick) of Drill's Pharmacology in Medicine (Fourth Edition Joseph R. DiPalma ed, McGraw-Hill 1971 or in Chapter 6 (by B. E. Rodda et al) of Biopharmaceutical Statistics for Drug Development (ed. Karl E. Peace, Marcel Dekker Inc. 1988). | Analogs of galanthamine and lycoramine are useful in modulating nicotinic receptors in humans and other animals. Modulation of such receptors is useful in treatment and/or prevention of a number of conditions including but not limited to treatment of attention disorders, assistance in giving up smoking and in treatment of Parkinson's disease. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. patent application Ser. No. 10/783,667 entitled “Inflatable Cushioning Device” filed with the U.S. Patent and Trademark Office on Feb. 20, 2004, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This application relates to devices for protecting vehicle occupants and more particularly (but not exclusively) to curtains or other cushions designed to inflate when a vehicle is impacted. The cushions are especially adapted as protective designs when side-impact collisions occur and are intended to reduce likelihood of occupants being ejected from the vehicle. They may, however, be useful in other circumstances and perform other protective functions too.
FIELD OF THE INVENTION
[0003] Commonly-owned U.S. Pat. No. 5,322,322 to Bark, et al., whose contents are incorporated herein in their entirety by this reference, describes an existing protective system for vehicle occupants. Versions of the system, designed to be mounted along the periphery of a side window of a vehicle (at or near the roof rail), include but are not limited to a braided tube containing a gas generator. As noted in the Bark patent:
When a side impact is detected, the gas generator is ignited, inflating the braided tube. As the braided tube inflates, the diameter of the tube increases and its length decreases. The tube then pulls out of its storage location and forms a taut, semi-rigid structural member across the vehicle's window.
See Bark, Abstract, 11. 7-12.
[0005] Because vehicle rollovers sometimes also occur, inflatable curtains have been devised in attempts to reduce adverse effects of the rollovers to vehicle occupants. Many existing curtains are slow to deploy, however. Others fail to develop sufficient contraction for tension near or at the vehicle beltline to prevent occupant ejection.
[0006] One set of improved curtains is illustrated in U.S. Pat. No. 6,505,853 to Brannon, et al., whose contents are incorporated herein in their entirety by this reference. Like other inflatable curtains, the ones of the Brannon patent are “inflatable from the roof of the vehicle downward,” see Brannon, col. 1, 1. 15; col. 3, 11. 45-47, and lack any braided portion. Instead, these curtains, when deployed, tension a helical portion of an elongated member by increasing both its diameter and length. See id., col. 3, 11. 55-67. Additionally, because these curtains inflate from the roof of the vehicle downward, their inflators and mounting equipment are typically fixed to the vehicle and thus unable to move.
[0007] As headroom in and interior space of larger personal vehicles (such as sport-utility vehicles, or “SUVs”) increases, utilizing existing devices to protect human occupants is becoming increasingly difficult. Compounding this issue is the wide range of heights and sizes of potential occupants, as statistically, optimizing device inflation for a male having height and weight in the ninety-fifth percentile among men, for example, might result in less-than-optimal head (and body) protection for a female with height and weight in the fifth percentile among women. Conversely, optimizing device inflation characteristics for small women might result in less-than-optimal protection for large men.
SUMMARY OF THE INVENTION
[0008] The present invention provides alternatives to the inflatable devices of, for example, the Bark and Brannon patents. Utilizing braids—similar to those of the Bark patents—at the lower edges (with “lower” being defined while the vehicle is upright), devices of the present invention comprise curtains or other cushioning devices adapted to inflate from the lower portions upward. Doing so creates an inflation pattern opposite that of conventional curtains, allowing for greater uniformity in tension at the lower edges and rapid deployment of the devices. Because inflated from their lower portions upward, devices of the present invention effectively “pull” the corresponding curtains out of their covers rather than only “push” them out, as is done with existing curtains.
[0009] Embodiments of the invention additionally may include inflatable nodes extending outward through portions (such as through the braid or knit) of the devices. In these embodiments, the braid need not necessarily exist at the lower edges of the devices. Regardless of braid placement, however, including such additional inflatable material may enhance protection of various portions of bodies of human occupants notwithstanding their potentially-differing heights and sizes. Due to the structure created by the braided material when inflated, robust locating of inflatable sections can be achieved more easily.
[0010] Versions of the present invention typically comprise an elongated cover in which an inflatable curtain or other cushioning apparatus is placed when deflated. Such cover advantageously is mounted to or near the roof rail of a vehicle, although it may be mounted elsewhere as appropriate or desired. Incorporated into the curtain is a braided, inflatable tube (or similar knitted or other structure). Preferably, the tube spans the lower edge of the curtain, although it need not necessarily do so.
[0011] When the braided tube is inflated, it decreases in length while its diameter increases. This action pulls the curtain out of the cover and tensions the lower edge, creating a taut, generally linear, semi-rigid structure helping reduce the risk of occupant ejection through the side window during a vehicle crash such as a rollover. Because the (deploying) lower portion of the curtain is being inflated, the inflation device for the curtain will travel along with the braided tube. The braided material can be designed in a non-homogenous fashion such that the cross-section of the braided section changes as one travels along the length of the vehicle. This is advantageous in the area of the seat, where the allowable space for the curtain to deploy is limited. By reducing the cross-section in this area, improved trajectory of the curtain can be achieved.
[0012] Optionally extending upward from the tube within the curtain are one or more inflatable nodes. These nodes are fluidly connected and may be inflated concurrently with the braided tube (through slots or other openings therein), so that inflation occurs upward from their lower edges. The nodes function primarily to cushion an occupant's head in an attempt to reduce head injury to occupants when a vehicle collision occurs. Depending on their placement they may, however, provide some torso or thoracic protection as well. The placement of a node may be downward to provide torso protection such as by inserting the inflated node between the occupant's shoulder and the intruding vehicle structure. The node may affirmatively push an occupant's shoulder inboard reducing the effects of contact and interaction between the occupant and the intruding vehicle. Due to the stress on the fabric from the inflation gas flowing from the first section to the nodes, a bonded construction may be used in place of traditional sewing to ensure retention of the gas under these high stresses.
[0013] Moreover, although the invention is designed principally with regard to side-impact and rollover situations and to reduce the risk of ejection or head injury, its concepts may be used in other circumstances or for protection of other parts of the body as well. Alternatively, the braid may be attached to the outside (rather than incorporated within) the curtain in some embodiments of the invention. In such circumstances the braid likely will have a U-shaped, instead of (generally) circular, cross-section so as not to interfere with inflation of the nodes.
[0014] It thus is an optional, non-exclusive object of the present invention to provide inflatable cushions that inflate from lower portions to upper portions (with “lower” defined when the vehicles in which the cushions are placed are upright).
[0015] It is another optional, non-exclusive object of the present invention to provide inflatable cushions that include braided, knitted, or other components designed to contract to create tension linearly.
[0016] It is also an optional, non-exclusive object of the present invention to provide inflatable cushions in which an inflation device travels with the braided tube during deployment.
[0017] It is a further optional, non-exclusive object of the present invention to provide inflatable cushions with inflatable nodes.
[0018] It is yet another optional, non-exclusive object of the present invention to provide inflatable nodes that inflate from their lower edges to their upper edges.
[0019] It is another optional, non-exclusive object of the present invention to provide inflatable nodes that inflate from their lower edges of the tubular braid structure downward to interpose themselves between the shoulder or torso of the occupant and the intruding vehicle structures during a crash.
[0020] It is, moreover, an optional, non-exclusive object of the present invention to provide inflatable cushions adapted to reduce risk of injury during side-impact collisions and vehicle rollovers.
[0021] Other objects, features, and advantages of the present invention will be apparent to those skilled in the relevant art with reference to the remaining text and the drawings of this application.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 illustrates an exemplary cushioning device, in the form of a curtain, in an undeployed state.
[0023] FIG. 2 illustrates the device of FIG. 1 when partially deployed.
[0024] FIG. 3 illustrates the device of FIG. 1 when fully deployed.
[0025] FIG. 4 illustrates a first alternative cushioning device, in the form of a curtain to which braided material has been added, in a deployed state.
[0026] FIG. 5 illustrates an alternative cushioning device, in the form of a tubular structure with nodes, in a deployed state.
[0027] FIG. 6 illustrates an alternative cushioning device, in the form of a tubular structure with downward nodes, in a deployed state.
DETAILED DESCRIPTION
[0028] FIGS. 1-3 detail device 10 of the present invention. As shown in FIGS. 1-3 , device 10 is mounted to side structure S of vehicle V, generally along the upper periphery of windows W adjacent roof rail R. Although these figures illustrate a presently preferred mounting position of device 10 , the device 10 may be mounted, or otherwise attached to or within vehicle V, differently than is shown in FIGS. 1-3 .
[0029] Included as parts of device 10 are cover 14 , inflatable curtain 18 , and inflator 22 . As illustrated in FIG. 1 , most or all of curtain 18 is positioned within, and thereby protected by, cover 14 when uninflated. While advantageous to utilize cover 14 , it is not absolutely necessary for use of device 10 . If present, though, cover 14 may incorporate a tear-away seam or other mechanism permitting egress of curtain 18 for deployment. Likewise, device 10 may include a fill tube for facilitating fluid communication between inflator 22 and curtain 18 , although such fill tube too is not absolutely necessary.
[0030] As best illustrated in FIG. 3 , curtain 18 beneficially comprises lower portion 26 defining lower edge 30 and upper portion 34 defining upper edge 38 . In the version of device 10 depicted in FIG. 3 , lower portion 26 includes a braided tube (an example of which is identified as tube 42 of FIG. 5 ). Upper portion 34 , by contrast, includes nodes 46 separated by uninflated sections 50 . Although four nodes 46 are illustrated in FIG. 3 , fewer or greater numbers of nodes 46 may be present in any particular device 10 . Additional nodes may also point out in any radial direction from the center of the braided section. In this manner, the nodes can be adapted to offer additional protection for any given requirement of occupant protection.
[0031] Curtain 18 may be constructed of any appropriate materials. Conventional air bag fabrics and materials may, for example, be used. Similarly, braided tube 42 may be sewn to or otherwise incorporated into curtain 18 . Braided tube 42 itself may be constructed as described in the Bark patent. It need not necessarily be tubular, however, and instead could form other shapes when inflated. (Furthermore, those skilled in the art will recognize that, in certain circumstances, other materials adapted to provide taut, semi-rigid structures when inflated may be used in place of tube 42 .)
[0032] Viewed sequentially, FIGS. 1-3 illustrate deployment of curtain 18 . As noted earlier, FIG. 1 depicts device 10 with curtain 18 uninflated and vehicle V upright, the normal operating mode for both device 10 and vehicle V. Should a sensor associated with vehicle V detect a collision (or any other deployment-worthy event), it signals inflator 22 to inflate curtain 18 .
[0033] FIG. 2 shows early-stage inflation of device 10 (at, nominally, approximately five milliseconds), with the remainder of curtain 18 being pulled downward from its upper edge 38 . FIG. 3 details full inflation of curtain 18 , with both tube 42 and nodes 46 fully inflated. With tube 42 fully inflated, it forms a taut, semi-rigid, generally linear structural member whose ends 54 and 58 are directly or indirectly (through inflator 22 ) attached to a side of vehicle V, which assists in maintaining the positioning and rigidity of curtain 18 regardless of orientation of the vehicle V.
[0034] Also shown in FIG. 3 by arrows are the fluid paths used to effect inflation of device 10 . Gas generated by or via inflator 22 enters tube 42 in the lower portion 26 of curtain 18 , travelling within tube 42 to inflate it. As gas travels within tube 42 , it encounters nodes 46 , with some of the gas diverting to fill the nodes 46 . As is clear from FIG. 3 , curtain 18 thus inflates from its lower portion 26 upward, opposite the process conventionally used for inflating curtains. Equally clear from FIGS. 1-3 is that lower portion 26 of curtain 18 moves downward as inflation occurs, and that inflator 22 pivots, or otherwise moves, in conjunction therewith.
[0035] FIG. 4 illustrates an alternative device 10 A of the present invention. Device 10 A may be similar to device 10 , albeit with braided material 62 positioned externally of lower portion 26 A of curtain 18 A. Because sewn or otherwise attached to the exterior of curtain 18 A, braided material 62 preferably has a U-shaped (rather than circular) cross-section, so as not to impede inflation of nodes 46 A. In use, braided material 62 functions as does tube 42 , decreasing in length and increasing in width as curtain 18 A inflates in order to form a relatively taut, semi-rigid member.
[0036] Because both devices 10 and 10 A utilize braid generally horizontally attached to or within respective curtains 18 and 18 A, substantially the entire lengths of tube 42 and material 62 are available to transfer loads. Consequently, point-loading issues associated with prior devices are reduced. Utilizing braid additionally provides greater mechanical strength to devices 10 and 10 A and permits greater tension to be achieved than with existing devices. Incorporating inflatable nodes 46 or 46 A into devices 10 or 10 A additionally improves performance, as head-impact energy may be transferred to gases within nodes 46 or 46 A rather than solely into a tensioned piece of fabric.
[0037] Detailed in FIG. 5 is another alternative device 10 B. Device 10 B includes some features of devices 10 and 10 A yet is not in the form of a curtain. Instead, as deployed (as shown in FIG. 5 ), device 10 B more closely resembles the systems of the Bark patent, albeit with one or more inflatable nodes 46 B protruding upward from braided tube 42 .
[0038] The foregoing is provided for purposes of illustrating, explaining, and describing exemplary embodiments and certain benefits of the present invention. Modifications and adaptations to the illustrated and described embodiments will be apparent to those skilled in the relevant art and may be made without departing from the scope or spirit of the invention. As non-limiting examples, nodes 46 or 46 A alternatively could extend downward from tube 42 or material 62 , respectively, in appropriate circumstances, and regardless of orientation could attempt to provide torso protection either in addition to or instead or protection for the head of an occupant. Additionally, although devices 10 , 10 A, and 10 B are designed principally for use in automobiles and other land-based vehicles, they may be used in other vehicles or for other purposes as appropriate or desired. | Inflatable devices principally for vehicle occupant protection are addressed. Included among the devices are curtains or other cushions ( 18 ) with braided portions ( 42 ) along their lower edges ( 30 ) designed to form semi-rigid members when deployed. Unlike commercially-available vehicle curtains, inflation occurs from the bottom (where the semi-rigid member is formed) upward. The devices additionally optionally may include inflatable nodes ( 46 ) within the curtains ( 18 ) or otherwise extending from the cushions. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a centralizer for use in deviated, highly deviated or horizontal well bores to center the casing in the well bore during cementing of the casing in the well bore. More specifically, the invention relates to a semi-rigid floating spring type centralizer for use in deviated, highly deviated or horizontal well bores to center the casing in the well bore during cementing of the casing in the well bore.
Typically prior art centralizers can be generally classified as fixed spring types, floating spring types, rigid types and combinations thereof. There are also various types of knock-down centralizers which may be fixed spring, floating spring, rigid or combination type centralizers.
In deviated, highly deviated or horizontal well bores it is desirable, in order to obtain better results in the cementing of the casing in the well bore, to have the casing in the or near the center of the well bore during cementing operations. If fixed spring and floating spring type centralizers are used, they will need to have high spring forces generated by the springs to ensure that the casing is centered in the well bore. However, these types of centralizers will need to be installed about the casing and held in position by either the casing collars or limit clamps installed on the casing. Since the casing collars and limit clamps will prevent the springs on the centralizers from fully deflecting during running of the casing in the well bore, high starting forces to start the centralizers into the well bore and high running forces to run and reciprocate the casing in the well bore will be present. If rigid type centralizers are used to center the casing in the well bore during cementing operations, the centralizer will be of smaller diameter than the well bore since it is rigid and contains no springs and will merely attempt to maintain a minimum distance between the casing and the well bore during cementing operations.
Combination types of rigid and floating spring type centralizers such as shown in U.S. Pat. Nos. 2,636,564 and 2,728,399 are an attempt to utilize the best features of both types of centralizers. However, since the springs are of a limited number the restoring force may not be sufficient to center the casing in the well bore or due to limited movement of the springs the starting and running forces generated by the centralizer may be high.
BRIEF STATEMENT OF THE INVENTION
The present invention relates to a semi-rigid floating spring type centralizer for use in deviated, highly deviated or horizontal well bores. The centralizer of the present invention comprises a cylindrical tubular housing having a plurality of floating centralizer springs retained thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view of the centralizer of the present invention.
FIG. 2 is an end view of the centralizer of the present invention
FIG. 3 is a view of the end portion of a centralizer spring of the present invention.
The semi-rigid centralizer of the present invention will be better understood when the drawings are taken in conjunction with the description of the invention.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the semi-rigid centralizer 10 of the present invention is shown.
The centralizer 10 comprises a cylindrical housing 12 having a plurality of free floating springs 14 retained thereon by spring retainers 16.
The cylindrical housing 12 comprises an annular elongated cylindrical member which is formed having a diameter slightly larger than the diameter of the casing on which it is to be installed. The cylindrical housing 12 may be formed as a one-piece tubular member, a hinged member or multi-segmented member secured by fasteners to form a cylindrical housing.
Each spring 14 of the plurality of springs 14 on the centralizer comprises an elongated bow-shaped resilient member having a rectangular cross-section with each end 18 of each resilient member being configured in a "T" shape to engage the spring retainer 16 in which it is retained in a fixed but free floating arrangement. If desired, any cross-sectional shaped of material may be used for each spring 14.
Each spring retainer 16 secured to the cylindrical housing 12 comprises a "T" shaped member having a stem portion 20 and a crossbar portion 22. The stem portion 20 is formed having a housing portion 24 secured to the cylindrical housing 12 and an elevated portion 26 secured to the crossbar portion 22 and secured to the housing portion by intermediate portion 28. The crossbar portion 22 is formed having arcuate housing portions 30 secured to the cylindrical housing 12 and elevated spring retention portion 32 which overlies a portion of the end portion 18 of a spring 14 and is attached to the elevated portion 26 of the stem portion 20.
Each spring retainer 16 may be secured to the cylindrical housing 12 by any suitable means, such as welding, as shown, threaded fasteners, rivets, etc. As shown, the outer ends of arcuate housing portions 30 of each spring retainer 16 are welded to the cylindrical housing 12 while the housing portion 24 of the stem portion 20 is also welded to the cylindrical housing 12. The elevated portions 28 of each spring retainer 16 help to guide the centralizer 10 in the well bore when the centralizer 10 is being run into the well bore on casing. If desired, the spring retainer 16 may be formed integrally with the housing 12 through suitable metal forming operations.
Referring to FIG. 2, the semi-rigid centralizer 10 of the present invention is show in an end-view.
As shown, the arcuate housing portions 30 of crossbar portion 22 of the spring retainers 16 are secured to the cylindrical housing 12 as well as housing portion 24 of stem portion 20 of each spring retainer 16.
Also shown in dotted lines in FIG. 2 is the rectangular cross-section of each spring 14.
Referring to FIG. 3, the end portion 18 of each spring 14 is shown as a "T" shaped member. The end portion 18 is formed having a stem portion 34 and crossbar portions 36 formed by notches or cut-outs 38 in each end of spring 14.
When secured to the centralizer 10, the elevated spring retention portion 32 of spring retainer 16 overlies the stem portion of 34 of end portion 18 of spring 14 while crossbar portions 36 extend beyond arcuate housing portions 30 of spring retainers 16. Upon deflection of the spring 14, shoulders 40 of the spring may abut the arcuate portions 30 of spring retainers 16 to prevent further movement of the spring 14 with respect to the spring retainer 16.
OPERATION OF THE INVENTION
Referring to FIGS. 1 through 3, to install the semirigid centralizer 10 of the present invention on casing being run into a well bore, the centralizer 10 is installed between casing couplings and allowed to slide therebetween or may be prevented from substantial sliding on the casing between casing couplings by a limit clamp installed on the casing.
When running casing into the well bore with the semi-rigid centralizer 10 installed thereon, since each end 18 of each spring 14 is free to move independently of the cylindrical housing 12, the initial force required to deflect each spring 14 is reduced upon starting of the centralizer into the well bore as well as the running force required to run the casing with centralizers thereon in the well bore.
When the springs 14 have deflected a predetermined amount, shoulders 40 abut the arcuate portions 30 of spring retainers 16 and any further spring deflection of spring 14 requires a much greater force to be placed on the spring 14 as the end portions 18 of the spring 14 are fixed and cannot move with respect to the cylindrical housing 12.
Since the cylindrical housing 12 of the semi-rigid centralizer 10 loosely fits about the casing on which it is installed, the casing may be rotated or reciprocated in a normal manner during well cementing operations.
Also, when the semi-rigid centralizer 10 is run into the well bore on casing the upper most casing coupling or limit clamp will transmit downward force to the cylindrical housing 12 which, in turn, transmits the force to the lower most spring retainers 16 on the housing 12 which, in turn, transmits the downward force to the end portions 18 of the springs 16 to pull the centralizer into the well bore thereby lowering the starting force to start the centralizer 10 in the well bore and the running force of the centralizer 10 in the well bore. When the casing is moved upwardly in the well bore, the process is reversed with the application of the force on the semi-rigid centralizer 10 being reversed to pull the centralizer 10 from the well. | A semi-rigid floating spring type centralizer for use in deviated, highly deviated or horizontal well bores, the centralizer comprising a cylindrical tubular housing having a plurality of floating centralizer springs retained thereon. | 4 |
FIELD OF THE INVENTION
This invention relates to a process for the isomerization of paraffins. The process involves contacting the paraffins with a catalyst at isomerization conditions. Crucial parameters of the process are the injection of a nitrogen containing compound and raising the operating temperature by about 20° C. to about 150° C.
BACKGROUND OF THE INVENTION
Paraffinic oils containing C 10+ (ten carbons or higher) compounds find various uses as lubricating oils, heating oils, jet fuels, etc. One requirement of these oils is that they have a low viscosity or pour point at low temperatures. However, these paraffin mixtures usually contain straight chain or slightly branched paraffins which are waxes at lower temperatures which result in the paraffin mixture having a high pour point or viscosity at the lower temperatures. In order to remove these waxes, various processes are used to dewax the paraffin feed. Dewaxing processes include catalytic cracking where the long chain paraffins are cracked to smaller chain paraffins and isomerization where the straight chained paraffins are isomerized to branched paraffins.
Dewaxing by isomerization is disclosed in U.S. Pat. No. 4,419,220. The isomerization catalyst which is used is a zeolite beta having a silica: alumina ratio of at least 30:1 and having a hydrogenation component such as platinum. It is further disclosed that lower temperatures favor isomerization over cracking and therefore, lower temperatures are preferred. The '220 patent also discloses a preliminary hydrotreating step to remove nitrogen and sulfur compounds in order to improve catalyst performance and permit operation at lower temperatures.
As the '220 patent discloses, a bifunctional catalyst is used in order to achieve high isomerization selectivity. The two functions are hydrogenation and isomerization. Hydrogenation (and dehydrogenation) is carried out by the metal function, e.g., platinum, palladium, nickel, etc., while isomerization is carried out by the acid function, e.g., zeolites, Si--Al, etc.
The specific steps in paraffin isomerization are as follows. First, the paraffin is dehydrogenated on the metal function to give an olefin. The olefin reacts with the acid function to give a n-carbenium ion which is isomerized to an iso-carbenium ion. Next the iso-carbenium ion will be converted to an iso-olefin followed by hydrogenation to an iso-paraffin. Additionally, the iso-paraffins can be cracked on the acid sites to give low molecular weight paraffins and low molecular weight carbenium ions which will in turn be hydrogenated to light paraffins. Competition between hydrogenation and cracking explains product distribution. To maintain the high isomerization activity the hydrogenation function of the catalyst should be high enough to convert the intermediate carbenium ions to iso-paraffins and prevent their cracking. In the presence of sulfur hydrogenation activity will be suppressed owing to formation of metal sulfides with low hydrogenation activity and thus cracking will dominate resulting in low isomerization selectivity and the formation of light paraffins. Accordingly, there is a need for an isomerization catalyst/process which can function well in the presence of sulfur.
Applicant has found a solution to this problem which involves injection of a nitrogen containing compound, e.g., ammonia, into the isomerization reactor and simultaneously increasing the temperature by about 20° C. to about 150° C.
There are several references which disclose the use of nitrogen compounds in refining processes. For example, U.S. Pat. No. 5,419,830 discloses the use of ammonia to control the temperature in the reactor and prevent temperature runaway. U.S. Pat. No. 4,158,676 discloses the isomerization of monocyclic methyl-substituted aromatic hydrocarbon compounds in which nitrogen containing compounds are injected. U.S. Pat. No. 5,275,720 describes a two stage hydrocracking process in which ammonia is injected in the first stage to increase catalyst cracking activity.
In contrast to these references, applicant's process combines the injection of a nitrogen containing compound with an increase in the operating temperature. Increasing the temperature is contrary to the teachings in the art which state that lower temperatures favor isomerization. This results in improved selectivity and sulfur tolerance.
SUMMARY OF THE INVENTION
As stated the present invention relates to an improved isomerization process. Accordingly one embodiment of the invention is a process for the isomerization of paraffins in the presence of sulfur compounds, comprising contacting the paraffins with a catalyst at a temperature of about 20° C. to about 150° C. higher than the normal temperature of about 250° C. to about 500° C., a pressure of about atmospheric to about 25,000 kPa, a hydrogen to paraffin volume ratio of about 200 to about 4,000 std m 3 /m 3 , a space velocity of about 0.1 to about 10 hr -1 and injecting from about 5 to about 50,000 ppm nitrogen present as a nitrogen containing compound thereby improving the selectivity and sulfur resistance of the catalyst.
This and other objects and embodiments will become clear after a more detailed description of the invention.
DETAILED DESCRIPTION OF THE INVENTION
One essential feature of the present invention is an isomerization catalyst. The catalyst comprises a refractory inorganic oxide, the oxide having dispersed thereon a hydrogenation component and, optionally, a binder. The refractory inorganic oxide is selected from, but not limited to, SAPO and MeAPSO molecular sieves, zeolites, especially MFI, and amorphous Si--Al.
SAPO is an acronym for a silicoaluminophosphate molecular sieve. The preparation and characterization of SAPO's is described in U.S. Pat. No. 4,440,871, which is incorporated by reference. The SAPO molecular sieves are identified by a numbering system which refers to a specific structure, e.g., SAPO-5, SAPO-11, etc., which is also described in the '871 patent. MeAPSO is an acronym for metal aluminumsilicophosphate molecular sieves where Me is selected from the group consisting of magnesium, manganese, cobalt, iron, zinc, and mixtures thereof. MeAPSOs are described in U.S. Pat. No. 4,793,984 which is incorporated by reference. The specific molecular sieves are also described in the following patents: MgAPSO or MAPSO--U.S. Pat. No. 4,758,419. MnAPSO--U.S. Pat. No. 4,686,092; CoAPSO--U.S. Pat. No. 4,744,970; FeAPSO--U.S. Pat. No. 4,683,217 and ZnAPSO--U.S. Pat. No. 4,935,216, all of which are incorporated by reference. A preferred MeAPSO support is MAPSO (M=Mg) and a preferred MAPSO is MAPSO-31 where 31 means a MAPSO molecular sieve having structure type 31. This numbering system is also described in the above incorporated patents.
Among the zeolites which can be used are MFI and ferrierite. MFI is the International Zeolite Association designation for ZSM-5 or silicalite. ZSM-5 is described in U.S. Pat. No. 3,702,886 which is incorporated by reference.
Silicalite is described in U.S. Pat. Nos. 4,061,724 and 4,073,865 which are incorporated by reference. ZSM-5 is represented by the empirical formula:
(0.9±0.2)M.sub.2 O/n: Al.sub.2 O.sub.3 :xSiO.sub.2
where M is an alkali metal cation and x is at least 5. For use in the present invention, x is greater than 50. That is the SiO 2 /Al 2 O 3 ratio is greater than 50 or the Si/Al ratio is greater than 100.
Another oxide which can be used is an amorphous silica-alumina (Si--Al). This amorphous material is not a physical mixture of silica and alumina but is an acidic and amorphous material that has been cogelled or coprecipitated. This term and details regarding the preparation can be found in U.S. Pat. Nos. 3,909,450; 3,274,124 and 4,988,659 which are incorporated by reference.
Any of the oxides enumerated above can be formed into any desired shapes such as pills, cakes, extrudates, powders, granules, spheres, etc. and they may be utilized in any particular size. The oxide is formed into the particular shape by means well known in the art. In making the various shapes, it may be necessary to mix the oxide with a binder. Examples of binders which can be used include but are not limited to alumina, silica, silica-alumina (see above) and mixtures thereof. Usually the oxide and binder are mixed along with a peptizing agent such as HCl, HNO 3 , KOH, etc. to form a dough. This dough is extruded through a suitably shaped and sized die to form extrudate particles, which are dried and calcined. Calcination is normally carried out at a temperature of about 260° C. to about 650° C. for a period of about 0.5 to about 2 hours. The amount of binder which is present in the composite can vary from about 10 to about 90 wt. % of the composite and preferably from about 30 to about 70 wt. %. Additionally, the oxide support can be formed into spheres using the well known oil drop method. This method is preferred for the preparation of amorphous silica-alumina spheres and is described in U.S. Pat. No. 4,497,704 which is incorporated by reference. Note that in this case no binder is used.
Another essential element of the catalyst of this invention is a hydrogenation component which is a Group VIII metal. The Group VIII metals which can be used include platinum, palladium, rhodium, iridium, osmium, ruthenium, iron, cobalt, nickel and mixtures thereof. Preferred Group VIII metals are platinum and palladium. The Group VIII metal is dispersed onto the support by means well known in the art such as spray impregnation or evaporative impregnation. Both spray or evaporative impregnation use a solution containing a decomposable compound of the desired noble metal. By decomposable is meant that upon heating the compound decomposes to provide the noble metal or noble metal oxide. Examples of decomposable compounds which can be used include chloroplatinic acid, palladic acid, chloroiridic acid, rhodium trichloride, rutherium tetrachloride, osmium trichloride, rhodium nitrate, ammonium chloroplatinate, platinum tetrachloride hydrate, palladium chloride, palladium nitrate, tetraamine platinum chloride, tetraamminepalladium (II) chloride, iron chloride, cobalt chloride, nickel chloride, iron nitrate, cobalt nitrate and nickel nitrate. The solvent which is used to prepare the solution is usually water although organic solvents such as alcohols, dimethyl formamide (DMF), dimethylsulfoxide (DMSO), tetrahydrofuran (THF) and amines, e.g., pyridine, can be used. Spray impregnation involves taking a small volume of the solution and spraying it over the support while the support is moving. When the spraying is over, the wetted support can be transferred to other apparatus for drying or finishing steps.
One particular method of evaporative impregnation involves the use of a steam-jacketed rotary dryer. In this method the support is immersed in the impregnating solution which has been placed in the dryer and the support is tumbled by the rotating motion of the dryer. Evaporation of the solution in contact with the tumbling support is expedited by applying steam to the dryer jacket. The impregnated support is then dried at a temperature of about 60° C. to about 300° C. and then calcined at a temperature of about 300° C. to about 850° C. for a time of about 30 minutes to about 8 hours to give the calcined catalyst.
The amount of Group VIII metal deposited onto the oxide can vary considerably from about 0.05 to about 10 wt. % of the catalyst. Specifically, when the noble metal is platinum, the amount dispersed on the catalyst varies from about 0.2 to about 1.0 wt. %.
The catalyst described above is now used to isomerize long chained paraffins. A variety of feedstocks can be treated using the catalyst described above including reduced crudes, vacuum tower residue, cycle oils, FCC tower bottoms, gas oils, vacuum gas oils and other heavy oils. The feed will normally be a C 10 + feedstock since lighter oils will usually be free of significant quantities of waxy components. However, the process is particularly useful with waxy distillate stocks such as gas oils, kerosenes, jet fuels, lubricating oil stocks, heating oils and other distillate fractions whose pour point and viscosity need to be maintained within certain specification limits. Lubricating oil stocks will generally boil at about 230° C. (450° F.), more usually above 315° C. (600° F.). Hydrocracked stocks are a convenient source of stocks of this kind and also of other distillate fractions since they normally contain significant amounts of waxy n-paraffins which have been produced by the removal of polycyclic aromatics. The feedstock for the present process will normally be a C 10 + feedstock and more specifically one containing C 10 to C 40 hydrocarbons. These feedstocks will contain paraffins, olefins, naphthenes, aromatics and heterocyclic compounds, with a substantial proportion of higher molecular weight n-paraffins and slightly branched paraffins which contribute to the waxy nature of the feedstock. The feedstock will also contain some amount of sulfur, ranging from a few parts per million (ppm) to several thousand ppm.
The feedstock is contacted with the catalyst in a reactor in which the catalyst is present as stationary bed, a fluidized bed or any other type of catalyst bed. Usually the contacting is carried out at a temperature of about 250° C. to about 500° C., but in the instant invention, the temperature is raised from about 20° C. to about 150° C. above these "normal" or "usual" temperatures, which is typical for hydrotreated feedstocks containing no, or substantially no, sulfur. That is, the operating temperature is determined by the type of feedstock which is used, the relative activity of the catalyst, the amount of sulfur in the feed, pressure, H 2 /HC ratio, etc. Once this temperature is determined, the temperature is raised from about 20° C. to about 150° C. depending on the amount of nitrogen compound added and the relative activity of the catalyst. The greater the amount of nitrogen compound, the higher the temperature must be raised.
Pressures range from atmospheric to about 25,000 kPa (3,600 psig) and preferably from about 4,000 to about 10,000 kPa (565 to 1,435 psig). Liquid Hourly Space Velocity (LHSV) ranges from about 0.1 to about 10 hr -1 and preferably from about 0.2 to about 5 hr -1 . Hydrogen is also added in a hydrogen: feedstock volume ratio of about 200 to about 4,000 std.m 3 /m 3 (1,125 to 22,470 SCF/bbl) preferably 600 to 2,000 std.m 3 /m 3 (3,370 to 11,235 SCF/bbl).
The instant process also requires the injection of a basic nitrogen containing compound into the reactor. The compounds that can be used include ammonia and organic nitrogen containing compounds such as alkyl amines, aromatic amines, heterocyclic nitrogen-containing compounds, amides, etc. Specifically the alkyl amines can contain 1 to 30 carbon atoms and preferably 1 to 8 carbon atoms. Examples include methyl amine, tertiary butyl amine, ethyl amine, ethyl butylamine, tripropylamine, triethanolamine, cyclohexylamine, di-n-propylamine, neopentylamine, di-n-pentylamine, etc. Aromatic amines with 6 to 50 carbon atoms are within the invention and include aniline, diphenylamine, N-methyl-N-ethylamine, p-toluidine, p-phenylene-diamine, N-methylaniline, dimethylaniline, etc. Heterocyclic nitrogen compounds include pyridine, pyrolidine, quinoline, piperidine, piperazine, pyrrole, pyrellidine, etc. Amides include dimethyl formade, N-phenyl-acetamide, N-methyl-N-ethylbenzamide, etc.
The nitrogen containing compound can be cofed with the paraffin feedstock or can be directly injected into the reactor. Injection into the reactor can be done using one injection port or multi-injection ports. Regardless of which method is used to introduce the nitrogen containing compound, the amount of nitrogen containing compound which is introduced is that amount which give from about 5 to about 50,000 ppm and preferably from about 10 ppm to about 1,000 ppm nitrogen.
In order to more fully illustrate the invention, the following examples are set forth. It is to be understood that the examples are not intended as an undue limitation on the broad scope of the invention as set forth in the appended claims.
EXAMPLE 1
MAPSO-31 was prepared according to U.S. Pat. No. 4,758,419. Platinum was dispersed onto the MAPSO-31 support as follows. An aqueous solution containing sufficient tetraamineplatinum chloride to give 0.4 wt. % Pt on the final catalyst was used to ion exchange platinum onto MAPSO-31 by contacting the solution with the MAPSO-31 powder for a time of about 4 hours at a temperature of about 70° C. The ion exchanged powder was mixed with peptized alumina in a ratio of 80:20 (MAPSO-31:Al 2 O 3 ), the resultant dough was extruded and dried at 120° C. for 8 hours. Finally, the dried material was calcined in air at 500° C. for 4 hours. The catalyst was identified as catalyst A.
EXAMPLE2
SAPO-11 was prepared according to the procedure in U.S. Pat. No. 4,440,871. The SAPO-11 was mixed with alumina (60:40 wt. ratio), water and nitric acid, mixed and then extruded. The wet extrudates were dried at 100° C. for 24 hours and calcined in air at 600° C. for 3 hours to give the SAPO-11/Al 2 O 3 support.
The SAPO-11/Al 2 O 3 support was impregnated with an aqueous solution containing sufficient chloroplatinic acid to give 0.4 wt. % Pt (with respect to alumina) as follows. In a rotary evaporator the support and solution were mixed in a 1:1 volume ratio, rotated at room temperature for one hour and then heated with steam to evaporate the excess water. The impregnated support was dried at 120° C. and then calcined at 500° C. for 4 hours. This catalyst was identified as catalyst B.
EXAMPLE 3
A spherical support of cogelled silica-alumina with 35% SiO 2 and 65% Al 2 O 3 was prepared as in U.S. Pat. No. 4,497,704. The spherical support was impregnated with 0.4 wt. % platinum as in Example 2. This catalyst was identified as catalyst C.
EXAMPLE 4
The catalysts described above were tested for C-10 hydroisomerization as follows. A sample containing 5 grams of catalyst and 5 g of quartz were mixed and placed in a reactor. Next, the catalyst was reduced in situ in one of three ways. If the test involved a clean feed, i.e., no sulfur or nitrogen, then the catalyst was reduced using a H 2 stream at 400° C. for 4 hours. If the test involved adding sulfur to the feedstream, then the catalyst was pretreated using a H 2 /H 2 S(85/f15) stream at 400° C. for 4 hours. Finally, if the test involved using both sulfur and nitrogen, then the catalyst was first reduced using a H 2 stream containing 1,000 ppm NH 3 and then this stream was replaced with a H 2 stream containing 1,000 ppm of H 2 S at 400° C. for 4 hours.
A feed containing n-C 10 plus hydrogen at a ratio of H 2 /hydrocarbon of 1000 SCFB was downflowed through the catalyst at a LHSV of 25 g/hr and a pressure of 3448 kpag (500 psig). The reactor was ramped up to a certain temperature and lined out at that temperature for 5 hours. At that point the effluent was analyzed by gas chromatography to determine the percent of n-C 10 . converted, i.e., disappearance of n-C 10 and the selectivity to I-C 10 . Any component having a carbon number less than 10 is a cracked component and undesirable.
When sulfur was added, it was added at 1000 ppm as H 2 S and mixed with the hydrogen. In the case where nitrogen was added, it was added as tertiary butyl amine (TBA) present in the n-C 10 feed. The amount of TBA added was such as to give 770 ppm N in the feed. The results of this test are presented in the Table. What is presented is the temperature needed to reach 50% conversion and selectivity to iso-C 10 at that temperature.
TABLE______________________________________Effect of Nitrogen and Sulfur on Catalyst Selectivity Temp (° C.) at Selectivity (%) H.sub.2 S NCatalyst I.D. 50% Conv. to iso-C.sub.10 (ppm) (ppm)______________________________________A 330 82 0 0A 378 53 1000 0A 422 75 0 770A 433 84 1000 770B 328 97 0 0B 397 97 1000 770C 384 95 0 0C 442 95 1000 770______________________________________
The results in the Table show that the presence of sulfur alone increases the temperature needed to 50% conversion and severely decreases the selectivity to iso-C 10 . The presence of nitrogen alone also decreases selectivity but not as much as sulfur alone. However, by introducing nitrogen when sulfur is present, one obtains the same selectivity versus the case where neither is present, but at a higher temperature. | A paraffin isomerization process is described and claimed. The process involves contacting the paraffins with an isomerization catalyst at isomerization conditions. Additionally, the process requires the injection of a nitrogen containing compound such as an amine, e.g., t-butylamine, and raising the operating temperature by about 20° C. to about 150° C. The effect of these modifications is to provide improved selectivity and sulfur resistance to the catalyst. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to multiphase direct current power supplies and refers more particularly to such power supplies wherein the power supply secondary circuit impedance is reduced through a Y connection of the primary circuit transformer primary windings whereby current through the secondary circuit of the power supply is split between multiple diode paths.
2. Description of the Prior Art
In the past, large three-phase direct current power supplies for example might have an open circuit, that is zero current output voltage, of approximately 19 volts. At 100,000 amperes, such output voltage may drop to approximately 8 volts. Thus, approximately 11 volts may be dropped inside such power supply.
In an effort to improve the efficiency of such power supplies, and on investigation it has been found that the power supply transformers have a 7% impedance factor. That is, the voltage output of the transformers drops approximately 7% from a no-load to a full-load condition. Using this factor, the transformers themselves contribute approximately 1.5 volts to the total internal voltage drop of such power supplies.
It is usual in such power supplies to have six sets of ten diodes each in parallel in the power supply secondary circuit. Such a circuit is referred to as a 6-phase star. With the usual connection of prior power supply circuits, one set of ten diodes is conducting the full output current at any time. Therefore, each diode of a set when conducting may conduct 10,000 amperes. Manufacturer's information for such diodes indicates that the voltage drop across such diodes increases from approximately 0.5 volts at low currents to 1.5 volts at 10,000 amps. Therefore, the voltage drop through the diodes accounts for approximately 1.5 volts of the total internal voltage drop of such three-phase direct current power supplies.
With such prior power supplies, the analysis of the copper cross section area of the internal buses of the power supply indicates that the voltage drop due to the resistance of the copper is normally less than 0.5 volts.
Thus, the voltage drop through the transformers of such power supplies, and the copper and diodes thereof, account for about 31/2 volts of the total 11 volt drop in such power supplies. Most of the remaining voltage drop comes from inductance. That is, the conductors carrying current from the transformers through the diodes to the output of the power supply have inductance. Since each diode set transitions from non-conducting to conducting, in the operation of the power supply, the inductance resists the flow of current.
Inductance in this area shows up as a non-unity power factor in the primary of the transformers. Additional open circuit transformer voltage is needed to overcome this inductance which results in a higher primary current demand for a given secondary current.
With reference to the prior art, connection of the primary circuit of three-phase direct current power supplies as considered above, areas are noted where power supply impedance may be improved.
Thus, due to the delta configuration of the transformer primary windings shown in FIG. 1, only one transformer winding at any instant of time is conducting. This means that only one set of diodes in the secondary circuit of the power supply will be conducting at any time. Therefore, the entire current of a power supply with transformer primary windings connected as shown in FIG. 1 has to flow through the impedance provided by one transformer, one diode set, and the associated conductors. Despite the fact that there are six possible current paths through the power supply, one through each diode set, there has been no use made of any possible parallel current paths to reduce the internal impedance of prior multiphase direct current power supplies.
SUMMARY OF THE INVENTION
In accordance with the invention, the primary circuit of a multiphase direct current power supply is connected with the primary windings of the transformers thereof in a Y configuration. Contactors are placed between the inner ends of the transformer primary windings or in series with the incoming three-phase power line so that all current flow is through two transformer primaries in series at all times. As a result, current is flowing in two of the secondary circuits simultaneously, and therefore through two sets of diodes and associated circuitry in parallel, thereby reducing most impedances by one half, thus allowing more efficient operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of the primary circuit of a prior art three-phase direct current power supply.
FIG. 2 is a schematic diagram of the primary circuit of one modification of a three-phase direct current power supply constructed in accordance with the invention.
FIG. 3 is a schematic diagram of the primary circuit of another modification of a three-phase direct current power supply constructed in accordance with the invention.
FIG. 4 is a schematic diagram of the transformer primary windings of the primary circuit and the secondary circuit of a three-phase direct current power supply as used either with the prior art primary circuit of FIG. 1 or with the improved primary circuit of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown best in FIG. 2, the primary circuit 10 of a three-phase direct current power supply generally indicated 12, which power supply 12 includes the secondary circuit of FIG. 4, takes advantage of possible parallel current paths in a three-phase direct current power supply, and results in efficiency improvements of such power supply due to lower internal impedance.
In the primary circuit 10 of the power supply 12, as shown in FIG. 2, the three transformer primary windings 14,16 and 18 are connected at their inner ends in a Y configuration through contactors 20, 22 and 24. At their outer ends, the transformer primary windings are connected to the usual incoming energy phase lines 26,28 and 30 of a multiphase power line.
The same elements are shown designated by the same numbers in FIG. 1 in the configuration of the prior art.
In the configuration of FIG. 2, of the invention, any current path, that is, from line 26 to 28, line 28 to 30, or line 30 to 26, must be through two transformer primary windings.
Thus, in the secondary circuit 25 of the power supply 12, as shown in FIG. 4, there are always two diodes sets conducting at any instant of time, with each one conducting one-half of the total output current of the power supply.
As shown in FIG. 4, the secondary windings of the power supply transformers 32,34 and 36 correspond to transformer primary windings 14,16 and 18. The transformer secondary winding 32 is broken into part 38 and part 40 feeding diode sets 42 and 44, respectively. Filter resistance 46 and capacitance 48, respectively, are associated with the diode set 42. Resistance 50 and capacitance 52 are associated with the diode set 44. Similarly, transformer secondary winding 34 is broken up into two separate parts 54 and 56. The part 54 is associated with its diode set 58 and resistance and capacitance 60 and 62, respectively, while the part 56 of the transformer secondary winding 34 is associated with the diode set 64 and resistance 66 and capacitance 68. Diode set 70 and resistance and capacitance 72 and 74 are associated with part 76 of the transformer secondary winding 36, while diode set 78 and resistance 80 and capacitance 82 are associated with the part 84 of the transformer secondary winding 36. As shown in FIG. 4, the multiple sets of diodes are connected together in parallel to provide a substantially direct current output over the conductors 86 and 88.
The effect of the connection of the transformer primary windings 14,16 and 18 as shown in FIG. 2 is to lower the internal impedance of the power supply 12 by splitting the current flow through two parallel paths with identical impedance characteristics in the secondary power supply circuit 25 shown in FIG. 4. Thus, the impedance due to the resistance and inductance of the internal conductors of the power supply between the transformers and the output is reduced by substantially one-half.
In addition, the maximum amount of current obtainable from the power supply 12 without damaging the diodes in the secondary circuit is increased. Because the output current is always shared through two diode groups, the peak current through each diode is reduced by one-half, as compared to the power supply having a primary circuit with the configuration of FIG. 1. This results in a 30% increase in allowable average current through each diode due to a lower peak to average ratio. In other words, the number of diodes needed for a given output current is reduced by 30%.
Another advantage of the power supply primary circuit of FIG. 2 is that the power factor of the direct current power supply is improved. Because each diode set and its associated buses are conducting over a maximum of 120° phase angle of a 60 Hz. three-phase input signal rather than a maximum 60° as would be the case with the primary circuit 10 in the FIG. 1 configuration, the inductive effects of the internal buses in the power supply 12 are reduced. This shows up in the primary circuit 10 of the power supply 12 as an improved power factor. The improved power factor reduces the power line current which reduces the K.V.A. demand of the power supply for a given output current. The reduced K.V.A. allows the use of smaller transformers for a given output current.
Another effect, observed experimentally, is that the power supply of the invention operates quieter and with less vibration than the prior art power supply, as disclosed above. It is hypothesized that such operation is due to the 50% reduction in peak current through internal buses. This lessening of vibration makes fatique failure of brazed junctions in the copper buses less likely.
Improvements in efficiency are largest when the load impedance connected to the direct current power supply is low, that is, 25 microhms or less. As the load impedance rises, the internal impedance of the power supply becomes a smaller fraction of the total circuit impedance and the overall system efficiently improvement becomes less. Inductive impedance in the secondary load has the same effect on the efficiency improvement as resistance.
The reduced vibration and increased allowable average diode current occur regardless of load impedance. That is to say, with the primary power supply circuit of FIG. 2, a direct current power supply can be made to deliver 30% more output current than with the configuration of FIG. 1 without exceeding the average current rating of the diodes.
While one embodiment of the present invention has been considered in detail, it will be understood that other embodiments and modifications are contemplated by the Inventor.
Thus, for example, in the modification of the invention shown in FIG. 3, wherein similar components are given the same reference numbers, the contactors are directly connected to and are in series with the separate phase lines of the incoming power line, the three primary windings of the welding transformers are connected in a simple wye arrangement.
The operation and advantages of the FIG. 3 modification of the invention are substantially the same as the operation and advantages of the FIG. 2 modification of the invention.
It is the intention to include all embodiments and modifications of the invention as are defined by the appended claims within the scope of the invention. | Structure for and method of eliminating impedance in multiphase direct current power supplies comprising connecting transformer primary windings in Y configuration with contactor structure, whereby multiple impedance paths through transformer secondary circuits are provided. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a method and a system for diagnosing the operating state of an assisted starting mode of a motor vehicle.
Currently, certain motor vehicles are fitted with an assisted starting mode which consists in managing the parking brake automatically when the vehicle is started. The parking brake is a braking system that supplements the brakes actuated by the brake pedal. This parking brake is usually used to immobilize the vehicle when the latter is stationary, and can also be used to carry out emergency braking when the vehicle is moving.
Automatic management of the parking brake makes it possible, amongst other things, to help the driver to carry out a starting on a slope, also called a “hill start”. The principle of the hill start is to release the brakes on the non-drive wheels when the torque transmitted by the engine to the drive wheels is sufficient to compensate for the effect of the slope.
One of the problems encountered when automatic starting management is used is that this management may, in certain conditions, not request the release of the brakes thus refusing the assisted start.
It is therefore useful to be able to ascertain the conditions that have led to such a refusal for the purpose of diagnosing the possible faults of the automatic starting management system. Also, it may be worthwhile to save the traces of these refusal conditions, but the saves of these conditions may be numerous and occupy considerable memory space. The question is therefore to fit the vehicles with appropriate means for economizing on the memory space used by the saving means.
It is possible to cite for example the British patent application GB 2 376 990 which describes a parking-brake control system in which the parking brake is released when the vehicle is driven in a positive movement and the clutch pedal reaches a satisfactory position, but this document does not describe a means for diagnosing the conditions of refusal of an assisted start.
It is possible to cite also the British patent application GB 2 342 967 which discloses a parking-brake control device in which said brake is released when the braking torque applied to the wheels is below a certain threshold. Moreover, it is possible to cite the French patent application FR 2 828 450 filed in the name of the applicant which describes an assisted hill start device and the French patent application FR 2 841 199, also filed in the name of the applicant, which discloses a device for the automatic release of the automatic parking brake when starting. But these documents also do not disclose a means for diagnosing the conditions of refusal of an assisted start.
SUMMARY OF THE INVENTION
One of the objects of the invention is therefore to provide a system and a method for diagnosing the conditions of refusal of an assisted start by an automatic management mode.
Another object of the invention is to trace the history of these conditions with an optimized and the smallest possible memory occupancy.
The subject of the invention is therefore a system for diagnosing the operating state of an assisted starting mode of a motor vehicle fitted with a drive engine and a gearbox, comprising a means for determining an item of information on the engine rotation speed, an item of information on the position of the accelerator pedal of the vehicle, an item of information on the position of the gearbox and an item of information on the torque transmitted to the wheels.
This system comprises a detection means for generating a signal of malfunction of the assisted start based on said items of information received, several encoding means for generating a monitoring signal for each determined item of information received, and a memory for saving said monitoring signals.
Specifically, with the aid of a means for detecting and saving the conditions of refusal of an assisted start, it is possible to diagnose the causes of malfunction of the assisted start. Also with the aid of a means for encoding the selected items of information that describe in the best way possible the operating conditions of the assisted start, it is possible to greatly reduce the memory space occupied by these items of information.
According to another embodiment, when the assisted start is in operation, each encoding means is capable of modifying said monitoring signal by allocating thereto a value corresponding to distinct states of the determined item of information received.
By using a single monitoring variable per selected item of information, the memory occupancy is reduced because not all the values of the selected item of information throughout the assisted start are recorded, but a single value dependent on the operating conditions of the assisted start is recorded only when an assisted start refusal is detected. Also, each encoding means allocates a value to a monitoring variable; this value corresponds to a particular state of the determined item of information. These distinct states therefore correspond to operating conditions of the assisted start.
According to yet another embodiment, each encoding means comprises a comparison module for generating a satisfactory condition signal based on the comparison between the determined item of information received and a threshold.
By providing a simple means for encoding the information items received with the aid of a comparison, it is possible to provide a small-sized means suitable for the needs for saving space in motor vehicles, and this also makes it possible to make the encoding system reliable by the use of a small number of computing modules which restricts the failures.
According to another embodiment, the detection means generates an encoding activation signal and a signal validity signal for each determined item of information received, and the distinct states of each item of information received are determined based on the satisfactory condition signal, on said signal validity signal and on said encoding activation signal.
Also added is a test of validity of the signals in order to ensure the reliability of the whole system. Equally, with the aid of three signals: a validity signal, an assisted start activation signal and a satisfactory condition signal, it is possible to create distinct states of operating condition.
According to another aspect, the subject of the invention is a method for diagnosing the operating state of an assisted starting mode of a motor vehicle, wherein an item of information on the rotation speed of an engine of the vehicle, an item of information on the position of the accelerator pedal of the vehicle, an item of information on the position of the gearbox and an item of information on the torque transmitted to the wheels are determined.
In this method, a malfunction of the assisted start is detected based on said items of information received, each determined item of information received is encoded with the aid of a monitoring signal, and said monitoring signals are saved.
According to another embodiment, when the assisted start is in operation, each item of information received is encoded by the modification of said monitoring signal by allocating thereto a value corresponding to distinct states of the determined item of information received.
According to yet another embodiment, a satisfactory condition signal is generated based on the comparison between the determined item of information received and a threshold before each item of information received is encoded.
According to another embodiment, an encoding activation signal and a signal validity signal are generated for each determined item of information received and the distinct states of each item of information received are determined based on the satisfactory condition signal, on said validity signal and on said encoding activation signal.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the invention will appear on reading the following description given only as a nonlimiting example, and made with reference to the appended drawings in which:
FIG. 1 is a schematic view of a diagnostic system according to the invention; and
FIG. 2 is a schematic view of an embodiment of a module for detecting an assisted-start refusal; and
FIGS. 3 a , 3 b , 3 c and 3 d show a flow chart illustrating the main phases of a method for detecting an assisted-start refusal; and
FIG. 4 is a schematic view of a general embodiment of a module for encoding an item of diagnostic information; and
FIG. 5 is a schematic view of an embodiment of a module for encoding items of diagnostic information; and
FIGS. 6 a , 6 b , 6 c and 6 d show a flow chart illustrating the main phases of a method for encoding an item of diagnostic information.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 represents a schematic view of a system for diagnosing the operating state of an assisted-start mode of a motor vehicle. The diagnostic system is essentially hosted within an electronic control unit (ECU) 2 .
The ECU 2 comprises an input module 3 , an assisted-start management module 4 , a detection module 5 , an encoding module 6 and a saving module 7 . The operating principle of the diagnostic system consists in detecting, by means of the detection module 5 , an assisted-start refusal, in activating encoding of the useful items of information with the aid of the encoding module 6 and in saving said items of encoded information and certain other items of information of the system by means of the saving module 7 in order to trace the history of the conditions of assisted-start refusal.
The input module 3 makes it possible to transmit useful items of information concerning the state of the vehicle to the various modules 5 , 6 and 7 of the ECU 2 , such as for example the speed of the vehicle and the rotation speed of the engine. These items of information can be measurements taken with the aid of sensors or be estimates made by computing modules of the ECU 2 , not shown in the figure.
The assisted-start management module 4 hosts an algorithm controlling a parking brake 1 by sending application or release commands transmitted via the connection 8 to the parking brake 1 . This module 4 also transmits signals to the detection module 5 , which signals are transmitted via the connection 9 , and to the encoding module 6 , transmitted via the connection 10 .
The detection module 5 detects an assisted-start refusal based on items of information originating from the management module 4 and based on items of information originating from the input module 3 and transmitted via the connection 11 . This detection module 5 activates the encoding of the items of diagnostic information by sending signals, transmitted via the connection 12 , to the encoding module 6 . The module 5 also makes it possible to activate the saving of the items of information by sending signals, transmitted via the connection 13 , to the saving module 7 .
The encoding module 6 receives the items of information that are useful for the diagnosis to be encoded from the input module 3 and transmitted via the connection 14 . The results thus encoded are then transmitted, via the connection 15 , from the encoding module 6 to the saving module 7 .
The saving module 7 records the items of information received from the detection module 5 , the encoding module 6 and from the input module 3 transmitted respectively via the connections 13 , 15 and 16 . This module 7 is capable of recording the received items of information permanently in a non-volatile memory which may be, for example, of the EEPROM or “Electrically Erasable Programmable Read Only Memory” type.
Moreover, the connections 8 to 16 are capable of transferring several different signals from one module to the other of the ECU 2 .
FIG. 2 represents a schematic view of an embodiment of a module 5 for detecting an assisted-start refusal. Also shown in FIG. 2 are elements previously described in FIG. 1 .
The module 5 comprises a detection-management module 20 and a module 21 for testing the validity of signals.
The detection-management module 20 makes it possible to apply a method for detecting an assisted-start refusal which will be described later with reference to FIGS. 3 a to 3 d . This module 20 receives input signals RDA_DetActif and DA_Actif, originating from the assisted-start management module 4 and transmitted respectively via the connections 22 and 23 .
RDA_DetActif: a Boolean signal which is:
0 if the detection of an assisted-start refusal is disabled 1 if the detection of an assisted-start refusal is enabled
DA_Actif: a Boolean signal which is:
0 if the assisted start is disabled 1 if the assisted start is enabled.
The signal RDA_DetActif is usually equal to 1 for enabling a detection of a refusal when the assisted start is enabled. But when the parking brake 1 is released or when the driver activates a command to carry out a manual start without assistance, the signal RDA_DetActif then has the value 0.
The module 20 also receives input signals EtatMoteur, Vvéh, RotationMoteur, AccPos, BV_Pos, CoupleRoues, Cmde_Desserrage and Cmde_ArretMoteur originating from the input module 3 and transmitted via the connections 24 to 31 respectively.
EtatMoteur: State of the engine which is:
0 if the engine is stopped 1 if the engine is driven 2 if the engine is considered to be running stand alone, that is to say if the engine has a sufficiently high rotation speed to drive itself
Vvéh: Item of information on the speed of the vehicle RotationMoteur: Item of information on the rotation speed of the engine AccPos: Item of information on the position of the accelerator pedal of the vehicle BV_Pos: Item of information on the position of the gearbox, or else, a Boolean signal which is:
0 if no gear is engaged (called “neutral position”) 1 if at least one gear is engaged (a forward gear or reverse gear)
CoupleRoues: Item of information on the torque transmitted to the wheels Cmde_Desserrage: a Boolean signal which is:
0 if there is no parking-brake release request 1 if there is a parking-brake release request
Cmde_ArrêtMoteur: a Boolean signal which is:
0 if the driver makes no request to stop the engine 1 if the driver requests to stop the engine.
The signal-validity test module 21 makes it possible to test whether certain received signals are valid. In FIG. 2 , only certain signals are tested. It will be possible advantageously to test the validity of all the input signals of the detection module 5 . The module 21 comprises test modules 32 to 37 to test the validity of the signals received respectively via the connections 38 to 43 . Each test module 32 to 37 is capable of generating a validity Boolean signal as a function of the test result. The module 21 generates the following signals:
Val_EtatMoteur: a Boolean signal of the validity of the EtatMoteur signal, which is:
0 if the EtatMoteur signal is not valid 1 if the EtatMoteur signal is valid
Val_Vvéh: a Boolean signal of the validity of the Vvéh signal, which is:
0 if the Vvéh signal is invalid 1 if the Vvéh signal is valid
Val_RotationMoteur: a Boolean signal of the validity of the RotationMoteur signal, which is:
0 if the RotationMoteur signal is invalid 1 if the RotationMoteur signal is valid
Val_AccPos: a Boolean signal of the validity of the AccPos signal, which is:
0 if the AccPos signal is invalid 1 if the AccPos signal is valid
For example: DA_Actif is 0 if Val_AccPos is 0; Val_BV_Pos: a Boolean signal of the validity of the BV_Pos signal, which is:
0 if the BV_Pos signal is invalid 1 if the BV_Pos signal is valid
Val_CoupleRoues: a Boolean signal of the validity of the CoupleRoues signal, which is:
0 if the CoupleRoues signal is invalid 1 if the CoupleRoues signal is valid.
It is possible to describe examples of tests of the validity of a signal that can be carried out by the test modules 32 to 37 . It is possible, for example, to describe the validity test of the Val_RotationMoteur signal. The RotationMoteur signal is considered invalid (that is to say that the Val_RotationMoteur signal is 0) if, for example, the value received by the module 34 is outside an acceptable range of variation, this range being between a minimum value and a maximum value. The RotationMoteur signal can also be considered invalid if it is not received by means of several frames transmitted from the input module 3 over the connection 40 for a certain time, for example for more than 1 second, or else if the RotationMoteur signal is inconsistent (for example: RotationMoteur>0 and the engine is also declared stopped EtatMoteur=0).
The module 20 also receives the abovementioned validity signals Val_EtatMoteur, Val_Vvéh, Val_RotationMoteur, Val_AccPos, Val_BV_Pos and Val_CoupleRoues originating from the module 21 and transmitted via the connections 44 to 49 respectively.
Based on a method for detecting an assisted-start refusal which can be implemented in the detection-management module 20 , the module 20 generates output signals as follows:
RDAType: type of assisted-start refusal and which is:
0 which means that the signal has been initialized 1 if the assisted-start refusal is of the first type “engine stall” 2 if the assisted-start refusal is of the second type “start with brake engaged”
RDA_Det: a Boolean signal which is:
0 if no assisted-start refusal is detected 1 if an assisted-start refusal is detected
Act_Codage: a Boolean signal which is:
0 if the encoding of the items of information is disabled 1 if the encoding of the items of information is enabled.
The RDA_Det signal makes it possible to signal to the encoding module 6 and to the saving module 7 that an assisted-start refusal has been detected. It is considered that an assisted-start refusal is a malfunction of the assisted start; the signal of a refusal is therefore equivalent to a signal of malfunction.
The Act_Codage signal makes it possible to enable the encoding of the diagnostic information items by activating the encoding module 6 . The RDAType signal makes it possible to distinguish the type of assisted-start refusal. It will be noted that there are two types of assisted-start refusal:
a first type “engine stall”: which describes a situation in which, during the assisted start, the engine stalls with the parking brake 1 engaged, without activation of the Cmde_Desserrage command to release said brake 1 , and with the driver desiring to start the vehicle; and a second type “start with brake engaged”: which describes a situation in which, during the assisted start, the vehicle starts with the parking brake 1 engaged and without activation of the Cmde_Desserrage command to release said brake 1 .
It is considered that the driver desires to start the vehicle if at least two conditions are met out of the following three:
the driver engages a gear ratio; the driver pushes down the accelerator pedal beyond a certain threshold, marked AccPosMin, of accelerator pedal position; the torque transmitted to the wheels is higher than a threshold, marked CoupleRouesMin.
Specifically, if the above three conditions are all met, an assisted start is carried out without refusal. Otherwise, an assisted-start refusal signal is enabled by means of the detection module 5 .
The RDAType and RDA_Det signals are transmitted respectively via the connections 50 and 51 to the saving module 7 . The RDA_Det, Act_Codage signals and the Val_RotationMoteur, Val_AccPos, Val_BV_Pos and Val_CoupleRoues validity signals are transmitted respectively via the connections 52 to 57 to the encoding module 6 .
FIGS. 3 a , 3 b , 3 c and 3 d show a flow chart illustrating the main phases of a method for detecting an assisted-start refusal. The method begins with an initial step 100 . This step is carried out as soon as an assisted start is enabled. After this initial step 100 , a comparison step 101 is carried out in which the validity of the Val_Vvéh and Val_EtatMoteur signals and the value of the Cmde_ArrêtMoteur signal are tested.
The following three conditions are considered:
the item of information on vehicle speed is valid (Val_Vvéh is 1) the item of information on the state of the engine is valid (Val_EtatMoteur is 1) the driver has not requested a stop of the engine (Cmde_ArrêtMoteur is 0).
If these three conditions are met, the method moves on to a waiting step 102 , otherwise the initial step 100 is carried out again. Moreover, it is possible to test the validity of these three conditions at any time during the execution of the method and, if one of these three conditions is not met, there is a return to the initial step 100 .
In the waiting step 102 , the following signals are first set to the zero value:
Act_Codage=0 RDA_Det=0 RDAType=0
Then, secondly, the comparison steps 103 and 104 are carried out to test whether the vehicle can be considered to be stationary.
In the comparison step 103 , the validity of the following three conditions is tested:
the item of information on the speed of the vehicle is invalid (Val_Vvéh is 0) the item of information on the state of the engine is invalid (Val_EtatMoteur is 0) the driver has requested a stop of the engine (Cmde_ArrêtMoteur is 1).
If at least one of these three conditions is met, there is a return to the initial step 100 , otherwise the following comparison step 104 is carried out.
In the comparison step 104 , the validity of the following two conditions is tested:
the item of information on the speed of the vehicle is zero (Vvéh is 0), and the engine is in the stand alone running state (EtatMoteur is 2) for a stop time t arrêt the detection of an assisted-start refusal is enabled (RDA_DetActif is 1).
If the two conditions are met, it is considered that the vehicle is stationary with the engine in the stand alone running state and a step 105 of preparing for starting is carried out, otherwise the waiting step 102 is carried out again.
During the step 105 of preparing for starting, the comparison steps 106 and 107 are carried out to test whether the conditions are met for considering that an assisted start is in progress. To do this, the comparison step 106 is carried out in which the validity of the following three conditions is tested:
the item of information on the speed of the vehicle is greater than or equal to the vehicle-speed threshold VvéhMin (Vvéh>=VvéhMin) the engine is no longer considered to be in a stand alone running state (EtatMoteur is not 2) the detection of an assisted-start refusal is disabled (RDA_DetActif is 0), for example if the parking brake 1 is not engaged.
If at least one of these three conditions is met, there is a return to the waiting step 102 , otherwise the following comparison step 107 is carried out. For example, if the engine is no longer in a stand alone running state or if the vehicle is accelerating so that the speed of the vehicle exceeds the speed threshold VvéhMin, there is a return to the waiting step 102 .
In the comparison step 107 , the validity tests of the following three conditions are carried out:
the item of vehicle-speed information is strictly below the vehicle-speed threshold VvéhMin (Vvéh<VvéhMin), and the engine is in the stand alone running state (EtatMoteur is 2) for the stop time t arrêt the detection of an assisted-start refusal is enabled (RDA_DetActif is 1) {at least one of the following four conditions is met:
condition 1: the driver is pressing down the accelerator pedal of the vehicle (AccPos>AccPosMin) and the item of information on the position of the accelerator pedal is valid (Val_AccPos is 1) condition 2: the driver engages a gear ratio (BV_Pos is 1) and the item of information on an engaged gear is valid (Val_BV_Pos is 1) condition 3: the torque transmitted to the wheels is greater than a minimum threshold (CoupleRoues>CoupleRouesMin) and the item of information on the torque transmitted to the wheels is valid (Val_CoupleRoues is 1) condition 4: the assisted start is disabled (DA_Actif is 0)}.
If these three conditions are met, a next step 108 of assisted start in progress is carried out and the step 105 of preparing for starting is again carried out in the contrary case.
In the step 108 , initially the following signals are modified in order to obtain:
Act_Codage=1 RDA_Det=0 RDAType=0
Then, secondly, the comparison steps 109 , 110 and 112 are carried out to detect whether an assisted-start refusal is enabled.
In the comparison step 109 , the validity of the following three conditions is tested:
the detection of an assisted-start refusal is disabled (RDA_DetActif is 0) the parking-brake release command is sent (Cmde_Desserrage is 1) the engine is not in a stand alone running state (EtatMoteur not 2) and there is no detection of an assisted-start refusal (RDA_Det is 0).
If at least one of these three conditions is met, there is a return to the waiting step 102 , otherwise the following comparison step 110 is carried out.
In the comparison step 110 , a validity test is carried out to detect whether an assisted-start refusal of the first type is enabled by carrying out the validity tests of the following five conditions:
the item of information on vehicle speed is strictly below the vehicle-speed threshold VvéhMin (Vvéh<VvéhMin) the engine is not in the stand alone running state (EtatMoteur not 2) the parking-brake release command is not sent (Cmde_Desserrage is 0) the detection of an assisted-start refusal is enabled (RDA_DetActif is 1) {at least one of the following three conditions is met:
condition 1: a gear ratio is engaged (BV_Pos is 1) and the item of information on the position of the gearbox is valid (Val_BV_Pos is 1) and the driver is pressing down the accelerator pedal of the vehicle (AccPos>AccPosMin) and the item of information on the position of the accelerator pedal is valid (Val_AccPos is 1) condition 2: the driver is pressing down the accelerator pedal of the vehicle (AccPos>AccPosMin) and the item of information on the position of the accelerator pedal is valid (Val_AccPos is 1) and the torque transmitted to the wheels is strictly greater than a minimum threshold (CoupleRoues>CoupleRouesMin) and the item of information on the torque transmitted to the wheels is valid (Val_CoupleRoues is 1) condition 3: a gear ratio is engaged (BV_Pos is 1) and the item of information on the position of the gearbox is valid (Val_BV_Pos is 1) and the torque transmitted to the wheels is strictly greater than a minimum threshold (CoupleRoues>CoupleRouesMin) and the item of information on the torque transmitted to the wheels is valid (Val_CoupleRoues is 1)}.
If these five conditions are met, it means that a refusal of the first type is detected; in this case, a step 111 of signaling a refusal of the first type is carried out, otherwise a comparison step 112 is carried out.
In the step 111 of signaling a refusal of the first type, the value of the RDAType signal is modified by allocating it the value 1 (RDAType is 1), which means that an assisted-start refusal of the first type has been detected. After this signaling step 111 , a step 115 of signaling a refusal of an assisted start is carried out which will be described later.
In the comparison step 112 , a validity test is carried out to detect whether an assisted-start refusal of the second type is enabled by carrying out the validity tests of the following three conditions:
the item of information on the vehicle speed is greater than or equal to the vehicle-speed threshold VvéhMin (Vvéh>=VvéhMin) the engine is in the stand alone running state (EtatMoteur is 2) the detection of an assisted-start refusal is enabled (RDA_DetActif is 1).
If these three conditions are met, it means that a refusal of the second type is detected; in this case, a step 113 of signaling a refusal of the second type is carried out, otherwise the step 108 of assisted start in progress is carried out.
In the step 113 of signaling a refusal of the second type, the value of the RDAType signal is modified by allocating it the value 2 (RDAType is 2), which means that an assisted-start refusal of the second type has been detected. After this signaling step 113 , the step 115 of signaling an assisted-start refusal is carried out.
In the step 115 of signaling an assisted-start refusal, the RDA_Det signal is modified by allocating it the value 1 (RDA_Det is 1), which means that an assisted-start refusal has been detected. The Act_Codage signal is also modified by allocating it the value 0 (Act_Codage is 0), which means that the encoding of the diagnostic information items is stopped. After the signaling step 115 , the waiting step 102 is carried out.
The method for detecting the assisted-start refusal makes it possible, based on the diagnostic signals established by the input module 3 , to signal, by the enabling of the RDA_Det signal, that a start refusal has been detected. The method also makes it possible to determine the type of refusal and the signal by the management of the RDAType signal. Moreover, the method enables, by means of the Act_Codage signal, the encoding module 6 when an assisted start is in progress.
The steps of the detection method can be implemented by an electronic circuit or in software form, or in a programmable controller, implemented in the detection module 5 .
FIG. 4 shows a schematic view of a general embodiment of a module for encoding an item of diagnostic information. Also shown in FIG. 4 are elements previously described with reference to FIGS. 1 and 2 .
The encoding module 6 comprises an encoding means 60 for encoding an item of diagnostic Signal information sent from the input module 3 and transmitted via the connection 14 . This item of Signal information may be, for example, the EtatMoteur, Vvéh or RotationMoteur information item.
The encoding means 60 makes it possible to receive a Signal signal, or an item of information, from the input module 3 for comparing this Signal information item with a threshold, marked Seuil, in order to transmit a Boolean Cond_Signal signal of satisfactory condition as a function of the comparison result. Then, with the aid of an encoding method, which will be described below with reference to FIGS. 6 a to 6 d , a monitoring SignalCode signal is generated as a function of the evolution over time of the Cond_Signal signal during the assisted start. The generation of the monitoring SignalCode signal is enabled when the Act_Codage input signal is 1 and said monitoring signal is saved, by means of the saving module 7 , when an assisted-start refusal is detected, that is to say when the RDA_Det signal is 1.
The encoding means 60 comprises an encoding block 61 , a comparison means 62 and a configurable module 63 for generating the Seuil signal. The comparison module 62 compares the Signal signal, originating from the input module 3 and transmitted via the connection 14 , with the Seuil signal originating from the module 63 and transmitted via a connection 64 . The comparison module sends the Cond_Signal result of the comparison, transmitted via a connection 65 , to the encoding block 61 .
The satisfactory condition Cond_Signal signal, the result of the comparison, is determined as follows:
Cond_Signal: a Boolean signal which is:
0 if the result of the comparison between the Signal and Seuil signals is false 1 if the result of the comparison between the Signal and Seuil signals is true.
The encoding block 61 also receives a Val_Signal signal from the detection module 5 via the connection 12 , the RDA_Det signal from the detection module 5 via the connection 52 , the Act_Codage signal from the detection module 5 via the connection 53 and the DA_Actif signal from the assisted-start management module 4 via a connection 67 . The Val_Signal signal corresponds to a Boolean signal of validity which is generated by the signal-validity test module 21 . This Val_Signal signal makes it possible to determine the validity of the Signal signal:
Val_Signal: a Boolean signal of validity of the Signal signal, which is:
0 if the Signal signal is invalid 1 if the Signal signal is valid.
After the execution of the encoding method carried out by the encoding block 61 , said block 61 sends the SignalCode monitoring signal which corresponds to the result of the encoding method and transmits it via a connection 66 to the saving module 7 .
FIG. 5 shows a schematic view of an embodiment of a module 6 for encoding the items of diagnostic information. Also shown in FIG. 5 are elements previously described with reference to FIGS. 1 to 4 .
The encoding module 6 comprises encoding means 500 to 503 for encoding the items of received diagnostic information. Each encoding means 500 to 503 comprises respectively an encoding block 504 to 507 . The encoding blocks 504 to 507 each make it possible to apply a method for encoding the items of diagnostic information. This method for encoding an item of diagnostic information will be described later with reference to FIGS. 6 a to 6 d . The encoding method is identical for each encoding block 504 to 507 .
The signals representing the items of diagnostic information have been selected from many signals which report the general state of the system. Four main signals have been selected, RotationMoteur, AccPos, BV_Pos and CoupleRoues, which represent four conditions which must be met simultaneously in order to generate an automatic command to release the parking brake 1 .
The encoding means 500 also comprises a comparison means 510 and a module 511 for generating a configurable Seuil1 threshold. The comparison means 510 compares the RotationMoteur signal, originating from the input module 3 and transmitted via a connection 512 , with the Seuil1 threshold originating from the module 511 and transmitted via a connection 513 . The comparison means 510 sends the Cond_RotationMoteur result of the comparison, transmitted via a connection 514 , to the encoding block 504 . The Cond_RotationMoteur signal of satisfactory condition, the result of the comparison, is determined as follows:
Cond_RotationMoteur: a Boolean signal which is:
0 if the rotation speed of the engine is insufficient to allow an assisted start, that is to say if the item of information on the rotation speed of the engine RotationMoteur is less than or equal to the Seuil1 threshold 1 if the rotation speed of the engine is sufficient to allow an assisted start, that is to say if the item of information on the rotation speed of the engine RotationMoteur is strictly greater than the Seuil1 threshold.
The encoding block 504 also receives the Val_RotationMoteur signal from the detection module 5 via the connection 54 , the DA_Actif signal from the assisted-start management module 4 via a connection 515 , the Act_Codage signal from the detection module 5 via a connection 516 and the RDA_Det signal from the detection module 5 via a connection 517 . The encoding block 504 sends a monitoring signal RotationMoteurCode which corresponds to the result of the encoding method and transmits it via a connection 518 to the saving module 7 .
The encoding means 501 also comprises a comparison means 520 and a module 521 for generating a configurable Seuil2 threshold. The comparison means 520 compares the AccPos signal, originating from the input module 3 and transmitted via a connection 522 , with the Seuil2 threshold originating from the module 521 and transmitted via a connection 523 . The comparison means 520 sends the Cond_AccPos result of the comparison, transmitted via a connection 524 , to the encoding block 505 . The Cond_AccPos satisfactory condition signal, the result of the comparison, is determined as follows:
Cond_AccPos: a Boolean signal which is:
0 if the position of the accelerator pedal of the vehicle is insufficient to allow an assisted start, that is to say if the item of information on the speed position of the accelerator pedal of the vehicle AccPos is less than or equal to the Seuil2 threshold 1 if the position of the accelerator pedal of the vehicle is sufficient to allow an assisted start, that is to say if the item of information on the speed position of the accelerator pedal of the vehicle AccPos is strictly above the Seuil2 threshold.
The encoding block 505 also receives the Val_AccPos signal from the detection module 5 via the connection 55 , the DA_Actif signal from the assisted-start management module 4 via a connection 525 , the Act_Codage signal from the detection module 5 via a connection 526 and the RDA_Det signal from the detection module 5 via a connection 527 . The encoding block 505 sends a monitoring AccPosCode signal which corresponds to the result of the encoding method and transmits it via a connection 528 to the saving module 7 .
The encoding means 502 also comprises a comparison means 530 and a module 531 for generating a configurable Seuil3 threshold. The comparison means 530 compares the BV_Pos signal, originating from the input module 3 and transmitted via a connection 532 , with the Seuil3 threshold originating from the module 531 and transmitted via a connection 533 . The comparison means 530 sends the Cond_BV_Pos result of the comparison, transmitted via a connection 534 , to the encoding block 506 . The satisfactory condition Cond_BV_Pos signal, the result of the comparison, is determined as follows:
Cond_BV_Pos: a Boolean signal which is:
0 if no gear ratio is engaged, that is to say if the item of information on the position of the gearbox is equal to the Seuil3 threshold (where Seuil3 is equal to 0) 1 if at least one gear ratio is engaged, that is to say if the item of information on the position of the gearbox is strictly greater than said Seuil3.
The encoding block 506 also receives the Val_BV_Pos signal from the detection module 5 via the connection 56 , the DA_Actif signal from the assisted-start management module 4 via a connection 535 , the Act_Codage signal from the detection module 5 via a connection 536 and the RDA_Det signal from the detection module 5 via a connection 537 . The encoding block 506 sends a monitoring BV_PosCode signal which corresponds to the result of the encoding method and transmits it via a connection 538 to the saving module 7 .
The encoding means 503 also comprises a comparison means 540 and a module 541 for generating a configurable Seuil4 threshold. The comparison means 540 compares the CoupleRoues signal, originating from the input module 3 and transmitted via a connection 542 , with the Seuil4 threshold originating from the module 541 and transmitted via a connection 543 . The comparison means 540 sends the Cond_CoupleRoues result of the comparison, transmitted via a connection 544 , to the encoding block 507 . The satisfactory condition Cond_CoupleRoues signal, the result of the comparison, is determined as follows:
Cond_CoupleRoues: a Boolean signal which is:
0 if the torque transmitted to the wheels is insufficient to allow an assisted start, that is to say if the item of information on the torque transmitted to the wheels CoupleRoues is less than or equal to the Seuil4 threshold 1 if the torque transmitted to the wheels is sufficient to allow an assisted start, that is to say if the item of information on the torque transmitted to the wheels CoupleRoues is strictly greater than the Seuil4 threshold.
The encoding block 507 also receives the Val_CoupleRoues signal from the detection module 5 via the connection 57 , the DA_Actif signal from the assisted-start management module 4 via a connection 545 , the Act_Codage signal from the detection module 5 via a connection 546 and the RDA_Det signal from the detection module 5 via a connection 547 . The encoding block 507 sends a monitoring CoupleRouesCode signal which corresponds to the result of the encoding method and transmits it via a connection 548 to the saving module 7 .
It will be noted that the various thresholds Seuil1 to Seuil4 can be configured and are determined as a function of the slope, the weight of the vehicle, the engine type, etc.
Similarly, the encoding module 6 may comprise other encoding means for encoding the item of diagnostic information of other signals.
FIGS. 6 a , 6 b , 6 c and 6 d represent a flow chart illustrating the main phases of a method for encoding an item of diagnostic information. This method can be applied to any item of information selected for the purpose of producing a diagnosis, such as for example to the items of information BV_Pos, RotationMoteur, AccPos or CoupleRoues.
The encoding method consists in monitoring the temporal evolution of an item of diagnostic Signal information transmitted by the input module 3 . This item of diagnostic Signal information may change value during the assisted start. These various changes correspond to distinct states of the item of diagnostic Signal information. Moreover, the method is capable of determining the distinct states of this item of diagnostic Signal information and of allocating a different value to the monitoring SignalCode signal for each distinct state.
The encoding method begins with an initial step 200 . During this step 200 , the SignalCode output signal is set to the value −1.
After this initial step 200 , a comparison step 201 is carried out in which the validity of the following condition is tested:
the encoding of the items of information is enabled (Act_Codage is 1).
If this condition is verified, a comparison step 202 is carried out, otherwise the initial step 200 is carried out again.
In the comparison step 202 , the validity of the following three conditions is tested:
the satisfactory condition signal is false (Cond_Signal is 0) the item of Signal information is valid (Val_Signal is 1) the assisted start is enabled (DA_Actif is 1).
If the three conditions are verified, a step 203 is carried out, otherwise a following comparison step 211 is carried out.
In the comparison step 211 , the validity of the following three conditions is tested:
the satisfactory condition signal is true (Cond_Signal is 1) the item of Signal information is valid (Val_Signal is 1) the assisted start is enabled (DA_Actif is 1).
If the three conditions are met, a step 212 is carried out, otherwise a following comparison step 220 is carried out.
In the comparison step 220 , the validity of the following two conditions is tested:
the item of Signal information is invalid (Val_Signal is 0) the assisted start is disabled (DA_Actif is 0).
If the two conditions are met, a step 221 is carried out, otherwise a following comparison step 223 is carried out.
In the step 221 , the code 6 is allocated to the monitoring SignalCode signal (SignalCode is 6), then a comparison step 222 is carried out in which the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 221 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the comparison step 223 , the validity of the following two conditions is tested:
the item of Signal information is valid (Val_Signal is 1) the assisted start is disabled (DA_Actif is 0).
If the two conditions are met, a step 224 is carried out, otherwise a following comparison step 226 is carried out.
In the step 224 , the code 7 is allocated to the monitoring SignalCode signal (SignalCode is 7), then a comparison step 225 is carried out in which the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 224 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the comparison step 226 , the validity of the following two conditions is tested:
the item of Signal information is invalid (Val_Signal is 0) the assisted start is enabled (DA_Actif is 1).
If the two conditions are met, a step 227 is carried out, otherwise the initial step 200 is carried out again.
In the step 227 , the code 8 is allocated to the monitoring SignalCode signal (SignalCode is 8), then a comparison step 228 is carried out in which the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 227 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 203 , the code 0 is allocated to the monitoring SignalCode signal (SignalCode is 0), then a comparison step 204 is carried out in which the value of the satisfactory condition Cond_Signal signal is tested. If the Cond_Signal signal is 1, a step 206 is carried out, otherwise a comparison step 205 is carried out.
In the comparison step 205 , the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 203 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 206 , the code 1 is allocated to the monitoring SignalCode signal (SignalCode is 1), then a comparison step 207 is carried out in which the value of the satisfactory condition Cond_Signal signal is tested. If the Cond_Signal signal is 0, a step 209 is carried out, otherwise a comparison step 208 is carried out.
In the comparison step 208 , the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 206 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 209 , the code 2 is allocated to the monitoring SignalCode signal (SignalCode is 2), then a comparison step 210 is carried out in which the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 209 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 212 , the code 3 is allocated to the monitoring SignalCode signal (SignalCode is 3), then a comparison step 213 is carried out in which the value of the satisfactory condition Cond_Signal signal is tested. If the Cond_Signal signal is 0, a step 215 is carried out, otherwise a comparison step 214 is carried out.
In the comparison step 214 , the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 212 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 215 , the code 4 is allocated to the monitoring SignalCode signal (SignalCode is 4), then a comparison step 216 is carried out in which the value of the satisfactory condition Cond_Signal signal is tested. If the Cond_Signal signal is 1, a step 218 is carried out, otherwise a comparison step 217 is carried out.
In the comparison step 217 , the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 215 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the step 218 , the code 5 is allocated to the monitoring SignalCode signal (SignalCode is 5), then a comparison step 219 is carried out in which the value of the Act_codage signal is tested. If the Act_codage signal is 1, the step 218 is carried out again, otherwise the encoding of the item of received Signal information is stopped and a step 300 is carried out to finish the encoding.
In the comparison step 300 , a test is run to ascertain whether an assisted-start refusal has been detected during the assisted start. If a refusal is detected, the value of the monitoring SignalCode signal is saved, otherwise there is a return to the initial step 200 .
Specifically, the comparison step 300 is carried out in which the value of the RDA_Det signal is tested. If the RDA_Det signal is 0, the initial step 200 is carried out again because no refusal has been detected. Otherwise, when the RDA_Det signal is 1, a saving step 301 is carried out in which the value of the monitoring SignalCode signal is recorded because a refusal has been detected, then the initial step 200 is carried out again.
The steps of the encoding method can be applied by an electronic circuit or in software form, or in a programmable controller, implemented in the encoding blocks 504 to 507 . | A method and system for diagnosing an operating status of an assisted start-up mode for a motor vehicle. The system includes a driving engine, a transmission including a mechanism determining a piece of engine rotation speed information, a piece of information on a position of an accelerator pedal of the vehicle, a piece of information on a position of a transmission, and a piece of information on torque transmitted to wheels, a detection mechanism producing a malfunction signal for the assisted start-up using the information received, a plurality of encoding mechanisms to produce a follow-up signal for each piece of calculated information received, and a memory saving the follow-up signals. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a filler-fiber composite, a process for its production, the use of such in the manufacture of paper or paperboard products and to paper produced therefrom. More particularly the invention relates to a filler-fiber composite in which the morphology and particle size of the mineral filler are established prior to the development of the bond to the fiber. Even more particularly, the present invention relates to a PCC filler-fiber composite, wherein the desired optical and physical properties of the paper produced therefrom are realized.
BACKGROUND OF THE INVENTION
[0002] Loading particulate fillers such as calcium carbonate, talc and clay on fibers for the subsequent manufacture of paper and paper products continues to be a challenge. A number of methods, having some degree of success, have been used to address this issue. To insure that fillers remain with or within the fiber web, retention aids have been used, direct precipitation onto the fibers have been used, a method to attach the filler directly to the surface of the fiber have been used, mixing the fiber and the filler have been used, precipitation within never dried pulp have been used, a method for filling the cellulosic fiber have been used, high shear mixing have been used, fiberous material and calcium carbonate have been reacted with carbon dioxide in a closed pressurized container, fillers have been trapped by mechanical bonding, cationically charged polymers have been used and pulp fiber lumen loaded with calcium carbonate have all been used to retain filler in fiber for subsequent use in paper. Most of the methods for fiber retention are both expensive and ineffective.
[0003] Therefore, what is needed is a filler fiber composite and a method for producing the same that is both effective in retaining the filler and inexpensive for the paper maker to utilize.
[0004] Therefore, an object of the present invention is to produce a filler-fiber composite. Another object of the present invention is to provide a method for producing a filler-fiber composite. While another object of the present invention is to produce a filler-fiber composite that maintains physical properties such as tensile strength, breaking length and internal bond strength. Still a further object of the present invention is to produce a filler-fiber composite that maintains optical properties such as ISO opacity and pigment scatter. While still a further object of the present invention is to provide a filler-fiber composite that is particularly useful in paper and paperboard products.
RELATED ART
[0005] U.S. Pat. No. 6,156,118 teaches mixing a calcium carbonate filler with noil fibers in a size of P50 or finer.
[0006] U.S. Pat. No. 5,096,539 teaches in-situ precipitation of an inorganic filler with never dried pulp.
[0007] U.S. Pat. No. 5,223,090 teaches a method for loading cellulosic fiber using high shear mixing of crumb pulp during carbon dioxide reaction.
[0008] U.S. Pat. No. 5,665,205 teaches a method for combining a fiber pulp slurry and an alkaline salt slurry in the contact zone of a reactor and immediately contacting the slurry with carbon dioxide and mixing so as to precipitate filler onto secondary pulp fibers.
[0009] U.S. Pat. No. 5,679,220 teaches a continuous process for in-situ deposition of fillers in papermaking fibers in a flow stream in which shear is applied to the gaseous phase to complete the conversion of calcium hydroxide to calcium carbonate immediately.
[0010] U.S. Pat. No. 5,122,230 teaches process for modifying hydrophilic fibers with a substantially water insoluble inorganic substance in-situ precipitation.
[0011] U.S. Pat. No. 5,733,461 teaches a method for recovery and use of fines present in a waste water stream produced in a paper manufacturing process.
[0012] U.S. Pat. No. 5,731,080 teaches in-situ precipitation wherein the majority of a calcium carbonate trap the microfiber by reliable and non-reliable mechanical bonding without binders or retention aids.
[0013] U.S. Pat. No. 5,928,470 teaches method of making metal oxide or metal hydroxide-modified cellulosic pulp.
[0014] U.S. Pat. No. 6,235,150 teaches a method of producing a pulp fiber lumen loaded with calcium carbonate having a particle size of 0.4 microns to 1.5 microns.
[0015] The problem of insuring that filler materials, such as calcium carbonate, ground calcium carbonate, clay and talc, remain within fibers that are ultimately to be used in paper has been subjected to a number of proofs. However, none of the prior related art discloses a filler fiber composite where the morphology of the filler is predetermined prior to introducing fibers, a method for its production nor its use in paper or paper products.
SUMMARY OF THE INVENTION
[0016] The present invention relates to a filler-fiber composite including feeding slake containing seed to a first stage reactor, reacting the slake containing seed in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry, reacting the first partially converted calcium hydroxide calcium carbonate slurry in a second stage reactor in the presence of carbon dioxide to produce a second partially converted calcium hydroxide calcium carbonate slurry and reacting the second partially converted calcium hydroxide calcium carbonate slurry in a third stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite.
[0017] In another aspect, the present invention relates to a filler-fiber composite including feeding slake containing seed to a first stage reactor, reacting the slake containing seed in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry and reacting the first partially converted calcium carbonate slurry in a second stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite.
[0018] In a further aspect, the present invention relates to a filler-fiber composite including feeding slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry, reacting the first partially converted calcium hydroxide calcium carbonate slurry in a second stage reactor in the presence of carbon dioxide to produce a second partially converted calcium hydroxide calcium carbonate slurry, and reacting the second partially converted calcium hydroxide calcium carbonate slurry in a third stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite.
[0019] In yet a further aspect, the present invention relates to a filler-fiber composite Including feeding slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry, taking a first portion of the partially converted calcium hydroxide calcium carbonate slurry adding fibers and reacting such in a second stage reactor in the presence of carbon dioxide to produce a calcium carbonate\fiber composite to serve as a heel and taking a second portion of the partially converted calcium hydroxide calcium carbonate slurry adding fibers and surfactant and reacting in the presence of CO 2 to produce a second partially converted Ca(OH) 2 /CaCO 3 /fiber material and reacting the second partially converted Ca(OH) 2 /CaCO 3 /fiber material in the presence of CO 2 in a third stage reactor to produce a filler-fiber composite.
[0020] In still a further aspect, the present invention relates to a filler-fiber composite including feeding slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry, taking a first portion of the partially converted calcium hydroxide calcium carbonate slurry adding fibers and reacting such in a second stage reactor in the presence of carbon dioxide to produce a calcium carbonate/fiber composite to serve as a heel and taking a second portion of the partially converted calcium hydroxide calcium carbonate slurry adding fibers and polyacrylamide and reacting in the presence of CO 2 to produce a second partially converted Ca(OH) 2 /CaCO 3 /fiber material and reacting the second partially converted Ca(OH) 2 /CaCO 3 /fiber material in the presence of CO 2 in a third stage reactor to produce a filler-fiber composite.
[0021] In a final aspect, the present invention relates to a filler-fiber composite including feeding slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide to produce a CaCO 3 heel and adding slake containing sodium carbonate to the heel material of the first stage reactor in the presence of CO 2 to produce a partially converted calcium hydroxide calcium carbonate slurry and reacting the partially converted calcium hydroxide calcium carbonate slurry in a second stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite.
[0022] Fiber as used in the present invention is defined as fiber produced by refining (any pulp refiner known in the pulp processing industry) cellulose and/or mechanical pulp fiber. The fibers are typically 0.1 to 2 microns in thickness and 10 to 400 microns in length and are additionally prepared according to U.S. Pat. No. 6,251,222, which is by this reference incorporated herein.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Precipitation of PCC with Varying Morphologies
[0024] Continuous Flow Stir Tank Reactor (CFSTR)
[0025] Scalenohedral Morphology
[0026] The first step in this process involves making a high reactive Ca(OH) 2 milk-of-lime slake and screening it at −325 mesh. This slake is then added to an agitated reactor, brought to a desired reaction temperature, 0.1 percent citric acid is added to the slake to inhibit aragonite formation, and reacted with CO 2 gas. The reaction proceeds 10 percent to 40 percent of the way through at which point the reaction is stopped. This produces a partially converted Ca(OH) 2 /CaCO 3 slurry (approximately 20 percent solids by weight) which is then fed into a reaction vessel at a rate that matches CO 2 gassing to maintain a given conductivity (ionic saturation) to produce a scalenohedral crystal. This reaction proceeds until stabilization of the process is achieved. The product made once stabilization is achieved (approximately 95 percent converted) is then mixed with diluted fibers (approximately 1.5 percent concentration) and water. This mixture is then reacted with CO 2 gas to endpoint pH 7.0. The product manufactured using this method can contain from about 0.2 percent to about 99.8 percent scalenohedral PCC with respect to fibers at 3 percent to 5 percent total solids.
[0027] The product has a specific surface area from about 5 meters squared per gram to about 11 meters squared per gram; product solids from about 3 percent to about 5 percent and a PCC content from about 0.2 percent to about 99.8 percent, and is predominantly scalenohedral in morphology.
[0028] Aragonitic Morphology
[0029] The first step in this process involves making a high reactive Ca (OH) 2 milk-of-lime slake and screened at −325 mesh. The concentration of this slake is approximately 15 percent by weight. This slake is then added to an agitated reactor, brought to a desired reaction temperature, from about 0.05 percent to about 0.04 percent additive is added to direct morphology and size, and reacted with CO 2 gas. The reaction proceeds 10 percent to 40 percent of the way through at which point the reaction is stopped. This produces a partially converted Ca (OH) 2 /CaCO 3 slurry which is then fed into a reaction vessel at a rate that matches CO 2 gassing to maintain a given conductivity (ionic saturation) to produce an acicular, aragonitic crystal. The reaction continues until process stabilization is achieved. The product made once stabilization is achieved, (approximately 95 percent calcium carbonate) is mixed with diluted fibers (approximately 1.5 percent concentration) and water. The calcium carbonate and fibers are then reacted with CO 2 gas to an endpoint of pH 7.0. The product manufactured using this method contains from about 0.2 percent to about 99.8 percent aragonitic PCC with respect to the fibers at about 3 percent to about 5 percent total solids.
[0030] The product has a specific surface area of about 5 meters squared per gram to about 8 meters squared per gram; product solids from about 3 percent to about 5 percent by weight and a PCC content from about 0.2 percent to about 99.8 percent with respect to fibers and has a predominantly aragonitic morphology.
[0031] Rhombohedral Morphology
[0032] The first step in this process involves making a high reactive Ca (OH) 2 milk-of-lime slake which is screened at −325 mesh and has a concentration of approximately 20 percent by weight. 0.1 percent citric acid is added to inhibit aragonite formation. A portion of this slake is added to an agitated reactor, brought to a desired reaction temperature and carbonated with CO 2 gas. The reaction proceeds to conductivity minimum producing a “heel”. A “heel” is defined as a fully converted calcium carbonate crystal with average particle size typically in the range of about 1 micron to about 2.5 micron with any crystal morphology. Sodium carbonate is added to the remainder of the slake not used in the manufacture of the “heel” material. This slake and CO 2 is added to the “heel” material at a CO 2 gassing rate to maintain a given conductivity (ionic saturation) to produce a rhombohedral crystal. The reaction is continued until process stabilization is achieved. Once stabilization is achieved, this product (approximately 90 percent to 95 percent converted) is mixed with diluted fibers (approximately 1.5 percent concentration) and water. Additional CO 2 is added to an endpoint of pH 7.0. The product manufactured using this method contains from about 0.2 percent to about 99.8 percent rhombohedral PCC with respect to fibers and is about 3 percent to about 5 percent total solids.
[0033] The product has a specific surface area from about 5 meters squared per gram to about 8 meters squared per gram; product solids from about 3 percent to about 5 percent; and PCC content from about 0.2 percent to about 99.8 percent and has a predominantly rhombohedral morphology:
EXAMPLES
[0034] The following examples are intended to exemplify the invention and are not intended to limit the scope of the invention.
Example 1
[0035] Scalenohedral PCC
[0036] Reacted 15 liters of water with 3 kilogram CaO at 50 degrees Celsius producing a 20 percent by weight Ca(OH) 2 slake. The Ca(OH) 2 slake was then screened at −325 mesh producing a screened slake that was transferred to a first 30-liter double jacketed stainless steel reaction vessel with an agitation of 615 revolutions per minute (rpm). 0.1 percent citric acid, by weight of total theoretical CaCO 3 to be produced, was added to the screened slake in a 30-liter reaction vessel and the temperature of the contents brought to 40 degrees Celsius. Began addition of 20 percent CO 2 gas in air (14.83 standard liter minute CO 2 /59.30 standard liter minute air) to the 30-liter reaction vessel to produce a 2:1 Ca (OH) 2 /CaCO 3 slurry. At this point, CO 2 gassing was stopped and the slurry was transferred to an agitated 20-liter storage vessel.
[0037] 2 liters of the 2:1 Ca(OH) 2 /CaCO 3 slurry was transferred to a first 4-liter agitated (1250 rpm) stainless steel, double jacketed reaction vessel. The temperature was brought to 51 degrees Celsius and 20 percent CO 2 gas in air (1.41 standard liter minute CO 2 /5.64 standard liter minute air) was added to the first 4-liter reaction vessel until a pH of 7.0 was achieved producing a CaCO 3 slurry. Once a pH 7.0 was achieved began addition of the 2:1 Ca(OH) 2 /CaCO 3 slurry of the 20-liter storage vessel to the first 4-liter reaction vessel while continuing to add 20 percent CO 2 gas in air (1.41 standard liter minute CO 2 /5.64 standard liter minute air) to the first 4-liter reaction vessel to maintain a conductivity of approximately 90 percent ionic saturation. The addition of Ca(OH) 2 /CaCO 3 slurry and CO 2 to the first 4-liter reaction vessel was continued for approximately 12 hours until product physical properties remained essentially unchanged, producing a CaCO 3 slurry that was approximately 98 percent converted. Transferred 0.18 liters of the 98 percent CaCO 3 slurry to a second 4-liter agitated (1250 rpm), stainless steel, double jacketed reaction vessel, added 0.66 liters of 3.8 percent by dry weight cellulosic fibers and diluted to 1.5 percent consistency. This mixture of CaCO 3 slurry and fiber was reacted with 20 percent CO 2 in air (1.41 standard liter minute CO 2 /5.64 standard liter minute air) to produce a CaCO 3 filler-fiber composite. The calcium carbonate filler had a predominantly scalenohedral morphology.
Example 2
[0038] Aragonitic PCC
[0039] Reacted 10.5 liters of water with 2.1 kilograms CaO at 50 degrees Celsius producing a 15 percent by weight Ca(OH) 2 slake. The Ca(OH) 2 slake was then screened at −325 mesh producing a screened slake that was transferred to a 30-liter double jacketed stainless steel reaction vessel with an agitation of 615rpm. Added 0.1 percent by weight of a high surface area (HSSA) aragonitic seed (surface area ˜40 meters squared per gram, approximately 25 percent solids) to the 30-liter reaction vessel and brought the temperature of the contents to 51 degrees Celsius. A “seed” is defined as a fully converted aragonitic crystal that has been endpointed and milled to a high specific surface area (i.e. greater than 30 meters squared per gram and typically a particle size of 0.1 to 0.4 microns). Began addition of 10 percent CO 2 gas in air (5.24 standard liter minute CO 2 /47.12 standard liter minute air) to the 30-liter stainless steel, double jacketed reaction vessel for a 15-minute period after which the CO 2 concentration was increased to 20 percent in air (10.47 standard liter minute CO 2 /41.89 standard liter minute air) for an additional 15 minutes producing a 2.3:1 Ca (OH) 2 /CaCO 3 slurry. At which time CO 2 gassing was stopped. The 2.3:1 Ca(OH) 2 /CaCO 3 slurry was transferred to an agitated 20-liter storage vessel. Transferred 2 liters of the 2.3:1 Ca(OH) 2 /CaCO 3 slurry to a first 4-liter agitated, double jacketed stainless steel reaction vessel with agitation set at 1250rpm and the temperature was brought to 52 degrees Celsius. Began addition of 20 percent CO 2 gas in air (1.00 standard liter minute CO 2 /3.99 standard liter minute air) to the first 4-liter reaction vessel and the reaction was continued until a pH of 7.0 was achieved producing a 100 percent CaCO 3 slurry. The temperature of the 100 percent CaCO 3 slurry of the first 4-liter reaction vessel was brought to 63 degrees Celsius. Began addition of the 2.3:1 Ca(OH) 2 /CaCO 3 slurry of the 20-liter storage vessel to the first 4-liter reaction vessel while continuing to add 20 percent CO 2 in air (1.00 standard liter minute CO 2 /3.99 standard liter minute air) to the first 4-liter reaction vessel maintaining a conductivity of approximately 90 percent ionic saturation. Continued the reaction for approximately 9 hours until the physical properties of the resultant product remained essentially unchanged, producing a 98 percent by wt. CaCO 3 slurry.
[0040] Transferred 0.35 liters of the 98 percent CaCO 3 slurry to a second 4-liter agitated (1250 rpm), stainless steel, double jacketed reaction vessel, added 0.66 liters of 3.8 percent by wt. cellulosic fiber and 1.0 liters water to the second 4-liter reactor producing a 1.5 percent by wt. CaCO 3 /fiber mixture. Added an additional 20 percent CO 2 in air (1.00 standard liter minute CO 2 /3.99 standard liter minute air) to the second 4-liter reaction vessel until a pH of 7.0 was reached at which time the reaction was completed producing a CaCO 3 /fiber composite. The composite consisted of approximately 75 percent aragonitic PCC to fiber.
Example 3
[0041] Rhombohedral PCC
[0042] Reacted 15 liters of water with 3 kilograms CaO at 50 degrees Celsius producing a 20 percent by weight Ca(OH) 2 slake. The Ca(OH) 2 slake was screened at −325 mesh producing a screened slake that was transferred to an agitated 20-liter storage vessel. Transferred 2-liters of the screened slake from the 20-liter storage vessel to a first 4-liter agitated, stainless steel, double jacketed reaction vessel and began agitation at 1250 rpm. Added 0.03 percent citric acid by weight of theoretical CaCO 3 to the first 4-liter reaction vessel and raised the temperature of the contents to 50 degrees Celsius. Added 20 percent CO 2 gas in air (1.44 standard liter minute CO 2 /5.77 standard liter minute air) to the first 4-liter reaction vessel until a pH of 7.0 was achieved producing a 100 percent CaCO 3 slurry. To the screened slake in the 20-liter storage vessel, added a solution of 1.3 percent by weight of Na 2 CO 3 , based on theoretical yield of CaCO 3 , producing a Ca(OH) 2 /Na 2 CO 3 slake. Increased the temperature of the contents of the first 4-liter reaction vessel to approximately 68 degrees Celsius and began addition of the Ca(OH) 2 /Na 2 CO 3 slake of the 20-liter storage vessel to the first 4-liter reaction vessel while continuing to add 20 percent CO 2 in air (1.44 standard liter minute CO 2 /5.77 standard liter minute air) to the first 4-liter reaction vessel maintaining a conductivity of approximately 50 percent ionic saturation. Addition of the Ca(OH) 2 /Na 2 CO 3 slake and CO 2 was continued for approximately 12 hours until physical properties of the resultant product remained essentially unchanged producing an approximate 98 percent by wt. CaCO 3 slurry.
[0043] Transferred 0.22 liters of the 98 percent CaCO 3 slurry to a second 4-liter agitated (1250 rpm) dual jacketed, stainless steel reaction vessel and added 0.66 liters of 3.8 percent by weight cellulosic fiber and 1.0 liters water to the second 4-liter reactor producing a 1.5 percent by weight CaCO 3 /fiber mixture. Added an additional 20 percent CO 2 in air (1.44 standard liter minute CO 2 /5.77 standard liter minute air) to the second 4-liter reaction vessel until a pH of 7.0 was reached at which time the reaction was completed producing an approximate 3.4 percent by wt CaCO 3 /fiber composite. The calcium carbonate had a predominantly rhombohedral morphology.
Example 4
[0044] Scalenohedral—CFSTR
[0045] Reacted 15 liters of water with 3 kilograms CaO at 48 degrees Celsius to produce a Ca(OH) 2 slake, added an additional 6 liters of water producing a 20 percent by weight Ca(OH) 2 slake. The 20 percent Ca(OH) 2 slake was screened at −325 mesh and transferred to a 30-liter double jacketed, stainless steel reaction vessel with an agitation of 615rpm. Added 0.015 percent citric acid, by weight of total theoretical CaCO 3 to be produced, to the 30-liter reaction vessel and the temperature of the contents brought to 36 degrees Celsius. Began addition of 20 percent CO 2 gas in air (13.72 standard liter minute CO 2 /54.89 standard liter minute air) to the 30-liter reaction vessel to produce a 5:1 Ca(OH) 2 /CaCO 3 slurry. CO 2 gassing was stopped and the Ca(OH) 2 /CaCO 3 slurry was transferred to an agitated 20-liter storage vessel.
[0046] In a 4-liter agitated storage vessel, combined 0.25 liters of the Ca(OH) 2 /CaCO 3 slurry with 0.66 liters of 3.8 percent by weight fibers and with 1.09 liters of water making a Ca(OH) 2 /CaCO 3 /fiber material. Transferred 2 liters of the Ca(OH) 2 /CaCO 3 /fiber material to a 4-liter agitated (1250 revolutions per minute) reaction vessel and the temperature brought to 55 degrees Celsius and carbonated with 20 percent CO 2 in air (1.30 standard liter minute CO 2 /5.23 standard liter minute air) to a pH of 7.0 producing a CaCO 3 /fiber composite. Prepared 16-liters of 1.5 percent by weight fibers and a separate 10-liter vessel of water. To the 4-liter reaction vessel began addition of the Ca(OH) 2 /CaCO 3 slurry of the 20-liter agitated storage vessel, along with the 1.5 percent consistency fiber mixture at 172.05 ml per minute, along with 31.21 ml per minute of additional water while maintaining the flow of CO 2 gas (1.30 standard liter minute CO 2 /5.23 standard liter minute air) at a rate to maintain conductivity of approximately 90 percent ionic saturation, while maintaining mass balance of approximately 4 percent to 5 percent total solids.
[0047] This reaction was continued until product physical properties remained essentially unchanged. Addition of material from the storage vessel was stopped while CO 2 addition was continued and the material in the 4-liter agitated reaction vessel was brought to a pH of 7.0 at which time CO 2 addition was stopped producing a 2.2:1 CaCO 3 /fiber composite with the CaCO 3 having a well defined scalenohedral morphology.
Example 5
[0048] Scalenohedral CFSTR/Surfactant
[0049] Reacted 15 liters of water with 3 kilograms CaO at 48 degrees Celsius to produce a Ca(OH) 2 slake, added an additional 6 liters of water producing a 20 percent by weight Ca(OH) 2 slake. The 20 percent Ca(OH) 2 slake was screened at −325 mesh and transferred to a 30-liter reaction vessel (615 revolutions per minute). Added 0.015 percent citric acid, by weight of total theoretical CaCO3 to be produced, to the 30-liter reaction vessel and the temperature of the contents brought to 35 degrees Celsius. Began addition of 20 percent CO 2 gas in air (14.08 standard liter minute CO 2 /56.30 standard liter minute air) to the 30-liter reaction vessel producing a 5:1 Ca(OH) 2 /CaCO 3 slurry. At this point, CO 2 gassing was stopped and the Ca(OH) 2 /CaCO 3 slurry was transferred to a 20-liter agitated storage vessel.
[0050] In a 4-liter agitated storage vessel, combined 0.25 liters of the Ca(OH) 2 /CaCO 3 slurry with 0.66 liters of 3.8 percent by weight fibers and with 1.09 liters of water making 2 liters of Ca(OH) 2 /CaCO 3 /fiber material.
[0051] Transferred 2 liters of the Ca(OH) 2 /CaCO 3 /fiber material to a 4-liter stainless steel, double jacketed, agitated (1250 revolutions per minute) reaction vessel and the temperature was brought to 58 degrees Celsius. Reacted the Ca(OH) 2 /CaCO 3 /fiber material with 20 percent CO 2 in air (1.30 standard liter minute CO 2 /5.23 standard liter minute air) to a pH of 7.0.
[0052] At this point, prepared 16-liters of 1.5 percent by weight fibers (6.32 liters of fibers at 3.8 percent consistency and 9.68 liters of water) and a separate 10-liter vessel of water. Added 0.04 percent surfactant based on the volume of fibers at 1.5 percent consistency. The surfactant is Tergitol™ MIN-FOAM 2× which is available commercially from Union Carbide, 39 Old Ridgebury Road, Danbury, Conn. 06817.
[0053] Once a pH of 7.0 was achieved in the 4-liter reaction vessel, began addition of the remaining 5:1 Ca(OH) 2 /CaCO 3 slurry from the 20-liter agitated storage vessel, with a flow of the 1.5 percent fiber mixture at 176.48 ml per minute and with 32.00 ml per minute water from the 10-liter vessel to the 4-liter reaction vessel while maintaining the flow of CO 2 gas (1.30 standard liter minute CO 2 /5.23 standard liter minute air) at a rate to maintain conductivity of approximately 90 percent ionic saturation, while maintaining mass balance of approximately 4 percent to 5 percent total solids. Continued addition of the material from the agitated storage vessel to the reaction vessel until product physical properties remained essentially unchanged. At which point, addition of material from the storage vessel was stopped while CO 2 addition was continued to a pH of 7.0 at which time CO 2 addition was stopped. This produced a 2.33:1 CaCO 3 /fiber composite with the calcium carbonate having a well defined scalenohedral morphology.
Example 6
[0054] Scalenohedral CFSTR/Polyacrylamide
[0055] Reacted 15 liters of water with 3 kilograms CaO at 48 degrees Celsius producing a Ca(OH) 2 slake, added an additional 6 liters of water producing a 20 percent by weight Ca(OH) 2 slake. The 20 percent Ca(OH) 2 slake was then screened at −325 mesh producing a screened slake that was transferred to a 30-liter agitated (615 rpm) reaction vessel. Added 0.1 percent citric acid, by weight of total theoretical CaCO 3 to be produced, to the 30-liter reaction vessel and the temperature of the contents brought to 50 degrees Celsius. Began addition of 20 percent CO 2 gas in air (15.01 standard liter minute CO 2 /60.06 standard liter minute air) to the 30-liter reaction vessel producing a 5:1 Ca(OH) 2 /CaCO 3 slurry. CO 2 gassing was stopped and the slurry was transferred to a 20-liter agitated storage vessel. To a 4-liter agitated vessel added 0.31 liters of the Ca(OH) 2 /CaCO 3 slurry, 0.60 liters of fibers at 3.8 percent consistency and 1.09 liters of water to produce a Ca(OH) 2 /CaCO 3 /fiber material. 2 liters of the Ca(OH) 2 /CaCO 3 /fiber material was transferred to a 4-liter agitated (1250 revolutions per minute) reaction vessel and the temperature was brought to 51 degrees Celsius. Began addition of 20 percent CO 2 in air (1.34 standard liter minute CO 2 /5.34 standard liter minute air) until a pH of 7.0 was reached producing a CaCO 3 /fiber composite.
[0056] At this point, prepared 16-liters of 1.5 percent by weight fibers (6.32 liters of fibers at 3.8 percent consistency and 9.68 liters of water) and a separate 10-liter vessel of water. Added 0.05 percent cationic polyacrylamide (Percol 292) based on the volume of fibers at 1.5 per cent consistency. Percol 292 is commercially available from Allied Colloids, 2301 Wilroy Road, Suffolk, Va. 23434.
[0057] Once a pH of 7.0 was achieved in the 4-liter reaction vessel, began addition of the remaining 5:1 Ca(OH) 2 /CaCO 3 slurry from the 20-liter agitated storage vessel, with a flow of the 1.5 percent fiber mixture at 90 ml per minute, along with 48.5 ml per minute of additional water to the 4-liter agitated, double jacketed reaction vessel while maintaining the flow of CO 2 gas (1.30 standard liter minute CO 2 /5.23 standard liter minute air) at a rate to maintain conductivity level of approximately 90 percent ionic saturation, and maintain mass balance of the reaction to maintain product concentration at approximately 4 percent to 5 percent solids. Continued addition of the material from the agitated storage vessel to the reaction vessel until product physical properties remained essentially unchanged. Addition of material from the 20-liter storage vessel was stopped while CO 2 addition was continued until a pH of 7.0 was reached at which time CO 2 addition was stopped producing a 3.34:1 CaCO 3 /fiber composite with the PCC having a well defined scalenohedral morphology.
[0058] The control fiber of the present invention was refined at the Empire State Paper Research Institute (ESPRI) using an Escher-Wyss (conical) refiner to an 80° SR (freeness). Measured by a fiber quality analyzer (using arithmatic means) the control fiber measured 200-400 microns
[0059] How Control Filler-Fiber was Made
[0060] Produce a 15% solids slake and mix with fibers (˜1.5% consistency) React in the presence of CO 2 to endpoint of pH of 7.0 producing a filler-fiber composite with a surface area of 6-11 m2/g (˜60 to 80% PCC but can have more or less in composite)
TABLE 1 Breaking Length Physical Properties in Meters Filler Loading Scalenohedral Aragonitic Rhombohedral Control Levels Filler-fiber Filler-fiber Filler-fiber Filler-fiber 20 4,021 4,599 4,312 4,245 25 3,799 4,358 3,813 3,715 30 3,280 3,674 3,871 2,998
[0061] [0061] TABLE 2 Tensile Strength Physical Properties in kN/m Filler Loading Scalenohedral Aragonitic Rhombohedral Control Levels Filler-fiber Filler-fiber Filler-fiber Filler-fiber 20 3.062 3.555 3.397 3.382 25 3.124 3.324 2.999 3.021 30 2.658 2.785 3.005 2.448
[0062] [0062] TABLE 3 Internal Bond Strength Physical Properties in ft-lb Filler Loading Scalenohedral Aragonitic Rhombohedral Control Levels Filler-fiber Filler-fiber Filler-fiber Filler-fiber 20 237.70 264.07 283.13 255.67 25 263.20 285.95 251.65 256.95 30 242.63 248.60 273.65 249.53
[0063] The morphology controlled filler-fiber composite showed equivalent or greater physical properties (i.e. tensil strength, breaking length, and internal bond strength) as compared with the control filler-fiber.
TABLE 4 ISO Opacity Optical Properties Filler Loading Scalenohedral Aragonitic Rhombohedral Control Levels Filler-fiber Filler-fiber Filler-fiber Filler-fiber 20 89.20 88.20 87.38 88.18 25 89.93 89.15 88.78 89.55 30 90.95 90.40 89.68 90.83
[0064] [0064] TABLE 5 Pigment Scatter Optical Properties Filler Loading Scalenohedral Aragonitic Rhombohedral Control Levels Filler-fiber Filler-fiber Filler-fiber Filler-fiber 20 60.15 55.47 55.08 58.55 25 64.90 62.40 61.10 65.40 30 70.55 69.55 65.80 73.13
[0065] The morphology controlled filler-fiber composite showed equivalent optical properties (i.e. ISO Opacity and Pigment Scatter) as compared with the control filler-fiber. | The present invention relates to a filler-fiber composite, a process for its production, the use of such in the manufacture of paper or paperboard products and to paper produced therefrom. More particularly the invention relates to a filler-fiber composite in which the morphology and particle size of the mineral filler are established prior to the development of the bond to the fiber. Even more particularly, the present invention relates to a PCC filler-fiber composite, wherein the desired optical and physical properties of the paper produced therefrom are realized. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 62/114,467, filed Feb. 10, 2015, the content of which is incorporated herein in its entirety.
FIELD OF THE DISCLOSURE
[0002] The disclosure broadly relates to biomass gasification, and more particularly, to a method and system for managing solids flow in a gasifier, specifically fixed bed gasifiers such as downdraft, updraft or crossdraft gasifiers, by automatic equipment.
BACKGROUND OF THE DISCLOSURE
[0003] Gasification can convert carbon-containing materials to useful chemical products. These chemical products typically involve synthesis gas (syngas), which can be combusted to produce electricity, or chemically reacted to produce oxygenates or hydrocarbons in catalytic systems. The most common form of gasification in large scale industry is coal gasification, which is practiced on a worldwide basis, most notably by electricity producing power plants. Coal is delivered via gravity methods or via a slurry, and solids flow is not an issue at large scales. On the other hand, gasification using biomass is desirable from the point of view of decreasing greenhouse emissions, as biomass use is essentially a carbon neutral process if all the biomass is used, and can be a carbon negative process if some carbon is sequestered. Biomass use also reduces a country's dependence on fossil fuels. Due to its portability and widespread availability, biomass is used extensively in small scale gasification systems. The most common method for managing the flow of biomass through gasification systems utilizes gravity drop equipment. Major challenges with biomass flow in gasifiers include removing bridging within the gasifier, along with the need to manually shake and jiggle the biomass within the gasifier to remove jams. The clearing often necessitates stopping the gasifier, incurring a double cost of lost production and labor costs for the personnel tasked with the clearing. Clinker formation is also a problem as a result of non-uniform solids flow. In one instance, a biomass gasifier manual encourages the user to manually shake the grate vigorously with a grate shaking rod to clear them.
[0004] Prior art methods for managing solids flow in gasifier include a rotatable grate feature in U.S. Pat. No. 5,192,514 issued to Sasol, Inc. applicable to a fixed bed coal gasifier. In this gasifier configuration, coal flow is controlled via a coal lock. A rotatable grate mechanism at the bottom of the gasifier is rotatable about the vertical axis of the ash discharge outlet, and includes at least one upwardly projecting finger or disturbing formation, to disturb the ash bed formed in use above and around the rotatable grate, when the grate is rotated.
[0005] U.S. Pat. No. 5,230,716 issued to US Department of Energy discloses a rotating conical grate assembly which crushes agglomerates of clinkers at the bottom of a fixed bed gasifier by pinching them between stationary bars and angled bars on the surface of the rotating conical assembly. U.S. Pat. No. 4,764,184 teaches a rotating grate with scraping blades. U.S. Pat. No. 4,652,342 teaches a motor driven anti-bridging mechanical agitator having a crankshaft. The agitator is comprised of pushrods having scoop arms, the pushrods are driven in a reciprocating manner upwards and downwards via the crankshaft. U.S. Pat. No. 4,134,738 discloses a poking system comprising a retractable pokerod assembly used to agitate a coal bed and having means for temperature sensing clinker formation, and position sensing relative to the housing which are used to determine the frequency and extent of the actuation of the pokerod assembly. U.S. Pat. No. 4,853,992 discloses a biomass gasifier which uses a rotatable grate in conjunction with stationary bars above the grate to shear large charcoal particles so that they may be channeled through the grate.
[0006] Bridging can be a more significant issue in biomass gasifiers than in those operating with coal. Biomass undergoes significant changes in particle size and density as it traverses a gasifier, transforming to materials possessing different physical properties and different flow characteristics in the distinct drying, pyrolysis, combustion, and gasification zones. Excessive tar buildup can lead to a coating on the biomass which acts as an effective bridge between biomass particles. When this coating precipitously reaches the combustion zone, a rapid highly exothermic event can occur which destroys the zone architecture. In gasifiers that are run in conjunction with an engine, bridging can have deleterious effects on engine operation if synthesis gas is not supplied at a constant rate.
SUMMARY OF THE DISCLOSURE
[0007] Embodiments of the present disclosure are directed toward methods for preventing biomass and charcoal bridging by automating solid flow of feed material and gasification products in a fixed bed gasifier. These methods are applicable to a wide range of biomass materials and wide range of moisture levels. Constant feed rate through the gasifier is desired without logjams or congestion points. Processes are provided for clearing logjams and congestion as input biomass is converted to char or ash in vertical column gasifiers. Some methods use aliquot metering of biomass regulated by feedback from material presence sensors that monitor the extent of combustion of biomass in the gasifier. Other methods use processes to disturb solids in a radial direction without significantly disturbing the solids in the vertical direction. These methods destroy bridging without mixing combustible material with hot char. Other methods rely on shocks to shake material to assure continued movement. In some embodiments, this shock method is linked to a grate rotation to dislodge bridge particles. Still other methods use size selectivity of material as the material is reduced in size through the various stages of the gasifier, resulting in a uniform or semi-uniform product flow. Additional agitation methods also include methods for vibrationally exciting the gasifier walls and the material within.
[0008] A specific implementation of these various methods is disclosed. Aliquot distribution is implemented via intake augers that receive feedback from various material presence sensors and outtake augers that remove material once it is fully processed. The radial mixing without vertical displacement method is implemented via a shaft that is attached an auger having a large void volume and which is inserted into the reduction regime to radially mix the material in this region. Size selectivity is implemented via an adjustable grate assembly that varies its opening depending on particle size and interactively responds to solids flow through the gasifier. This is useful particularly for passing through certain types of particles, such as biochar particles. The implementation of shock-induced displacement method relies on a rotatable grate assembly that is actuated by hammer-like impacts that impinge on the grate assembly. Vibration excitation of gasifier walls is achieved via a vibrating motor attached to the gasifier walls. These embodiments are anti-jamming methods which use inputs from sensors within the gasifier. In some embodiments, the gasifier is selected from downdraft, updraft or co-current gasifiers.
[0009] The full nature of the advantages of the disclosure will become more evident from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Certain embodiments of the present disclosure will hereinafter be described in detail, by way of example only, with reference to the accompanying drawings, in which:
[0011] FIG. 1 is a diagram illustrating the various methods for preventing biomass and charcoal bridging, as set forth herein.
[0012] FIG. 2 is a diagram illustrating a system configured to implement the various methods for preventing biomass and charcoal bridging, as set forth herein.
[0013] FIG. 3 is a cross-sectional view illustrating a physical arrangement of gasifier elements in FIG. 2 .
[0014] FIG. 4 is a perspective view showing an adjustable intake auger and valve component which directs biomass in flow to the gasifier, and is a component of the metered deposition method of the disclosure.
[0015] FIGS. 5 is a top view illustrating the material presence sensor assembly used in the metering deposition method.
[0016] FIGS. 6A and FIG. 6B are cross-sectional views showing implementation of a mixing device which performs radial displacement with little vertical displacement, the mixing device comprising a retractable shaft welded to a thin auger. FIG. 6A shows the mixing device in a resting position, while FIG. 6B shows the device in a fully extended position. FIG. 6C shows the mixing action of typical auger prior art, and FIG. 6D shows mixing action enable by the present invention.
[0017] FIG. 7 is a perspective view depicting a grate assembly which is an implementation of a particle size selectivity method and a shock-induced displacement method of material within a gasifier.
[0018] FIGS. 8A and 8B are perspective views showing, respectively, completely open and completely closed grate positions achievable by servo control in the grate assembly.
[0019] FIG. 9 is a perspective view depicting a device that implements shock-induced displacement in a gasifier.
[0020] FIGS. 10A and 10B are plan views showing the different positions of a tensioner belt in a shock-induced displacement device. FIGS. 10C and FIG. 10D are corresponding top views, indicating rotation of grate by angle φ about a center axis.
[0021] FIGS. 11A and 11B are cross-sectional views illustrating the exit auger along with gate valves that control air inflow to the gasifier and prevent accidental oxidation of char.
[0022] The figures are not intended to be exhaustive or to limit the disclosure to the precise form disclosed. It should be understood that the disclosure can be practiced with modification and alteration, and that the disclosure be limited only by the claims and the equivalents thereof.
DETAILED DESCRIPTION
[0023] In the following paragraphs, embodiments of the present disclosure will be described in detail by way of example with reference to the attached drawings. Throughout this description, the preferred embodiment and examples shown should be considered as exemplars, rather than as limitations on the present disclosure. As used herein, the “present disclosure” refers to any one of the embodiments of the disclosure described herein, and any equivalents. Furthermore, reference to various feature(s) of the “present disclosure” throughout this document does not mean that all claimed embodiments or methods must include the referenced feature(s).
[0024] Embodiments of the disclosure utilize various processes and agitation methods for facilitating the flow of solids through a gasifier. In its most basic form the present invention provides for a gasifier connected to an input reservoir, grate mechanism within gasification chamber connected to an exit reservoir, material presence sensors which detect the amount and state of biomass within the gasifier, and anti-jamming mechanisms to automatically clear jams using inputs from the material presence sensors. FIG. 1 provides a list of solid flow processes and agitation methods (i.e. anti-jamming mechanisms) incorporated in the present disclosure which, separately or in combination, constitute a novel method for processing solids through a gasifier. This disclosure is applicable to any vertical gasifier relying on gravity for its operation, including counter-current, current, or co-current fixed bed gasifiers, also termed downdraft, updraft and entrained flow gasifiers. The agitation and transport methods provided in FIG. 1 transfer solids through a gasifier as material is transformed from raw form to ultimately, a carbonaceous product, ash and product gas, also referred as synthesis gas.
[0025] The raw form input is a biomass input, a term for the biodegradable fraction of agricultural products, residual or not, forestry products, industrial or municipal solid waste. Biomass generally refers to material originating from plant matter, in particular material containing cellulose, hemicellulose, lignins, lignocellulosic polymers, and extractives as composition. Forest products refers may refer to forest residue, wood pellets, wood shavings, bark, peat, waste wood, energy crops, virgin wood, recycled wood, sludge, sawdust, wood chips, as well as as black liquor and other products derived from pulp and paper operations. Biomass may also refer to herbaceous material such as miscanthus, rice husk, straw, and and sorghum as well as waste edible materials such as seeds and grains. Biomass may also refer to animal derived products such as manure. The term may also be used for a mixture of one or more of the above.
[0026] As the input material flows through a gasifier, it experiences several processes, including drying, pyrolysis, partial combustion and, finally, char gasification. At each of these stages, material properties change, either as density changes or chemical transformations, and there is a consequent need to process material of differing properties. Conventional methods primarily use gravity to direct material flow with no direct intervention or intervention methods that are quite different from those described herein. The active approach of the present disclosure as shown in FIG. 1 comprises at least one of: (i) method 15 which comprises an aliquot or batch method for processing solids flow through the gasifier; (ii) method 25 that utilizes material radial mixing without vertical displacement; (iii) method 35 that utilizes size particle selectivity for processing solids flow; and (iv) method 45 which uses a shock technique onto a grate assembly to effect material agitation. These anti-jamming methods may be used separately or in combination, and in particular sequences, to effect optimal particle transfer.
[0027] An implementation of these methods in a gasifier system is shown in FIG. 2 . Specifically, gasifier system 20 processes biomass 50 at one end of gasifier 40 and outputs char/ash 60 at the other end. Gasifer 40 has upright cylindrical walls 41 defining a biomass gasification chamber within, and has material presence sensors 61 , 62 , 63 and 64 attached to or within the walls that provide feedback on solids flow through the gasifier. Feedback information is fed to a processor 30 that controls the inflow system 110 , outflow system 160 , and agitation devices 120 , 130 , 140 , 141 and size selection device 150 .
[0028] FIG. 3 is a cross-sectional view illustrating a physical arrangement of gasifier elements in FIG. 2 . Specifically, FIG. 3 shows a three dimensional drawing of intake/outtake devices 210 and 260 , and agitation devices 230 , 238 , 240 , and 250 incorporated in a downdraft gasifier system 200 . System 200 has an intake auger 210 with gate valve that removes biomass from a reservoir (not shown). This biomass feeds into gasification chamber 225 that fills up to a preset level monitored by material presence sensor such as optical sensor or infrared sensors located within the chamber. The metered insertion of material implements aliquot distribution method 15 .
[0029] As the gasification process proceeds several zones of drying, pyrolysis, partial combustion and gasification are established. Agitation device 238 implementing method 25 is actuated by assembly 215 and is used to radially mix the gasification zone without disturbing the biomass, pyrolysis, or combustion zones. Agitation device 238 comprises a retractable shaft welded to an auger with large void volume. As material is gasified, it builds up a layer of char and ash. Depending on extent of gasification, material passes through displaceable grate assembly 250 , which is an implementation of method 35 . An agitation device 240 implementing method 45 is attached to grate assembly 250 and enables the transmission of hammer like impacts upon gasifier walls. This agitation device 240 also enables rotation of grate assembly 250 . Material exits through outflow assembly 260 which incorporates one or two gate valves and also implements aliquot method 15 . The components of this implementation by reference of the particular method represented will now be described.
[0030] Aliquot distribution method 15 comprises dispensing and removing metered amounts of material from the gasifier. Input biomass is dispensed into the gasifier using feedback from material presence sensors providing information on the amount and state of matter inside the gasifier. The material presence sensors provide input on such properties as the biomass fill level, biomass composition, biomass density and gasifier temperature and pressure. These material presence sensors can include capacitive sensors, mechanical displacement sensors, optical sensors, ultrasound sensors, infrared sensors, microwave sensors, X-ray sensors, thermal sensors, and pressure sensors providing input fed to a processor in order to facilitate material flow-thorough. Material is removed from a reservoir container system and deposited into the gasifier by various techniques, such as auger or belt transport, based on material presence sensor input identifying a need for more material. The reservoir system stores a volume of material that is significantly more than the amount of material in the gasifier at any one time. The advantage of this method is that it decouples the solids flow inside the gasifier from the input or output flow. An implementation of this method is shown in FIG. 4 and FIG. 5 .
[0031] Referring to FIG. 4 , input biomass is conveyed through auger 615 to tubular container 620 which is intercepted by gate valve 625 . This valve is a loadlock that opens to admit material in, but otherwise remains closed to exclude oxygen from the top of the gasifier. Optionally, a material presence sensor such as capacitive sensor 635 is provided to detect the presence or absence of biomass in tubular container 620 . The biomass fill level in the gasifier chamber is monitored by material presence sensors such as optical or infrared sensors 562 , 563 ( FIG. 5 ) which detect the presence of biomass indirectly (even in the presence of smoke) whenever sensor tip 564 is blocked. There may be a plurality of these sensors in the gasifier to gauge the fill level at several points.
[0032] FIG. 6B shows an embodiment with 3 material presence sensors, in which the lowest placed sensor 431 is activated under normal loads. When the biomass fill level is below this level, auger 615 is activated to input biomass until sensor 432 is activated, at which point the auger stops until sensor 431 is again activated. Sensor 433 can be used as a sensor that acts as an additional alarm. In this manner a consistent load is maintained. An additional advantage provided by this method is that multiple feeds are allowed at the same time. Thus different biomass feedstocks can be fed to the gasifier without affecting performance, due to the decoupling of the feed system to the gasification flow through.
[0033] The radial mixing without vertical displacement method 25 exerts minimal disturbance of the drying, pyrolysis, and combustion zones, while effecting radial mixing in the reduction zone. This is important for preventing premature mixing of the zones, as such a mixture can result in an explosive event. In a typical auger drilling operation, the rotation of the blade causes material to be removed out and upward of the hole being drilled. (See FIG. 6C ). In a gasifier with multiple zones, this simple drilling, while destroying bridging, would result upon retraction of the auger in a conduit which would allow hot gases to escape to the feed zone, leading to premature combustion. By contrast, the disclosed method destroys bridging without destroying gasifier performance. The method is implemented by agitation device 238 which comprises, as shown in FIG. 6B , open guide tube 425 , solid shaft 428 , and flattened wire 427 which spirals around solid shaft 428 . Shaft 428 is attached or welded to wire 427 only at select shaft protrusions, leaving significant void space between the shaft and the wire. This void space enables the assembly to be retracted while rotating in such a way that it does not remove material or intermix material between each zone. The void space also allows material to be radially mixed whenever the shaft rotates, thereby breaking the tar interface causing bridging. Material is stirred around, not up, as the drill rotates. The two extremes of position for the retractable assembly are shown in FIGS. 6A and 6B , and FIG. 6D shows the particle movement enabled by the the present invention in contrast to the upward particle shown in FIG. 6C for typical augers. Shaft 428 is driven by motor 605 via linkage 618 . as shown in FIG. 4 . Sealed housing 610 sits on top of the gasifier and is tall enough to provide room for the required vertical range of motion of agitation device 238 .
[0034] The solids flow method 35 uses particle size discrimination in processing material through the gasifier. This method selectively passes particles of a size or structure, such as ash or char particles, through an adjustable grate assembly and deters large size particles from passing through. The particle discrimination can be effected via different ways, such as a variable sieve assembly, a variable grate assembly, or other means able to control orifice dimensions for material exiting the gasifier. This particle discrimination allows control of material residence in the reduction zone, and can be used to control the ratio of carbonaceous material to syngas production. An implementation of this method is embodied in the variable grate assembly shown in FIG. 7 . A grate 330 with horizontal slots is housed near the bottom of gasifier standing on base 320 with legs 321 . Grate 330 sits on top of a similarly constructed grate (not shown) and is displaced relative to the bottom grate by servo mechanical means comprising motor 370 , gears 380 and 390 , and plunger 360 .
[0035] FIGS. 8A and 8B are perspective views showing grate positions achievable by servo control in the grate assembly. In particular, FIGS. 8A and FIG. 8B show the full range of relative motion of the grate assembly, wherein FIG. 8A depicts a fully open grate assembly which allows larger particle exit, while FIG. 8B depicts a minimally open grate assembly which preferentially admits fine particles.
[0036] The shock-prompted agitation method 45 is another method to break bridging that relies on hammer-like impacts to dislodge particles. This method may be combined with a method that rotates the grate mechanism, as shown in an implementation in FIG. 9 , which shows an embodiment using a cam driven grate assembly. With reference to FIG. 9 , cam 721 is driven by motor 701 and contacts cam follower 723 located on weight arm 722 . As the cam rotates it lifts the follower and weight arm against resistance provided by spring 712 whose resistance is regulated by motor 702 . As the cam rotates, the cam clears the follower and extension arm 724 impacts the plunger 713 which in turn imparts energy to the protruding arm 720 of rotatable grate 750 . On the opposing side of the protruding arm is another plunger which experiences a belt tension supplied by belt 725 and regulated by motor 703 . An illustration of the assembly range of motions is shown in FIGS. 10A, 10B, 10C and 10 D. FIG. 10A shows a belt in a relaxed position with the grate in an un-rotated state. In FIG. 10B , arm extension 722 has impacted the plunger, causing the grate to rotate about its principal axis and the opposing plunger to exert a force on belt 725 , as shown by deflection of the belt. Corresponding top views are shown in FIG. 10C and FIG. 10D , with FIG. 10D indicating a grate rotation by angle φ about the center gasifier axis, compared to FIG. 10C , which shows no rotation. The shock displacement method my be used in combination with the grate selectivity method to optimal particle flow. In the case of a fine powder biomass, for example, an approach utilizing high g-forces combined with restricted grate opening is preferable, whereas for large biomass particles such as walnut shells, a low g-force rocking motion in combination with wide grate opening would be optimal.
[0037] An additional anti-jamming method which comprises the present disclosure is vibrational excitation of gasifier walls. This method is implemented, as shown in FIG. 3 , via device 230 which comprises a small weight attached to a motor, in which the weight rotates off axis the principal motor rotation. This additional feature is particularly useful for removing bridging caused by very fine particles.
[0038] Material exiting the grate assembly drops onto exit auger assembly 260 which conveys the char or ash particles out of the gasifier. Generally, as shown in FIG. 11A , a loadlock such as gate valve 910 is used to exclude oxygen at this stage. If char is produced, it is desirable to include two gates valves, such as valves 940 and 950 , as shown in FIG. 11B , whereby a compartment 945 between the two gate valves serves as a holding container and insulates the gasifier from oxygen exposure. The char produced in this manner is made in a hydrogen rich environment, and is suitable for use as high temperature biocarbon fuel as disclosed in U.S. Provisional Application 62/288,605 titled “High Temperature Biocarbon Fuel”. The disclosed methods enable the production of a high temperature, high surface area, mechanically stable, long storage life, easily transportable biocarbon solid fuel of comparable energy density to liquid fuels.
[0039] The present disclosure also enables a fast start-up in the gasifier with consequent hydrogen production.
[0040] One skilled in the art will appreciate that the present disclosure can be practiced by other than the various embodiments and preferred embodiments, which are presented in this description for purposes of illustration and not of limitation, and the present disclosure is limited only by the claims that follow. It is noted that equivalents for the particular embodiments discussed in this description may practice the disclosure as well.
[0041] While various embodiments of the present disclosure have been described above, it should be understood that they have been presented by way of example only, and not of limitation. Likewise, the various diagrams may depict an example architectural or other configuration for the disclosure, which is done to aid in understanding the features and functionality that may be included in the disclosure. The disclosure is not restricted to the illustrated example architectures or configurations, but the desired features may be implemented using a variety of alternative architectures and configurations. Indeed, it will be apparent to one of skill in the art how alternative functional, logical or physical partitioning and configurations may be implemented to implement the desired features of the present disclosure. Also, a multitude of different constituent module names other than those depicted herein may be applied to the various partitions. Additionally, with regard to flow diagrams, operational descriptions and method claims, the order in which the steps are presented herein shall not mandate that various embodiments be implemented to perform the recited functionality in the same order unless the context dictates otherwise.
[0042] Although the disclosure is described above in terms of various exemplary embodiments and implementations, it should be understood that the various features, aspects and functionality described in one or more of the individual embodiments are not limited in their applicability to the particular embodiment with which they are described, but instead may be applied, alone or in various combinations, to one or more of the other embodiments of the disclosure, whether or not such embodiments are described and whether or not such features are presented as being a part of a described embodiment. Thus the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.
[0043] Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term “including” should be read as meaning “including, without limitation” or the like; the term “example” is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; the terms “a” or “an” should be read as meaning “at least one,” “one or more” or the like; and adjectives such as “conventional,” “traditional,” “normal,” “standard,” “known” and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, where this document refers to technologies that would be apparent or known to one of ordinary skill in the art, such technologies encompass those apparent or known to the skilled artisan now or at any time in the future.
[0044] A group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should also be read as “and/or” unless expressly stated otherwise. Furthermore, although items, elements or components of the disclosure may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated.
[0045] The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. The use of the term “module” does not imply that the components or functionality described or claimed as part of the module are all configured in a common package. Indeed, any or all of the various components of a module, whether control logic or other components, may be combined in a single package or separately maintained and may further be distributed across multiple locations.
[0046] Additionally, the various embodiments set forth herein are described in terms of exemplary block diagrams, flow charts and other illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives may be implemented without confinement to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration. | A method is described for processing biomass using a series of mechanisms that operate in unison to maintain solids flow through small gasifiers that are otherwise prone to blockage. An automated system that implements these methods is also disclosed. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to methods of promoting the growth of plants and in particular it relates to methods for increasing the yield of fruit production of plants. In another aspect, the invention relates to increasing the rate of growth of legumes and yields of edible reproductive fruits of said legumes. In still another aspect, the application of effective amount of the vanadyl compositions applied to plants during growth cycles has been found to promote plant growth and plant fruit yield in peanuts, a legume.
Worldwide increasing population increases demands on horticulture efficiency and agricultural crop yields from all sources. The need to improve these efficiencies and yields is ever present especially in view of the loss of productive farm land. Thus, improved plant growth and plant fruit yields and quality are needed along with better utilization of agricultural lands in order to meet the increasing population growth food requirements. Plant growth regulators which can economize the use of fertilizers, nutrients, enzymes, and other growth promoters for various plants are being investigated continuously. Unfortunately, plant growth regulators and specific species of plants along with different generic classes of plants provides the researcher with less than predictable results even when utilizing same or similar compounds successfully applied to other species and generic classes.
Plant growth regulators can be defined as compounds and preparation which in minute amounts alter the behavior of crop plants or the produce of such plants through physiological (hormonal) tendencies rather than physical action. Plant growth regulators may either accelerate or retard growth, prolong or break a dormant condition, promoting rooting, fruit-set, or increase fruit size or quantity, or effect a growth and or productivity of plants in other ways. Plant growth regulation activity can vary from plant to plant as well as from novel composition to novel composition and specific combinations of the compositions and plants.
Various compositions have been studied as micro nutrients and plant growth promoters to increase crop productivity across a wide range of horticulture and agricultural crops. Compositions which include vanadium compounds have been studied and have results both beneficial and detrimental in effect on plants. Vanadium occurs in higher plants at levels usually between 0.2 and 4 ppm. Studies indicate that vanadium may have some effect on plants, including higher order plants which are of agricultural interest. Whether that effect is beneficial or detrimental appears to depend on the form of the vanadium, the type of plant and the method and timing of the application.
The importance of many metallic elements as integral constituents of enzymes and electron carriers warrants the attention of many plant physiologists. Aside from their roles as cofactors, activators are regulators in many enzymes' reactions, trace elements are essential to the maintenance of many biochemical processes in plants. Vanadium is one of the trace elements that is widely distributed in plants. Despite the fact that has been shown that vanadium increases growth in lettuce, tomatoes, asparagus, corn, barley and rice and the like, there is still no conclusive evidence that it is an essential element for higher plants. It does not meet the criteria of essentiality to the plant. However, vanadium on the other hand appears to be essential for many microorganisms. Continuing studies are being undertaken presently as they have in the past to investigate the distribution of vanadium and its effects on growth of agriculturally useful plants. Vanadium has stimulated growth and mazed plants at levels of 0.25 ppm in nutrient solutions. However, vanadium had no effect on lettuce or tomato plants at levels of 0.05 ppm. Lauchili et al. 15B ENCYCLOPEDIA OF PLANT PHYSIOLOGY 723-26 (1983). A study of the effect of a foliar spray of a vanadyl sulfate solution on leaf growth of sugar beet plants indicated that it decreased leaf growth, but that it increased the amount of reducing sugar in the roots of the sugar beet. Singh et al. 44 PLANT PHYSIOLOGY 1321-27 (1969). The use of vanadium (in the form of vanadyl lactate at concentrations of 10 -3 to 10 -6 molar) as a fertilizer has produced an increase in foliage yield of some higher plants. Kerr et al. Monograph 11 BRITISH PLANT GROWTH REGULATOR GROUP 103-21 (1984).
More recently vanadyl composition have been used in promoting the lint yield of fiber producing plants such as cotton by heating the plant during growth periods of the plant with an amount of a vanadyl salt of a carboxycilic acid. These compositions are found in U.S. Pat. No. 5,186,738 hereby incorporated by reference; however the '738 patent reports that the vanadyl composition proved ineffective for promoting the growth of soybeans, a legume. Again illustrating the variations of experience with vanadyl compositions in achieving regulation activity ie. plant growth and plant fruit growth enhancement from plant to plant. Thus, a continuing need exists for development of effective vanadium composition methods, timing and conditions of application in order to achieve enchanced edible fruit production.
SUMMARY OF THE INVENTION
The invention provides novel methods for enhancing the growth of plants and fruits produced by such plants through contacting the plants during growth periods with effective amounts of vanadyl compositions. The invention also includes effective methods for applying the vanadyl compositions to plants to promote growth and fruit yields. These methods include composition's application rates, time of application and other plant conditions such as stress, moisture levels and the like in order to achieve enhanced fruit yields. The vanadium compositions specifically vanadyl ions have been effective on the plant growth, particularly plant fruit growth such as the edible fruits of legumes. Preferably, the vanadium compositions which are applied to the plants, influence the plants as vanadyl ions and one source of such compositions is the vanadyl salt of a carboxylic acid such as vanadyl lactate or vanadyl citrate. The plant may be treated by supplying the plant measured amounts of vanadyl compositions to the foliage of the plant or to the roots of the plant or a combination of both. Applying the roots of the plant is accomplished by applying the compositions to earth around the plant or irrigating the roots of the plant with the application in combination of water. In addition, the applications can be, by applying dry composition powder to the foliage of the plant which followed by rain, irrigation and the like, assist the plant in absorbing the vanadyl composition ions. Using one or more of these methods, the application of the composition is applied at least once during growth periods of the plant. Generally, the application of the composition is applied only once during the growth period of the plant preferably under moist conditions. The compositions are applied to achieve a treatment rate ranging from about 0.025 lbs per acre to about 0.1 to 0.2 lbs per acre of growing plants. In the case of peanuts, the application of 0.05 lbs per acre at the peg stage of growth increased peanut yields of at least about 5 percent by weight.
For fruit bearing plants including fruit bearing legumes, the application of the composition is applied to the plant from about 21 days before the start of the reproductive cycle of the plant to about 21 days after the start of the reproductive cycle of the plant. The start of the reproductive cycle of the plant is indicated by settling of blooms or similar states depending on the type of plant.
In one embodiment, the application form of the composition is an aqueous solution or emulsion which contains an effective concentration of vanadyl ions. The solution is prepared by dissolving, for example, an organic compound or a complex of vanadium in water which provides a source of vanadyl ions. The solution is then sprayed onto the foliage or leaf surfaces of the plants during the growth period of the plants and under preferably moist conditions.
The application form on the composition can be in solid, particular or powder form which includes an organic compound or complex of vanadium and is applicable to the earth around the plant. The solid composition particulate materials are applied by spreading around the plants during the growth period. The action of irrigation water or rain then causes the solid particles to dissolve and generates a solution which has an effective concentration of vanadyl ions. The aqueous solution flows into the ground around the roots of the plant and irrigates the roots of the plant.
The compositions of the invention and methods of applications of applying these compositions are particularly useful for promoting the growth of plant produced fruits. Specifically edible reproductive fruits of plants ie. legumes which are valuable and necessary food as well as other potential agronomic crops which may be shown to be influenced in plant growth enhancement and fruit yield.
DETAILED DESCRIPTION OF THE INVENTION
The invention provides a method for increasing the rate of growth of plants and yields of edible reproductive fruits of said plants achieved by supplying to the plants which produce edible reproductive fruits on at least one occasion during growth cycles of the plant, an effective amount of vanadyl ions. The method of this invention can be employed to increase vegetative growth and to increase fruit production of fruit producing plants. The vanadium composition used in the methods of this invention have broad spectrum plant growth regulation capacity that can be employed to stimulate the growth and/or fruit-producing capability of plant varieties, including fruiting and princibly vegetative plants. Fruiting plants, for the purpose of the invention include plants that bear any variety of produce other than vegetative growth such as annual or perennial vegetables, fruits, nuts and the like. Varieties of vegetables which can be treated in accordance with the methods of the invention include bulb plants such as onions, tuberous crops such as potatoes, sugar beets and peanuts (legumes), beans, peas and the like. Treatable nut crops include walnuts, pecans, almonds, cashews and the like can also be enhanced.
Vanadium is a transition metal which displays well-characterized valence states of +2 through +5 in solid compounds and in solution. Vanadium easily forms oxycations such as vanadyl ions (VO) 2+ which are composed of vanadium metal and oxygen. The valence state of vanadium in a vanadyl ion is +4. Many compounds or complexes which include vanadium may be used to generate the vanadyl ions.
For example, vanadium forms compounds or complexes with various organic compounds such as carboxylic acids. Carboxylic acids are characterized as organic compounds that contain at least one carboxyl group. The carboxyl group is represented chemically as: ##STR1## where R is a saturated or unsaturated organic group which includes one or more carbons.
Formic, acetic, propionic, and butyric acid are examples of carboxylic acids which contain one carboxyl group and form compounds or complexes with vanadyl ions. Likewise, oxalic, malonic, succinic, glutaric, adipic, maleic, and fumaric acid are examples of dicarboxylic acids which contain two carboxyl groups and form compounds or complexes with vanadyl ions. Further, other carboxylic acids with one or more carboxyl groups such as glycolic, lactic, glyceric, citric, tartaric, and malic acid form compounds or complexes with vanadyl ions. Organic compounds or complexes of vanadyl ions may also occur in polymeric form. The term "carboxylic acid" as used herein means any organic compound which includes one or more carboxyl groups, and specifically includes the compounds noted above.
Other compounds or complexes which contain vanadyl ions may also be used in the compositions of the invention. For example, a diketone such as acetylacetone forms vanadyl acetylacetonate which may be used in the compositions of the invention.
Some vanadium compounds are ineffective for promotion of plant growth, especially plant fruit growth. For example, vanadate compounds which generate the vanadate ion (VO 2 )+ in which vanadium has a +5 valence state have been found to be detrimental to plant growth.
The compositions of the invention may be prepared in concentrate form or application form. For example, the composition may be made in solid particulate form which may be bagged and easily transported to a desired plant crop location. At the plant crop location the solid form may be mixed with water to create a solution which may be sprayed onto the foliage of plants. The solid particulate form of the composition may include an organic compound or complex of vanadium which may generate vanadyl ions when dissolved in the water. The solid particulate form would also include a conventional agricultural carrier agent in solid form.
Conventional liquid agricultural carrier agents may also be used in the various forms of the composition. Generally, the organic compound or complex of the vanadyl ions will be dissolved or dispersed in the liquid carrier agent. Preferably, water is used as the liquid carrier agent. Other conventional agricultural oils may also be used as the liquid carrier agent. For example, a liquid concentrate form of the composition may be prepared by dissolving or dispersing an amount of an organic compound or complex of vanadyl ions in water. The liquid concentrate is then containerized and transported to a plant crop location and mixed with more water to prepare an application form of the composition with an effective concentration of the vanadyl ions in solution. The application form of the composition is then sprayed onto the foliage of the plants.
Generally, the vanadyl ion compositions of the invention has potential for application to any type of plant to promote growth. The term "promote growth" means improving the number, size, quantity, or quality of fruits that grow on the plants. The term "promote growth" also encompasses characterizations of the effect of the composition on plants such as yield enhancer, fertilizer, and micro-nutrient. Plant fruit in this context includes any seed bearing organ of a plant such as beans, tublers, bulbs, peas and the like. The vanadyl ion compositions additionally improve the water and nutrients use efficiency of plants as one aspect of promoting the growth of the plants.
Other ingredients may be added to the composition to produce specific effects. For example, adhesives, thickeners, penetrating agents, spray oils, stabilizers, preservatives, surfactive agents, fertilizers, micronutrients, pesticides may be added to the composition as desired.
The vanadyl ion composition is applied to the plant during the growth period of the plant. The time and number of applications of the composition are dependent upon the type of the plant and the desired effect. For example, to promote fruit growth, the composition should be applied during the time period from shortly before the start of the reproductive stage of the plant to shortly after the start of the reproductive stage of the plant. The start of the reproductive stage of the plant is characterized by the setting of blooms, or a similar stage indicating the beginning of the fruit depending on the type of plant.
Preferably, the vanadyl ion composition is applied between about 21 days before the start of the reproductive stage of the plant to about 21 days after the start of the reproductive sage of the plant. For cotton, the preferred application time period is from 14 days prior to the setting of blooms to 7 days after the setting of the blooms. For any particular plant the optimal time for applying the vanadyl ion composition within the period of 21 days before to 21 days after the start of the reproductive stage may be determined using conventional techniques.
Different methods may be used to apply the vanadyl ion compositions to plants. For example, a liquid form of the composition may be applied to the leaves or foliage of plants. This may be accomplished using conventional agricultural spray devices. Both liquid and solid forms of the composition may be applied to earth surrounding plants. For example, conventional watering systems may be used to apply a liquid form of the composition to earth around plants. Further, the composition may be applied to the roots of the plants. For example, the liquid form of the composition may be injected into the ground around the roots of the plants by using underground pipes or hoses.
To maintain the vanadyl ions in the liquid form of the composition, it is necessary to control the pH of the composition. Otherwise the vanadyl ions might be converted to other noneffective vanadium ions such as vanadate ions. Generally, the application form of the composition should be maintained at a pH ranging from about 4 to 9 to maintain the vanadyl ions. Preferably, the pH is maintained in the range of about 6 to 8. Depending on the ingredients in the composition, the pH may be controlled by adding a buffering agent.
The following examples were based on the application of 0.05 lbs of vanadium compound per acre to peanuts at the peg stage of growth and are compared to control plots in the same field.
EXAMPLE 1
Vanadyl composition, a vanadyl salt of a carboxylic acid such as vanadyl lactate or vanadyl citrate, were applied to peanut plants at the peg stage of growth under moist conditions in a 20 acre plot of a total 60 acre field of peanuts. The entire 60 acres of peanuts being planted, cultivated, fertilized and irrigated under exactly the same conditions which allowed for direct comparisons of the yields of the treated peanuts ie. 20 acres versus the control 40 acres. The treated acreage of 20 acres of peanuts provided a yield of 5,197.30 lbs per acre while the control acreage (40 acres) yielded 4,815.35 lbs per acre. The vanadium treated peanuts produced a 7.9 percent increase in peanuts ie. fruit yield. Application date was on Aug. 3 at 8 am and was delivered by air means under moist conditions, plant moist conditions ie. moist foliage conditions.
EXAMPLE 2
A 120 acre field of peanuts was divided into a 20 acre plot wherein vanadyl composition vanadyl salt of a carboxylic acid such as vanadyl lactate or vanadyl citrate applications were made to the peanuts versus a control of 100 acres of peanuts. The entire 120 acres of peanuts being planted, cultivated, fertilized and irrigated under the same conditions which allowed for direct comparisons of the yields of the peanuts ie. 20 acres versus the control 100 acres. The treated peanuts yield 3,518.20 lbs per acre (20 acre plot) and the control peanuts (100 acres) yielded 3,117.16 lbs per acre. The application date was Aug. 3, 1993 at 8:10 am by air means when the peanut plants foliage was in a moist condition.
Overall the test plots were visually impressive. A visual difference existed between the treated and untreated plants. The treated peanuts had a darker green color and seemed to be in a more healthy growth mode. The peanuts at harvest time on the vanadium treated plants were positioned in a tight ball around the roots instead of being more scattered out on the vine. The pods also seemed to be more completely filled. The treated peanuts looked more mature. However, this observation was not reflected in the grade.
In Example 2, the greatest difference in appearance and yield was observed. The peanuts went through a great deal of stress mainly yellow herbicide damage as compared to the peanuts of Example 1. The treated vines were not as stunted at harvest as the untreated. The USDA grade sheets, however, produced no differences in grade between the treated and the untreated. From the results, vanadium compositions and the respective applications of these compositions is very desirable as to the yields of produced fruit (peanuts) and are most cost effective for the increased yields.
The application of vanadium compounds to other crops frequently fails to show significant results from the treatments. Most of these crops tested have been during unusual weather years, causing poor crop stands that give mixed results. The effectiveness of vanadium composition treatment on enhanced growth and plant fruit yields of other crops is still to be determined based on application rates and conditions of applications. What here before has been reported as inconclusive or negative results may, with additional exploration of conditions, application rates and timing of applications, produce similar improved results with vegetable such as onions, potatoes, carrots, beans, peas and the like.
Useful vanadyl compositions can be prepared by four to five multiration of lactic acid added to a solution of vanadium pentoxide in a working volume of water. The working volume of water will be dependent upon the amount needed to prepare the overall solution. The mixture of lactic acid, vanadium pentoxide and water is stirred and heated as a result that the vanadium pentoxide and lactic acid react to farm vanadyl lactate in its ionic form which includes vanadyl ions. The vanadyl ions will be characterized by dark blue color in the solution. The pH of the solution will be acidic due to the lactic acid and the pH should be adjusted to approximately neutral for dilution and addition to respective plant foliage or at root systems.
The examples and embodiments described above illustrate the invention and changes in modifications can be made without departing from the scope of the invention. It is intended that such changes modifications fall within the scope of the invention as defined by the appended claims. | A method for enhancing the growth of plants and fruits produced by such plants through contacting the plants during growth periods with effective amounts of vanadyl compositions. These methods include composition's application rates, time of application and other plant conditions such as stress, moisture levels and other growth variables in order to achieve enhanced fruit yields. | 0 |
The present application is a continuation of application Ser. No. 500,376, filed June 2, 1983, now abandoned, which is a division of application Ser. No. 286,365, filed July 23, 1981, now U.S. Pat. No. 4,424,951, which is a continuation-in-part of application Ser. No. 197,085, filed Oct. 15, 1980, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to building forms and, more particularly, to metallic forms for making concrete columns, walls, and similar structures.
2. Description of the Prior Art
Concrete columns, such as the type used as supports for buildings, bridges, and the like are made by pouring concrete into a form comprising a plurality of stacked, attached, hollow metallic form units. Each unit is made of half-sections which are attached to each other at their vertically aligned joints by a plurality of fasteners spaced about a foot apart. Since the form assemblies can vary from four to 20 or more feet in height, a considerable number of fasteners are required to be inserted each time an assembly is made. After the concrete has hardened, the fasteners are then removed one by one so that the section halves can be parted from the concrete and moved to a new location for reassembly to provide a form for the next column to be poured. The process of attaching and removing the individual fasteners is time-consuming, results in extensive labor costs, and the materials used in the fastening process, such as nuts and bolts, are easily lost.
While various "quick release" techniques employing elements such as pins, wedges, sliding fasteners, and the like have been used to secure section halves in place, they have had the disadvantage that they still have to be individually removed and replaced, thereby requiring extensive manual labor. In addition, some of the devices have had a problem in achieving a desired positive lock of the forms in place.
SUMMARY OF THE INVENTION
For purposes of simplicity, the invention will be described as employed in the manufacture of concrete columns, although it will be understood that the invention is equally applicable to other concrete structures such as walls, caps, beams, and the like. In accordance with the present invention, a form into which concrete may be poured to form a column includes a plurality of stacked form units having interconnected expandable and contractible joints. The application of a vertically upward force to the joints of the uppermost form unit causes all the units to move together, first outwardly from the column and then upwardly, to strip the form from the column. The form thereafter may be moved to another location where the joints of the form units may be contracted to provide a form for pouring another column.
In a preferred embodiment, the joints are disposed on opposite sides of the form units, and each joint includes movable portions which are cammed outwardly or inwardly, depending on the direction of vertical movement of a central, vertically movable portion. The camming action occurs by the action of cams carried by the vertically movable portion urging cam followers mounted on the movable portions to move side members of the form units away from the column when the form is being stripped from the column, and to urge the side members inwardly when the form is being moved to a position where another column is to be poured, whereby the cams hold the joints closed in preparation for pouring of the next column.
The form according to the invention eliminates the need to remove a plurality of fasteners from each form unit prior to removal of the form from the column, and it also eliminates the need to reinsert a plurality of fasteners in the form units to reassemble the form. Instead, the form can be stripped from the column and reassembled in the next location primarily by the action of a lifting mechanism such as an erecting crane. Not only is such an operation accomplished at a great reduction in manual labor, but the loss of fasteners is greatly reduced or eliminated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one form unit made in accordance with the present invention;
FIG. 2 is an elevational view of a form employing form units of the type of FIG. 1, with the form erected and concrete poured;
FIG. 3 is a schematic plan view of the form of FIG. 2;
FIG. 4 is a schematic plan view of the form of FIG. 2 illustrating a separation of the form from the column at the start of a stripping action;
FIG. 5 is a front elevational view showing the form of FIG. 2 being partially stripped from the column by the application of an upward force;
FIG. 6 is a perspective view of the connection between vertically movable panels of superimposed form units;
FIG. 7 is an enlarged, fragmentary, partially broken away, cross-sectional view of the near corner of the form of FIG. 2;
FIG. 8 is an enlarged, fragmentary, partially broken away, cross-sectional view of the near corner of the form of FIG. 5;
FIG. 9 is a partially broken away, fragmentary, front elevational view of the movable joints of one corner of a form according to the invention taken generally along a plane indicated by line 9--9 in FIG. 7, showing vertically movable joint panels in a downward position, and laterally movable panels in a closed position prior to the pouring of concrete;
FIG. 10 illustrates the joints of FIG. 9, but with the vertically movable panels being raised to a point where the leading edges of cams have just engaged the leading edges of cam followers at the commencement of a laterally outward camming action;
FIG. 11 illustrates the joints of FIGS. 9 and 10, but with the vertically movable panels having reached the point where the laterally outward camming of the laterally movable joint panels is completed;
FIG. 12 is a vertical section taken along a plane indicated by line 12--12 in FIG. 8;
FIG. 13 is a fragmentary cross-sectional view taken along a plane indicated by line 13--13 in FIG. 9, showing a removable fastener for the bottom of the form, with the fastener in position prior to the pouring of concrete;
FIG. 14 is a fragmentary schematic view of a portion of a modification of the present invention as applied to a form unit having curved walls, and showing a movable joint in a contracted position;
FIG. 15 is a view of the joint of FIG. 14 in an expanded position;
FIG. 16 is a fragmentary, schematic view of a modified cam and cam follower;
FIG. 17 is a front elevational view of a portion of a form unit showing a modified arrangement of a forceapplying mechanism, with the solid lines illustrating the form unit in a partly closed position, and the phantom lines showing the form unit in a fully closed position;
FIG. 18 is a side elevation view of the arrangement shown in FIG. 17 with the form unit in the partly closed position;
FIG. 19 is a side elevational view of the arrangement shown in FIG. 17, with the form unit in the fully closed position;
FIG. 20 is an enlarged view taken along a plane indicated by line 20--20 in FIG. 17;
FIG. 21 is a schematic plan view of another form according to the invention;
FIG. 22 is a schematic plan view similar to FIG. 21 illustrating a separation of the form from a concrete structure at the start of a stripping action;
FIG. 23 is a perspective view of the form of FIGS. 21 and 22, with portions broken away and removed for clarity;
FIG. 24 is an enlarged sectional view of a movable joint connecting portions of the form of FIG. 23;
FIG. 25 is a partially broken away view of the movable joint of the form of FIG. 23 taken along a plane indicated by line 25--25 in FIG. 24, showing a vertically movable member in a lowered position, and a movable wall in a closed position; and
FIG. 26 illustrates the movable joint of FIG. 25, but with the vertically movable member in a raised position and the movable wall in an open position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the various Figures, a form unit 1 having sides 22, 23, 24, 25 defines an internal cavity 16 into which castable material, such as concrete, is to be poured, to assume the shape of the cavity 16 upon hardening. In the description that follows, use of a prime mark (') and the use of a double-prime mark (") indicates that a given element used in a given form unit is also used in vertically adjacent form units 1; likewise, use of the designations "A" and "B" indicates that substantially identical form units 1 are being used. In accordance with the invention, the unit 1 has oppositely disposed expandable and contractible joints 3 and 4 which movably connect one side member, such as half-section 20, to another side member, such as half-section 21. Each movable joint 3 and 4 includes a vertically movable member, such as panel 5, having a plurality of cam means, such as cam pairs 8, 8' and 8" which engage a plurality of cam follower means, such as cam followers 9, 9' and 9". The cams 8, 8', 8" and the cam followers 9, 9', 9" interact to move laterally movable members, such as horizontally movable panels 6 and 7 (FIGS. 7 and 8), laterally outwardly or inwardly, away from or towards each other, so as to expand or contract the joints 3 and 4 and thereby open or close the form unit 1.
A plurality of the form units 1 may be stacked and connected to each other to provide a multi-unit form 2 by fastening together upper flanges 26 of a given form unit 1 to lower flanges 27 of a superimposed, comparable form unit 1. Form units 1, 1A and 1B in FIG. 2 have been connected in this manner. The vertically movable panel 5 of each form unit 1 also includes lower channel arms 12 adapted to engage an upper tongue 14 included as part of the panel 5 on a vertically adjacent form unit 1. By this construction, panels 5, 5A and 5B of superimposed form units 1, 1A and 1B are interconnected as at 10 and 10A to be simultaneously vertically movable.
In operation, the form 2 is erected as shown in FIG. 2 and concrete is poured to fill the form 2. After the concrete has hardened to form a column (FIG. 3), crane hooks 15 from a crane (not shown) then are applied to the tongues 14 of the joints 3 and 4 of the uppermost form unit 1B. The hooks 15 then are pulled upwardly by the crane in a continuous motion. Such movement, due to the camming action of cams 8, 8', 8" on cam followers 9, 9', 9", first causes the form halves 20, 21 of each unit 1, 1A, 1B to move laterally outwardly to the position of FIG. 4, breaking the contact between the form units 1, 1A, 1B and the column. As shown in FIG. 5, continued upward movement of the hooks 15 then causes the units 1, 1A, 1B to move upwardly and to be stripped from the column. At a new location (not shown), the form 2 can be lowered into place, and the various components of the form 2 will reassume the position shown in FIG. 2. More concrete can be poured into the form 2 to create a new column.
The shape of the form units 1 for use in the present invention will vary with the cross-sectional shape of the column to be formed--such as, for example, round or square. For purposes of illustration, the application of the present invention to a column having a square cross-section will be described in detail. As shown in FIG. 1, the unit 1 comprises a pair of half-sections 20, 21. The first half-section 20 includes a pair of metallic sides 22, 23 fixedly joined at terminal flanges 61, 62 by an angle iron 63 and fasteners 64, as is conventional in the art. The second half-section 21 similarly includes a pair of metallic sides 24, 25 connected at terminal flanges 65, 66 by an angle iron 67 and fasteners 68. Each of the sides 22, 23, 24, 25 has an upper flange 26 and a lower flange 27 whereby the form units 1 can be secured to each other in vertically stacked alignment by the use of fasteners 69, as is known in the art. The section halves 20, 21 are movably joined to each other at opposite corners of the form unit 1 by expandable and contractible joints 3, 4.
Joints 3 and 4 are identical, and thus the structure of only one of them will be described. FIG. 7 illustrates in detail the construction of the joint 3 and its mounting between flanges 31, 32 projecting outwardly of sides 23, 25, respectively. The securement of the joint 3 to the flange 31 is made by a first support plate 40 which is attached to the flange 31 by a plurality of fasteners 36. Similarly, the joint 3 is attached to the opposite flange 32 by a second support plate 41 which is attached to the flange 32 by a plurality of fasteners 37. A first, laterally movable panel 6 is secured to the first support plate 40 by an angle iron 43, a plurality of tab projections 46, and a plurality of weldments 48. Similarly, a second, laterally movable panel 7 is secured to the second support plate 41 by an angle iron 44, a plurality of tab projections 47, and a plurality of weldments 49. By the foregoing construction, the panels 6, 7 will move apart when the form 2 is being stripped from a solidified column, and the panels 6, 7 correspondingly will urge the sides 23, 25 to which they are attached to move away from the column as shown in FIGS. 4 and 8.
FIG. 7 also shows the mounting of the vertically movable panel 5 relative to the laterally movable panels 6, 7 within the joint 3. The panel 5 has a width equal to approximately the combined width of panels 6 and 7, and is mounted for slidable movement within a vertical channel 35. The channel 35 is defined generally by a plurality of bracket arms 51, 52 projecting from angle irons 43, 44, and which are welded thereto, as by weldments 73. A plurality of cams 8 are attached to the panel 5 by fasteners 38 and provide a vertically sliding engagement between the panel 5 and the confronting faces of the panels 6, 7. A plurality of cam followers 9 are attached to the panels 6, 7 by fasteners 39 and provide a means to interact with predetermined ones of the vertically movable cams 8. As shown in FIGS. 9-11, and as described in more detail hereafter, panels 6 and 7 are cammed laterally outwardly as the panel 5 is moved vertically upwardly.
FIG. 9 shows the mounting of the cams 8, 8' and the cam followers 9, 9' in more detail. While only two cam pairs 8, 8' and two cam follower pairs 9, 9' are shown, it is to be understood that the form 2 in practice will include additional cams and cam followers that operate comparably to those shown. It is preferred that cams 8 and matching cam followers 9 be disposed about every foot in the vertical height of the form 2. For clarity of illustration, a portion of the vertically movable panel 5 is cut away to better show the inter-relationship of the representative cams and cam followers.
As shown in FIG. 9, the cams 8, 8' and the cam followers 9, 9' are mounted so that when the panel 5 is in a lowered position, the panels 6, 7 are in a closed position. The cams 8, 8' are disposed laterally outwardly of the corresponding cam followers 9, 9'. The cams 8, 8' and the cam followers 9, 9' are angled from the vertical to define a generally upwardly facing wedge shape. When the panel 5 is moved upwardly, the cams 8 will move upwardly and inside of the immediately vertically adjacent cam followers 9' so as to cam the panels 6, 7 laterally outwardly. Similarly, when the panel 5 is moved downwardly when the form 2 is positioned at the next location for pouring a column, the cams 8 will be realigned outside of, and in engagement with, the immediately vertically adjacent cam followers 9 so as to cam the panels 6, 7 laterally inwardly. Accordingly, the joint 3 will be closed during the pouring of the concrete.
In order to facilitate the initiation of the camming action, the cams 8, 8' and the cam followers 9, 9' include tapered top and bottom surfaces 53, 54, respectively, which engage each other obliquely at the start of the camming action. It is preferred that the top and bottom surfaces 53, 54 define the same angle with respect to the vertical, and that such angle be between 35 and 40 degrees. This will provide a sufficiently rapid outward movement of the plates 6, 7 to break the seal between the column and the sides 22, 23, 24, 25 of the form 2. The camming action is then completed by contact between laterally outwardly facing camming surfaces 55 of the cams 8 and laterally inwardly facing camming surfaces 56 of the cam followers 9'. It is preferred that the camming surfaces 55, 56 define the same angle with respect to the vertical, and that such angle should be between 8 and 10 degrees. This will provide sufficient laterally outward movement of the plates 6, 7 to achieve sufficient clearance between the column and the sides 22, 23, 24, 25 to permit the form 2 to be lifted from the column.
The cams 8, 8' include bottom surfaces 57 and the cam followers 9, 9' include top surfaces 58 to facilitate camming contact when the panel 5 is moved downwardly into the closing position. It is preferred that the bottom and top surfaces 57, 58 define the same angle with respect to the vertical, and that such angle be between 35 and 40 degrees. This will provide sufficient laterally inward force on the plates 6, 7 to initiate the closing process. The camming action then is completed by contact between laterally inwardly facing camming surfaces 59 of the cams 8, 8' and laterally outwardly facing camming surfaces 60 of the cam followers 9, 9' which provide the means to cam the panels 6, 7 together as the panel 5 descends. The surfaces 59, 60 are generally parallel to the previously described camming surfaces 55, 56.
A stop plate 17 is provided toward the bottom of the form 2. The stop plate 17 is spaced a predetermined distance from the adjacent bracket arms 51, 52, whereby the engagement of the stop plate 17 with the lowest of the bracket arms 51, 52 will prevent further upward movement of the panel 5, and thus prevent further lateral movement of the panels 6, 7. When vertical spacing between the cams 8, 8' is about one foot, the preferred spacing of the stop plate 17 from the lowest bracket arms 51, 52 is about nine inches.
In order to secure the vertically sliding panels 5, 5A, 5B together so that they may move as a unit when a vertical force is applied, a locking arrangement is provided as shown generally at 10 and 10A in FIGS. 2 and 6. The locking arrangment 10, 10A is provided by a channel formed by a pair of projecting arms 12 located at the bottom of each of the plates 5, and a tongue 14 located at the top of each of the plates 5. The arms 12 and the tongues 14 interfit when the form units 1 are stacked atop each other. The arms 12 and the tongues 14 each have an opening as indicated at 29 which register to provide a passageway for receiving a detachable fastening pin 50. The pin 50 may be secured to the panel 5 by a chain 35 to prevent the pin 50 from becoming lost.
The tongues 14 also can provide a means of securing the crane hooks 15 to the plate 5B of the uppermost form unit 1B. While the hook 15 is shown attached only to the tongue 14 of the joint 3, it will be understood that a similar hook 15 will be attached to the tongue 14 of the joint 4. In addition, it may be desirable to attach additional hooks directly to the sides 22, 23, 24, 25 to provide sufficient force for lifting the form 2 vertically after the raising of the panel 5 has brought about the lateral separation of the form units 1 from the column.
Safety chains 97 may be connected to the brackets 51, 52 to assist the stop plate 17 in limiting outward movement of the panels 6, 7. The chains 97 provide a slack portion when the panels 6, 7 are closed, and move outwardly to check lateral movement when the panels 6, 7 are opened.
In order to assist in the closing of the panels 6, 7, springs such as 33 may be attached between the bracket arms 51, 52. An additional technique for causing the complete closure of the panels 6, 7 is illustrated in FIGS. 17-20. These Figures illustrate an arrangement for utilizing power means to force a closure of the panels 6, 7 in the event that forces greater than that exerted by the springs 33, by gravity acting on the panel 5, or by manual pressure acting on the panel 5 are necessary. Such arrangement comprises a jack 80 which may be manually operable and which is so positioned as to exert a downward force against the panel 5 so as to cause the panels 6, 7 to be cammed towards each other to move the form halves 20, 21 to the closed position. The downward force required to close the form halves 20, 21 will vary with the height and weight of the form halves 20, 21, and with the coefficient of friction between the bottom surfaces of the form halves 20, 21 and the top of the supporting surfaces. The jack 80 includes a cylinder 81, the base 82 of which is supported upon a pad 83. The jack 80 also includes a piston 84, the head 85 of which engages a pad 86. The pad 83 is affixed to a pair of the arms 12 connected to the panel 5. The pad 86 forms the base of an angle bar 87, the vertical face 88 of which extends laterally between, and is carried by, the angle bars 43, 44. The face 88 has a slight clearance with the panel 5, as shown in FIGS. 18-20. The angle bar 87 is operably connected to the angle bars 43, 44 by movable bars 90, 91, respectively. The upper ends of the bars 90, 91 are pivotally connected as at 92, 93, respectively, to the vertical face 88 of the angle bar 87. The lower ends of the bars 90, 91 are pivotally connected as at 94, 95, respectively, to the angle bars 43, 44. Thus, when the jack 80 is in the retracted position as shown by the full lines in FIGS. 17 and 18, the form unit 1 is in the open position; but when the jack 80 is in the expanded position as shown by the dotted lines in FIG. 17 and by the full lines in FIG. 19, the form unit 1 is in the closed position. Additionally, in FIG. 17 the changed position of each movable part is shown by broken lines and is identified by the same reference character, but with the suffix "C" added thereto. In the preferred embodiment, the jack 80 is removably mounted, and the jack mounting assembly such as the pads 83, 86, and movable bars 90, 91 are mounted only on the form unit 1 which is to serve as the bottom unit in an assembled form 2.
It is to be understood that the jack 80 may be of any conventional telescopic type, and that conventional means such as hydraulic fluid entering at port 98, or a mechanically operated lever (not shown), or any other suitable means may be provided to operate the jack 80.
For purposes of simplicity of illustration, the jack arrangement has been omitted from FIGS. 9-11. Also, the jack 80 can be omitted and the panel 5 moved downwardly to the closed position by manually applying force to the top of the uppermost panel 5B, but a positive pressure means, such as the jack 80, provides the preferred means of lowering the panel 5.
While a lateral locking does occur by the interaction of the cams 8 and the cam followers 9 when the vertical panel 5 is in its lowermost position, an inadvertent jarring action by the crane during the pouring of concrete may cause some movement of the plates 6, 7. Also, it may be necessary or convenient to assemble a form 2 at one location, and then move it to another location where the pouring is to occur. In such a case, the lifting of the form 2 would cause the form 2 to open during transit from the place of assembly to the place of use. Accordingly, a positive but removable locking means is needed to prevent vertical movement of the panel 5 while the form 2 is being transported to the location of use. A positive locking may be secured by attaching bolts 70 to the lowermost form. To accommodate the bolts 70, the plate 5 includes apertures 71 and the sliding plates 6, 7 include threaded apertures 72, as shown in FIGS. 9 and 13. The bolts 70 may be attached prior to erecting the form 2. After the concrete has hardened, it is a simple matter to remove the bolts 70. The openings 71, 72 may be provided for each form unit 1, but need be used only with the one of the units, presumably the lowermost unit 1.
FIGS. 14 and 15 show an alternative embodiment of the invention as applied to a curved form such as a cylindrical form. The elements are similar to those already described and distinguish primarily in that they are curvilinear in plan view. Elements corresponding to elements of the previously described square cross-sectional form 2 are given corresponding reference numerals with suffixes "AA" attached.
A modification of the camming system is shown in FIG. 16. Elements corresponding to elements of the previously described form 2 are given corresponding reference numerals with suffixes "BB" attached. The vertically movable panel 5BB has camming slots 8BB cut therein. Each laterally movable panel 6BB, 7BB includes pairs of projecting pins 9BB which ride in the camming slots 8BB. The solid lines show the pins 9BB in the closed position, with the laterally movable panels 6BB, 7BB in closed and abutting engagement. The phantom lines show the pins 9BB in the open position, with the panels 6BB, 7BB spaced apart. As the panel 5BB is raised vertically, camming slots 8BB also are moved vertically to provide the camming action to move the pins 9BB laterally outwardly, and thus move the panels 6BB, 7BB to their laterally outward position.
A less expensive, but also less desirable modification of the invention would be to have a form with only one expandable corner, with the other corner being hinged. Such a structure, although operable, would not provide the degree of form unit separation of the disclosed embodiments.
Operation
FIG. 2 shows a form 2 consisting of form units 1, 1A, 1B attached to each other as at 69 and ready for pouring of the column. The panels 5, 5A, 5B are in the locked position, and the panels 6, 7 are closed. The form 2 is held in position by guy wires 45. After the concrete is poured, the form 2 will be filled as shown in FIG. 3. After the concrete has hardened, the bolts 70 are removed, the crane hooks 15 are attached to the tongues 14 of the uppermost form unit 1, and the hooks 15 are lifted by the crane to cause the panels 5, 5A, 5B to be displaced upwardly. As shown in FIGS. 9-11, the cams 8 move upwardly to cam the cam followers 9' laterally outwardly, and thus move the panels 6, 7 of the joints 3, 4 outwardly. In turn, the half-sections 21, 22 are separated from the column, as shown in FIG. 4. Further upward movement of the crane hooks 15 cause the entire form 2 to be raised clear of the column. The form 2 is then moved to a new location for pouring of the next column.
When the form 2 arrives at the next location, the crane hooks 15 are removed. Jack 80 (FIGS. 17-19) is inserted between the pads 83, 86 and is activated to cause the panels 5, 5A, 5B to move downwardly, camming the panels 6, 7 laterally inwardly to the closed position. The bolts 70 are then reinserted in the openings 71, 72 in the lowermost form unit 1, and the form 2 is ready for the pouring of the next column. It will be understood that the closing and locking operation could be performed at a convenient location intermediate that of the last column formed and the next column to be formed. The locked form 2 then can be moved, preassembled, to the position where the next column is to formed.
An Alternative Embodiment
Referring to FIGS. 21-26, an alternative embodiment of the invention especially suitable for forming pier shafts for so-called hammerhead caps is shown. Although this embodiment of the invention, like the earlier-described embodiments, can be used with equal facility for the formation of rectangular columns, walls, and the like, the embodiment of the invention illustrated in FIGS. 21-26 is specially preferred for forming shafts or columns that are relatively wide compared to their thickness.
Referring particularly to FIGS. 21 and 22, a form unit 100 consisting of half-sections 102, 104 defines a cavity into which castable material, such as concrete, may be poured to assume the shape of the cavity upon hardening. In accordance with this embodiment of the invention, the half-section 102 includes generally flat walls 106, 108 positioned substantially parallel with each other and connected at their ends by a curved end portion 110. Similarly, the half-section 104 includes wall portions 112, 114 and a curved end portion 116.
The unit 100 includes oppositely disposed expandable and contractible joints 118, 120 which movably connect the half-sections 102, 104 to each other. Each movable joint 118, 120 includes a vertically movable, generally T-shaped member 122. The member 122 carries a plurality of cam means, such as cams 124, 124' which engage a plurality of cam follower means, such as cam followers 126, 126'. The cams 124, 124' and the cam followers 126, 126' interact to move the walls 106, 108, 112, 114 outwardly or inwardly, away from or towards the concrete, so as to expand or contract the joints 118, 120 and thereby open or close the form unit 100.
A plurality of the form units 100 may be stacked and connected to each other to provide a multi-unit form by fastening together upper flanges 128 of a given form unit 100 to lower flanges 130 of a superimposed, comparable form unit 100. Form units 100 in FIG. 23 have been connected in this manner by bolted fasteners 132. Each vertically movable member 122 also includes channel arms 134 adapted to be secured to a tongue 136 included as part of the member 122 on a vertically adjacent form unit 100 by means of a bolted fastener 137. By this construction, members 122 of superimposed form units 100 are interconnected so as to be simultaneously vertically movable. The tongue 136 of the uppermost form unit 100 can be engaged by crane hooks 15 as described previously.
The joints 118, 120 are identical and the structure of only one of them will be described. FIG. 24 illustrates in detail the construction of the joint 118 and its mounting between flanges 140, 142 extending as a continuation of sides 106, 112, respectively. The joint 118 is very simply constructed, and includes as a principal member the vertically movable, generally T-shaped member 122. The T-shaped member 122 includes a flat-sided crossbar 144 for engagement with the concrete. As can be seen in FIG. 24, the crossbar 144 is, in the joint closed position, a continuous extention of the surfaces defined by the walls 106, 112. The crossbar 144 includes tapered outer edge portions 146 and 148. A central portion 150 is positioned perpendicular to the crossbar 144 and forms the body of the T-shaped member 122. The cams 124, 124' are secured to the central portion 150.
A pair of cam follower support plates 152, 154 are secured to the flanges 140, 142, respectively, by means of bolts 156 and nuts 158. The cam followers 126, 126' are secured to the inner faces of the cam follower support plates 152, 154 for engagement with the cams 124, 124'. The edges of the cam follower support plates 152, 154 positioned closest to the crossbar 144 define beveled edges 160, 161, respectively. The tapered edge portions 146, 148 and the beveled edges 160, 161 tightly engage each other when the joint 118 is in the closed position to securely wedge the components together
FIGS. 25 and 26 show the mounting of the cams 124, 124' and the cam followers 126, 126' in more detail. While only two cam pairs 124, 124' and two cam follower pairs 126, 126' are shown, it is to be understood that the form 100 in practice will include additional cams and cam followers that will operate comparably to those shown. It is preferred that the cams 124 and matching cam followers 126 be disposed about every foot in the vertical height of the form unit 100. For clarity of illustration, a portion of the joint 118 has been cut away to better show the interrelationship of the respective cams and cam followers.
The construction of the cams 124 and the cam followers 126 is substantially identical to the cams 8 and the cam followers 9 previously described. The cams 124, 126 include tapered top and bottom surfaces 162, 164, respectively, which engage each other obliquely at the start of the camming action. It is preferred that the top and bottom surfaces 162, 164 define the same angle with respect to the vertical, and that such angle be between 35 and 40 degrees. This will provide a sufficiently rapid outward movement of the cam follower support plates 152, 154 to break the seal between the concrete and the sides 106, 112 of the form 100. The camming action is then completed by contact between outwardly facing camming surfaces 166 of the cams 124 and inwardly facing camming surfaces 168 of the cam followers 126. It is preferred that the camming surfaces 166, 168 define the same angle with respect to the vertical, and that such angle should be between 8 and 10 degrees. This will provide sufficient outward movement of the plates 152, 154 to achieve sufficient clearance between the concrete and the walls 106, 112 to permit the member 122 to be lifted.
The cams 124, 124' include bottom surfaces 170 and the cam followers 126, 126' include top surfaces 172 to facilitate camming contact when the T-shaped member 122 is moved downwardly toward the closed position. It is preferred that the bottom and top surfaces 170, 172 define the same angle with respect to the vertical and that such angle be between 35 and 40 degrees. This will provide sufficient inward force on the plates 152, 154 to initiate the closing process. The camming action then is completed by contact between inwardly facing camming surfaces 174 of the cams 124 and outwardly facing camming surfaces 176 of the cam followers 126 which provide the means to cam the panels 152, 154 and the T-shaped member 122 together as the T-shaped member 122 descends. The surfaces 174, 176 are generally parallel to the previously described camming surfaces 166, 168. All of the cams 124 and the cam followers 126 are secured to their respective mounting surfaces by means of countersunk fasteners 178.
Operation of the Alternative Embodiment
FIGS. 21, 24 and 25 show the form 100 in the closed position with a shaft already having been poured and solidified. In order to remove the form 100 from the shaft, crane hooks 15 are attached to the tongues 136 of the uppermost form unit 100, and the hooks 15 are lifted by a crane to cause the members 122 to be displaced upwardly. As shown in FIG. 26, the cams 126 have moved upwardly to cam the cam followers 126' outwardly, and thus move the plates 152, 154 away from the concrete. The precise camming action between the cams 124 and the cam followers 126 is substantially identical to that of the cams 8 and the cam followers 9 of the previously described embodiment.
As the members 122 are lifted to that position shown in FIG. 26, the crossbars 144 remain in contact with the concrete, but the walls 106, 108, 112, 114 will be separated from the concrete in the region of the joints 118, 120 (FIG. 22). Due to the length of the walls 106, 108, 112, 114 and due to the configuration of the curved ends 110, 116, the half sections 102, 104 will be flexed sufficiently that contact between the concrete and the half-sections 102, 104 will be broken. Further upward movement of the crane hooks 15 will cause the members 122 to be completely disengaged from the half-sections 102, 104. The half-sections 102, 109 then may be removed individually from the pier shaft and moved to the next location.
When the half-sections 102, 104 arrive at the next location they should be placed in their proper relative positions and then re-connected with member 122 being lowered inside the volume defined by the half-sections 102, 104 to a point about one foot above its final, locked position. The member 122 then can be pushed horizontally into the space between the joints 118, 120 and lowered until the cams 124 and the cam followers 126 are engaged in the locking position. The crane hooks 15 then can be removed.
It has been found that the vertically movable members 122 operate sufficiently easy with respect to the other components of the joints 118, 120 that additional forcing means such as the jack 80 are not needed to close the joints 118, 120. When the members 122 are displaced downwardly, the camming action is the reverse of that described previously, and is substantially identical to that cam action already described with respect to cams 8 and cam followers 9. Eventually that position illustrated in FIGS. 24 and 25 will be attained, whereupon the tapered edge portions 146, 148 will engage the beveled edges 160, 161 so as to securely lock the joints 118, 120 together.
It will be appreciated that the operation of the alternative embodiment of the invention is quite similar in many respects to the operation of the previously described embodiment. A distinction with respect to the earlier-described embodiment is that the flanges 140, 142 are moved away from the cap, rather than laterally away from each other. This is because the cams 124 are mounted on the central portion 150 and the cam followers 126 are mounted on the support plates 152, 154, all of which are positioned perpendicular to the outer surface of the cap. Accordingly, upon displacing the cams 124 and the cam followers 126 relative to each other, the flanges 140, 142 will be moved toward or away from the outer surface of the cap. From a practical point of view, an effective separation of the form 100 from a concrete structure is obtained with use of either the first-described embodiment or the alternative embodiment, but the alternative embodiment requires less force to assemble and disassemble.
Although the invention has been described with a certain degree of particularity, it will be appreciated that the present disclosure of the preferred embodiment has been made only by way of example, and that numerous changes in the details of design and construction may be resorted to without departing from the true spirit and scope of the invention. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever degree of patentable novelty exists in the invention disclosed. | A building form into which concrete may be poured to form a column or similar structure includes a plurality of stacked form units having interconnected expandable and contractible joints. The application of a vertically upward force to the joints of the uppermost form unit causes all the units to move together, first laterally outwardly and then upwardly to strip the form from the column. The form thereafter may be moved to another location where the joints of the form units may be contracted to provide a form for pouring another column. The joints include movable portions which are cammed outwardly or inwardly depending on the direction of vertical movement of a central, vertically movable portion. The camming action occurs by the action of cams carried by the vertically movable portion urging cam followers mounted on the movable portions to move side members of the form units away from the column when the form is being stripped from the column, and to urge the side members inwardly when the form is being moved to a position where another column is to be poured. The form according to the invention eliminates the need to remove a plurality of fasteners on each form unit prior to removal of the form from the column, and it also eliminates the need to reinsert a plurality of fasteners in the form units to reassemble the form. The entire form-stripping, form-movement, and form-reassembly technique can be carried out by the application of a vertical force from a mechanism such as a conventional erecting crane. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
(not applicable).
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH OR DEVELOPMENT
(not applicable).
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present patent application refers to a door support bracket provided with adjustment mechanism with three adjustment options: one translating movement and two oscillating movements with respect to two Cartesian axes
2. Description of Related Art
The bracket of the invention has its natural field of application in the sector of modular kitchen furniture, particularly in units internally equipped with extractable drawers, formed by a metal bearing structure on which shelves, baskets, trays or similar items are anchored, according to the type or products to be contained in the drawers.
In this type of furniture the door is usually fixed to the bearing structure of the extractable unit so that the drawer is extracted from its housing when the door is open and automatically reinserted in it when the door is closed.
In view of the above, the door must be fixed to the bearing structure of the extractable drawer with means that allow to adjust the position of the door in order to align it perfectly with the other doors of the kitchen mounted using traditional hinges with ordinary adjustment means.
Doors are currently applied to the bearing structure of extractable drawers with special fixing means with adjustment mechanism, which allows the door to make short oscillating travels with respect to two Cartesian axes in order to align it perfectly with doors above, under and beside it.
However, the double adjustment mode is not sufficient, since it is often necessary to adjust the position of the door with respect to the adjacent doors, and not its vertical position. In other words, the adjustment action should allow for centering the door with respect to adjacent doors, laterally, so that the spaces between two consecutive doors have the same width.
BRIEF SUMMARY OF THE INVENTION
The purpose of the invention is to realize a door support bracket with complete adjustment mechanism, that is with three adjustment options: one translating movement and two oscillating movements with respect to two Cartesian axes.
Thanks to the translating movement the door can be moved rightwards or leftwards without altering its vertical position for perfect centering.
The bracket of the invention comprises a rectangular metal plate of box-type shape, whose ends house two runners that can translate for a short distance by means of an adjustment screw located on the two opposite sides of the box-type bracket that engage in a threaded hole located on the side of the runners.
The runners are fixed directly to the internal side of the door with a special combination of screws, which allows for moving the door forward or backwards, in parallel position.
BRIEF DESCRIPTION OF THE DRAWINGS
For major clarity the description of the bracket of the invention continues with reference to the enclosed drawings, which are intended for purposes of illustration and not in a limiting sense, whereby:
FIG. 1 is a schematic perspective view of a cabinet that housing an extractable drawer, whose bearing structure has been fixed to a pair of brackets according to the invention to support the door that closes the housing of the extractable drawer.
FIG. 2 is an exploded axonometric view of all components of the bracket of the invention.
FIG. 3 is an axonometric view of the bracket of the invention with two runners mounted on its internal side.
FIG. 4 shows the bracket of the invention applied on the internal side of a door and sectioned with a vertical plane that passes through the axis of screw used to fix each runner to the door.
FIGS. 5A to 5 C show the adjustment action that is carried out to make the door oscillate with respect to an horizontal axis.
FIGS. 6A to 6 C show the adjustment action that is carried out to make the door oscillate with respect to a vertical axis.
FIGS. 7A to 7 D show the adjustment action that is carried out to make the door translate rightwards or leftwards.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 2 and 3, the bracket ( 1 ) of the invention consists of a rectangular metal plate of box-type shape, whose ends house two runners ( 2 ) that can translate for a short distance by means of an adjustment screw ( 3 ) located on the two opposite sides ( 1 a ) of the box-type bracket ( 1 ) that engage in a threaded hole ( 2 a ) located on the side of the runners ( 2 ).
As it is shown in FIG. 4, the runners are fixed directly to the internal side of the door (S) with a special combination of screws, which allows for moving the door (S) forward or backwards, in parallel position.
More precisely, each runner ( 2 ) has a large threaded hole ( 2 b ) in central position, into which a special threaded dowel ( 4 ) is screwed. The dowel ( 4 ) has a blind axial hole ( 4 a ), whose bottom wall ( 4 b ) has a hole for an ordinary fixing screw (S) used to hold the dowel ( 4 ) and the runner ( 2 ) against the internal side of the door (S).
As it is shown in the drawings identified with (A) in FIGS. 5C and 6C, after loosening the screw ( 5 ), the dowel ( 4 ) can be screwed inside the support runner (as shown in the figures identified with (B) in FIGS. 5C and 6C) in order to move the door (S) closer or farther from the runner ( 2 ).
As it is shown in the drawings identified with (C) in FIGS. 5C and 6C, after placing the door (S) at the correct distance from the runner ( 2 ), it will be necessary to tighten the screw ( 5 ) again on the dowel ( 4 ) so that the dowel ( 4 ) can no longer turn inside the hole ( 2 b ).
Since the door (S) is supported by an overlapped pair of brackets ( 1 ) according to the invention, as shown in FIG. 1, it appears evident that the oscillation of the door with respect to an horizontal axis can be obtained by using the dowels ( 4 ) of the upper and lower brackets, as shown in FIG. 5 B.
Vice versa, as it is shown in FIG. 6B, the oscillation of the door with respect to a vertical axis can be obtained by using the two dowels ( 4 ) of the same bracket ( 1 ), as shown in FIG. 7 B.
Finally, the lateral movement of the door without altering its vertical position can be obtained by using the screws ( 3 ), after loosening the screws ( 6 ) that fix the runners ( 2 ) to the bracket ( 1 ).
To this end it must be said that the ends of the bracket ( 1 ) housing the runners ( 2 ) feature a series of three slots aligned in the same vertical line with respect to one another, with a larger central slot ( 1 b ) between two smaller slots ( 1 c ).
The central slot ( 1 a ) houses the dowel ( 4 ) that slides freely in it, while the smaller slots ( 1 c ) house the screws ( 6 ) that slide freely in them.
Each runner ( 2 ) has two small threaded holes ( 2 c ) above and below the hole ( 2 b ), in which the screws ( 6 ) are inserted through the slots ( 1 c ) of the bracket ( 1 ) and tightened. | The present invention refers to a door support bracket provided with adjustment mechanism with three adjustment options: one translating movement and two oscillating movements with respect to two Cartesian axes. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a photoelectric converting apparatus of the type having a plurality of photosensors and a plurality of signal output lines for picking up signals from the photosensors, wherein the signals are picked up through signal output terminals smaller in number than that of the signal output lines.
2. Related Background Art
In order to read signals from the entirety or part of a color sensor made of a plurality of photosensors disposed one or two-dimensionally, it becomes necessary to provide a plurality of signal output lines.
FIG. 1 is a circuit diagram showing one example of a conventional photoelectric converting apparatus.
In the Figure, there are provided sensor line blocks 101 and 102 each constructed of one-dimensionally disposed photosensors Signals from each sensor line block are sequentially read via signal output lines 103 and 104 which are commonly connected to an amplifier 105 having a signal output terminal 106. During the reading of signals from one sensor line block, reading of signals from the other line sensor block is inhibited. Thus, signals from the two signal output lines can be read via the single output terminal, resulting in fewer numbers of wires for connection to external circuitry.
In operation of the above conventional photoelectric converting apparatus, signal from the sensor line blocks 101 and 102 are temporarily stored in charge storage capacitors or wiring capacitance C1 to Cn. Signals from the sensor line blocks 101 and 102 are sequentially picked up and transferred to the signal output lines 103 and 104, respectively under the control of shift registers. The signals are then outputted via the amplifier 105 at its signal output terminal 106
However, since the signal output lines 103 and 104 are connected together at the input terminal Of the amplifier, each of the wiring capacitances Cw1 and Cw2 of the signal output line are added together, resulting in a large capacitance on each signal output line. Thus, there arises a problem that the output of a signal stored, for example, in the charge storage capacitor C1 is reduced at the signal output line 103 by the large capacitance.
The above problem becomes more serious in the case of a large number of sensor lines and hence a large number of signal output lines.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an image pickup device and apparatus eliminating the above-described prior art problem.
It is another object of the present invention to provide an image pickup device having a high degree of freedom in circuit design.
It is a further object of th present invention to provide a photoelectric converter with less reduction in signal output level.
It is another object of the present invention to provide an image pickup apparatus suitable for high resolution.
The above objects can be achieved in accordance with the embodiments of the present invention. In a photoelectric converting apparatus of the type having a plurality of photosensors and a plurality of signal output lines for picking up signals from the photosensors, wherein the signals are picked up through signal output terminals smaller in number than that of the signal output lines, the photoelectric converter is characterized, according to one aspect of the present invention, by apparatus wherein the signal output lines each have switch means for switching the signal output line and connecting a desired output line to a signal output terminal.
Since a plurality of selection means (scanning circuits such as shift registers) are provided, the drive frequency of selection means may use a lower frequency in the case where a high frequency operation becomes necessary for a great number of photosensors, thus enabling a high degree of freedom in circuit design, pattern design for semiconductor devices and the like.
Since each signal output line is connected to the signal output terminal via switch means, the wiring capacity of the signal output line from which a signal is picked up via the closed switch means can be greatly reduced by opening the other switch means. Therefore, reduction in signal level at the signal output line can be avoided, and an image pickup apparatus with a high resolution and high output can be easily realized.
Other objects and advantages of the present invention will become apparent from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram showing an example of a conventional photoelectric converting apparatus;
FIG. 2A is a schematic circuit diagram showing an embodiment of the photoelectric converting apparatus according to the present invention;
FIG. 2B is a schematic cross section of a photoelectric conversion cell disclosed in Japanese Patent Laid-open Gazette Nos. 12579/1985 and 12765/1985;
FIG. 2C is a equivalent circuit of the photoelectric conversion cell shown in FIG. 2B;
FIG. 3A is a circuit diagram showing an example of a driver for a sensor line block using the photoelectric conversion cells of FIG. 2B;
FIG. 3B is a timing chart for explaining the operation of the circuit shown in FIG. 3A;
FIG. 4 is a block diagram showing an example of an image pickup apparatus using the embodiment of FIG. 3A;
FIG. 5 is a schematic circuit diagram showing an embodiment of the photoelectric converting apparatus according to the present invention;
FIG. 6 is a timing chart for explaining the operation of the scanning circuit; and
FIGS. 7, 8, 9 and 10 are timing charts showing first to fourth examples of timings of pulses outputted from the driver 117.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 2A is a schematic circuit diagram showing an embodiment of the photoelectric converting apparatus according to the present invention.
In the Figure, a signal output line 103 from which signals from a sensor line block 101 are sequentially outputted is connected to the input terminal of an amplifier 105 via switch means 107. Similarly, a signal output line 104 from which signals from a sensor line block 102 are sequentially outputted is connected to the input terminal of the amplifier 105 via switch means 108.
MOS transistors are used as switch means in this embodiment. However, other devices having a low conductive resistance such as analog switches may obviously be used.
Also, instead of two signal output lines, a larger number of signal output lines may be commonly connected to the input terminal of the amplifier 105 via switch means.
In operation of this embodiment, while signals from the sensor line block 101 are sequentially outputted to the signal output line 103 by means of a shift register 115, switch means 107 is kept turned on and switch means 108 is kept turned off. Therefore, the wiring capacitance of the signal output line 104 becomes substantially the wiring capacitance Cw1 of the signal output line 103 itself. Thus, if each capacitance C of charge storage capacitors C1 to Cn is set sufficiently large as compared with Cw1, then it becomes possible to read signals from sensors without reducing their signal level.
Conversely, while signals from the sensor line block 102 are read by means of a shift register 116, switch means 107 is kept turned off whereas switch means 108 is kept turned on. Similarly in this case, signals can be read without reducing their signal level.
Next, the structure and operation of the line sensor block in this embodiment will be described in more detail.
FIG. 2B is a schematic cross section of a photoelectric conversion cell disclosed in Japanese Patent Laid-open Gazettes Nos. 12759/1985 through 12765/1985, (corresponding to U.S. Pat. No. 4,686,554) and FIG. 2C is an equivalent circuit of the photoelectric conversion cell.
In the Figures, each photosensor cell is formed on an n+silicon substrate 1 and electrically isolated from adjacent photosensor cells by an element isolation region 2 made of, for example, SiO 2 , Si 3 N 4 , polysilicon or the like.
Each photosensor cell has the following constituent elements: A p-region 4 is formed by doping p-type impurity on an n - -region 3 of low impurity concentration formed by the epitaxy method or the like. An n + -region 5 is formed in the p-region 104 by the impurity diffusion method, the ion implantation method or the like. The p-region 4 and n + -region 5 serve as the base and emitter of a bipolar transistor, respectively.
Formed on an oxide film 6 deposited on the n - -region 3 with the above regions is a capacitor electrode 7 of predetermined area which faces the p-region 4 with the oxide film 6 interposed therebetween. The potential of the p-region 104 in a floating state is controlled by a pulse voltage applied to the capacitor electrode 7.
The photosensor cell is constructed further of an emitter electrode 8 connected to the n + -region 5, an n + -region 11 of high impurity concentration formed on the substrate 1, and an electrode 12 supplying a potential to the collector of the bipolar transistor.
Next, the fundamental operations of the photosensor constructed as above will be described. First, assuming that the p-base region 4 of the transistor is at a negative potential and at a floating state. Upon incidence of light 13 to the p-region 4, holes of light-induced electron/hole pairs are accumulated in the p-region 4 the potential of which rises positively due to the accumulated holes (accumulation operation).
Next, a readout positive pulse is applied to the capacitor electrode 7 so that a readout signal corresponding to a change in base potential during the accumulation operation is outputted from the emitter electrode (readout operation). Repetitive readout operations are possible because the accumulated charge amount in the base p-region 4 does not decrease to a large extent.
To remove accumulated holes in the p-region 4, the emitter electrode 8 is grounded and the capacitor electrode 8 is applied with a positive refresh pulse. With this pulse applied, the p-region 4 is forward biased relative to the n + -region 5 so that accumulated holes are removed. At the trailing edge of the refresh pulse, the p-region 4 takes again its initial negative potential (refresh operation). Thereafter, similar accumulation, readout and refresh operations are repeated.
Briefly stating the above proposed method, light-induced carriers are accumulated in the base p-region 4 to control a current passing through the emitter and collector electrodes 8 and 12 in accordance with the accumulated charge quantity. The accumulated carriers are read after amplifying them by the amplification function of each cell, thereby achieving a high output and sensitivity, and less noise.
The potential V p of the base with light-induced carriers (holes in this case) accumulated therein is given by Q/C, wherein Q represents the charge of carriers accumulated in the base region, and C represents a capacitor coupled to the base region. As apparent from the above equation, the values of Q and C both become small as the cell size becomes small due to high integration. Thus, the light-induced potential V p is maintained substantially constant Therefore, the above proposed method may become useful in the future for a means of obtaining a high resolution.
FIG. 3A is a circuit diagram showing an example of a driver for the sensor line block using the above photoelectric conversion cells, and FIG. 3B is a timing chart for explaining the operation of the driver circuit.
Referring to FIG. 3A, each collector electrode 12 of the photoelectric conversion cells S1 to Sn is supplied with a predetermined voltage. Capacitor electrodes 7 are connected in common to a terminal 110 to which a signal φ 1 for the readout and refresh operation is applied. Each emitter electrode 8 is connected to respective vertical lines L1 to Ln which are connected to one main electrodes of respective buffer transistors Ta1 to Tan.
The gate electrodes of the buffer transistors Ta1 to Tan are connected in common to a terminal 111 to which a signal φ 2 is applied. The other main electrodes of the buffer transistors Ta1 to Tan are grounded via charge storage capacitors C1 to Cn serving as accumulation means, and also connected to the signal line 103 via transistors T1 to Tn. The gate electrodes of the transistors T1 to Tn are respectively connected to the parallel output terminals of the shift register from which signals φh1 to φhn are sequentially outputted.
The signal output line 103 is grounded via transistor Tr for refreshing the signal output line 103. The gate electrode of the transistor Tr is supplied with a signal φ r2 .
The vertical lines L1 to Ln are grounded via respective buffer transistors Tb1 to Tbn. The gate electrodes of the buffer transistors Tb1 to Tbn are connected in common to a terminal 112 to which a signal φ 3 is applied.
Next, the operation of the embodiment constructed as above will be described with reference to the timing chart shown in FIG. 3B.
Refresh Operation First, signals φ 2 and φ 3 are made high level to cause the buffer transistors Ta1 to Tan to turn on. Therefore, the emitter electrodes 8 of the photoelectric conversion cells S1 to Sn are grounded and residual charges in the charge storage capacitors C1 to Cn are removed therefrom. When signal φ 1 becomes high level to apply a positive refresh voltage to the capacitor electrode 7 of each photoelectric conversion cell, a refresh operation is performed as described before. When signal φ 1 becomes low level, the base region 4 of each cell returns to its initial negative potential.
Accumulation Operation
Signals φ 2 and φ 3 are made low level to cause the buffer transistors Ta1 to Tan and Tb1 to Tbn to turn off. In this condition, holes of light-induced electron/hole pairs are accumulated in the base region 4 of each photoelectric conversion cell S1 to Sn so that the base potential of each cell rises to a higher value from the initial negative potential by the accumulated potential corresponding to the incident light amount.
Readout Operation
When signals φ 1 and φ 2 are made high level, signals read from the emitter electrodes 8 of the photoelectric conversion cells S1 to Sn are accumulated at the same time in the charge storage capacitors C1 to Cn via the buffer transistors Ta1 to Tan.
Succeedingly, after signals φ 1 and φ 2 are made low level, a readout operation for each signal from the signal output line 103 starts.
First, when high level signal φh1 is outputted from the shift register, the transistor T1 is caused to turn on. Then, a signal of the photoelectric conversion cell S1 stored in the charge storage capacitor C1 appears on the signal output line 103, and read out from the signal output terminal 106 via switch means 107 and the amplifier 105 as described previously.
Succeedingly, signal φ r2 is made high level to cause the transistor Tr to turn on. Thus, residual charge on the signal output line 103 is removed via the transistor Tr to effect a refresh operation.
Thereafter, high level signals φh2 to φhn are sequentially outputted in a similar manner as above to cause the transistors to sequentially turn on. Thus, signals stored in the charge storage capacitors C2 to Cn are sequentially outputted on the signal output line 103. Each time after a signal has been outputted to the external circuit, signal φ r2 is made high level to refresh the signal output line 103.
After all the signals stored in the charge storage capacitors C1 to Cn have been read out to the external circuit, the above-described refresh operation is carried out, and the similar accumulation and readout operations follow.
While the sensor line block 101 is read, switch means 107 is turned on and switch means 108 is turned off. Conversely, while the sensor line block 102 is read, switch means 107 is turned off and switch means 108 is turned on.
The type of photosensor is not limited to the above embodiment but photosensors such as photoconductive type sensors, photodiodes, static induction transistors, etc. may be used.
FIG. 4 is a block diagram showing an example of an image pickup apparatus using the above embodiment. In this case, it is needless to say that a number of sensor line blocks are provided and switch means is provided for each sensor line block.
In the Figure, an image pickup device 301 has a similar construction to the above embodiment. The output signal Vo therefrom is processed including a gain adjustment by a signal processing circuit 302 to output it as a standard television signal in the form of NTSC signal or the like.
Various types of pulses for driving the image pick-up device 301 are supplied from a driver 303 which is controlled by a control unit 304. The control unit 304 adjusts a gain and the like of the signal processing circuit 302 in accordance with an output from the image pickup device, and adjusts the incident light amount to the image pickup device 301 by controlling an exposure control unit 305.
As described in detail, each signal output line of the photoelectric converter of the above embodiment according to the present invention is coupled to the output terminal via switch means. Therefore, a wiring capacitance on a signal output line from which a signal is outputted via closed switch means is greatly reduced as compared with a conventional one, by opening switch means on the other signal output lines. Hence, it is possible to prevent lowering the level of a signal outputted from the signal output line.
Next, a second embodiment of the present invention will be described in detail with reference to the associated drawings.
FIG. 5 is a schematic circuit diagram showing an embodiment of the photoelectric converter according to the present invention.
In this embodiment, there are provided sensor line blocks 101 and 102 each having a plurality of n photosensors. Each sensor line block is intended herein to include the concept wherein it represents odd/even lines of a sensor group such as an area sensor, or it represents odd/even photosensors on an arbitrary line, and the like. In this embodiment, for the purpose of convenience of description, two sensor blocks are shown.
In the Figure, n output terminals of the sensor line block 101 are connected to capacitors C11 to C1n and connected in common to a signal output line 103 via transistors T11 to T1n. Each gate electrode of transistor T11 to T1n is inputted with pulses φ 11 to φ 1n from a scanning circuit 115. Pulses φ 31 and φ 32 are inputted to input terminal a and b of the scanning circuit 115.
The signal line 103 is grounded via transistor Tr1 and connected to the input terminal of an amplifier 105 via a transistor 107 serving as switch means. A pulse φ c1 is inputted to the gate electrode of the transistor Tr1, and a pulse φ sr1 is input to the gate electrode of the transistor 107.
The sensor line block 102 is constructed in a similar manner. N output terminals of the sensor line block 102 are connected to capacitors C21 to C2n and connected in common to a signal output line 104 via transistors T21 to T1n. Each gate electrode of transistor T21 to T2n is inputted with pulse φ 21 to φ 2n from a scanning circuit 116. Pulses φ 32 and φ 31 are inputted to input terminal a and b of the scanning circuit 116, as opposed to the case of the scanning circuit 115.
The signal line 104 is grounded via transistor Tr2 and connected to the input terminal of the amplifier 105 via a transistor 108 serving as switch means. A pulse φ c2 is inputted to the gate electrode of the transistor Tr2, and a pulse φ sr2 is inputted to the gate electrode of the transistor 108.
The operation of the scanning circuits 115 and 116 of this embodiment is as follows.
FIG. 6 is a timing chart illustrating the operation of the scanning circuit.
The scanning circuits 115 and 116 are two-phase driven by pulses φ 31 and φ 32 . With the interconnection shown in FIG. 5, pulses φ 11 to φ 1n are outputted from the scanning circuit 115 in synchronization with the pulse φ 31 , whereas pulses φ 21 to φ 2n are outputted from the scanning circuit 116 in synchronization with the pulse φ 32 , respectively as shown in the timing chart. Therefore, based on the timings of pulses φ 31 and φ 32 , the scanning circuits 115 and 116 can independently or alternately be operated at desired timings.
The above-described various pulses are supplied from a driver 117 which outputs a pulse at the timing in synchronization with a clock signal from an oscillator 118.
Transistors 107 and 108 are used as switch means in this embodiment. However, obviously other devices having a low conductive resistance such as analog switches may be used similar to the embodiment shown in FIG. 2.
It is to be understood that the invention includes the arrangement wherein three or more sensor line blocks are provided and the signal output lines are connected in common to the input terminal of the amplifier 109 via respective switch means.
Next, the operation of this embodiment will be described with reference to FIG. 7 which shows a timing chart illustrating a first example of timings of pulses outputted from the driver 117.
In the Figure, first, pulse φ sr1 is made high level and pulse φ sr2 is made low level to turn on the transistor 107 and turn off the transistor 108.
In this condition, pulse φ 11 is outputted from the scanning circuit 115 to turn on the transistor T11. Thus, a signal at the first cell of the sensor line block 101 is picked up from the capacitor C11 onto the signal output line 103, and hence to the external circuit via the transistor 107, the amplifier 105 and the output terminal 106.
Simultaneously with the pulse φ 11 , pulse φ c2 is made high level to turn on the transistor Tr2 so that residual charge on the signal output line 104 is removed.
After the signal at the first cell of the sensor block 101 has been outputted, then pulses φ sr1 and φ sr2 are inverted respectively to low level and high level to turn off the transistor 107 and turn on the transistor 108.
In this condition, pulse φ 21 is outputted from the scanning circuit 116 to turn on the transistor T21. Then a signal at the first cell of the sensor line block 102 is picked up from the capacitor C21 onto the signal output line 104, and hence to the external circuit via the transistor 108 and the amplifier 105.
Simultaneously with pulse φ 21 , pulse φ c1 is made high level to turn on the transistor Tr1 and remove residual charge present at the preceding signal on the signal output line 103.
Thereafter, in a similar manner as above, signals from the sensors in the sensor line blocks 101 and 102 are alternately and sequentially outputted to the external circuit in response to pulses φ 11 to φ 1n from the scanning circuit 115 and pulses φ 22 to φ 2n from the scanning circuit 116.
It is to be noted that the wiring capacitance on a signal output line from which a signal is read is substantially the wiring capacitance Cw of the line itself because one of the transistors 107 and 108 from which a signal is not read is turned off. Thus, by setting each capacitance C of the capacitors C11 to C1n and C21 to C2n sufficiently larger than Cw, it becomes possible to read a signal from a cell without greatly reducing its signal level.
Further, since each sensor line block 101 and 102 is provided with respective scanning circuit 115 and 116, the scanning circuit can be driven at a lower operating frequency corresponding to n photosensors although 2n photosensors are used, thus leading to a high degree of freedom in design.
By changing the timings of pulses φ 31 and φ 32 applied to the scanning circuits, the following drive methods can be used.
FIG. 8 is a timing chart showing a second example of timings of pulses outputted from the driver 117.
In the second example, photosensors in the sensor line blocks 101 and 102 are sequentially read one block at a time. Namely, the transistor 107 is turned on and the transistor 108 is turned off by applying pulses φsr1 and φ sr2 . In this condition, pulses φ 11 to φ 1n are sequentially outputted from the scanning circuit 115 to read all the signals from the cells in the sensor line block 101. Similarly, the transistor 107 is turned off and the transistor 108 is turned on to read all the signals from the sensor line block 102.
FIGS. 9 and 10 are timing charts showing the third and fourth examples of timings of pulses outputted from the driver 117.
As seen from the timing charts, signals can be read from only one of the sensor line blocks by keeping the other scanning circuit turned off.
As appreciated from the foregoing detailed description of the photoelectric converting apparatus according to the present invention, a plural number of selection means for selecting photosensors in sensor line blocks are provided. Therefore, even if a high frequency operation is required for a large number of photosensors, selection means can be operated at a lower frequency, resulting in a high degree of freedom in circuit design, pattern design for semiconductor devices, and the like.
Further, each signal output line is connected to the signal output terminal via switch means. During the picking up of a signal from a signal output line, switch means for this line are closed whereas switch means for the other lines are opened. Therefore, it is possible to prevent lowering the level of a signal picked up from the signal output line, and to readily realize a high resolution and high output image pickup apparatus. | A photoelectric converting device having a plurality of line sensors, each line sensor having an output line and scanning means for scanning that line sensor. Selection circuit selectably directs a signal from one of the plural output lines to a common output terminal. A reset device resets the common output line to a predetermined level in response to the scanning of the line after the signal has been directed to the common output terminal. The readout may be conducted by scanning the plurality of line sensors by alternatively scanning photoelectric conversion cells from different line sensors. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a screen for treating fibrous suspensions, such as pulps, of the wood processing industry. Especially it relates to the construction of a rotor element for the screen.
[0002] Pressure screens are essential devices in the production of pulp and paper. They remove from the pulp suspension mainly impurities, over-sized pieces of wood and fiber bundles as well as other undesired substances. The screen can also fractionate fibers according to their length for improving the properties of the pulp. The precise function of the screen is dependent on the location in the process where it is used. In the screening process the water suspension of the pulp fibers is typically pumped into a cylindrical chamber, wherein the suspension is brought to contact with the screen surface and a rotor moving at high velocity. The rotational velocity of the rotor pushes the fibrous material into movement, whereby part of it is passed as accept through apertures in the screen surface. The high-speed rotor applies positive and negative impact pulses to the suspension. The positive impact pulses push the fibers through the apertures in the screen and may fractionate the fibers. The negative impact pulses provide for a regular flush-back of the apertures in the screen surface so that the fibers do not plug the apertures.
[0003] The pulp suspension consists of millions of elastic fibers that easily attach to each other forming so-called fiber flocks. Even at a low consistency such as 0.01% the fibers form unstable flocs. In a typical screening consistency, 1-3% the fibers form stable flocks and fiber networks hamper the screening. The fibers and undesired solid matter are periodically removed from the net in order to enable the screening the remaining fibers from the flocks and fiber networks into reject and accept fibers. When the pulp consistency increases, the force required for decomposing the fiber network increases intensively and finally a process limit is reached, where the apertures in the screen surface or the reject line is clogged. A large number of various rotor solutions has been developed with the aim of ensuring a continuous screening operation.
[0004] In principle, the rotors can be divided into two basic groups, open and closed rotors. Both are being used and their purpose is, as known, to keep the screening surface clean, i.e. to prevent the formation of a fiber mat on the screening surface. The first group is characterized in that the interior of the screen drum is provided with a rotary shaft or a rotor, whereto blades are attached by means of arms. An example of this kind is the rotor solution according to U.S. Pat. No. 4,193,865, where the rotor is arranged rotatably inside a cylindrical stationary screen drum, said rotor comprising blades located in the vicinity of the screen drum surface, which blades in the construction according to said patent form an angle with the drum axis i.e. the blades extend obliquely from one end of the screen drum to another. When moving, the blades impact pressure pulses on the screen surface, which pulses open the surface apertures. There are also solutions, in which the blades have been located on both sides of the screen drum. In that case, the suspension to be treated is fed to the inside or to the outside of the drum and the accept is, respectively, discharged from the outside or inside of the drum.
[0005] In stationary rotors the rotor is an essentially closed cylindrical piece, the surface of which is provided with pulsation members, for instance almost hemispherical protrusions, so-called bulges. In this kind of an apparatus the pulp is fed into a treatment space located between the rotor cylinder and the screen drum outside thereof, whereby the purpose of the rotor protrusions, e.g., the bulges, is both to press the pulp against the screen drum and by means of its trailing edge to withdraw the fiber mat off the screen drum apertures. The bulges can be replaced by other kinds of protrusions.
[0006] A solution widely used in the market is a represented by a method according to FI patent 77279 (U.S. Pat. No. 5,000,842) and the solution developed for the implementation thereof. The method according to said patent is characterized in that the fiber suspension is subjected to axial forces with varying intensity and effective direction, the direction and intensity of which are determined based on the mutual axial positioning of the point of application and the countersurface of the screen drum and by means of which the axial velocity profile of the fiber suspension is changed while maintaining the flow direction continuously towards the discharge end. Preferably the surface of the rotor is divided into four zones: feed, feed and mixing, mixing, and efficient mixing. The rotor surface is typically provided with 10-40 protrusions, the shape of which varies according to the zone i.e. the axial part of the rotor that they are located on. The protrusions on the housing surface of the rotor are mainly formed of front surfaces facing the flow, preferably surfaces parallel to the housing surface and back surfaces that descend towards the housing surface of the rotor. The housing surface of the rotor is provided with protrusions of several different forms, which have been arranged onto the rotor housing so that two or more circumferential zones are formed separated from each other in the axial direction of the rotor, such as e.g. 4 zones. At least part of the front surfaces of the protrusions forms an angle with the axial direction. The front surface of the protrusions can be divided into two parts that form with the axial direction angles of different size. The variation interval of the angles is −45°-+45° compared to the axial direction. However, the functioning principle of the protrusions is the same as in other corresponding devices. The abrupt front surface imparts a strong pressure shock to the fiber mat on the screen drum, whereby the accept is pressed through the apertures of the drum. The sloping back surface of the protrusion withdraws some water back to the screening zone and thus releases from the grooves and apertures major particles and fiber flocks thus cleaning the screen drum.
[0007] U.S. Pat. No. 5,192,438 describes a rotor which provides high intensity axial shear stress in addition to high positive pulses and negative pulses. The rotor has a contoured surface including a plurality of protrusions. A protrusion has a front plane, an upper plane, an inclined plane and edge surfaces, which may converge. The trailing surface of the protrusion is abrupt.
[0008] So, in prior known solutions the functional prerequisite of pressure screens starts from the presumption that the rotor element is to develop an adequate pressure impulse on the interface to make the fiber particles flow through the screening surface and that the rotor element is to create by its trailing edge a negative pressure impulse to generate a turbulence that cleans the apertures clogged by the previous positive impulse. It has also been generally presented in the field that a negative impulse withdraws liquid back towards the feeding space preventing excess thickening of the fiber suspension in the feeding space and in its part cleaning the apertures of the screening surface. For enabling to create these conditions, the rotor must have an adequate rotational speed, which is, however, limited by energy consumption and mechanical durability of the screen, a typical speed for a rotor described in FI-patent 77279 (U.S. Pat. No. 5,000,842) is 24 m/s.
[0009] In the present industrially used pressure screen applications the rotor solutions have enabled to reach the maximum feed consistency level of pulp. The consistency level is almost the same for different rotor types, for instance for softwood (SW)-pulp approximately 2-3%. Thus, there is a need in the field to develop a screen rotor that will allow higher feed consistencies.
SUMMARY OF THE INVENTION
[0010] A screen, especially a pressure screen, has been developed having a rotor element construction such that thicker pulp than before can be treated and thus essentially increase the feed consistency of the pulp compared to known solutions.
[0011] The screen apparatus, in one embodiment, comprises a housing, conduits therein at least for the fiber suspension being fed in, for reject and accept, as well as a rotor and a cylindrical screen drum installed in the housing, at least one of which is rotatable, whereby the rotor surface is provided with rotor elements that are in proximity to the screen drum surface, whereby a rotor element mainly comprises a front surface facing the flow, an upper surface and a descending trailing surface. The trailing surface of the rotor element may be curved and the sidewalls thereof converge at least along a part of their length towards the back point of the element. The length of the element, i.e. the distance between the front surface and the back point, is essentially greater than the greatest width of the element, i.e., the distance between the sidewalls.
[0012] The sidewalls of the trailing surface converge towards the back point such that the opposite sidewalls converge at the back point or substantially converge such that the back point is a narrow back section that may be curved.
[0013] According to one embodiment in a screening device, a rotor element is on a rotor coaxial with a cylindrical screen drum, wherein a gap between the rotor and screen drum receives a pulp flow and at least one of the rotor and screen drum rotates relative to the other, wherein the rotor element protrudes radially outward from a surface of the rotor and towards the screen drum, the rotor element comprising:
an upper surface and a front face between the surface of the rotor and the upper surface, wherein the front face faces a circumferential movement of the pulp-flow in the gap; a trailing surface extending downstream of the pulp flow from the upper surface and the trailing surface tapers to the surface of the rotor and meets the surface at a back point of the trailing surface, and opposite sidewalls of the trailing surface gradually converging at the back point.
[0017] The trailing surface of the rotor element allows the pulp to flow without stalling, as smoothly as possible and without causing a strong turbulence on the screening surface. In the rotor elements disclosed herein, a positive pulse is first created, but after that by the design of the trailing surface of the rotor element a situation is generated where the trailing surface releases the pulp fibers as calmly as possible, minimizing turbulence on the screening surface. In the rotational direction of the rotor, the pulp first contacts the front surface of the rotor element, which guides the pulp to a capacity zone where the flow-through of the pulp is generated. The capacity zone is formed by a zone in the vicinity of the surface of the screen basket, where fibers enter the accept side. The front surface can be planar. It can be perpendicular or inclined in relation to the rotor surface. The front surface can be formed of two pieces positioned symmetrically or asymmetrically in relation to the longitudinal center axis of the element forming a wedge to receive the flow. The front surface of the rotor element can also be curved. The front end, i.e. the front surface of the rotor element, the upper surface or plane parallel to the rotor surface and optionally a shoulder are designed so that the pulp is led as an essentially smooth film into the space between the screening surface and the rotor element, wherefrom the accepted pulp fibers are run and pressed through the screening surface into the accept side. According to an embodiment, the rotor element can also be devoid of a shoulder, such that the pulp may as well contact directly a front surface and a trailing surface that curves therefrom towards the back point. A rotor element's planar upper surface devoid of a shoulder can have an advantageous influence on energy consumption.
[0018] The trailing surface of the rotor element is curved and the sidewalls thereof converge at least along a part of their length towards and at the back point of the element. According to an embodiment, the trailing surface has at least a first part and a second part, whereby the first part is closest to the front surface or the possible shoulder and its sidewalls are substantially parallel to each other, i.e. the width does not change, while the sidewalls of the second part converge towards and to the back point. According to another embodiment, the sidewalls of the trailing surface converge towards and to the back point essentially starting from the shoulder.
[0019] In the initial point of the curved trailing surface of the rotor element a lag angle is preferably less than 10°, whereby the angle is formed between a tangential plane intersecting said initial point of the of the trailing surface curve and a tangential plane of a curvature radius of the trailing surface curve.
[0020] According to an embodiment the front part and/or back part of a novel rotor element can also be hydrofoil-like. One end of the rotor element is a stationary piece, whereby the element can e.g. be constructed as a stationary piece, but the front portion's part facing the rotor body has been cut away. That way, the front part's surface receiving the pulp flow is hydrofoil-like and guides the pulp smoothly. Preferably, the front edge of the hydrofoil-like front portion is curved.
[0021] The rotor elements disclosed herein allow the fiber suspension to be led as a film-like flow into the narrow space between the element and the screening surface, in which space the fiber suspension is pressed through the apertures in the screen surface. The gently curved trailing surface the sidewalls of which converge towards the back point guides the flow towards the back point and minimizes stalling of the flow, increase of flow resistance caused by cavitation, and decreases turbulence that prevents water from being removed to the accept side and the reject from thickening. Thus, the escape of small impurities and first of all water into accept is prevented, as the retention capacity of the fiber net is improved due to calm flow conditions. Thus, the thickening of the reject is decreased compared to known screens.
[0022] The design of rotor element disclosed herein is hydro-dynamically efficient, and it allows a greater rotational speed without remarkable increase in energy. Simultaneously, the mechanical stress of the device is decreased. The rotor having the elements according to the invention operates at low circumferential speeds as well, which results in remarkable saving in energy.
[0023] The rotor elements disclosed herein may be applied in connection with a closed rotor, most usually having a cylindrical shape, but it can also be e.g. conical. The rotor can also be open, whereby the rotor elements are supported by arms or other supporting members.
SUMMARY OF DRAWINGS
[0024] The present invention is described in more detail with reference to the appended figures, in which
[0025] FIGS. 1 a , 1 b , 1 c and 1 d illustrate schematically the flow conditions surrounding a known rotor element ( FIGS. 1 a and 1 b ) and an embodiment of novel rotor element according ( FIGS. 1 c and 1 d );
[0026] FIGS. 2 a to 2 d illustrate preferred embodiments of the rotor element;
[0027] FIG. 3 illustrates a schematic cross section of a screen;
[0028] FIGS. 4 a and 4 b illustrate a top view of a plurality of rotor elements arranged on a surface of the rotor, where the rotor is shown in planar form for illustrative purposes,
[0029] FIGS. 5 a to 5 f illustrate preferred embodiments of the novel rotor element, and
[0030] FIG. 6 is a graph that illustrates the capacity of a screen device having a rotor with the novel rotor elements as disclosed herein and that of a prior art screen device having a rotor with conventional rotor elements, such as shown in FIGS. 1 a and 1 b.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIGS. 1 a and 1 b illustrate a conventional rotor element 10 in side view and as seen from above, respectively. The rotor element has a front surface 11 , a plane surface 12 parallel to the rotor surface, a shoulder 13 and a trailing surface 14 descending angularly towards the rotor surface. The front surface 11 is perpendicular towards the rotor surface and divided into two parts, which together form a plow-like surface. The abrupt front surface imparts a pressure shock to the pulp flow in the screen drum, by means of which the accept is pressed through the screen drum. After the shoulder, an intensive turbulence starts in the pulp flow under the effect of the suction impulse resulting as the taper of the trailing edge causes the surface of the rotor element to move radially away from the screen. The turbulence keeps the screen surface open and thus allows water to flow into the accept, contributing to thickening of the reject.
[0032] FIGS. 1 c and 1 d illustrate a novel rotor element 20 on the surface of a cylindrical rotor. The element has a front surface 21 , an upper plane 22 parallel to the rotor surface, a shoulder 23 and a trailing surface 24 descending curvedly towards the rotor surface. The sidewalls 27 and 28 of the trailing surface converge towards and at the back point 29 . The front surface 21 of the rotor element 20 is perpendicular towards the rotor surface and divided into two parts 25 and 26 , which together form a plow-like front surface 21 . The front surface and the upper plane 22 assist in guiding the pulp as a thin smooth film onto the screening surface, from where the accepted fiber fraction is passed to the accept side of the screen drum in a zone where the clearance between the screen drum and the rotor element is the smallest. After the shoulder the curved trailing surface 24 has a long gentle slope which minimizes the turbulence of the pulp flow to promote a homogeneous pulp flow that conforms to the curvature of the screening surface. The homogeneous pulp flow reduces the amount of water entering the accept side and thus minimizes the thickening disturbing the screening of the reject.
[0033] FIGS. 2 a to 2 d illustrate schematically preferred forms of a novel rotor element, both in side view ( FIGS. 2 a and 2 c ) and from above ( FIGS. 2 b and 2 d ). FIG. 2 a shows a rotor element 30 in the form of a protrusion on the surface 31 of the rotor, which protrusion can be formed on said surface or the element is attached to the surface by appropriate means known per se, such as by welding, with a screw and other attachment means. The views from above ( FIGS. 2 b and 2 d ) each show two different embodiments of the novel rotor element. The first rotor element embodiment is shown by a continuous line in FIGS. 2 b and 2 d , the front surface 32 is perpendicular in relation to the rotor surface, but the front edge 33 is curved, so that the energy consumption is decreased. After the front surface follows a plane 34 parallel to the rotor surface, which plane ends in a shoulder 35 . The trailing surface 36 is curved to promote laminar and smooth pulp flow between the screen and trailing surface and downstream of the shoulder. In this embodiment (continuous lines in FIGS. 2 b and 2 d ), the trailing surface has at least a first part 37 and a second part 38 , whereby the first part is closest to the shoulder and its sidewalls are substantially parallel to each other, while the sidewalls of the second part converge towards the back point 39 ,′ 54 , such that the opposite sidewalls converge at the back point or substantially converge such that the back point is a narrow back section that may be curved.
[0034] In the initial point of the curved trailing sidewalls of the rotor element the lag angle is preferably less than 10°, whereby an angle α is formed between a tangential plane T 2 intersecting said initial point of the curve and a tangential plane T 1 of the radius of curvature r 1 .
[0035] Another embodiment of the novel rotor element is shown by the dash lines in FIGS. 2 b and 2 d . In this another embodiment, the front surface of the rotor element is divided into two parts 40 and 41 or 56 and 57 (dash line), which together form a plow-like surface. Then the front edge has a wedge-like form. The sidewalls 42 or 58 of the trailing surface converge towards and to one of the back points 39 , 39 ′, 54 and 54 ′ essentially as early as starting from the shoulder 35 or 55 . A trailing surface converging starting from the shoulder can also be arranged in connection with a curved front surface or a wedge-like front surface, or a two-part trailing surface described in connection with the first embodiment can be arranged in connection to a wedge-like front surface.
[0036] According to an embodiment the rotor element can also be devoid of a shoulder, i.e. the pulp may as well contact directly a front surface and a trailing surface that curves therefrom towards the back point. This alternative is illustrated with dash lines 44 or 59 on the rotor's upper surface in FIGS. 2 a and 2 b . A rotor element's planar upper surface devoid of a shoulder can have an advantageous influence on energy consumption.
[0037] FIGS. 2 c and 2 d show a rotor element 50 is attached to surface 52 of the rotor via a support member 51 . The rotor element 50 is similar to the rotor element illustrated in FIGS. 2 a and 2 b , except the front surface 53 is curved, as shown in the side view of FIG. 2 c and the element is supported by a post 51 on the rotor surface 52 .
[0038] In accordance with FIG. 3 , a screen device 60 comprises an outer housing 62 , conduit 63 therein for incoming pulp and discharge conduits for accept 64 and reject 65 , a stationary screen drum 67 and an essentially cylindrical rotor 66 therein. The screen drum 67 can in principle be of any type, but the best results are obtained if a profiled screen drum is used. The operation of the screen device 60 is essentially the following: the fiber suspension is fed via conduit 63 inside the device, wherein the fiber suspension is passed into the gap between the screen drum 67 and rotor 66 . The accept flown through the apertures of the screen drum is discharged from conduit 64 , and the pulp flown to the lower end of the gap between the screen drum 67 and rotor 66 and thereout is discharged from reject conduit 65 .
[0039] Further, FIG. 3 shows that the surface of rotor 66 on the side of the screen drum 67 is provided with rotor elements 68 in the form of protrusions on the rotor surface. The rotor elements each have curved trailing surface with sidewalls that converge at a back point.
[0040] FIGS. 4 a and 4 b illustrates rotor elements 68 , 68 ′ arranged on the surface of a rotor 66 bent, whereby the rotor surface is shown in planar form for purposes of illustration. The novel rotor element 68 (such as shown in FIGS. 1 c and 1 d , and FIGS. 2 a to 2 d and 5 a to 5 f ) allows using a greater number of rotor elements 68 on one and the same circumferential sector without decreasing the goodness criteria of screening. Additional screening capacity can be obtained by locating more rotor elements on the same circumferential line around the rotor. Adding rotor elements may increase the feeding consistency. In contrast, conventional rotor elements cause strong cavitations and flow stall in the pulp flow over and after the trailing surfaces. The cavitations and stalling results in turbulence in the pulp flow that interferes with pulp flow over downstream rotor elements. The cavitation and stalling of the pulp flow, limits the number of conventional rotor elements that can be positioned on the same circumferential line around a rotor while providing effective screening.
[0041] FIG. 4 b illustrates a rotor element 68 ′ embodiment (the lower drawing), in which the novel rotor element is elongated in the circumferential direction. The arcuate length of the elongated element can be at least 35°, even 50°-200°. The number of elements on the same circumferential segment can be e.g. two.
[0042] FIGS. 5 a - 5 f show additional embodiments of a rotor element according to the invention in a way similar to that in connection with FIGS. 2 a - 2 d , as well as in side view ( FIGS. 5 a , 5 c and 5 e ) and from above ( FIGS. 5 b , 5 d and 5 f ).
[0043] In FIGS. 5 a and 5 b , a rotor element 70 is on the surface 71 of the rotor in form of a protrusion that can be formed in the said surface, or the element is fixed onto the surface by means known per se, such as by welding, with a screw etc. However, the front part 74 of the rotor element is clear of the rotor surface, so that there is a gap 75 between the rotor element and the rotor surface and that the front part is similar to a hydrofoil. Thus the pulp flow can pass it smoothly, i.e. without a major pressure shock. At the same time, the rotor element penetrates the pulp flow smoothly, whereby the flow is distributed more evenly to the capacity zone. This facilitates a smooth and efficient flow of the pulp onto the rotor element. The view from above ( FIG. 5 b ) illustrates two different embodiments. In the first embodiment (continuous line) the front edge 73 of the front surface 72 is curved. In the other embodiment the front surface is divided into two parts 75 and 75 ′ (dash line) that together form a wedge-like surface. Thus the front surface has a wedge-like shape. In accordance with the invention the trailing surface 77 is curved and its sidewalls 78 and 79 or 78 ′ and 79 ′ converge towards the back point 76 or 76 ′, respectively.
[0044] FIGS. 5 c and 5 d illustrate an alternative shape of a front part 82 of rotor element 80 on the rotor surface 81 . The rotor element is machined or gouged at the sides 83 of the front part 82 so that the flow is smoothly directed under the front part to the sides of the element. The purpose is to pierce the pulp flow with the rotor element so that a smooth flow onto the element is achieved. Otherwise the shape of the rotor element is similar to that of FIGS. 5 a - 5 b.
[0045] FIGS. 5 e and 5 f illustrate on alternative embodiment, wherein both the front part 85 and the back part 86 of the rotor element 84 are machined or gouged so that they are clear of the rotor surface 87 . The trailing surface 88 of the element is curved and its sidewalls converge towards the back point 89 . The view from above ( FIG. 5 f ) illustrates two different embodiments, in which the front edge 90 (continuous line) of the front surface is curved or the front surface is divided into two parts 91 and 91 ′ (dash line) that together form a wedge-like surface.
[0046] FIG. 6 illustrates the maximum functional capability of a screen having the novel rotor elements disclosed herein and a prior art screen in a pulp production line with normal equipment. The dash line illustrates the consistency of the reject as a function of feeding consistency, and the continuous line the specific energy consumption (OEK) of the rotor as a function of feeding consistency. The pulp in question is oxygen-delignified SWSA (softwood sulphate) pulp. Lines 1 illustrate a screen with the novel rotor elements and lines 2 a prior art screen. The device with the novel rotor elements operates at a significantly higher feeding consistency than the prior art device, and still the energy consumption is lower. Also, the thickening of the reject is lower in the device with the novel rotor elements, although it is operated at the same or a higher feeding consistency as the device with the prior art screen. The device with the novel rotor elements is further characterized in that lower rotor speeds can be used at the required feeding consistency, which decreases energy consumption.
[0047] The screen with novel rotor elements disclosed herein may provide at least the following advantages:
[0048] A. low thickening tendency of the reject.
[0049] B. high feeding consistencies can be used, e.g. in the apparatus disclosed herein had a feeding consistency of SW-pulp of 1.5% higher than the prior art device. As a result of this, the number of water cycles in the mill is decreased, need for pumping is decreased, apparatuses, such as containers, are required in decreased numbers, sizes of the apparatuses are decreased, pipe lines become shorter, the overall space requirement is decreased.
[0050] C. decreased energy consumption compared to prior art.
[0051] D. better running security of the screen, because cavitation is decreased, and
[0052] E. more reserve capacity.
[0053] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | In a screening device, a rotor element on a rotor coaxial with a cylindrical screen drum and a cylindrical screen including: an upper surface and a front face between the surface of the rotor and the upper surface, wherein the front face faces upstream into pulp flow through a gap between the screen drum and the cylindrical screen; a trailing surface extending downstream of the pulp flow from the upper surface, wherein the trailing surface tapers to the surface of the rotor and meets the surface of the rotor at a back region of the trailing surface, and opposite sidewalls extending between the trailing surface and the surface of the rotor, wherein the opposite sidewalls gradually converge towards the back region. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to wild bird feeders and methods of attracting wild birds for observation. In order to attract wild birds for the purpose of observation and study, bird feeders of various types have been developed. Bird feeders attract wild birds to a specific location by presenting an easily accessible supply of food. Wild birds have a great variety of feeding habits, consuming grains, seed as well as insects and other creatures. Prior bird feeders have been directed primarily at delivering seed or grains as feed to those bird species that each such food. Other feeders are designed to present other inert food forms such as suet. However, these devices are not successful in attracting birds which feed primarily on live insects. Bird feeders presenting grains and seed alone are not effective in attracting those bird species that feed predominantly on insects. Storage and presentation of live insects in a bird feeder poses difficulties not present with inert foods such as seeds or grains. Seeds and grains may be stored in bulk with a minimum of maintenance or protection. Live insects must be maintained in an environment which sustains them in order to be attractive to insect-consuming birds. At the same time, the insects must be presented in a manner to be visible and attract birds. While the prior art includes birdfeeders for presenting live insects for attracting wild birds, none include a means for sustaining and maintaining the insects. What is needed is a bird feeder for maintaining and presenting live insects.
SUMMARY OF THE INVENTION
The present invention provides a bird feeder and method of presentation for live insects as a wild bird attractant. The present bird feeder includes a food chamber having a well for retaining a quantity of a sustaining media. The media is selected for sustaining for a period of time a quantity of insects, preferably what are commonly known as mealworms. The food chamber includes entrance holes that are sized to allow access by birds without their being able to entirely entering the chamber. Near the food chamber a presentation platform is provided for presenting a second quantity of live insects. In the present methods of use, a quantity of live insects are established in sustaining media in the feeder well as described. A second quantity of insects are placed on the presentation platform in a position to be clearly visible from locations distant from the bird feeder. The bird feeder is then positioned in a location known to be frequented by wild birds. Birds are initially attracted by observing the second quantity of insects on the presentation platform. Upon arriving at the bird feeder, birds then observe and investigate the insects in the sustaining media. Because the insects in the media are not as readily found and consumed, the birds are induced to remain at the feeder and may be readily observed for a period of time.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of the present invention.
FIG. 2 is a cross section view of the embodiment of FIG. 1 with the addition of live insects as used in the present methods.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 and 2 depict, respectively, perspective and cross-section views of one embodiment of a birdfeeder 10 according to the present invention. The birdfeeder 10 includes a food chamber 12 having one or more access holes 14 . The access holes 14 are offset from a bottom 15 of the chamber 12 . The portion of the chamber below the bottom edge of the access holes 14 forms a well 16 for receiving insects together with a sustaining media. In use, insects 17 are retained in a media 13 to sustain them alive for a period of time. The depth of the media 13 is preferably sufficiently small that the insects 17 can not completely conceal themselves within the media. In this way, visiting birds outside the chamber may more easily view and identify the insects presented. The preferred insect is what is commonly known as a mealworm or mealy worm. The type of media 13 and appropriate depth of the well 16 is in part dependent upon the nature of the insect to be used. For mealworms grain-based media can be used including, but not limited to, oat meal, brans, and corn meal. Other types of media may be selected as may be appropriate for other insects. Preferably, the media fills a well 16 having a depth in the range of ½ to ¾ inches. Less than this range will result in the insects attempting crawl out of the media due to insufficient coverage. While a well and media depth much greater than this range decreases the visibility of the mealworm Mealworms placed in a grain-based media in the manner described can be sustained a longer period of time that exposed mealworms. Mealworms which are not provided a sustaining media will most likely die before they will be found and eaten by birds. To preclude frequent replacement of the insects it may be necessary to supply the feeder with 50 or more mealworms, which quantity are sustainable in the birdfeeder configuration described.
The chamber 12 is covered at the top by a rain cover 18 which extends outward from, and overhangs, the chamber 12 . The rain cover 18 is solid and prevents rain from entering the access holes 14 . The rain cover 18 is similar to those used with previously known birdfeeders. Below the food chamber is a presentation platform 20 having an upper presentation surface 21 , through-holes 22 for drainage, and a side wall 24 to prevent insects from leaving the presentation platform. A side wall height of 1.5 inches has been found effective. A perching element in the form of a horizontal lip 28 at the top of the side wall 24 is provided for birds to conveniently light on. The lip 28 is positioned at a distance ¾ to 1 inch relatively below the bottom edge of the access holes 14 to encourage viewing by perching birds of the inside of the food chamber 12 through the access holes 14 . Other perching structures such as horizontal posts are also contemplated. The size and configuration of the presentation platform 20 is such as to ensure visibility of the presentation surface from points distant from the birdfeeder. The size of the access holes is selected to allow viewing and access by birds to the chamber without allowing birds to completely enter the chamber. Because viewing of the birds by the user is the objective of this device, it is desired to force a visiting bird to retrieve food from the chamber and then consume it from the exterior perch. For birds of the size of a common bluebird, a circular access hole having a diameter of about ½ to 1 inch is preferred. In the figures the access hole is slightly oval in shape, having a nominal width of ¾ inch and height of 1 inch. Alternative access holes have other shapes including slots which allow wider visibility of the chamber interior. However, the objective of allowing limited access to the chamber interior is preferably maintained. While access holes may be located at any circumferential position on the chamber, they most preferably are located only on any one diametrical side. This allows the birdfeeder to be positioned such that birds may only obtain food from the chamber from a location visible to a user at a predetermined relative position. That is, birds cannot “hide” from the user by entering the chamber from a side opposite the viewing user.
The cover 18 , chamber 12 and platform 20 shown in the figures are connected by a center post 30 which is formed of multiple sections that interconnect via internal female thread and respective threaded male portions that extend through the various bird feeder structures. Other methods and structures for connecting the bird feeder structures will be obvious to those skilled in making such devices. The birdfeeder may be formed of any of a variety of materials including wood, metals and plastics. The manner of making these structures will also be obvious. In the figures, the bird feeder principal structures are generally circular in shape in horizontal views. Alternative shapes, such as square are also applicable.
In operation, the above birdfeeder is prepared by depositing a quantity of mixed media and live insects 17 (mealworms in FIG. 2) into the well of the food chamber 12 as shown in FIG. 2 . The cover 18 is preferably easily removable for this purpose. A second quantity of live insects 19 are then placed onto the presentation platform 20 , preferably without media or any other matter which might obstruct the insects 19 from being viewed. As most insect-feeding birds of interest hunt by sight, it is important that the insects on the presentation platform 20 be easily seen from surrounding locations. The birdfeeder is positioned to be seen both by birds in the surrounding environs and by the user. Subject birds are first attracted by the sight of the insects on the presentation platform Upon arriving to eat these insects, they easily view the chamber interior and are induced to search for insects within the media. If the media is of proper depth, portions of insects within the media will be visible and particularly attract the attention of the birds. Because the birds remain outside the birdfeeder chamber while they search the media and eat the insects, they are available for viewing by the user. In the instances where the present birdfeeder contains insects within the food chamber 12 but not on the presentation platform 20 , birds may still be attracted to the feeder or incidentally light there. In such cases, they will be induced to remain by their interest in the insects within the chamber. In this way, some of the benefits of the feeder and present methods are gained without presenting “bait” insects on a presentation platform
Other insects which may successfully be used to attract birds in the present birdfeeder and with the present methods include, but are not limited to, larvae and pupae of insects such as flies. Due to the nature of the feeder, the insect must be of a type that will be restrained and sustained in a solid media as described and consequently will not, by its nature, quickly seek to leave the feeder.
The preceding discussion is provided for example only. Other variations of the claimed inventive concepts will be obvious to those skilled in the art. Adaptation or incorporation of known alternative devices and materials, present and future is also contemplated. The intended scope of the invention is defined by the following claims. | A novel birdfeeder and method of attracting wild birds is provided. A birdfeeder provides a food chamber having a well in which live insects are maintained in a sustaining media. Viewing of and access to, the insects is allowed through access holes which constrain birds from fully entering the food chamber. A presentation platform adjacent the food chamber is used to present a second quantity of insects which are visible to distant birds. The birds are initially attracted to the exposed insects and subsequently induced to remain at the feeder by the insects in the food chamber. Insects such as mealworms are used to attract primarily insect-feeding wild birds such as blue birds. | 0 |
TECHNICAL FIELD
[0001] The invention relates generally to photoacoustic sensors and, more particularly, to active detection techniques for photoacoustic sensors.
BACKGROUND
[0002] Photoacoustic sensors have been employed in the past for detection of gas species. Turning to FIG. 1 , an example of a conventional photoacoustic sensor system 100 can be seen. This system 100 generally comprises a laser 102 , optics 104 , and an acoustic resonance chamber 106 , tuning fork 108 , lock-in amplifier 110 , and function generator 112 . In operation, the function generator 112 provides a drive signal to the laser 102 so as to modulate the beam emitted by the laser 102 . The optics 104 can focus the beam along optical path 114 into the acoustic resonance chamber 106 (which contains a gas sample). By virtue of the photoacoustic effect, the modulated laser beam will cause the gas sample in the acoustic resonance chamber 106 to expand and relax if the wavelength of the laser matches the molecular resonance of the gas sample, which, in turn, causes the acoustic resonance chamber 106 to vibrate. Tuning fork 108 (which is generally placed in proximity to the acoustic resonance chamber 106 and which is generally a high-Q resonator) converts the vibrational signatures to electrical signals which is then amplified by the lock-in amplifier 110 (which also can receive the drive signal from the function generator 112 ). Based on the vibrational signatures, the identities and concentrations of gas species within the gas sample can be isolated.
[0003] This arrangement, however, does have some problems. For example, because this system 100 , uses passive detection, the system 100 suffers from errors due to amplifier noise (i.e., used to amplify the signal from tuning fork 108 ) and ambient thermal noise as well as frequency drift and inaccuracy of tuning fork natural resonance. Therefore, there is a need for an improved photoacoustic sensor.
[0004] Some other conventional systems are: U.S. Pat. No. 4,184,768 U.S. Pat. No. 4,818,882; U.S. Pat. No. 5,479,259; U.S. Pat. No. 6,106,245; U.S. Pat. No. 7,245,380; U.S. Pat. No. 7,387,021; U.S. Pat. No. 7,520,158; U.S. Pat. No. 7,605,922; U.S. Pat. No. 7,797,983; U.S. Patent Pre-Grant Publ. No. 2008/0252891; U.S. Patent Pre-Grant Publ. No. 2009/0320561; U.S. Patent Pre-Grant Publ. No. 2010/0027012; and European Patent No. EP0685728.
SUMMARY
[0005] A preferred embodiment of the present invention, accordingly, an apparatus is provided. The apparatus comprises a transmitter that generates a modulated energy beam along an axis; an acoustic resonance chamber that is generally coextensive with the axis and that receives the modulated energy beam; an acoustic transducer that is placed in proximity to the acoustic resonance chamber; drive circuitry that is electrically coupled to the transmitter, wherein the drive circuitry is adapted to operate the acoustic resonance chamber based on the resonant frequency of the acoustic transducer operating in an active resonance mode; and a detector that is electrically coupled to the acoustic transducer and the drive circuitry, wherein the detector detects the existence of resonance of the acoustic resonance chamber by detecting a change in the frequency or amplitude of an oscillator formed by the drive circuitry and the acoustic transducer.
[0006] In accordance with a preferred embodiment of the present invention, the detector further comprises a frequency counter.
[0007] In accordance with a preferred embodiment of the present invention, the detector further comprises a phase detector.
[0008] In accordance with a preferred embodiment of the present invention, the detector further comprises a phase-locked loop (PLL).
[0009] In accordance with a preferred embodiment of the present invention, the detector further comprises an analog-to-digital converter (ADC).
[0010] In accordance with a preferred embodiment of the present invention, the transmitter further comprises: an emitter that emits the modulated energy beam, wherein the oscillator gates the emitter at a gating frequency; and a focusing member that is generally coextensive with the axis so as to focus the modulated energy beam.
[0011] In accordance with a preferred embodiment of the present invention, the emitter further comprises a laser diode, and wherein the modulated energy beam further comprises a modulated laser beam.
[0012] In accordance with a preferred embodiment of the present invention, the emitter further comprises an antenna that is adapted to emit RF radiation that generally matches a predetermined molecular resonant frequency, and wherein the focusing member further comprises a waveguide.
[0013] In accordance with a preferred embodiment of the present invention, the detector is electrically coupled to the drive circuitry to control the gating frequency so that the gating frequency generally matches the resonant frequency of the acoustic resonance chamber.
[0014] In accordance with a preferred embodiment of the present invention, the transmitter further comprises: a frequency generator that generates frequencies at resonant frequencies of molecules of a gas sample; the oscillator having the acoustic transducer and the drive circuitry as a negative resistance; an emitter that is electrically coupled to the frequency generator and that emits the modulated energy beam, wherein the oscillator modulates the frequency generator at a modulating frequency; and a focusing member that is generally coextensive with the axis so as to focus the modulated energy beam.
[0015] In accordance with a preferred embodiment of the present invention, the detector is electrically coupled to the drive circuitry to control an oscillating frequency formed by the transducer and the drive circuitry so that the modulating frequency generally matches the resonant frequency of the acoustic resonance chamber.
[0016] In accordance with a preferred embodiment of the present invention, the detector is electrically coupled to the drive circuitry to control the resonance chamber so that the chamber resonance generally matches the frequency of oscillation formed by the acoustic transducer and the drive circuitry.
[0017] In accordance with a preferred embodiment of the present invention, the drive circuitry further comprises: a current source that is electrically coupled to the acoustic transducer; and an NPN transistor that is electrically coupled to the current source at its collector and the acoustic transducer at its base.
[0018] In accordance with a preferred embodiment of the present invention, the drive circuitry further comprises: an inverting gain element that is electrically coupled between a first node and a second node; a first resistor that is electrically coupled between the first node and the second node; the acoustic transducer is electrically coupled between the first node and the second node; a first capacitor that is coupled to the first node; and a second capacitor that is coupled to the second node.
[0019] In accordance with a preferred embodiment of the present invention, the first and second capacitors further comprise first and second variable capacitors.
[0020] In accordance with a preferred embodiment of the present invention, the acoustic resonance chamber further comprises a tuning member that is adapted to adjust the resonant frequency of the acoustic resonant chamber.
[0021] In accordance with a preferred embodiment of the present invention, an integrate circuit (IC) is provided. The IC comprises a substrate; a transmitter that is formed on the substrate and that is adapted to generate a modulated energy beam along an axis; an acoustic resonance chamber that is formed on the substrate, that is generally coextensive with the axis and that is adapted to receive the modulated energy beam; a transfer system that is formed on the substrate and that is in fluid communication with the acoustic resonance chamber, wherein the transfer system is adapted to transfer fluid samples into the acoustic resonance chamber; an acoustic transducer that is formed on the substrate and that is placed in proximity to the acoustic resonance chamber; drive circuitry that is formed on the substrate and that is electrically coupled to the transmitter, wherein the drive circuitry is adapted to operate the acoustic resonance chamber based on the resonant frequency of the acoustic transducer operating in an active resonance mode; and a detector that is formed on the substrate and that is electrically coupled to the acoustic transducer and the drive circuitry, wherein the detector detects the existence of resonance of the acoustic resonance chamber by detecting a change in the frequency or amplitude of an oscillator formed by the drive circuitry and the acoustic transducer.
[0022] In accordance with a preferred embodiment of the present invention, the acoustic transducer further comprises a microelectromechanical systems (MEMS) microphone.
[0023] In accordance with a preferred embodiment of the present invention, transfer system further comprises: an input port that is in fluid communication with the acoustic resonance chamber; a first MEMS valve that is located between the input port and the acoustic resonance chamber; a output port that is in fluid communication with the acoustic resonance chamber; a second MEMS valve that is located between the output port and the acoustic resonance chamber; and a MEMS pump that is in fluid communication with the output port.
[0024] In accordance with a preferred embodiment of the present invention, the acoustic resonance chamber further comprises a tuning member that is adapted to adjust the resonant frequency of the acoustic resonant chamber.
[0025] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
[0027] FIG. 1 is a block diagram of a conventional photoacoustic sensor system;
[0028] FIGS. 2 and 3 are block diagrams of examples of portions of a photoacoustic sensor system in accordance with a preferred embodiment of the present invention; and
[0029] FIG. 4 is a block diagram of an example of a photoacoustic sensor system using the portions of FIG. 2 or FIG. 3 .
DETAILED DESCRIPTION
[0030] Refer now to the drawings wherein depicted elements are, for the sake of clarity, not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
[0031] Turning to FIG. 2 , an example of a portion 200 - 1 of a photoacoustic sensor can be seen. As shown, portion 200 generally uses an active resonance circuit or drive circuitry 206 - 1 to operate acoustic transducer 204 (i.e., piezoelectric crystal or microelectromechanical (MEMS) microphone) in an active resonance mode. In addition to the drive circuit 206 - 1 , the portion also generally comprises a detector 202 and transmitter 210 . The transmitter 210 can include both an emitter (i.e., diode laser or RF transmitter) and a frequency generator. Additionally, the drive circuit 206 - 1 generally comprises a current source 208 and a transistor Q 1 (which can, for example, be an NPN transistor), while the resonator (not shown) can generally include an acoustic transducer 204 that is placed in proximity (i.e., 0.1 μm to 10 mm) to an acoustic resonance chamber (i.e., 106 ) such that the acoustic transducer 204 is able to vibrate or oscillate.
[0032] In operation, the drive circuitry 206 - 1 actively drives the acoustic transducer 204 so as to control the modulation of the beam used to drive the resonant chamber. Generally, a current is provided from current source 208 (from voltage rail VCC), while resistor R 1 and transistor Q 1 drive the acoustic transducer 204 . Because the voltage-to-phase noise up conversion is generally filtered by the resonator (which is generally a high-Q resonator), the timing jitter is low and the frequency shift can be reliably detected. The detector 202 (which, for example, can be a phase detector or phase locked loop (PLL)) such that the detector 202 detects the existence of resonance of the acoustic resonance chamber by detecting a change in the frequency of the Pierce oscillator formed by the drive circuitry 202 (which can offer negative resistance) and the acoustic transducer 204 . Typically, a reference resonator circuit or PLL can be used to establish a reference frequency to perform phase detection, where the first derivative of phase difference can be used to detect the frequency change. This frequency change can then be used to determine gas species present in a gas sample. Moreover, because system 200 - 1 generally operates the transducer in an active resonance mode, the oscillation and the modulation frequency track each other such that the detection of acoustic chamber resonance can be at the maximum sensitivity point of the transducer. Alternatively, the detector 202 may include a frequency counter.
[0033] Turning to FIG. 3 , another example of a drive circuitry 206 - 2 can be seen (which is used within portion 200 - 2 and which is also a Pierce oscillator). As shown, this drive circuitry 206 - 2 generally comprises an inverter 302 , resistors R 2 and R 3 , capacitor C 1 and variable capacitor C 2 (which, for example, can be one or more varactors or a switched capacitor bank). Alternatively, capacitor C 1 can also be a variable capacitor. A difference between drive circuitry 206 - 1 and 206 - 2 is that the drive circuitry 206 - 2 can “tune” the oscillator 204 by adjusting or varying the capacitance of capacitor C 2 . As an alternative, a Colpitts oscillator can be used as well.
[0034] In FIG. 4 , an example of an IC 400 that employs a photoacoustic sensor system formed on a substrate 401 in accordance with a preferred embodiment of the present invention can be seen. IC 400 generally comprises drive circuitry 206 - 1 or 206 - 2 (hereinafter referred to as drive circuitry 206 ), detector 202 , transmitter 210 (which, as shown and for example, can be a frequency generator 402 and emitter 404 ), focusing member 406 (which, for example, can be optics or a waveguide), acoustic transducers 408 and 410 (which, for example and as shown, can be a quartz crystal or MEMS microphones), acoustic resonance chamber 424 , tuning member 426 , input port 412 , output ports 418 and 422 , pump 420 (which, for example and as shown, can be a MEMS pump, such as those described in U.S. Pat. No. 6,106,245, which is incorporated by reference), and valves 414 and 416 (which, for example and as shown, can be MEMS valves). In operation, the transfer system or, collectively, valves 414 and 416 and pump 420 (which are in fluid communication with each other and the external atmosphere) can be used to introduce a gas sample to acoustic resonance chamber 424 and adjust the pressure within the acoustic resonance chamber to a desired pressure (i.e., 750 Torr). With the gas sample in place in this example, the frequency generator 402 generates an RF signal at resonant frequencies of molecules of the gas sample. The RF signal is then modulated by the drive circuitry 206 in either frequency generator 402 or emitter 404 so that a modulated beam (i.e., infrared laser, ultraviolet laser, visible light laser, or RF radiation) is emitted by the emitter 404 at a gating frequency, which is further focused along optical axis or path 428 by focusing member 406 , so as to interact with the gas sample. The transducers 408 and 410 (i.e., quartz crystal or MEMS microphones) are placed in proximity to the acoustic resonance chamber 424 so that the detector 202 can detect the existence of resonance of the acoustic resonance chamber by detecting a change in the frequency of the oscillator formed by the drive circuitry 206 and the acoustic transducers 406 and 408 . Additionally, the drive circuitry 206 and/or detector 202 can also provide a signal to control the tuning member 426 so as to vary the natural frequency of the acoustic resonance chamber 424 by, for example, extending or reducing the length of a generally cylindrical acoustic resonance chamber 242 .
[0035] Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | Traditional photoacoustic sensors generally operate in a passive mode, which can degrade the performance. Here, however, a photoacoustic sensor has been disclosed that operates an acoustic resonance chamber and a transducer in an active mode so as to avoid the problems associated with traditional photoacoustic sensors; in particular, because the acoustic resonance chamber operates at near atmospheric pressure such as 100's Torr as opposed to 1 m Torr type of pressure for radio spectroscopy, the sensor is allowed to be scaled to operate on an integrated circuit or IC. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method for operating an antenna device of a user equipment, especially to methods for finding a base station or an access point of a wireless communication network with a user equipment, for example for establishing a communication connection between the user equipment and the wireless communication network. The present invention relates furthermore especially to operating an antenna device of a user equipment providing a configurable transmission pattern.
BACKGROUND OF THE INVENTION
[0002] The use of higher frequency bands for mobile communication is investigated due to the potential larger bandwidth availability. Such higher frequency bands are also called millimeter waves and may have a frequency of 10 GHz up to about hundreds of GHz. One issue that arises with these higher frequency bands is the fact that the wavelength is very small, and in order to achieve decent performance, multiple antennas, e.g. in the shape of an array, may be needed in the user equipment, for example a mobile telephone. Using such an antenna arrangement may offer a high antenna gain with a correct phasing of the antennas. However, correct phasing of the antennas is also a challenge. For a large number of antennas, the phasing narrows the antenna radiation into a beam and this beam needs to be directed towards the base station. Therefore, an iterative algorithm may be used for aligning the antenna arrangements at the base station and the user equipment. For example, the antenna arrangement at the base station and the antenna arrangement at the user equipment may scan for each other until a link can be established. Obviously, mobility of the user equipment may cause problems with such algorithms. Therefore, there is a need for an improved configuration of the antenna arrangement at the user equipment to set up a communication link to a base station or an access point of the wireless communication network.
SUMMARY OF THE INVENTION
[0003] According to an embodiment of the present invention, a method for operating an antenna device of a user equipment is provided. The antenna device provides a configurable transmission pattern. For example, the antenna device comprises an antenna array or any other arrangement of a plurality of antennas and a direction of a high reception sensitivity may be configurable. According to the method, an orientation of the user equipment is determined with an orientation determining sensor of the user equipment. The orientation determining sensor may comprise for example a gyrometer, a gravity sensor or a compass. The transmission pattern of the antenna device is configured based on the determined orientation. Especially, an orientation of the user equipment with respect to a geological horizon may be determined and the transmission pattern of the antenna device is configured based on the determined orientation of the user equipment with respect to the geological horizon. Therefore, the orientation determining sensor in the user equipment is used to prioritize antenna arrangement beams steering in the horizontal plane for an arbitrary user equipment orientation. As a base station or an access point is usually located along the horizontal plane, i.e. the horizon, a likelihood for finding the base station or the access point may be increased by configuring the transmission pattern of the antenna device accordingly. Additionally, if the user equipment looses contact to the base station, based on the determined orientation the user equipment may use the same elevation as before to re-establish the contact to the base station. In this context, the term “base station” may comprise any kind of base stations, e.g. base stations of a cellular mobile communication network, access points of a wireless local area network, or any other hub. In a device-to-device communication, the “base station” may also relate to another user equipment, as in a device-to-device communication also other user equipments may be contacted preferably in the horizontal plane. Furthermore, as user equipments, like e.g. mobile phones, usually comprise sensors for determining an orientation of the user equipment, for example a sensor for detecting what is up and down, the orientation of the user equipment may be determined at low additional cost.
[0004] In this description, the term “transmission pattern” relates to a configuration of an antenna or an antenna arrangement determining a reception sensitivity in a certain direction and/or a sending characteristic in a certain direction or both. Therefore, the term “transmission” may relate to receiving signals, to sending signals or to both.
[0005] According to an embodiment, the transmission pattern of the antenna device is configured such that the transmission pattern is levelled along the geological horizon. Especially for frequencies below about 30 GHz the number of antenna elements is expected to be in a lower range, for example in a range of 4 to 16 antennas, and possibly in a one dimensional arrangement. In this case it is possible to configure the transmission pattern and thus the coverage of the antenna device along the horizon. For example, the transmission pattern of a single antenna or the antenna arrangement may be in the form of a disk, a so called donut, or at least a part of such a disk, and the axis of the disk may be levelled by configuring the antenna arrangement such that it is perpendicular to the horizon providing a high sensitivity and radiation of the antenna along the horizon. Levelling the transmission pattern along the horizon as it is used in this description includes a levelling approximately to the horizon, e.g. in an angle of up to +/−20 to 30 degrees with respect to a horizontal direction.
[0006] According to another embodiment, the transmission pattern of the antenna device is configured such that an antenna beam scan is performed along the geological horizon. At higher frequencies, for example at frequencies above 30 GHz, the number of antenna elements is expected to be higher, for example much higher than 10. Consequently, the directivity of the antenna arrangement will increase. Therefore, the determined orientation of the user equipment is utilized to initially scan the horizontal plane or at least prioritize it, to find a base station or an access point. This may decrease the log in time for the user equipment when a communication link is set up between the user equipment and a wireless communication network, thus improving the power efficiency of the user equipment and increasing reliability and availability, for example during a cell change.
[0007] According to another embodiment, a method for finding a base station or an access point of a wireless communication network with a user equipment is provided. The user equipment comprises an antenna device providing a configurable transmission pattern. The term “configurable transmission pattern” is used to indicate the ability of the antenna device to change a direction of a highest reception sensitivity or a direction of a highest radiation due to a configuration. For example, in case the antenna device comprises a plurality of antenna elements arranged in a one dimensional arrangement, an at least partially disk shaped transmission pattern is provided whose orientation may be changed due to the configuration. Furthermore, in case the antenna elements are arranged in a two dimensional arrangement, a pencil beam shaped transmission pattern may be provided whose direction may be changed due to the configuration. According to the method, an orientation of the user equipment with respect to a geological horizon is determined with an orientation determining sensor of the user equipment. Based on the determined orientation, the transmission pattern of the antenna device of the user equipment is levelled along the geological horizon. Therefore, a likelihood of finding the base station or the access point may be increased.
[0008] According to a further embodiment, a method for finding a base station or an access point of a wireless communication network is provided. The method may be performed by a user equipment comprising a plurality of antenna elements arranged in a two dimensional arrangement providing a configurable pencil beam shaped transmission pattern. According to the method, an orientation of the user equipment is determined with respect to a geological horizon with an orientation determining sensor of the user equipment. An environment of the user equipment is scanned with the pencil beam shaped transmission pattern in various directions for finding the base station or the access point, respectively. Based on the determined orientation of the user equipment, a direction of the geological horizon is scanned with a higher priority than other directions.
[0009] According to yet another embodiment, a user equipment for a wireless communication network is provided. The user equipment comprises an antenna device for receiving and sending radio frequency signals from and to a base station or an access point of the wireless communication network. The antenna device provides a configurable transmission pattern. For example, a direction of a highest sensitivity of the antenna device may be configurable. The user equipment comprises furthermore an orientation determining sensor for determining an orientation of the user equipment. Especially, the orientation determining sensor may provide an information concerning the orientation of the user equipment with respect to a horizon or the direction of gravity. Therefore, in case the user equipment is moved by a user, for example when the user equipment is rotated by the user, a current orientation of the user equipment may be determined by the orientation determining sensor. The user equipment comprises furthermore a processing device configured to configure the transmission pattern of the antenna device based on the determined orientation. Therefore, the transmission pattern of the antenna device may be aligned or levelled such that a high sensitivity or radiation of the antenna device along the horizon may be provided. As a base station or an access point is usually arranged along the horizon, setting up a communication link between the user equipment and a base station or an access point may be facilitated.
[0010] According to an embodiment, the user equipment comprises for example a mobile telephone, a mobile computer, a personal digital assistant, a tablet computer, a television set, a monitor, or a projector. E.g., a projector may know from sensors or configuration if it is installed at a ceiling, wall or on a desk and the transmission pattern may be configured based on this information.
[0011] Although specific features described in the above summary and the following detailed description are described in connection with specific embodiments and aspects of the present invention, it should be understood that the features of the exemplary embodiments and aspects may be combined with each other unless specifically noted otherwise.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention will now be described in more detail with reference to the accompanying drawings.
[0013] FIG. 1 shows schematically a user equipment according to an embodiment of the present invention.
[0014] FIG. 2 shows a transmission pattern of a single dipole antenna.
[0015] FIG. 3 shows a transmission pattern of a row antenna.
[0016] FIG. 4 shows a transmission pattern of a two dimensional antenna arrangement.
[0017] FIG. 5 shows a flowchart comprising method steps of a method for operating an antenna device of a user equipment according to an embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0018] In the following, exemplary embodiments of the present invention will be described in more detail. It is to be understood that the features of the various exemplary embodiments described herein may be combined with each other unless specifically noted otherwise. Any coupling between components or devices shown in the figures may be a direct or an indirect coupling unless specifically noted otherwise.
[0019] FIG. 1 shows a user equipment 10 arranged in an environment of a base station 20 . The user equipment 10 may comprise for example a mobile telephone, especially for example a so called smartphone. The user equipment 10 comprises an antenna device 11 , an orientation sensor 12 and a processing device 13 . The antenna device 11 comprises a plurality of antennas or antenna elements 14 . The base station 20 may be a base station of a cellular wireless communication network. A communication between the user equipment 10 and the base station 20 may be accomplished via a radio frequency communication in a frequency band of 10 GHz up to hundreds of GHz, called millimeter wave band. Due to the small wavelength and in order to achieve an appropriate performance, multiple antennas in the shape of an arrangement may be needed in the user equipment. With a correct configuration of the antennas, especially with a correct phasing of the antennas, a high antenna gain may be achieved. However, this configuration may narrow the antennas' radiation and reception pattern, for example into a beam. This beam needs to be directed towards the base station. Typical sending and reception patterns of different antenna arrangements will be described in the following in connection with FIGS. 2 to 4 .
[0020] FIG. 2 shows a transmission pattern of a single dipole antenna. As can be seen from FIG. 2 , an isotropic pattern around an antenna axis is obtained, which has the shape of a disc or donut having its axis arranged in the Z-direction as indicated in FIG. 2 . When the antenna is placed with its top up, that means that the antenna is arranged perpendicular to a geological horizon, there is a high reception sensitivity and a high radiation along the antenna axis and a good reception or coverage along the horizon.
[0021] A transmission pattern of a one dimensional antenna arrangement is shown in FIG. 3 . The transmission pattern may be a disk or donut like pattern or a segment of a disk or donut like pattern for a typical row antenna. Depending on the configuration of the antenna arrangement an orientation of the disk shaped pattern may be changed as required. It is to be noticed that a one dimensional arrangement may have only one degree of freedom for levelling the transmission pattern. For example, it may be possible only to level the transmission pattern in one direction, e.g. along the X-Y plane, and if the user equipment is tilted in the X-Z plane there is nothing to level with a one dimensional array having the X direction as the axis. However, if the user equipment is tilted in the X-Y plane, this may be compensated by a corresponding levelling.
[0022] FIG. 4 shows a pencil beam pattern of a two dimensional antenna arrangement, e.g. a plurality of antennas may be arranged in an array of rows and columns. The direction of the pencil beam depends on the configuration of the antenna arrangement.
[0023] In a typical environment of the user equipment 10 and the base station 20 , the base station 20 is located along a horizontal plane 30 with respect to the user equipment 10 . In other words, usually the base station 20 is arranged along a geographical horizon. As shown in FIG. 1 , the user equipment 10 comprises the orientation sensor 12 which may comprise for example a gyrometer, a gravity sensor or a compass. The orientation sensor 12 may be configured to determine an orientation of the user equipment 10 with respect to the geographical horizon or horizontal plane 30 . User equipments, like for example mobile telephones, tablet computers and so on, usually comprise such orientation sensors, for example for aligning image outputs or for gaming applications. The processing device 13 utilizes information from the orientation sensor 12 for configuring the antenna device 11 .
[0024] For example, as shown in FIG. 5 , in step 51 the processing device 13 may determine a current orientation of the user equipment 10 , and a transmission pattern of the antenna device 11 is configured depending on the determined orientation in step 52 . In particular, the processing device 13 may use the orientation sensor 12 to adaptively level the antenna transmission pattern along the horizon 30 . Therefore, the antenna device can be tuned to cover the horizontal plane 30 and the base station 20 may be found and contacted reliably.
[0025] In particular for antenna arrangements at frequencies below for example 30 GHz, the number of antenna elements may be in a lower range of 4 to 16 and may be arranged in a one dimensional arrangement. The disk shaped pattern or segment of a disk as shown in FIG. 3 may be achieved by the one dimensional antenna arrangement. Depending on the information from the orientation sensor 12 the processing device 13 optimizes the coverage of the one dimensional antenna arrangement along the horizon 30 .
[0026] For antenna arrangements at frequencies above for example 30 GHz, the number of antenna elements may be larger, for example much larger than 10 or 20 and may be arranged in a two dimensional arrangement having a pencil beam shaped transmission pattern as shown in FIG. 4 . Consequently, the directivity will increase. In this case, an algorithm may be utilized that initially scans the horizontal plane 30 or at least prioritizes the horizontal plane 30 . Hence, a time for finding the base station 20 may be shortened thus improving operation reliability and power efficiency. | The present invention relates to a method for operating an antenna device of a user equipment, a method for finding a base station or an access point of a wireless communication network with a user equipment, and a user equipment for a wireless communication network. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of PCT application No. PCT/IBO2/03292, entitled “STABILISED POLYESTER COMPOSITIONS AND MONOFILAMENTS THEREOF FOR USE IN PAPERMACHINE CLOTHING AND OTHER INDUSTRIAL FABRICS”, filed Jul. 19, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention.
[0003] The present invention relates to stabilized polyester compositions and monofilaments thereof for use in papermachine clothing and other industrial fabrics.
[0004] 2. Description of the Related Art.
[0005] Monofilaments manufactured from polyethylene terephthalate (or PET) are used extensively in the production of papermachine clothing and other industrial fabrics. A paper machine typically includes three sections. In the forming section, where the cellulosic fibers are presented to a forming fabric in the form of a slurry, the fabrics are predominantly constructed from polyester monofilaments, more specifically PET. In the forming section of the papermachine the temperature rarely exceeds 60° C. and the fabric is subjected to severe wear from suction boxes used to withdraw water from the paper web, such that the fabric life is seldom over 120 days. The paper sheet is transferred from the forming section into the press section of the papermachine and at this point the solids content of the slurry is approximately 20%. Here, the paper sheet passes through a series of nip rolls or shoe presses, and due to the need for resilience, polyamides have been the material of choice. The paper sheet has about 40% solids content as it is transferred from the press section into the dryer section of the papermachine.
[0006] In the dryer section, a textile fabric holds the paper sheet against steam-heated cylinders. The temperature of the cylinder surface can exceed 120° C. and the evaporation of water from the sheet ensures that the relative humidity remains at 100%. Fabrics composed of PET are conventionally used for most dryer fabric applications. However, towards the end of the paper machine, as the solids content approaches 80 to 90%, the cooling effect of the evaporation is reduced and the temperature to which the fabric is actually exposed increases such that the PET fabric is now subjected to significant degradation. In most applications, the life of a typical PET fabric can be in excess of 12 months. However, under these extreme conditions service life is reduced significantly.
[0007] In order to extend the service life of dryer fabrics exposed to these conditions, suppliers to the industry have used an array of materials as the constituent material of the dryer fabric. Polyphenylene sulphide (or PPS) provides excellent thermal, hydrolytic and oxidative stability. However, the PPS polymer is significantly more expensive than PET. Monofilament extrusion of PPS is more problematic, leading to a higher percentage of product rejections and therefore higher production costs.
[0008] Copolyesters derived from 1,4-cyclohexane dimethanol, terephthalic acid, isophthalic acid and esters thereof, have been suggested as a cheaper alternative. U.S. Pat. No. 5,169,499 teaches the use of such copolyesters to improve the hydrolytic stability of papermachine clothing. The large cyclohexane moiety present in the polymer backbone serves to provide steric hindrance to the hydrolytic cleavage of the ester bond. However, the cyclohexane ring also serves to increase the susceptibility of such polyesters to oxidative degradation. It is generally accepted that the oxidation of polymers follows a free radical chain reaction mechanism that is initiated by abstraction of a hydrogen atom from the polymer, forming an alkyl radical. This alkyl radical can very quickly react with oxygen to form an alkyl peroxy radical, which propagates additional reactions. Each cyclohexane ring, whilst providing steric hindrance, also introduces two tertiary hydrogen atoms into the backbone of the polymer; that is two hydrogen atoms that are each bonded to a tertiary carbon. Due to the effects of electron withdrawal, the carbon hydrogen bond strength is reduced, such that the abstraction of these hydrogen atoms is much more likely at elevated temperatures. Hence, polyesters that contain this type of cyclohexane moiety are more prone to oxidative degradation than PET which has no tertiary hydrogen atoms in its polymer backbone.
[0009] The art of stabilizing polymers to oxidation at elevated temperatures is extensive. U.S. Pat. No. 5,763,512 teaches the use of a combination of a sterically hindered phenol and a specific organic phosphite for the stabilization of polyamides, polyesters or polyketones against oxidative, thermal and/or light induced degradation. Sterically hindered phenols and other organic compounds that can form resonance-stabilized radicals, are known to scavenge alkyl and alkyl peroxy radicals formed during the oxidation of a polymer, and are commonly termed primary anti-oxidants. Tri-aryl phosphites and thioester compounds react with hydroperoxide moieties formed during oxidation, and are commonly referred to as secondary anti-oxidants. Polymer Science and Engineering, Vol. 30, No. 17, page 1041 by A. Aurebach et al. cited herein, describes blends of PCT and the use of certain anti-oxidants to improve melt stability.
[0010] U.S. Pat. No. 5,981,062 attempts to improve the stability of such polyesters through blending with polyamides, more specifically the blending of polyesters based upon a polyhydric alcohol of 1,4-cyclohexane dimethanol with 5 to 20% of a polyamide, preferably PA66. The blends are shown to improve the oxidative and hydrolytic stability of monofilaments manufactured therefrom.
[0011] Polyamide 66 is known to form gels if held at elevated temperatures for an extended period of time (see Nylon handbook published by Hanser/Gardner Publications 1995, Chapter 3, Page 55). Polyesters derived from 1,4-cyclohexane dimethanol and terephthalic acid (or its esters); i.e. PCT, or polyesters derived from 1,4-cyclohexane dimethanol and terephthalic and isophthalic acid (or their esters); i.e. PCTA, have melting points of 295° C. and 285° C. respectively. These high melting points necessitate high temperature processing and melt temperatures which can be in excess of 300° C. We have seen that this will lead to some degree of gel formation with polyamide 66 and can result in some thermal degradation of PA6. Gels occur during melt processing when cross-links form between individual polymer chains. In monofilament extrusion, the presence of gels leads to diameter variation at localized sections of the filaments that are very brittle and exhibit poor mechanical properties. It is known that these filaments break under the normal loads experienced in a weaving process. Such filaments are of an unacceptable quality.
[0012] It is known to those skilled in the art that polyesters and polyamides are generally incompatible, and tend to exhibit phase separation in the melt. Phase separation induces micro-voids and various structural defects, the effect of which is to introduce weak points observed as tenacity variation along the length of the monofilament. These defects can also affect the drawing process, reducing the efficiency of monofilament manufacture.
[0013] In addition, the blends alone do not provide sufficient oxidative stability to match that of the industry standard polyester, PET, ensuring that they, and the monofilaments and textile structures derived from them, cannot be used universally. What is needed in the art is further stabilization of such polyesters, as described herein, against thermo-oxidative degradation. Textile structures formed from such monofilaments may be woven for a plurality of said filaments, or they may be constructed from helical spiral coils of the monofilaments linked together by pintle yarns, a process that is described in U.S. Pat. No. 4,423,543.
SUMMARY OF THE INVENTION
[0014] The present invention provides a PCTA copolymer for use in papermachine clothing and/or other industrial fabrics, having good dry heat and hydrolysis resistance.
[0015] According to a first aspect of the present invention there is provided a polyester composition comprising from 90 to 97% by weight of at least one polyester derived from the condensation of 1,4-cyclohexane dimethanol and at least one dicarboxylic acid or an ester thereof, from 0.1 to 5% of at least one primary anti-oxidant defined as an alkyl and/or alkyl peroxy radical scavenger, from 0.1 to 5% of at least one secondary anti-oxidant defined as a compound capable of decomposing a hydroperoxide, from 1 to 4% of at least one polyamide terpolymer.
[0016] The composition further preferably comprises from 0.5 to 2% of at least one hydrolysis stabilizer.
[0017] According to a second, aspect of the present invention there is provided an article of papermachine clothing comprising the polyester composition of the aforesaid first aspect of the invention.
[0018] According to a third aspect of the present invention there is provided a monofilament comprising the polyester composition of the first aspect of the invention.
[0019] The polymer compositions of the present invention exhibit comparable resistance to thermo-oxidative degradation to standard PET and vastly superior hydrolytic degradation, particularly at elevated temperatures, and improved property uniformity. Consequently the polymer compositions of the present invention may be processed using standard equipment with consistent properties.
[0020] The polyester compositions (which term as used herein includes copolyesters) of the present invention are those containing a cyclohexane moiety in the polymer backbone. The polyester preferably includes the condensation product of 1,4-cyclohexane dimethanol and terephthalic acid and/or an ester derivative of terephthalic acid. Ideally the polyester includes the condensation product of 1,4-cyclohexane dimethanol terephthalic and isophthalic acids and/or their ester derivatives. Suitable commercially available polyesters are those available from Eastman Chemical Co., of Kingsport Tenn. under the trade marks THERMX 3879 for PCT and THERMX 13319 for PCTA respectively.
[0021] The primary anti-oxidant may include from 0.1 to 5% by weight of the blend, and the secondary anti-oxidant may include from 0.1 to 5% by weight of the blend. The term “primary anti-oxidant” refers to a material that by way of its chemical composition can readily react with alkyl peroxy radicals forming more stable radicals that do not further propagate the chain reaction. These radicals can undergo further reaction with additional radicals to prevent them from propagating the oxidation chain. The most efficient primary anti-oxidants, by way of this reaction, are regenerated. The term “secondary anti-oxidant” refers to a class of additives that by way of their chemical composition can react with hydro-peroxide moieties formed as a result of the oxidation of a polymer, thus neutralizing these highly reactive species. Details of mechanisms involved in preventing oxidation are included in “Plastics Additives. Chapter 1 published by Hanser (1993)”. The primary anti-oxidant is preferably a hindered phenolic compound.
[0022] The type of primary anti-oxidant described in this art is exemplified by, but not limited to the following:
[0023] The phenolic anti-oxidant illustrated above, i.e. pentaerythrityl (tetrakis-3-(3,5-di-tert.-butyl-4-hydroxy phenyl) propionate), CAS Number 6683-19-8, is sold under the trade name IRGANOX 1010 by Ciba Corporation.
[0024] The secondary anti-oxidant is preferably a phosphite. The type of secondary anti-oxidant described in this art is exemplified by, but not limited to the following:
[0025] The phosphite secondary anti-oxidant illustrated above; i.e. Bis(2,4-dicumylphenyl)pentaerythritol diphosphite, CAS No. 154862-43-8, is sold under the trade name DOVERPHOS® S-9228 by Dover Chemicals, Dover, Ohio.
[0026] The hydrolysis stabilizer added to the blend was chosen for its ability to neutralize the carboxyl end groups of the polyester and is added in quantities to minimize the problems associated with manufacturing monofilaments from the blend. The composition may include the hydrolysis stabilizer in an amount from 0.5 to 2% by weight. The preferred stabilizer is exemplified by, but not limited to, the class of compounds known as carbodiimides. These compounds may be used in the monomeric or polymeric forms. A specific example of this type of stabilizer is 2,6 diisopropylphenyl carbodiimide which is supplied under the trade name of STABAXOL I by Rhein Chemie GmbH.
[0027] The polyamide terpolymer stabilizer ideally has a melting point in the range from 120° C. to 220° C. The terpolymer is added such that it includes from 1 to 4% by weight of the blend. An example of such a terpolymer is sold commercially by Du Pont de Nemours under the trade name ELVAMIDE 8063. The term “terpolymer” as used herein refers to a polymer composed from more than two distinct repeat units as opposed to a homopolymer with one, and a copolymer with two. For example, a polyamide terpolymer may be composed of three or more repeat units such as 6, 6,6, 11 and 12. The type and ratio of the components has a significant influence upon the properties of the material, such that they are useful. The term “polyamide” refers to any of the known polyamides, which through polymerization, can be formed into terpolymers. Examples include, but are not limited to polyamide 6, polyamide 11, polyamide 12, polyamide 6,6, polyamide 6,9, polyamide 6,10, polyamide 6,12.
[0028] The blend of a polyamide terpolymer, a primary anti-oxidant and a secondary anti-oxidant as defined herein combine synergistically to provide a significant improvement in the ability of the polyesters described to withstand oxidation at elevated temperatures. Furthermore the additives in the composition of the present invention have high compatibility to the main resin, unlike many prior art compositions, resulting in the compositions of the present invention having uniform properties including color, tensile properties and resistance to degradation.
[0029] The polyester composition blends of the present invention provide improved melt extrusion and consequently the consistency of monofilaments produced by such extrusion is improved.
[0030] An extrusion processing aid in the form of a lubricant, such as silicone, may be added to the blend, and can include between 0.1 and 1% by weight of the final composition.
[0031] The polyester compositions of the present invention are particularly useful as papermachine clothing or other industrial fabrics where the textile is likely to be exposed to elevated temperatures in the presence of water or otherwise high levels of humidity are anticipated. Such fabrics may be woven from a plurality of filaments or formed from many spiral coils linked together in a construction commonly termed a spiral fabric and described in U.S. Pat. No. 4,423,543.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
[0033] [0033]FIG. 1 is a graph of tensile strength retention as a function of time, illustrating the hydrolysis resistance of one example of the present invention compared with PET and PCTA. The hydrolysis test was performed as outlined in example 2; and
[0034] [0034]FIG. 2 is a graph of tensile strength retention as a function of time illustrating, the thermo-oxidative stability of one example of the invention compared with PET and PCTA. The oven-aging test was performed as outlined in Example 2.
[0035] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0036] The hydrolysis and oven aging resistance of a composition in accordance with the present invention were compared to that of a stabilized PET formulation, representing the industrial standard. Also, the hydrolysis and oven aging performance of the PCTA formulation reported in U.S. Pat. No. 5,981,062 was included for comparison.
EXAMPLE 1
[0037] In the following example, a comparison of the stabilizers that can be used is described, and their effect on the oxidative degradation of the monofilament outlined. The components in each sample were pre-blended, and then dried at 170° F. for 15 hours. Monofilament extrusion was carried out on a 1″ single screw extruder with an L/D ratio of 25:1. The resins were gravity fed into the extruder from a hopper, into which a positive pressure of nitrogen gas was maintained to prevent moisture ingress. The composition of the samples is provided in Table 1, and the extrusion conditions employed in this example are provided in Table 2.
[0038] The physical properties of this monofilament as produced were measured according to ASTM D2256-97.
[0039] The shrinkage was tested according to ASTM D204 with the temperature modified to 204° C. The physical properties of the samples are outlined in Table 3. Oven aging tests were carried out using a forced air oven maintained at 204° C. (400° F.). Lengths of the monofilaments samples were wrapped into coils approximately 5 cm in diameter. The coils were tied into bundles and placed in the oven, samples being removed at set time intervals. The physical property retention was measured as a function of tenacity on an Instron Tensile Tester. The tenacity retention data is provided in Table 3.
TABLE 1 Composition of various samples, including samples 1-6 manufactured following the procedure outlined in Example 1. Con- Sample trol 1 2 3 4 5 6 PET % PCTA 99.7 98.7 98.7 89.7 89.7 94.7 98.8 % Irganox 0.5 0.5 1010 (hindered phenolic) % Nylostab 0.5 S-EED (hindered amine) % Doverphos 0.5 0.5 0.5 S-9228 (phosphite) % tri-phenyl phosphate % Polyamide 6 10 % Polyamide 10 6, 6 % Polyamide 10 4 Terpolymer % MB50-004 0.3 0.3 0.3 0.3 0.3 0.3 0.3 UHMW Silicone Staboxol I 1.2
[0040] [0040] TABLE 2 Extrusion and Draw conditions employed in the manufacturing of the samples 1-6. Sample Control 1 2 3 4 5 6 Extruder Temperature Profile (C.) Throat <60 <60 <60 <60 <60 <60 <60 Feed Zone 280 280 280 280 280 280 280 Zone 2 285 285 285 285 285 285 285 Zone 3 290 290 290 290 290 290 290 Zone 4 290 290 290 290 290 290 290 Zone 5 285 285 285 285 285 285 285 Zone 6 275 275 275 275 275 275 275 Adaptor 285 285 285 285 285 285 285 Die 275 275 275 275 275 275 275 Extrusion Conditions Extruder Pressure 1000 1000 1000 1000 1000 1000 1000 (psi) Die Pressure (psi) 720 530 635 1030 750 600 680 Torque (M.g.) 2500 2500 2000 2500 2500 1900 2200 Screw Speed (rpm) 16 17 17 16 17 17 17 Drawing Conditions Total Draw Ration 3.33 3.33 3.33 3.33 3.33 3.33 3.33 Draw Oven Temperatures (F.) Oven 1 300 300 300 300 300 300 300 Oven 2 380 380 380 380 380 380 380 Oven 3 430 430 430 430 430 430 430
[0041] [0041] TABLE 3 Physical property results for the manufactured samples 1-6. Sample Control 1 2 3 4 5 6 PET Denier 3450 3492 3534 3326 3492 3462 3432 2486 Elongation @ Break 33 30 34 30 26 30 30 35 (%) Tenacity (g/d) Initial 2.24 2.22 2.2 2.18 2.21 1.83 1.83 3.8 24 hrs. Failed 2.22 1.72 1.36 1.43 1.57 39 hrs. 2.22 1.03 1.34 1.43 1.18 45 hrs. 2.22 1.03 0.96 1.36 1.3 65 hrs. 2.08 Failed Failed Failed 1.05 1.83 2.5 89 hrs. 1.56 1.05 1.72 2.51 113 hrs. Failed Failed 1.45 2.52
[0042] The control referred to in Tables 1 to 3 is PCTA as described in U.S. Pat. No. 5,981,062. Sample 6 is in accordance with the present invention.
[0043] Table 3 clearly shows that sample 5, manufactured using the polyamide terpolymer provides higher tenacity retention compared to either of the homopolymers PA6, or PA6,6 used in samples 3 and 4 respectively. In addition, comparison of samples 1, 5 and 6 illustrates the improvement found by combining the polyamide terpolymer and the anti-oxidants in a single blend.
[0044] Comparison of samples 1 and 2 shows the advantages of a hindered phenolic based anti-oxidant over a hindered amine, ensuring that this is the preferred primary anti-oxidant. By comparing samples 5 and 6 it is clear that the quantity of polyamide terpolymer used in the blend can be significantly reduced by utilizing a suitable combination of anti-oxidants. This provides advantages in processing, as the problems described herein associated with blending these two polymers are diminished significantly. This will be further illustrated in a later example.
[0045] A further embodiment of the present invention is the extension of the thermo-oxidative stability of the polyesters described herein such that they are comparable to the industry standard PET yarns. The data indicates that sample 6, which exemplifies the present invention retains 80% of its original tenacity after 113 hours at 204° C., whilst PET only retains 66% of its original tenacity following the same test period.
EXAMPLE 2
[0046] [0046] TABLE 4 Composition of samples 7-12, manufactured following the procedure outlined in Example 2 including extrusion and draw conditions. Sample 7 8 9 10 11 12 Composition % PCTA 98.8 95.8 91.8 91.8 91.85 91.85 Irganox 1010 0.5 0.5 0.5 0.6 0.6 Doverphos S-9228 0.5 0.5 0.5 0.6 Di-stearyl thiadi-propionate 0.6 Polyamide 6 4 Polyamide Terpolymar 4 3.35 3.75 Lubricant 0.4 Color 2 2 2 2 2 Staboxol I 1.2 1.2 1.2 1.2 1.2 1.2 Extruder Profile (F.) Zone 1 100 100 100 100 100 100 Zone 2 500 500 560 560 560 560 Zone 3 560 560 590 590 570 570 Zone 4 560 560 600 600 580 580 Zone 5 515 515 530 530 530 530 Zone 6 575 575 580 580 580 580 Zone 7 560 560 540 540 540 540 Zone 8 560 560 540 540 540 540 Zone 9 560 560 430 430 530 530 Zone 10 560 560 530 530 530 530 Zone 11 550 550 530 530 530 530 Adaptor 550 550 560 560 560 560 Head temperature setting 556 556 560 560 560 560 Extrusion Conditions Die temperature setting 518 518 560 560 560 560 Extruder Pressure (psi) 850 850 1000 1000 1000 1000 Extruder Speed (rpm) 125 125 140 140 125 125 Drawing Conditions Total Draw Ratio 3.43 3.43 3.43 3.43 3.43 3.43 Oven 1 300 300 300 300 300 300 Oven 2 320 320 300 300 310 310 Oven 3 330 330 290 290 280 280
[0047] [0047] TABLE 5 Physical property results for samples 7-12. Sample 7 8 9 10 11 12 PET Tenacity (g/den) 2.6 2.5 2.4 2.6 2.4 2.5 3.8 Elongation @ 20 20 20 21 19 20 35 Break (%) Shrinkage @ 13 12.5 14 13 2 140° C. (%) Hydrolysis Resistance Test Tenacity Retention 0 0 2.16 1.51 2.27 1.62 0 After 24 hrs @ 170° C. Steam (g/den) Oven-aging Test Tenacity Retention 0 1.7 1.94 1.92 2.16 2.15 2.5 After 89 hrs @ 204° C. (g/den) Tenacity Retention 0 0 0 1.19 1.94 1.73 1.63 After 137 hrs @ 204° C. (g/den)
[0048] Samples 10, 11 and 12 are in accordance with the present invention.
[0049] In a further example of the present invention, samples of the blends were manufactured using a 147 mm co-rotating and intermeshing twin screw extruder. The PCTA resin was dried at 260° F. for six hours, the blend components being metered into the polyester using a gravimetric, blending system. The composition was fed into the extruder such that the rate of feeding could be controlled. Table 4 provides the compositions and extrusion conditions for the samples. An organic pigment in the form of a masterbatch in a polymeric carrier resin was added to the samples to facilitate observation of filament defects. Table 5 outlines the physical properties, and summarizes the hydrolysis resistance and oven aging tests. FIGS. 1 and 2 illustrate the performance of the best of these blends relative to PET.
[0050] Hydrolysis resistance was measured by placing monofilament samples, wrapped into coils of approximately 5 cm diameter, in a pressure vessel or autoclave. The tests were performed at 170° C. (7.6 atm steam pressure), and 120° C. (1.96 atm steam pressure). The tenacity retention was measured according to ASTMD2256-97. Oven aging tests were carried out at 175° C. and 204° C.
[0051] Comparing samples 7 and 8 it can be clearly seen that the anti-oxidants improve the resistance to oxidation in the oven-aging test. Sample 10, incorporating the polyamide terpolymer, has significantly better oxidative stability than sample 9, that utilizes polyamide 6. The combination of stabilizers used in sample 11 provides the best performance, illustrating that by using a combination of stabilizers, it was possible to reduce the level of the polyamide terpolymer and improve the resistance to the industry standard PET.
[0052] [0052]FIG. 1 provides a comparison of the hydrolytic stability of sample 12 and PET, tested at 120° C. (1 atm). Clearly the new composition provides significantly improved property retention over the industry standard PET.
[0053] [0053]FIG. 2 illustrates the tenacity retention of sample 12 through the oven-aging test at 175° C., with comparison to the industry standard PET. It is evident that this composition has better property retention at elevated temperatures than the industry standard PET.
EXAMPLE 3
[0054] [0054] TABLE 6 Composition of samples 13 and 14, manufactured following the procedure outlined in Example 3 including experimental data. Sample 13 14 Composition % PCTA 90.1 91.85 Irganox 1010 0.2 0.6 Doverphos S-9928 0.2 0.6 Polyamide Homopolymer 4 Polyamide Terpolymer 3.75 Lubricant 1 Color 3 2 Staboxol I 1.5 1.2 Extrusion Pressure Range 200 50 Variation (+/−) Diameter Variation (%) 1.5 0.7 Filament Anomalies Present None
[0055] Sample 14 is in accordance with the invention.
[0056] In this example, two samples were once again manufactured using a 147 mm co-rotating and intermeshing twin screw extruder according to the method outlined in example 2. The compositions, processing data and physical appearance measurements are provided in Table 6. The extruder pressure variation was plotted against time for each of the samples and the data is presented as the maximum pressure range observed during the production of the samples. The diameter was measured using a laser scanner, commercially available from Lazermike. The data is expressed as the maximum % range of the diameters measured during the production of the filaments. The scan rate, and dwell time on each filament was kept constant.
[0057] By switching from polyamide homopolymer to a terpolymer, and optimizing amount of anti-oxidants added to the composition, the pressure variation was reduced by a factor of 4. One consequence of this pressure reduction is an improvement in the consistency of the filaments derived. This is clearly illustrated by the improvement in diameter variation when comparing samples 13 and 14.
[0058] The filament anomalies may be defined as short term diameter variation, what are termed “slubs” by those versed in the art, and other areas of non-uniform structure expressed as short term color variation. Modification of the composition by using less polyamide, and suitable anti-oxidants at optimized addition levels eliminates the anomalies found in filaments extruded from blends of polyamide homopolymer and PCTA.
[0059] It is to be understood that the above described examples are by way of illustration only. Many modifications and variations are possible.
[0060] While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A polyester composition comprising from 90 to 97% by weight of at least one polyester derived from the condensation of 1,4-cyclohexane dimethanol and at least one dicarboxylic acid or an ester thereof, from 0.1 to 5% by weight of at least one primary anti-oxidant defined as an alkyl and/or alkyl peroxy radical scavenger, from 0.1 to 5% by weight of at least one secondary anti-oxidant defined as a compound capable of decomposing a hydroperoxide, from 1 to 4% by weight of at least one polyamide terpolymer. Utility of such a composition includes use in a monofilament yarn or fiber, use in a papermachine clothing including such a monofilament yarn or fiber and/or including the polyester composition. | 3 |
FIELD OF THE INVENTION
The present invention is directed to power transmission devices, and in particular to an electromechanical actuator useful for adding or removing elements of a power transmitter, including auxiliary, automatic and manual transmissions, axles, and transaxles.
BACKGROUND OF THE INVENTION
Power transmissions are complicated machines, packing many mechanical devices into ever-smaller packages in order to meet cost and weight goals. A present-day transmission may use hydraulic bands to change gearing ratios and thus speeds. A simple two-speed transmission, such as one depicted in U.S. Pat. No. 5,588,928, is used to describe the involved gear and friction elements, and their functions during gear changes. FIG. 1 depicts a transmission consisting of a simple planetary gear unit 1 having an annulus gear 2 coupled with input shaft 3 , a sun gear 4 connected with brake drum 5 , and a planet carrier 6 connected with output shaft 7 . Planet gears 8 mesh with annulus gear 2 and sun gear 4 . A self-synchronizing friction band 10 is engaged to hold the drum 5 and the sun gear 4 attached thereto stationary to set the transmission in low gear. The transmission is upshifted to direct drive by applying multi-plate clutch 9 and by disengaging the friction band 10 to lock the planetary gear set for unitary rotation.
In FIG. 2 , the friction band 10 encircling the drum 5 has friction lining 11 attached to its inner surface. The band 10 also has lugs 12 , 13 secured to each end of the band; one lug 12 to the apply end and another lug 13 to the reaction end. Typically, the friction band actuating system 14 is housed inside a servo chamber 15 extending transversely in a transmission case 16 . The main components in the system are the apply piston 17 and the reaction piston 18 . Both pistons are subjected to the same pressure regulated by an exhaust control valve 19 , which is attached to the reaction piston guide rod 20 , responding to the axial movement of reaction piston 18 . Chamber 15 is enclosed by a servo cover 22 , which includes cylindrical surfaces and oil passages for both pistons as well as an elastomer ring 24 for sealing purposes. A complicated system to apply and release hydraulic pressure causes the band or bands to contract or relax, thus engaging or releasing a drive shaft encircled by the bands. Control system 25 for the selfsynchronized friction band includes a shift valve 26 and a mode valve 27 , including ball 28 and spring 29 . Ball 30 with seat 23 forms another valve. Hydraulic fluid or oil is supplied and directed through a series of pistons, accumulators, and chambers to control the bands.
Such complicated devices as this brake-band actuated transmission tend to have many components that must interact in a prescribed manner for correct operation. These parts and the resulting transmission are costly. The transmissions are subject to oil leaks. Wear may occur in many parts of the transmission, including the valve seats, the pistons, and the bands themselves. What is needed is a power transmitter having fewer parts and operating in a simpler fashion to add speed ranges to a mechanical transmission. Also, what is needed is a power transmitter that will shift and transmit power with fewer components and less cost, and in which the components are capable of acting simply and reliably to deliver mechanical power.
SUMMARY
One aspect of the invention is an electromechanical actuator for engaging a shaft. The electromechanical actuator comprises a housing that is fixedly mounted. Within the housing is a plurality of roller elements, such as roller bearings or needle bearings. There is a split ring around the shaft and within the housing, the ring urging the roller elements against an inside surface of the housing. The electromechanical actuator also comprises an engaging device, wherein the engaging device urges the split ring against the shaft. Another aspect of the invention is a method of manufacturing an electromechanical actuator. The method comprises molding a cage having a plurality of separating elements and a surface for engaging an engaging device. The method also comprises manufacturing an outer race and an inner race, at least one of the outer race and inner race having a cammed surface, and the method also comprises manufacturing a plurality of roller elements.
Another aspect of the invention is an auxiliary transmission, such as a transmission for an automobile or a truck. The auxiliary transmission comprises an input shaft, an output shaft, and a housing. The auxiliary transmission also comprises a planetary transmission connected with the shafts, and a sleeve connected with the planetary transmission. The auxiliary transmission also comprises an electromechanical actuator having a cammed surface, the actuator in rotatable contact with the sleeve and fixed to the housing. The auxiliary transmission has a first gear ratio when the sleeve rotates and a second gear ratio when the electromechanical actuator is engaged and prevents rotation of the sleeve.
Another aspect of the invention is an actuator, the actuator comprising an inner race for connecting with a first drive and an outer race for connecting with a second drive. The actuator further comprises a cage and a plurality of roller elements, the cage between the inner and outer races. At least one of an inner surface of the outer race and an outer surface of the inner race is a cammed surface. Another aspect of the invention is a two-speed transmission. The two-speed transmission comprises an input shaft and an output shaft, and a planetary transmission connecting the input shaft and the output shaft. The two-speed transmission also comprises an electromechanical actuator having a cammed surface and an engagement device for rotating a portion of the electromechanical actuator. The transmission has a first output ratio when the electromechanical actuator is in a first position and has a second output ratio when the electromechanical actuator is in a second position.
The electromechanical actuator of the present invention is bi-directional, that is, it may be operated with a mating shaft in either a clockwise or counter-clockwise direction of rotation. These and many other aspects and advantages of the invention will be seen in the figures and preferred embodiments of the invention described herein.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a diagrammatic representation of a prior art two-speed transmission.
FIG. 2 is a cross-sectional view of a prior art clutch mechanism.
FIG. 3 is a cross-sectional view of an electromechanical actuator according to the present invention.
FIG. 4 is a schematic diagram of an application of the electromechanical actuator of FIG. 3 .
FIG. 5 is a cross-sectional view of an auxiliary transmission using an embodiment of an electromechanical actuator.
FIG. 6 is a schematic view of a three-speed transmission using embodiments of an electromechanical actuator.
FIG. 7 is a plan view of a vehicle using a two speed transmission.
FIG. 8 is a cross-sectional view of an embodiment of a two-speed transmission having two electromechanical actuators.
FIG. 9 is an exploded perspective view of a portion of the electromechanical actuator.
FIGS. 10–11 are cross sectional views of the inner and outer races.
FIGS. 12–13 are cross-sectional views of embodiments of two-speed transmissions using two of the electromechanical actuators of FIG. 9 .
FIG. 14 is a cross-sectional view of a two-speed transmission using a single electromechanical actuator to shift gear ratios.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 is an embodiment of an electromechanical actuator 32 according to the present invention. The electromechanical actuator comprises an electric solenoid 33 mounted to housing 35 . Roller elements 31 are contained within the housing. The roller elements roll between the housing and an inner ring 38 , split along its length, so that the ring may be expanded or contracted by forces acting on the edges of the split. The electromechanical actuator acts on a shaft 39 that rotates within the split ring. When a user wishes to stop or prevent rotation of the shaft, the user actuates solenoid 33 . The solenoid then plunges plunger 34 into the split ring 38 between roller elements 31 . The plunger forces ring 38 to engage the rotating shaft 39 , stopping the shaft if it had been rotating, or preventing rotation if the shaft was already stopped. The inner surface of the housing may have a cammed profile of slightly raised surfaces 37 , gently radiused with a radius of curvature at least slightly greater than the radius of the roller elements. These raised surfaces, or arcuate surfaces, gently urge the roller elements radially inward in a circumferential motion, and thus contribute to engaging and stopping the shaft when it is rotating. Other radii of curvature may be used or added for the cammed profile on split ring 38 . This electromechanical actuator may be used in conjunction with any desired shaft.
One application is pictured in FIG. 4 , in which the electromechanical actuator 32 is used as a parking brake for axle half-shafts 36 . An auto has a transaxle 40 with half-shafts 36 to provide power to wheels 44 . The electromechanical actuator 32 may be mounted to a non-rotating axle housing 41 . During normal operation, the electromechanical actuator is not engaged, and the transaxle provides power to the wheels 44 . When the car is parked, and the operator desires to engage a parking brake, the operator actuates the solenoid of electromechanical actuator 32 . Plunger 34 causes interference of half-shaft 36 with the split ring 38 of the electromechanical actuator, and the auto is prevented from rolling.
The illustration is for an auto with a transaxle and two-wheel front drive, but the electromechanical actuator is usable also for rear wheels of a rearwheel drive car having a differential. The actuator housing should be mounted to a structure that does not rotate, in order to react the load upon a structure that does not move relative to the actuator housing. Instead of a solenoid-type actuator, other electro-mechanical devices may be used in embodiments of the present invention, such as a ballscrew, a ball-and-ramp device, and a cone friction clutch.
The electromechanical actuator may be used in transmission applications, such as auxiliary transmissions and multi-speed transmissions. FIG. 5 depicts a cross-section of an auxiliary transmission 45 using the electromechanical actuator 69 . Auxiliary transmission 45 includes a first housing portion 47 and a second housing portion 51 . The auxiliary transmission includes an input shaft 49 , such as from an engine or a primary transmission of a motor vehicle or truck. Output shaft 50 typically transmits power to a differential or other power transmitter of the vehicle or truck. Input shaft 49 is fixedly connected to ring gear 42 that meshes with planetary transmission 57 , and planet gears 59 . Planet gears 59 rotate on planet pins 61 . In one embodiment, there are four planet gears 59 rotating on four pins 61 . The pins are supported by carriers 58 and 63 . Planet pin 58 has an internal spline 60 and planet pin 63 has an internal spline or gear 66 . The shafts and carriers in turn are mounted on anti-friction bearings 67 supported by housing 47 or 51 or housing portion 62 .
Output shaft 50 mounts to housing portion 51 by bearing 67 on one end and has external splined gear 53 at the opposite end meshing with internal spline 60 from carrier 58 . Sleeve 52 mounts concentric to output shaft 50 and has external spline 55 for meshing with planetary gears 59 . The spline 55 acts as a sun gear in the planetary transmission 57 . Sleeve 52 also has a second splined gear 64 for meshing with internal spline 66 of carrier 63 . Electromechanical actuator 69 mounts concentric with and outside sleeve 52 . Electromechanical actuator 69 is preferably mounted fixedly to housing 51 to prevent rotation when engaged with sleeve 52 . The electromechanical actuator includes housing 71 , roller elements 73 and split ring 75 adjacent sleeve 52 . The electromechanical actuator also includes solenoid 77 . Control wires 79 pass through housing 51 via orifice 81 .
Operation of the auxiliary transmission and electromechanical actuator are as follows. Input power enters through the input shaft 49 and ring gear 42 . When ring gear 42 rotates, planet gears 59 also rotate. Since there is no restraint on carriers 58 and 63 , they rotate also, and thus spline 60 and sleeve 52 rotate. With spline 60 rotating, the output shaft 50 rotates also. The planetary gears are of no effect, since the entire inner assembly now rotates at the rotational speed of the input shaft, with the exception of the electromechanical actuator and its housing and controls.
When the electromechanical actuator is actuated, the split ring clamps onto sleeve 52 and prevents its rotation. Now when the input shaft 49 and ring gear 42 turn, the sleeve 52 , spline 64 and spline/sun gear 55 cannot rotate. The input shaft and its ring gear continue in gear contact with the planets 59 . The planets 59 , their pins 61 and their carriers 58 and 63 now rotate. Planet carrier 58 with internal spline 60 is in gear contact with the output shaft 50 through its external spline 53 at the inside end of the output shaft. In this position, the gear reduction takes place through the action of the ring gear and its pitch diameter relative to the planet gears and sun gear used. In one embodiment, a gear reduction of 1.4:1 is used. Other gear ratios may also be used as desired, such as a speed increase, or overdrive.
FIG. 6 depicts another embodiment of the invention, its application to a multi-speed transmission. Driveshaft 88 is attached to a ring gear 92 . Ring gear 92 is concentric with drive shaft 88 . Ring gear 92 meshes with a planetary gear set 94 having single gears and with a planetary gear set 95 having double gear elements. Double planetary gear set 95 has an inner ring contact gear 114 that is rigidly attached to outer gear 116 by shaft 110 . The diameter of the planetary gears in each gear set may be varied along with the number of teeth to alter the gear ratio as desired within the transmission. In this embodiment, planetary gear 116 is shown having a larger diameter and a greater number of teeth than the planetary gear 96 , which in turn has a larger diameter and more teeth than inner planetary gear 114 .
Both planetary gear sets 94 and 95 are supported by a common planet carrier 100 . Planet carrier 100 is rigidly attached to and concentrically located about driven shaft 90 . Planetary gear set 94 and planetary gear set 95 are rotatably attached by suitable shaft bearing assemblies 112 and 98 respectively. Rotary movement is transferred to driven output shaft 90 from ring gear 92 through either or both of planetary gear sets 94 and 95 . The transfer of rotation through the planetary gear sets 94 and 95 is determined by the rotational condition of inner and outer sun gears 102 and 118 , respectively, which act as speed control gears. In one preferred embodiment, sun gears 102 and 118 are the same diameter, but they may have different diameters depending on the desired gear ratios. Inner sun gear 102 meshes with the single planetary gear system 94 and is non-rotatably attached to one end of a hollow shaft 104 which is positioned about and concentrically over and is capable of rotation about, driven output shaft 90 . At its opposite end, a clutch disc 115 is attached to shaft 104 .
Outer sun gear 118 meshes with outer planetary gear 116 and is also attached to one end of a hollow shaft 108 . Shaft 108 is positioned concentrically over shaft 104 for rotation about shaft 104 . At an end opposite sun gear 118 , a rotor 117 is non-rotatably attached to shaft 108 . Rotor 117 also has a clutch caliper 119 for engaging clutch disk 115 . An electromechanical actuator, such as cone friction clutch 105 , according to the present invention is positioned over and concentric with shaft 104 and another electromechanical actuator, cone friction clutch 106 is positioned concentric with and over shaft 108 . The clutch and electromechanical actuators 105 and 106 are used to control the rotation of the sun gears 102 and 118 and effect speed changes within the transmission.
When the clutch is engaged, the transmission is in direct drive, with the speed of rotation of the output shaft equaling the speed of rotation of the input shaft. With the clutch engaged, all elements of the transmission that rotate move in unison, with all shafts and planetaries rotating. Therefore, the output rotational speed will equal the input rotational speed. To engage a first underdrive of the transmission, the clutch is released and electromagnetic actuator 106 is engaged. With actuator 106 engaged, shaft 108 cannot turn and sun gear 118 is fixed in position. Therefore, when ring gear 92 turns, planetary gear set 95 rotates about sun gear 118 . Rotation of planetary gear set 95 causes rotation of planet carrier 100 and also rotation of output shaft 90 . Shaft 104 and sun gear 102 are free to rotate, and they rotate idly along with planetary gear set 94 . The speed of the output shaft 90 is set by the ratios of the gear pitch diameters of ring gear 92 , inner planet gear 114 , outer planet gear 116 , and outer sun gear 118 .
A second underdrive speed is obtained by releasing electromagnetic actuator 106 and engaging only electromagnetic actuator 105 . With electromagnetic actuator 105 engaged, shaft 104 and inner sun gear 102 cannot rotate. As ring gear 92 rotates, single planetary gear set 94 rotates about sun gear 102 , which causes planet carrier 100 and output shaft 90 to rotate. Outer sun gear 118 revolves idly, as does double planetary gear set 95 . The speed of the output shaft 90 is set by the ratios of the diameters of ring gear 92 , planet gear 96 , and inner sun gear 102 . As is well known in the art, the same gears may be used in a reversing fashion to achieve an overdrive transmission by reversing the functions of the input and output shafts. In this case, a first overdrive may be obtained by actuating only electromagnetic actuator 106 and a second overdrive may be obtained by engaging only electromagnetic actuator 105 .
FIG. 7 is a plan view of an application using a two speed transmission 121 . A motor vehicle 120 , such as an automobile or truck, comprises an engine 122 and a transmission 124 mounted on a frame 126 . A first drive shaft 128 transmits power from the transmission to an auxiliary transmission 121 . The first drive shaft may function as an input shaft to the auxiliary transmission 121 . A second drive shaft 132 carries power from the auxiliary transmission 121 to a rear differential 138 and then to wheel shafts or halfaxles 139 to power the rear wheels of the vehicle. The drive shafts may be connected to the auxiliary transmission by U-joints 134 or other joints. The auxiliary transmission 121 may be a transmission according to the embodiment of FIG. 5 , or may be a simpler, 2-speed version of the embodiment of FIG. 6 . Control wires from the auxiliary transmission may be routed to an electronic control unit 136 , where a switch or other control is available to the operator of the vehicle.
A detailed view of a two-speed auxiliary transmission 130 is depicted in FIG. 8 . Two-speed auxiliary transmission 130 includes a flange gear 141 and input shaft 142 having a extension 143 . The transmission may also have a sun gear 145 and bushing 144 . The output from the transmission includes ring gear 147 and output shaft 148 with axle pinion gear 149 . A planetary transmission 150 within the two-speed transmission 130 includes sun gear 145 , planet gears 153 , planet pins 155 and carrier 157 . The sun gear also has an extension 151 for mounting to electromechanical actuators 165 and 170 . Extension 143 is fixedly linked to carrier 157 .
In this embodiment, actuator 165 acts as an idler, while actuator 170 acts to shift the two-speed transmission from one gear ratio to another when an operator of the vehicle desires. The outer race of actuator 170 is in fixed contact with the housing 160 , while its inner race is in rotatable contact with the gear extension 151 . The outer race of actuator 165 is in fixed contact with carrier 157 , while its inner race is in rotatable contact with sun gear extension 151 . In this embodiment, the two-speed transmission may be operated in straight-through mode or in under-drive mode. Other embodiments may have straight-through and an over-drive mode. In straight-through mode, actuator 170 does not engage, and sun gear 145 and sun gear extension 151 rotate. Input torque from input shaft 142 drives the sun gear 145 , causing the sun gear 145 and extension 151 to rotate at the input shaft speed. Extension 143 , tied to planet carriers 157 , also rotates, and therefore the planetary transmission 150 as a whole also rotates. Ring gear 147 rotates at the same speed as the input shaft, as does output shaft 148 and axle pinion gear 149 .
An underdrive mode may be used if the planetary transmission 150 has been designed and constructed by selection of ring gear 147 and planet gears 153 so that their input/output ratios will be some desired ratio, such as 1.4:1, that is, 1 output revolution per 1.4 input revolutions, for an underdrive mode. To utilize the underdrive mode, an operator or controller actuates electromechanical actuator 170 to engage. The cage of actuator 170 rotates through a portion of a revolution, locking the inner race to the outer race through roller bearing elements, and preventing rotation of sun gear extension 151 and therefore preventing rotation of sun gear 145 . When the input shaft 142 turns, sun gear extension 151 cannot rotate, nor can sun gear 145 . Extension 143 rotates at the speed of the input shaft 142 , as does carrier 157 . This causes the planet gears 153 of the planetary transmission to rotate about the sun gear. The ring gear rotates as driven by the planet gears, driving the output shaft 148 and axle pinion gear 149 at a desired underdrive ratio, such as 1.4:1. Thus, the operator of the vehicle can select a straight-through or an underdrive mode of operation.
Details of the electromechanical actuator 170 are shown in FIG. 9 . The actuator includes an inner race 171 , a plurality of roller elements 175 , a cage 176 , and an outer race 179 . The inner race 171 may be splined on its inner surface or otherwise designed to mate with a shaft or rotating member, such as sun gear extension 151 , or the surface may be smooth. Preferably, arcuate, cammed surfaces can exist on the inner circumference of outer race 179 , or the inner circumference of inner race 171 may have arcuate, cammed surfaces. The outer circumference of inner race 171 may comprise a plurality of arcuate surfaces 179 to match roller elements 175 , or the outer circumference may be smooth as shown. The inner race may also include a split 173 and a notch 174 for engaging a matching tab 177 on cage 176 . Cage 176 also includes a plurality of isolating members or fingers 178 for separating roller elements 175 . There may be two counter opposing return springs 169 (or two pair of return springs) held within cage 176 at 180° positions, for centering the inner and outer races and the cage in a neutrallycentered, free-wheeling position. A cross-sectional view of the inner race 171 is shown in FIG. 10 , and a cross-sectional view of the outer race is shown in FIG. 11 .
Cage 176 is preferably molded from a strong, relatively stiff plastic material having wear-resistant qualities, or the cage may be molded from powdered metal. The cage includes a plurality of fingers 178 to separate roller elements from each other. The outer circumference may have an engagement feature 172 on a portion of its surface, such as gear teeth for a gear sector. The engagement feature is meant to engage a mechanical device to rotate the cage a few degrees, thus engaging the electromechanical actuator. While cage 170 depicts helical gear sector 172 , other features that may be used to interface a mechanical device include a splined or cammed surface on the outer circumference of cage 176 .
As depicted in FIG. 10 , the inner race 171 has a smooth outer circumference 103 and a smooth inner circumference 113 , and also has a split 173 and a notch 174 . The split allows the inner race to expand slightly in a radial direction. However, the split also tends to interfere with desirable roundness of the inner race. This interference may take place both during operation and during manufacture of the inner race itself, since it is very difficult to hold roundness tolerances on a part that has been split. Therefore, the split feature should be placed on the inner ring in one of the later steps used to manufacture the race. The split may be placed by any convenient method of manufacture, such as machining, laser cutting, or water-jet cutting. The split should also be narrow, desirably from 0.001 to 0.020 inches in width, preferably from about 0.005 to about 0.010 inches. The split should also be as short as possible in length, to minimize distortion after the split has been made. One way to minimize work hardening is to leave the inner surface smooth, rather than adding cammed or arcuate surfaces, which also add distortion. The split need not be co-located circumferentially with the notch, but may be placed there, as shown in FIG. 9 , for convenience. The inner race 171 also preferably has a lubrication pattern imprinted or placed onto its inner circumference 113 , for interfacing with other parts. The lubrication pattern may be small, grooved pattern for retaining small amounts of oil on the surface, such as a series of axial grooves.
FIG. 11 depicts a cross-sectional view of outer race 179 . The outer circumference may have a spline 107 for interfacing to another element of the transmission, such as a housing. The inner circumference may have stops 182 to react leaf or compression springs 169 and maintain a preload on the cage and thus the actuator. The remainder of the inner circumference may include a plurality of relatively smooth surfaces 111 interrupted by raised surfaces 109 to separate the roller elements 175 . The raised surfaces also act as cammed surfaces. When the cage is rotated a few degrees, the fingers force the roller elements against raised surfaces 109 , thrusting the bearings radially inward and causing an engagement and lock-up between the inner and outer races. The corner radius of the raised surfaces with the inner circumference of the outer race is desirably at least somewhat larger than the radius of the roller bearing elements 175 , ensuring that the roller elements will be free to translate circumferentially and to rotate. Thus, the electromechanical actuator is engaged by rotating the cage and causing engagement between the inner and outer races.
The inner race 171 may be machined from barstock or preferably made from a powdered metal. If it is made from powdered metal, the notch and split may be molded in and distortion minimized during manufacture. The cage 176 is made from metal or preferably from an engineering plastic. The engineering plastics preferably include reinforced or unreinforced nylon, phenolic, or other high-performance engineering plastics. Cages may be made from thermoplastic or thermoset materials, and processes used to make them may include injection molding, compression molding, and other plastics processes. Manufacturing and machining processes for the inner and outer races, and the roller elements, are meant to include any sort process for shaping material, including but not limited to, casting, molding, forging, and machining processes. Other manufacturing processes using in making the components of the electromechanical actuator include turning, broaching, grinding, shaping, machining and honing. Net-shape or near-net shape processes, such as powder metal compaction and sintering processes, are also included in this definition of manufacturing processes.
Other embodiments may include a variety of devices for releasably engaging the sun gear extension with a housing of the two-speed transmission. These devices are used in automotive differentials, and include friction cone clutches, ball-and-ramp devices, and solenoids. FIG. 12 illustrates an auxiliary transmission using a ball and ramp device for engaging the electromechanical actuator. In FIG. 12 , the two-speed transmission works in the same manner as that described above for FIG. 8 . FIG. 13 depicts a solenoid for releasably engaging the transmission.
FIG. 12 is another embodiment of a two speed transmission 140 with an idling electromechanical actuator 180 and a second electromechanical actuator 180 in operable contact with a ball-and-ramp device 185 . The electromechanical actuators have inner races 192 a , 192 b , cages 194 a , 194 b , and outer races 196 a , 196 b , along with other internal parts, such as roller elements and springs, as previously described. The inner races 192 a , 192 b are in rotatable contact with the sun gear extension 151 , while outer race 196 b is in fixed contact with the housing 160 and outer race 196 a is in rotatable contact with carrier 157 . The ball and ramp device 185 may include a rotor 181 and a stator 183 . With respect to the second electromechanical actuator 180 , upon command, rotor 181 may rotate to cause cage 194 b to rotate engaging inner race 192 b and outer race 196 b . Since outer race 196 b is splined or otherwise grounded to housing 160 , inner race 192 b , cage 194 b , and outer race 196 b are unable to rotate. Thus, sun gear extension 151 and therefore sun gear 145 are also unable to rotate. With the sun gear stationary, the planetary gear system operates as described previously, including planets 153 and ring gear 147 .
FIG. 13 depicts another embodiment of a two-speed transmission 190 having two electromechanical actuators 195 , 197 . In this embodiment, first electromechanical actuator 195 is an electromechanical actuator as previously described, while second actuator 197 includes a solenoid 199 . The first and second actuator have inner races 192 a , 192 b , cages 194 a , 194 b , and outer races 196 a , 196 b , along with other parts as previously described. The solenoid 199 comprises a plunger 191 in a rotating track and coil 193 . Electric power to the solenoid is provided via slip rings (not shown). Upon actuation, the coil 193 may drive the plunger 191 and rotate it a short angle so that cage 194 b causes engagement of inner race 192 b with outer race 196 b of electromechanical actuator 197 through roller elements 175 . As previously described for FIGS. 8 and 12 , this causes the sun gear extension 151 and sun gear 145 to cease rotating, engaging the two speed transmission and placing the transmission into underdrive.
Another embodiment uses a single electromechanical actuator in a two speed auxiliary transmission. FIG. 14 depicts a two-speed transmission 200 with a single electromechanical actuator 210 and a planetary transmission 220 within housing 206 . In this embodiment, there is a flange gear 201 and a drive shaft 202 with drive shaft extension 203 , sun gear 204 and sun gear extension 205 . The electromechanical actuator 210 may include an inner race 216 in splined connection with sun gear 204 and sun gear extension 205 , and may also include cage 218 and outer race 219 . Not visible are the internal components, included roller elements, springs and the like, as previously described. This embodiment features a ballscrew 223 driving cage 218 and rotating the cage through an angle of a few degrees in response to controller 225 . Upon a signal from controller 225 , the ballscrew 223 may rotate the cage 218 , causing inner race 216 to lock up with outer race 219 , which is grounded to housing 206 . This prevents the sun gear 204 and sun gear extension 205 from rotating. Drive shaft 202 and extension 203 continue to rotate, as does planet carrier 208 . Planet gears 211 rotate about the sun gear 204 on planet pins 215 . The output of the planetary transmission 220 is taken through ring gear 207 , driven by the planet gears, and axle pinion gear 209 . The ratio between the input speed and the output speed of the transmission is set by the ratio of the planet gears 211 to the ring gear 207 in the planetary transmission. The electromechanical actuator 210 may use any other device that is convenient to rotate the cage and engage the electromechanical actuator, such as a ball-and-ramp mechanism or a solenoid, to engage the housing and thus the planetary transmission.
It is therefore intended that the foregoing description illustrates rather than limits this invention, and that it is the following claims, including all equivalents, which define this invention. Of course, it should be understood that a wide range of changes and modifications may be made to the embodiments and preferences described above. For instance, an overdrive speed range may be used as well as an under-drive range. Accordingly, it is the intention of the applicants to protect all variations and modifications within the valid scope of the present invention. It is intended that the invention be defined by the following claims, including all of the equivalents thereto. | An automotive transmission is equipped with a variety of gears that may be combined to yield one or more output speeds as compared to an input speed. One or more electromechanical actuators is used to engage or disengage a particular desired mix of gears. The electromechanical actuator engages one mix of gears or another to set the desired ratio of input speed to output speed. The transmission may be used to provide a straight-through, an underdrive speed range, or an overdrive speed range in an automotive transmission. | 5 |
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